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Cholera outbreak caused by drinking lake water contaminated with human faeces in Kaiso Village,Hoima District,western Uganda,October 2015

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Infectious Diseases of Poverty 2017年第1期6卷 1294-1300页

作者： David w.Oguttu A.Okullo G.Bwire P.Nsubuga A.R.Ario Uganda Public Health Fellowship Program-Field Epidemiology Track P.O.Box 7272KampalaUganda Ministry of Health KampalaUganda African Field Epidemiology Network KampalaUganda

Background:On 12 October 2015,a cholera outbreak involving 65 cases and two deaths was reported in a fishing village in Hoima District,western *** initial response by the local health department,the outbreak *** conducted an investigation to identify the source and mode of transmission,and recommend evidenceled interventions to control and prevent cholera outbreaks in this ***:we defined a suspected case as the onset of acute watery diarrhoea from 1 October to 2 November 2015 in a resident of Kaiso Village.A confirmed case was a suspected case who had Vibrio cholerae isolated from *** found cases by record review and active community case *** performed descriptive epidemiologic analysis for hypothesis *** an unmatched case-control study,we compared exposure histories of 61 cases and 126 controls randomly selected among asymptomatic village *** also conducted an environmental assessment and obtained meteorological data from a weather ***:we identified 122 suspected cases,of which six were culture-confirmed,47 were confirmed positive with a rapid diagnostic test and two *** two deceased cases had onset of the disease on 2 October and 10 October,*** rainfall occurred on 7-11 October;a point-source outbreak occurred on 12-15 October,followed by continuous community transmission for two *** residents usually collected drinking water from three lakeshore points-A,B and C:9.8%(6/61)of case-persons and 31%(39/126)of control-persons were found to usually use point A,21%(13/61)of case-persons and 37%(46/126)of control-persons were found to usually use point B(OR=1.8,95%CI:0.64-5.3),and 69%(42/61)of case-persons and 33%(41/126)of control-persons were found to usually use point C(OR=6.7;95%CI:2.5-17)for water *** case-persons(61/61)and 93%(117/126)of control-persons reportedly never treated/boiled drinking water(OR=∞,95%CIFisher:1.0-∞).The village’s piped water syste

关键词： Cholera Outbreak Faeces Lake water Uganda

Synchrotron micro-scale measurement of metal distributions in Phragmites australis and Typha latifolia root tissue from an urban brownfield site

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Journal of Environmental Sciences 2016年第3期28卷 172-182页

作者： Huan Feng Yu Qian Frank J.Gallagher weiguo Zhang Lizhong Yu Changjun Liu Keith w.Jones Ryan Tappero Department of Earth and Environmental Studies Montclair State University Urban Forestry Program Department of EcologyEvolution and Natural ResourcesRutgersThe State University of New Jersey State Key Laboratory of Estuarine and Coastal Research East China Normal University Biological Environmental and Climate Sciences DepartmentBrookhaven National Laboratory Photon Sciences Directorate Brookhaven National Laboratory

Liberty State Park in New Jersey,usA,is a ＂brownfield＂ site containing various levels of *** investigate metal uptake and distributions in plants on the brownfield site,Phragmites australis and Typha latifolia were collected in Liberty State Park during the growing season（May–September）in 2011 at two sites with the high and low metal loads,*** objective of this study was to understand the metal（Fe,Mn,Cu,Pb and Zn）concentration and spatial distributions in *** and *** root systems with micro-meter scale resolution using synchrotron X-ray microfluorescence（μXRF）and synchrotron X-ray computed microtomography（μCMT）*** root structure measurement by synchrotron μCMT showed that high X-ray attenuation substance appeared in the *** μXRF measurement showed that metal concentrations and distributions in the root cross-section between epidermis and vascular tissue were statistically *** correlations were found between metals（Cu,Mn,Pb and Zn）and Fe in the epidermis,implying that metals were scavenged by Fe *** results from this study suggest that the expression of metal transport and accumulation within the root systems may be element *** information derived from this study can improve our current knowledge of the wetland plant ecological function in brownfield remediation.

关键词： Phragmites australis Typha latifolia Trace metals Synchrotron radiation technique Brownfield

Q-Switched Erbium-Doped Fiber Laser using Cadmium Selenide Coated onto Side-Polished D-Shape Fiber as Saturable Absorber

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Chinese Physics Letters 2018年第10期35卷 27-30页

作者： M.F.M.Rusdi M.B.H.Mahyuddin A.A.Latiff H.Ahmad S.w.Harun Photonics Engineering Laboratory Department of Electrical Engineering Faculty of EngineeringUniversity of Malaya Faculty of Electronic and Computer Engineering Universiti Teknikal Malaysia Melaka Photonic Research Center University of Malaya Department of Physics Faculty of Science and Technology Airlangga University

A stable Q-switched erbium doped fiber laser emitting at 1558 nm is demonstrated using a cadmium selenide（CdSe） material coated onto a side-polished D-shape fiber as the saturable absorber（SA）. By elevating the input pump power from the threshold of 91 mw to the maximum available power of 136 mw, a pulse train with a maximum repetition rate of 57.44 kHz, minimum pulse width of 3.76 us, maximum average output power of7.99 mw, maximum pulse energy of 0.1391 uJ, and maximum peak power of 36.99 mw are obtained. The signalto-noise ratio of the spectrum is measured to be around 75 dB. This CdSe based SA is simple, robust, and reliable,and thus suitable for making a portable pulse laser source.

关键词： SA Q-Switched Erbium-Doped Fiber Laser using Cadmium Selenide Coated onto Side-Polished D-Shape Fiber as Saturable Absorber

Improving weld formability by a novel dual-rotation bobbin tool friction stir welding

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Journal of Materials Science & Technology 2018年第1期34卷 135-139页

作者： F.F.wang w.Y.Li J.Shen Q.wen J.F.dos Santos State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding Technologies Northwestern Polytechnical University Helmholtz-Zentrum Geesthacht Institute of Materials Research Materials Mechanics China Academy of Launch Vehicle Technology Beijing Institute of Astronautical Systems Engineering

A novel dual-rotation bobbin tool friction stir welding （DBT-FSw） was developed, in which the upper shoulder （us） and lower shoulder （LS） have different rotational speeds. This process was tried to weld 3.2 mm thick alunlinum-lithium alloy sheets. The metallographic analysis and torque measurement were carried out to characterize the weld formabiliw. Experimental results show that compared to conven- tional bobbin tool friction stir welding, the DBT-FSw has an excellent process stability, and can produce the defect-free joints in a wider range of welding parameters. These can be attributed to the significant improvement of material flow caused by the formation of a staggered layer structure and the unbalanced force between the us and LS during the DBT-FSw process.

关键词： Bobbin tool friction stir welding Dual rotation Material flow Microstructure Microhardness

Characterization of organic-rich mineral debris revealed by rapid glacier retreat, Indren Glacier, European Alps

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Journal of Mountain Science 2021年第6期18卷 1521-1536页

作者： FREPPAZ Michele wILLIAMS Mark w. GABRIELI Jacopo GORRA Roberta MANIA Ilaria ASCHER-JENULL Judith EGLI Markus CELI Luisella Department of Agriculture Forest and Food SciencesUniversity of TurinLargo Paolo Braccini 210095 Grugliasco(TO)Italy NatRisk Research Centre on Natural Risks in Mountain and Hilly Environments University of TurinLargo Paolo Braccini 210095 Grugliasco(TO)Italy Institute of Arctic and Alpine Research and Department of Geography University of Colorado at BoulderUCB 450BoulderCO 80309USA CNR-ISP(Consiglio Nazionale delle Ricerche Istituto di Scienze Polari)via Torino 15530172 Venezia-MestreItaly Institute of Microbiology University of InnsbruckTechnikerstraße 256020 InnsbruckAustria Department of Geography University of ZurichWinterthurerstrasse 1908057 ZurichSwitzerland

In the summer of 2003 and 2004, characterized by a rapid glacier retreat, a stony surface covered by well-structured organic-rich mineral debris was observed very close to the Indren glacier terminus(Monte Rosa Massif, Nw Italy, 3100 m ASL), on an area covered by the glacier tongue till the year before. The origin and type of this organicrich material were investigated, in order to detect their characteristics, potential sources and fate within the foreland system. The deposits were dated using Carbon-14 and analyzed for the chemical characteristics of the organic component, the elemental composition of the mineral fraction and presence of microbial markers. The material, granular and dark in color, had a total organic carbon(TOC) content ranging between 17.4 ± 0.39 and 28.1 ± 0.63 g kg^(-1) dry weight(dw), significantly higher than the surrounding glacial till(~ 1.4 g kg^(-1) dw), although only 0.33% of it was in water soluble form. Microbial carbon(C) and nitrogen(N) accounted for 10.6% and 3.13% of TOC and total N, respectively. Dissolved nitrogen(N), mainly present as ammonium, represented 2.40% of the total N. The low aromatic component and large presence of nitrogen(N)-derived compounds suggested that most of the organic carbon(OC) in these organic-rich mineral deposits was derived from microbial cells, although the high average radiocarbon age of about 2900 years may also point to the contribution of aeolian depositions of anthropogenic or natural origin. Elemental composition and the crustal enrichment factor of trace elements in the mineral fraction of the aggregates corroborated the hypothesis that most part of the accumulated material derived from ice meltwater. Some indicators of the colonization of these deposits by microbial communities were also reported, from the abundance of DNA and phylogenetic markers, to the presence of bacterial taxa commonly able to thrive in similar habitats. All these elements suggested that such kind of deposits may have a p

关键词： Glacier foreland Dissolved organic carbon Organic matter q PCR Microbial community Trace elements

A putative plant organelle RNA recognition protein gene is essential for maize kernel development

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Journal of Integrative Plant Biology 2015年第3期57卷 236-246页

作者： Antony M.Chettoor Gibum Yi Elisa Gomez Gregorio Hueros Robert B.Meeley Philip w.Becraft Department of Genetics Development and Cell BiologyIowa State University Carnegie Institution of Science Plant Genomics and Breeding Institute Seoul National University Department of Biotechnology and Biomedicine University of AlcalaUniversity Campus Du Pont Pioneer Department of Agronomy Iowa State University

Basal endosperm transfer layer（BETL） cells are responsible for transferring apoplastic solutes from the maternal pedicel into the endosperm,supplying the grain with compounds required for embryo development and storage reserve ***,we analyze the maize（Zea mays L.） empty pericarp6（emp6） mutant,which causes early arrest in grain *** Emp6 tgene function is required independently in both the embryo and *** emp6 mutant causes a notable effect on the differentiation of BETL cells;the extensive cell wall ingrowths that distinguish BETL cells are diminished and BETL marker gene expression is compromised in mutant *** tagging identified the emp6 locus as encoding a putative plant organelle RNA recognition（PORR） protein,1 of 15 PORR family members in *** emp6 transcript is widely detected in plant tissues with highest Researclevels in embryos and developing ***6-green fluorescent protein（GFP） fusion proteins transiently expressed in Nicotiana benthamiana leaves were targeted specifically to *** results suggest that BETL cell differentiation might be particularly energy intensive,or alternatively,that mitochondria might confer a developmental function.

关键词： Empty pericarp endosperm mitochondria RNA processing transfer cell

Does multiple seed loading in Blue Jays result in selective dispersal of smaller acorns?

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Integrative Zoology 2011年第3期6卷 235-243页

作者： Andrew w.BARTLOw Michael KACHMAR Nathanael LICHTI Robert K.SwIHART Jeffrey A.STRATFORD Michael A.STEELE Department of Biology Wilkes UniversityWilkes BarrePennsylvaniaUSA Department of Forestry and Natural Resources Purdue UniversityWest LafayetteIndianaUSA

Studies from both tropical and temperate systems show that scatter-hoarding rodents selectively disperse larger seeds farther from their source than smaller seeds,potentially increasing seedling establishment in larger-seeded ***-biased dispersal is evident in many oaks(Quercus)and is true both across and within ***,we predict that intraspecifc variation in seed size also influences acorn dispersal by the Blue Jay(Cyanocitta cristata Linnaeus),but in an opposite *** Jays are gape-limited and selectively disperse smaller acorn species(*** oaks[Quercus palustris Münchh]),but often carry several acorns in their crop during a single dispersal *** predict that jays foraging on smaller acorns will load more seeds per trip and disperse seeds to greater distances than when single acorns are carried in the *** test this,we presented free-ranging Blue Jays with pin oak acorns of different sizes over a 2-year *** each of 16 experimental trials,we monitored the birds at a feeding station with remote cameras and determined the number of acorns removed and the distance acorns were dispersed when *** were significantly more likely to engage in multiple seed loading with smaller seeds in both years of the *** the second year,these smaller acorns were dispersed farther than larger acorns,and during the first year,larger acorns were dispersed farther,revealing an inconsistent response to seed size during our *** suggest that in some circumstances,multiple seed loading by Blue Jays may favor dispersal in some plant species.

关键词： acorn dispersal Blue Jays Cyanocitta cristata Quercus seed size

Spatiotemporal dynamics in butterfly hybrid zones

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Insect Science 2024年第2期31卷 328-353页

作者： Ananda R.Pereira Martins Natalie B.warren w.Owen McMillan Rowan D.H.Barrett Redpath Museum McGill University859 Sherbrooke Street WestMontrealQuebecCanada Smithsonian Tropical ResearchInstitute GamboaPanama CityPanama

Evaluating whether hybrid zones are stable or mobile can provide novelinsights for evolution and conservation biology. Butterflies exhibit high sensitivity to envi-ronmental changes and represent an important model system for the study of hybrid zoneorigins and maintenance. Here, we review the literature exploring butterfly hybrid zones,with a special focus on their spatiotemporal dynamics and the potential mechanisms thatcould lead to their movement or stability. we then compare different lines of evidenceused to investigate hybrid zone dynamics and discuss the strengths and weaknesses ofeach approach. Our goal with this review is to reveal general conditions associated withthe stability or mobility of butterfly hybrid zones by synthesizing evidence obtained us-ing different types of data sampled across multiple regions and spatial scales. Finally, wediscuss spatiotemporal dynamics in the context of a speciation/divergence continuum, therelevance of hybrid zones for conservation biology, and recommend key topics for futureinvestigation.

关键词： butterflies human impacts hybrid zones movement spatiotemporaldynamics stability

Catalytic Performance in CO Hydrogenation Over SiO_2-Supported Ru-M (M=Co, Fe,Mo,Ni,Rh,Mn and Cr) Bimetallic Cluster-derived Catalysts

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Science China Chemistry 1993年第2期36卷 151-161页

作者：肖丰收徐如人 Ichikawa Masaru Fukuoka Atsushi Shriver D.F Henderson w 郭燮贤辛勤 Department of Chemistry Jilin University Changchun 130023 PRC Catalysis Research Center Hokkaido University Sapporo 060 Japan Department of Chemistry Northwestern University Evanston IL 60208-3113 USA National Lab. for Catalysis Dalian Institute of Chemical Physics Academia Sinica Dalian 116023 PRC

The bimetallic Ru-M (M=Co,Fe,Ni,Mo, Rh,Cr, Mn) catalysts were prepared from SiO_2-supported bimetallic carbonyl clusters, and it was found that the Ru-Co, Ru-Fe and Ru-Mo bimetallic carbonyl cluster-derived catalysts showed higher activity and selectivity for oxygenates such as C_1-C_5 alcohols in CO hydrogenation,in contrast to catalysts prepared from SiO_2-supported homometallic Ru and Co carbonyl clusters. In situ FT-IR studies revealed that the bands at 1584 and 1555 cm^(-1) species were intermediates to produce methanol and higher oxygenates,and at higher temperatures the 1584 cm^(-1) species could react with alkyl to form 1555 cm^(-1) species. By the surface chemical reaction and the IR study of isotopic molecules,it was suggested that 1584 and 1555 cm^(-1) were assigned to surface formyl and acetyl species.

关键词： bimetallic carbonyl cluster Ru eluster bimetallie eatalyst CO hydrogenation oxygenates IR spectra surface formyl and aeetyl.