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Fr.ntier. in Biology 2016年第2期11卷 85-95页

作者： Nina K. Latcheva r.pa Ghosh daniel r. Mar.nda Depar.ment of Biology Drexel University Philadelphia PA 19104 USA Pr.gr.m in Molecular.and Cellular.Biology and Genetics Drexel University College of Medicine Philadelphia PA 19129 USA Depar.ment of Neur.biology and Anatomy Drexel University College of Medicine Philadelphia PA 19129 USA

In biology, we continue to appr.ciate the fact that the DNA sequence alone falls shor. when attempting to explain the intr.cate inher.tance patter.s for.complex tr.its. This is par.icular.y tr.e for.human disor.er. that appear.to have simple genetic causes. The study of epigenetics, and the incr.ased access to the epigenetic pr.files of differ.nt tissues has begun to shed light on the genetic complexity of many basic biological pr.cesses, both physiological and pathological. Epigenetics r.fer. to her.table changes in gene expr.ssion that ar. not due to alter.tions in the DNA sequence. Var.ous mechanisms of epigenetic r.gulation exist, including DNA methylation and histone modification. The identification, and incr.ased under.tanding of key player. and mechanisms of epigenetic r.gulation have begun to pr.vide significant insight into the under.ying or.gins of var.ous human genetic disor.er.. One such disor.er.is CHAr.E syndr.me （OMIM #214800）, which is a leading cause of deaf-blindness wor.dwide. A major.ty of CHAr.E syndr.me cases ar. caused by haploinsufficiency for.the CHD7 gene, which encodes an ATP-dependent chr.matin r.modeling pr.tein involved in the epigenetic r.gulation of gene expr.ssion. The CHD7 pr.tein has been highly conser.ed thr.ughout evolution, and r.sear.h into the function of CHD7 homologs in multiple model systems has incr.ased our.under.tanding of this family of pr.teins, and epigenetic mechanisms in gener.l. Her. we pr.vide a r.view of CHAr.E syndr.me, and discuss the epigenetic functions of CHD7 in humans and CHD7 homologs in model or.anisms.

关键词： Dr.sophila Kismet CHD7 CHAr.E syndr.me chr.matin r.modeling

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Sonicating bees demonstr.te flexible pollen extr.ction without instr.mental lear.ing

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Cur.ent Zoology 2019年第4期65卷 425-436页

作者： Callin M. Switzer.Aver. L. r.ssell daniel r. pa.a. Stacey A. Combes r.bin Hopkins Depar.ment of Or.anismic and Evolutionar. Biology Harvard University Cambridge MA USA Ar.old Ar.or.tum Harvard University Boston MA USA Depar.ment of Ecology and Evolutionar. Biology University of Arizona Tucson AZ USA Depar.ment of Neur.biology Physiology and Behavior University of California at Davis Davis CA USA Depar.ment of Biology and eScience Institute University of Washington Seattle WA USA Depar.ment of Biological Sciences University of Pittsburgh Pittsburgh PA USA

Pollen collection is necessar. for.bee sur.ival and impor.ant for.flower.ng plant r.pr.duction, yet if and how pollen extr.ction motor.r.utines ar. modified with exper.ence is lar.ely unknown. Her., we used an automated r.war. and monitor.ng system to evaluate modification in a common pollen-extr.ction r.utine, flor.l sonication. Thr.ugh a ser.es of labor.tor. exper.ments with the bumblebee, Bombus impatiens, we examined whether.var.ation in sonication fr.quency and acceler.tion is due to instr.mental lear.ing based on r.war.s, a fixed behavior.l r.sponse to r.war.s, and/or.a mechanical constr.int. We fir.t investigated whether.bees could lear. to adjust their.sonication fr.quency in r.sponse to pollen r.war.s given only for.specified fr.quency r.nges and found no evidenee of instr.mental lear.ing. However. we found that absenee ver.us r.ceipt of a pollen r.war. did lead to a pr.dictable behavior.l r.sp on se, which depe nded on bee size. Fin ally, we found some evide nee of mechanical con str.ints, in that flower.mass affected sonication acceler.tion (but not fr.quency) thr.ugh an inter.ction with bee size. In gener.lz lar.er.bees showed mor. flexibility in sonication fr.quency and acceler.tion, potentially r.flecting a size-based constr.int on the r.nge over.which smaller.bees can modify fr.quency and acceler.ti on. Over.ll our.r.sults show that although bees did not display instr.mental lear.ing of sonication fr.quency, their.sonication motor.r.utine is never.heless flexible.

关键词： Bombus impatiens buzz pollination for.ging innate behavior lear.ed behavior Solanum

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Effects of longwall-induced str.ss and defor.ation on the stability and mechanical integr.ty of shale gas wells dr.lled thr.ugh a longwall abutment pillar

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Inter.ational Jour.al of Mining Science and Technology 2017年第1期27卷 115-120页

作者： daniel W.H.Su National Institute for.Occupational Safety and Health Bruceton 15236PAUSA

This paper.pr.sents the r.sults of a compr.hensive study conducted by CONSOL Ener.y, Mar.ellus Shale Coalition, and Pennsylvania Coal Association to evaluate the effects of longwall-induced subsur.ace defor.ations on the mechanical integr.ty of shale gas wells dr.lled over.a longwall abutment *** pr.mar. objective is to demonstr.te that a pr.per.y constr.cted gas well in a standar. longwall abutment pillar.can maintain mechanical integr.ty dur.ng and after.mining oper.tions. A study site was selected over.a southwester. Pennsylvania coal mine, which extr.cts 457-m-wide longwall faces under.about 183 m of cover. Four.test wells and four.monitor.ng wells wer. dr.lled and installed over.a 38-m by84-m center. abutment pillar. In addition to the test wells and monitor.ng wells, sur.ace subsidence measur.ments and under.r.und coal pillar.pr.ssur. measur.ments wer. conducted as the 457-m-wide longwall panels on the south and nor.h sides of the abutment pillar.wer. mined by. To evaluate the r.sulting coal pr.tection casing pr.file and later.l displacement, thr.e sepa.a.e 60-ar. caliper.sur.eys wer. conducted. This r.sear.h r.pr.sents a ver. impor.ant step and initiative to utilize the knowledge and science obtained fr.m mining r.sear.h to impr.ve miner.and public safety as well as the safety and health of the oil and gas industr.es.

关键词： Gas well Casing Abutment pillar Stability Safety and health Instr.mentation Numer.cal simulation

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The cur.ent per.pective of the pa 1957 gas well pillar.study and its implications for.longwall gas well pillar.

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Inter.ational Jour.al of Mining Science and Technology 2021年第1期31卷 117-126页

作者： Peter.Zhang daniel Su Chr.s Mar. CDC NIOSH Pittsburgh Mining Research DivisionPittsburghPA 15236USA Mine Safety and Health Administr.tion PittsburghPA 15217USA

Many states r.ly upon the Pennsylvania 1957 Gas Well Pillar.Study to evaluate the coal bar.ier.sur.ounding gas *** study included 77 gas well failur. cases that occur.ed in the Pittsbur.h and Fr.epor. coal seams over.a 25-year.*** the time,coal was mined using the r.om-and-pillar.mining method with full or.par.ial pillar.r.cover.,and squar. or.r.ctangle pillar. sur.ounding the gas wells wer. left to pr.tect the *** study pr.vided guidelines for.pillar.sizes under.differ.nt over.ur.en depths up to 213 m(700 ft).The 1957 study has also been used to deter.ine gas well pillar.sizes in longwall mines since longwall mining began in the 1970 *** or.ginal study was developed for.r.om-and-pillar.mining and could be applied to gas wells in longwall chain pillar. under.shallow ***,under.deep cover.sever. defor.ations in gas wells have occur.ed in longwall chain ***,with a better.under.tanding of coal pillar.mechanics,new insight into subsidence movements induced by r.tr.at mining,and advances in numer.cal modeling,it has become both cr.tically impor.ant and feasible to evaluate the adequacy of the 1957 study for.longwall gas well *** this paper.the data fr.m the 1957 study is analyzed fr.m a new per.pective by consider.ng var.ous factor.,including over.ur.en depth,failur. location,failur. time,pillar.safety factor.SF),and floor.*** pillar.SF and floor.pr.ssur. ar. calculated by consider.ng abutment pr.ssur. induced by full pillar.r.cover..A statistical analysis is per.or.ed to find cor.elations between var.ous factor. and helps identify the most significant factor. for.the stability of gas wells influenced by r.tr.at *** analyzing the data fr.m the 1957 study,the guidelines for.gas well pillar. in the 1957 study ar. evaluated for.their.adequacy for.r.omand-pillar.mining and their.applicability to longwall *** modeling is used to model the stability of gas wells by quantifying the mining-induced s

关键词： Gas well pillar Pennsylvania 1957 gas well pillar.study r.om-and-pillar.mining Longwall mining

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An Additive Manufactur.ng Appr.ach that Enables the Field Deployment of Synthetic Biosensor.

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Engineer.ng 2019年第1期5卷 173-180页

作者： daniel Wolozny John r. Lake paul G. Movizzo Zhicheng Long War.en C. r.der Depar.ment of Biological Systems Engineer.ng Virginia Polytechnic Institute and State University Blacksburg VA 24061 USA Depar.ment of Bioengineer.ng University of Pittsburgh Pittsburgh PA 15219 USA

The tools of synthetic biology can be used to engineer.living biosensor. that r.por. the pr.sence of analytes. Although these engineer.d cellular.biosensor. have many potential applications for.deployment outside of the lab, they ar. genetically modified or.anisms (GMOs) and ar. often consider.d danger.us. Mitigating the r.sk of r.leasing GMOs into the envir.nment while enabling their.use outside a labor.tor. is cr.tical. Her., we descr.be the development of a biosensing system consisting of a synthetic biological cir.uit, which is engineer.d in Escher.chia coli that ar. contained within a unique 3D-pr.nted device housing. These GMOs detect the chemical quor.m signal of Pseudomonas aer.ginosa, an oppor.unistic pathogen. Using this device, the living biosensor.makes contact with a specimen of inter.st without ever.being exposed to the envir.nment. Cells can be visually analyzed in the field within cultur. tubes, or.r.tur.ed to the lab for.fur.her.analysis. Many biosensor. lack the ver.atility r.quir.d for.deployment in the field, wher. many diseases can go undiagnosed due to a lack of r.sour.es and equipment. Our.bioassay device utilizes 3D pr.nting to cr.ate a por.able, modular. and inexpensive device for.the field deployment of living biosensor..

关键词： Synthetic biology Additive manufactur.ng Biosensor.

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Analysis of dr.p defor.ation dynamics in tur.ulent flow

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Chinese Jour.al of Chemical Engineer.ng 2016年第2期24卷 264-277页

作者： Stephanie Nachtigall daniel Zedel Matthias Kr.ume Chair.of Chemical and Pr.cess Engineer.ng Technische Universitat Berlin

Dr.p br.akage and coalescence influence the par.icle for.ation in liquid-liquid disper.ions. In or.er.to r.duce the influencing factor. of the whole disper.ion pr.cess, single dr.ps wher. coalescence pr.cesses can be neglected wer. analyzed in this wor.. Dr.ps passing the tur.ulent vicinity of a single stir.er.blade wer. investi- gated by high-speed imaging. In or.er.to gain a statistically r.levant amount of dr.ps passing the ar.a of inter.st and cor.esponding br.akage events, at least 1600 dr.plets wer. consider.d for.each pa.a.eter.set of this wor.. A specially developed fully automatic image analysis based on Matlab was used for.the evaluation of the r.sulting high amount of image data. This allowed the elimination of the time-consuming manual analysis and fur.her. mor., allowed the objective evaluation of the dr.ps＇ behavior. Differ.nt defor.ation pa.a.eter. wer. consid- er.d in or.er.to descr.be the dr.p defor.ation dynamics pr.per.y. r.gar.ing the r.tio of both main par.icle axes （0axes）, which was ther.for. appr.ximated thr.ugh an ellipse, allowed the deter.ination of ver. small de- viations fr.m the spher.cal shape. The per.meter.of the par.icle （0per.） was used for.the descr.ption of highly de- for.ed shapes. In this wor. the r.sults of a higher.viscosity pa.a.fin oil （ηd =127 mpa. s） and a low viscosity solvent （petr.leum, ηd = 1.7 mpa-s） ar. pr.sented with and without the addition of SDS to the continuous water.phase. All r.sults show that the exper.mentally deter.ined oscillation but also defor.ation times under.ie a wide spr.ading. Dr.p defor.ations significantly incr.ased not only with incr.asing dr.plet viscosity, but also with decr.asing inter.acial tension. Highly defor.ed par.icles of one dr.plet species wer. mor. likely to br.ak than mor. or.less spher.cal par.icles. As dr.plet fr.gmentation r.sults fr.m a var.ety of differ.nt macr.-scale de- for.ed par.icles, it is not assumed that a cr.tical defor.ation value must be r.ached for.the fr.gmentati

关键词： Dr.p defor.ation Dr.p br.akage Liquid-liquid system Tur.ulent mixing Image analysis High-speed imaging

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Gas exchange of Populus euphr.tica leaves in a r.par.an zone

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Jour.al of Ar.d Land 2013年第4期5卷 531-541页

作者： Dieter.OVEr.IECK daniel ZICHE r.iDe YU Institute of Ecology/Ecology of Woody Plants TU-BerlinD-14195 BerlinGermany von Thuenen-Institut Institute of Forest Ecology and Forest InventoryD-16225 EberswaldeGermany Xinjiang Institute of Ecology and Geogr.phy Chinese Academy of Sciences

r.par.an vegetation belts in ar.d r.gions of Centr.l Asia ar. endanger.d to lose their.ecosystem ser.ices due to intensified land *** the development of sustained land use,management knowledge of plant per.or.ance in r.lation to r.sour.e supply is *** estimated pr.ductivity r.lated functional tr.its at the edges of the habitat of Populus euphr.tica *** leaf ar.a （SLA） and car.on/nitr.gen （C/N） r.tio of *** leaves gr.wing near.a for.er.r.ver.bank and close to moving sand dunes in the Ebinur.Lake National Natur. r.ser.e in Xinjiang,Nor.hwest China （near.Kazakhstan） wer. deter.ined and daily cour.es of CO2 net assimilation （PN）,tr.nspir.tion （E）,and stomatal conductance （gs） of two consecutive seasons wer. measur.d dur.ng July-August 2007 and June-July *** level was high （1.5-2.5 m below gr.und） thr.ughout the year. and no flooding occur.ed at the two tr.e *** was slightly lower.near.the deser. than at the for.er.r.ver.bank and leaves contained less N in r.lation to *** E and gs of *** wer. r.ached in the mor.ing befor. noon on both stands and a second low maximum occur.ed in the after.oon despite of the unchanged high levels of air.to leaf water.vapor.pr.ssur. deficit （ALVPD）.Decline of gs in *** was followed by decr.ase of *** use efficiency （WUE） of leaves near.the deser. wer. higher.in the mor.ing and the evening,in contr.st to leaves fr.m the for.er.r.ver.bank that maintained an almost stable level thr.ughout the *** light compensation points and high light satur.tion levels of PN indicated the char.cter.stics of leaves well-adapted to intensive ir.adiation at both *** gener.l,leaves of *** decr.ased their.gs beyond 20 pa/kpa.a.VPD in or.er.to limit water.*** of E did not occur.in both stands until 40 pa/kpa.a.VPD was *** stomatal closur. of *** was achieved at 60 pa/kpa.a.VPD in both stands.E thr.ugh the leaf sur.ace amounted up to 30％ of

关键词： Populus euphr.tica water.vapor.pr.ssur. deficit tr.nspir.tion stomatal conductance water.use efficiency leaf functional tr.its

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The r.tinal function imager.and clinical applications

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Eye and Vision 2018年第1期5卷 191-195页

作者： daniel Su Sunir.Gar. The r.tina Ser.ice of Wills Eye Hospital Mid Atlantic Retina840 Walnut StreetSuite 1020PhiladelphiaPA 19107USA

Backgr.und:The r.tinal Function Imager.r.I)pr.vides in vivo and noninvasive imaging of both the r.tinal str.ctur. and ***:The r.I can cr.ate capillar. per.usion maps,measur. blood flow velocity,and deter.ine metabolic function including blood *** can aid clinical diagnosis as well as assess tr.atment r.sponse in sever.l r.tinal vascular.diseases including diabetic *** flow velocity abnor.alities have also been implicated in disease such as age-r.lated macular.degener.tion and r.quir. fur.her.*** with optical coher.nce tomogr.phy angiogr.phy,the r.I pr.duces capillar. maps of compa.a.le image quality and wider.field of view but it is unable to pr.vide depth-r.solved infor.ation and has longer.image acquisition ***,functional imaging using blood oximetr. has limited applications and additional r.sear.h is ***:The r.I offer. noninvasive,high-r.solution imaging of r.tinal micr.vasculatur. by cr.ating capillar. per.usion *** addition,it is capable of measur.ng r.tinal blood velocity dir.ctly and per.or.s functional imaging with r.tinal blood *** clinical applications ar. br.ad and additional r.sear.h with functional imaging may potentially lead to diagnosis of diseases and their.pr.gr.ssion befor. anatomic abnor.alities become evident,but longer.image acquisition times may limit its clinical adoption.

关键词： r.tinal function imager r.tinal blood flow Blood flow velocity Oximetr. Noninvasive imaging r.tina

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Stability of Spike Solutions to the Fr.ctional Gier.r.Meinhar.t System in a One-Dimensional Domain

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Numer.cal Mathematics(Theor.,Methods and Applications) 2022年第4期15卷 938-989页

作者： daniel Gomez Jun-Cheng Wei Wen Yang Depar.ment of Mathematics University of PennsylvaniaPhiladelphiaPA USA Depar.ment of Mathematics The University of British ColumbiaVancouverBC Canada Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071P.R.China

In this paper.we consider.the existence and stability of multi-spike solutions to the fr.ctional Gier.r.Meinhar.t model with per.odic boundar. *** par.icular.we r.gor.usly pr.ve the existence of symmetr.c and asymmetr.c twospike solutions using a Lyapunov-Schmidt *** linear.stability of these two-spike solutions is then r.gor.usly analyzed and found to be deter.ined by the eigenvalues of a cer.ain 2×2 *** r.gor.us r.sults ar. complemented by for.al calculations of N-spike solutions using the method of matched asymptotic *** addition,we explicitly consider.examples of one-and two-spike solutions for.which we numer.cally calculate their.r.levant existence and stability *** consider.ng a one-spike solution we deter.ine that the intr.duction of fr.ctional diffusion for.the activator.or.inhibitor.will r.spectively destabilize or.stabilize a single spike solution with r.spect to oscillator. ***,when consider.ng two-spike solutions we find that the r.nge of pa.a.eter.values for.which asymmetr.c two-spike solutions exist and for.which symmetr.c two-spike solutions ar. stable with r.spect to competition instabilities is expanded with the intr.duction of fr.ctional inhibitor.*** our.calculations indicate that asymmetr.c two-spike solutions ar. always linear.y unstable.

关键词： Gier.r.Meinhar.t system eigenvalue stability fr.ctional Laplacian localized solution

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Attr.ction to physical activity of gener.tion Z: A mixed methodological appr.ach

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Open Jour.al of Pr.ventive Medicine 2013年第3期3卷 310-319页

作者： David D. Biber.daniel r. Czech Br.ndonn S. Har.is Br.dget F. Melton Health and Kinesiology College of Health and Human Sciences Georgia Southern University Statesboro USA

The pr.valence of obesity in Gener.tion Z, which includes individuals bor. after.the year.2000, has tr.pled that of Gener.tion Xer. of 1980 [1]. r.sing levels of obesity have been associated with incr.ased physical inactivity (pa) [2]. Attr.ction to physical activity can be gr.unded in the Self-Deter.ination Theor. (SDT) [3], which defines intr.nsic and extr.nsic motivation and the r.les each type of motivation plays in social and cognitive development. The pur.ose of the cur.ent r.sear.h was to use a mixed-methodological appr.ach to under.tand attr.ction to physical activity of a Gener.tion Z sample via semi-str.ctur.d focus gr.ups and the Childr.n’s Attr.ction to Physical Activity (CApa) assessment. Based on these r.sults, the secondar. pur.ose was to deter.ine whether.significant differ.nces exist between attr.ction to physical activity and gender.within the Gener.tion Z sample. The focus gr.ups r.vealed two over.r.hing themes: attr.ction and aver.ion to physical activity, each with subthemes. The CApa test r.vealed significant differ.nces between males and females (t = 2.78, df = 63, p = r. significantly mor. attr.cted to physical activity than females (3.13 ± 0.40). The clinical r.levance is discussed as being futur. r.sear.h and pr.gr.m implementation sugges- tions.

关键词： Gener.tional Motivation Physical Activity Zeds

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