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  Subjects -> PHYSICS (Total: 798 journals)
    - ELECTRICITY AND MAGNETISM (9 journals)
    - MECHANICS (19 journals)
    - NUCLEAR PHYSICS (49 journals)
    - OPTICS (85 journals)
    - PHYSICS (581 journals)
    - SOUND (23 journals)
    - THERMODYNAMICS (32 journals)

PHYSICS (581 journals)            First | 1 2 3 | Last

Showing 401 - 600 of 741 Journals sorted alphabetically
Nanoscale Research Letters     Open Access   (Followers: 3)
Nanospectroscopy     Open Access   (Followers: 1)
Nanotechnology Magazine, IEEE     Full-text available via subscription   (Followers: 32)
Natural Science     Open Access   (Followers: 10)
Nature Communications     Open Access   (Followers: 131)
Nature Materials     Full-text available via subscription   (Followers: 56)
Nature Physics     Full-text available via subscription   (Followers: 37)
NDT & E International     Hybrid Journal   (Followers: 47)
Neutron News     Hybrid Journal  
New Journal of Physics     Open Access   (Followers: 19)
Noise & Vibration Worldwide     Full-text available via subscription   (Followers: 3)
Noise Notes     Full-text available via subscription   (Followers: 2)
Nondestructive Testing And Evaluation     Hybrid Journal   (Followers: 15)
Nonlinear Dynamics     Hybrid Journal   (Followers: 5)
Novel Superconducting Materials     Open Access  
npj Computational Materials     Open Access  
npj Microgravity     Open Access  
npj Quantum Information     Open Access  
NTM Zeitschrift für Geschichte der Wissenschaften, Technik und Medizin     Hybrid Journal   (Followers: 3)
Nuclear Engineering and Design     Hybrid Journal   (Followers: 10)
Nuclear Medicine and Biology     Hybrid Journal   (Followers: 3)
Open Journal of Biophysics     Open Access   (Followers: 1)
Open Journal of Fluid Dynamics     Open Access   (Followers: 11)
Open Journal of Microphysics     Open Access  
Open Physics     Open Access   (Followers: 5)
Optical Communications and Networking, IEEE/OSA Journal of     Full-text available via subscription   (Followers: 13)
Optofluidics, Microfluidics and Nanofluidics     Open Access   (Followers: 1)
Organic Electronics     Hybrid Journal   (Followers: 4)
Organic Photonics and Photovoltaics     Open Access   (Followers: 1)
PAJ: A Journal of Performance and Art     Hybrid Journal   (Followers: 12)
Particuology     Hybrid Journal  
Pattern Recognition in Physics     Open Access   (Followers: 1)
Pergamon Materials Series     Full-text available via subscription  
Phase Transitions and Critical Phenomena     Full-text available via subscription  
Philosophical Magazine     Hybrid Journal   (Followers: 3)
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences     Full-text available via subscription   (Followers: 8)
Philosophy and Foundations of Physics     Full-text available via subscription   (Followers: 1)
Physica B: Condensed Matter     Hybrid Journal   (Followers: 6)
physica status solidi (a)     Hybrid Journal   (Followers: 1)
physica status solidi (b)     Hybrid Journal   (Followers: 2)
physica status solidi (c)     Hybrid Journal   (Followers: 1)
Physica Status Solidi - Rapid Research Letters     Hybrid Journal   (Followers: 1)
Physical Communication     Hybrid Journal   (Followers: 1)
Physical Review C     Full-text available via subscription   (Followers: 14)
Physical Review Special Topics - Physics Education Research     Open Access   (Followers: 4)
Physical Review X     Open Access   (Followers: 9)
Physical Sciences Data     Full-text available via subscription   (Followers: 1)
Physical Sciences Reviews     Full-text available via subscription  
Physics - spotlighting exceptional research     Full-text available via subscription   (Followers: 1)
Physics and Chemistry of Glasses - European Journal of Glass Science and Technology Part B     Full-text available via subscription   (Followers: 4)
Physics and Chemistry of Liquids: An International Journal     Hybrid Journal   (Followers: 1)
Physics and Chemistry of the Earth, Parts A/B/C     Hybrid Journal   (Followers: 6)
Physics and Materials Chemistry     Open Access   (Followers: 1)
Physics Essays     Full-text available via subscription   (Followers: 1)
Physics in Medicine & Biology     Full-text available via subscription   (Followers: 14)
Physics in Perspective     Hybrid Journal   (Followers: 2)
Physics International     Open Access   (Followers: 3)
Physics Letters A     Hybrid Journal   (Followers: 15)
Physics Letters B     Open Access   (Followers: 5)
Physics of Fluids     Hybrid Journal   (Followers: 32)
Physics of Life Reviews     Hybrid Journal   (Followers: 1)
Physics of Plasmas     Hybrid Journal   (Followers: 7)
Physics of the Dark Universe     Open Access   (Followers: 3)
Physics of the Solid State     Hybrid Journal   (Followers: 1)
Physics of Wave Phenomena     Hybrid Journal  
Physics Procedia     Open Access   (Followers: 1)
Physics Reports     Full-text available via subscription   (Followers: 3)
Physics Research International     Open Access   (Followers: 2)
Physics Today     Hybrid Journal   (Followers: 73)
Physics World     Full-text available via subscription   (Followers: 17)
Physics-Uspekhi     Full-text available via subscription  
Physik in unserer Zeit     Hybrid Journal   (Followers: 9)
Physik Journal     Hybrid Journal  
Plasma Physics and Controlled Fusion     Hybrid Journal   (Followers: 3)
Plasma Physics Reports     Hybrid Journal   (Followers: 2)
Pramana     Open Access   (Followers: 15)
Preview     Hybrid Journal  
Proceedings of the National Academy of Sciences     Full-text available via subscription   (Followers: 671)
Proceedings of the National Academy of Sciences, India Section A     Hybrid Journal   (Followers: 3)
Progress in Materials Science     Hybrid Journal   (Followers: 23)
Progress in Planning     Hybrid Journal   (Followers: 1)
Progress of Theoretical and Experimental Physics     Open Access  
Quantum Electronics     Full-text available via subscription   (Followers: 2)
Quantum Measurements and Quantum Metrology     Open Access  
Quantum Studies : Mathematics and Foundations     Hybrid Journal   (Followers: 3)
Quarterly Journal of Mechanics and Applied Mathematics     Hybrid Journal   (Followers: 3)
Radiation Effects and Defects in Solids     Hybrid Journal  
Radiation Measurements     Hybrid Journal   (Followers: 2)
Radiation Physics and Chemistry     Hybrid Journal   (Followers: 1)
Radiation Protection Dosimetry     Hybrid Journal   (Followers: 3)
Radiation Research     Full-text available via subscription   (Followers: 3)
Radiatsionnaya Gygiena = Radiation Hygiene     Open Access  
Radio Science     Full-text available via subscription   (Followers: 36)
Radiological Physics and Technology     Hybrid Journal  
Reflets de la physique     Full-text available via subscription  
Reports on Mathematical Physics     Full-text available via subscription   (Followers: 1)
Reports on Progress in Physics     Full-text available via subscription   (Followers: 3)
Research & Reviews : Journal of Physics     Full-text available via subscription   (Followers: 1)
Research in Drama Education     Hybrid Journal   (Followers: 10)
Research Journal of Physics     Open Access   (Followers: 14)
Results in Physics     Open Access   (Followers: 1)
Reviews in Mathematical Physics     Hybrid Journal  
Reviews in Physics     Open Access   (Followers: 1)
Reviews of Accelerator Science and Technology     Hybrid Journal   (Followers: 1)
Reviews of Geophysics     Full-text available via subscription   (Followers: 33)
Reviews of Modern Physics     Full-text available via subscription   (Followers: 29)
Revista Colombiana de Física     Open Access  
Revista de Física     Open Access  
Revista Mexicana de Astronomía y Astrofísica     Open Access  
Revista Mexicana de Física     Open Access  
Revista mexicana de física E     Open Access  
Rheologica Acta     Hybrid Journal   (Followers: 1)
Russian Journal of Mathematical Physics     Hybrid Journal  
Russian Journal of Nondestructive Testing     Hybrid Journal   (Followers: 4)
Russian Physics Journal     Hybrid Journal   (Followers: 1)
Samuel Beckett Today/Aujourd'hui     Full-text available via subscription   (Followers: 2)
Science and Technology of Nuclear Installations     Open Access   (Followers: 1)
Science China Physics, Mechanics & Astronomy     Hybrid Journal   (Followers: 2)
Scientific Reports     Open Access   (Followers: 37)
Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of     Hybrid Journal   (Followers: 46)
Sensor Letters     Full-text available via subscription   (Followers: 2)
Sensors and Actuators A: Physical     Hybrid Journal   (Followers: 118)
Services Computing, IEEE Transactions on     Hybrid Journal   (Followers: 5)
Shock and Vibration     Hybrid Journal   (Followers: 8)
Shock Waves     Hybrid Journal   (Followers: 5)
Small     Hybrid Journal   (Followers: 11)
Software Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 54)
Solid State Physics     Full-text available via subscription   (Followers: 1)
Solid-State Circuits Magazine, IEEE     Hybrid Journal   (Followers: 9)
Space Research Journal     Open Access   (Followers: 4)
Space Weather     Full-text available via subscription   (Followers: 16)
Spectral Analysis Review     Open Access  
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy     Hybrid Journal   (Followers: 17)
Spectrochimica Acta Part B: Atomic Spectroscopy     Hybrid Journal   (Followers: 17)
Spectroscopy and Spectral Analysis     Full-text available via subscription  
Spectroscopy Letters: An International Journal for Rapid Communication     Hybrid Journal   (Followers: 4)
Sri Lankan Journal of Physics     Open Access  
St. Petersburg Polytechnic University Journal : Physics and Mathematics     Open Access  
Strain     Hybrid Journal   (Followers: 2)
Strength of Materials     Hybrid Journal   (Followers: 6)
Structural Dynamics     Open Access   (Followers: 4)
Studies In Applied Mathematics     Hybrid Journal   (Followers: 1)
Superconductor Science and Technology     Hybrid Journal   (Followers: 2)
Surface Engineering     Hybrid Journal   (Followers: 3)
Surface Review and Letters     Hybrid Journal   (Followers: 1)
Surface Science Reports     Full-text available via subscription   (Followers: 15)
Surface Science Spectra     Hybrid Journal   (Followers: 1)
Surface Topography : Metrology and Properties     Full-text available via subscription  
Synchrotron Radiation News     Hybrid Journal   (Followers: 3)
Synthetic Metals     Hybrid Journal   (Followers: 4)
Technical Physics     Hybrid Journal  
Technical Physics Letters     Hybrid Journal  
Tectonics     Full-text available via subscription   (Followers: 13)
The European Physical Journal H     Hybrid Journal   (Followers: 2)
The European Physical Journal Plus     Open Access  
The International Journal of Multiphysics     Full-text available via subscription   (Followers: 1)
The Physics of Metals and Metallography     Hybrid Journal   (Followers: 16)
The Physics Teacher     Full-text available via subscription   (Followers: 99)
Theoretical and Computational Fluid Dynamics     Hybrid Journal   (Followers: 12)
Theoretical and Mathematical Physics     Hybrid Journal   (Followers: 6)
Topological Quantum Matter     Open Access  
Transport Phenomena in Nano and Micro Scales     Open Access  
Transport Theory and Statistical Physics     Hybrid Journal   (Followers: 4)
Tribology International     Hybrid Journal   (Followers: 41)
Tribology Letters     Hybrid Journal   (Followers: 5)
Tribotest     Hybrid Journal  
Turkish Journal of Physics     Open Access  
Ultrasonics     Hybrid Journal   (Followers: 5)
Ultrasonics Sonochemistry     Hybrid Journal   (Followers: 3)
Ultrasound in Medicine & Biology     Full-text available via subscription   (Followers: 8)
Universal Journal of Physics and Application     Open Access   (Followers: 2)
Unnes Physics Education Journal     Open Access   (Followers: 2)
Unnes Physics Journal     Open Access  
Waves, Wavelets and Fractals     Open Access  
Western Journal of Communication     Hybrid Journal   (Followers: 5)
Women & Performance: a journal of feminist theory     Hybrid Journal   (Followers: 5)
Women in Engineering Magazine, IEEE     Full-text available via subscription   (Followers: 11)
World Journal of Condensed Matter Physics     Open Access  
X-Acoustics: Imaging and Sensing : Photoacoustics, Thermoacoustics, Magnetoacoustics     Open Access  
Zeitschrift für angewandte Mathematik und Physik     Hybrid Journal   (Followers: 1)
Zeitschrift für Naturforschung A : A Journal of Physical Sciences     Open Access  

  First | 1 2 3 | Last

Journal Cover Bauphysik
  [SJR: 0.194]   [H-I: 5]   [2 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0171-5445 - ISSN (Online) 1437-0980
   Published by John Wiley and Sons Homepage  [1605 journals]
  • Titelbild: Bauphysik 6/2016
    • Abstract: Mit einem klaren, schlichten Kubus, kontrastreich und zugleich in sich stimmig, hat die FLOSUNDK architektur+urbanistik GmbH das Thema Stadthaus neu interpretiert. Für die Natürlichkeit, Energieeffizienz sowie den Nutzungskomfort des neuen Büro- und Wohnhauses in Saarbrücken sorgt die monolithische Bauweise aus Liapor-Leichtbeton. Dessen unterschiedliche Sichtbetonausführungen sind dabei maßgeblich für die Lebendigkeit des Gebäudekubus verantwortlich. Aber nicht nur das Stadthaus, auch dessen – teils unter Denkmalschutz stehendes – Gebäudeumfeld wird durch seine Form und Funktion neu definiert. (Foto: Liapor)
      PubDate: 2016-12-01T05:22:21.911652-05:
      DOI: 10.1002/bapi.201690047
       
  • Vorschau 1/2017
    • Abstract: Jan Schiefelbein, Amir Javadi, Michael Diekerhof, Dirk Müller: Modellierung und Optimierung von MischgebietenStefan Krispel, Martin Peyerl, Philipp Weihs, Gerald Maier: Urban Heat Islands – Reduktion von innerstädtischen Wärmeinseln durch WhitetoppingJohannes Stegner, Christoph Drefke, Henok Hailemariam, Hauke Anbergen, Frank Wuttke, Ingo Sass: Ermittlung der Wärmeleitfähigkeit von Bettungsmaterial im ErdkabeltrassenbauChristoph Kempkes, Anton Maas, Martin Schäfers, Stephan Schlitzberger: Einfluss der Wärmespeicherfähigkeit auf Heizwärmebedarf und thermischen KomfortStefan Maas, Jessica Brensing, Max Flies, Georges Steffgen: Untersuchung des thermischen Komforts und der Luftqualität an vier neuen energieeffizienten Luxemburger Schulen mit und ohne LüftungsanlagenSebastian Hauswaldt, Sven Kaudelka: Untersuchungen zum Brandverhalten EPS-basierter Wärmedämmverbundsysteme (WDVS) bei Brandbeanspruchungen im SockelbereichVolker Brombacher, Franco Michel, Wolfram Scheiding, Marco Tores Uribe, Peter Niemz: Untersuchungen zum Einfluss einer nachträglichen Wärmebehandlung auf das Dämmverhalten von Holzfaserplatten
      PubDate: 2016-12-01T05:22:21.529545-05:
      DOI: 10.1002/bapi.201690056
       
  • Inhalt: Bauphysik 6/2016
    • PubDate: 2016-12-01T05:22:20.856896-05:
      DOI: 10.1002/bapi.201690055
       
  • Evaluation of genipin for stabilization of decellularized porcine
           cartilage
    • Authors: Steven Elder; Amanda Pinheiro, Christian Young, Preston Smith, Emily Wright
      Abstract: We speculate that an acellular osteochondral xenograft may be a good alternative to allografts for repair of focal articular cartilage lesions. In order to make a xenograft resistant to enzymatic degradation and to prevent a chronic immune response it may beneficial to stabilize it through crosslinking. The concept is analogous to treatment of porcine bioprosthetic heart valves with glutaraldehyde. The purpose of this study was to evaluate genipin, a natural crosslinking agent with low cytotoxicity, for stabilization of decellularized cartilage. Porcine articular cartilage discs were decellularized in SDS and nucleases and then crosslinked in genipin. The utility of genipin was determined from its effects on degree of crosslinking, mechanical properties, dimensional stability, enzymatic resistance, and in vitro biocompatibility. Degree of crosslinking, compressive moduli, and collagenase resistance varied over a wide range depending on genipin concentration. The equilibrium compressive modulus could be increased from approximately 50% to more than 120% that of native cartilage, and the time to complete degradation by collagenase could be extended from less than 12 hours to more than 15 days. Radial shrinkage of approximately 4% was observed at a genipin concentration of 0.1% wt/vol, and cartilage coefficient of friction against glass increased in a concentration-dependent manner. Autologous chondrocytes displayed little difference in viability or their ability to attach and spread over the surface of genipin-fixed cartilage compared to non-crosslinked cartilage during 6 weeks of culture. These results indicate that genipin may be efficacious for stabilization of a decellularized porcine osteochondral xenograft. This article is protected by copyright. All rights reserved
      PubDate: 2016-11-18T06:26:08.277877-05:
      DOI: 10.1002/jor.23483
       
  • Radiolucency in stemless shoulder arthroplasty is associated with an
           imaging phenomenons
    • Authors: Robert Hudek; Birgit Werner, Ayman F. Abdelkawi, Rainer Schmitt, Frank Gohlke
      Abstract: Stemless humeral implants show comparable midterm clinical results compared to stemmed components. Recently, radiolucencies around the metaphyseal seating of humeral stemless implants were reported on postoperative radiographs. It is controversial whether they are attributable to bone resorption. We hypothesized these radiolucencies result from imaging artifacts. Seven cadaveric specimens (3 male and 4 female) were first radiographed and then scanned with CT. A stemless humeral component of current design was implanted in each specimen. After implantation, all specimens were radiographed with different exposure settings. The implant was removed, and the specimens were scanned with CT again. Pre- and post-implantation radiographs and CT scans were compared. The mean Hounsfield units (HU) at the humeral resection plane from the pre-implantation CT were correlated with the diameter of the radiolucent halo on the post-implantation radiographs. A symmetric radiolucent halo of variable diameters occurred on all radiographs after implantation when an automatic exposure control was used. The halo disappeared in all specimens when the tube voltage was reduced. Lower CT-values (HU) before the implantation resulted in greater halos on the radiograph after implantation. Symmetric radiolucent halos can result from imaging artifacts, which is most likely due to radiation scatter. The halos can be minimized by reducing the tube voltage. The halo effect appears to be pronounced in bones with decreased density. This article is protected by copyright. All rights reserved
      PubDate: 2016-11-10T04:50:26.655115-05:
      DOI: 10.1002/jor.23478
       
  • Chemokines and inflammation in osteoarthritis: Insights from patients and
           animal models
    • Authors: Carla R. Scanzello
      Abstract: Evidence has been building that the pathologic drive for development of osteoarthritis (OA) involves more than simple mechanical “wear and tear.” Inflammatory mechanisms play an important role in the tissue response to joint injury, and are involved in development of post-traumatic OA. Inflammation also appears integral to the progression of OA, whether post-traumatic or spontaneous, contributing to the evolution of joint tissue degradation and remodeling as well as joint pain. Both patient-based studies and in vivo models of disease have shed light on a number of inflammatory pathways and mediators that impact various aspects of this disease, both structurally and symptomatically. Recent work in this field has implicated inflammatory chemokines in osteoarthritis pathogenesis. Expression of multiple chemokines and their receptors is modulated during disease in both patients and animal models. Although best known for their effects on leukocyte migration and trafficking within the immune system, chemokines can have a wide variety of effects on both motile and non-motile cell types, impacting proliferation, differentiation and activation of cellular responses. Their role in OA models has also demonstrated diverse effects on disease that exemplify their wide-ranging effects. Understanding how these important mediators of inflammation impact joint disease, and whether they can be targeted therapeutically, is actively being investigated by many groups in this field. This narrative review focuses on evidence published within the last five years highlighting chemokine-mediated pathways with mechanistic involvement in osteoarthritis and joint tissue repair. This article is protected by copyright. All rights reserved
      PubDate: 2016-11-03T05:59:26.13383-05:0
      DOI: 10.1002/jor.23471
       
  • Assessment of magnetic field interactions and
           radiofrequency-radiation-induced heating of metallic spinal implants in 7
           T field
    • Authors: Itsuko Tsukimura; Hideki Murakami, Makoto Sasaki, Hirooki Endo, Daisuke Yamabe, Ryosuke Oikawa, Minoru Doita
      Abstract: The safety of metallic spinal implants in magnetic resonance imaging (MRI) performed using ultrahigh fields has not been established. Hence, we examined whether the displacement forces caused by a static magnetic field and the heating induced by radiofrequency radiation are substantial for spinal implants in a 7 T field. We investigated spinal rods of various lengths and materials, a screw, and a cross-linking bridge in accordance with the American Society for Testing and Materials guidelines. The displacement forces of the metallic implants in static 7 T and 3 T static magnetic fields were measured and compared. The temperature changes of the implants during 15-min-long fast spin-echo and balanced gradient-echo image acquisition sequences were measured in the 7 T field. The deflection angles of the metallic spinal materials in the 7 T field were 5.0°–21.0° [median: 6.7°], significantly larger than those in the 3 T field (1.0°–6.3° [2.2°]). Among the metallic rods, the cobalt–chrome rods had significantly larger deflection angles (17.8°–21.0° [19.8°]) than the pure titanium and titanium alloy rods (5.0°–7.7° [6.2°]). The temperature changes of the implants, including the cross-linked rods, were 0.7°C–1.0°C [0.8°C] and 0.6°C–1.0°C [0.7°C] during the fast spin-echo and balanced gradient-echo sequences, respectively; these changes were slightly larger than those of the controls (0.4°C–1.1°C [0.5°C] and 0.3°C–0.9°C [0.6°C], respectively). All of the metallic spinal implants exhibited small displacement forces and minimal heating, indicating that MRI examinations using 7 T fields may be performed safely on patients with these implants. This article is protected by copyright. All rights reserved
      PubDate: 2016-10-21T16:45:21.990203-05:
      DOI: 10.1002/jor.23464
       
  • Peri-prosthetic tissue cells show osteogenic capacity to differentiate
           into the osteoblastic lineage
    • Authors: Monique AE Schoeman; Angela E Oostlander, Karien E de Rooij, Edward R Valstar, Rob GHH Nelissen
      Abstract: During the process of aseptic loosening of prostheses, particulate wear debris induces a continuous inflammatory-like response resulting in the formation of a layer of fibrous peri-prosthetic tissue at the bone-prosthesis interface. The current treatment for loosening is revision surgery which is associated with a high morbidity rate, especially in old patients. Therefore, less invasive alternatives are necessary. One approach could be to re-establish osseointegration of the prosthesis by inducing osteoblast differentiation in the peri-prosthetic tissue. Therefore, the aim of this study was to investigate the capacity of peri-prosthetic tissue cells to differentiate into the osteoblast lineage. Cells isolated from peri-prosthetic tissue samples (n = 22) – obtained during revision surgeries – were cultured under normal and several osteogenic culture conditions. Osteogenic differentiation was assessed by measurement of Alkaline Phosphatse (ALP), mineralization of the matrix and expression of several osteogenic genes. Cells cultured in osteogenic medium showed a significant increase in ALP staining (p = 0.024), mineralization of the matrix (p 
      PubDate: 2016-10-07T06:49:24.862842-05:
      DOI: 10.1002/jor.23457
       
  • The effect of platelet-rich plasma on degeneration change of rotator cuff
           muscles: In vitro and in vivo evaluations
    • Authors: Fumiaki Takase; Atsuyuki Inui, Yutaka Mifune, Ryosuke Sakata, Tomoyuki Muto, Yoshifumi Harada, Yasuhiro Ueda, Takeshi Kokubu, Masahiro Kurosaka
      Abstract: Atrophy with fatty degeneration is often seen in rotator cuff muscles with torn tendons. PRP has been reported to enhance tissue repair processes after tendon ruptures. However, the effect of PRP on atrophy and fatty degeneration of the muscle is not yet known. The aim of this study is to examine the effect of PRP on degeneration change of rotator cuff muscles in vitro and in vivo. A murine myogenic cell line and a rat rotator cuff tear model were used in this study and PRP was administrated into subacromial space which is widely used in clinical practice. In in vitro study, administration of PRP to C2C12 cells stimulated cell proliferation while inhibited both myogniec and adipogenic differentiation. In in vivo study, administration of PRP suppressed Oil Red-O positive lipid droplet formation. The expression of adipogenic genes was also decreased by PRP administration. In conclusion, PRP promoted proliferation of myoblast cells, while inhibiting adipogenic differentiation of myoblast cells and suppressing fatty degeneration change in rat torn rotator cuff muscles. Further investigations are needed to determine the clinical applicability of the PRP. This article is protected by copyright. All rights reserved
      PubDate: 2016-09-29T14:05:03.845556-05:
      DOI: 10.1002/jor.23451
       
  • Location of the tibial tunnel aperture affects extrusion of the lateral
           meniscus following reconstruction of the anterior cruciate ligament
    • Authors: Yuya Kodama; Takayuki Furumatsu, Shinichi Miyazawa, Masataka Fujii, Takaaki Tanaka, Hiroto Inoue, Toshifumi Ozaki
      Abstract: The anterior root of the lateral meniscus provides functional stability to the meniscus. In this study, we evaluated the relationship between the position of the tibial tunnel and extrusion of the lateral meniscus after anterior cruciate ligament reconstruction, where extrusion provides a proxy measure of injury to the anterior root. The relationship between extrusion and tibial tunnel location was retrospectively evaluated from computed tomography and magnetic resonance images of 26 reconstructed knees, contributed by 25 patients aged 17 to 31 years. A measurement grid was used to localize the position of the tibial tunnel based on anatomical landmarks identified from the three-dimensional reconstruction of axial computed tomography images of the tibial plateaus. The reference point-to-tibial tunnel distance (mm) was defined as the distance from the midpoint of the lateral edge of the grid to the posterolateral aspect of the tunnel aperture. The optimal cutoff of this distance to minimize post-operative extrusion was identified using receiver operating curve analysis. Extrusion of the lateral meniscus was positively correlated to the reference point-to-tibial tunnel distance (r2 = 0.64; P 5 mm was 0.40 ± 0.43 mm, compared to 1.40 ± 0.51 mm for a distance ≤5 mm (P 
      PubDate: 2016-09-27T14:34:25.564669-05:
      DOI: 10.1002/jor.23450
       
  • Development of arthrogenic joint contracture as a result of pathological
           changes in remobilized rat knees
    • Authors: Akinori Kaneguchi; Junya Ozawa, Seiichi Kawamata, Kaoru Yamaoka
      Abstract: This study aimed to elucidate how rats recover from immobilization-induced knee joint contracture. Rats' right knees were immobilized by an external fixator at a flexion of 140° for three weeks. After removal of the fixator, the joints were allowed to move freely (remobilization) for 0, 1, 3, 7, or 14 days (n = 5 each). To distinguish myogenic and arthrogenic contractures, the passive extension range of motion was measured before and after myotomy of the knee flexors. Knee joints were histologically analyzed and the expression of genes encoding inflammatory or fibrosis-related mediators, interleukin-1β (1L-1β), fibrosis-related transforming growth factor-β1 (TGF-β1), and collagen type I (COL1A1) and III (COL3A1), were examined in the knee joint posterior capsules using real-time PCR. Both myogenic and arthrogenic contractures were established within three weeks of immobilization. During remobilization, the myogenic contracture decreased over time. In contrast, the arthrogenic contracture developed further during the remobilization period. On day 1 of remobilization, inflammatory changes characterized by edema, inflammatory cell infiltration, and upregulation of IL-1β gene started in the knee joint posterior capsule. In addition, collagen deposition accompanied by fibroblast proliferation, with upregulation of TGF-β1, COL1A1, and COL3A1 genes, appeared in the joint capsule between days 7 and 14. These results suggest the progression of arthrogenic contracture following remobilization, which is characterized by fibrosis development, is possibly triggered by inflammation in the joint capsule. It is therefore necessary to focus on developing new treatment strategies for immobilization-induced joint contracture. This article is protected by copyright. All rights reserved
      PubDate: 2016-09-07T05:35:40.17151-05:0
      DOI: 10.1002/jor.23419
       
  • Hip biomechanics during stair ascent and descent in people with and
           without hip osteoarthritis
    • Authors: Michelle Hall; Tim V Wrigley, Crystal O Kean, Ben R Metcalf, Kim L Bennell
      Abstract: Hip osteoarthritis (OA) is often associated with pain and impaired function. Understanding biomechanical alterations in patients with hip OA during challenging activities such as stair use is important to inform treatments. The aim of this study was to determine whether kinematics and kinetics during stair ambulation differed between people with hip OA and healthy controls. Fifteen participants with symptomatic and radiographic hip OA and 15 asymptomatic healthy controls underwent 3-D motion analysis during stair ascent and descent. Trunk, pelvis and hip kinematics as well as hip kinetics were evaluated. Analyses were performed unadjusted and adjusted for speed and leg length. In both the unadjusted and adjusted analyses, participants with hip OA ascended stairs with less hip range of motion in all three planes and a lower peak external rotation moment compared to controls. In the unadjusted analysis, hip OA participants descended stairs with greater ipsilateral trunk lean, less sagittal plane range of motion, lower peak extension moment, lower peak external rotation moment, and greater hip adduction moment impulse compared to controls. In the adjusted results, peak internal rotation moment and hip adduction moment impulse were greater in hip OA participants compared to controls. Findings show that individuals with hip OA display limited range of hip joint movement, particularly during stair ascent, and overall indicate the use of strategies (e.g. trunk lean; lower peak external rotation moment; higher adduction moment impulse) that implicate altered hip abductor function. Future research is required to further understand the implications of these findings on hip OA. This article is protected by copyright. All rights reserved
      PubDate: 2016-08-30T05:45:27.631595-05:
      DOI: 10.1002/jor.23407
       
  • Pain-related behavior and the characteristics of dorsal-root ganglia in a
           rat model of hip osteoarthritis induced by mono-iodoacetate
    • Authors: Shuichi Miyamoto; Junichi Nakamura, Seiji Ohtori, Sumihisa Orita, Takayuki Nakajima, Takanori Omae, Shigeo Hagiwara, Makoto Takazawa, Miyako Suzuki, Takane Suzuki, Kazuhisa Takahashi
      Abstract: This principal aim of this study was to clarify the time course of pain-related behavior and pain-related sensory innervation in a rat model of hip osteoarthritis (OA) induced by intra-articular injection of mono-iodoacetate (MIA). Using sixty six-week-old male Sprague Dawley rats, 25 μl of sterile saline of 1% Fluoro-Gold solution (FG) (control group; n = 30) and 25 μl of sterile saline of 1% FG with 2 mg of MIA (MIA group; n = 30) was injected into the right hip joints. Gait function was evaluated using a CatWalk system after 7, 14, 28, 42, and 56 days (n = 5, respectively). Neurons in the dorsal root ganglion (DRG) between L1 and L5 were immunostained for calcitonin gene-related peptide (CGRP) and activating transcription factor-3 (ATF3). Gait analysis revealed the mean six parameters of hind paws at all time points were significantly lower in the MIA group (P = 0.05). The number of CGRP-immunoreactive (-IR) DRG neurons was significantly increased on days 7, 14, 28, and 42 peaking at 14 days in the MIA group. By contrast, expression of ATF3-IR in FG-labeled DRG neurons was significantly increased on days 42 and 57. The FG-labeled DRG neurons were distributed between L1 and L5, mainly at the L4 level. Pain-related behavior indicated by gait disturbance was observed in a MIA model of hip OA in rat. Early elevation of CGRP expression and late expression of ATF-3 were demonstrated in DRG neurons, possibly reflecting inflammatory pain and neuropathic pain in hip OA. This article is protected by copyright. All rights reserved
      PubDate: 2016-08-20T15:25:24.548957-05:
      DOI: 10.1002/jor.23395
       
  • Comparison of tibiofemoral joint space width measurements from standing CT
           and fixed flexion radiography
    • Authors: Neil A. Segal; Eric Frick, Jeffrey Duryea, Michael C. Nevitt, Jingbo Niu, James C. Torner, David T. Felson, Donald D. Anderson
      Abstract: The objective of this project was to determine the relationship between medial tibiofemoral joint space width measured on fixed-flexion radiographs and the three-dimensional joint space width distribution on low-dose, standing CT (SCT) imaging. At the 84-month visit of the Multicenter Osteoarthritis Study, 20 participants were recruited. A commercial SCT scanner for the foot and ankle was modified to image knees while standing. Medial tibiofemoral joint space width was assessed on radiographs at fixed locations from 15–30% of compartment width using validated software and on SCT by mapping the distances between three-dimensional subchondral bone surfaces. Individual joint space width values from radiographs were compared with three-dimensional joint space width values from corresponding sagittal plane locations using paired t-tests and correlation coefficients. For the 4 medial-most tibiofemoral locations, radiographic joint space width values exceeded the minimal joint space width on SCT by a mean of 2.0mm and were approximately equal to the 61st percentile value of the joint space width distribution at each respective sagittal-plane location. Correlation coefficients at these locations were 0.91–0.97 and the offsets between joint space width values from radiographs and SCT measurements were consistent. There were greater offsets and variability in the offsets between modalities closer to the tibial spine. Joint space width measurements on fixed-flexion radiographs are highly correlated with three-dimensional joint space width from SCT. In addition to avoiding bony overlap obscuring the joint, a limitation of radiographs, the current study supports a role for SCT in the evaluation of tibiofemoral OA. This article is protected by copyright. All rights reserved
      PubDate: 2016-08-09T18:01:28.552588-05:
      DOI: 10.1002/jor.23387
       
  • Normal multiplanar movement of the spinal cord during unilateral and
           bilateral straight leg raise: Quantification, mechanisms and overview
    • Authors: Marinko Rade; Michael Shacklock, Mervi Könönen, Jarkko Marttila, Ritva Vanninen, Markku Kankaanpää, Olavi Airaksinen
      Abstract: The purpose of this investigation was to provide a full set of normal data describing neural biomechanics within the vertebral canal in all three planes with unilateral and bilateral SLR tests to allow for clinical comparison with clinical cases. This is done following the notion that, due to neural continuum, tensile forces are transmitted through the lumbosacral nerve roots and dura to the conus medullaris (linear dependency principle).In this controlled radiologic study 10 asymptomatic volunteers were scanned with 1.5T magnetic resonance scanner (Siemens Magnetom Aera, Erlangen, Germany) using different scanning sequences for planning and for measurement purposes. Conus displacement in both antero-posterior direction (sagittal slices) and lateral direction (axial slices) was quantified during unilateral passive left, right SLR and bilateral SLR and compared with the position of the conus in the neutral (anatomic) position.It is shown that the conus medullaris displaced laterally and anteroposteriorly in response to unilateral and bilateral SLRs. Pearson's correlations were higher than 0.95 for both intra- and inter-observer reliability. The observed power was higher than 0.99 for all the variables tested.Following this, the authors conclude that lateral and antero-posterior displacement of conus medullaris into the vertebral canal occurs consistently with unilateral and bilateral SLRs following directions predicted by tension vectors. Summative information collected in this line of research in neuroradiology is here presented. We believe we have presented the first conclusive and complete full set of normal data on non-invasive, in vivo, normative measurement of spinal cord displacement with the SLR ever presented. This article is protected by copyright. All rights reserved
      PubDate: 2016-08-09T17:35:39.595826-05:
      DOI: 10.1002/jor.23385
       
  • Adipokines induce pro-inflammatory factors in activated CD4+ T cells from
           osteoarthritis patients
    • Authors: Morena Scotece; Tamara Pérez, Javier Conde, Vanessa Abella, Veronica López, Jesús Pino, Miguel A. Gonzalez-Gay, JJ Gomez-Reino, Antonio Mera, Rodolfo Gomez, Oreste Gualillo
      Abstract: Osteoarthritis (OA) is a chronic systemic musculoskeletal disorder involving inflammation, immunity and metabolic alterations. OA is commonly regarded as non-inflammatory disease; still inflammation is recognized as contributing to the symptoms and progression of OA. New evidence suggests that adipokines are involved in the pathophysiology of OA and might modulate the production of inflammatory mediators including in immune cells. However, the role of immune component in osteoarthritis is still poorly investigated. To gain further insights into the interaction of immune cells in OA and the role of adipokines on these cells, we performed experiments aimed to determine the cytokine profile in activated CD4+ T cells from OA patients. For completeness, we also explored the cross talk between T lymphocytes and chondrocytes in OA by co-culturing human primary chondrocytes with activated CD4+ T cells in two ways: the first by incubating the cells by direct contact (D.C.) or by transwell system. Our results show that the exposure of activated CD4+ T cells to adipokines modulates IL-6, IL-8 and CCL-3 production. In addition, the production of key macromolecules of ECM (aggrecan and collagen-2) and matrix metalloproteinase 13 (MMP-13) in co-cultured chondrocytes with activated CD4+ T cells was altered. This article is protected by copyright. All rights reserved
      PubDate: 2016-07-29T16:35:25.84012-05:0
      DOI: 10.1002/jor.23377
       
  • Regional osteoporosis due to osteoclast activation as a trigger for the
           pain-like behaviors in tail-suspended mice
    • Authors: Takayuki Dohke; Kousuke Iba, Megumi Hanaka, Kumiko Kanaya, Yasuhisa Abe, Shunichiro Okazaki, Toshihiko Yamashita
      Abstract: Pathological conditions with refractory skeletal pain are often characterized by regional osteoporotic changes such as transient osteoporosis of the hip, regional migratory osteoporosis or complex regional pain syndrome (CRPS). Our previous study demonstrated that the acidic microenvironment created by osteoclast activation under high bone turnover conditions induced pain-like behaviors in ovariectomized mice through the stimulation of acid-sensing nociceptors. The aim of the present study was to examine whether regional transient osteoporotic changes are related to pain-like behaviors in the hind limb using tail-suspended model mice.The hind limbs of tail-suspended mice were unloaded for 2 weeks, during which time the mice revealed significant regional osteoporotic changes in their hind limbs accompanied by osteoclast activation. In addition, these changes were significantly recovered by the resumption of weight bearing on the hind limbs for 4 weeks. Consistent with the pathological changes in the hind limbs, pain-like behaviors in the mice were induced by tail suspension and recovered by the resumption of weight bearing. Moreover, treatment with bisphosphonate significantly prevented the triggering of the regional osteoporosis and pain-like behaviors, and antagonists of the acid-sensing nociceptors, such as transient receptor potential channel vanilloid subfamily member 1 and acid-sensing ion channels, significantly improved the pain-like behaviors in the tail-suspended mice.We, therefore, believe that regional transient osteoporosis due to osteoclast activation might be a trigger for the pain-like behaviors in tail-suspended model mice. This article is protected by copyright. All rights reserved
      PubDate: 2016-07-19T06:25:35.362163-05:
      DOI: 10.1002/jor.23373
       
  • Reduction of friction by recombinant human proteoglycan 4 in IL-1α
           stimulated bovine cartilage explants
    • Authors: Katherine M. Larson; Ling Zhang, Khaled A. Elsaid, Tannin A. Schmidt, Braden C. Fleming, Gary J. Badger, Gregory D. Jay
      Abstract: A boundary lubricant attaches and protects sliding bearing surfaces by preventing interlocking asperity-asperity contact. Proteoglycan-4 (PRG4) is a boundary lubricant found in the synovial fluid that provides chondroprotection to articular surfaces. Inflammation of the diarthrodial joint modulates local PRG4 concentration. Thus, we measured the effects of inflammation, with Interkeukin-1α (IL-1α) incubation, upon boundary lubrication and PRG4 expression in bovine cartilage explants. We further aimed to determine whether the addition of exogenous human recombinant PRG4 (rhPRG4) could mitigate the effects of inflammation on boundary lubrication and PRG4 expression in vitro.Cartilage explants, following a 7-day incubation with IL-1α, were tested in a disc-on-disc configuration using either rhPRG4 or saline (PBS control) as a lubricant. Following mechanical testing, explants were studied immunohistochemically or underwent RNA extraction for RT-PCR. We found that static coefficient of friction (COF) significantly decreased to 0.14 ± 0.065 from 0.21 ± 0.059 (p = 0.014) in IL-1α stimulated explants lubricated with rhPRG4, as compared to PBS. PRG4 expression was significantly up regulated from 30.8 ± 19 copies in control explants lubricated with PBS to 3330 ± 1760 copies in control explants lubricated with rhPRG4 (p 
      PubDate: 2016-07-13T14:01:28.105964-05:
      DOI: 10.1002/jor.23367
       
  • A clinical platform for understanding the relationship between joint
           contact mechanics & articular cartilage changes after meniscal surgery
    • Authors: Suzanne Maher; Hongsheng Wang, Matthew F. Koff, Nicole Belkin, Hollis G. Potter, Scott Rodeo
      Abstract: Injury to the meniscus of the knee has been implicated as a significant risk factor for the subsequent development of osteoarthritis, but the mechanisms of joint degeneration are unclear. Our objective was to develop a clinically applicable methodology to evaluate the relationship of joint contact mechanics at the time of surgery to biological changes of articular cartilage as a function of time following surgery. A series of pre-, intra- and post-operative protocols were developed which utilized electronic sensors for the direct measurement of contact mechanics, and advanced imaging to assess cartilage health. The tests were applied to a pilot cohort of young active patients undergoing meniscus allograft transplantation. Our study demonstrated significant variability across patients in terms of contact area and peak contact stress, both before and after transplantation. Nonetheless, the majority of patients exhibited decreased peak contact stress and increased contact area after graft implantation. MR scans at 3 to 6 months showed decreased T1ρ values in tibial articular cartilage, suggesting an increase in proteoglycan content or concomitant decrease in water content. Prolongation of T2 values was found primarily within the central, cartilage-cartilage contact region of the tibial plateau suggested disruption of the collagen network. Minimal differences were found in cartilage thickness over the short time frame of this preliminary study. With longer clinical follow-up, our platform of clinical tests can be used to better understand the patient-specific mechanical factors that are related to increased risk of OA after meniscus injury and surgery. This article is protected by copyright. All rights reserved
      PubDate: 2016-07-13T13:55:31.070498-05:
      DOI: 10.1002/jor.23365
       
  • Analysis of polyethylene wear of reverse shoulder components: A validated
           technique and initial clinical results
    • Authors: Kathleen A. Lewicki; John-Erik Bell, Douglas W. Van Citters
      Abstract: One of the most prevalent phenomena associated with reverse total shoulder arthroplasty (rTSA) is scapular notching. Current methods examine only the damage to the scapula and no methods are available for quantifying the total wear volume of the polyethylene humeral bearing. Quantifying the polyethylene material loss may provide insight into the mechanism for scapular notching and into the particle dose delivered to the patient. A coordinate measurement machine (CMM) and custom computer algorithms were employed to quantify the volumetric wear of polyethylene humeral bearings. This technique was validated using two never-implanted polyethylene humeral liners with a controlled amount of wear in clinically relevant locations. The technique was determined to be accurate to within 10% of the known value and within 5 mm3 of the gravimetrically determined values. Following validation, ten retrieved polyethylene humeral liners were analyzed to determine a baseline for future clinical tests. Four of the ten polyethylene humeral liners showed visible and measureable wear volumes ranging from 40 mm3 to 90 mm3 total with a maximum wear rate as high as 470 mm3/year in one short duration and significantly damaged humeral liner. This validated technique has the potential to relate patient outcomes such as scapular notching grades to polyethylene release into the body. While the total wear volumes are less than reported in literature for cases of osteolysis in knee and hip patients, dosages are well within the osteolytic thresholds that have been suggested, indicating that osteolysis may be a clinical concern in the shoulder. This work provides the basis for future studies that relate volumetric wear to patient outcomes. This article is protected by copyright. All rights reserved
      PubDate: 2016-06-27T06:50:29.919903-05:
      DOI: 10.1002/jor.23353
       
  • Timing of mesenchymal stem cell delivery impacts the fate and therapeutic
           potential in intervertebral disc repair
    • Authors: Robert Maidhof; Asfi Rafiuddin, Farzana Chowdhury, Timothy Jacobsen, Nadeen O. Chahine
      Abstract: Cell-based therapies offer a promising approach to treat intervertebral disc (IVD) degeneration. The impact of the injury microenvironment on treatment efficacy has not been established. This study used a rat disc stab injury model with administration of mesenchymal stromal cells (MSCs) at 3, 14, or 30 days post injury (dpi) to evaluate the impact of interventional timing on IVD biochemistry and biomechanics. We also evaluated cellular localization within the disc with near infrared imaging to track the time and spatial profile of cellular migration after in vivo delivery. Results showed that upon injection into a healthy disc, MSCs began to gradually migrate outwards over the course of 14 days, as indicated by decreased signal intensity from the disc space and increased signal within the adjacent vertebrae. Cells administered 14 or 30 dpi also tended to migrate out 14 days after injection but cells injected 3dpi were retained at a significantly higher amount versus the other groups (p 
      PubDate: 2016-06-23T06:55:25.645421-05:
      DOI: 10.1002/jor.23350
       
  • Contrast-enhanced CT imaging as a non-destructive tool for ex vivo
           examination of the biochemical content and structure of the human meniscus
           
    • Authors: Daniel J Oh; Benjamin A Lakin, Rachel C Stewart, Martin Wiewiorski, Jonathan D Freedman, Mark W Grinstaff, Brian D Snyder
      Abstract: The biochemical and histopathological techniques used to investigate meniscal content and structure are destructive and time-consuming. Therefore, this study evaluated whether contrast-enhanced computed tomography (CECT) attenuation and contrast agent flux using the iodinated contrast agents CA4+ and ioxaglate correlate with the glycosaminoglycan (GAG) content/distribution and water content in human menisci. The optimal ioxaglate and CA4+ contrast agent concentrations for mapping meniscal GAG distribution were qualitatively determined by comparison of CECT color maps with Safranin-O stained histological sections. The associations between CECT attenuation and GAG content, CECT attenuation and water content, and flux and water content at various time points were determined using both contrast agents. Depth-wise analyses were also performed through each of the native surfaces to examine differences in contrast agent diffusion kinetics and equilibrium partitioning. The optimal concentrations for GAG depiction for ioxaglate and CA4+ were ≥80 mgI/mL and 12 mgI/mL, respectively. Using these concentrations, weak to moderate associations were found between ioxaglate attenuation and GAG content at all diffusion time points (1–48 hrs), while strong and significant associations were observed between CA4+ attenuation and GAG content as early as 7 hours (R2≥0.67), being strongest at the equilibrium time point (48 hrs, R2 = 0.81). CECT attenuation for both agents did not significantly correlate with water content, but CA4+ flux correlated with water content (R2 = 0.56-0.64). CECT is a promising, non-destructive imaging technique for ex vivo assessment of meniscal GAG concentration and water content compared to traditional biochemical and histopathological methods. This article is protected by copyright. All rights reserved
      PubDate: 2016-06-15T07:15:31.983212-05:
      DOI: 10.1002/jor.23337
       
  • Time-dependent loss of mitochondrial function precedes progressive
           histologic cartilage degeneration in a rabbit meniscal destabilization
           model
    • Authors: Jessica E. Goetz; Mitchell C. Coleman, Douglas C. Fredericks, Emily Petersen, James A. Martin, Todd O. McKinley, Yuki Tochigi
      Abstract: The goals of this work were to characterize progression of osteoarthritic cartilage degeneration in a rabbit medial meniscus destabilization (MMD) model and then to use the model to identify pre-histologic disruptions in chondrocyte metabolism under chronically elevated joint contact stresses in vivo. To characterize PTOA progression, 24 rabbits received either MMD or sham surgery. Limb loading was analyzed preoperatively and at regular postoperative intervals using a Tekscan pressure-sensitive walkway. Animals were euthanized 8 (n = 8 MMD; n = 8 sham) or 26 weeks (n = 8 MMD) postoperatively for histological cartilage evaluation by an objective, semi-automated Mankin scoring routine. To examine pre-histologic pathology, MMD was performed on an additional 20 rabbits, euthanized one (n = 9) or four weeks (n = 10) postoperatively. Chondrocytes were harvested fresh for measurement of mitochondrial function, an intracellular indicator of pathology after mechanical injury. Both MMD and sham surgery caused slight decreases in limb loading which returned to preoperative levels after 2 weeks. Histologically apparent cartilage damage progressed from 8 to 26 weeks after MMD. Changes in chondrocyte respiration were variable at 1 week, but by 4 weeks postoperatively chondrocyte mitochondrial function was significantly reduced. This article is protected by copyright. All rights reserved
      PubDate: 2016-06-09T08:25:50.587963-05:
      DOI: 10.1002/jor.23327
       
  • Use of pre-clinical surgically induced models to understand biomechanical
           and biological consequences of PTOA development
    • Authors: Kristen I Barton; Mehdi Shekarforoush, Bryan J Heard, John L Sevick, Paria Vakil, Mohammad Atarod, C Ryan Martin, Yamini Achari, David A Hart, Cyril B Frank, Nigel G Shrive
      Abstract: Post-traumatic osteoarthritis (PTOA) development is often observed following traumatic knee injuries involving key stabilising structures such as the cruciate ligaments or the menisci. Both biomechanical and biological alterations that follow knee injuries have been implicated in PTOA development, although it has not been possible to differentiate clearly between the two causal factors. This review critically examines the outcomes from pre-clinical lapine and ovine injury models arising in the authors' laboratories and differing in severity of PTOA development and progression. Specifically, we focus on how varying severity of knee injuries influence the subsequent alterations in kinematics, kinetics, and biological outcomes. The immediate impact of injury on the lubrication capacity of the joint is examined in the context of its influence on biomechanical alterations, thus linking the biological changes to abnormal kinematics, leading to a focus on the potential areas for interventions to inhibit or prevent development of the disease. We believe that PTOA results from altered cartilage surface interactions where biological and biomechanical factors intersect, and mitigating acute joint inflammation may be critical to prolonging PTOA development. This article is protected by copyright. All rights reserved
      PubDate: 2016-06-03T06:59:27.633526-05:
      DOI: 10.1002/jor.23322
       
  • Role of miR-155 in the regulation of MMP-16 expression in intervertebral
           disc degeneration
    • Authors: Wei-Lin Zhang; Yu-Fei Chen, Hong-Zheng Meng, Jun-Jie Du, Guan-Nan Luan, Hai-Qiang Wang, Mao-Wei Yang, Zhuo-Jing Luo
      Abstract: The molecular mechanisms of intervertebral disc degeneration (IDD) remain elusive. We found that miR-155 is down-regulated in degenerative nucleus pulposus (NP), and more severe degeneration is correlated with higher matrix metallopeptidase 16 (MMP-16) expression. MMP-16 also degraded matrix aggrecan. Here, we addressed the in vivo miR-155-mediated pathological impact on IDD using a classic puncture mouse model. Lentiviral upregulated-miR-155 or downregulated-miR-155 was transduced into the discs of C57 mice, which was validated by real-time polymerase chain reaction (real-time PCR) and in situ hybridization. Immunohistochemistry and western blotting revealed that up-regulation of miR-155 resulted in down-regulation of MMP-16 and an increase in aggrecan and collagen type II in mouse NP; whereas, down-regulation of miR-155 resulted in up-regulation of MMP-16 and a decrease in aggrecan in mouse NP. Radiographic and histological analysis showed that the up-regulation of miR-155 attenuated IDD, while down-regulation of miR-155 resulted in the deterioration of IDD. These findings indicate that decreased miR-155 contributed to the up-regulation of MMP-16 in vivo, and MMP-16 further degraded aggrecan and collagen type II, leading to the dehydration and degeneration of discs. Our findings revealed a therapeutic role for miR-155 in IDD. This article is protected by copyright. All rights reserved
      PubDate: 2016-05-26T12:25:40.317909-05:
      DOI: 10.1002/jor.23313
       
  • Increased sorbitol levels in the hypertrophic ligamentumflavum of diabetic
           patients with lumbar spinal canal stenosis
    • Authors: Jiaquan Luo; Lu Huang, Zhuo Chen, Zhaoxun Zeng, Takeshi Miyamoto, Hao Wu, Zhongzu Zhang, Zhimin Pan, Nobuyuki Fujita, Tomohiro Hikata, Akio Iwanami, Takashi Tsuji, Ken Ishii, Masaya Nakamura, Morio Matsumoto, Kota Watanabe, Kai Cao
      Abstract: The pathomechanism of the ligamentumflavum (LF) hypertrophy in diabetic patients with lumbar spinal canal stenosis (LSCS) remains unclear.A cross-sectional study was undertaken to investigate the mechanism of LF hypertrophy in thesepatients. Twenty-four diabetic and 20normoglycemic patients with LSCS were enrolled in the study. The structure of the LF in the study subjects was evaluated using histological and immunohistochemicalmethods, and thelevels of sorbitol, pro-inflammatory cytokines, and the fibrogenicfactor, TGF-β1,in the LF were analyzed.In vitro experiments were performed using NIH3T3 fibroblasts to evaluate the effect of high-glucoseconditions and an aldose reductase inhibitoron the cellular production ofsorbitol, pro-inflammatory factors, and TGF-β1. We found that the LF of diabetic patients exhibited significantly higher levels of sorbitol and pro-inflammatory cytokines, TGF-β1and of CD68-positive staining than that of the normoglycemic subjects. The diabetic LF was significantly thickerthan that of the controls, and showed evidence of degeneration. The high glucose-cultured fibroblasts exhibited significantly higher levels of sorbitol, pro-inflammatory factors, and TGF-β1compared to the low glucose-cultured cells, and these levels were dose-dependently reduced by treatment with the aldose reductase inhibitor.Taken together, our data suggests that increased sorbitol levels in the LF of diabetic patientsresults in increased production of pro-inflammatory and fibrogenicfactor, which contribute to LF hypertrophy, and could increase the susceptibility of diabetic patients to LSCS. Furthermore, aldose reductase inhibition effectively reduced the levels of sorbitol and sorbitol-induced pro-inflammatory factor expression in high glucose-cultured fibroblasts. This article is protected by copyright. All rights reserved
      PubDate: 2016-05-21T16:05:37.609222-05:
      DOI: 10.1002/jor.23302
       
  • Intra-articular dexamethasone to inhibit the development of post-traumatic
           osteoarthritis
    • Authors: Alan J. Grodzinsky; Yang Wang, Sanjeev Kakar, Mark S. Vrahas, Christopher H. Evans
      Abstract: Injury to the joint provokes a number of local pathophysiological changes, including synthesis of inflammatory cytokines, death of chondrocytes, breakdown of the extra-cellular matrix of cartilage and reduced synthesis of matrix macromolecules. These processes combine to engender the subsequent development of post-traumatic osteoarthritis (PTOA). To prevent this from happening, it is necessary to inhibit these disparate responses to injury; given their heterogeneity, this is challenging. However, dexamethasone has the necessary pleiotropic properties required of a drug for this purpose. Using in vitro models, we have shown that low doses of dexamethasone sustain the synthesis of cartilage proteoglycans while inhibiting their breakdown after injurious compression in the presence or absence of inflammatory cytokines. Under these conditions, dexamethasone is non-toxic and maintains the viability of chondrocytes exposed chronically to such cytokines as interleukin (IL) -1, IL-6 and tumor necrosis factor-α. Moreover, the anti-inflammatory properties of dexamethasone have been appreciated for decades. In view of this information, we have initiated a pilot clinical study to determine whether a single, intra-articular injection of dexamethasone into the wrist shows promise in preventing PTOA after intra-articular fracture of the distal radius. This article is protected by copyright. All rights reserved
      PubDate: 2016-05-13T16:00:27.37435-05:0
      DOI: 10.1002/jor.23295
       
  • Dual growth factor delivery from biofunctionalized allografts: Sequential
           VEGF and BMP-2 release to stimulate allograft remodeling
    • Authors: Farzana Sharmin; Casey McDermott, Jay Lieberman, Archana Sanjay, Yusuf Khan
      Abstract: Autografts have been shown to stimulate osteogenesis, osteoclastogenesis and angiogenesis, and subsequent rapid graft incorporation. Large structural allografts, however, suffer from limited new bone formation and remodeling, both of which are directly associated with clinical failure due to non-unions, late graft fractures, and infections, making it a priority to improve large structural allograft healing. We have previously shown the osteogenic ability of a polymer-coated allograft that delivers bone morphogenetic protein-2 both in vitro and in vivo through both burst release and sustained release kinetics. In this study, we have demonstrated largely sequential delivery of bone morphogenetic protein-2 and vascular endothelial growth factor from the same coated allograft. Release data showed that loading both growth factors onto a polymeric coating with two different techniques resulted in short term (95% release within 2 weeks) and long term (95% release within 5 weeks) delivery kinetics. We have also demonstrated how released VEGF, traditionally associated with angiogenesis, can also provide a stimulus for allograft remodeling via resorption. Bone marrow derived mononuclear cells were co-cultured with VEGF released from the coated allograft and showed a statistically significant (p 
      PubDate: 2016-05-07T17:35:26.870077-05:
      DOI: 10.1002/jor.23287
       
  • High fat diet accelerates cartilage repair in DBA/1 mice
    • Authors: Wu Wei; Yvonne M. Bastiaansen-Jenniskens, Mathijs Suijkerbuijk, Nicole Kops, Pieter K. Bos, Jan A.N. Verhaar, Anne-Marie Zuurmond, Francesco Dell'Accio, Gerjo J.V.M. van Osch
      Abstract: Obesity is a well-known risk factor for osteoarthritis, but it is unknown what it does on cartilage repair. Here we investigated whether a high fat diet (HFD) influences cartilage repair in a mouse model of cartilage repair. We fed DBA/1 mice control or HFD (60% energy from fat). After two weeks, a full thickness cartilage defect was made in the trochlear groove. Mice were sacrificed, 1, 8 and 24 weeks after operation. Cartilage repair was evaluated on histology. Serum glucose, insulin and amyloid A were measured 24h before operation and at endpoints. Immunohistochemical staining was performed on synovium and adipose tissue to evaluate macrophage infiltration and phenotype. One week after operation, mice on HFD had defect filling with fibroblast-like cells and more cartilage repair as indicated by a lower Pineda score. After 8 weeks, mice on a HFD still had a lower Pineda score. After 24 weeks, no mice had complete cartilage repair and we did not detect a significant difference in cartilage repair between diets. Bodyweight was increased by HFD, whereas serum glucose, amyloid A and insulin were not influenced. Macrophage infiltration and phenotype in adipose tissue and synovium were not influenced by HFD. In contrast to common wisdom, HFD accelerated intrinsic cartilage repair in DBA/1 mice on the short term. Resistance to HFD induced inflammatory and metabolic changes could be associated with accelerated cartilage repair. This article is protected by copyright. All rights reserved
      PubDate: 2016-05-04T17:55:30.261547-05:
      DOI: 10.1002/jor.23280
       
  • Role of pulsed electromagnetic fields (PEMF) on tenocytes and
           myoblasts—Potential application for treating rotator cuff tears
    • Authors: Mengyao Liu; Carlin Lee, Dominique Laron, Nianli Zhang, Erik I. Waldorff, James T. Ryaby, Brian Feeley, Xuhui Liu
      Abstract: The post-surgery integrity of the tendons and muscle quality are the two major factors in success of rotator cuff (RC) repair. Though surgical techniques for rotator cuff repair have significantly improved in the past two decades, there are no effective treatments to improve tendon-to-bone healing and muscle quality after repair at this point in time. Pulsed electromagnetic fields (PEMF) have previously been used for promoting fracture healing. Previous studies have shown that PEMF has a positive role in promoting osteoblast precursors proliferation and differentiation. However, PEMFs effect on tenocytes and muscle cells has not been determined fully yet. The purpose of this study is to define the role of a commercially available PEMF on tenocytes and myoblasts growth and differentiation in vitro. Human rotator cuff tenocytes and C2C12 murine myoblasts were cultured and treated with PEMF for 2 weeks under regular and inflammatory conditions. Our results showed that 2 weeks treatment of PEMF enhanced gene expressions of growth factors in human rotator cuff tenocytes under inflammatory conditions. PEMF significantly enhanced C2C12 myotube formation under normal and inflammatory conditions. Results from this study suggest that PEMF has a positive role in promoting tenocyte gene expression and myoblast differentiation. Therefore, PEMF may potentially serve as a non-operative treatment to improve clinical incomes rotator cuff tendon repairs. This article is protected by copyright. All rights reserved
      PubDate: 2016-05-02T13:23:27.528398-05:
      DOI: 10.1002/jor.23278
       
  • Comparative meta-analysis on the various vascularized bone flaps used for
           the treatment of scaphoid non-union
    • Authors: Konstantinos Ditsios; Ioannis Konstantinidis, Konstantinos Agas, Anastasios Christodoulou
      Abstract: We did a meta-analysis of the literature in order to clarify which of the vascularized bone flaps (VBF) used for scaphoid non-union treatment has the best outcome with regard to various parameters. We analyzed 54 articles that present 9 different types of VBF. The analysis concerned demographical patient information, radiographic parameters, fracture classification, including the presence or non-presence of avascular necrosis of the scaphoid proximal pole (PP AVN), parameters that have to do with the surgery itself and the postoperative protocol, the healing of the non-union and functional scores. The meta-analysis showed best healing potential for the femoral graft despite the complexity of the operation. On the other hand, the most-commonly-used 1,2-ICSRA flap makes the procedure more reproducible but showed worse results. The femoral flap was also among the most successful flaps when used for patients with PP AVN. The consolidation rate, in general, wasn't affected by the time elapsed between the fracture and the operation but by smoking and the presence of PP AVN. The meta-analysis couldn't reach many significant statistical conclusions because of either the small number of patients in some flap groups or the heterogeneity and lack of documentation in most of the articles. This article is protected by copyright. All rights reserved
      PubDate: 2016-03-28T06:46:13.895487-05:
      DOI: 10.1002/jor.23242
       
  • The three dimensional microstructural network of elastin, collagen and
           cells in Achilles tendons
    • Authors: Xin Pang; Jian Ping Wu, Garry T Allison, Jiake Xu, Jonas Rubenson, Ming-Hao Zheng, David G Lloyd, Bruce Gardiner, Allan Wang, Thomas Brett Kirk
      Abstract: Similar to most biological tissues, the biomechanical and functional characteristics of the Achilles tendon are closely related to its composition and microstructure. It is commonly reported that type I collagen is the predominant component of tendons and is mainly responsible for the tissue's function. Although elastin has been found in varying proportions in other connective tissues, previous studies report that tendons contain very small quantities of elastin. However, the morphology of and the microstructural relationship among the elastic fibres, collagen and cells in tendon tissue have not been well examined. We hypothesize the elastic fibres, as another fibrillar component in the extracellular matrix, have a unique role in mechanical functions and microstructural arrangement in Achilles tendons. Using confocal and Second Harmonic Generation (SHG) imaging techniques, this study examined the 3-dimensional microstructure of the collagen, elastin and cells in the mid-portion of hydrated rabbit Achilles tendons. It has been shown that elastic fibres present a close connection with the tenocytes. The close relationship of the three components has been revealed as a distinct, integrated and complex microstructural network. Notably, a “spiral” structure within fibril bundles in Achilles tendons was observed in some samples in specialized regions. This study substantiates the hierarchical system of the spatial microstructure of tendon, including the mapping of collagen, elastin and tenocytes, with 3-dimensional confocal images. This article is protected by copyright. All rights reserved
      PubDate: 2016-03-22T12:25:49.620766-05:
      DOI: 10.1002/jor.23240
       
  • Biological responses of osteocytic connexin 43 hemichannels to simulated
           microgravity
    • Authors: Huiyun Xu; Ruofei Liu, Dandan Ning, Jian Zhang, Ruixin Yang, Manuel A Riquelme, Jingbao Li, Jean X. Jiang, Peng Shang
      Abstract: Connexin 43 (Cx43) hemichannels and gap junctions in osteocytes are responsive to mechanical loading, which is important for bone formation and remodeling. However, the mechanism of these Cx43-forming channels in the process of mechanical unloading is still not very clear. In this study, unloading caused by weightlessness was simulated by using a random position machine (RPM). Osteocytic MLO-Y4 cells were subjected to 2 hrs of RPM treatment, and levels of Cx43 mRNA and total and cell surface expressed protein were determined by quantitative real-time PCR, western blotting and biotinylation analysis. Although mRNA was elevated by RPM, total protein level of Cx43 was not altered; however, surface biotinylated Cx43 was significantly reduced. Interestingly, RPM promoted the retention of Cx43 in the Golgi apparatus detected by co-immunofluorescence with antibodies against Cx43 and 58K Golgi marker protein. Dye uptake assay showed that hemichannels were induced open after RPM for 2 hrs. Consistently, prostaglandin E2 release was increased and this increase was completely attenuated with the treatment of a Cx43 hemichannel blocking antibody. Together, this study demonstrates increased activity of Cx43 hemichannels to RPM, and active Cx43 hemichannels with prostaglandin E2 release are likely to module biological function under simulated weightless conditions. This article is protected by copyright. All rights reserved
      PubDate: 2016-03-04T10:59:46.901273-05:
      DOI: 10.1002/jor.23224
       
  • Local delivery of zoledronate from a poly (D,L-lactide)-coating increases
           fixation of hydroxy-coated implants
    • Authors: Thomas Jakobsen; Joan E. Bechtold, Kjeld Søballe, Thomas Jensen, Marianne T. Vestermark, Jørgen Baas
      Abstract: Initial secure implant fixation predicts long-term survival. Bisphosphonates are anti-resorptive agents. They have been shown to increase implant fixation. We investigated whether local delivery of zoledronate from a poly-D,L-lactide (PDLLA)-coating could improve fixation and osseointegration of hydroxy-apatite coated implants. Cylindrical hydroxy-apatite coated implants were bilaterally inserted press-fit into the proximal tibiae of 10 dogs. On one side the implant was coated with PDLLA containing zoledronate. The PDLLA coating was applied upon the hydroxy-apatite coating. We used the contralateral implant as control. This implant was not coated with a poly-D,L-lactide. Observation period was 12 weeks. We evaluated implant fixation with histomorphometry and biomechanical push-out test. Zoledronate resulted in an approximately 3-fold increase in all biomechanical parameters when comparing data with their respective controls. We found that zoledronate increased preservation of old lamellar bone and increased formation of new woven bone. This study indicates that local delivery of zoledronate from a PDDLA coating has the potential to increase implant fixation. Studies investigating different doses of zoledronate and longer follow-up are needed. This article is protected by copyright. All rights reserved
      PubDate: 2016-03-01T07:08:38.187149-05:
      DOI: 10.1002/jor.23219
       
  • Transplantation of autologous synovial mesenchymal stem cells promotes
           meniscus regeneration in aged primates
    • Authors: Shimpei Kondo; Takeshi Muneta, Yusuke Nakagawa, Hideyuki Koga, Toshifumi Watanabe, Kunikazu Tsuji, Shinichi Sotome, Atsushi Okawa, Shinji Kiuchi, Hideo Ono, Mitsuru Mizuno, Ichiro Sekiya
      Abstract: Transplantation of aggregates of synovial mesenchymal stem cells (MSCs) enhanced meniscus regeneration in rats. Anatomy and biological properties of the meniscus depend on animal species. To apply this technique clinically, it is valuable to investigate the use of animals genetically close to humans. We investigated whether transplantation of aggregates of autologous synovial MSCs promoted meniscal regeneration in aged primates. Chynomolgus primates between 12-13 years old were used. After the anterior halves of the medial menisci in both knees were removed, an average of 14 aggregates consisting of 250,000 synovial MSCs were transplanted onto the meniscus defect. No aggregates were transplanted to the opposite knee for the control. Meniscus and articular cartilage were analyzed macroscopically, histologically, and by MRI T1rho mapping at 8 (n = 3) and 16 weeks (n = 4). The medial meniscus was larger and the modified Pauli's histological score for the regenerated meniscus was better in the MSC group than in the control group in each primate at 8 and 16 weeks. Mankin's score for the medial femoral condyle cartilage was better in the MSC group than in the control group in all primates at 16 weeks. T1rho value for both the regenerated meniscus and adjacent articular cartilage in the MSC group was closer to the normal meniscus than in the control group in all primates at 16 weeks. Transplantation of aggregates of autologous synovial MSCs promoted meniscus regeneration and delayed progression of degeneration of articular cartilage in aged primates. This is the first report dealing with meniscus regeneration in primates. This article is protected by copyright. All rights reserved
      PubDate: 2016-02-24T15:30:34.802455-05:
      DOI: 10.1002/jor.23211
       
  • Substrain-specific differences in bone parameters, alpha-2-macroglobulin
           circulating levels and osteonecrosis incidence in a rat model
    • Authors: Alberto V. Carli; Edward J. Harvey, Bouziane Azeddine, Chan Gao, Yongbiao Li, Ailian Li, Mireille Sayegh, Huifen Wang, Ayoub Nahal, René P. Michel, Janet E. Henderson, Chantal Séguin
      Abstract: Osteonecrosis of the femoral head (ONFH) is a potentially devastating complication that occurs in up to 40% of young adults receiving chronic glucocorticoid (GC) therapy. Through a validated GC therapy rat model, we have previously shown that Wistar Kyoto (WK) rats exhibit a genetic susceptibility to GC-induced ONFH compared to Sasco Fischer (F344) rats. We have undertaken this study in order to investigate differences between these two strains for their bone parameters, alpha-2-macroglobulin (A2M) circulating levels and incidence of GC-induced osteonecrosis of the femoral head. WK and F344 rats were treated either with 1.5mg/kg/day of prednisone or placebo for six months. Blood was taken every month. The femoral heads were harvested for histological examination to detect ONFH and analyzed with micro-computed tomography. After three months of GC-therapy, plasma A2M was elevated in treated rats only. GC-treated WK rats exhibited histological evidence of early ONFH through higher rates of cellular apoptosis and empty osteocyte lacunae in the subchondral bone compared to placebos and to F344 rats. Furthermore, micro-CT analysis exhibited femoral head collapse only in GC-treated WK rats. Interestingly, GC-treated F344 rats exhibited significant micro-CT changes, but such changes were less concentrated in the articular region and were accompanied histologically with increased marrow fat. These µCT and histological findings suggest that elevated A2M serum level is not predictive and suitable as an indicative biomarker for early GC-induced ONFH in rodents. Elevated A2M levels observed during GC treatment suggests that it plays role in the host reparative response to GC-associated effects. This article is protected by copyright. All rights reserved
      PubDate: 2016-02-19T20:45:22.895958-05:
      DOI: 10.1002/jor.23199
       
  • Clinical evaluation of model-based radiostereometric analysis to measure
           femoral head penetration and cup migration in four different cup designs
    • Authors: Bita Shareghi; Per-Erik Johanson, Johan Kärrholm
      Abstract: In conventional Radiostereometric analysis (RSA) implants with attached tantalum markers are frequently used, which may be difficult to visualize. This problem can be avoided with model-based RSA (MBRSA), but it is uncertain if this method has the same precision as marker-based RSA. We evaluated the influence of cup design for the precision of MBRSA in 4 uncemented cups to study if the design had any influence on the precision. Stereo radiographs were analyzed postoperatively (double-examinations) and after 2 years (single examinations). The difference between the double-examinations was used to compute the precision for the methods and for each type of implant. Femoral head penetration and cup translation up to 2 years were compared using marker-based RSA as reference. The precision of proximal penetration and migration measurements did not differ between the methods for Trilogy, TMT and ABG. For Ringloc design a poorer precision was observed using MBRSA. Comparison between the methods regarding proximal penetration and cup migration at 2 years did not differ for 3 of the designs (p= 0.12-0.91). However, for the group with porous plasma sprayed surface (Ringloc) a significant difference between the methods was observed (ppenetration 
      PubDate: 2016-01-30T06:41:20.933071-05:
      DOI: 10.1002/jor.23177
       
  • Netzwerken für Bauwerksinformationsmodelle BIM,
           Interoperabilität und Co-Simulation
    • Authors: John Grunewald
      Pages: 339 - 339
      PubDate: 2016-12-01T05:22:20.934829-05:
      DOI: 10.1002/bapi.201690057
       
  • A thermal conductivity prediction model for porous building blocks
    • Authors: Wouter Van De Walle; Hans Janssen
      Pages: 340 - 347
      Abstract: A 3D model for the prediction of the effective thermal conductivity of porous building blocks is introduced. Simulations are performed directly on the microstructure using voxel images and the finite element technique. Very good agreement with analytical solutions is achieved. The model is used to investigate the miscalculation effect of 2D simulations, clearly indicating the need for a 3D model. Furthermore, a method for incorporating radiative heat transfer at the microscale is implemented and applied on a synthetic sample, demonstrating the influence of thermal radiation on the effective thermal conductivity.Ein Vorhersagemodell für die Wärmeleitfähigkeit poröser Bausteine. Ein 3D-Modell zur Vorhersage der effektiven Wärmeleitfähigkeit poröser Bausteine wird vorgestellt. Simulationen werden direkt in der Mikrostruktur mittels Voxel-Bildern und Finite-Elemente-Methode durchgeführt. Sehr gute Übereinstimmungen mit analytischen Verfahren werden erreicht. Das Modell wird verwendet, um die Fehlberechnungswirkung von 2D-Simulationen zu untersuchen, welche klar das Erfordernis eines 3D-Modells zeigen. Zudem wird eine Methode zur Einbeziehung strahlungsgebundener Wärmeübertragung im Mikrobereich umgesetzt und auf einen synthetischen Prüfkörper angewandt. Dies zeigt den Einfluss von Wärmestrahlung auf die effektive Wärmeleitfähigkeit.
      PubDate: 2016-12-01T05:22:20.513369-05:
      DOI: 10.1002/bapi.201610037
       
  • Effect of salts and absorption cycles in the capillary coefficient of
           building materials with different joints
    • Authors: Ana S. Guimarães; João M. P. Q. Delgado, Vasco P. de Freitas
      Pages: 348 - 354
      Abstract: Rising damp can reduce building's aesthetical value, comfort and health mark, when combined with the existence of soluble salts in the building components and in the ground water can even lead to material decomposition and compromise its structural performance.This research work intended to study the effect of different absorption cycles of two saturated solutions of sodium sulphate and potassium chloride in the capillary absorption curves obtained through the partial immersion of red brick samples without and with different joints. The results revealed significant differences in the capillary coefficients obtained when samples were tested with salt solutions.Wirkung von Salzen und Absorptionsprozessen auf den Kapillartransportkoeffizienten von Baustoffen mit verschiedenen Fugen. Aufsteigende Feuchte kann den ästhetischen Wert, den Komfort und die Gesundheitswirkung von Gebäuden negativ beeinflussen. Lösliche Salze in den Bauteilen und im Grundwasser können hierbei sogar Zersetzungsprozesse auslösen und die Standsicherheit beeinträchtigen.Diese Forschungsarbeit untersucht die Wirkung unterschiedlicher Absorptionszyklen von gesättigter Natriumsulfat- bzw. Kaliumchlorid-Lösung auf die kapillaren Absorptionskurven. Für den Versuch wurden Prüfkörper aus Backstein mit und ohne Fugen teilweise eingetaucht. Die Ergebnisse zeigten bei Salzlösungen signifikante Unterschiede der Kapillartransportkoeffizienten.
      PubDate: 2016-12-01T05:22:21.014446-05:
      DOI: 10.1002/bapi.201610036
       
  • Results of Belgian quality control framework for cavity wall insulation
    • Authors: Arnold Janssens; Marc Delghust, Nathan Van Den Bossche
      Pages: 355 - 360
      Abstract: Since 2012 a quality control system is in operation in Belgium to provide confidence in the quality of the works of cavity wall insulation in existing walls. When the works are in line with the quality framework, the installer may provide a declaration of conformity to the client, which he can use to receive subsidies or for energy performance certification.A field study was performed to analyze the relationship between the information provided by installers in the declaration of conformity, the results of the conformity checks performed by the certification organization and the effective cavity wall performance measured on site.Ergebnisse der Belgischen Qualitätskontrolle für die nachträgliche Wärmedämmung von Hohlwänden. Seit 2012 ist in Belgien ein System zur Qualitätskontrolle in Betrieb, das Vertrauen in die nachträgliche Wärmedämmung bestehender Wände schaffen soll. Wenn die Arbeiten im Einklang mit dem Qualitätsrahmen erbracht wurden, kann der Ausführungsbetrieb dem Kunden eine Konformitätserklärung ausstellen, die dieser für die Zuteilung von Zuschüssen und für die Ausstellung eines Energieausweises nutzen kann. Es wurde eine Feldstudie durchgeführt, um die Angaben in den Konformitätserklärungen der Ausführungsbetriebe mit den Ergebnissen der Konformitätsprüfung durch die Zertifizierungsgesellschaft und mit den vor Ort gemessenen effektiven Dämmwerten zu vergleichen.
      PubDate: 2016-12-01T05:22:21.109944-05:
      DOI: 10.1002/bapi.201610035
       
  • A new procedure for selecting moisture reference years for hygrothermal
           simulations
    • Authors: Xiaohai Zhou; Dominique Derome, Jan Carmeliet
      Pages: 361 - 365
      Abstract: Hygrothermal models allow designers to evaluate the hygrothermal performance of building envelopes. However, hygrothermal modeling needs the input of the external climate loading, a moisture reference year, to evaluate moisture damage risk of building envelope. In this paper, a new procedure is proposed for selecting moisture reference years. A metric, called Climatic Index, combining wind-driven rain load and potential evaporation is developed in this study. Climatic Indices over 30 years are determined for a wall envelope located in Zurich, Switzerland. The hygrothermal performance of the wall envelope and its moisture damage risk are simulated and evaluated using a hygrothermal risk indicator, called the RHT Index. A clear correlation between Climatic Index and RHT Index is found for the specific moisture damage considered, mold growth. The selection procedure combines a first selection of three years around the 10 % level criterion based on the Climatic Index, followed by a careful comparison of different years based on RHT Index and a final selection of the year with the largest RHT Index as moisture reference year. The combination of Climatic Index and RHT Index allows for the selection of moisture reference years with known level of damage risk.Ein neues Verfahren zur Auswahl von Feuchte-Referenzjahren für hygrothermische Simulationen. Hygrothermische Modelle ermöglichen es Planern, die hygrothermischen Eigenschaften der Gebäudehülle zu bewerten. Zur Bewertung des Risikos von Feuchteschäden sind für die hygrothermische Modellierung Daten zur äußeren klimatischen Belastung erforderlich, und zwar in Form eines Feuchte-Referenzjahres. Der vorliegende Beitrag schlägt ein neues Verfahren zur Auswahl von Feuchte-Referenzjahren vor. In der Studie wird eine Maßzahl namens “Klimatischer Index” entwickelt, die windbasierte Regenlast und potenzielle Verdunstung kombiniert. Klimatische Indexwerte für 30 Jahre werden für eine Außenwand in Zürich (Schweiz) bestimmt. Das hygrothermische Verhalten der Außenwand sowie ihr Risiko von Feuchteschäden werden simuliert und bewertet anhand eines hygrothermischen Risikoindikators, genannt RHT-Index. Für die hier speziell betrachtete Art von Feuchteschäden, den Schimmelbefall, wird ein eindeutiger Zusammenhang zwischen Klimatischem Index und RHT-Index ermittelt. Das Verfahren umfasst eine erste Auswahl von drei Jahren basierend auf einem 10%-Kriterium und dem Klimatischen Index, dem dann ein sorgfältiger Vergleich verschiedener Jahre auf Grundlage des RHT-Index folgt und schließlich die Auswahl jenes Jahres mit dem höchsten RHT-Index als Feuchte-Referenzjahr. Die Kombination von Klimatischem Index und RHT-Index ermöglicht die Auswahl von Feuchte-Referenzjahren mit bekanntem Schadensrisiko.
      PubDate: 2016-12-01T05:22:21.614824-05:
      DOI: 10.1002/bapi.201610042
       
  • Modeling damage of building materials induced by sodium sulphate
           crystallization
    • Authors: Marcin Koniorczyk; Dariusz Gawin, Piotr Konca, Dalia Bednarska
      Pages: 366 - 371
      Abstract: One of the most adverse phenomena which is related to salt and moisture presence in the pore system of building materials is salt crystallization. The microstructure analysis (using mercury intrusion porosimetry) of cement mortar samples due to cyclic salt crystallization is analyzed. We assume that salt crystals grow only from the supersaturated solution. The salt phase change kinetics is taken into account during the modelling of coupled moisture, salt and heat transport. To solve the set of governing, partial differential equations the finite element and finite difference methods are used. The drying and the cooling – warming of brick wall, during which the salt phase change occurs, have been simulated using the developed software. The changes of salt concentration in the pore solution and the amount of precipitated salt due to variation of boundary conditions are calculated and discussed.Modellierung von Schäden an durch Natriumsulfat-Kristallisation. Eines der nachteiligsten Phänomene im Zusammenhang mit Salz und Feuchtigkeit im Porensystem von Baustoffen ist die Salzkristallisation. Die Veränderung der Mikrostruktur von Zementmörtel-Prüfkörpern durch zyklische Salzkristallisation wird analysiert (mittels Quecksilber Intrusions-Porosimetrie). Es wird vorausgesetzt, dass Salzkristalle nur aus übersättigter Lösung wachsen. Die Kinetik der Phasenänderung des Salzes wird bei der Modellierung des gekoppelten Feuchte-, Wärme- und Salztransports berücksichtigt. Die zugrunde liegenden partiellen Differentialgleichungen werden mittels Finite-Elemente- und Finite-Differenzen-Methoden gelöst. Die Trocknung und Kühlung bzw. Erwärmung einer Ziegelwand, während welcher der Salz-Phasenwechsel erfolgt, wurden mittels der entwickelten Software simuliert. Die Änderungen der Salzkonzentration in der Porenlösung und die Mengenänderung des Salzniederschlags durch Variation der Randbedingungen werden berechnet und diskutiert.
      PubDate: 2016-12-01T05:22:21.716232-05:
      DOI: 10.1002/bapi.201610041
       
  • Modeling low temperature district heating networks for the utilization of
           local energy potentials
    • Authors: Karl Martin Heissler; Laura Franke, Isabell Nemeth, Thomas Auer
      Pages: 372 - 377
      Abstract: In this paper a modeling approach for the simulation of a low temperature district heating network with seasonal heat storage, collectors and buildings is presented. The approach combines the strengths of the simulation environments Dymola and TRNSYS through the tool “Building Controls Virtual Testbed” to a simulation framework. It is capable of simulating alternating flow conditions within a detailed pipe network along with the heat demand and supply of network-connected buildings and solar collectors. An ecological model settlement in Munich serves as case study for the framework.Modellierung von Niedrigtemperaturnetzen zur Nutzung lokaler Energiepotenziale in Quartieren. Dieser Beitrag stellt einen Modellierungsansatz für die Simulation eines Niedrigtemperaturnetzes mit saisonalem Wärmespeicher, Solarkollektoren und Gebäuden vor. Der Ansatz vereint die Stärken der Simulationsumgebungen Dymola und TRNSYS durch das Tool “Building Controls Virtual Testbed” zu einer Co-Simulationsumgebung. Diese ist in der Lage, wechselnde Strömungsrichtungen innerhalb eines detaillierten Rohrnetzes und Wärmeangebot und -bedarf der an das Netz angebundenen Gebäude und Solarkollektoren abzubilden. Eine “Ökologische Mustersiedlung” in München dient als Fallbeispiel.
      PubDate: 2016-12-01T05:22:21.24367-05:0
      DOI: 10.1002/bapi.201610038
       
  • Nachwuchsinnovationspreis Bauwerkserhaltung für Absolventin der
           Bauhaus-Uni Weimar
    • Pages: 377 - 377
      PubDate: 2016-12-01T05:22:20.723716-05:
      DOI: 10.1002/bapi.201690048
       
  • Fallstudie zum Trocknungsverhalten von Außenwandkonstruktionen aus
           Porenbeton mit Wärmedämmverbundsystem
    • Authors: Anna Vašková; Marián Vertal', Dušan Katunský, Azra Korjenic
      Pages: 378 - 388
      Abstract: Die Zahlen der “nicht fertiggestellten Häuser” in der Slowakei, die in den Anzeigen der Immobilienwirtschaft zu Verkauf angeboten werden, steigen rapide an. Die Rohbauten stehen oft Jahre lang vor Witterung ungeschützt, bevor sich ein Käufer findet und sie fertigstellt. Die Fertigstellung passiert dann ziemlich schnell, sodass sich innerhalb kurzer Zeit die Feuchteschäden zeigen, die wiederrum jahrelang Probleme für die Bewohner verursachen. Das meistverwendete Baumaterial hierfür ist Porenbeton. Im Rahmen eines Forschungsprojekts wurden verschiedenste messtechnische und rechnerische Untersuchungen durchgeführt, um die hygrothermische Situation dieser Bauteile darzustellen bzw. einen Leitfaden zur notwendigen Trocknungszeit für die meisten Fertigstellungssituationen auszuarbeiten. Für die messtechnischen Untersuchungen wurde ein Prüfstand hergestellt, an dem verschiedene Konstruktionsvarianten unter realen Klimadaten des Standorts Košice detailliert untersucht wurden. Die rechnerischen Untersuchungen wurden mit dem Simulationsprogramm WUFI durchgeführt.Die Ergebnisse zeigen, dass die Porenbetonwand mit dem EPS-System 28 Monate trocknen muss, um die Bezugsfeuchte w80 zu erreichen. Die reduzierte Trocknung wirkt sich negativ auf den U-Wert und somit auch auf den Wärmeschutz der Baukonstruktion aus. Die durchschnittliche Abweichung des effektiven U-Wertes vom Projektierten hatte in der zweiten Heizperiode 20 % Unterschied ergeben. Während des dritten Winters war sie sogar immer noch mehr als 5 %. Die Orientierung und die verschiedenen Dicken der Wärmedämmung auf EPS-Basis haben einen vernachlässigbaren Einfluss auf das Trocknungsverhalten. Die Verwendung von Mineralwolldämmstoff anstatt EPS verkürzt die Austrocknungszeit um etwa die Hälfte.Die numerische Analyse zeigt, dass nach einer zweimonatigen Trocknung des Porenbetons vor der Applikation eines EPS-Wärmedämmverbundsystems, der durchschnittliche Wassergehalt um 33 % des ursprünglichen Wertes gesenkt wird. Wenn die EPS-Dämmung erst nach fünf Monaten angebracht wird, verkürzt sich die Trocknungszeit auf 14 Monate, so dass sie im Bereich des Mineralwoll-WDVS liegt.Case study investigations on drying process cellular concrete external walls with ETCIS. The number of “not completed buildings” which are offered to be sold increase rapidly. The building shells are exposed to the weather without protection. Sometimes it takes years until the building shells are sold and the construction can be continued. The new owners usually push on the construction very fast. This causes moisture damage. Mostly cellular concrete is the used material. Within the framework of a research project different measurements and calculations were done to constitute the hygrothermic conditions of the components. In addition to that a guideline was written. It contains the minimum time that is necessary to dry all components of the buildings for the most situations. For the investigations a test bench had been built. Different scenarios of the constructions could be tested under real climate conditions of the locations Košice. The scenarios were investigated and the measured data was analysed. The analyses were executed with the simulation program WUFI.The results show that the cellular concrete in combination with the EPS-System needs 28 months to reach the reference humidity w80. The moister effects the u-value of the construction in a negative way. The heat resistance is lower because of the wetness. The averaged influence of the humidity on the effective u-value from the calculated u-value was 20 % in the second heat period. In the third heat period the effective u-value was more than 5 % worse as the calculated. The orientation of the construction and the different thicknesses have a very low influence on the drying process. It is not significant. When mineral wool is used instead of EPS the drying time can be reduced around 50 %.Numeric analyses show that after two months of drying the cellular concrete in combination with EPS reduces the water content by 33 %. When the EPS is installed five months later, the drying time can be reduced by 14 months. This results the same drying time as the mineral wool construction.
      PubDate: 2016-12-01T05:22:20.596633-05:
      DOI: 10.1002/bapi.201610040
       
  • BIM-Leitfaden für die Planungspraxis des VBI
    • Pages: 388 - 388
      PubDate: 2016-12-01T05:22:20.316389-05:
      DOI: 10.1002/bapi.201690049
       
  • Messtechnische Bestimmung von Aufwandszahlen unterschiedlicher
           Flächentemperiersysteme
    • Authors: Jens Pfafferott; Sascha Himmelsbach, Tobias Lang, Mario Frietsch
      Pages: 389 - 399
      Abstract: Mit der Messung des Wärme- und Kälteverbrauchs im Labor gelingt es, sowohl thermisch träge als auch agile Flächentemperiersysteme unter praxisnahen, dynamischen Bedingungen messtechnisch zu bewerten. Werden Nutzwärme- und Nutzkältebedarf berechnet und ins Verhältnis zu den gemessenen Verbräuchen gesetzt, können die Aufwandzahlen für die Nutzenübergabe ece für verschiedene Flächentemperiersysteme und in Kombinationen mit anderen Übergabesystemen unter verschiedenen Nutzungsbedingungen und für unterschiedliche Betriebsführungsstrategien bestimmt werden. Damit stehen Aufwandszahlen auf Basis kalorischer Messungen zur Verfügung, die je nach Aufgabenstellung entweder produkt- oder objektbezogen in der Planung komplexer Energiekonzepte verwendet werden können und die tatsächlichen Aufwandszahlen eh, ce für den Heizfall bzw. ec, ce für den Kühlfall genauer als Literaturwerte bzw. projektbezogen beschreiben.Measurement of energy expenditure factors of various radiant heating and cooling systems. The measurement of heating/cooling consumption is used to evaluate both thermally inert and agile radiant heating and cooling systems under realistic, dynamic conditions in a laboratory. If the net heating/cooling energy demand is calculated, the ratio between calculated demand and measured consumption defines the energy expenditure factor for the heat transfer ece. Thus, ece can be determined under different conditions of use and for different operation strategies and in combination with other heat transfer systems. This provides energy expenditure factors based on caloric measurement which are available either product or object specific. The actual energy expenditure factors eh, ce for the heating mode or ec, ce for the cooling mode can be used in the planning of complex energy concepts since these specific values are more accurate than literature values.
      PubDate: 2016-12-01T05:22:20.371797-05:
      DOI: 10.1002/bapi.201610039
       
  • Ulrich Finsterwalder Ingenieurbaupreis 2017
    • Authors: Dirk Jesse
      Pages: 400 - 403
      PubDate: 2016-12-01T05:22:19.97698-05:0
      DOI: 10.1002/bapi.201690050
       
  • Persönliches: Bauphysik 6/2016
    • Pages: 404 - 405
      Abstract: Trauer um Professor Josef SchmidSebastian Fiedler Professor für Bauphysik und Technischer AusbauHartwig M. Künzel Honorarprofessor an der Universität Stuttgart
      PubDate: 2016-12-01T05:22:21.343543-05:
      DOI: 10.1002/bapi.201690051
       
  • Aktuell: Bauphysik 6/2016
    • Pages: 405 - 410
      Abstract: Neuer Verband “Bundesverband energieeffiziente Gebäudehülle” / Aktuelle Studie: Energiesparhäuser müssen nicht teurer sein / Offener Brief der Umwelt- und Energieminister an BMUB und BMWi zur Novellierung des gebäudebezogenen Energieeinsparrechts / 38. Deutscher Stahlbautag 2016 und Preis des Deutschen Stahlbaus / 1. Kongress Energie Effizienz Bauen – Neue Konzepte und innovative Technologien aus der Forschung / Feuerprobe: weltweit größte Brandprüfung eines Brandschutzglases
      PubDate: 2016-12-01T05:22:20.117235-05:
      DOI: 10.1002/bapi.201690052
       
  • Technische Regelsetzung: Bauphysik 6/2016
    • Pages: 410 - 411
      Abstract: VDI 6020 fasst Anforderungen an Rechenverfahren zur instationären thermisch-energetischen Gebäudesimulation zusammen / Fenster, Türen und Tore nach EN 16034 für den Brandschutz mit CE-Zeichen ab 1.11.2016
      PubDate: 2016-12-01T05:22:21.822263-05:
      DOI: 10.1002/bapi.201690053
       
  • Veranstaltungen: Bauphysik 6/2016
    • Pages: 412 - 412
      PubDate: 2016-12-01T05:22:20.799609-05:
      DOI: 10.1002/bapi.201690054
       
 
 
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