The influence of resistance exercise training prescription variables on skeletal muscle mass,strength,and physical function in healthy adults:An umbrella review

Purpose:The aim of this umbrella review was to determine the impact of resistance training(RT)and individual RT prescription variables on muscle mass,strength,and physical function in healthy adults.Methods:Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines,we systematically searched and screened eligible systematic reviews reporting the effects of differing RT prescription variables on muscle mass(or its proxies),strength,and/or physical function in healthy adults aged>18 years.Results:We identified 44 systematic reviews that met our inclusion criteria.The methodological quality of these reviews was assessed using A Measurement Tool to Assess Systematic Reviews;standardized effectiveness statements were generated.We found that RT was consistently a potent stimulus for increasing skeletal muscle mass(4/4 reviews provide some or sufficient evidence),strength(4/6 reviews provided some or sufficient evidence),and physical function(1/1 review provided some evidence).RT load(6/8 reviews provided some or sufficient evidence),weekly frequency(2/4 reviews provided some or sufficient evidence),volume(3/7 reviews provided some or sufficient evidence),and exercise order(1/1 review provided some evidence)impacted RT-induced increases in muscular strength.We discovered that 2/3 reviews provided some or sufficient evidence that RT volume and contraction velocity influenced skeletal muscle mass,while 4/7 reviews provided insufficient evidence in favor of RT load impacting skeletal muscle mass.There was insufficient evidence to conclude that time of day,periodization,inter-set rest,set configuration,set end point,contraction velocity/time under tension,or exercise order(only pertaining to hypertrophy)influenced skeletal muscle adaptations.A paucity of data limited insights into the impact of RT prescription variables on physical function.Conclusion:Overall,RT increased muscle mass,strength,and physical function compared to no exercise.RT intensity(load)and weekly frequency impacted RT-induced increases in muscular strength but not muscle hypertrophy.RT volume(number of sets)influenced muscular strength and hypertrophy.

The Impact of the Inclusion of MgO Nano-Fillers in a Polyethylene Matrix on Dielectric Strength and Resistance to Partial Discharges

One commonly used strategy to enhance polymers specific properties such as the resistance to partial discharges erosion is the incorporation into the polymeric matrix of inorganic micro or nanoparticles. This study focused on the dielectric properties of Low-Density Polyethylene (LDPE) filled with nano-sized Magnesium Oxide (MgO) particles compounded by thermo-mechanical process and one of the purposes was to establish appropriate processing parameters in order to reach the desired dielectric properties. LDPE was used as a matrix and was reinforced by MgO particles having a nominal average size of 30 nm. The MgO nanoparticles were treated with a silane coupling agent (3-Glycidyloxypropyl Trimethoxysilane). The samples were initially prepared in a melt-mixing chamber with a MgO content of 1% wt. These pre-mixed samples were further treated by the means of thermo-mechanical mixing in a conical co-rotating twin-screw extruder in order to improve the dispersion and distribution of the MgO particles. In this report, both lifetime under a PD activity and AC dielectric strength of pure and nano-filled LDPE samples have been measured and compared. Nano-filled LDPE samples were found to exhibit an improve lifetime, without any detrimental impact on their short-term dielectric strength. This suggests that nano-filled LDPE may be for electric applications for which the dielectric materials may be exposed to partial discharge activities. This is significant result for the use of MgO-reinforced PE as an insulating material for HV cables since the resistance to PD is closely related to treeing resistance which is the main electrical degradation mechanism that leads to failure for shielded extruded power cables.

Muscle strength and non-alcoholic fatty liver disease/metabolicassociated fatty liver disease

This editorial comments on an article published in a recent issue of World Journal of Gastroenterology,entitled“Association of low muscle strength with metabolic dysfunction-associated fatty liver disease:A nationwide study”.We focused on the association between muscle strength and the incidence of non-alcoholic fatty liver disease(NAFLD)and metabolic-associated fatty liver disease(MAFLD),as well as the mechanisms underlying the correlation and related clinical applications.NAFLD,which is now redefined as MAFLD,is one of the most common chronic liver diseases globally with an increasing prevalence and is characterized by malnutrition,which may contribute to decreased muscle strength.Reduction of muscle strength reportedly has a pathogenesis similar to that of NAFLD/MAFLD,including insulin resistance,inflammation,sedentary behavior,as well as insufficient vitamin D.Multiple studies have focused on the relationship between sarcopenia or muscle strength and NAFLD.However,studies investigating the relationship between muscle strength and MAFLD are limited.Owing to the shortage of specific medications for NAFLD/MAFLD treatment,early detection is essential.Furthermore,the relationship between muscle strength and NAFLD/MAFLD suggests that improvements in muscle strength may have an impact on disease prevention and may provide novel insights into treatments including dietary therapy,as well as tailored physical activity.

Determining the Onset and Strength of Unforced Wave Breaking in A Numerical Wave Tank

A numerical wave tank is used to investigate the onset and strength of unforced wave breaking, and the waves have three types of initial spectra： constant amplitude spectrum, constant steepness spectrum and Pierson-Moscowitz spectrum. Numerical tests are performed to validate the model results. Then, the onset of wave breaking is discussed with geometric, kinematic, and dynamic breaking criteria. The strength of wave breaking, which is always characterized by the fractional energy loss and breaking strength coefficient, is studied for different spectra. The results show how the energy growth rate is better than the initial wave steepness on estimating the fractional energy losses as well as breaking strength coefficient.

Exploring an eco-friendly approach to improve soil tensile behavior and cracking resistance

Soil tensile strength is a critical parameter governing the initiation and propagation of tensile cracking.This study proposes an eco-friendly approach to improve the tensile behavior and crack resistance of clayey soils.To validate the feasibility and efficacy of the proposed approach,direct tensile tests were employed to determine the tensile strength of the compacted soil with different W-OH treatment concentrations and water contents.Desiccation tests were also performed to evaluate the effectiveness of W-OH treatment in enhancing soil tensile cracking resistance.During this period,the effects of W-OH treatment concentration and water content on tensile properties,soil suction and microstructure were investigated.The tensile tests reveal that W-OH treatment has a significant impact on the tensile strength and failure mode of the soil,which not only effectively enhances the tensile strength and failure displacement,but also changes the brittle failure behavior into a more ductile quasi-brittle failure behavior.The suction measurements and mercury intrusion porosimetry(MIP)tests show that W-OH treatment can slightly reduce soil suction by affecting skeleton structure and increasing macropores.Combined with the microstructural analysis,it becomes evident that the significant improvement in soil tensile behavior through W-OH treatment is mainly attributed to the W-OH gel's ability to provide additional binding force for bridging and encapsulating the soil particles.Moreover,desiccation tests demonstrate that W-OH treatment can significantly reduce or even inhibit the formation of soil tensile cracking.With the increase of W-OH treatment concentration,the surface crack ratio and total crack length are significantly reduced.This study enhances a fundamental understanding of eco-polymer impacts on soil mechanical properties and provides valuable insight into their potential application for improving soil crack resistance.

Comprehensive evaluation of chemical breakers for multistage network ultra-high strength gel

Polymer gels have been accepted as a useful tool to address many sealing operations such as drilling and completion,well stimulation,wellbore integrity,water and gas shutoff,etc.Previously,we developed an ultra-high strength gel(USGel)for medium to ultra-low temperature reservoirs.However,the removal of USGel is a difficult problem for most temporary plugging operations.This paper first provides new insights into the mechanism of USGel,where multistage network structure and physical entanglement are the main reasons for USGel possessing ultra-high strength.Then the effects of acid breakers,encapsulated breakers,and oxidation breakers(including H_(2)O_(2),Na_(2)S_(2)O_(8),Ca(ClO)_(2),H_(2)O_(2)+NaOH,Na_(2)S_(2)O_(8)+NaOH,and Ca(ClO)_(2)+NaOH)were evaluated.The effects of component concentration and temperature on the breaking solution were studied,and the corrosion performance,physical simulation and formation damage tests of the breaking solution were carried out.The final formulation of 2%-4%NaOH+4.5%-6%H_(2)O_(2) breaking solution was determined,which can make USGel completely turn into water at 35e105C.The combinations of“acid t breaking solution”,“acid+encapsulated breaker”and“encapsulated breaker+breaking solution”were evaluated for breaking effect.The acid gradually reduced the volume of USGel,which increased the contact area between breaking solution and USGel,and the effect of“4%acid+breaking solution”was 23 times higher than that of breaking solution alone at 35C.However,the acid significantly reduced the strength of USGel.This paper provides new insights into the breaking of high-strength gels with complex network structures.

Numerical Study of the Ice Breaking Resistance of the Icebreaker in the Yellow River Through Smoothed-Particle Hydrodynamics

A ship-ice-water interaction model is established using smoothed-particle hydrodynamics(SPH)to predict the ice breaking resistance of the icebreaker in the Yellow River effectively.This method includes the numerical process of the constitutive equation,yield criterion,and the coupling model in SPH.The ice breaking resistance is determined under different conditions.The numerical results of the ice breaking resistance agree with the empirical formula results.Results show that the prediction accuracy of ice resistance is less than 17.6%compared with the empirical formula in the level ice.The method can also be extended to predict the floe motion and ice breaking resistance in actual river channels.The validation against the empirical formula indicates that the proposed ship-ice-water SPH method can predict the ice breaking resistance of icebreakers in actual rivers effectively.The predicted ice breaking resistance is analyzed under different conditions.The ice breaking resistance increases with increasing bending strength and ice thickness,and the latter is the most important factor influencing ice resistance.

Effectiveness of progressive resistance training in improving muscle strength in myasthenia gravis:a single subject study design

Background:To investigate the effectiveness of the progressive resistance training(PRT)using thera band in improving muscle strength in myasthenia gravis(MG).Methods:In this prospective study,12 MG patients with generalised stable disease performed progressive resistance training with thera band for four times per week for 24 weeks.The isometric muscle force of shoulder abductors,biceps brachii and knee extensors using handheld dynamometer,Myasthenia Gravis Composite(MGC)score,Quantitative myasthenia gravis score(QMG),were assessed before and after the training period.Results:Progressive resistance training was well tolerated,and the isometric muscle strength was significantly improved in shoulder abductors,biceps brachii and knee extensors(P<0.05).The disease course(QMG and MGC)was slowed down and improved(P<0.05).Conclusion:Progressive resistance training is effective in improving muscle strength specifically in most affected muscles in MG.

TENSILE-SHEAR STRENGTH AND BREAKING MORPHOLOGY FOR VIBRATION DAMPING LAMINATED STEEL SHEET

The phenolic resin-chloroprene nthher was used for sandwich in manufueturing the vibra-tion damping laminated steel sheet (also calied laminated sheet), Il is a metal matrix com-posite. The tensie-shear tests have been conducted over a range of temperatures from 20C to 150C and at the strain rates from 1.67× 10 ^(5) to 1.67× 10^(-2)s^(-1). The results show that test temperature will significaiilly affect the tensile shear strength of laminated sheet. and a minimal strength and a minimal activation energy occur near 80C . The tensile-shear breaking morphology of laminated sheet varies with strain rate and test temjteralurc.

Combining Ability and Heterosis Between High Strength Lines and Transgenic Bt (Bacillus thuringiensis) Bollworm-Resistant Lines in Upland Cotton (Gossypium hirsutum L.)

To analyse the combining ability and heterosis between high-strength lines and transgenic Bt bollworm-resistant lines in upland cotton, 5 high-strength lines were crossed as female lines with 12 transgenic Bt bollworm-resistant lines according to NCII design. It was demonstrated that the compositions of variance in various traits were quite different. For seed cotton yield, lint yield, boll numbers per plant and boll weight, the dominant (special combining ability) effects were the major effects, accounting for 87.38, 84. 40, 80. 04 and 64. 46% of the total phenotypic variances, respectively, while for fibre strength and micronaire value, the additive (general combining ability) effects had the major effects, with a ratio of additive variance to phenotypic variance of 78.85 and 43.80%. As for lint percent and 2.5% span length, the dominant and additive variances had similar effects, in phenotypic variances (54.94 and 40.11% for lint percent, 45.76 and 42.49% for 2. 5% span length, respectively). The mid-parent heterosis (Hpm), surpassing parent heterosis (Hpb) and competitive heterosis (Hck) for seed cotton yield and lint yield were both extremely significant. For fibre properties, the Hck and Hpm of 2.5 % fibre span length were extremely significant, the Hck of fibre strength was significant, and the favorable negative Hck of micronaire was also extremely significant. The increments of hybrid over common variety were 17% for lint yield and fibre strength, 7% for fibre span length, and 4 % for fineness.

Investigation on the Relationship between Specimen Width and Breaking Strength of Geotextile

The tensile properties of geotextile are analyzed with the boundary element method, with special emphasis put on the influence of specimen width on geotextile breaking strength. The theoretical and experimental results showed that narrow specimen would underestimate the tensile strength of the geotextile. During testing procedure, the lateral contraction of the specimen is the main reason that causes the breaking strength to be on the lower side. The theoretical results also indicate that the breaking strength of the geotextile would arrive at a fixed value when the specimen width is increased to a certain extent.

ON THE RELATIONSHIP BETWEEN TENSILE STRENGTH,BREAKING ELONCATION,CRYSTALLINITY AND ORIENTAHON OF SILK

In this paper,the relation between the tensile strength,breaking elongationand the Crystallinity,Orientation of silk was studied,which obtalned from thecocoons with different silk worm races,sexes,cocooning conditions.The Crystallinity and degree of Crystal Orientation of fibroin were determinedby the X-ray diffraction.and the birefringence of fibroin was measured withInterference microscope.The research showed that the dependence of strength and elongation of rawsilk on Its crystailinity was not so closed.Although there was linear correlation ofstrength with the birefringence and the degree of crystal orientation of fibroin.But the correlation coefficient of the former was larger than the latter.Therefore,adopting birefringence method which would reflected the degree of orlentation ofboth the amorphous and crystalline region of fibroln was suitable for consideringthe strength.The correlation coefficients of strength and elongation withbirefringence were 0.96 and 0.77 respectively.The latter one was

Isolated Lumbar Extension Resistance Training Is Effective at Improving Extension Power and Disability in Subjects with Diagnosed Lumbar Multifidus Dysfunction

Background: Lumbar multifidus dysfunction is a prevalent cause of disability in individuals with lower back pain. Previous research highlights the benefits of isolated lumbar extension training for non-specific lower back pain, however, studies examining its efficacy in lumbar multifidus dysfunction are lacking. Objective: To evaluate the effectiveness of isolated lumbar extension resistance training on disability and strength in individuals with lumbar multifidus dysfunction. Methods: Subjects underwent a physiotherapy led structured rehabilitation program incorporating isolated lumbar extension. Sessions were conducted twice weekly targeting momentary muscular failure with time under load 90 - 120 seconds and progressions aimed at 5 - 10 lbs increments. Outcomes were assessed using the Oswestry Disability Index and lumbar extension strength testing at baseline and after 12 weeks, with statistical analysis using t-test and chi-squared 2 × 2. Results: Forty-five subjects (24 male, 21 female) with a median age of 48 completed the intervention. Improvements were noted in Oswestry Disability Index scores (median pre: 24, post: 15) and maximal lumbar extension strength (median pre: 122 lb, post: 186 lb), with p ≤ 0.05. Overall, 89% showed improvement in disability scores, 67% moved to a better disability category, and 51% saw at least a 50% increase in strength. No significant gender differences were observed. Conclusions: Isolated lumbar extension resistance training is effective at improving extension power and disability in subjects with lumbar multifidus dysfunction.

Strength Acquisition Mechanism of High Temperature Resistant Materials Prepared by Waste Architectural Ceramics

In order to realize the large-scale and high-value utilization of waste architectural ceramics,high-temperature resistant materials based on waste architectural ceramics were prepared with sodium silicate as the binder,clay/bauxite and metakaolin/bauxite as coating materials,and the cold strength obtaining mechanism was explored.The phase composition,the microstructure and the mechanical properties of the high temperature resistant materials based on waste architectural ceramics were tested and analyzed.The results showed that when the heat treatment temperature was between 110-1000℃,the strength of the samples mainly came from the physical adhesion of sodium silicate and fine powder.When the temperature rose to 1100℃,the strength of the sample was improved since the internal low-melting-point components melted and promoted sintering.The addition of clay and bauxite can effectively enhance the flexural strength of the samples when the heat treatment temperature is 1000℃.When the heat treatment temperature rises from 900 to 1000℃,the flexural strength of the samples will be enhanced owing to the formation of silica alumina spinel and mullite from metakaolin.

Pathogenic Variation and Occurrence of Multiple Resistance-Breaking <i>Rice yellow mottle virus</i>Strains in Tanzania

Rice yellow mottle virus (RYMV) is a major biotic constraint for rice production in Africa. The resistance-breaking ability of Tanzanian RYMV strains and phylotypes (S4lm (Tz526), S4lv (Tz516), S4ug (Tz508), S5 (Tz429, Tz445), S6c (Tz486) and S6w (Tz539)) were tested by inoculating rice cultivars with RYMV1 resistant alleles (Gigante (rymv1-2), Tog12387 (rymv1-3), Tog5681 (rymv1-3), Tog5438 (rymv1-4), Tog5672 (rymv1-4+rymv2) and Tog5674 (rymv 1-5)) in a screen house. The results revealed multiple resistance-breaking strains and phylotypes on resistant cultivars Gigante, Tog12387, Tog5438 and Tog5681. However, the resistance breakdown was highly variable depending on the strain used, and disease severity ranged from 11% - 75.3%. The virulence potential of RYMV phylotype S4lm (Tz526) was similar to phylotype S6w (Tz539). The impact of strains and phylotypes on yield and its components in rice cultivars revealed highly significant differences (P ≤ 0.001). The lowest percent plant height reduction (2.8%), number of tillers per plant (2.5%), 1000 grain weight (2.7%), spikelet sterility (3.5%) and yield (5%) was recorded in rice cultivar Gigante inoculated with RYMV phylotype S6c (Tz486). Phylotype S6c (Tz486) despite being less virulent compared to other strains, its virus titer in rice cultivar Gigante (1.833) was higher than S5 (Tz429, Tz445) inoculated on Tog5674 (0.171, 0.207) and S6w (Tz539) inoculated on Tog5681 (0.283). The resistant-breaking strain S5 (Tz445) multiplied in resistant rice cultivar Tog5674 without inducing visible symptoms but showed positive reaction to ELISA with low virus titer. The strain S5 overcame wide range of resistant alleles including rymv1-2, rymv1-3, rymv1-4 and rymv1-5 resistance, with exception of rymv1-4 + rymv2. The current results gave a new perspective for future identification of resistance-breaking mutations through sequencing of the RYMV genome in infected rice cultivars and mutagenesis of an infectious viral clone useful for future RYMV resistant breeding programs.

Edge defect analysis of high-strength corrosion-resistant steel

In this study, a 600 MPa hot-rolled corrosion-resistant steel plate produced by a specific company is investigated. Edge jagged defects and edge surface defects generated on both sides of the strip during production are characterized and analyzed. The results indicate that the distribution of reoxidation granules is located underneath the surface peel and that copper-containing granules diffuse along austenite grain boundaries. This phenomenon combined with the chemical composition and production parameters of a strip indicate that copper brittleness leads to edge jagged defects. However,the surface defects should be attributed to inherent defects on the surface of the strip. Measures that prevent surface oxidation and copper segregation at grain boundaries would likely eliminate these two types of edge defects.

Towards developing Mg alloys with simultaneously improved strength and corrosion resistance via RE alloying

Magnesium(Mg)alloys have received an increasing interest in the past two decades for their tremendous application potential.The strength and corrosion resistance levels of common Mg alloys are still relativity low,and especially they are to be improved simultaneously.The addition of rare earth(RE)to Mg alloys is believed to be beneficial for both the strength and corrosion resistance,and some RE-modified traditional Mg alloys have been studied and some new RE-containing Mg alloys have been developed by now.However,further simultaneous improvements in both strength and anti-corrosion require a better understanding of the behavior and mechanism of RE in Mg alloys.In this review,the common influence mechanisms of RE on mechanical and anti-corrosion properties of Mg alloys are summarized,and the latest research progress of RE-containing Mg alloys with simultaneously improved strength and corrosion resistance are introduced.It is demonstrated that the research on high-strength and high corrosion resistant RE-containing Mg alloys is still immature,and some opinions and suggestions are put forward for the synergetic improvement of the strength and corrosion resistance of Mg alloys,so as to contribute to the further development of Mg alloys with higher performance.

Strength and chloride resistance of blended Portland cement mortar containing palm oil fuel ash and fly ash

This paper presented a study on the strength and chloride resistance of mortars made with ternary blends of ordinary Portland cement （OPC）, ground palm oil fuel ash （POA）, and classified fly ash （FA）. The mortar mixtures were made with Portland cement type I containing 0-40wt% FA and POA. FA and POA with 1wt%-3wt% retained on a sieve No.325 were used. The compressive strength and rapid chloride penetration depth of mortars were determined. The results reveal that the use of ternary blended cements produces good strength mortars. The use of the blend of FA and POA also produces high strength mortars and excellent resistance to chloride penetration owing to the synergic effect of FA and POA. A mathematical analysis and two-parameter polynomial model were presented to predict the compressive strength. The mathematical model correlated well with the experimental results. The computer 3-D graphics of strength of the ternary blended mortars were also constructed and could be used to aid the understanding and the proportioning of the blended system.

Key parameters controlling electrical resistivity and strength of cement treated soils

The improvement of question soils with cement shows great technical, economic and environmental advantages. And interest in introducing electrical resistivity measurement to assess the quality of cement treated soils has increased markedly recently due to its economical, non-destructive, and relatively non-invasive advantages. This work aims to quantify the effect of cement content （aw）, porosity （nt）, and curing time（T） on the electrical resistivity （p） and unconfined compression strength （UCS） of cement treated soil. A series of electrical resistivity tests and UCS tests of cement treated soil specimen after various curing periods were carried out. A modified Archie empirical law was proposed taking into account the effect of cement content and curing period on the electrical resistivity of cement treated soil. The results show that nt/（aw·T） and nt/（aw·T^1/2） ratio are appropriate parameters to assess electrical resistivity and UCS of cement treated soil, respectively. Finally, the relationship between UCS and electrical resistivity was also established.

Effect of kaolin on tensile strength and humidity resistance of a water-soluble potassium carbonate sand core

Water soluble cores(WSCs) have been widely applied in manufacture of complex metal components with hollow configurations or internal channels. However, the WSCs without any additons have low tensile strength and low humidity resistance. The purpose of this study is to prepare a water-soluble potassium carbonate sand core with addition of kaolin by the hot-temping method. The effects of kaolin on tensile strength, humidity resistance, fracture mechanism, as well as the gas evolution and collapsibility of WSCs were investigated. Results show that both the crystal morphology and the fracture mechanism of the inorganic salt are changed under the participation of kaolin, contributing to the increase of the tensile strength and the humidity resistance of the core. With the addition of 3wt.% kaolin, the tensile strength could be increased by a factor of 2, reached 1.50 MPa and the hygroscopic rate could be decreased by 14%, achieved 0.559%(after stored for 8 h), respectively. As the addition amount of kaolin increases from 0wt.% to 3wt.%, the main fracture mechanism changes from a adhesive to a cohesive fracture mechanism. The water-soluble potassium carbonate core obtained has the low gas evolution and excellent collapsibility, which makes it suitable for casting low melting metal with complex cavities and crooked channels.