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Dynamic and electrical responses of a curved sandwich beam with glass reinforced laminate layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 155-178页

作者： N.sHAHVEIsI s.FELI Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

The dynamic responses and generated voltage in a curved sandwich beam with glass reinforced laminate(GRL)layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact(LVI)are *** current study aims to carry out a dynamic analysis on the sandwich beam when the impactor hits the top face sheet with an initial *** the layer analysis,the high-order shear deformation theory(HsDT)and Frostig's second model for the displacement fields of the core layer are *** classical non-adhesive elastic contact theory and Hunter's principle are used to calculate the dynamic responses in terms of *** order to validate the analytical method,the outcomes of the current investigation are compared with those gained by the experimental tests carried out by other researchers for a rectangular composite plate subject to the *** element(FE)simulations are conducted by means of the ABAQUs *** effects of the parameters such as foam modulus,layer material,fiber angle,impactor mass,and its velocity on the generated voltage are reviewed.

关键词： analytical model piezoelectric layer curved sandwich beam glass reinforced laminate(GRL) pliable core low-velocity impact(LVI) classical non-adhesive elastic contact theory

The great catastrophe: causes of the permo-Triassic marine mass extinction

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National science Review 2024年第1期11卷 37-50页

作者： paul B.Wignall David p.G.Bond school of Earth & Environment University of Leeds school of Environmental sciences University of Hull

The marine losses during the permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in south China, have resolved the crisis to a ～55 kyr interval straddling the permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the permian was likely siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(s) and the overwhelming evidence for rapid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

Experimental investigation of radiative heat propagation in a simplified generic packed bed

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particuology 2024年第5期88卷 149-160页

作者： Matthias Tyslik Lukas pörtner siegmar Wirtz Martin schiemann Institute of Energy plant Technology Ruhr-University Bochum44780 BochumGermany

A novel test rig for the investigation of radiative heat transfer in packed beds has been developed and is introduced with representative experimental *** individual components and the calibration are *** generic packed bed is realized in a simplified way by an arrangement of parallel rods,which represent particles in *** this arrangement,electrically heated rods provide the radiation propagating through the rod array to heat the passive counterparts.A sophisticated temperature-control scheme with a large number of thermocouples and infrared-imaging provides in-depth information about heat transfer in the *** radiation intensities are determined with a Fourier-transform infrared spectroscopy,which has been modified and validated for this specific *** order to compare the influence of different surface properties of particles on the heat propagation and surface reflections,rod samples made of stainless steel and magnesium oxide are *** influence of material properties becomes clearly visible by comparing the high radiation intensities resulting from a stainless steel rod array to the same geometry built from magnesium oxide *** addition,the influence of the surface properties is particularly evident in the infrared images since the reflections are significantly higher for the stainless steel samples than for the magnesium oxide *** experimental results in the current work demonstrate the ability of the test rig to provide data with a well-defined accuracy as a validation base for numerical radiation simulations in packed beds.

关键词： Thermal radiation spectral reflections Fourier-transform infrared spectroscopy

Non-participation of asymptomatic candidates in screening protocols reduces early diagnosis and worsens prognosis of colorectal cancer

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World Journal of Gastroenterology 2024年第26期30卷 3198-3200页

作者： sergio pérez-Holanda Office of Regional Viceministry of Health Regional Viceministry of HealthOviedo 33005AsturiasSpain

The Agatsuma et al’s study shows that despite the evidence of the benefits of an early colorectal cancer(CRC)diagnosis,through screening in asymptomatic subjects,up to 50%of candidates reject this option and many of those affected are diagnosed later,in advanced *** efficacy of screening programs has been well-established for several years,which reduces the risk of CRC morbidity and mortality,without taking into account the test used for screening,or other ***,a significant proportion of patients remain unscreened,so understanding the factors involved,as well as the barriers of the population to adherence is the first step to possibly modify the participation *** barriers could include a full range of social and political aspects,especially the type of financial provision of each health *** Japan,health services are universal,and this advantageous situation makes it easier for citizens to access to these services,contributing to the detection of various diseases,including ***,the symptomatic CRC group had a lower early-stage diagnosis rate than the patients detected during follow-up for other comorbidities,and symptomatic and cancer screening groups showed similar early-stage diagnosis.

关键词： Colorectal neoplasms Cancer registry Diagnostic route Cancer screening stage at diagnosis

MXenes for Bioinspired soft Actuators:Advancements in Angle-Independent structural Colors and Beyond

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Nano-Micro Letters 2024年第8期16卷 18-34页

作者： siavash Iravani Rajender s.Varma Independent Researcher W Nazar STBoostan AveIsfahanIran Centre of Excellence for Research in sustainable Chemistry Department of ChemistryFederal University of São CarlosSão CarlosSP 13565‑905Brazil

soft actuators have garnered substantial attention in current years in view of their potential appliances in diverse domains like robotics,biomedical devices,and biomimetic *** actuators mimic the natural movements of living organisms,aiming to attain enhanced flexibility,adaptability,and *** the other hand,angle-independent structural color has been achieved through innovative design strategies and engineering *** carefully controlling the size,shape,and arrangement of nanostructures,researchers have been able to create materials exhibiting consistent colors regardless of the viewing *** promising class of materials that holds great potential for bioinspired soft actuators is MXenes in view of their exceptional mechanical,electrical,and optical *** integration of MXenes for bioinspired soft actuators with angle-independent structural color offers exciting *** material compatibility issues,improving color reproducibility,scalability,durability,power supply efficiency,and cost-effectiveness will play vital roles in advancing these *** perspective appraises the development of bioinspired MXene-centered soft actuators with angleindependent structural color in soft robotics.

关键词： MXenes MXene-based composites Bioinspired soft robotics Angle-independent structural color

Impact of social Determinants of Health on self-perceived Resilience: An Exploratory study of Two Cohorts of Adults with Congenital Heart Disease

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Congenital Heart Disease 2024年第1期19卷 33-48页

作者： Albert Osom Krysta s.Barton Katie sexton Lyndia Brumback Joyce p.Yi-Frazier Abby R.Rosenberg Ruth Engelberg Jill M.steiner Department of Biostatistics University of WashingtonSeattleWA98195USA Biostatistics Epidemiology and Analytics for Research(BEAR)Core Seattle Children’s Research InstituteSeattleWA98101USA College of Medicine University of WashingtonSeattleWA98195USA Center for Clinical and Translational Research Seattle Children’s Research InstituteSeattleWA98101USA Department of psychosocial Oncology and palliative Care Dana-Farber Cancer InstituteDepartment of MedicineBoston Children’s HospitalBostonMA02215USA Department of pediatrics Harvard Medical SchoolBostonMA02215USA Division of pulmonary Critical Care and Sleep MedicineDepartment of Medicine&Cambia Palliative Care Center of ExcellenceUniversity of WashingtonHarborview Medical CenterSeattleWA98104USA Division of Cardiology Department of Medicine&Cambia Palliative Care Center of ExcellenceUniversity of WashingtonSeattleWA98195USA

social determinants of health(sDOH)affect quality of *** investigated sDOH impacts on self-perceived resilience among people with adult congenital heart disease(ACHD).secondary analysis of data from two com-plementary studies:a survey study conducted May 2021–June 2022 and a qualitative study conducted June 2020–August *** was assessed through CD-RIsC10 score(range 0–40,higher scores reﬂect greater self-perceived resilience)and interview *** and sDOH(education,employment,living situa-tion,monetary stability,ﬁnancial dependency,area deprivation index)data were collected by healthcare record review and *** used linear regression with robust standard errors to analyze survey data and performed a thematic analysis of interview *** participants(N=127)mean age was 42±14 years;51%were female,87%*** was moderate(75%)or complex(25%);41%functional class C or ***(mean 30±7)varied by monetary stability:compared to people with difﬁculty paying bills,resilience was 15.0 points higher(95%CI:6.9–23.1,ppeople reporting having enough money and 14.2 points higher(95%CI:5.9–22.4,p=0.001)for those reporting just enough *** participants’(N=25)mean age was 32 years(range 22–44);52%were female,72%*** was moderate(56%)or complex(44%);76%functional class C or *** discussed factors affecting resilience aligned with each of the major sDOH,prominently,economic stability and healthcare access and *** stability may be important for supporting self-perceived resi-lience in *** knowledge can inform the development of resilience interventions for this population.

关键词： social determinants of health adult congenital heart disease resilience ﬁnancial stability

Constraining the variable generalized Chaplygin gas model in matter creation cosmology

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Communications in Theoretical physics 2024年第10期76卷 121-136页

作者： Yogesh Bhardwaj C p singh Department of Applied Mathematics Delhi Technological University

We explore the variable generalized Chaplygin gas（VGCG） model in the theory of matter creation cosmology within the framework of a spatially homogeneous and isotropic flat Friedmann—Lemai tre—Robertson—Walker space-time. Matter creation cosmology is based on reinterpretation of the energy–momentum tensor in Einstein's field equations. This creation corresponds to an irreversible energy flow from the gravitational field to the created matter constituents. The variable Chaplygin gas（VCG） is also studied as a particular solution. We use the Markov chain Monte Carlo method to constrain the free parameters of three models, namely,Lambda-Cold-Dark matter（ΛCDM）, VGCG and VCG models with and without matter creation from the latest observational data from baryon acoustic oscillations, cosmic chronometer, type Ia supernovae（pantheon） including gamma-ray bursts, quasars and the local measurement of H0from R21 data. Two different combinations of dataset provide a fairly tight constraint on the parameters of the ΛCDM, VGCG and VCG models. The present values of various cosmological parameters are obtained, which are very close to the ΛCDM model. Furthermore, we perform stability analysis, Bayesian evidence analysis and information criteria analysis for these models through studying the sound speed, Bayes factor, and Akaike information criteria（AIC） and Bayesian information criteria（BIC） selection criteria. The values of sound speed for VGCG and VCG models shows that both the models are stable. According to AIC, it is observed that VGCG and VCG models with matter creation are supported considerably less by current observations,while BIC shows that these models are not favoured by observational data.

关键词： Chaplygin gas model cosmological model dark energy matter creation

Tensor force impact on shell evolution in neutron-rich si and Ni isotopes

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Chinese physics C 2024年第4期48卷 95-106页

作者： s.V.sidorov A.s.Kornilova T.Yu.Tretyakova Faculty of physics Lomonosov Moscow State UniversityMoscow 119991Russia skobeltsyn Institute of Nuclear physics Lomonosov Moscow State UniversityMoscow 119991Russia

The influence of the tensor interaction of nucleons on the characteristics of neutron-rich silicon and nickel isotopes was studied in this *** forces are considered within the framework of the Hartree-Fock approach with the skyrme *** addition of a tensor component of interaction is shown to improve the description of the splittings between different single-particle states and decrease nucleon-nucleon pairing correlations in silicon and nickel *** attention was directed toward the role of isovector tensor forces relevant to the interaction of like nucleons.

关键词： nuclear shell model tensor interaction silicon isotopes nickel isotopes

The emerging role of exercise as a cancer treatment

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Journal of sport and Health science 2024年第4期13卷 443-444页

作者： Kerry s.Courneya Faculty of Kinesiology Sportand RecreationCollege of Health SciencesUniversity of AlbertaEdmontonAlbertaT6G 2H9Canada

Over the past few decades,exercise oncology has emerged as an important subfield within exercise *** that time,substantial progress has been made in understanding the role of exercise in people newly diagnosed with ca... 详细信息

关键词： cancer treatment exercise