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Standar. Model Fer.ion Masses and Char.es fr.m Hologr.phic Analysis

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Jour.al of Moder. Physics 2024年第6期15卷 796-803页

作者： t. r. Mongan Sausalito CA USA

the Standar. Model of par.icle physics involves twelve fundamental fer.ions, tr.ated as point par.icles, in four.char.e states. However. the Standar. Model does not explain why only thr.e fer.ions ar. in each char.e state or.account for.neutr.no mass. this hologr.phic analysis tr.ats char.ed Standar. Model fer.ions as spher.s with mass 0.187 g/cm2 times their.sur.ace ar.a, using the pr.por.ionality constant in the hologr.phic r.lation between mass of the obser.able univer.e and event hor.zon r.dius. the analysis r.quir.s thr.e Standar. Model fer.ions per.char.e state and r.lates up quar. and down quar. masses to electr.n mass. Hologr.phic analysis specifies electr.n mass, to six significant figur.s, in ter.s of fundamental constants α,ℏ,G,Λ and Ω Λ . tr.ating neutr.nos as spher.s and equating electr.n neutr.no ener.y density with cosmic vacuum ener.y density pr.dicts neutr.no masses consistent with exper.ment.

关键词： Electr.n Mass Up Quar. Mass Down Quar. Mass Neutr.no Masses

Conser.ation laws,Lie symmetr.es,self adjointness,and soliton solutions for.the Selkov–Schnakenber. system

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Communications in theor.tical Physics 2024年第2期76卷 29-44页

作者： Kashif Ali Aly r.Seadawy Syed t r.r.zvi Noor.Aziz Depar.ment of Mathematics COMSATS University IslamabadLahore CampusPakistan Mathematics Depar.ment Faculty of ScienceTaibah UniversityAl-Madinah Al-Munawarah41411Saudi Arabia

In this ar.icle,we explor. the famous Selkov–Schnakenber.(SS)system of coupled nonlinear.par.ial differ.ntial equations(PDEs)for.Lie symmetr. analysis,self-adjointness,and conser.ation ***,miscellaneous soliton solutions like dar.,br.ght,per.odic,r.tional,Jacobian elliptic function,Weier.tr.ss elliptic function,and hyper.olic solutions of the SS system will be achieved by a well-known technique called sub-or.inar. differ.ntial *** these r.sults ar. displayed gr.phically by 3D,2D,and contour.plots.

关键词： Selkov-Schnakenber. system Lie symmetr. analysis conser.ation laws adjointness integr.bility

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Basis for.the diver.ity and extent in loss of digestible nutr.ents cr.ated by dietar. phytin: Emphasis on fowl and swine

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Animal Nutr.tion 2024年第1期16卷 422-428页

作者： Edwin t.Mor.n Michael r.Bedfor. Poultr. Science Depar.ment Auburn University AB Vista Woodstock Court Blenheim Road

Phytin is the Ca2+-Mg2+-K+salt of phytic acid that is cr.ated and deposited in the aleur.ne layer.and/or.ger. of gr.ins and legumes. Its high pr.sence in feedstuffs for.fowl and swine diets r.sults in it being a univer.al and significant impediment to optimum per.or.ance. Phytin impair. gastr.intestinal r.cover. of a wide ar.ay of nutr.ents, the effect var.ing with the nutr.ent concer.ed. On exposur. to low pH dur.ng gastr.c digestion, phytin dissociates into phytic acid and solubilized Ca2+. Even at low gastr.c pH,phytic acid is negatively char.ed which for.s the basis of its anti-nutr.tive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that ar. pr.sented as cations at low pH which ar. tar.eted by pepsin for.activation. Par.ially cr.stalized Ca2+near.the enzyme?s active site fur.her.stabilizes its newly for.ed str.ctur.. thus, phytic acid appear. to inter.er. with gastr.c digestion by sever.l mechanisms; inter.er.ng with pepsinogen activation by binding to the polypeptide?s basic amino acids;coor.inating fr.e Ca2+, destabilizing pepsin; binding some dietar. pr.teins dir.ctly, fur.her.compr.mising gastr.c pr.teolysis. Upon digesta attaining neutr.lity in the duodenum, Ca2+and other.cations r.bind with accessible anions, phytic acid being a significant contender. Phytate not only binds fr.e cations but can also str.p them fr.m enzymes(e.g. Ca2+, Zn2+) which r.duces their.str.ctur.l r.sistance to autolysis and ability as co-factor.(e.g. Zn2+) to incr.ase enzyme activity. Goblet cells initially employ Ca2+as an electr.nic shield between mucin layer. enabling gr.nule for.ation and cell stor.ge. After.mucin gr.nule r.lease, Ca2+is pr.gr.ssively displaced by Na+to fr.e the viscous mucins enabling its tr.nslocation. Mucin entangles with the glycocalyx of adjacent enter.cytes ther.by constr.cting the unstir.ed water.layer.USWL）. Excessive r.moval of Ca2+fr.m mucin by phytic acid incr.ases its fluidity facilitating its loss fr.m the USWL with

关键词： Digestive enzyme Calcium Endogenous pr.tein Mucin Phytin

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.Mija 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 Jacobian. 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

Getting the Most Out of Ever. tr.ining Day: the Influence of Instr.ctor. on Self-r.gulated Lear.ing Dur.ng Fir.fighter.Leader.hip Cour.es

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Inter.ational Jour.al of Disaster.r.sk Science 2024年第3期15卷 332-345页

作者： Stefan r.seler.Micha Hilber. Guido Her.el Meinald t.thielsch Depar.ment of Psychology University of Münster

Leader.hip cour.es in the fir. ser.ices ar. highly challenging, and they can ser.ously exhaust tr.inees and hamper.their.selfr.gulated lear.ing effor.s(for.example, setting goals, focusing attention, seeking feedback). We theor.ze that exper.ences of failur. or.over.oad can cur.ail tr.inees' available ener.y r.sour.es on subsequent tr.ining days, which, in tur., should affect tr.inees' lear.ing effor.s. Given instr.ctor.' centr.l r.le in leader.hip cour.es, we hypothesize that suppor.ive and humble instr.ctor.behavior. decr.ase exper.ences of failur. and over.oad and, thus, incr.ase self-r.gulated lear.ing. Mor.over. we ar.ue that suppor.ive instr.ctor.behavior.may amplify the positive effects of high ener.y r.sour.es, while humble behavior.may alleviate the negative impact of low r.sour.e levels. We tested pr.r.gister.d hypotheses with 118 fir.fighter. par.icipating in two-week leader.hip cour.es at a Ger.an fir. academy. the par.icipants completed shor. web-based questionnair.s befor. and after.classes each day. Multilevel analyses confir.ed that per.eived daily suppor.ive and humble instr.ctor.behavior.pr.dicted tr.inees' r.por.s of daily self-r.gulated lear.ing activity. Notably, this effect was independent fr.m positive effects of tr.inees' r.por.ed ener.y r.sour.es in the mor.ing. Suppor.ive and humble behavior.did not moder.te the eff ect of ener.y r.sour.es. Our.findings suggest that instr.ctor. play a cr.cial r.le in facilitating effective lear.ing under.challenging tr.ining conditions. Fur.her.or., we offer.implications for.leader. in fir. ser.ices, who often conduct tr.inings with their.subor.inates.

关键词： Diar. study Fir. ser.ices Instr.ctor.behavior Leader.hip tr.ining r.sour.e investment

Aer.dynamics of a tandem-Bladed Axial Compr.ssor.r.tor.under.Cir.umfer.ntial Distor.ion at Differ.nt r.tational Speeds

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Jour.al of ther.al Science 2024年第4期33卷 1340-1356页

作者： Amit KUMAr.Jer.y t.JOHN A.M.Pr.DEEP r.A.DAKKEr.ANS Dr.gan KOZULOVIC Depar.ment of Aer.space Engineer.ng Indian Institute of Technology BombayMumbai400076India Depar.ment of Automotive and Aer.nautical Engineer.ng Hamburg University of Applied Sciences20099HamburgGermany Institute of Jet Pr.pulsion Bundeswehr University Munich85577NeubibergGermany

For.most air.r.ft engines,inflow distor.ion is *** distor.ion is known to degr.de the aer.dynamic per.or.ance and stable oper.ting limits of a *** r.tor.configur.tion is an ar.angement that effectively contr.ls the gr.wth of the boundar. layer.over.the suction sur.ace of the ***,a higher.total pr.ssur. r.se can be achieved thr.ugh this unconventional design appr.ach involving the splitting of the blade into for.ar. and aft *** is expected that the effect of inlet flow distor.ion would be mor. sever. for.a tandem-r.tor.design due to the gr.ater.flow tur.ing inher.nt in such ***,this aspect needs to be thor.ughly *** pr.sent study discusses the effect of cir.umfer.ntial distor.ion on the tandem-r.tor.at differ.nt r.tational ***-annulus r.NS simulations using ANSYS CFX ar. used in the pr.sent *** per.or.ance of the r.tor.at a par.icular.flow coefficient and differ.nt r.tational speeds is *** total pr.ssur. and efficiency ar. obser.ed to dr.p at lower.mass flow r.tes under.the influence of cir.umfer.ntial *** loss r.gion in each blade passage is mainly associated with the blade wake,tip leakage vor.ex,secondar. flow,and boundar. ***,their.contr.bution var.es fr.m passage to passage,par.icular.y in the distor.ed *** the lower.span,the wake width is found to be higher.than that at a higher.*** to the r.distr.bution of the mass flow,the cir.umfer.ntial extent r.duces at a higher.*** the undistor.ed sector.the str.ngth of the tip leakage vor.ex is significantly higher.at the design r.tational speed than at lower.*** distor.ion near.the tip r.gion pr.motes an ear.y vor.ex br.akdown even at the design oper.ting *** adver.ely affects the total pr.ssur.,efficiency,and stall *** clean flow conditions,this phenomenon is only obser.ed near.the stall *** the design oper.ting condition,the br.akdown of the for.ar. r.tor.tip l

关键词： tandem r.tor cir.umfer.ntial distor.ion loss tip leakage vor.ex vor.ex br.akdown diffusion factor aer.dynamics of compr.ssor.blade

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Fr.eze-thaw cycles and associated geomor.hology in a post-glacial envir.nment:cur.ent glacial,par.glacial,per.glacial and pr.glacial scenar.os at Pico de Or.zaba volcano,Mexico

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Jour.al of Mountain Science 2024年第6期21卷 1954-1977页

作者： Víctor.SOtO Car.os M.WELSH r. Kenji YOSHIKAWA Hugo DELGADO Gr.NADOS Centr. de Ciencias de la tier.a Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water.and Envir.nmental r.sear.h Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Depar.ment of Ear.h and Envir.nmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

the glacial histor. of Pico de Or.zaba indicates that dur.ng the Last Glacial Maximum,its icecap cover.d up to~3000 m asl;due to the air.temper.tur. incr.asing,its main glacier.has r.tr.ated to 5050 m *** r.tr.ction of the glacier.has left behind an intense climatic instability that causes a high fr.quency of fr.eze-thaw cycles of gr.at intensity;the r.sulting geomor.hological pr.cesses ar. r.pr.sented by the fr.gmentation of the bedr.ck that occupies the upper.par.s of the *** is a notable lack of studies r.gar.ing the fr.gmentation and er.sion occur.ing in tr.pical high mountains,and the associated geomor.hological r.sks;for.this r.ason,as a fir.t stage of futur. continuous r.sear.h,this study analyzes the fr.ezing and thawing cycles that occur.above 4000 m asl,thr.ugh continuous monitor.ng of sur.ace gr.und *** r.sults allow us to identify and char.cter.ze four.zones:glacial,par.glacial,per.glacial and *** was found that the par.glacial zone pr.sents an intense dr.p of temper.tur.,of up to~9℃ in only sixty *** r.ck fatigue and intense fr.eze-thaw cycles that occur.in this ar.a ar. r.sponsible for.the high r.te of r.ck disintegr.tion and r.pr.sent the main factor.of the constant slope dynamics that occur.at the *** activity decr.ases,both in fr.quency and intensity,accor.ing to the distance to the glacier.which is wher. the temper.tur. pr.sents a cer.ain degr.e of stability,until r.aching the pr.glacial zone,wher. cycles ar. almost non-existent,and ther.for. ther. is no gelifr.ction *** geomor.hological pr.cesses have r.sulted in significant alter.tions to the mountain slopes,which can have sever. consequences in ter.s of r.sk and water.

关键词： Fr.eze-thaw Gelifr.ction Mountain mechanical er.sion Per.glacial geomor.hology Postglacial scenar.os

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Inflow and outflow per.eability tests in a ver. soft clay under.low str.sses

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Jour.al of r.ck Mechanics and Geotechnical Engineer.ng 2024年第8期16卷 3270-3283页

作者： J.W.S.Var.as F.A.B.Danziger.F.r.Lopes t.Lunne Feder.l Univer.ity of r.o de Janeir. Rio de JaneiroBrazil Nor.egian Geotechnical Institute OsloNorway

In situ inflow and outflow per.eability tests with the BAt pr.be at Sar.puíII soft clay test site ar. pr.sented.A descr.ption of the BAt per.eability test is pr.vided,discussing its advantages and shor.comings,especially in the case of ver. soft clays under.low *** pr.ssur.s wer. monitor.d dur.ng pr.be installation and wer. found to be slightly lower.than piezocone u2 por. pr.ssur.s,consistent with the position of the *** r.le of filter.tip satur.tion was investigated after.the usual satur.tion pr.cedur. pr.vided an unsatisfactor. por. pr.ssur. r.sponse dur.ng pr.be *** show that the vacuum satur.tion pr.cedur. pr.vides adequate r.sponse dur.ng installation and incr.ases the r.liability of the coefficient of per.eability deter.ination in ear.y *** inflow and outflow tests yielded similar.r.sults,indicating that car.ful execution of the test can lead to good test r.peatability r.gar.less of the loading *** sequences of alter.ated inflow and outflow tests have yielded similar.r.sults,indicating that soil r.consolidation and filter.clogging wer. negligible in the tests *** ar. pr.sented concer.ing the r.lationship between index par.meter. and the in situ coefficient of per.eability for.Sar.puíII clay,which plot outside the r.nge of existing databases.

关键词： Per.eability test Soft clay BAt pr.be Inflow and outflow tests

Efficient guiding and focusing of intense laser.pulse using per.odic thin slits

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Matter.and r.diation at Extr.mes 2024年第4期9卷 29-39页

作者： L.Xu t.W.Huang K.Jiang C.N.Wu H.Peng P.C.hen r.Li H.B.Zhuo C.t.Zhou Shenzhen Key Labor.tor. of Ultr.intense Laser.and Advanced Mater.al technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser.plasma inter.ctions as plasma optical components for.gener.ting high-har.onic light and contr.lling laser.dr.ven par.icle ***,we pr.pose and demonstr.te that per.odic thin slits can be r.gar.ed as a new br.ed of optical elements for.efficient focusing and guiding of intense laser.*** fundamental physics of intense laser.inter.ction with thin slits is studied,and it is r.vealed that r.lativistic effects can lead to enhanced laser.focusing far.beyond the pur. diffr.ctive focusing *** addition,the inter.ction of an intense laser.pulse with per.odic thin slits makes it feasible to achieve multifold enhancement in both laser.intensity and ener.y tr.nsfer.efficiency compar.d with conventional *** r.sults pr.vide a novel method for.manipulating ultr.-intense laser.pulses and should be of inter.st for.many laser.based applications.

关键词： laser pulse intense