Measurement of Mechanical Factors of Running Efficiency

Author(s):  
Alain Belli
Keyword(s):  
1996 ◽  
Vol 6 (11) ◽  
pp. 1555-1566 ◽  
Author(s):  
Olivier Thoumine

2014 ◽  
Vol 1 (2) ◽  
pp. 20-23
Author(s):  
O. Ivashchenko ◽  
O. Ivashchenko

Aim. Studying of black nightshade young plants’ response to the induced mechanical stresses. Methods. Researches conducted in small plot fi eld experiments. Results. Change of sensitivity level of Solanum nigrum L. plants depending on phases of their development at the moment of damage of elevated parts has been proven. Owing to loss of the surface capable to photosynthesis, there is an essential decrease in volumes of photosynthesis at plants of weed survived and their possibilities of ontogeny passage. The deep induced dis- stresses reduce biological effi ciency of plants, their ability to accumulate weight and to form seeds and even lead them to death. Conclusions. The defi ned principles of response of weed plants to the induced mechanical dis-stresses are can be used for working out and ecological receptions of crops protection from weeds.


2021 ◽  
pp. 194589242198916
Author(s):  
Henry D. Zheng ◽  
Jeffrey C. Mecham ◽  
Yassmeen Abdel-Aty ◽  
Devyani Lal ◽  
Michael J. Marino

Background The histopathology and microbiology associated with silent sinus syndrome (SSS) have not been well described. Objective This study details the histopathological and microbiological characteristics in addition to radiographic findings of SSS in comparison to those of chronic maxillary sinusitis (CRS). Methods 42 patients diagnosed with SSS at Mayo Clinic Hospital in Arizona were identified. Paranasal computed tomography scans of the 42 SSS patients as well as 42 matched CRS patients were analyzed in order to assess differences in the prevalence of septal spurs/deviation. 20 of the SSS patients and 19 of the matched CRS patients also had histopathology and microbiology reports, which were compiled and summarized. Additionally, 19 SSS and 19 matched CRS patients were contacted via phone survey for a more complete patient history regarding maxillary dental disease/surgery. Results SSS patients have a significantly higher prevalence of septal spurs/deviation than CRS patients. The microbiomes of SSS patients more closely resemble those of healthy controls than those of CRS patients. Analysis of the histopathology of SSS reveals chronic, non-specific inflammation similar to that seen in non-eosinophilic CRS without polyps. SSS patients were significantly more likely to have a history of maxillary dental disease requiring surgery. Conclusion These data support the hypothesis that the pathogenesis of SSS is more likely due to anatomical/mechanical factors than inflammatory/microbiological factors.


2021 ◽  
Vol 7 ◽  
pp. 205951312098032
Author(s):  
Chenyu Huang ◽  
Rei Ogawa

Introduction: Keloids are pathological scars that are notorious for their chronic and relentless invasion into adjacent healthy skin, with commonly seen post-therapeutic recurrence after monotherapies. Methods: An English literature review on keloid pathophysiology was performed by searching the PubMed, Embase and Web of Science databases, to find out the up-to-date relevant articles. The level of evidence was evaluated based on the included studies with the highest level of evidence first. Results: Keloid morphology, signs, symptoms and the histopathological changes that occur in the local cells and extracellular matrix components are described. The theories on the pathophysiology of keloidogenesis that have been proposed to date are also covered; these include endocrinological, nutritional, vascular, and autoimmunological factors. In addition, we describe the local mechanical forces (and the mechanosignalling pathways by which these forces shape keloid cell activities) that promote keloid formation and determine the direction of invasion of keloids and the body sites that are prone to them. Conclusion: A better understanding of this pathological entity, particularly its mechanobiology, will aid the development of new diagnostic and therapeutic strategies for use in the clinic to prevent, reduce or even reverse the growth of this pathological scar. Lay Summary Keloids are skin scars that are famous for their chronic invasion into healthy skin, with commonly seen recurrence after surgeries. Cells such as lymphocytes, macrophages, mast cells and endothelial cells are involved in keloid growth. Particularly, endocrinological, nutritional, vascular, autoimmunological and mechanical factors actively take part in keloid progression.


2021 ◽  
Vol 190 ◽  
pp. 107534
Author(s):  
Zhengtong Li ◽  
Tingzhen Ming ◽  
Shurong Liu ◽  
Chong Peng ◽  
Renaud de Richter ◽  
...  

2019 ◽  
Vol 8 (12) ◽  
pp. 2091 ◽  
Author(s):  
Stuart B. Goodman ◽  
Jiri Gallo

Clinical studies, as well as in vitro and in vivo experiments have demonstrated that byproducts from joint replacements induce an inflammatory reaction that can result in periprosthetic osteolysis (PPOL) and aseptic loosening (AL). Particle-stimulated macrophages and other cells release cytokines, chemokines, and other pro-inflammatory substances that perpetuate chronic inflammation, induce osteoclastic bone resorption and suppress bone formation. Differentiation, maturation, activation, and survival of osteoclasts at the bone–implant interface are under the control of the receptor activator of nuclear factor kappa-Β ligand (RANKL)-dependent pathways, and the transcription factors like nuclear factor κB (NF-κB) and activator protein-1 (AP-1). Mechanical factors such as prosthetic micromotion and oscillations in fluid pressures also contribute to PPOL. The treatment for progressive PPOL is only surgical. In order to mitigate ongoing loss of host bone, a number of non-operative approaches have been proposed. However, except for the use of bisphosphonates in selected cases, none are evidence based. To date, the most successful and effective approach to preventing PPOL is usage of wear-resistant bearing couples in combination with advanced implant designs, reducing the load of metallic and polymer particles. These innovations have significantly decreased the revision rate due to AL and PPOL in the last decade.


2013 ◽  
Vol 39 (1) ◽  
pp. 20-29 ◽  
Author(s):  
R. Savage

This review article examines the mechanical factors involved in tendon repair by sutures. The repair strength, repair stiffness and gap resistance can be increased by increasing the number of core strands and anchor points, by increased anchor point efficiency and the use of peripheral sutures, and by using thicker sutures. In the future, laboratory tests could be standardized to a specific animal model and to a defined cyclic motion programme. Clinical studies support the use of multi-strand core and peripheral sutures, but two-strand core sutures are not adequate to ensure consistently good clinical results. Training surgeons in complex tendon repair techniques is essential.


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