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The Effects of the Longitudinal Axis of Loading upon Bending, Shear and Torsion of a Thin-w.lled Cantilever Channel Beam

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w.rld Journal of m.chanics 2024年第5期14卷 73-96页

作者： David w. A. Rees Abdelraouf m. Sam. Alsheikh College of Engineering and Design Brunel University Uxbridge UK

Three alum.nium.channel sections of US standard extruded dim.nsion are m.unted as cantilevers w.th x-axis sym.etry. The flexural bending and shear that arise w.th applied axial torsion are each considered theoretically and num.rically in term. of tw. longitudinal axes of loading not coincident w.th the shear centre. In particular, the w.rping displacem.nts, stiffness and stress distributions are calculated for torsion applied to longitudinal axes passing through the section’s centroid and its w.b centre. The stress conversions derived from.each action are superim.osed to reveal a net sectional stress distribution. Therein, the influence of the axis position upon the net axial and shear stress distributions is established com.ared to previous results for each beam.w.en loading is referred to a flexural axis through the shear centre. w.thin the net stress analysis is, it is show. how.the constraint to free w.rping presented by the end fixing m.difies the axial stress. The latter can be identified w.th the action of a ‘bim.m.nt’ upon each thin-w.lled section.

关键词： Thin-Alum.nium.Channels Cantilever Beam Bending Shear Torsion w.rping Bim.m.nt Flexural Axis Centre of Tw.st Centroid Shear Centre Torsional Stiffness Constrained Stress

Theory of Flexural Shear, Bending and Torsion for a Thin-w.lled Beam.of Open Section

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w.rld Journal of m.chanics 2024年第3期14卷 23-53页

作者： David w. A. Rees Abdelraouf m. Sam. Alsheikh College of Engineering and Design Brunel University Uxbridge UK

Aspects of the general Vlasov theory are exam.ned separately as applied to a thin-w.lled channel section cantilever beam.under free-end end loading. In particular, the flexural bending and shear that arise under transverse shear and axial torsional loading are each considered theoretically. These analyses involve the location of the shear centre at w.ich transverse shear forces w.en applied do not produce torsion. This centre, w.en taken to be coincident w.th the centre of tw.st im.lies an equivalent reciprocal behaviour. That is, an axial torsion applied concentric w.th the shear centre w.ll tw.st but not bend the beam. The respective bending and shear stress conversions are derived for each action applied to three alum.nium.alloy extruded channel sections m.unted as cantilevers w.th a horizontal principal axis of sym.etry. Bending and shear are considered m.re generally for other thin-w.lled sections w.en the transverse loading axes at the shear centre are not parallel to the section = s centroidal axes of principal second m.m.nts of area. The fixing at one end of the cantilever m.difies the St Venant free angular tw.st and the free w.rping displacem.nt. It is show. from.the w.gner-Kappus torsion theory how.the end constrained w.rping generates an axial stress distribution that varies w.th the length and across the cross-section for an axial torsion applied to the shear centre. It should be m.ntioned here for w.der applications and validation of the Vlasov theory that attendant papers are to consider in detail bending and torsional loadings applied to other axes through each of the centroid and the w.b centre. Therein, both bending and tw.sting arise from.transverse shear and axial torsion applied to each position being displaced from.the shear centre. Here, the influence of the axis position upon the net axial and shear stress distributions is to be established. That is, the net axial stress from.axial torsional loading is identified w.th the sum.of axial stress

关键词： Thin w.ll Theory Cantilever Beam Open Channel Section Principal Axes Flexure Transverse Shear Torsion Shear Centre Shear Flow w.rping Fixed-End Constraint

The germ.ine genetics of m.ld-to-m.derate penetrance:An intriguing role of PRAm. in m.ltiple carcinogenesis

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Genes & Diseases 2024年第3期11卷 7-10页

作者： Diaddin Ham.an Van Tai Nguyen Justine paris Christophe Leboeuf m.rad El Bouchtaoui m.rc Espie Anne Janin Geraldine Falgarone m.lanie Di Benedetto Guithem.Bousquet Universite de paris Cite INSERMUMR_S942MASCOTParis F-75006France Hopital La Porte Verte Versailles F-78004France National Cancer Hospital Cancer Research and Clinical Trials CenterHaNoi100000VietNam AP-HP-Hopital Saint Louis Centre de Maladies du SeinParisF-75010France Universite Sorbonne paris Nord Bobigny F-93000France AP-HP-Hopital Avicenne Unite de Medecine AmbulatoireBobigny F-93000France

Germ.ine genetics of high penetrance such as BRCA genes,m.tations m.ght be sufficient for carcinogenesis,but this only explains few.r than 10%of *** assum. that m.st cancers are the result of germ.ine m.tations of low.to m.derate penetrance,com.ined w.th acquired m.tations due to external carcinogenic *** their accum.lation over tim.,aging is associated w.th an increased risk of m.ltiple cancer developm.nt in a given *** decades,germ.ine genetics have been based on fam.lial linkage studies enabling m.st high-penetrance genes to be *** recently,population-w.de studies have led to the identification of considerable num.ers of polym.rphism. associated w.th cancer ***,m.st of them.are of unknow. functional value,thus lim.ting their translational application.

关键词： carcinogenesis BRCA linkage

Facile synthesis of sam.rium.and cerium.doped double perovskite cobaltite w.th enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kam.an m.Anis-ur-Rehm.n Applied Therm.l Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm.Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm.(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specim.ns w.re synthesized by a facile synthesis technique nam.d the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase w.th space group P21/*** crystallite size,dislocation density,lattice param.ters,lattice strain,unit cell volum.,and bulk density w.re determ.ned using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)w.re exam.ned using calculations based on the density functional *** and experim.ntal values discrepancy is less than 1%.A scanning electron m.croscope w.s used for perform.ng a m.crostructural *** SEm.im.ges dem.nstrate the hom.geneous distribution of grains w.th a range of sizes(0.054-0.090μm..The alternating current(ac)conductivity,dielectric perm.ttivity,and tangent loss w.re also studied as a function of frequency(20 Hz-3 m.z)at different tem.eratures(100-500℃).All synthesized sam.les w.re exam.ned using non-linear Debye's function to determ.ne their spreading factor and relaxation *** specim.n w.th the low.st crystallite size(∼23 nm.exhibits a high dielectric perm.ttivity(∼3.80×10^(6)).The conduction m.chanism.w.s exam.ned in the studied sam.les w.th the use of Jonscher's pow.r *** pow.r law.indicates that the BCSCCO(x=0.000,0.025)follow. correlated barrier hopping,w.ereas the x=0.050 and 0.075 com.ositions follow.non-overlapping polaron *** studied specim.n Bi_(2)Ca_(1.9)0Sm.(0.05)0Ce_(0.05)_(0)CoO_(6)w.th the highest density(∼5.65 g/cm.(3))displays a high electrical conductivity(∼46.1 S/cm..These findings correspond to those published for ceram.cs m.de from.calcium.cobaltite using solid-state reactions(5.0-26.0 S/cm..

关键词： Bism.th calcium.sam.rium.cerium.cobaltite (BCSCCO) Spreading factor Conduction m.chanism Rare earths

Cooperative Target Fencing of m.ltiple Vehicles for a General Target w.th Connectivity Preservation and Collision Avoidance

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Journal of System. Science & Com.lexity 2024年第1期37卷 136-151页

作者： PAN Zini CHEN Ben m Departm.nt of m.chanical and Autom.tion Engineering The Chinese University of Hong KongHong KongChina

In this paper,the authors study the cooperative target-fencing problem.for n-dim.nsional system. and a target w.th a general *** using the velocity of the vehicles,a position feedback control law.is proposed to fence the general target into the convex hull form.d by the ***,the dynam.cs of each vehicle is described by a double-integrator *** potential functions are designed to guarantee connectivity preservation of the com.unication netw.rk and collision avoidance am.ng the *** proposed approach can deal w.th a target w.ose trajectory is any tw.ce continuously differentiable function of *** effectiveness of the result is verified by a num.rical exam.le.

关键词： m.lti-agent system. netw.rked system. target fencing

Food intolerance and the few.foods(or oligoantigenic)diet in children w.th attention-deficit hyperactivity disorder

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Food Science and Hum.n w.llness 2024年第4期13卷 1729-1738页

作者： Klaus w.Lange Andreas Reissm.nn Yukiko Nakam.ra Katharina m.Lange Faculty of Hum.n Sciences University of RegensburgRegensburg 93040Germany Departm.nt of Psychology University of BathBath BA27AYUnited Kingdom

The hypothesis that som. children w.th attention-deficit hyperactivity disorder(ADHD)m.y show.sensitivity or allergic reactions to various food item. has led to the developm.nt of the the few.foods(or oligoantigenic)*** rationale of the diet is to elim.nate certain foods from.the diet in order to exclude potential allergens contained either naturally in food or in artificial ingredients w.th allergenic *** oligoantigenic diet attem.ts to identify individual foods to w.ich a person m.ght be ***,ADHD sym.tom. are m.nitored w.ile m.ltiple foods are excluded from.the ***,if sym.tom. rem.t,foods are re-introduced,w.ile observing the individual for the return of *** advantage of the oligoantigenic diet is that it can be tailored to the individual.A grow.ng body of evidence suggests that behavioral sym.tom. of subgroups of children w.th ADHD m.y benefit from.the elim.nation of certain *** effect sizes of an oligoantigenic diet regarding im.rovem.nt of ADHD sym.tom. have been found to be m.dium.to *** evidence suggests that the investigation of the role of food hypersensitivities in ADHD is a prom.sing avenue w.rthy of further *** large-scale,random.zed controlled studies including assessm.nt of long-term.outcom. are therefore w.rranted.

关键词： Attention-deficit hyperactivity disorder Food intolerance Few.foods diet Etiology Treatm.nt

Prevalence and intensity of urinary schistosom.asis and soil-transm.tted helm.nths am.ng w.m.n of reproductive age in m.alupham.a,Kw.le

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Asian Pacific Journal of Tropical m.dicine 2024年第2期17卷 71-83页

作者： Sam.el m.Ngui Joseph m.m.angangi Joachim.Richter Josephine w.Ngunjiri Departm.nt of Biological Sciences University of EmbuKenya m.dical Entom.logy Kenya Medical Research Institute(KEMRI)Center for Geographic Medicine Research Coast KilifiKenya Institute of International Health Global Health CenterCharitéUniversity MedicineBerlinCorporate Member of Free University and Humboldt University and Berlin Institute of HealthBerlinGermany Sw.ss Tropical and Public Health Institute BaselSwitzerland Tropical and Infectious Diseases Department of Biological sciencesUniversity of EmbuKenya

Objective:To assess the epidem.ology of urinary schistosom.asis and soil-transm.tted helm.nthiasis am.ng w.m.n of reproductive age in m.alupham.a,Kw.le County,***:A com.unity-based cross-sectional study design w.s em.loyed to random.y sam.le 422 w.m.n of reproductive age(15-m.four villages in m.alupham.a *** specim.ns w.re collected and exam.ned using the Kato-Katz m.thod,w.ile filtration technique w.s used to analyze urine ***’sociodem.graphic details w.re obtained using a standardized ***:Urinary schistosom.asis prevalence w.s at 4.7%(20/422,95%CI 2.8%-6.9%)w.ile the prevalence of soil-transm.tted helm.nthiasis infection w.s 4.5%(19/422,95%CI 2.6%-6.7%).The infection intensities of urinary schistosom.asis am.ng the study participants ranged from.1 to 120 eggs/10 m. of urine w.th m.dian egg count of 18.45 eggs/10 *** patients w.re diagnosed w.th light infection,of 56.16 egg/gram.and 48.48 egg/gram.for Trichuris trichiura and hookw.rm.,*** w.thout latrines had 15.7 tim.s higher risk of having urinary schistosom.asis com.ared to those w.th a ***,use of surface w.ter(aOR=1.0,95%CI 0.2-1.4,P=0.010)and crossing the river to go to a place(aOR=1.1,95%CI 0.3-1.6,P=0.009)w.re statistically significant risk factors for getting urinary *** bivariable regression analysis,defecating around the w.ter source(OR=4.3,95%CI 1.5-12.9)had a statistically significant association w.th the prevalence of soil-transm.tted helm.nthiasis(P=0.008).Conclusions:This study has given an insight on the prevalence and intensity of urinary schistosom.asis and soil-transm.tted helm.nthiasis in m.alupham.a location that form.a basis for strengthening the control and elim.nation program.es for these neglected tropical diseases.

关键词： Urinary schistosom.asis Prevalence Soiltransm.tted helm.nths m.alupham.a

HVSR analysis of pum.ce sands for sedim.nt depth characterization:A case study for Guadalajara,m.xico

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 577-591页

作者： Hafid Salgado m. Alejandro Ram.rez-Gaytan Adolfo Preciado Christian R.Escudero Departam.nto de Ciencias Exactas Centro Universitario de la CostaUniversidad de GuadalajaraCP.48280 Puerto VallartaJaliscoMéxico Departam.nto de Ciencias Com.utacionales Centro Universitario de Ciencias Exactas e IngenieríaUniversidad de GuadalajaraCP.44430 GuadalajaraJaliscoMéxico Departam.nto del Hábitat y Desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente(ITESO)CP.45604 TlaquepaqueMéxico

The horizontal to vertical spectral ratio(HVSR)m.thodology is used here to characterize pum.ce soils and to im.ge the three-dim.nsional surface geom.try of Guadalajara,*** to other Latin Am.rican cities,Guadalajara is exposed to high seism.c risk,w.th the particularity of being the largest urban settlem.nt in Latin Am.rica built on pum.ce *** has not yet been tested to characterize subsoil depths in pum.ce *** to the questionable use of traditional geotechnical tests for the analysis of pum.ce soils,HVSR provides an alternative for its characterization w.thout altering its fragile and porous *** this w.rk,resonance frequency(F0)and peak am.litude(A0)are used to constrain the depth of the m.jor im.edance contrast that represents the interface betw.en bedrock and pum.ce *** w.re com.ared w.th borehole depths and other available geotechnical and geophysical data and show.good *** of the profiles estim.ted on the riverbanks that cross the city,reveals different subsoil thickness that could have an im.act on different site responses on riverine areas to an eventual *** and academ.c efforts are com.ined in this w.rk to characterize depth sedim.nts,an im.ortant param.ter that im.acts the regulations for construction in the city.

关键词： subsoil of Guadalajara shallow.soil thickness bedrock depth pum.ce soil characterization

A high Li-ion diffusion kinetics in m.ltidim.nsional and com.act-structured electrodes via vacuum.filtration casting

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Journal of Energy Chem.stry 2024年第6期93卷 368-376,I0010页

作者： Jieqiong Li Ting Ouyang Lu Liu Shu Jiang Yongchao Huang m.-Sadeeq Balogun College of m.terials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan UniversityChangsha 410082HunanChina Institute of Environm.ntal Research at Greater Bay Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006GuangdongChina

m.nufacturing process,diffusion co-efficient and areal capacity are the three m.in criteria for regulating thick electrodes for lithium.ion batteries(LIBs).How.ver,sim.ltaneously regulating these criteria for LIBs is desirable but rem.ins a significant *** this w.rk,niobium.pentoxide(Nb_(2)O_(5))anode and lithium.iron phosphate(LiFePO_(4))cathode m.terials w.re chosen as the m.del m.terials and dem.nstrate that these three param.ters can be sim.ltaneously m.dulated by incorporation of m.cro-carbon fibers(m.F)and carbon nanotubes(CNT)w.th both Nb_(2)O_(5) and LFP via vacuum.filtration *** as-prepared m.C-20 anode and m.C-20 cathode achieves high reversible areal capacity of≈5.4 m.A h cm.(-2)@0.1 C and outstanding Li-ion diffusion coefficients of≈10~(-8)cm.2 s~(-1)in the half-cell *** assem.led m.C-20‖m.C-20 full cell LIB delivers m.xim.m.energy and pow.r densities of244.04 w.h kg^(-1)and 108.86 w.kg^(-1),*** excellent electrochem.cal properties of the asprepared thick electrodes can be attributed to the highly conductive,m.chanical com.actness and m.ltidim.nsional m.tual effects of the m.F,CNT and active m.terials that facilitates rapid Li-ion diffusion ***,electrochem.cal im.edance spectroscopy(EIS),sym.etric cells analysis,and insitu Ram.n techniques clearly validates the enhanced Li-ion diffusion kinetics in the present architecture.

关键词： Thick electrodes Carbon nanotubes Li-ion diffusion co-efficient Vacuum.filtration technique High areal capacity Lithium.ion batteries