Cardiorespiratory fitness and mortality from all causes, cardiovascular disease and cancer: dose–response meta-analysis of cohort studies

ObjectiveCurrent evidence of the associations between cardiorespiratory fitness (CRF) and mortality is limited. We performed a meta-analysis to assess the dose–response association of CRF with mortality from all causes, cardiovascular disease (CVD) and cancer in healthy population.MethodsPubMed, EMBASE and Web of Science were searched up to 26 December 2019 for reports of cohort studies giving risk estimates for all-cause, CVD and cancer mortality by level of CRF. Cohort studies were included if CRF was assessed by an exercise stress test and reported as at least three levels or per incremental increase, and the association of CRF with all-cause, CVD and cancer mortality was evaluated. Generalised least-squares regression models were used to assess the quantitative relation of CRF with all-cause, CVD and cancer mortality.Results34 cohort studies were eligible for the meta-analysis. The pooled relative risks (RRs) for all-cause, CVD and cancer mortality per one-metabolic equivalent increase in CRF were 0.88 (95% CI 0.83 to 0.93), 0.87 (95% CI0.83 to 0.91) and 0.93 (95% CI 0.91 to 0.96), respectively. As compared with lowest CRF, with intermediate CRF, the summary RRs for all-cause, CVD and cancer mortality were 0.67 (95% CI 0.61 to 0.74), 0.60 (95% CI 0.51 to 0.69) and 0.76 (95% CI 0.69 to 0.84), respectively, and with highest CRF were 0.47 (95% CI 0.39 to 0.56), 0.49 (95% CI 0.42 to 0.56) and 0.57 (95% CI 0.46 to 0.70), respectively.ConclusionOur analysis showed inverse dose–response associations of CRF with all-cause, CVD and cancer mortality, which provides evidence for public health recommendations for preventing all-cause, CVD and cancer mortality.PROSPERO registration numberCRD42020208883.

VOCALIC SYSTEM OF THE NORTH-EASTERN DIALECT OF ENGLAND WITHIN THE PERIOD OF 1990-2000

The article presents the experimental study results of the specificity of the deviations in the vocalic system registered in the pronunciation of the English north-eastern dialect speakers within the period of 1990-2000 years. With the regard to the current tendencies of including dialect not only to the scope of geographic dialectology but also to the scope of sociolinguistics, as well as aiming to provide the detailed study of functionality characteristics of any dialect and the north-eastern dialect of England as a such it was decided to analyse the vocalic system present in the speech of the local men and women who represent different socio-cultural level within the period of 1990-2000. Moreover, it was proven that the period of 1990-2000 is crucial for the development of the dialect under study, since the end of the XXth century witnessed major changes in the development of the society.The nomenclature of segmental units of the north-eastern dialect vocalic system was determined by means of auditory and comparative analyses of segmental phonetic units’ deviations from the orthoepic norm of the English language. The article also presents the percentage rates of the mentioned deviations actualizations as well as gives a graphical interpretation of the quantitative relation between the specific types of deviations in the vowel system and the speakers’ socio-cultural level (high, middle, low) and their sex (the speakers were represented by females and males in the age from 16 to 80 years old). The formed frequency rate matrixes of such deviations show that the social changes which took place in the Northern East of England within the period of 1990-2000 strongly influence the tendency shift of speech standardization among speakers with high and middle socio-cultural levels.

Hydro-Damage Properties of Red-Bed Mudstone Failures Induced by Nonlinear Seepage and Diffusion Effect

Nonlinear catastrophes caused by geological fluids are a fundamental issue in rock mechanics and the geoengineering hazard field. For the consideration of hydrodynamic force on red-bed mudstone softening damage, X-ray visualization test on the fissure flow in mudstone block failure under hydrodynamic force was performed in this study based on block scale and the physical phenomena of fissure seepage and nonlinear diffusion were further explored. A new method for evaluating the hydro-damage degrees of rocks using an X-ray image analysis was proposed, and the quantitative relation of diffusion coefficients of hydro-damage and seepage was established. The research results revealed that the hydrodynamic force promoted the fluid-filled fissure behavior in mudstone specimen failure. Also, the seepage and diffusion phenomena of fluid in rocks during failures were indicated using X-ray imaging. A dual mechanical behavior was presented in the nonlinear seepage and abnormal diffusion of a red mudstone geological body under hydrodynamic conditions. The damaged degree of mudstone was aggravated by the effect of hydrodynamic force, and the initial seepage–diffusion coefficient with respect to lower hydro-damage was larger than the final seepage–diffusion coefficient with respect to higher hydro-damage of rocks with a decreasing nonlinear trend.

A deeper exploration of the relation between sulfonation degree and retanning performance of aromatic syntans

It is well-known that the sulfonation degree (DS) of aromatic syntan is an important factor affecting its retanning performances. But the quantitative relation between DS and syntan property and the influencing mechanism of DS on syntan property are not clarified. In this work, five phenolic formaldehyde syntans (PFSs) with the same polymerization degree but varying DS were prepared to investigate the effect of DS on the properties of syntan and crust leather. It was found that the absolute value of zeta potential and the particle size of PFS decreased with increasing DS in aqueous solution. Molecular dynamic simulation results proved that the DS of PFS was a major contributor to electrostatic interaction and hydrogen bonding in the PFS–water system and greatly affected the aggregation and dispersion of PFS in aqueous solution. The PFS with a low DS was prone to aggregate to large particles in aqueous solution because of low intermolecular electrostatic repulsion and less hydrogen bonds and therefore can be used to increase the thickness and tightness of leather. The PFS with a high DS presented a small particle size with more anionic groups in aqueous solution, thereby sharply decreasing the positive charge of leather surface and facilitating the penetration of the post-tanning agents into the leather. These results might be scientifically valid for rational molecular design of syntans and more productive use of syntans in leather making. Graphical Abstract

Stoichiometry

Stoichiometry is the quantitative relation between the amounts of reactants and products involved in a chemical reaction. The various types of stoichiometric problems are described, and a step-by-step approach for calculating the amounts of reactants and products in a reaction is provided. Further types of calculations include limiting reagents, theoretical yields, and percent yields.

Interspecies variation of larval locomotion kinematics in the genus Drosophila and its relation to habitat temperature

Background Speed and trajectory of locomotion are the characteristic traits of individual species. Locomotion kinematics may have been shaped during evolution towards increased survival in the habitats of each species. Although kinematics of locomotion is thought to be influenced by habitats, the quantitative relation between the kinematics and environmental factors has not been fully revealed. Here, we performed comparative analyses of larval locomotion in 11 Drosophila species. Results We found that larval locomotion kinematics are divergent among the species. The diversity is not correlated to the body length but is correlated instead to the habitat temperature of the species. Phylogenetic analyses using Bayesian inference suggest that the evolutionary rate of the kinematics is diverse among phylogenetic tree branches. Conclusions The results of this study imply that the kinematics of larval locomotion has diverged in the evolutionary history of the genus Drosophila and evolved under the effects of the ambient temperature of habitats.

Design Method for Specific Charge in Deep Mining considering Influence of In Situ Stress

In situ stress has a large influence on blasts in deep mines and should be considered in blasting design. In this study, explosion crater tests were conducted to investigate the variation of specific charges under different stress loading conditions. It was revealed that rock blasting under high stress is different from that under low stress. A correction coefficient for specific charge was defined to consider the influence of in situ stress on blasting. A quantitative relation between the correction coefficient, stress-to-strength ratio, and lateral stress coefficient was presented. Based on the explosion-crater test results, a design method for specific charges was proposed with the consideration of in situ stress. Finally, the design method was applied to a field blasting test at Hongtoushan Copper Mine. The test results indicate that the proposed design method can effectively use the high in situ stress at depth for rock fragmentation. Compared with the original blasting design, the specific charge is reduced by 19.8% and the average block rate is reduced from 6.8% to 2.84%. At the same time, the blasting boundary is well controlled and the ore loss and dilution rates are reduced. This research has important guiding significance to deep mine blasting design.

Incidence of Secondary Microorganism Infections Following Utilization of Tocilizumab for the Treatment of COVID‑19 - A Matched Retrospective Cohort Study

Introduction: immunological disorder agent’s area unit theorized to focus on the protein storm syndrome in COVID‑19. However, the downstream effects concerning susceptibilities to secondary infection risk stay unknown. This study seeks to work out risk variations for secondary infections among COVID‑19 patients World Health Organization did and failed to receive tocilizumab. Methods: we have a tendency to conducted a matched retrospective cohort study from 2 giants, acute care hospitals in Western Connecticut from March 1 to May 31, 2020. we have a tendency to collected variables exploitation manual case history abstraction. the first exposure variable was any dose of tocilizumab. the first outcome was any healthcare‑associated microorganism or mycosis as outlined by the National Care Safety Network. we have a tendency to performed a Kaplan–Meier analysis to assess the crude distinction within the additive likelihood of healthcare‑associated infection (HAI) across exposure teams. we have a tendency to conjointly performed a multivariable Cox multivariate analysis to work out the hazard quantitative relation for HAI by exposure group whereas dominant for potential confounders. Results: The Kaplan–Meier analysis incontestable no distinction within the additive likelihood of HAI across teams. The adjusted hazard of HAI for patients given tocilizumab was zero.85 times that of patients not given tocilizumab (95% confidence interval = zero.29, 2.52, P = 0.780) once dominant for relevant confounders. Conclusions: Tocilizumab failed to increase the incidence of secondary infection among COVID‑19 patients. Larger, irregular trials ought to valuate infection as a secondary outcome to validate this finding.

Investigation on Shear Wave Velocity and Triaxial Mechanical Performance of Tailings Core from Tailings Dam

The physical and mechanical parameters of tailings are important to study the stability of tailings dams (TDs). In this study, a series of laboratory experiments (shear wave velocity, triaxial compressive, and peak strain strength testing) were conducted to obtain the mechanical properties of tailings from TD. The results showed the following. (1) The linear function fitting could characterize the quantitative relationship between shear wave velocity and hole depth. (2) The corresponding static pressure coefficient increased as the confining pressure increased. The exponential fitting could characterize the quantitative function relation between the static pressure coefficient and the confining pressure. (3) The cohesion and internal friction angle of the tailings sample were 20 kPa and 41°, respectively, and the logarithmic fitting could better characterize the quantitative relation between shear peak strength and confining pressure. The results of this study can provide important references for further research on the stability of TD.