Energy Storing and Positional Tendon Fascicles Exhibit Different Fatigue Behaviour

2013 ◽  
Author(s):  
J. H. Shepherd ◽  
K. Legerlotz ◽  
T. Demirci ◽  
C. Klemt ◽  
G. P. Riley ◽  
...  
Keyword(s):  
Fatigue Failure ◽  
Potential Benefit ◽  
Fatigue Behaviour ◽  
Repeated Loading

Overuse tendinopathies are often considered to be the result of repeated microstrain below the failure threshold, analogous to the fatigue failure of materials under repeated loading [1, 2]. Investigation of tendon overuse in vitro is thus of potential benefit towards characterizing the progression of damage.

scholarly journals Differential Effects of Antiseptic Mouth Rinses on SARS-CoV-2 Infectivity In Vitro

Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 272
Author(s):  
Chuan Xu ◽  
Annie Wang ◽  
Eileen R. Hoskin ◽  
Carla Cugini ◽  
Kenneth Markowitz ◽  
...  
Keyword(s):  
Potential Benefit ◽  
Povidone Iodine ◽  
Cellular Damage ◽  
Virus Infectivity ◽  
Viral Infectivity ◽  
Mouth Rinse ◽  
Prolonged Incubation ◽  
Differential Effects ◽  
Mouth Rinses

Severe acute respiratory syndrome-related coronavirus (SARS-CoV-2) is detectable in saliva from asymptomatic individuals, suggesting a potential benefit from the use of mouth rinses to suppress viral load and reduce virus spread. Published studies on the reduction of SARS-CoV-2-induced cytotoxic effects by mouth rinses do not exclude antiseptic mouth rinse-associated cytotoxicity. Here, we determined the effect of commercially available mouth rinses and antiseptic povidone-iodine on the infectivity of replication-competent SARS-CoV-2 viruses and of pseudotyped SARS-CoV-2 viruses. We first determined the effect of mouth rinses on cell viability to ensure that antiviral activity was not a consequence of mouth rinse-induced cytotoxicity. Colgate Peroxyl (hydrogen peroxide) exhibited the most cytotoxicity, followed by povidone-iodine, chlorhexidine gluconate (CHG), and Listerine (essential oils and alcohol). The potent antiviral activities of Colgate Peroxyl mouth rinse and povidone-iodine were the consequence of rinse-mediated cellular damage when the products were present during infection. The potency of CHG was greater when the product was not washed off after virus attachment, suggesting that the prolonged effect of mouth rinses on cells impacts the antiviral outcome. To minimalize mouth rinse-associated cytotoxicity, mouth rinse was largely removed from treated viruses by centrifugation prior to infection of cells. A 5% (v/v) dilution of Colgate Peroxyl or povidone-iodine completely blocked viral infectivity. A similar 5% (v/v) dilution of Listerine or CHG had a moderate suppressive effect on the virus, but a 50% (v/v) dilution of Listerine or CHG blocked viral infectivity completely. Mouth rinses inactivated the virus without prolonged incubation. The new infectivity assay, with limited impacts of mouth rinse-associated cytotoxicity, showed the differential effects of mouth rinses on SARS-CoV-2 infection. Our results indicate that mouth rinses can significantly reduce virus infectivity, suggesting a potential benefit for reducing SARS-CoV-2 spread.

Fatigue behaviour of Vossloh SKL14 tension clamps

2021 ◽  
Author(s):  
Bohumil Culek ◽  
Eva Schmidová ◽  
Petr Tomek ◽  
Petr Vnenk ◽  
Marek Pětioký
Keyword(s):  
Service Life ◽  
Fatigue Failure ◽  
Critical Points ◽  
Fatigue Curve ◽  
Fatigue Behaviour ◽  
Fractographic Analysis ◽  
Railway Track ◽  
Strain Gauges ◽  
Dynamically Loaded ◽  
Fatigue Failures

<p>The reliability of the railway superstructure depends, among other things, on the actual fastening of the rail to the sleepers. This structure is extremely dynamically loaded. In the paper, the attention is paid to the flexible Vossloh W14 fastening system with the use of SKL14 tension clamps. These clamps are often damaged by fatigue failures, especially in curves of small radii (R &lt; 400 m). Within the research, fracture areas were identified and a fractographic analysis was performed. The analysis proved fatigue failure and, therefore, an estimation of the service life of the clamps was made. The evaluation was focused on a selected area of railway track where the fatigue-damaged clamps were found. The strain gauges were placed directly on the clamps at critical points and the obtained values were confronted with the experimentally obtained fatigue curve. Based on the presented findings, the service life of the clamps in the selected track was identified.</p>

Fatigue Failure Modes in Self-Piercing Riveted Aluminium Alloy Joints

Volume 3 ◽  
2004 ◽  
Author(s):  
L. Han ◽  
K. Young ◽  
R. Hewitt ◽  
A. Chrysanthou ◽  
J. M. O’Sullivan
Keyword(s):  
Aluminium Alloy ◽  
Fatigue Failure ◽  
Failure Modes ◽  
Surface Condition ◽  
Fatigue Behaviour ◽  
Alloy Sheet ◽  
Static Tests ◽  
Failure Patterns ◽  
Interfacial Conditions ◽  
Sheet Surface

Self-piercing riveting, as an alternative joining method to spot-welding, has attracted considerable interest from the automotive industry and has been widely used in aluminium intensive vehicles. One of the important factors that need to be considered is the effect of cyclic loading in service, leading to possible fatigue failure. The previous work reported in the public domain on the behaviour of self-piercing rivets has mainly focused on static tests. The work which is reported in this paper is concerned with the fatigue behaviour of single-rivet joints, joining two 2mm 5754 aluminium alloy sheets. The investigation also examined the effect of interfacial conditions on the fatigue behaviour. A number of fatigue failure mechanisms were observed based on rivet fracture, sheet fracture and combinations of these. The investigation has shown that they were dependent on the applied load and the sheet surface condition. Three-parameter Weibull analysis, using Reliasoft Weibull ++5.0 software, was conducted to analyse the experimental results. The analysis enabled the prediction of early-type failure (infant mortality failure) and wear-out failure patterns depending on the condition of the self-piercing riveted joints and the alloy sheet surface.

Failure of Locally Buckled Pipelines

2006 ◽  
Author(s):  
E. Dama ◽  
S. A. Karamanos ◽  
A. M. Gresnigt
Keyword(s):  
Finite Element ◽  
Internal Pressure ◽  
Fatigue Failure ◽  
Structural Integrity ◽  
Mechanical Damage ◽  
Strain Range ◽  
Structural Condition ◽  
Repeated Loading ◽  
Maximum Strain ◽  
Pipe Burst

Mechanical damage in steel pipelines in the form of local buckles due to excessive bending deformation, may severely threaten their structural integrity. The present paper describes experimental and numerical research conducted to assess the structural condition of buckled pipes, subjected to both bending and internal pressure. Fatigue failure under repeated loading is mainly investigated, whereas pipe burst due to internal pressure is also examined. Three full-scale buckled pipe specimens are tested under pressure and bending loads to determine their structural capacity. In addition, using nonlinear finite element tools, an extensive parametric study is conducted, to determine the critical locations at the buckled area, at which maximum strain variation occurs, as well as to investigate the influence of several geometrical and mechanical parameters. Using the maximum strain range from the finite element computations, and a simple S-N approach, reasonable predictions are obtained for the number of cycles to failure observed in the tests. The results of the present study demonstrate that under repeated loading, fatigue failure occurs in the buckled area at the location of maximum strain range. It is also found that the burst pressure may not be affected by the presence of buckles.

scholarly journals Improved Muscle Function After Injury with the Application of a Biological Decellularized Matrix

2020 ◽  
Author(s):  
Amina El Ayadi ◽  
Melody R.S. Threlkeld ◽  
Steven E. Wolf ◽  
Juquan Song
Keyword(s):  
Cell Proliferation ◽  
Muscle Cell ◽  
Muscle Function ◽  
Potential Benefit ◽  
Time Course ◽  
Isometric Force ◽  
Cell Proliferation And Differentiation ◽  
Function Recovery ◽  
Proliferation And Differentiation

Abstract Background: Skeletal muscle injury leads to loss of muscle function that lasts well into recovery and can be permanent. Application of the novel bio-scaffold termed porcine-derived urinary bladder matrix (UBM) has a potential benefit to mitigate injury through tissue regeneration. To date, findings of potential benefit in animal models were limited to short assessment times. The purpose of this study was to investigate whether UBM treatment 14 days after injury sustainably improves the recovery of muscle function in injured mice. Methods: C57BL/6 adult male mice received bilateral laceration injuries on the gastrocnemius (GN) muscle under anesthesia and were then treated with vehicle or 150 µg of UBM nanoparticles. Treatment was applied immediately after injury or 14 days later. Muscle isometric force was measured 60 days after injury. Previous time course analyses have shown that muscle function did not start to improve until after 42 days after injury. Therefore, we designed a second experiment to trace the time course of UBM effects on muscle function recovery by measuring the isometric muscle force at 49 and 90 days after injury. In vitro, we analyzed the effects of UBM on muscle cell proliferation and differentiation. Results: UBM promotes muscle cell proliferation and differentiation. Twitch (Pt), tetanic (Po) force and maximal fatigue were significantly decreased in the injured mice on day 60. Muscle fatigue maximum force significantly recovered when UBM treatment was applied 14 days after injury (p<0.05) but not when UBM was applied immediately after the injury. Time course analysis demonstrated that UBM improvement of Pt and Po was evident by day 49 after injury (p<0.05). However, no further muscle function improvement was observed on day 90. Conclusions: Delayed treatment with the UBM improves muscle function recovery following laceration injury starting 49 days after injury. These effects may be mediated by improvements in muscle cell proliferation and differentiation. This animal model is suitable to test other therapeutic strategies to improve muscle function after injury.

scholarly journals Formulation and optimization of water soluble granules of Withania Somnifera

2021 ◽  
Vol 11 (6) ◽  
pp. 26-30
Author(s):  
Dilip Kumar Tiwari ◽  
Kaushelendra Mishra ◽  
Neelima Mishra ◽  
Neeraj Upmanyu
Keyword(s):  
Drug Release ◽  
Potential Benefit ◽  
Withania Somnifera ◽  
Research Work ◽  
Herbal Medicines ◽  
Water Extract ◽  
Water Soluble ◽  
Nootropic Activity ◽  
In Vitro Drug Release

Herbal medicines have great demand in the treatment of various kinds of illness.  Ayurvedic system of medicine has consisted of many herbal sources in which ashwagandha one of them which are the very popular herbal sources. Many literature surveys suggest that ashwagandha is used as an immunomodulator, tranquilizer, antioxidant, antidiabetic, and nootropic activity. Present research work explored the potential benefit of ashwagandha by designing suitable granules of its water extract. Further, it is characterized by various parameters and In-vitro drug release Keywords: Immunomodulator, Tranquilizers Ayurvedic, Ashwagandha, Granules

Topographical modulation of macrophage phenotype by shrink-film multi-scale wrinkles

2016 ◽  
Vol 4 (6) ◽  
pp. 948-952 ◽  
Author(s):  
Tingting Wang ◽  
Thuy U. Luu ◽  
Aaron Chen ◽  
Michelle Khine ◽  
Wendy F. Liu
Keyword(s):  
Cell Shape ◽  
Host Response ◽  
Potential Benefit ◽  
Macrophage Phenotype ◽  
Macrophage Cell ◽  
Multi Scale ◽  
Material Surfaces ◽  
Tissue Healing

Biomimetic multi-scale wrinkles alters macrophage cell shape and promotes antiinflammatory activation in vitro, and modulates the host response in vivo, suggesting a potential benefit for wrinkled material surfaces to promote tissue healing and remodeling.

scholarly journals Efficacy of Antifungal Monotherapies and Combinations againstAspergillus calidoustus

2018 ◽  
Vol 62 (12) ◽  
Author(s):  
E. Glampedakis ◽  
A. T. Coste ◽  
M. Aruanno ◽  
D. Bachmann ◽  
E. Delarze ◽  
...  
Keyword(s):  
Synergistic Effect ◽  
Therapeutic Range ◽  
Potential Benefit ◽  
Galleria Mellonella ◽  
Fungal Infections ◽  
Antifungal Drugs ◽  
Content Type ◽  
Content Model ◽  
Poor Outcomes

ABSTRACTInvasive fungal infections due toAspergillus calidoustuswith decreased azole susceptibility are emerging in the setting of azole prophylaxis and are associated with poor outcomes. We assessed thein vitroactivity of antifungal drugs used alone or in combinations againstA. calidoustusand found a synergistic effect between voriconazole and terbinafine at concentrations within the therapeutic range. An invertebrateGalleria mellonellamodel ofA. calidoustusinfection tended to support the potential benefit of this combination.

scholarly journals Shoulder Risk Assessment Based on Fatigue Failure Theory

2019 ◽  
Vol 63 (1) ◽  
pp. 1117-1121
Author(s):  
Dania Bani Hani ◽  
Sean Gallagher ◽  
Richard F. Sesek ◽  
Rong Huangfu ◽  
Mark C. Schall ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Fatigue Failure ◽  
Animal Studies ◽  
Failure Process ◽  
Epidemiological Studies ◽  
Cumulative Damage ◽  
Assessment Model ◽  
Failure Theory ◽  
Epidemiological Database

Recent studies support the notion that a fatigue failure process may be responsible for the development of MSDs, including epidemiological studies, animal studies, and in vitro testing of musculoskeletal tissues. This study presents a new risk assessment model for the shoulder, which estimates the daily dose of the cumulative damage (CD) for the shoulder and allows the CD for multiple tasks to be summed to get an overall estimate for the daily cumulative damage. Videotapes of jobs from an existing epidemiological study from a large U.S. automotive manufacturer were analyzed to get exposure information required for the model. The model was then validated using outcomes from the epidemiological database. Logistic regression was used to assess the associations between Log CD and various shoulder outcomes. Results indicated that the cumulative damage for the shoulder was highly associated with all shoulder outcomes and that application of the fatigue failure methods also works extremely well in assessing the probability of association with shoulder outcomes. These results provide further support regarding the role of the fatigue failure process in the development of MSDs.

Sign in / Sign up

Export Citation Format

Share Document