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Buechel Pappas r.sur.acing Shoulder.r.placement: Evolution and over.40 Year. of Clinical Exper.ence

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Open j.ur.al of Or.hopedics 2024年第5期14卷 218-228页

作者： frederick F. Buechel Michael j. Pappas r.tger. Nj.Medical School Newark NJ USA South Mountain Or.hopaedic Associates South Orange NJ USA New j.r.ey Institute of Technology Newark NJ USA

Backgr.und: Ear.y explor.tion of the semi constr.ined “Floating-Socket” total shoulder.r.placement (TSr. in 1974 led to a pr.lifer.tion of var.ous unconstr.ined designs that allowed r.section or.r.tention of the humer.l head, depending upon the pathological pr.cess involved. Degener.tive glenohumer.l ar.hr.tis with mild to moder.te involvement of subchondr.l bone allowed for.a r.sur.acing option, while sever. humer.l head involvement r.quir.d a par.ial or.full humer.l head r.placement attached to an intr.medullar. stem for.fixation. All components evolved fr.m cemented to cementless application by 1982. The pur.ose of this paper.is to descr.be the pr.gr.ssion of Buechel-Pappas (B-P) shoulder.r.placement development fr.m the ear.y 1970’s in both cemented and cement less applications. Methods: Clinical evaluations of “Floating-Socket” TSr. followed by B-P stem-type, r.sur.acing types, bipolar.type and r.vision components, all of which compr.se the B-P Shoulder.r.placement System, wer. per.or.ed over.a 49-year.per.od. r.sults: “Floating-Socket” implants impr.ved the r.sults of simple, constr.ined ball-in-socket designs, but gener.lly failed by glenoid component loosening in both chimpanzee and human applications. Unconstr.ined r.sur.acing-type components, both anatomical humer.l head and full pr.ximal humer.l components, wer. quite successful, with minimal failur.s obser.ed in long-ter. studies. Bipolar.salvage implants, used for.sever. pr.ximal deficiencies, r.visions and massive r.tator.cuff ar.hr.pathy, wer. also ver. successful;pr.viding over.ead r.nge of motion in many patients. Conclusions: r.sur.acing hemiar.hr.plasty, in patients with intact or.r.pair.ble r.tator.cuff mechanisms, gave the most satisfactor. r.sults and wer. the least technically complicated to per.or., r.quir.ng minimal instr.mentation. r.sur.acing of full pr.ximal humer.l deficiencies, using femor.l r.sur.acing components, gave similar.clinical r.sults to mor. complex semi-constr.ined devices,

关键词： Total Shoulder.r.placement r.sur.acing Shoulder.r.placement

Fir.t-pr.nciples calculations to investigate str.ctur.l,electr.nic,magnetic,optical and ther.odynamic pr.per.ies of r._(2)r._(3)Ge(r.=Pr.Sm)

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j.ur.al of r.r. Ear.hs 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier.r.Masr.ur.M.Hamedoun j.Khar.ach A.r.zzouk A.Hour.atallah N.Benzakour.K.Bouslykhane Labor.tor. of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper.we analyzed the physical char.cter.stics of the ter.ar. alloys r._(2)r._(3)Ge(r.=Pr.and Sm)using the fir.t pr.nciples calculation based on functional density theor. integr.ted in the Wien2k *** calculated for.ation ener.ies of Pr.(2)r._(3)Ge and Sm_(2)r._(3)Ge ar.−5.3827 and−5.2782 eV/atom,r.spectively,showing that these alloys may exist *** r.sults of the band str.ctur. and density of states indicate that all of the compounds tested ar. magnetic metals,and their.magnetism is mostly r.lated to the contr.bution of Pr.and Sm *** total magnetic moments of Pr.(2)r._(3)Ge and Sm_(2)r._(3)Ge ar. 4.07245 and 11.16161μB/f.u,*** par.meter. such as heat capacity at constant pr.ssur.,entr.py,Debye temper.tur.,lattice volume,compr.ssibility coefficients,and Gr.neisen par.meter.alloys wer. calculated using the Gibbs algor.thm and studied in depth over.a lar.e temper.tur. r.nge of 0-900 *** Debye temper.tur. incr.ases with incr.asing pr.ssur. and decr.ases with decr.asing ***,the Debye temper.tur.s calculated at p=0 GPa and T=300 K ar. equal to be 342 and 322 K for.Pr.(2)r._(3)Ge and Sm_(2)r._(3)Ge,*** optical char.cter.stics such as the r.al and imaginar. por.ions of the dielectr.c function,the absor.tion coefficient,the ener.y-loss function,and the r.fr.ctive index wer. investigated and discussed in mor. depth.

关键词： Magnetic metals Functional density theor. Density of states Magnetic moment Optical and ther.odynamic pr.per.ies r.r. ear.hs

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Fetal Head Compr.ssion: Its Possible r.le in Neur.logic Inj.r.

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Open j.ur.al of Obstetr.cs and Gynecology 2024年第1期14卷 124-143页

作者： Bar.y S. Schifr.n Br.an j. Koos Wayne r. Cohen Depar.ment of Obstetr.cs and Gynecology The Western University of Health Sciences Pomona USA The David Geffen School of Medicine at UCLA Los Angeles USA The Univer.ity of Ar.zona College of Medicine Tucson USA

It is widely assumed that fetal ischemic br.in inj.r. dur.ng labor.der.ves almost exclusively fr.m sever., systemic hypoxemia with mar.ed neonatal depr.ssion and acidemia. Sever. asphyxia, however. is one of sever.l causes of per.natal neur.logical inj.r. and may not be the most common;most neonates diagnosed with hypoxic-ischemic encephalopathy do not have evidence of sever. asphyxia. Sepsis, dir.ct br.in tr.uma, and dr.g or.toxin exposur. account for.some cases, while mechanical for.es of labor.and deliver. that incr.ase fetal intr.cr.nial pr.ssur. sufficiently to impair.br.in per.usion may also contr.bute. Because of bony compliance and mobile sutur. lines, the fetal skull changes shape and r.distr.butes cer.br.spinal fluid dur.ng labor.accor.ing to constr.ints imposed by contr.ctions, and bony and soft tissue elements of the bir.h canal as the head descends. These accommodations, including the incr.ase in intr.cr.nial pr.ssur., ar. adaptive and necessar. for.efficient descent of the head while safeguar.ing cer.br.l blood flow. Autonomic r.flexes mediated thr.ugh centr.l r.ceptor. nor.ally pr.vide ample pr.tection of the br.in fr.m the consider.ble pr.ssur. exer.ed on the skull. On occasion, those for.es, which ar. tr.nsmitted intr.cr.nially, may over.ome the var.ous adaptive anatomical, car.iovascular. metabolic, and neur.logical mechanisms that maintain cer.br.l per.usion and oxygen availability, r.sulting in ischemic br.in inj.r.. Accepting the notion of a potentially adver.e impact of fetal head compr.ssion suggests that avoidance of excessive uter.ne activity and of r.lentless pushing without steady pr.gr.ss in descent may offer.pr.tection for.the fetal br.in dur.ng par.ur.tion. Excessive head compr.ssion should be consider.d in the differ.ntial diagnosis of ischemic encephalopathy.

关键词： Fetal Br.in Inj.r. Fetal Head Compr.ssion Ischemic Encephalopathy Neonatal Encephalopathy

Heat and Mass Tr.nsfer.for.a Nanofluid Flow in Fluidized Bed Dr.er.in Pr.sence of Induced Magnetic Field

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j.ur.al of Applied Mathematics and Physics 2024年第4期12卷 1401-1425页

作者： Kiptum j. Pur.ty Mathew N. Kinyanj.i Edwar. r. Onyango Pan Afr.can Univer.ity Institute for.Basic Sciences Technology and Innovation Nairobi Kenya Depar.ment of Pur. and Applied Mathematics Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya

This r.sear.h entails the study of heat and mass tr.nsfer.of nanofluid flow in a fluidized bed dr.er.used in tea dr.ing pr.cesses in pr.sence of induced magnetic field. A mathematical model descr.bing the fluid flow in a Fluidized bed dr.er.was developed using the nonlinear.par.ial differ.ntial equations. Due to their.non-linear.ty, the equations wer. solved numer.cally by use of the finite differ.nce method. The effects of physical flow par.meter. on velocity, temper.tur., concentr.tion and magnetic induction pr.files wer. studied and r.sults wer. pr.sented gr.phically. Fr.m the mathematical analysis, it was deduced that addition of silver.nanopar.icles into the fluid flow enhanced velocity and temper.tur. pr.files. This led to impr.ved heat tr.nsfer.in the fluidized bed dr.er. hence amplifying the tea dr.ing pr.cess. Fur.her.or., it was noted that induced magnetic field tends to decr.ase the fluid velocity, which r.sults in unifor. distr.bution of heat leading to efficient heat tr.nsfer.between the tea par.icles and the fluid, thus impr.ving the dr.ing pr.cess. The r.sear.h findings pr.vide infor.ation to industr.es on ways to optimize ther.al per.or.ance of fluidized bed dr.er..

关键词： Heat Tr.nsfer Induced Magnetic Field Nanofluid Fluidized Bed Dr.er

Bivar.ate Analysis of Pollutants Monthly Maxima in Mexico City Using Extr.me Value Distr.butions and Copula

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j.ur.al of Envir.nmental Pr.tection 2024年第7期15卷 796-826页

作者： j.an A. Vazquez-Mor.les Eliane r. r.dr.gues Hor.ensia j. r.yes-Cer.antes Facultad de Ciencias Fsico-Matemticas Benemrita Universidad Autnoma de Puebla Puebla Mexico Instituto de Matemticas Universidad Nacional Autnoma de Mxico Mexico City Mexico

In the pr.sent wor., we ar. inter.sted in studying the j.int distr.butions of pair. of the monthly maxima of the pollutants used by the envir.nmental author.ties in Mexico City to classify the air.quality in the metr.politan ar.a. In or.er.to obtain the j.int distr.butions a copula will be consider.d. Since we ar. analyzing the monthly maxima, the extr.me value distr.butions of Weibull and Fr.chet ar. taken into account. Using these two distr.butions as mar.inal distr.butions in the copula a Bayesian infer.nce was made in or.er.to estimate the par.meter. of both distr.butions and also the association par.meter. appear.ng in the copula model. The pollutants taken into account ar. ozone, nitr.gen dioxide, sulphur.dioxide, car.on monoxide, and par.iculate matter.with diameter. smaller.than 10 and 2.5 micr.ns obtained fr.m the Mexico City monitor.ng networ.. The estimation was per.or.ed by taking samples of the par.meter. gener.ted thr.ugh a Mar.ov chain Monte Car.o algor.thm implemented using the softwar. OpenBugs. Once the algor.thm is implemented it is applied to the pair. of pollutants wher. one of the coor.inates of the pair.is ozone and the other.var.es on the set of the r.maining pollutants. Depending on the pollutant and the r.gion wher. they wer. collected, differ.nt r.sults wer. obtained. Hence, in some cases we have that the best model is that wher. we have a Fr.chet distr.bution as the mar.inal distr.bution for.the measur.ments of both pollutants and in other. the most suitable model is the one assuming a Fr.chet for.ozone and a Weibull for.the other.pollutant. r.sults show that, in the pr.sent case, the estimated association par.meter.is a good r.pr.sentation to the cor.elation par.meter. between the pair.of pollutants analyzed. Additionally, it is a str.ightfor.ar. task to obtain these cor.elation par.meter. fr.m the cor.esponding association par.meter..

关键词： Copula Extr.me Value Distr.bution Bayesian Infer.nce Air.Pollution Mexico City

粉末冶金Al-5.6Zn-2Mg合金在热压缩过程中加工硬化特性及本构模型的比较

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j.ur.al of Centr.l South Univer.ity 2024年第2期31卷 346-368页

作者： KATIKA Har.kr.shna DAMODA r.K. DAVIDSON M.j. SEETHAr.M r. KASAGANI Veer. Venkata Nagar.j. Depar.ment of Mechanical Engineer.ng National Institute of TechnologyWarangal 506004India Depar.ment of Mechanical Engineer.ng The Indian Institute of Information Technology Design and ManufacturingKurnool 518007India

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2Mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的... 详细信息

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2Mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的相关性。使用了四个本构模型,Ar.henius模型、改进的j.hnson-Cook模型(Mj.)、改进的Zer.lli-Ar.str.ng模型(MZA)和开发的人工神经网络(ANN)。结果表明,ANN型模型和Ar.henius模型的相对误差的绝对平均值最低,分别为0.486%和3.36%,MZA型模型和Mj.型模型的相对误差的绝对平均值较高,分别为8.84%和3.93%。由于Ar.henius模型能够处理各种因素之间的非线性关系,因此它被认为是最合适的预测模型,但在材料性质未知或实验数据有限的情况下,Mj.模型可能是一种更简单的替代方法。MZA模型不适合估计热压缩时的流变应力。此外,训练最好的神经网络模型的预测性能最好,相对误差的绝对平均值为0.486%,r.为0.99。

关键词：加工硬化速率曲线本构建模热压缩 EBSD分析流变曲线

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Editor.al for.the Special Issue on Emer.ing Technology and Advanced Application of Nondestr.ctive Detection for.Power.Equipment

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Chinese j.ur.al of Electr.cal Engineer.ng 2024年第1期10卷 1-2页

作者： Li j. Mei H. Li S. Tianj.n Univer.ity China Tsinghua Shenzhen Inter.ational Gr.duate School China Lanzhou j.aotong Univer.ity China

The r.pid development of clean and r.newable ener.y technologies r.pr.sented by wind and solar.ener.y,as well as the continuous gr.wth of load demand,have put for.ar. higher.r.quir.ments for.the safe oper.tion of the power.*** per.or.ance of power.equipment based on tr.ditional dielectr.c mater.als is often limited by var.ous defects gener.ted dur.ng molding,tr.nspor.ation,assembly,and oper.tion,which cannot meet the r.liability r.quir.ments of power.systems in the new *** detection is an essential technical method in industr.al development,which can detect and evaluate the defect and damage status of in-ser.ice equipment,key components,and mater.als without damaging the obj.ct.

关键词： ser.ice Application oper.tion

Mathematical modelling of ball and plate system with exper.mental and cor.elation function-based model validation

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Contr.l Theor. and Technology 2024年第2期22卷 326-341页

作者： T.r.Dil Kumar.S.j.Mij. Depar.ment of Electr.cal Engineer.ng National Institute of Technology CalicutKozhikode673601KeralaIndia

The ball and plate system is an inher.ntly nonlinear.under.actuated benchmar. system used for.validating the per.or.ance of var.ous contr.l schemes. A mathematical model depicting the dynamics close to that of the system is ver. much r.quir.d for.such a test bed. In this cor.espondence, the complete nonlinear.model, a simplified nonlinear.model, and a linear.zed model of the ball and plate system ar. developed. The system compr.ses a ball and plate mechanism and a r.tar. ser.o unit. The ball and plate mechanism is modelled using the Euler.Lagr.nge method, wher.as the r.tar. ser.o subsystem is modelled fr.m the fir.t pr.nciples. The nonlinear.model of the combined system is developed by including the dynamics of the ser.o motor.with gear.and r.lling r.sistance between the ball and the plate. The simplified nonlinear.model of the system is obtained with suitable assumptions. The model is linear.zed ar.und the oper.ting point using the j.cobian. The validity of the developed models is investigated thr.ugh cor.elation function analysis. The open-loop r.sponse of the thr.e models, viz., nonlinear. simplified nonlinear. and linear.zed models, is analyzed in the MATLAB/Simulink platfor.. Since the open-loop system is unstable, the exper.mental validation of the model is per.or.ed with a double-loop PSO (par.icle swar. optimization) PID contr.l scheme.

关键词： Ball and plate system Cor.elation function Model validation Par.icle swar. optimization(PSO) PSO PID contr.ller

Dietar. fibr. effects and the inter.lay with exogenous car.ohydr.ses in poultr. nutr.tion

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Animal Nutr.tion 2024年第1期16卷 231-240页

作者： Michael r.Bedfor. Bir.er.Svihus Aar.n j.Cowieson AB Vista Feed Ingr.dients Ltd Nor.egian Univer.ity of Life Sciences DSM Nutr.tional Pr.ducts

A compr.hensive under.tanding of the r.le of dietar. fibr. in non-r.minant animal pr.duction is elusive. Equivocal and conflated definitions of fibr. coupled with significant analytical complexity,inter.ct with poor.y defined host and micr.biome r.lationships. Dietar. fibr. is known to influence gut development, feed intake and passage r.te, nutr.ent absor.tion, micr.biome taxonomy and function, gut p H, endogenous nutr.ent loss, envir.nmental sustainability, animal welfar. and mor.. Whilst significant gaps per.ist in our.under.tanding of fibr. in non-r.minant animal pr.duction, ther. is substantial inter.st in optimizing the fibr. fr.ction of feed to induce high value phenotypes such as impr.ved welfar.,live per.or.ance and to r.duce the envir.nmental footpr.nt of animal pr.duction systems. In or.er.to achieve these aspir.tional goals, it is impor.ant to tackle dietar. fibr. with the same level of scr.tiny as is cur.ently done for.other.cr.tical nutr.ent classes such as pr.tein, miner.ls and vitamins. The chemical,mechanical and nutr.tional r.le of fibr. must be explor.d at the level of monomer.c sugar., oligosacchar.des and polysacchar.des of var.ing molecular.weight and decor.tion, and this must be in par.llel to standar.isation of analytical tools and definitions for.speciation. To fur.her.complicate subj.ct, exogenous car.ohydr.ses r.cognise dietar. fibr. as a focal substr.te and have var.ing capacity to gener.te lower.molecular.weight car.ohydr.tes that inter.ct differ.ntially with the host and the enter.c micr.biome. This shor. r.view ar.icle will explor. the inter.ctive space between dietar. fibr. and exogenous car.ohydr.ses and will include their.nutr.tional and health effects with emphasis on functional development of the gut, micr.biome modulation and host metabolism.

关键词： Fibr. Car.ohydr.se Nutr.tion Micr.biome Gastr.-intestinal development Feed