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生物工艺学当前发展水平

世界科学 1980年第3期 21-24页

作者： Bernhard j.ralph 朱金贵

最近几年,微生物学、生物化学、分子生物学和遗传学等生物学科的新成就同化学、化学工程、其它工程学以及数学的新成就相融合而产生一门新的独特的学科——生物工艺学。本文简单地概述了生物工艺学诞生的一些历史发展过程,以及因为这些... 详细信息

最近几年,微生物学、生物化学、分子生物学和遗传学等生物学科的新成就同化学、化学工程、其它工程学以及数学的新成就相融合而产生一门新的独特的学科——生物工艺学。本文简单地概述了生物工艺学诞生的一些历史发展过程,以及因为这些发展过程能很好地说明采用多学科方法解决问题时所产生的相互渗透的丰盛效果。作者力图明确说明生物工艺学核心作用的二个主要方面,即:谋求完成一项具体任务的最佳生物催化系统;设计、建造和管理使这种催化剂发挥其功能的最佳环境。

关键词：生物工艺学领域跨学科微生物学科方法生物化学基础医学

Skeleton-based canonical forms for non-rigid 3D shape retrieval

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Computational Visual Media 2016年第3期2卷 231-243页

作者： david Pickup Xianfang Sun Paul L.Rosin ralph R.Martin School of Computer Science and Informatics Cardiff University

The retrieval of non-rigid 3D shapes is an important task. A common technique is to simplify this problem to a rigid shape retrieval task by producing a bending-invariant canonical form for each shape in the dataset to be searched. It is common for these techniques to attempt to "unbend" a shape by applying multidimensional scaling(MDS) to the distances between points on the mesh, but this leads to unwanted local shape distortions. We instead perform the unbending on the skeleton of the mesh, and use this to drive the deformation of the mesh itself. This leads to computational speed-up, and reduced distortion of local shape detail. We compare our method against other canonical forms: our experiments show that our method achieves state-of-the-art retrieval accuracy in a recent canonical forms benchmark, and only a small drop in retrieval accuracy over the state-of-the-art in a second recent benchmark, while being significantly faster.

关键词： canonical forms shape retrieval skeletons pose invariance

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A comparison of two methods to assess audience-induced changes in male mate choice

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Current Zoology 2012年第1期58卷 84-94页

作者： Ziege, Madlen Hennige-Schulz, Carmen Muecksch, Frauke Bierbach, david Tiedemann, ralph Streit, Bruno Plath, Martin Department of Ecology & Evolution J.W. Goethe University Frankfurt Siesmayerstrasse 70-72 D-60054 Frankfurt am Main Germany Institute of Biochemistry & Biology Unit of Evolutionary Biology & Systematic Zoology University of Potsdam Karl-Liebknecht Str. 24-25 14476 Potsdam Germany

Multidirectional communicative interactions in social networks can have a profound effect on mate choice behavior. Male Atlantic molly Poecilia mexicana exhibit weaker mating preferences when an audience male is presented. This could be a male strategy to reduce sperm competition risk： interacting more equally with different females may be advantageous because ri- vals might copy mate choice decisions. In line with this hypothesis, a previous study found males to show a strong audience effect when being observed while exercising mate choice, but not when the rival was presented only before the choice tests. Audience effects on mate choice decisions have been quantified in poeciliid fishes using association preference designs, but it remains un- known if patterns found from measuring association times translate into actual mating behavior. Thus, we created five audience treatments simulating different forms of perceived sperm competition risk and determined focal males＇ mating preferences by scoring pre-mating （nipping） and mating behavior （gonopodial thrusting）. Nipping did not reflect the pattern that was found when association preferences were measured, while a very similar pattern was uncovered in thrusting behavior. The strongest response was observed when the audience could eavesdrop on the focal male＇s behavior. A reduction in the strength of focal males＇ preferences was also seen after the rival male had an opportunity to mate with the focal male＇s preferred mate. In comparison, the reduction of mating preferences in response to an audience was greater when measuring association times than actual mating behavior. While measuring direct sexual interactions between the focal male and both slimulus females not only the male＇s motivational state is reflected but also females＇ behavior such as avoidance of male sexual harassment [Current Zoology 58 （1）： 84-94, 2012].

关键词： Communication networks Male mate choice Non-independent mate choice Sexual selection Sperm competition risk Audience effect

Anatomic Correlates of Mitral Systolic Anterior Motion in Transposition of the Great Arteries Following Atrial Switch Operation

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Congenital Heart Disease 2023年第3期18卷 267-277页

作者： Norman Aiad Mark V.Sherrid Adam j.Small Youssef Elnabawi jodi Feinberg Leon Axel ralph Mosca T.K.Susheel Kumar Michael Argilla Dan G.Halpern Cardiovascular Division Leon H.Charney Division of CardiologyNYU Langone HealthSchool of MedicineNew York University GrossmanNew YorkUSA Department of Cardiovascular Disease Medical SchoolThe University of MinnesotaMinneapolisUSA The Lillehei Heart Institute MinneapolisMNUSA Radiology Department NYU Langone HealthSchool of MedicineNew York University GrossmanNew YorkUSA Cardiothoracic Surgery Department NYU Langone HealthSchool of MedicineNew York University GrossmanNew YorkUSA Pediatric Cardiology Division NYU Langone HealthSchool of MedicineNew York University GrossmanNew YorkUSA Department of Internal Medicine NYU Langone HealthSchool of MedicineNew York University GrossmanNew YorkUSA

Introduction:We sought to investigate whether the development of sub-pulmonic systolic anterior motion(SAM)may be inherent to the anatomy of the the mitral valve(MV)or affected by external factors,such as a dilated right ventricle or chest abnormalities in d-looped transposition of the great arteries post atrial switch operation(d-TGA/AtS).Methods:Analysis was performed of clinical and cardiac imaging studies acquired on 19 adult patients with d-TGA/AtS(age 42±6 years old,56%male)between 2015–*** data included mitral apparatus anatomy,and CT/MRI data included biventricular dimensions,function,and Haller index(HI)for pectus ***:Patients with leaflet SAM(n=6)compared to patients without SAM(n=13)had higher MV protrusion height(2.3±0.5 vs.1.5±0.4 cm,p≤0.01)and longer anterior MV leaflet length(3.1±0.4 cm vs.2.6±0.3 cm p≤0.05),when compared to those ***/MRI showed higher sub-pulmonic left ventricular ejection fraction(LVEF)in the SAM group(71%±8%vs.54%±7%,respectively).RV size and function,significant chest deformity(HI>3.5),presence of a ventricular lead pacemaker,and septal thickness did not play a role in development of ***:An elongated mitral apparatus is associated with the development of SAM,and the development of left ventricular outflow tract obstruction(LVOTO),in d-TGA/*** hyperkinesia is associated with *** RV dimensions,septal thickness,and degree of chest deformity did not differ significantly between subjects with SAM and those without.

关键词： d-loop transposition of the great arteries mustard operation senning operation systolic anterior motion of the mitral valve echocardiography cardiac MRI

Solving a bottleneck in animal models of peyronie＇s disease

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Asian journal of Andrology 2014年第4期16卷 639-639页

作者： Selim Cellek William Stebbeds david j.ralph Cranfield University Bedfordshire University College London Hospital London UK

Peyronie＇s disease is characterized by the formation of a fibrous plaque in the tunica albuginea （TA） of the penis. It is a benign condition of unclear etiology, resulting in deformities such as curvature, indentation or shortening. The disease has been shown to be prevalent, especially in older men, and affects quality of life, principally through pain during erection, erectile dysfunction and associated psychological impact.

关键词： PROTEIN EXPRESSION RAT INCREASE

New advances in visual computing for intelligent processing of visual media and augmented reality

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Science China(Technological Sciences) 2015年第12期58卷 2210-2211页

作者： WANG juHong ZHANG SongHai MARTIN ralph R. Department of Computer Science and Technology Tsinghua University School of Computer Science & Informatics Cardiff University

Visual imagery constitutes the most important sensory information for *** entire field of acquiring,analyzing and synthesizing visual data by means of computers is called visual *** has an extraordinarily wide range of applications,including for example:industrial quality control,street view and driver assistance systems,robot navigation,multimedia systems,and computer games.

关键词： Augmented reality Intelligent computing

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Magnetically actuated glaucoma drainage devicefor regulating intraocular pressure afterimplantation

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Microsystems & Nanoengineering 2023年第4期9卷 91-105页

作者： Inês C.F.Pereira ralph j.S.van Mechelen Hans M.Wyss Leonard Pinchuk Henny j.M.Beckers jaap M.j.den Toonder Microsystems Department of Mechanical EngineeringEindhoven University of Technology5600MB EindhovenThe Netherlands Institute for Complex Molecular Systems(ICMS) Eindhoven University of Technology5600MB EindhovenThe Netherlands University Eye Clinic Maastricht Maastricht University Medical Centre+(MUMC+)6202AZ MaastrichtThe Netherlands InnFocus Inc.a Santen CompanyMiamiFlorida 33186USA Ophthalmic Biophysics Center Bascom Palmer Eye InstituteUniversity of Miami Miller School of MedicineMiamiFlorida 33136USA

The key risk factor for glaucoma is increased intraocular pressure (IOP). Glaucoma drainage devices implanted in theeye can reduce IOP and thus stop disease progression. However, most devices currently used in clinical practice arepassive and do not allow for postsurgical IOP control, which may result in serious complications such as hypotony (i.e.,excessively low IOP). To enable noninvasive IOP control, we demonstrate a novel, miniature glaucoma implant that willenable the repeated adjustment of the hydrodynamic resistance after implantation. This is achieved by integrating amagnetic microvalve containing a micropencil-shaped plug that is moved using an external magnet, thereby openingor closing fluidic channels. The microplug is made from biocompatible poly(styrene-block-isobutylene-block-styrene)(SIBS) containing iron microparticles. The complete implant consists of an SIBS drainage tube and a housing elementcontaining the microvalve and fabricated with hot embossing using femtosecond laser-machined glass molds. Usingin vitro and ex vivo microfluidic experiments, we demonstrate that when the microvalve is closed, it can providesufficient hydrodynamic resistance to overcome hypotony. Valve function is repeatable and stable over time. Due to itssmall size, our implant is a promising, safe, easy-to-implant, minimally invasive glaucoma surgery device.

关键词： enable implantation overcome

Magnetic Properties of Y3-2xCa2xFe5-xVxO12Garnets

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Advances in Materials Physics and Chemistry 2012年第3期2卷 116-120页

作者： Imaddin A. Al-Omari ralph Skomski david j. Sellmyer Department of Physics and Nebraska Center for Materials and Nanoscience University of Nebraska-Lincoln Lincoln USA Department of Physics P.O. Box 36 Sultan Qaboos University Muscat Sultanate of Oman

A comprehensive study of the magnetic properties of Y3-2xCa2xFe5-xVxO12 (0 ≤ x ≤ 1) has been performed. The garnet ferrites samples were prepared by the ceramic technique, and X-ray diffraction analysis indicates the formation of single cubic phase. Vibrating sample magnetometry (VSM) and a superconducting quantum-interference device (SQUID) were used to measure the magnetic properties, especially the magnetization and thermo-magnetic behavior. The magnetization curves exhibit the typical characteristics of ferrimagnetic materials at both 4.2 K and at room temperature. The samples have a low coercivities (between 20 and 40 Oe) and saturation magnetizations as high as 36 emu/g at 4.2 K. The saturation magnetization decreases with V and Ca contents, reaching about 8 emu/g at 4.2 K (x = 1). For all samples, the saturation magnetization decreases with increasing temperature, whereas the Curie temperature increases for small values of x, from 557 K for x = 0 to a maximum of 590 K for x = 0.2. For larger values of x, it decreases and reaches 525 K for x = 1.0. The basic experimental trends reflect the occupancy of the tetrahedral 24d sites by vanadium in combination with the predominant intersublattice exchange constant jad, although the nonzero magnetization at x = 1.0 indicates that about 10% of the substituted V atoms goes onto the octahedral 16a sites.

关键词： Yttrium Iron Garnets Curie Temperature Saturation Magnetization Magnetic Moment

Trends of Extreme Precipitation in Eastern China and Their Possible Causes

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Advances in Atmospheric Sciences 2015年第8期32卷 1027-1037页

作者： LIU Run LIU Shaw Chen ralph j.CICERONE SHIU Chein-jung LI jun WANG jingli ZHANG Yuanhang State Key joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Research Center for Environmental Changes Academia Sinica Department of Atmospheric Science NCU National Academy of Sciences Earth System Science University of California Institute of Urban Meteorology of China Meteorological Administration

Significant increases of heavy precipitation and decreases of light precipitation have been reported over widespread regions of the globe. Global warming and effects of anthropogenic aerosols have both been proposed as possible causes of these changes. We examine data from urban and rural meteorological stations in eastern China （1955-2011） and compare them with Global Precipitation Climatology Project （GPCP） data （1979-2007） and reanalysis data in various latitude zones to study changes in precipitation extremes. Significant decreases in light precipitation and increases in heavy precipitation are found at both rural and urban stations, as well as low latitudes over the ocean, while total precipitation shows little change. Characteristics of these changes and changes in the equatorial zone and other latitudes suggest that global warming rather than aerosol effects is the primary cause of the changes. In eastern China, increases of annual total dry days （28 days） and ） 10 consecutive dry days （36%） are due to the decrease in light precipitation days, thereby establishing a causal link among global warming, changes in precipitation extremes, and higher meteorological risk of floods and droughts. Further, results derived from the GPCP data and reanalysis data suggest that the causal link exists over widespread regions of the globe.

关键词： extreme precipitation global warming aerosols meteorological risk of floods and droughts

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