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Absorption density control.in waveguide photodiode- anal.sis, design, and demonstration

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Frontiers of Optoel.ctronics 2014年第3期7卷 385-392页

作者： Dingbo CHEN Jeffery Bl.CH Rui WANG paul K. l. YU Department of El.ctrical.and Computer Engineering University of California San Diego 9500 Gilman Dr La Jolla CA 92093 USA

A modal.anal.sis is conducted for anal.zing the absorption profil. of high power waveguide photodiodes designed for anal.g optical.l.nk. The excitation of guided modes with l.rge fil.ing factor in the absorber is identified as a l.miting factor for the performance of waveguide photodiodes at high optical.power, incl.ding power handl.ng capabil.ty, and bandwidth-efficiency product. A waveguide photodiode design, which spatial.y separates the input waveguide from the absorber in the l.teral.direction, is anal.zed and experimental.y demon- strated to suppress the excitation of mode with l.rge fil.ing factor. Photocurrent 〉 60 mA under - 4 V bias is measured, with 0.80 A/W responsivity. This design il.ustrates that high power handl.ng capabil.ty can be achieved without compromising the bandwidth-efficiency product.

关键词： photodiode waveguide thermal.fail.re high power mode excitation

DNA methyl.me study of human cerebel.ar tissues identified genes and pathways possibl. invol.ed in essential.tremor

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Precision Cl.nical.Medicine 2019年第4期2卷 221-234页

作者： Jennifer l.paul Khashayar Dashtipour Zhong Chen Charl.s Wang Center for Genomics School of MedicineLoma Linda UniversityLoma LindaCA 92350USA Division of Movement Disorders Department of NeurologyLoma Linda University Medical CenterLoma LindaCA 92350USA Department of Basic Sciences School of MedicineLoma Linda UniversityLoma LindaCA 92350USA

Background:Essential.tremor(ET)is a neurol.gical.syndrome of unknown origin with poorl. understood etiol.gy and *** is suggested that the cerebel.um and its tracts may be invol.ed in the pathophysiol.gy of *** methyl.me interrogation of cerebel.ar tissue may hel. shine some l.ght on the understanding of the mechanism of the devel.pment of *** study used postmortem human cerebel.um tissue sampl.s col.ected from 12 ET patients and 11 matched non-ET control. for DNA methyl.me study to identify differential.y methyl.ted genes in ***:Using Nugen’s Ovation reduced representation bisul.ite sequencing(RRBS),we identified 753 genes encompassing 938 CpG sites with significant differences in DNA methyl.tion between the ET and the control.*** genes were further anal.zed with Ingenuity Pathway Anal.sis(IPA)by which we identified certain significant pathways,upstream regul.tors,diseases and functions,and networks associated with ***:Our study provides evidence that there are significant differences in DNA methyl.tion patterns between the ET and control.sampl.s,suggesting that the methyl.tion al.eration of certain genes in the cerebel.um may be associated with ET *** identified genes al.ude to the GABAergic hypothesis which supports the notation that ET is a neurodegenerative disease,particul.rl. invol.ing the cerebel.um.

关键词： DNA methyl.me reduced representation bisul.ite sequencing essential.tremor cerebel.um epigenetics CpGs

Environmental.barcoding of the ectomycorrhizal.fungal.genus Cortinarius

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Fungal.Diversity 2013年第1期58卷 299-310页

作者： Sul.ana E.Teasdal. Anne K.Beul.e paul l.Guy David A.Orl.vich Department of Botany University of OtagoPO Box 56Dunedin 9054New Zealand Department of Ecol.gy Evolution and BehaviorCollege of Biological SciencesUniversity of Minnesota1987 Upper Buford CircleSt PaulMN 55108USA

Understanding the rol. of ectomycorrhizal.fungi in pl.nt communities is hampered by a l.ck of knowl.dge about fungal.*** barcoding of the ectomycorrhizal.fungal.genus Cortinarius was used to compare fungal.diversity in soil.from four pl.nt communities:(i)Nothofagus forest(where Cortinarius is common and diverse),(ii)Kunzea forest(where Cortinarius is present but with l.w diversity),(iii)a Pinus radiata pl.ntation(Cortinarius is not thought to be present)and(iv)a sub-Antarctic isl.nd(where known ectomycorrhizal.hosts are absent).PCR primers specific for the ITS region of Cortinarius species were *** was tested in vitro and in sil.co against DNA from basidiocarps of Cortinarius and non-Cortinarius *** primers were tested for their abil.ty to ampl.fy Cortinarius DNA in soil.from forests of the three ectomycorrhizal.forest communities and a range of soil. from the ectomycorrhiza-free subantarctic Campbel. *** diversity of Cortinarius was associated with soil.of al. three ectomycorrhizal.communities,despite Cortinarius being previousl. unrecorded from *** from al. three communities share some ectomycorrhizal.fungi(incl.ding fungi shared between native and exotic hosts),having impl.cations for community succession,introduction of exotic fungi and biodiversity *** Cortinarius was detected from Campbel. Isl.nd *** val.dated mol.cul.r protocol.assessed species diversity in a rapid and cost effective *** biodiversity assessment based on DNA barcoding is more effective at detecting diversity than traditional.methods,but requires careful.consideration of the difference between ectomycorrhizal.fungal.diversity in soil.versus root-tips.

关键词： Cortinarius Internal.transcribed spacer region Ectomycorrhizal.ecol.gy Environmental.DNA Barcoding Taxon-specific primers

Stabl. isotope evidence for trophic niche partitioning in a South African savanna rodent community

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Current Zool.gy 2015年第3期61卷 397-411页

作者： Jacquel.ne CODRON Kevin J DUFFY Nico l.AVENANT Matt SPONHEIMER Jennifer l.ICHl.TER Ol.ver PAINE paul SANDBERG Daryl.CODRON Institute of Systems Science Durban University of Technology Durban South Africa Karoo Pal.eontol.gy Deparl.aent National Museum PO Box 266 Bloemfontein 9301 RSA School.of Mathematics Statistics and Computer Science University of KwaZulu-Natal Private Bag X01 Scottsville 3209 RSA Denartment of Mammal.gv. National.Museum. PO Box 266. Bl.emfontein 9301. RSA Department of Anthropol.gy University of Colorado at Boulder Boulder CO80309 USA Fl.risbad Quaternary Research Department National Museum PO Box 266 Bloemfontein 9301 RSA

Species＇ partitioning of resources remains one of the most integral.components for understanding community assem- bl.. Anal.sis of stabl. carbon and nitrogen isotopes in animal.tissues has the potential.to hel. resol.e patterns of partitioning be- cause these proxies represent the individual.s diet and trophic niche, respectivel.. Using free-ranging rodents in a southern Afri- can savanna as a model.community, we find that syntopic species within habitats occupy distinct isotope niches. Moreover, spe- cies with strongl. overl.pping isotope niches did not overl.p in their spatial.distribution patterns, suggesting an underl.ing effect of competitive excl.sion. Niche conservatism appears to characterize the behaviour of most species in our sampl. - with l.ttl. or no observed changes across habitats - with the exception of one species, Mastomys coucha. This species displ.yed a general.st distribution, being found in simil.r abundances across a variety of habitats. This spatial.pattern was coupl.d with a general.st isotope niche that shifted across habitats, l.kel. in response to changes in species composition over the same spatial.gradient. The case for M. coucha supports contentions that past competition effects pl.yed a significant evol.tionary rol. in shaping community structures of today, incl.ding the absence of strong interspecific niche overl.ps within particul.r habitats. Our study highl.ghts the val.e of stabl. isotope approaches to hel. resol.e key questions in community ecol.gy, and moreover introduces novel.ana- l.tical.approaches to quantifying isotope niche breadths and niche overl.ps that are easil. comparabl. with traditional.metrices

关键词： Competition Diet Niche breadth Niche overl.p Sterkfontein Val.ey

Microbiota-host interpl.y at the gut epithel.al.l.vel.heal.h and nutrition

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Journal.of Animal.Science and Biotechnol.gy 2017年第2期8卷 327-334页

作者： Jean-paul l.l.ès Division of Human Nutrition Division INRA Clermont-Ferrand France Human Nutrition Research Center-West Nantes France

Growing evidence suggests the impl.cation of the gut microbiota in various facets of heal.h and disease. In this review, the focus is put on microbiota-host mol.cul.r cross-tal. at the gut epithel.al.l.vel.with special.emphasis on two defense systems： intestinal.al.al.ne phosphatase（IAP） and inducibl. heat shock proteins（iHSPs）. Both IAP and iHSPs are induced by various microbial.structural.components（e.g. l.popol.saccharide, fl.gel.in, CpG DNA motifs）,metabol.tes（e.g. n-butyrate） or secreted signal.mol.cul.s（e.g., toxins, various peptides, pol.phosphate）. IAP is produced in the smal. intestine and secreted into the l.men and in the interior mil.eu. It detoxifies microbial.components by dephosphoryl.tion and, therefore, down-regul.tes microbe-induced infl.mmation mainl. by inhibiting NF-κB pro-infl.mmatory pathway in enterocytes. IAP gene expression and enzyme activity are infl.enced by the gut microbiota. Conversel., IAP control. gut microbiota composition both directl., and indirectl. though the detoxification of pro-infl.mmatory free l.minal.adenosine triphosphate and infl.mmation inhibition. Inducibl. HSPs are expressed by gut epithel.al.cel.s in proportion to the microbial.l.ad al.ng the gastro-intestinal.tract. They are al.o induced by various microbial.components, metabol.tes and secreted mol.cul.s. Whether iHSPs contribute to shape the gut microbiota is presentl. unknown. Both systems displ.y strong anti-infl.mmatory and anti-oxidant properties that are protective to the gut and the host. Importantl., epithel.al.gene expressions and protein concentrations of IAP and iHSPs can be stimul.ted by probiotics, prebiotics and a l.rge variety of dietary components, incl.ding macronutrients（protein and amino acids, especial.y l.gl.tamine, fat, fiber）, and specific mineral.（e.g. cal.ium）and vitamins（e.g. vitamins K1 and K2）. Some food components（e.g. l.ctins, soybean proteins, various pol.phenol.） may inhibit or disturb these systems. The general.cel.ul.r and mol.cul.

关键词： Diet Gut Inducibl. heat shock protein Infl.mmation Intestinal.al.al.ne phosphatase Microbiota

A Chronic Post-Surgical.Infectious l.mbar Fistul. Providing Protection against Imminent Morbidity: A Case Report and l.terature Review

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Open Journal.of Modern Neurosurgery 2017年第3期7卷 41-48页

作者： Jacob l. Van Orman paul E. Kal.ostian Mojdeh Najl.-Rahim Joseph l. Vanderl.nden Samer S. Ghostine University of Cal.fornia Riverside School.of Medicine Riverside CA USA Department of Neurosurgery University of California at Riverside School of Medicine Riverside CA USA Department of Infectious Disease Riverside Community Hospital Riverside CA USA Department of Vascul.r Surgery Riverside Community Hospital Riverside CA USA

Vertebral.osteomyel.tis (VOM) and spinal.epidural.abscesses (SEA) are rare infections on the spinal.col.mn, more prominentl. seen in intravenous drug users, diabetics and the immunosuppressed. We report an extremel. rare case of a patient with a chronic history of l.mbar post-surgical.cutaneo-spinal.fistul.us infection that was unresponsive to conventional.antibiotic therapy and ul.imatel. required surgical.debridement and spinal.re-instrumentation. The novel.y of this case was the chronic nature of the patient’s condition that was made possibl. onl. by a fortunate post-surgical.cutaneo-spinal.fistul. that withdrew infected particl.s away from the neurol.gical.structures and thus prevented imminent compressive and neurol.gical.deficits, and possibl. eventual.death. This rare case highl.ghts the need for prompt surgical.eval.ation and intervention in patients with progressive VOM or SEA with associated cutaneo-spinal.fistul.s, especial.y in cases where conventional.antibiotic treatments have fail.d. We highl. recommend a l.w threshol. for surgical.debridement and hardware removal.with re-instrumentation as appropriate before a spinal.compressive emergency arises and/or sepsis devel.ps.

关键词： Spinal Epidural Abscess Vertebral Osteomyel.tis Cutaneo-Spinal Fistul. Spinal Reconstruction

Anal.sis of il.al.sodium/bil. acid cotransporter and rel.ted nucl.ar receptor genes in a famil. with mul.ipl. cases of idiopathic bil. acid mal.bsorption

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Worl. Journal.of Gastroenterol.gy 2006年第47期12卷 7710-7714页

作者： Marco Montagnani Anna Abrahamsson Cecil.a Gl.an Gsta Eggertsen Hanns-Ul.ich Marschal. El.sa Ravaiol. Curt Einarsson paul A dawson Dipartimento di Medicina Interna e Gastroenterol.gia Università di Bologna Bologna Italy Center for Applied Biomedi-cal Research Università di Bologna Bologna Italy Center for Gastroenterol.gy and Hepatol.gy Karolinska University Hospital Huddinge Stockholm Sweden Center for Metabol.sm and Endocrinol.gy Karolinska University Hospital Huddinge Stockholm Sweden Department of l.boratory Medicine Division of Clinical Chemistry Karolinska University Hospital Huddinge Stockholm Sweden Department of Internal.Medicine Wake Forest University School of Medicine Winston-Salem NC 27157 United States

The etiol.gy of most cases of idiopathic bil. acid mal.bsorption （IBAH） is unknown. In this study, a Swedish famil. with bil. acid mal.bsorption in three consecutive generations was screened for mutations in the il.al.apical.sodium-bil. acid cotransporter gene （ASBT; gene symbol. Sl.10A2） and in the genes for several.of the nucl.ar receptors known to be important for ASBT expression： the farnesoid X receptor （FXR） and peroxisome prol.ferator activated receptor al.ha （PPARα）. The patients presented with a cl.nical.history of idiopathic chronic watery diarrhea, which was responsive to chol.styramine treatment and consistent with IBAH. Bil. acid absorption was determined using ^75Se-homochol.c acid taurine （SeHCAT）; bil. acid synthesis was estimated by measuring the pl.sma l.vel. of 7α-hydroxy-4-chol.sten-3-one （C4）. The ASBT, FXR, and PPARα genes in the affected and unaffected famil. members were anal.zed using singl. stranded conformation pol.morphism （SSCP）, denaturing HPl., and direct sequencing. No ASBT mutations were identified and the ASBT gene did not segregate with the bil. acid mal.bsorption phenotype. Simil.rl., no mutations or pol.morphisms were identified in the FXR or PPARα genes associated with the bil. acid mal.bsorption phenotype. These studies indicate that the intestinal.bil. acid mal.bsorption in these patients cannot be attributed to defects in ASBT. In the absence of apparent il.al.disease, al.ernative expl.nations such as accel.rated transit through the smal. intestine may be responsibl. for the IBAM.

关键词： Bil. acid mal.bsorption Diarrhea Genetics ^75Se-homochol.c acid taurine test Nucl.ar receptors

Pl.nt regeneration and genetic transformation in switchgrass——A review

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Journal.of Integrative Agricul.ure 2015年第3期14卷 483-493页

作者： paul Merrick Shuizhang Fei Interdepartmental.Graduate Major in Genetics and Genomics Iowa State University Department of Horticul.ure Iowa State University

Switchgrass is native to the tal.grass prairie of North America. It is sel.-incompatibl. and has varied pl.idy l.vel. from dipl.id（2x） to dodecapl.id（12x） with tetrapl.id and octopl.id being the most common. The high yiel.ing potential.and the abil.ty to grow wel. in marginal.l.nds make switchgrass an ideal.species as a dedicated biomass producer for l.gnocel.ul.sic ethanol.production. Genetic transformation is an important tool.for studying gene function and for germpl.sm improvement in switchgrass, the genome of which has been sequenced recentl.. This paper intends to provide a comprehensive review on pl.nt regeneration and genetic transformation in switchgrass. We first reviewed the effect of expl.nts, basal.medium and pl.nt growth regul.tors on pl.nt regeneration in switchgrass, which is a prerequisite for genetic transformation. We then reviewed the progresses on genetic transformation with either the biol.stic or Agrobacterium-mediated method in switchgrass, and discussed various techniques empl.yed to improve the transformation efficiency. Final.y we reviewed the recent progresses on the use of genetic transformation in improving biomass qual.ty such as the reduction of l.gnin, and in increasing biomass yiel. in switchgrass. We al.o provided a future perspective on the use of new genome editing technol.gies in switchgrass and its potential.impact on regul.tory processes.

关键词： switchgrass Panicum virgatum l. pl.nt regeneration genetic transformation biofuel l.gnocel.ul.sic ethanol

Fol.icl.-stimul.ting hormone(FSH)l.vel. prior to prostatectomy are not rel.ted to l.ng-term oncol.gic or cardiovascul.r outcomes for men with prostate cancer

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Asian Journal.of Androl.gy 2022年第1期24卷 21-25页

作者： Kassim Kourbanhoussen France-Hél.ne Joncas Christopher JD Wal.is Hél.ne Hovington Francois Dagenais Yves Fradet Chantal.Guil.emette l.uis l.combe paul Toren Department of Surgery Faculty of MedicineUniversitéLavalCHU de Québec Research CenterOncology DivisionQuebec City G1R3S1Canada Department of Urol.gy Vanderbilt University Medical CenterNashvilleTN 37232USA Institut Universitaire Cardiol.gie et Pneumol.gie de Québec Quebec City G1V 4G5Canada Facul.y of Pharmacy UniversitéLavalCHU de Québec Research CenterQuebec City G1V 4G2Canada

Prior research suggests a l.nk between circul.ting l.vel. of fol.icl.-stimul.ting hormone(FSH)and prostate cancer *** l.vel. may al.o expl.in some of the observed differences in cardiovascul.r events among men treated with gonadotropin-rel.asing hormone(GnRH)antagonists compared to GnRH *** study eval.ates the association between preoperative FSH and l.ng-term cardiovascul.r and oncol.gic outcomes in a cohort of men with l.ng fol.ow-up after radical.*** performed a cohort study util.zing an institutional.biobank with annotated cl.nical.*** l.vel. were measured from cryopreserved pl.sma and compared with sex steroids previousl. measured from the same *** in oncol.gic outcomes between tertil.s of FSH l.vel. were compared using adjusted cox regression *** adverse cardiovascul.r events(MACE)were simil.rl. assessed using hospital.admission diagnostic codes.A total.of 492 patients were incl.ded,with a median fol.ow-up of 13.1(interquartil. range:8.9–15.9)*** sul.ate(DHEA-S)l.vel.,but not other androgens,negativel. correl.ted with FSH l.vel. on l.near regression anal.sis(P=0.03).There was no association between FSH tertil. and outcomes of biochemical.recurrence,time to castrate-resistant prostate cancer,or time to *** were identified in 50 patients(10.2%),with a mean time to first event of 8.8 *** association with FSH tertil. and occurrence of MACE was *** resul.s do not suggest that preoperative FSH l.vel. are significantl. associated with oncol.gic outcomes among prostate cancer patients treated with radical.prostatectomy,nor do these l.vel. appear to be predictors of l.ng-term cardiovascul.r risk.

关键词： cardiovascul.r events fol.icl.-stimul.ting hormone prostate cancer recurrence