Numerical simulation of influence of shear dilatancy on deformation characteristics of shear band-elastic body system

The paper was numerically focused on investigation of deformation, failure and instability of shear band-surrounding elastic rock system in plane strain direct shear test considering shear dilatancy according to fast lagrangian analysis of continua (FLAC). The adopted failure criterion was a composite Mohr-Coulomb criterion with tension cut-off and post-peak constitutive relation of rock, i.e. linear strain-softening. Numerical results show that dilation angle affects the responses of elements, the number and the position of yielded elements. Increasing dilation angle results in higher load-carrying capability of elements, higher deformation or strain corresponding to peak stress, less brittle post-peak stress-deformation curve. Strain-hardening behavior can occur if dilation angle is high. Therefore, shear band-elastic rock body system tends to be stable and rock burst does not occur as dilation angle is increased. Moreover, the number of yielded elements is in- creased with dilation angle increase and two parallel plastic zones initially generated in the middle of two loading ends of specimen no longer remain collinear, reflecting increase in deformation resistant of the system. Evolution of volumetric strain rate was investigated based on three-dimensional curved surface diagrams. Approximately, volumetric strain rate concentration regions coincide with plastic zones. Volumetric strain rate in yielded elements is very evident. However, in elastic zones volumetric strain has not been nearly changed throughout the numerical tests.

Shear stress distribution and characteristics of deformation for shear band-elastic body system at pre-peak and post-peak

The distributed shear stress and the displacement across shear band, the evolution of plastic zones, and the load-carrying capacity of rock specimen were investigated in plane strain direct shear test according to Fast Lagrangian Analysis of Continua （FLAC）. And then the shear displacement distribution in normal direction of system composed of localized shear band and elastic rock was analyzed based on gradient-dependent plasticity. The adopted failure criterion was a composite of Mohr-Coulomb criterion, that is, the relation between tension cut-off and postpeak constitutive of rock was linear strain-softening. Numerical results show that shear stress field approximately undergoes three different stages. At first, shear stress is only concentrated in the middle of top and base of specimen. Next, shear stress in the middle of specimen tends to increase, owing to superposition of shear stresses. Interestingly, two peaks of shear stress appear far from the loading ends of specimen, and the peaks approach with the increase in timestep until elements at the center of specimen yield. Finally, relatively lower shear stress level is reached in large part of specimen except in the regions near the two ends. As flow stress decreases, the analytical shear displacement distribution in shear band based on gradient-dependent plasticity becomes steeps outside the band, it is linear and its slope tends to decrease. These theoretical results qualitatively agree with that of the present numerical predicted results. Main advantage of the analytical solution over the numerical results according to FLAC is that it is continuous, smooth and non-linear （except at elastic stage）.

DYNAMICS OF FLEXIBLE MULTIBODY SYSTEMS WITH TREE TOPOLOGIES

The dynamic equations of flexible multibody systems with tree topological configuration are de- rived by using the Jourdain's principle.The independent joint coordinates are introduced to describe the large displacements of the bodies,and the modal coordinates are used to describe small deformations of flexible bodies based on the consistent mass finite element method and normal vibration mode analysis.The mini- mum differential equations are developed,which are compatible with the equations of multi-rigid body sys- tems or structural dynamics.The stiff problem in the numerical integration is thus alleviated effectively.The method used in this paper can be extended to deal with systems with other topological configurations. Finally,the validity and feasibility of the presented mathematical model are demonstrated by a numerical ex- ample of a manipulator with two elastic links.

The relation between a black hole and a general black body system

Taking a black hole as a black body system, using general black body radiation theory, a Schwarzschild black hole and a Kerr-Newman black hole are investigated respectively. It is concluded that a black hole can be regarded as an ideal general black body system exactly for the changing process only. However, a stationary global black hole cannot be smoothly regarded as a general black body system. A black hole has some special characteristics which different from a general thermodynamics system. This conclusion means that a black hole should be inherently dynamical, at least when it is taken as a black body system.

The Challenges and Opportunities of Buddhist Music Discipline in a New Era-The Practice and Application of Mind and Body System in Chinese Buddhist Chanting

Religious music is an inevitable and important topic when exploring the significance of the“new”or“deep”dimension of religion or spirituality.Traditional Chinese culture influenced Chinese Buddhist chanting practices,developing special melodies,languages,and meaning,and establishing special mind and body practice system spanning thousands of years.Advances in music therapy,meditation,and vocal research give the Chinese Buddhist chanting mind and body practice system enough theoretical support to facilitate the construction of the discipline in the modern era.This paper adopts the scientific approach to tracing and analyzing the origins of the body and mind system in Chinese Buddhist chanting practice and reviews how the system benefits the mind and body and modern society in general.This paper also examines the issues confronting the standard and development of special chanting skills in Chinese Buddhist music in the modern era.

Impact of body mass index on adverse kidney events in diabetes mellitus patients: A systematic-review and meta-analysis

BACKGROUND The incidence of chronic kidney disease among patients with diabetes mellitus(DM)remains a global concern.Long-term obesity is known to possibly influence the development of type 2 diabetes mellitus.However,no previous meta-analysis has assessed the effects of body mass index(BMI)on adverse kidney events in patients with DM.AIM To determine the impact of BMI on adverse kidney events in patients with DM.METHODS A systematic literature search was performed on the PubMed,ISI Web of Science,Scopus,Ovid,Google Scholar,EMBASE,and BMJ databases.We included trials with the following characteristics:(1)Type of study:Prospective,retrospective,randomized,and non-randomized in design;(2)participants:Restricted to patients with DM aged≥18 years;(3)intervention:No intervention;and(4)kidney adverse events:Onset of diabetic kidney disease[estimated glomerular filtration rate(eGFR)of<60 mL/min/1.73 m2 and/or microalbuminuria value of≥30 mg/g Cr],serum creatinine increase of more than double the baseline or end-stage renal disease(eGFR<15 mL/min/1.73 m2 or dialysis),or death.RESULTS Overall,11 studies involving 801 patients with DM were included.High BMI(≥25 kg/m2)was significantly associated with higher blood pressure(BP)[systolic BP by 0.20,95%confidence interval(CI):0.15–0.25,P<0.00001;diastolic BP by 0.21 mmHg,95%CI:0.04–0.37,P=0.010],serum albumin,triglycerides[standard mean difference(SMD)=0.35,95%CI:0.29–0.41,P<0.00001],low-density lipoprotein(SMD=0.12,95%CI:0.04–0.20,P=0.030),and lower high-density lipoprotein(SMD=–0.36,95%CI:–0.51 to–0.21,P<0.00001)in patients with DM compared with those with low BMIs(<25 kg/m2).Our analysis showed that high BMI was associated with a higher risk ratio of adverse kidney events than low BMI(RR:1.22,95%CI:1.01–1.43,P=0.036).CONCLUSION The present analysis suggested that high BMI was a risk factor for adverse kidney events in patients with DM.

Automated body composition analysis system based on chest CT for evaluating content of muscle and adipose

Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were collected(segmented dataset),and chest CT data of 984 patients were screened from the COVID 19-CT dataset(10 cases were randomly selected as whole test dataset,the remaining 974 cases were selected as layer selection dataset).T7—T8 layer was classified based on convolutional neural network(CNN)derived networks,including ResNet,ResNeXt,MobileNet,ShuffleNet,DenseNet,EfficientNet and ConvNeXt,then the accuracy,precision,recall and specificity were used to evaluate the performance of layer selection dataset.The skeletal muscle(SM),subcutaneous adipose tissue(SAT),intermuscular adipose tissue(IMAT)and visceral adipose tissue(VAT)were segmented using classical fully CNN(FCN)derived network,including FCN,SegNet,UNet,Attention UNet,UNET++,nnUNet,UNeXt and CMUNeXt,then Dice similarity coefficient(DSC),intersection over union(IoU)and 95 Hausdorff distance(HD)were used to evaluate the performance of segmented dataset.The automatic body composition analysis system was constructed based on optimal layer selection network and segmentation network,the mean absolute error(MAE),root mean squared error(RMSE)and standard deviation(SD)of MAE were used to evaluate the performance of automatic system for testing the whole test dataset.Results The accuracy,precision,recall and specificity of DenseNet network for automatically classifying T7—T8 layer from chest CT images was 95.06%,84.83%,92.27%and 95.78%,respectively,which were all higher than those of the other layer selection networks.In segmentation of SM,SAT,IMAT and overall,DSC and IoU of UNet++network were all higher,while 95HD of UNet++network were all lower than those of the other segmentation networks.Using DenseNet as the layer selection network and UNet++as the segmentation network,MAE of the automatic body composition analysis system for predicting SM,SAT,IMAT,VAT and MAE was 27.09,6.95,6.65 and 3.35 cm 2,respectively.Conclusion The body composition analysis system based on chest CT could be used to assess content of chest muscle and adipose.Among them,the UNet++network had better segmentation performance in adipose tissue than SM.

ON THE KINEMATIC GEOMETRY OF MANY BODY SYSTEMS

In mechanics, both classical and quantum, one studies the profound interaction betweentwo types of energy, namely, the kinetic energy and the potential energy. The former can beorganized as the kinematic metric on the configuration space while the latter can be representedby a suitable potential function, such as the Newtonian potential in celestial mechanics andthe Coulomb potential in quantum mechanics of atomic and molecular physics. In this paper,the author studies the kinematic geometry of n-body systems. The main results are (i) theintroduction of a canonical coordinate svstem which reveals the total amount of kinematicsymmetry by an SO(3) x O(n-1) action in such a canonical coordinate representationt (ii) anin depth analysis of the above kinematic system both in the setting of classical invariant theoryand by the technique of equivariant Riemannian geometry; (iii) a remarkably simple formulafor the potential function in such a canonical coordinate system which reveals the well-fittingbetween the kinematic symmetry and the Potential energy.

交互式数字叙事:加拿大Writing New Body Worlds阅读治疗新探索

文章基于相关研究文献与语料,对加拿大WNB阅读治疗实践进行梳理与归纳。WNB首次使用交互式数字叙事技术,构建面向公众的阅读治疗平台,以其交互式特征,融合了阅读和治疗引导两个过程,提供可访问的非临床方式,可面向大规模人群实现预防性健康干预。基于数据与计算的精准化阅读治疗是数字人文视角下的新变革,更具推广应用价值;以在线阅读平台建设为依托,推进实施平台化的阅读和治疗应成为未来发展方向之一;基于阅读形态与体验因技术赋能而改变的现状,图书馆应发挥引领作用,积极收集、创建或协助创建数字故事,推进阅读推广、服务与治疗的融合性发展,成为社区建设促进者、历史欣赏者和社区参与倡导者,也使阅读借助交互式数字叙事这一新载体,更好地发挥变革的力量,促进健康与幸福。

Body armour-New materials, new systems

This is a very timely review of body armour materials and systems since new test standards are currently being written, or reviewed, and new, innovative products released. Of greatest importance, however, is the recent evolution, and maturity, of the Ultra High Molecular Weight Polyethylene fibres enabling a completely new style of system to evolve e a stackable system of Hard Armour Plates. The science of body armour materials is quickly reviewed with emphasis upon current understanding of relevant energy-absorbing mechanisms in fibres, fabrics, polymeric laminates and ceramics. The trend in ongoing developments in ballistic fibres is then reviewed, analysed and future projections offered. Weaknesses in some of the ceramic grades are highlighted as is the value of using cladding materials to improve the robustness, and multi-strike performance, of Hard Armour Plates. Finally, with the drive for lighter, and therefore smaller, soft armour systems for military personnel the challenges for armour designers are reported, and the importance of the relative size of the Hard Armour Plate to the Soft Armour Insert is strongly emphasised.

The numerical method for three-dimensional impact with friction of multi-rigid-body system

The differential equations for planar impacts reduce to an algebraic form, and can be easily solved. For three dimensional impacts with friction, there is no closed-form solution, and numerical integration is required due to the swerve behavior of tangential impulse during collisions. The dynamic governing equations in the impact process are built up in impulse space based on the Lagrangian equation in this paper. The coefficient of restitution defined by Poisson is used as the condition of impact termination. A valid nu- merical method for solving three-dimensional frictional impact of multi-rigid body system is established. The singular cases of tangential movement in sticking point are especially noticed and analyzed. Several examples are present to reveal the different kinds of tan- gential movement modes varied with the normal impulse during collision.

Influence of stocking density on growth, body composition and energy budget of Atlantic salmon Salmo salar L. in recirculating aquaculture systems

Atlantic salmon Salmo salar were reared at four stocking densities--high density D1 （final density -39 kg/m^3）, medium densities DE （-29 kg/m^3） and D3 （~19 kg/m^3）, and low density D4 （-12 kg/m^3）- for 40 days to investigate the effect of stocking density on their growth performance, body composition and energy budgets. Stocking density did not significantly affect specific growth rate in terms of weight （SGRw） but did affect specific growth rate in terms of energy （SGRe）. Stocking density significantly influenced the ration level （RLw and RLe）, feed conversion ratio （FCRw and FCRe） and apparent digestibility rate （ADR）. Ration level and FCRw tended to increase with increasing density. Fish at the highest density D~ and lowest density D4 showed lower FCRe and higher ADR than at medium densities. Stocking density significantly affected protein and energy contents of the body but did not affect its moisture, lipid, or ash contents. The expenditure of energy for metabolism in the low-density and high-density groups was lower than that in the medium-density groups. Stocking density affected energy utilization from the feces but had no effect on excretion rate. The greater energy allocation to growth at high density and low density may be attributed to reduced metabolic rate and increased apparent digestibility rate. These findings provide information that will assist selection of suitable stocking densities in the Atlantic-salmon-farming industry.

Association between metabolic syndrome and body constitution of traditional Chinese medicine:A systematic review and meta-analysis

Background:The constitution theory of traditional Chinese medicine(TCM)states that body constitution and disease are associated;therefore,the identification of body constitution can provide reference for disease prevention and treatment.A series of clinical studies evaluating the association between TCM constitution and metabolic syndrome(MetS)have been conducted in recent years.The aim of this systematic review is to summarize and evaluate the clinical evidence of the relationship between constitution and MetS.Methods:The PubMed,Embase,China National Knowledge Infrastructure(CNKI),Chongqing VIP,and Wanfang Data electronic databases were searched from April 2009 to July 2020.The search terms included“metabolic syndrome,”“constitution,”and“Chinese medicine.”Observational studies evaluating the relationship between body constitution of TCM and MetS were included.The primary outcome included the distribution of constitutional types in the MetS population,and odds ratio(OR)or relative risk(RR)between constitution and MetS.Effect size was expressed as proportion or OR with 95%confidence interval(CI).Methodological quality of included studies was evaluated by the NewcastleeOttawa Scale(NOS)or the American Agency for Healthcare Research and Quality(AHRQ)criteria.Results:Three caseecontrol and 26 cross-sectional studies involving 30435 cases were included.Phlegm-dampness,qi-deficiency,and damp-heat were the main constitution types in patients with MetS,accounting for 29%(22%e39%),18%(13%e24%),and 12%(9%e17%)of the population,respectively;the risk of MetS in people with phlegm-dampness and qi-deficiency constitution was 1.74[1.27,2.38]and 1.29[1.01,1.65]times higher than that in those with other constitutions.There were sex-and age-related differences in the distribution of TCM constitution in patients with MetS.Conclusion:Phlegm-dampness and qi-deficiency were associated with the occurrence of MetS.Welldesigned cohort and caseecontrol studies are needed to provide evidence for the use of TCM to prevent and treat MetS.

Association of systemic inflammation and body mass index with survival in patients with resectable gastric or gastroesophageal junction adenocarcinomas

Objective:The systemic inflammation index and body mass index(BMI)are easily accessible markers that can predict mortality.However,the prognostic value of the combined use of these two markers remains unclear.The goal of this study was therefore to evaluate the association of these markers with outcomes based on a large cohort of patients with gastric cancer.Methods:A total of 2,542 consecutive patients undergoing radical surgery for gastric or gastroesophageal junction adenocarcinoma between 2009 and 2014 were included.Systemic inflammation was quantified by the preoperative neutrophil-to-lymphocyte ratio(NLR).High systemic inflammation was defined as NLR≥3,and underweight was defined as BMI<18.5 kg/m2.Results:Among 2,542 patients,NLR≥3 and underweight were common[627(25%)and 349(14%),respectively].In the entire cohort,NLR≥3 or underweight independently predicted overall survival(OS)[hazard ratio(HR):1.236,95%confidence interval(95%CI):1.069–1.430;and HR:1.600,95%CI:1.350–1.897,respectively]and recurrence-free survival(RFS)(HR:1.230,95%CI:1.054–1.434;and HR:1.658,95%CI:1.389–1.979,respectively).Patients with both NLR≥3 and underweight(vs.neither)had much worse OS(HR:2.445,95%CI:1.853–3.225)and RFS(HR:2.405,95%CI:1.802–3.209).Furthermore,we observed similar results in subgroup analyses according to pathological stage,age,and postoperative chemotherapy.Conclusions:Our results showed that preoperative elevated NLR and decreased BMI had a significant negative effect on survival.Underweight combined with severe inflammation could enhance prognostication.Taking active therapeutic measures to reduce inflammation and increase nutrition may help improve outcomes.

3D body解剖软件联合PACS系统在骨科临床实践教学中的应用

目的探讨3D body解剖软件结合医学影像存档与通信系统(PACS)在骨科临床实践教学中的应用效果。方法选择2023年1月至2023年12月在浙江大学医学院附属邵逸夫医院骨科轮转的60名实习生,按照随机数字表法分成实验组和对照组,每组30名。对照组采用传统线上结合线下的混合式教学方法,实验组采用3D body解剖软件联合PACS系统带教模式。在实习期结束时,对两组实习生进行闭卷理论考试与临床实践操作考核,并采用问卷调查方式评估实习生对课程的满意度。结果实验组实习生的理论考试与临床实践操作成绩均高于对照组,差异均有统计学意义(t分别=6.59、4.22,P均<0.05)。实验组实习生在学习兴趣、教学难度、专业能力以及医患沟通能力提升方面的满意度均高于对照组,差异均有统计学意义(χ^(2)分别=9.93、3.77、6.94、8.52,P均<0.05)。结论3D body解剖软件联合PACS系统带教模式运用到骨科实习生的临床教学中,能帮助实习生提高学习兴趣以及医患沟通能力,加强对骨科知识的掌握,降低知识的理解难度,对于提升临床医学教学质量具有重要意义。

The effects of application of an ancient type of acupuncture needle on body temperature, immune function and the autonomic nerve system

The di-zhen (DZ) is an ancient type of acupuncture needle with a history dating back more than 2000 years. Unlike modern acupuncture needles, the DZ is not inserted subcutaneously, and is safely and commonly used at the bedside. The mechanisms underlying its effects are not known. In this study, we measured sublingual and cutaneous body temperature, pulse rate, oxygen pressure (PO2), oxygen saturation (sO2) and carbon dioxide pressure (PCO2) before and after DZ application in 25 healthy male volunteers. Serum levels of catecholamines (adrenaline, noradrenaline and dopamine) and white blood cells (WBCs;ratio and number) were traced for one week. Soon after DZ application, pulse rate, body temperature, PO2 and sO2 all decreased. The serum levels of adrenaline and noradrenaline increased, indicating sympathetic dominance, and the number of granulocytes was elevated. One week after DZ application, the number of lymphocyte increased. We therefore suggest that DZ affects body temperature, pulse rate, catecholamine secretion and immune function by inducing transient sympathetic dominance via actions on the autonomic nervous system. These effects are similar to the effects observed with modern needles, which are inserted subcutaneously. Therefore, we consider DZ treatment to be advantageous and safe in modern clinical practice, especially in post-surgical and terminal care, as it avoids the issues with infection and tissue damage sometimes seen with modern acupuncture needles.

Association between pre-pregnancy body mass index and gestational weight gain and the risk of preeclampsia:A systematic review and meta-analysis

Objective:To analyze the relationship between body mass index(BMI)before pregnancy and gestational weight gain throughout pregnancy with the incidence of preeclampsia.Methods:This was a systematic review-meta analysis of literature collected from three e-databases:Scopus,PubMed,and Science Direct.Quality assessment was measured with the Effective Public Health Practice Project methods.Meta-analysis was done by calculating the fixed and random-effects of odds ratio(OR)for each BMI category and gestational weight gain as compared with the incidence of preeclampsia.Results:Overweight was associated with a significantly increased risk of preeclampsia(OR=2.152,95%CI 1.363-3.400;P=0.001).Obesity was also associated with a noticeably increased risk of preeclampsia(OR=2.856,95%CI 1.755-4.649;P<0.001).Meanwhile,underweight was associated with a significantly reduced risk of preeclampsia(OR=0.639,95%CI 0.500-0.817;P<0.001)when compared with normal BMI.Pregnant women who gained weight below the standard throughout pregnancy was a protective factor from preeclampsia(OR=0.813,95%CI 0.610-1.083;P=0.157)whereas pregnant women who gained weight above the standard had almost doubled risk of preeclampsia(OR=1.850,95%CI 1.377-2.485;P<0.001).Conclusions:The result of this study affirms the role of overweight-obesity pre-pregnancy,and gestational weight gain above the standard during pregnancy as significant risk factors for developing preeclampsia.

Critical interfaces in body armour systems

The ballistic performance,and behaviour,of an armour system is governed by two major sets of variables,geometrical and material.Of these,the consistency of performance,especially against small arms ammunition,will depend upon the consistency of the properties of the constituent materials.In a body armour system for example,fibre diameter,areal density of woven fabric,and bulk density of ceramic are examples of critical parameters and monitoring such parameters will form the backbone of associated quality control procedures.What is often overlooked,because it can fall into the User’s domain,are the interfaces that exist between the various products;the carrier,the Soft Armour Insert(SAI),and the one or two hard armour plates(HAP1 and HAP2).This is especially true if the various products are sourced from different suppliers.

MobiHealthcare System: Body Sensor Network Based M-Health System for Healthcare Application

M-health, which is known as the practice of medical and public health supported by mobile devices such as mobile phones and PDAs for delivering medical and healthcare services, is currently being heavily developed to keep pace with the continuously rising demand for personalized healthcare. To this end, the MobiHealthcare system, which provides a personalized healthcare based on body sensor network, is developed. The system includes various body sensors to collect physiological signals specifically for different requirements, a cell phone to facilitate the joint processing of spatially and temporally collected medical data from different parts of the body for resource optimization and systematic health monitoring, a server cluster with great data storage capacity, powerful analysis capabilities to provide data storage, data mining and visualization. Compared with existing M-Health system, the MobiHealthcare system is characteristics of low coupling and powerful parallel computing capabilities. Various healthcare applications have been implemented in the proposed system to demonstrate its effectiveness in providing a powerful platform.

A Numerical Study on Water Waves Generated by A Submerged Moving Body in A Two-Layer Fluid System

This is a numerical study on the time development of surface waves generated by a submerged body moving steadily in a two-layer fluid system, in which a layer of water is underlain by a layer of viscous mud. The fully nonlinear Navier- Stokes equations are solved on FLUENT with the Volume-of-Fluid （VOF） mnltiphase scheme in order to simulate, the free surface waves as wen as the water-mud interface waves as functions of time. The numerical model is validated by mimicking a reported experiment in a one-layer system before it is applied to a two-layer system. It is found that the presence of bottom mud in a water layer can lead to large viscous damping of the surface waves. For the investigation of the problem systematically, the effects of the Froude number and the mud layer thickness, density and viscosity relative to those of water are evaluated and discussed in detail.