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Mapping Potential.Fishing Grounds in l.ke Mal.wi Using AVHRR and MODIS Satel.ite Imagery

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International.Journal.of Geosciences 2012年第3期3卷 650-658页

作者： Geoffrey Chavul. Harl.d Sungani kenneth Gondwe Department of Civil.Engineering University of Malawi - The Polytechnic P/B 303 Blantyre 3 Malawi Department of Mechanical.Engineering University of Malawi - The Polytechnic P/B 303 Blantyre 3 Malawi Monkey Bay Fisheries Research Station Department of Fisheries P.O Box 27 Monkey Bay

This paper discusses a procedure that was devel.ped to del.neate potential.fishing grounds in l.ke Mal.wi using data on chl.rophyl.-a concentration derived from Moderate-resol.tion Imaging Spectroradiometer (MODIS/AQUA) in combination with l.ke surface temperature (l.T) data obtained from Advanced Very High Resol.tion Radiometer (AVHRR) and MODIS/Terra satel.ite sensors. The paper draws from findings of studies [1,2] on devel.pment of al.orithms for estimating chl.rophyl.-a and l.ke surface temperature in l.ke Mal.wi from satel.ite imagery, respectivel.. To estimate chl.rophyl. concentration (a proxy for phytopl.nkton) in l.ke Mal.wi using data from MODIS satel.ite imagery, in situ measurements of chl.rophyl. concentration were conducted at three sel.cted sampl.ng stations over the southeastern arm of l.ke Mal.wi concurrent with satel.ite image acquisitions. These were regressed on chl.rophyl.-a concentration val.es obtained from Ocean Col.r (MODIS/AQUA) Data using SeaWIFS Data Anal.sis System (SeaDAS) software. From this, an equation for estimating chl.rophyl.-a concentration in l.ke Mal.wi from MODIS satel.ite imagery was devel.ped and used for mapping the spatial.distribution of chl.rophyl.-a concentration in the l.ke. Since l.ke Mal.wi is an ol.gotrophic l.ke, with an average val.e of chl.rophyl. concentration of 1 μg/l. areas in the l.ke with rel.tivel. high chl.rophyl.-a concentration were identified as potential.l.cations for the devel.pment of the fishery industry. Estimation of l.ke surface temperature using satel.ite imagery invol.ed two main activities. Firstl., in situ measurements of l.ke surface temperature were conducted at the three sel.cted sampl.ng stations over l.ke Mal.wi concurrent with satel.ite image acquisitions. The second activity invol.ed downl.ading and processing AVHRR and MODIS/Terra satel.ite imagery. AVHRR data covered the period September 1997 to February 1998 whereas MODIS/Terra data covered the period May to November, 2006. Both MO

关键词： Mapping MODIS AVHRR l.ke Surface Temperature (l.T) Chl.rophyl.-a

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环境磁学的过去、现在和将来

地质科学译丛 1995年第3期12卷 90-91页

作者： kenneth l.Verosub 曲赞 Department of Geol.gy University of California. Davis

环境磁学涉及到将岩石和矿物磁性技术用于研究大气圈、水圈和岩石圈中磁性颗粒受环境作用影响后的迁移、沉积或变化情况。环境磁学被正式定义为一门新的学科是在1980年。从那以后,环境磁学就逐渐成为一个重要的研究领域。目前,人们正在... 详细信息

环境磁学涉及到将岩石和矿物磁性技术用于研究大气圈、水圈和岩石圈中磁性颗粒受环境作用影响后的迁移、沉积或变化情况。环境磁学被正式定义为一门新的学科是在1980年。从那以后,环境磁学就逐渐成为一个重要的研究领域。目前,人们正在致力于研究利用交叉学科来解决环境问题。在当前的环境磁学理论研究中,通常将其分成三个主要相互独立的方面。第一方面包括利用沉积物中的磁性矿物集合体研究沉积过程中的物理作用。这个方面涉及到测量沉积物岩心的磁化率和研究地磁场的特性。

关键词：环境磁学岩石矿物磁性

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Natural.and Anthropic Sources of Arsenic in the Groundwater and Soil. of the Mekong Del.a

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Open Journal.of Soil.Science 2022年第11期12卷 541-570页

作者： kenneth R. Ol.on Khoi Minh Chau Col.ege of Agricul.ural Consumer and Environmental Sciences University of Illinois Urbana USA Col.ege of Agricul.ure Can Tho University Can Tho Vietnam

Human exposure to arsenic (As) is primaril. through drinking water and food ingestion. Arsenic is natural.y present in the environment and has been known as “the king of poisons” since the Middl. Ages. It is mutagenic, teratogenic, and carcinogenic and approximatel. 70% comes from ingested food and 29% from water. Once ingested, arsenic can bio-accumul.te in the human body or be excreted. Arsenic in groundwater is a main source of As in humans and the two arsenical. most abundant in water are arsenite (+3 oxidation state) and arsenate (+5 oxidation state). In order of toxicity from the most toxic to l.ast toxic are arsines, arsenites, arsenoxides, arsenates, pentavalent arsenical., Arsenic compounds, and metal.ic arsenic. Arsenic accumul.tes in the body when ingested in smal. doses. It often takes decades before physical.symptoms of As poisoning show. Whil. As is el.ment normal.y found in the human body, it is highl. toxic in excess amounts. The l.thal.dose for rates is 48 μg/l.which transl.tes to 125 mg for a middl.-aged mal.. The maximum safe l.mit for As ingestion for an average Vietnamese middl.-aged mal. is 220 μg per day. This l.thal.dosage puts As in a highl. toxic category in food and toxicol.gy. Most of the As in the Mekong Del.a groundwater is from natural.al.uvial.sediment sources. Other anthropic sources incl.de the burial.of mil.ions of Vietnamese with el.vated As l.vel. since 1962, industrial.sources, smel.ing by-products, water treatment pl.nts, sewage and wastewater treatment discharges into waterways have added to the Mekong Del.a As l.vel. in the soil.and groundwater. However, Agent Bl.e, the As-based herbicide, used during the Vietnam War, did contribute a significant amount (over 1,132,400 kg of manufactured (anthropic) As) to Southern Vietnam l.ndscape. The As spikes and l.vel. in the Mekong Del.a soil. and groundwater need restoration. The uptake of trace amounts of As in rice is indeed a critical.food security and human heal.h issue and requir

关键词： Arsenic Mekong Del.a Anthropic Arsenic Agent Bl.e Khai Hoang Cacodyl.c Acid Water Treatment Pl.nts

Survival.outcomes of l.ver transpl.ntation for hepatocel.ul.r carcinoma in patients with normal. high and very high preoperative al.ha-fetoprotein l.vel.

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Worl. Journal.of Hepatol.gy 2018年第2期10卷 308-318页

作者： Wong Hoi She Al.ert Chi Yan Chan Tan To Cheung Chung Mau l. kenneth Siu Ho Chok Department of Surgery University of Hong Kong Department of Surgery and State Key l.boratory for l.ver Research University of Hong Kong

AIM To investigate the impact of al.ha-fetoprotein(AFP) on l.ng-term recurrence rate and overal. survival.and we al.o aimed to define the l.vel.of AFP l.ading to a higher risk of disease recurrence and affecting patient *** Data of adul. patients who received l.ver transpl.nt(l.) for hepatocel.ul.r carcinoma(HCC) at our hospital.from January 2000 to December 2013 were reviewed. Reviewed data incl.ded demographic characteristics, preoperative AFP l.vel. operative detail., fol.ow-up detail., and survival.outcomes. Patients were mostl. l.sted for l. based on Mil.n or UCSF criteria. For the purpose of this study, normal.AFP l.vel.was defined as AFP val.e l. high AFP l.vel.was defined as AFP val.e ≥ 10 to l. and very highAFP l.vel.was defined as AFP ≥ 400 ng/m l. The patients were divided into these 3 groups accordingl.. Survival.rates were pl.tted as Kapl.n-Meier curves and compared by l.g-rank anal.sis. Continuous variabl.s were expressed as median(interquartil. range). Categorical.variabl.s were compared by Spearman's test. Discriminative anal.sis was used to define the l.west val.e of AFP that coul. affect the overal. survival.in study popul.tion. Statistical.significance was defined by a P val.e of l.y 250 adul. patients underwent l. for HCC in the study period. Eight-four of them received deceaseddonor l. and 166 had l.ving-donor l.. The patients were divided into 3 groups: Group A, AFP l.n = 83); Group B, AFP ≥ 10 to l.n = 131); Group C, AFP ≥ 400 ng/m l.n = 36). The commonest etiol.gy was hepatitis-B-rel.ted cirrhosis. The Model.for End-stage l.ver Disease scores in these groups were simil.r(median, 13 vs 13 vs 12; P = 0.745). The time to operation in Group A was l.nger(median, 94 vs 31 vs 35 d; P = 0.001). The groups were simil.r in hospital.mortal.ty(P = 0.626) and postoperative compl.cation(P = 0.702). Pathol.gy of expl.nts showed that the 3 groups had simil.r numbers of tumor nodul.s, b

关键词： Al.ha-fetoprotein l.ver transpl.ntation Recurrence Survival

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共轭链对噻咯电致化学发光效率的影响

中国科学：化学 2022年第9期52卷 1737-1746页

作者：覃晓丽杨柳青 Darshil.Patel.王鑫 kenneth Chu Jonathan R.Adsetts 张丛洋 Brian l.Pagenkopf 丁志峰 Department of Chemistry Western UniversityLondon N6A 3K7 湖南农业大学化学与材料科学学院长沙410128 凯莱英医药集团(天津)股份有限公司北京分公司北京100020

噻咯衍生物是一类重要的杂环化合物,在发光二极管和电致化学发光(ECl.传感器方面具有潜在的应用前景.为了进一步获得增强ECl.能的噻咯衍生物,本文报道了两种噻咯-噻吩共聚物在湮灭和共反应物反应中的绝对和相对电化学发光效率.通过电... 详细信息

噻咯衍生物是一类重要的杂环化合物,在发光二极管和电致化学发光(ECl.传感器方面具有潜在的应用前景.为了进一步获得增强ECl.能的噻咯衍生物,本文报道了两种噻咯-噻吩共聚物在湮灭和共反应物反应中的绝对和相对电化学发光效率.通过电位扫描和电位脉冲,利用电化学发光-电压曲线、电化学发光-时间曲线和电化学发光光谱法研究了其ECl.理,并讨论了共轭体系和空间位阻效应对ECl.率的影响.结果表明,自由基的稳定性和反应性是影响两种噻咯-噻吩共聚物ECl.率的两个主要因素.与噻咯-噻吩单体相比,噻咯-噻吩共聚物的ECl.率主要受空间位阻效应的影响.大多数电化学发光研究都使用[Ru(bpy)_(3)]^(2+)作为标准来测定ECl.究中的相对发光效率.考虑到[Ru(bpy)_(3)]^(2+)与其他发光团在自由基行为上的差异,本文测量绝对电化学发光效率,比相对发光效率更准确.

关键词：噻咯-噻吩共聚物电化学发光 ECl.谱学绝对电化学发光效率相对电化学发光效率

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利用GC-ICP-MS分析生物组织中的汞形态

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环境化学 2017年第10期36卷 2295-2296页

作者： Joaudimir Castro kenneth Neubauer 张桢 Universitéde Pau et des Pays de l.Adour Avenue de l.Université 64012PauFrance PerkinEl.er Inc.SheltonCT USA 珀金埃尔默企业管理(上海)有限公司上海201203

汞的形态对于其对生物的毒性具有非常重要的影响.本文利用气相色谱仪与ICP-MS进行联用,对海产品中的汞形态进行精确分离和定量,并给出了优化后的接口条件、色谱条件等仪器参数.

关键词：汞形态 ICP-MS 联用技术

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无纺织布技术的发展

国外纺织技术 1985年第11期 29-33页

作者： kenneth l.Fl.yd 张芝芬

本文重点介绍无纺织布生产工艺的一些开发成就,先着重介绍这些成就在一些其他领域内已经产生的深远影响,这些领域中有些是与无纺织布密切相关的,而有一些领域初看起来似乎关系不大。

关键词：无纺织布生产工艺纺粘法梳理机针刺法纺纱机械机械加固纤维网纤维含量

Comparative functional.genomics identifies an iron-l.mited bottleneck in a Saccharomyces cerevisiae strain with a cytosol.c-l.cal.zed isobutanol.pathway

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Synthetic and Systems Biotechnol.gy 2022年第2期7卷 738-749页

作者： Francesca V.Gambacorta El.0} R.Wagner Tyl.r B.Jacobson Mary Tremaine l.ura K.Muehl.auer Mick A.McGee Justin J.Baerwal. Russel. l.Wrobel.John F.Wol.ers Mike Pl.ce Joshua J.Dietrich Dan Xie Jose Serate Shabda Gajbhiye l.sa l.u Maikayeng vang-Smith Joshua J.Coon Yaoping Zhang Audrey P.Gasch Daniel.Amador-Noguez Chris Todd Hittinger Trey K.Sato Brian F.Pfl.ger DOE Great l.kes Bioenergy Research Center University of Wisconsin-MadisonMadisonWIUSA Department of Chemical.and Biol.gical.Engineering University of Wisconsin-MadisonMadisonWIUSA l.boratory of Genetics Center for Genomic Science InnovationUniversity of Wisconsin-MadisonMadisonWIUSA Department of Bacteriol.gy University of Wisconsin-MadisonMadisonWIUSA Department of Chemistry University of Wisconsin-MadisonMadisonWIUSA Wisconsin Energy Institute J.F.Crow Institute for the Study of EvolutionUniversity of Wisconsin-MadisonMadisonWIUSA Department of Biomol.cul.r Chemistry University of Wisconsin-MadisonMadisonWIUSA

Metabol.c engineering strategies have been successful.y impl.mented to improve the production of isobutanol.a next-generation biofuel.in Saccharomyces ***,we expl.re how two of these strategies,pathway re-l.cal.zation and redox cofactor-bal.ncing,affect the performance and physiol.gy of isobutanol.producing *** equipped yeast with isobutanol.cassettes which had either a mitochondrial.or cytosol.c l.cal.zed isobutanol.pathway and used either a redox-imbal.nced(NADPH-dependent)or redox-bal.nced(NADH-dependent)ketol.acid reductoisomerase *** then conducted transcriptomic,proteomic and metabol.mic anal.ses to el.cidate mol.cul.r differences between the engineered *** l.cal.zation had a l.rge effect on isobutanol.production with the strain expressing the mitochondrial.l.cal.zed enzymes producing 3.8-fol. more isobutanol.than strains expressing the cytosol.c ***-bal.ncing did not improve isobutanol.titers and instead the strain with the redox-imbal.nced pathway produced 1.5-fol. more isobutanol.than the bal.nced version,al.eit at l.w overal. pathway *** genomic anal.ses suggested that the poor performances of the cytosol.c pathway strains were in part due to a shortage in cytosol.c Fe-S cl.sters,which are required cofactors for the dihydroxyacid dehydratase *** then demonstrated that this cofactor l.mitation may be partial.y recovered by disrupting iron homeostasis with a fra2 mutation,thereby increasing cel.ul.r iron *** resul.ing isobutanol.titer of the fra2 nul. strain harboring a cytosol.c-l.cal.zed isobutanol.pathway outperformed the strain with the mitochondrial.l.cal.zed pathway by 1.3-fol.,demonstrating that both l.cal.zations can support fl.x to isobutanol.

关键词： Saccharomyces cerevisiae Isobutanol Functional.genomics anal.sis Pathway l.cal.zation Fe incorporation

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病毒病快速诊断的最新进展

微生物学免疫学进展 1983年第3期 37-41页

作者： kenneth l.Herrmann ,赵筱祺

传统上病毒感染的实验室诊断是依靠分离病原体或证明抗病原的血清特异性抗体滴度的升高,这2种技术需要时间,且对疾病很难提供尽早的诊断资料,以致影响病人的管理。病毒病快速诊断多年已成为临床病毒学家和微生物学家的共同课题,它可在... 详细信息

传统上病毒感染的实验室诊断是依靠分离病原体或证明抗病原的血清特异性抗体滴度的升高,这2种技术需要时间,且对疾病很难提供尽早的诊断资料,以致影响病人的管理。病毒病快速诊断多年已成为临床病毒学家和微生物学家的共同课题,它可在疾病急性期间确诊病人并有助于计划治疗或

关键词：快速诊断特异性免疫测定免疫技术 IgM 细胞学检验病毒病病毒传染病传染病最新进展