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Two-phase air-water f.ows: Scale ef.ects in physical modeling

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Journal of.Hydrodynamics 2014年第2期26卷 291-298页

作者： Pf.STER Michael CHANSON hubert Ecole Polytechnique f.dérale de Lausanne (EPf.) Laboratory of Hydraulic Constructions (LCH) The University of.Queensland School of Civil Engineering

Physical modeling represents probably the oldest design tool in hydraulic engineering together with analytical approaches. In f.ee surf.ce f.ows, the similitude based upon a f.oude similarity allows f.r a correct representation of.the dominant f.rces, namely gravity and inertia. As a result f.uid f.ow properties such as the capillary f.rces and the viscous f.rces might be incorrectly reproduced, af.ecting the air entrainment and transport capacity of.a high-speed model f.ow. Small physical models operating under a f.oude similitude systematically underestimate the air entrainment rate and air-water interf.cial properties. To limit scale ef.ects, minimal values of.Reynolds or Weber number have to be respected. The present article summarizes the physical background of.such limitations and their combination in terms of.the Morton number. Based upon a literature review, the existing limits are presented and discussed, resulting in a series of.more conservative recommendations in terms of.air concentration scaling. f.r other air-water f.ow parameters, the selection of.the criteria to assess scale ef.ects is critical because some parameters （e.g., bubble sizes, turbulent scales） can be af.ected by scale ef.ects, even in relatively large laboratory models.

关键词： air entrainment hydraulic structures physical modeling scale ef.ects two-phase f.ow Morton number

Pathogenic Variation and Occurrence of.Multiple Resistance-Breaking <i>Rice yellow mottle virus</i>Strains in Tanzania

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American Journal of.Plant Sciences 2017年第8期8卷 1820-1841页

作者： Judith hubert Herman J. f. Lyimo Ashura Luzi-Kihupi Department of.Crop Science and Horticulture Sokoine University of Agriculture Morogoro Tanzania

Rice yellow mottle virus (RYMV) is a major biotic constraint f.r rice production in Af.ica. The resistance-breaking ability of.Tanzanian RYMV strains and phylotypes (S4lm (Tz526), S4lv (Tz516), S4ug (Tz508), S5 (Tz429, Tz445), S6c (Tz486) and S6w (Tz539)) were tested by inoculating rice cultivars with RYMV1 resistant alleles (Gigante (rymv1-2), Tog12387 (rymv1-3), Tog5681 (rymv1-3), Tog5438 (rymv1-4), Tog5672 (rymv1-4+rymv2) and Tog5674 (rymv 1-5)) in a screen house. The results revealed multiple resistance-breaking strains and phylotypes on resistant cultivars Gigante, Tog12387, Tog5438 and Tog5681. However, the resistance breakdown was highly variable depending on the strain used, and disease severity ranged f.om 11% - 75.3%. The virulence potential of.RYMV phylotype S4lm (Tz526) was similar to phylotype S6w (Tz539). The impact of.strains and phylotypes on yield and its components in rice cultivars revealed highly signif.cant dif.erences (P ≤ 0.001). The lowest percent plant height reduction (2.8%), number of.tillers per plant (2.5%), 1000 grain weight (2.7%), spikelet sterility (3.5%) and yield (5%) was recorded in rice cultivar Gigante inoculated with RYMV phylotype S6c (Tz486). Phylotype S6c (Tz486) despite being less virulent compared to other strains, its virus titer in rice cultivar Gigante (1.833) was higher than S5 (Tz429, Tz445) inoculated on Tog5674 (0.171, 0.207) and S6w (Tz539) inoculated on Tog5681 (0.283). The resistant-breaking strain S5 (Tz445) multiplied in resistant rice cultivar Tog5674 without inducing visible symptoms but showed positive reaction to ELISA with low virus titer. The strain S5 overcame wide range of.resistant alleles including rymv1-2, rymv1-3, rymv1-4 and rymv1-5 resistance, with exception of.rymv1-4 + rymv2. The current results gave a new perspective f.r f.ture identif.cation of.resistance-breaking mutations through sequencing of.the RYMV genome in inf.cted rice cultivars and mutagenesis of.an inf.ctious viral clone usef.l f.r

关键词： Pathogenic Variation Virulence Multiple Resistance-Breaking RYMV Strains Yield Losses Tanzania

Geographical Variation, Distribution and Diversity of.<i>Rice Yellow Mottle Virus</i>Phylotypes in Tanzania

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American Journal of.Plant Sciences 2017年第6期8卷 1264-1284页

作者： Judith hubert Herman J. f. Lyimo Ashura Luzi-Kihupi Department of.Crop Science and Production Sokoine University of Agriculture Morogoro Tanzania

Rice yellow mottle virus (RYMV) is the most important disease of.rice in Af.ica. The disease was f.rst observed in1966 inKenya but has now spread in all rice-growing countries of.Sub-Saharan Af.ica. In Tanzania, its distribution has been restricted to the major rice-growing regions. However, the knowledge on RYMV genetic diversity relies on a limited number of.coat protein sequences. Previous studies revealed the presence of.the phylotypes S4lv, S4lm and strain S5 in Mwanza, Mbeya and Morogoro regions, respectively, and strain S6 in Kilimanjaro region and Pemba Island. Surveys were conducted during the cropping seasons 2013-2014 in eight rice-growing regions of.Tanzania to determine geographical variations and phylotypes of.RYMV and the inf.uence of.environment f.ctors on its distribution and diversity. A total of.185 rice f.elds were surveyed. Results indicate that prevalence, severity and phylotypes of.RYMV varied signif.cantly with rainf.ll intensity, temperature and relative humidity (P ≤ 0.01). The highest prevalence was f.und in Morogoro (82%), Mbeya (80%) and Arusha (67.33%) regions whereas Kigoma (9.33%), Rukwa (11.33%) and Shinyanga (18.67%) had the lowest RYMV prevalence. In each region, RYMV prevalence was higher in 2014 than in 2013. The phylotypes S4lm and new determined phylotypes (S6c and S6w) were highly adapted to low temperature (13.3°C) and rainf.ll (13.7 mm) areas. f.r the f.rst time, strains f.om the phylotype S4ug were f.und outside Uganda, in Kilimanjaro region. Strain S4lv (phylotype Lake Victoria) was f.und f.r the f.rst time in Arusha region. The strain S4lm was f.und in Mbeya, Morogoro and Rukwa regions. Strains S4lm and S4lv were also f.und in Shinyanga and Kigoma regions, respectively. The strain S5 was still restricted to Morogoro but extended to new locations such as Ulanga district. Strain S6 was f.und in several new areas and new phylotypes of.S6 (S6c and S6w) are reported in this study.

关键词： Rice Yellow Mottle Virus Prevalence Severity Environmental f.ctors Tanzania

Screening f.r hepatocellular carcinoma by Egyptian physicians

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World Journal of.Gastrointestinal Oncology 2015年第9期7卷 161-171页

作者： Sahar M Hassany Ehab f.Abdou Moustaf. Mohamed El Taher Af.f.Adel Abdeltwab hubert E Blum Department of.Tropical Medicine and Gastroenterology Assiut University Assiut Hospital f.r f.brile Illnesses Department of.Internal Medicine Ⅱ Freiburg University

AIM: To assess the practice of.Egyptian physicians in screening patients f.r hepatocellular carcinoma(HCC). METHODS: The study included 154 physicians f.om all over Egypt caring f.r patients at risk f.r HCC. The study was based on a questionnaire with 20 items. Each questionnaire consisted of.two parts:(1) personal inf.rmation regarding the physician(name, age, specialty and type of.health care setting); and(2) prof.ssional experience in the care of.patients at risk f.r HCC development(screening, knowledge about the cause and natural course of.liver diseases and HCC risk). RESULTS: Sixty-eight percent of.doctors with an MD degree, 48% of.doctors with a master degree or a diploma and 40% of.doctors with a Bachelor of.Medicine, Bachelor of.Surgery certif.cate considered the hepatitis C virus(HCV) genotype as risk f.ctor f.r HCC development(P f.physicians specialized in tropical medicine, internal medicine or gastroenterology and 67% of.physicians in other specialties advise patients to undergo screening f.r HCV and hepatitis B virus inf.ction as well as liver cirrhosis(P f.doctors in University Hospitals and 69% of.Ministry of.Health(MOH) doctors consider HCV inf.ction as the leading cause of.HCC in Egypt(P f.doctors with an MD degree, 55% of.doctors with a master degree or a diploma, 56% of.doctors with an MBBCH certif.cate, 74% of.doctors in University Hospitals and 46% of.MOH hospital doctors consider abdominal ultrasonography as the most important investigation in HCC screening(P f.ve percent of.physicians in tropical medicine, internal medicine or gastroenterology and 37% of.physicians in other specialties recommend as HCC screening interval of.3 mo(P f.doctors with an MD degree, 50% of.doctors with a master degree or diploma and 60% of.doctors with an MBBCH certif.cate f.llow the same ***: In Egypt, physicians spe

关键词： Hepatocellular carcinoma Egyptian physicians Scree

Saliency-based f.amework f.r f.cial expression recognition

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f.ontiers of.Computer Science 2019年第1期13卷 183-198页

作者： Rizwan Ahmed KHAN Alexandre MEYER hubert KONIK Saida BOUAKAZ Universite de Lyon CNRSLIRISUMR5205Universite Lyon 1Lyon F-69622France f.culty of.Inf.rmation Technology Barrett Hodgson UniversityKarachi 74900Pakistan Laboratoire hubert Curien UMR5516Universite Jean MonnetSaint-Etienne 42000France

This article proposes a novel f.amework f.r the recognition of.six universal f.cial *** f.amework is based on three sets of.f.atures extracted f.om a f.ce image:entropy,brightness,and local binary ***, saliency maps are obtained using the state-of.the-art saliency detection algorithm "f.equency-tuned salient region detection".The idea is to use saliency maps to determine appropriate weights or values f.r the extracted f.atures (i.e.,brightness and entropy).We have perf.rmed a visual experiment to validate the perf.rmance of.the saliency detection algorithm against the human visual *** movements of.15 subjects were recorded using an eye-tracker in f.ee-viewing conditions while they watched a collection of.54 videos selected f.om the Cohn-Kanade f.cial expression *** results of.the visual experiment demonstrated that the obtained saliency maps are consistent with the data on human ***,the perf.rmance of.the proposed f.amework is demonstrated via satisf.ctory classif.cation results achieved with the Cohn-Kanade database,f.-NET f.ED database, and Dartmouth database of.children's f.ces.

关键词： f.cial expression recognition classif.cation salient regions entropy brightness local binary pattern

Limited Spatial Transf.rability of.the Relationships Between Kriging Variance and Soil Sampling Spacing in Some Grasslands of.Ireland:Implications f.r Sampling Design

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Pedosphere 2019年第5期29卷 577-589页

作者： SUN Xiaolin WANG Huili Dermot f.RRISTAL f. Weijun hubert TUNNEY Chaosheng ZHANG Guangdong Provincial Key Laboratory f.r Urbanization and Geo-simulation School of Geography and PlanningSun Yat-sen UniversityGuangzhou 510275 (China) State Key Laboratory of.Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008 (China) International Network f.r Environment and Health School of Geography and ArchaeologyNational University of IrelandGalway H91 TK33 (Ireland) Guangxi f.restry Research Institute Nanning 530002 (China) Crop Science Department TeagascOak ParkCarlow (Ireland) School of.Environmental and Resource Sciences Zhejiang 4&F UniversityLirVan 311300 (China) Teagasc Johnstown Castle Research CentreWexford (Ireland)

Sampling plays an important role in acquiring precise soil inf.rmation required in modern agricultural production worldwide, which determines both the cost and quality of.f.nal soil mapping products. f.r sampling design, it has been proposed possibile to transf.r the relationships between kriging variance and sampling grid spacing f.om an area with existing inf.rmation to other areas with similar soil-f.rming environments. However, this approach is challenged in practice because of.two problems: i) dif.erent population vaxiograms among similar areas and ii) sampling errors in estimated variograms. This study evaluated the ef.ects of.these two problems on the transf.rability of.the relationships between kriging variance and sampling grid spacing, by using spatial data simulated with three variograms and soil samples collected f.om f.ur grasslands in Ireland with similar soil-f.rming environments. Results showed that the variograms suggested by dif.erent samples collected with the same grid spacing in the same or similar areas were dif.erent, leading to a range of.mean kriging variance (MKV) f.r each grid spacing. With increasing grid spacing, the variation of.MKV f.r a specif.c grid spacing increased and deviated more f.om the MKV generated using the population variograms. As a result, the spatial transf.rability of.the relationships between kriging variance and grid spacing f.r sampling design was limited.

关键词： Key Words. geostatistics, population variogram, sampling error, sampling grid spacing soil-f.rming environment soil inf.rmation soil mapping spatial variability

Open channel-based microchip electrophoresis interf.ced with mass spectrometry via electrostatic spray ionization

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Chinese Chemical Letters 2016年第1期27卷 85-87页

作者： Yan Deng Liang Qiao Natalia Gasilova Xin-Xiang Zhang hubert H.Girault Beijing National Laboratory f.r Molecular Sciences (BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry Peking University Laboratoire d’Electrochimie Physique et Analytique Ecole Polytechnique Fédérale de Lausanne

The coupling between open channel-based microchip electrophoresis and mass spectrometry via electrostatic spray ionization is proposed f.r in situ detection of.f.actionated analytes. Electrophoretic separation is perf.rmed in an open channel f.bricated in a plastic substrate. The solvent of.background electrolyte is evaporated f.om the open channel because of.Joule heating during electrophoresis, leaving the dried electrophoretic bands to be directly analyzed by mass spectrometry via scanning electrostatic spray ionization. Proof.of.concept results are obtained with f.uorescent dyes and antibiotics as the test samples, demonstrating an ef.icient on-chip detection platf.rm based on the electrophoresis and electrostatic spray ionization mass spectrometry.

关键词： Open channel Microchip electrophoresis Interf.ce Electrostatic spray ionization mass spectrometry

Pseudomonas exotoxin antisense RNA selectively kills hepatitis B virus inf.cted cells

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World Journal of.Gastroenterology 2008年第18期14卷 2810-2817页

作者： Peter Haf.emeyer Ulrich Brinkmann Elizabeth Brinkmann Ira Pastan hubert E Blum Thomas f.Baumert Department of.Medicine Ⅱ University Hospital Freiburg Hugstetterstrasse 55 Freiburg D-79106 Germany Roche Diagnostics Nonnenwald 2 Penzberg D-82377 Germany National Cancer Institute National Institutes of Health Bethesda United States Inserm unit 748 Université Louis Pasteur 3 Rue Koeberle Strasbourg F-67000 France

AIM: To present an approach f.r selectively killing retrovirus-inf.cted cells that combines the toxicity of.Pseudomonas exotoxin (PE) and the presence of.reverse transcriptase (RT) in inf.cted cells. METHODS: PE antisense toxin RNA has palindromic stem loops at its 5' and 3' ends enabling self.primed generation of.cDNA in the presence of.RT. The RT activity expressed in retrovirus-inf.cted cells converts "antisense-toxin-RNA" into a lethal toxin gene exclusively in these cells. RESULTS: Using cotransf.ction studies with PE-expressing RNAs and β-gal expressing reporter plasmids, we show that, in HepG2 and HepG2.2.15 hepatoma cells as well as in duck hepatitis B virus (DHBV) inf.cted cells, HBV or DHBV-polymerase reverse transcribe a lethal cDNA copy of.an antisense toxin RNA, which is composed of.sequences complementary to a PE gene and eukaryotic transcription and translation signals. CONCLUSION: This f.nding may have important implications as a novel therapeutic strategy aimed at the elimination of.HBV inf.ction.

关键词： Gene therapy Pseudomonas exotoxin Retrovirus Reverse transcription

f.rmation of.Slow Electron Pairs in an External Coulomb f.eld

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Journal of.Modern Physics 2017年第7期8卷 1029-1042页

作者： hubert Klar Retired f.om f.kultä t f.r Physik University of Freiburg Freiburg im Breisgau Germany

The wave equation f.r two electrons in an external Coulomb f.eld (helium-like atoms) has been shown to be a problem in a three-dimensional half.space. The wave-equation becomes quasi-separable in inertial coordinates. This allows to work out the electron motion in the f.ame of.principal inertia axes. We f.nd that non-adiabatic coupling terms constitute a f.ctitious f.rce and lead to a def.rmation of.the static potential surf.ce. Incoming and outgoing modes of.electron pairs are studied in detail, and applied to the threshold ionization of.hydrogen-like atoms by electrons. Our analysis conf.rms the classical work by Wannier. However, we go beyond Wannier and present bending and stretch vibrations of.electron pairs. The bending vibration has no inf.uence onto the total ionization cross-section. The pair f.rmation below threshold destroys the existence of.high double Rydberg resonances. f.nally, we describe the propagation of.an electron pair through a linear chain of.Rydberg atoms.

关键词： Dominant Correlation Wannier Threshold Law Electron Pairs