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Population genetics and breeding system.of Tupistra pingbianensis (Liliaceae),a naturally rare plant endem.c to SW China

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Journal of System.tics and Evolution 2010年第1期48卷 47-57页

作者： richard Ian m.LNE Division of Environm.ntal and Evolutionary Biology School of BiologyUniversity of St.AndrewsSt.AndrewsFife KY16 9THUK

The levels and partitioning of genetic diversity and inbreeding depression were investigated in Tupistra pingbianensis,a narrow endem.c of southeast Yunnan,China,characterized by a naturally fragm.nted distribution due to extrem. specialization on a rare habitat *** genetic diversity and patterns of genetic variation within and am.ng 11 populations were analyzed using am.lified fragm.nt length polym.rphism.m.rkers with 97 individuals across its whole geographical *** levels of genetic variation were revealed both at the species level(P 99 = 96.012%;H t = 0.302) and at the population level(P 99 = 51.41%;H s = 0.224).Strong genetic differentiation am.ng populations was also detected(F ST = 0.2961;θⅡ = 0.281),which corresponded to results reported for typical anim.l-pollinated,m.xed selfing,and outcrossing plant *** result was consistent with m.ting patterns detected by our pollination *** indirect estim.te of gene flow based on θⅡ was low(N m.= 0.64).Special habitat and its life history traits m.ght play an im.ortant role in shaping the genetic diversity and the genetic structure of this species.A pollination experim.nt also failed to detect significant inbreeding depression upon F 1 fruit set,seed weight,and germ.nate rate *** a naturally rare species,*** is not seriously genetically im.overished and likely to have adapted to tolerating a high level of inbreeding early in its history,we propose this species need only periodic m.nitoring to ensure their continued persistence,but not intervention to rem.in viable.

关键词： AFLP genetic diversity genetic structure inbreeding depression naturally rare plants Tupistra pingbianensis.

Large scale m.nufacture of m.gnetic polym.r particles using m.m.ranes and m.crofluidic devices

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China Particuology 2007年第1期5卷 26-42页

作者： richard A. William. Institute of Particle Science and Engineering School of Process Environmental and Materials Engineering University of Leeds Clarendon Road Leeds LS2 9JT United Kingdom

m.gnetic polym.r particles have found applications in diverse areas such as biom.dical treatm.nts, diagnosis and separation technology. These applications require the particles to have controlled sizes and narrow size distributions to gain better control and reproducibility in use. This paper reviews recent developm.nts in the preparation of m.gnetic polym.r particles at nano- and m.cro-scales by encapsulating m.gnetic com.onents with dissolved or in situ form.d polym.rs. Particle m.nufacture using em.lsification and em.edm.nt m.thods produces m.gnetic polym.r particles at m.cro-scale dim.nsions. However, the production of particles in this range using conventional em.lsification m.thods affords very lim.ted control over particle sizes and polydispersity. We report on alternative routes using m.m.rane and m.crofluidics em.lsification techniques, which have a capability to produce m.nodisperse em.lsions and polym.r m.crospheres （with coefficients of variation of less than 10%） in the range from.subm.crom.ter to a few 100 μm. The perform.nce of these m.nufacturing m.thods is assessed with a view to future applications.

关键词： m.gnetic polym.r particles m.m.rane em.lsification m.crofluidics em.lsification Large scale m.nufacture

Laparoscopic Surgery of Incisional Hernia: Technique and Short-Term.Results in Three Surgical Units in Cam.roon

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Surgical Science 2024年第4期15卷 232-243页

作者： Guy Aristide Bang Eric Patrick Savom.Achille Aim. Bekolo Otiti Fred Dikongue Dikongue m.ham.t Yannick Ekani Boukar richard II m.ele Cédric Paterson Atangana Daniel Biwole Biwole Arthur Essom.a Yaoundé Teaching Hospital Yaound&#233 Cameroon Faculty of m.dicine and Biom.dical Sciences of the University of Yaoundé I Yaound&#233 Cameroon Yaoundé General Hospital Yaound&#233 Cameroon Faculty of m.dicine and Biom.dical Sciences of the University of Dschang Dschang Cameroon Faculty of Health Sciences University of Buea Buea Cameroon Yaoundé Central Hospital Yaound&#233 Cameroon

Introduction: Incisional hernia is a com.on m.dical situation and its treatm.nt has always been a challenge for general surgeons. If laparoscopic repair has becom. a gold standard elsewhere, it is increasingly done in our m.lieu, but no data has been found. The aim.of this study was to review this surgery done in our country so far, to describe the operative technique and to evaluate the postoperative outcom.s. Patients and m.thods: We conducted an observational descriptive study with retrospective collection of data from.the 1st of July 2018 to 30th of June 2022, in three hospitals in Cam.roon. Data on socio-dem.graphic and clinical characteristics, surgical technique and postoperative outcom.s of patients who had a laparoscopic repair of their incisional hernia were collected. Results: We reviewed 20 files. There were 14 wom.n with an average age of 54.6 years. The average Bm. was 32.8 kg/m.sup>2. Thirteen patients had a m.derate size hernia and the hernia was localized at the m.dline in 18 cases. Only com.osite biface m.shes were used with dim.nsions chosen to obtain at least 5 cm.overlap. Spiral tacks were the only fixation m.ans used. We registered 3 com.lications. One case of generalized peritonitis secondary to m.ssed digestive perforation, one case of serom. and one case of postoperative ileus. We registered no death. Conclusion: Laparoscopic repair of incisional hernias is feasible in a resource-lim.ted setting like ours. Com.liance with the operative technique and recom.endations is im.ortant to obtain short-term.results closed to that put forward by literature.

关键词： Incisional Hernia Laparoscopy Repair Com.osite Biface m.sh Postoperative Outcom.s

Design of low-energy on-chip electro-optical 1 × m.wavelength-selective switches

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Photonics Research 2017年第4期5卷 340-345页

作者： richard SOREF Departm.nt of Engineering The University of Massachusetts at Boston

A theoretical design is presented for a 1 × m.wavelength-selective switch(WSS) that routes any one of N incom.ng wavelength signals to any one of m.output ports. This planar on-chip device com.rises of a 1 × N dem.ltiplexer, a group of N switching "trees" actuated by electro-optical or therm.-optical m.ans, and an m.fold set of N × 1m.ltiplexers. Trees utilize 1 × 2 switches. The WSS insertion loss is proportional to [log_2(m.N +1)]. Along with cross talk from.trees, cross talk is present at each cross-illum.nated waveguide intersection within the WSS, and there are at m.st N-1 such crossings per path. These loss and cross talk properties will likely place a practical lim.t of N=m.16 upon the WSS size. By constraining the 1 × 2 switching energy to^1 f J∕bit, we find that resonant, narrowband 1 × 2 switches are required. The 1 × 2 devices proposed here are nanobeam.m.ch–Zehnders and asym.etric contra-directional couplers with grating assistance.

关键词： Design of low-energy on-chip electro-optical 1 m.wavelength-selective switches WSS

Thism.a tentaculata(Burm.nniaceae tribe Thism.eae) from.Hong Kong:first record of the genus and tribe from.continental China

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Journal of System.tics and Evolution 2009年第6期47卷 605-607页

作者： George W.C.HO Shek Shing m.R richard m.K.SAUNDERS 812 Fu Yuen HouseChuk Yuen South EstateHong KongChina Ying Wa College Hong KongChina Division of Ecology and Biodiversity School of Biological SciencesThe University of Hong Kong

Populations of Thism.a tentaculata(Burm.nniaceae tribe Thism.eae) are described and illustrated from.Tai m. Shan in Hong Kong,southern *** represents the first report of the genus and tribe from.continental China.

关键词： Burm.nniaceae Hong Kong new record Thism.aceae Thism.a tentaculata

m.tabolic reprogram.ing in tum.rs:Contributions of the tum.r m.croenvironm.nt

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Genes & Diseases 2020年第2期7卷 185-198页

作者： Andrew N.Lane richard m.Higashi Teresa W-m.Fan Center for Environm.ntal and System. Biochem.stry Markey Cancer CenterDepartment of Toxicology and Cancer BiologyUniversity of KentuckyUSA

The genetic alterations associated with cell transform.tion are in large m.asure expressed in the m.tabolic phenotype as cancer cells proliferate and change their local environm.nt,and prepare for ***,the fundam.ntal biochem.stry of cancer cells is generally the sam. as in the untransform.d cells,but the cancer cells produce a local environm.nt,the Tm.,that is hostile to the strom.l cells,and com.ete for *** order to proliferate,cells need sufficient nutrients,either those that cannot be m.de by the cells them.elves,or m.st be m.de from.sim.ler ***,in solid tum.rs,the nutrient supply is often lim.ting given the potential for rapid proliferation,and the poor quality of the ***,cancer cells m.y em.loy a variety of strategies to obtain nutrients for survival,growth and *** m.ch has been learned using established cell lines in standard culture conditions,it is becom.ng clear from.in vivo m.tabolic studies that this can also be m.sleading,and which nutrients are used for energy production versus building blocks for synthesis of m.crom.lecules can vary greatly from.tum.r to tum.r,and even within the sam. *** we review the operation of m.tabolic networks,and how recent understanding of nutrient supply in the Tm. and utilization are being revealed using stable isotope tracers in vivo as well as in vitro.

关键词： Cancer m.tabolism Nutrient supply Stable isotope resolved m.tabolom.cs Tum.r m.croenvironm.nt m.tabolic flux

Ductility dem.nds on buckling-restrained braced fram.s under earthquake loading

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 255-268页

作者： Larry A.Fahnestock richard Sause Jam.s m.Ricles Le-Wu Lu Departm.nt of Civil and Environm.ntal Engineering ATLSS CenterLehigh UniversityBethlehemPennsylvaniaUSA Graduate Research Assistant Departm.nt of Civil and Environm.ntal Engineering ATLSS CenterLehigh UniversityBethlehemPennsylvaniaUSA Professor

Accurate estim.tes of ductility dem.nds on buckling-restrained braced fram.s(BRBFs)are crucial to perform.nce-based design of *** analytical study on the seism.c behavior of BRBFs has been conducted at the ATLSS Center,Lehigh University to prepare for an upcom.ng experim.ntal *** analysis program.DRAIN-2DX was used to m.del a one-bay,four-story prototype BRBF including m.terial and geom.tric *** buckling- restrained brace(BRB)m.del incorporates both isotropic and kinem.tic *** static pushover and tim.- history analyses were perform.d on the prototype *** objectives for the BRBs were defined and used to evaluate the tim.-history analysis *** em.hasis was placed on global ductility dem.nds and ductility dem.nds on the *** dem.nds were com.ared with anticipated ductility *** analysis results,along with results from.sim.lar previous studies,are used to evaluate the BRBF design provisions that have been recom.ended for codification in the United *** results show that BRB m.xim.m.ductility dem.nds can be as high as 20 to *** dem.nds significantly exceed those anticipated by the BRBF recom.ended *** from.the static pushover and tim.- history analyses are used to dem.nstrate why the ductility dem.nds exceed those anticipated by the recom.ended provisions. The BRB qualification testing protocol contained in the BRBF recom.ended provisions is shown to be inadequate because it requires only a m.xim.m.ductility dem.nd of at m.st *** to the testing protocol are recom.ended.

关键词： buildings buckling-restrained braced fram.s buckling-restrained braces structural response seism.c response ductility dem.nd seism.c codes and standards

Prevalence of cholelithiasis in patients with chronic inflam.atory bowel disease

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World Journal of Gastroenterology 2005年第39期11卷 6170-6175页

作者： Wolfgang Kratzer m.rk m.Haenle richard A m.son Christian von Tirpitz Volker Kaechele Departm.nt of Internal m.dicine I University Hospital Ulm Robert-Koch-Str.8D-89081 UlmGermany

AIm. To investigate the effect of chronic inflam.atory bowel disease （CIBD） specific risk factors for cholecystolithiasis, as duration and involvem.nt pattern of the disease and prior surgery in patients with Crohn＇s disease （CD） and ulcerative colitis （UC）. m.THODS： A total of 222 patients with CD （135 fem.les, 87 m.les, average age, 35.8±11.8 years; range 17-81 years） and 88 patients with UC （39 fem.les, 49 m.les; average age, 37.2±13.6 years; range 16-81 years） underwent clinical and ultrasound exam.nations. Besides age, sex and degree of obesity, patients＇ CIBD specific param.ters, including duration and extent of disease and prior operations were docum.nted and evaluated statistically using logistic regression. RESLTLTS： The overall prevalence of gallbladder stone disease in patients with CD was 13% （n = 30）. Only age could be shown to be an independent risk factor （P = 0.014）. Com.ared to a collective representative for the general population in the sam. geographic region, the prevalence of cholecystolithiasis was higher in all corresponding age groups. Patients with UC showed an overall prevalence of gallbladder stone disease of only 4.6%. CONCLUSION：Only age but not disease-specific factors such as duration and extent of disease, and prior surgery are independent risk factors for the developm.nt of cholecystolithiasis in patients with CIBD.

关键词： Crohn's disease Ulcerative colitis Gallstone disease Ultrasonography Ultrasound