Contractile Properties of Vaginal Tissue

2020 ◽  
Vol 142 (8) ◽  
Author(s):  
Alyssa Huntington ◽  
Kandace Donaldson ◽  
Raffaella De Vita
Keyword(s):  
Mechanical Properties ◽  
Pelvic Floor ◽  
Surgical Mesh ◽  
Pelvic Floor Disorders ◽  
Negative Impact ◽  
Experimental Studies ◽  
Future Research ◽  
Neural Pathways ◽  
Vaginal Tissue ◽  
Experimental Findings

Abstract The vagina is an important organ of the female reproductive system that has been largely understudied in the field of biomechanics. In recent years, some research has been conducted to evaluate the mechanical properties of the vagina, but much has focused on characterizing the passive mechanical properties. Because vaginal contractions play a central role in sexual function, childbirth, and development and treatment of pelvic floor disorders, the active mechanical properties of the vagina must be also quantified. This review surveys and summarizes published experimental studies on the active properties of the vagina including the differences in such properties determined by anatomic regions and orientations, neural pathways, life events such as pregnancy and menopause, pelvic floor disorders such as prolapse, and surgical mesh treatment. Conflicting experimental findings are presented, illustrating the need for further research on the active properties of the vagina. However, consensus currently exists regarding the negative impact of surgical mesh on vaginal contractility. This review also identifies knowledge gaps and future research opportunities, thus proving a firm foundation for novice and experienced researchers in this emerging area of biomechanics and encouraging more activity on women's sexual and reproductive health research.

Research Progress on Mechanical Properties of Short Carbon Fibre/Epoxy Composites

2019 ◽  
Vol 12 (1) ◽  
pp. 3-13 ◽  
Author(s):  
Guanghui Zhao ◽  
Jijia Zhong ◽  
Y.X. Zhang
Keyword(s):  
Mechanical Properties ◽  
Carbon Fibre ◽  
Mechanical Performance ◽  
Experimental Studies ◽  
Weight Ratio ◽  
Epoxy Composites ◽  
Experimental Techniques ◽  
Research Progress ◽  
Future Research ◽  
Short Carbon

Background: Short carbon fibre reinforced epoxy composites have many advantages such as high strength-to-weight ratio, corrosion resistance, low cost, short fabrication time and easy manufacturing. Researches on the mechanical performance of the composites are mainly carried out by means of experimental techniques and numerical calculation. Objective: The study aims to report the latest progress in the studies of mechanical properties of short carbon fibre reinforced epoxy composites. Methods: Based on recently published patents and journal papers, the experimental studies of short carbon fibre reinforced epoxy composites are reviewed and the effects of short carbon fibre on the mechanical properties of the composites are discussed. Numerical studies using representative volume element in simulating macroscopic mechanical properties of the short fibre reinforced composites are also reviewed. Finally, future research of short carbon fibre reinforced epoxy composites is proposed. Results: Experimental techniques, experimental results and numerical simulating methods are discussed. Conclusion: Mechanical properties of epoxy can be improved by adding short carbon fibres. Fiber surface treatment and matrix modification are effective in enhancing interfacial adhesion between fiber and matrix, and as a result, better mechanical performance is achieved. Compared to the studies on equivalent mechanical properties of the composites, researches on the micro-mechanism of interaction between fiber and matrix are still in infancy due to the complexity of both the internal structure and reinforcing mechanism.

scholarly journals Experimental Research on the Mechanical Properties of Tailing Microcrystalline Foam Glass

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2048 ◽  
Author(s):  
Jinliang Bian ◽  
Wanlin Cao ◽  
Lin Yang ◽  
Cunqiang Xiong
Keyword(s):  
Mechanical Properties ◽  
Modulus Of Elasticity ◽  
Foam Glass ◽  
Experimental Studies ◽  
Great Influence ◽  
Future Research ◽  
Stress And Strain ◽  
Light Weight ◽  
Foaming Agent ◽  
Strength Tests

Tailing microcrystalline foam glass (TMFG) is a building material that not only has the characteristics of light weight, fire resistance, and thermal insulation, but also has decorative applications. TMFG has a broad application prospect, but there has been little research on the macroscale mechanical properties of this material. In order to analyze TMFG basic mechanical properties, a series of experimental studies were carried out by performing the four-point flexural, shear, uniaxial compression, and splitting tensile strength tests. The research showed that the foaming agent (SiC) had a great influence on the mechanical properties of the material. With the reduction of the amount of SiC, the strength of the material and brittle failure increased. The microcrystalline decoration surface improved the flexural strength and compression strength of the tailing microcrystalline foam glass. The modulus of elasticity and the Poisson’s ratio are discussed, and a formula for the modulus of elasticity is proposed. Based on the analysis of the stress and strain curves, a constitutive model is proposed for the application of tailing microcrystalline foam glass and future research on this material.

Understanding krill growth and aging: the contribution of experimental studies

2000 ◽  
Vol 57 (S3) ◽  
pp. 168-177 ◽  
Author(s):  
Stephen Nicol
Keyword(s):  
Population Biology ◽  
Experimental Studies ◽  
Euphausia Superba ◽  
Future Research ◽  
Ecological Studies ◽  
Experimental Approaches ◽  
Increasing Knowledge ◽  
Growth And Aging ◽  
Experimental Findings

Krill have been viewed as difficult animals to examine experimentally. Consequently, most information on growth and age of these pelagic crustaceans has come from demographic studies on preserved specimens. Only one species of krill, Euphausia superba, has been intensively studied in the laboratory, but the experimental findings on growth and age from these studies have fundamentally altered our perceptions of the population biology of this species. Most other species of krill remain in the preexperimental phase of understanding; thus, there remain considerable uncertainties regarding their growth and longevity. Unfortunately, these uncertainties are often ignored in ecological studies. In this paper, I have examined the role that experimental studies have played in increasing knowledge of the population biology of krill, particularly in the fields of growth and aging. I have indicated where discrepancies exist between field-based and experimental approaches and I outline some approaches for exploring these discrepancies and suggest some potentially fruitful areas for future research.

Pelvic Floor Disorders Linked to Low Vitamin D

2011 ◽  
Vol 41 (19) ◽  
pp. 36
Author(s):  
AMY ROTHMAN SCHONFELD
Keyword(s):  
Vitamin D ◽  
Pelvic Floor ◽  
Pelvic Floor Disorders

Applying personalized medicine to adult severe asthma

2021 ◽  
Vol 42 (1) ◽  
pp. e8-e16 ◽  
Author(s):  
Angelica Tiotiu
Keyword(s):  
Personalized Medicine ◽  
Severe Asthma ◽  
Negative Impact ◽  
Target Therapy ◽  
Asthma Management ◽  
Future Research ◽  
Biologic Therapies ◽  
Eosinophilic Asthma ◽  
Definition Of ◽  
Structured Approach

Background: Severe asthma is a heterogeneous disease that consists of various phenotypes driven by different pathways. Associated with significant morbidity, an important negative impact on the quality of life of patients, and increased health care costs, severe asthma represents a challenge for the clinician. With the introduction of various antibodies that target type 2 inflammation (T2) pathways, severe asthma therapy is gradually moving to a personalized medicine approach. Objective: The purpose of this review was to emphasize the important role of personalized medicine in adult severe asthma management. Methods: An extensive research was conducted in medical literature data bases by applying terms such as “severe asthma” associated with “structured approach,” “comorbidities,” “biomarkers,” “phenotypes/endotypes,” and “biologic therapies.” Results: The management of severe asthma starts with a structured approach to confirm the diagnosis, assess the adherence to medications and identify confounding factors and comorbidities. The definition of phenotypes or endotypes (phenotypes defined by mechanisms and identified through biomarkers) is an important step toward the use of personalized medicine in asthma. Severe allergic and nonallergic eosinophilic asthma are two defined T2 phenotypes for which there are efficacious targeted biologic therapies currently available. Non-T2 phenotype remains to be characterized, and less efficient target therapy exists. Conclusion: Despite important progress in applying personalized medicine to severe asthma, especially in T2 inflammatory phenotypes, future research is needed to find valid biomarkers predictive for the response to available biologic therapies to develop more effective therapies in non-T2 phenotype.

Employees' Perceptions of the Effects of Retrenchment on Job Stress and Organisational Commitment in a Mining Company

2019 ◽  
Vol 43 ◽  
Author(s):  
Landiswa Seteni ◽  
Pierre Joubert ◽  
Manilall Dhurup
Keyword(s):  
Job Stress ◽  
Quantitative Research ◽  
Negative Impact ◽  
Surface Mining ◽  
Future Research ◽  
Global Changes ◽  
Organisational Commitment ◽  
Consultation Process ◽  
Mining Company ◽  
Time Stress

Over the past decade, South African organisations have had to cope with an ever-increasing rate of local and global changes. There have been considerable and ongoing socio-political changes, resulting from new government regulations. Most organisations have experienced some type of downturn, whether due to external business factors or poor internal performance. A typical response to organisational decline is retrenchment. Our study sought to explore employees’ perceptions of the effects of retrenchment on job stress and organisational commitment in a mining company. The study was located within a quantitative research paradigm. Four research hypotheses were posited and data was collected in one region from a sample of 400 surface mining employees, including management, administrators, engineers and artisans. The results showed that the effects of retrenchment did not have a negative impact on job stress (time stress and anxiety). This may be due to the fact that the mining company in question had a planning and consultation process in place for the employees prior to the retrenchment process. The results also showed that job stress (time stress and anxiety) was negatively associated with organisational commitment. To conclude this article we discuss the implications of our findings, outline the limitations of our study and make recommendations for future research.

Methodology of studying the mechanical properties of composite materials (reinforced concrete)

2018 ◽  
Vol 84 (12) ◽  
pp. 61-67
Author(s):  
V. A. Eryshev
Keyword(s):  
Mechanical Properties ◽  
Reinforced Concrete ◽  
Experimental Studies ◽  
Analytical Relationship ◽  
Hardened Concrete ◽  
Deformation Model ◽  
Joint Work ◽  
Concrete Shrinkage ◽  
Axial Tension ◽  
Tension And Compression

The mechanical properties of a complex composite material formed by steel and hardened concrete, are studied. A technique of operative quality control of new credible concrete and reinforcement, both in laboratory and field conditions is developed for determination of the strength and strain characteristics of materials, as well as cohesion forces determining their joint operation under load. The design of the mobile unit is presented. The unit provides a possibility of changing the direction of loading and testing the reinforced element of the given shape both for tension and compression. Moreover, the nomenclature of testing equipment and the number of molds for manufacturing concrete samples substantially decrease. Using the values of forcing resulting in concrete cracking when the joint work of concrete and reinforcement is disrupted the values of the inherent stresses and strains attributed to the concrete shrinkage are determined. An analytical relationship between the forces and deformations of the reinforced concrete sample with central reinforcement is derived for axial tension and compression, with allowance for strains and stresses in the reinforcement and concrete resulted from concrete shrinkage. The results of experimental studies are presented, including tension diagrams and diagrams of developing axial deformations with an increase in the load under the central loading of the reinforced elements. A methodology of accounting for stresses and deformations resulted from concrete shrinkage is developed. The applicability of the derived analytical relationships between stresses and deformations on the material diagrams to calculations of the reinforced concrete structures in the framework of the deformation model is estimated.

RECLAMATION AND CULVERT CROSSINGS MADE OF CORRUGATED PIPES ON SPAWNING STREAMS

2020 ◽  
pp. 68-77
Author(s):  
O.N. CHERNYKH ◽  
◽  
A.V. RBURLACHENKO
Keyword(s):  
Single Point ◽  
Experimental Studies ◽  
Fish Passage ◽  
Future Research ◽  
Fish Stocks ◽  
Metal Structures ◽  
Natural Reproduction ◽  
Spiral Shape ◽  
Corrugated Metal ◽  
Spawning Streams

Recommendations are presented for solving issues that arise in the design and operation of tubular transport crossings of corrugated metal structures through spawning streams while ensuring the safety and natural reproduction of fish stocks. There are discussed the results of experimental studies of culverts made of metal corrugated pipes with a normal and spiral shape of corrugation the bottom of which is buried and filled with suitable granular material to the level of the natural channel of a small watercourse. It is established that when 10% of the area of the corrugated pipe is occupied by stone filling, its throughput is reduced by about 10-12%. Based on the review of the existing literature and the results of laboratory experiments, data is provided to estimate the values of the roughness coefficients of the composite cross-section of a single-point junction and directions for future research on culvert reclamation are outlined. Studying of the structure of the velocity distribution in culverts can lead to the improved conditions for fish passage without installing special structural elements in the transit path of the fish passage structure.

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