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Precipitation variation in the northeastern Tibetan Plateau recorded by the tree rings since 850 AD and its relevance to the Northern Hemisphere temperature

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Science China Earth Sciences 2006年第4期49卷 408-420页

作者： john k. kutzbach Center for Climatic Research University of Wisconsin-Madison Madison 53706 USA

Three well-dated Sabina Przewalsk.i ring-width chronologies from Dulan, China, have been used to reconstruct annual precipitation (from prior July to current June) variations on the northeast Tibetan Plateau since 850 AD. The reconstructions account of the instrumentally recorded precipitation variance are: 54.7% for the period of 1385-2000AD; 50.5% for 1099-1384AD and 45.7% for 850-1098AD. On the millenary scale, the precipitation variation over this region displays “W” shape, which has three peak. and two valleys. The precipitation is low during 1571-1879 AD, and high during 1880-2000 AD. 1900-2000 AD is the century with the highest precipitation over the northeast Tibetan Plateau in the last 1000 years, and 1962-2000 is the period with the highest pre- cipitation, and the highest variability of precipitation as well in the last 1000 years. The reconstructed series also reveals that the variability of annual precipitation is large when the precipitation is more, and contrarily, variability is small when the precipitation is low. With the temperature increasing obvi- ously in the 20th century, the precipitation in the study region significantly increased too, the variability of precipitation became larger, and drought and flooding occurred more frequently. The yearly tree-ring width (high frequency signal) series in this region reflects the local annually precipitation variation. However, the series with 40-year moving average (low frequency signal) cor- responds to the Northern Hemisphere temperature variations on the decadal to centurial scale. It correlates significantly with seven temperature curves of the Northern Hemisphere in the different time spans. For example, the correlation coefficients with the most temperature curves are around 0.9 during the period of 1852-1982 AD. In general, the temperature and the precipitation change syn- chronously in the Dulan region. It means that low temperature corresponds to low precipitation, andvice versa. This relations

关键词： Dulan China, Sabina Przewalsk.i, annual precipitation, the Northern Hemisphere temperature.

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Hydrogenic Donor in a Spherical Quantum Dot with Different Confinements

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Chinese Physics Letters 2009年第8期26卷 309-312页

作者： A. john Peter k. Navaneethak.ishnan Govt. Arts College Melur-625 106 Madurad India Madurai k.maraj-University Madurai-625 021 India

Binding energies of a hydrogenic donor in a spherical GaAs quantum dot surrounded by Ga1-xA4xAs matrix are calculated. The results are presented for realistie barrier heights corresponding to different values of x （x 〈 0.4）. The calculations are performed under two different conditions：（i） a spherical dot with square well confinement and （ii） a dot with parabolic potential well confinement. The results show that （i） the donor ionization energies are always higher under parabolic confinement as compared to a dot of the same radius under square well confinement and （ii） the oscillator strengths coupling ground state with excited states are two orders larger under parabolic confinement. Our results are in agreement with the results of other researchers.

关键词： ELECTRON donor-acceptor complexes QUANTUM dots BINDING energy OSCILLATOR strengths PLASMA confinement QUANTUM wells GALLIUM arsenide semiconductors

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Vasectomy by epithelial curettage without suture or cautery： a pilot study in humans

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Asian Journal of Andrology 2010年第3期12卷 315-321,I0008页

作者： john k. Amory john W. Jessen Charles Muller Richard E. Berger Department of Medicine Center for Research in Reproduction and Contraception University of Washington School of Medicine Seattle WA 98195 USA private Practice Dentistry Seattle WA 98195 USA Department of Urology University of Washington School of Medicine Seattle WA 98195 USA

Curettage of the epithelium of the vas deferens might be a safe and effective method of male sterilization. We conducted a pilot study of vasectomy by epithelial curettage with a novel microcurette called the Vas-X in 12 normal men requesting elective sterilization. Seminal fluid analysis was obtained monthly after the procedure for 6 months. Pain was assessed by questionnaire. Three months after the procedure, all men attained sperm concentrations of less than 0.2 million sperm per mL, and seven were azoospermic. Post-procedural pain was minimal. Nine men ultimately achieved and maintained azoospermia; however, 4 to 6 months after the procedure, sperm concentrations increased in three of the 12 subjects, necessitating repeat vasectomy. Microscopic examination of the vas deferens from these failures revealed re-canalization. Vasectomy by epithelial curettage can result in effective sterilization; however, 1/4 of the subjects were not effectively sterilized by the procedure due to re-canalization of the vas deferens. Epithelial curettage will require further refinement to determine if it is a viable form of vasectomy.

关键词： male contraception male sterilization re-canalization spermatogenesis vas deferens vasectomy failure

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Phyllofenone A, a New Scalarane Sesterterpene from the Sponge Phyllospongia Foliascens(Pallas)

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Chemical Research in Chinese Universities 1991年第2期7卷 100-106页

作者： john k. Snyder Department of Chemistry Boston University Boston USAhe present paper covers the structure of a new sesterterpene phyllofenone A(1) isolated from the South China Sea sponge Phyllospongia foliascens. Phyllofenone A is a member of the scalarane class of sesterterpenes with a (C-20 C-24)-bishomo-(C-25)-nortetra-cyclic skeleton. The structure charcterization was based on one- and two-dimensional NMR and mass spectroscopy with the assistance of molecular modeling. Phyllofenone A shows weak antifungal activity against Candida pseudotropicalis.

The present paper covers the structure of a new sesterterpene, phyllofenone A(1) , isolated from the South China Sea sponge Phyllospongia foliascens. Phyllofenone A is a member of the scalarane class of sesterterpenes with a (C-20, C-24)-bishomo-(C-25)-nortetra-cyclic sk.leton. The structure charcterization was based on one- and two-dimensional NMR and mass spectroscopy with the assistance of molecular modeling. Phyllofenone A shows weak.antifungal activity against Candida pseudotropicalis.

关键词： Sponge Sesterterpene Selective INEPT 2D NMR

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Analyzing biases of nitrogen contents and δ^(15)N values arising from acidified marine sediments with different CaCO_3 concentrations

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Acta Oceanologica Sinica 2018年第8期37卷 1-5页

作者： PENG Yajun LIU Dongyan WANG Yujue RICHARD Pierre k.ESING john k. k.y Laboratory of Coastal Zone Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research Chinese Academy of Sciences School of Management Science Guizhou University of Finance and Economics State k.y Laboratory of Estuarine and Coastal Research East China Normal University Littoral Environment et Sociétés UMR 7266 CNRS-Université de La Rochelle CSIRO Oceans and Atmosphere and University of Western Australia Oceans Institute Indian Ocean Marine Research Centre

In some studies, the researchers pretreated and measured organic carbon, nitrogen and their isotopes（δ^（13）C and δ^（15）N） of marine sediment together, to save costs and resources of analysis. However, the procedure of acidification to remove inorganic carbon for analysing δ^（13）C can affect the values of nitrogen and δ^（15）N, and the biases vary a lot depending on the CaCO_3 contents of sediments. In this study, the biases of total nitrogen（TN）and δ^（15）N values arising from acidified sediments were compared between the CaCO_3-poor（1%–16%） and CaCO_3-rich（20%–40%） samples. TN and δ^（15）N values were altered during acid treatment（without centrifugation） that possibly led to N-containing compounds volatilization. For CaCO_3-poor samples, acidification led to a range of 0%–40% TN losses and 0‰–2‰ shift in δ^（15）N values; and 10%–60% TN losses and 1‰–14‰ shift in δ^（15）N values for CaCO_3-rich samples. The biases from most samples exceeded the precision of the instrument（0.002% for TN and 0.08‰ for δ^（15）N）, and high biases could mislead our judgment for the environmental implication of the data. Thus,avoiding co-analysis of organic carbon, nitrogen and their isotopes（δ^（13）C and δ^（15）N） in sediments, even for CaCO_3-poor marine sediments, is necessary.

关键词： stable isotope nitrogen nitrogen CaCO3 acidification marine sediment

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Integrative behavioral ecotoxicology： bringing together fields to establish new insight to behavioral ecology, toxicology, and conservation

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Current Zoology 2017年第2期63卷 185-194页

作者： Elizabeth k. PETERSON David B. BUCHWALTER Jacob L. k.RBY Matthew k. LEFAUVE Claire W. VARIAN-RAMOS john R SWADDLE Department of Biological Sciences State University of New York-Albany Albany NY 12222 USA Department of Biological Sciences North Carolina State University Raleigh NC 27695 USA Department of Biology University of South Dakota Vermillion SD 57069 USA Department of Biological Sciences George Washington University Washington DC 20052 USA Department of Biology Colorado State University-Pueblo Pueblo CO 81001 USA Biology Department Institute for Integrative Bird Behavior Studies College of William & Mary Williamsburg VA 23187-8795 USA

The fields of behavioral ecology, conservation science, and environmental toxicology individually aim to protect and manage the conservation of wildlife in response to anthropogenic stressors, including widespread anthropogenic pollution. Although great emphasis in the field of toxicology has been placed on understanding how single pollutants affect survival, a comprehensive, interdis- ciplinary approach that includes behavioral ecology is essential to address how anthropogenic compounds are a risk.for the survival of species and populations in an increasingly polluted world. We provide an integrative framework.for behavioral ecotoxicology using Tinbergen＇s four postu- lates （causation and mechanism, development and ontogeny, function and fitness, and evolution- ary history and phylogenetic patterns）. The aims of this review are： 1） to promote an integrative view and re-define the field of integrative behavioral ecotoxicology; 2） to demonstrate how study- ing ecotoxicology can promote behavior research; and 3） to identify areas of behavioral ecotoxicol- ogy that require further attention to promote the integration and growth of the field.

关键词： animal behavior behavioral ecology conservation phylogenetic pollution toxicology.

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Wavelet pack.t-based identification of complex oscillation in biological signals

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仪器仪表学报 2008年第2期29卷 225-232页

作者： Zhang Shuqing Sarah k. Spurgeon Zhang Liguo Jin Mei john A. Twiddle Femando S. Schlindwein College of Electric Engineering Yanshan University Qinhuangdao 066004 China Department of Engineering University of Leicester University Road Leicester LE1 7RH UK

Owing to the intrinsic nonlinearities of the system,a contracting mechanism,such as myogenic response,may induce different oscillatory *** specialists discussed the relations of oscillatory patterns with intrinsic control system or some pathological condition,but there is no single,well-defined criterion to achieve the identification of regular,stochastic,and chaotic *** this paper,we focus on the Mallat algorithm of wavelet pack.t and use it in the identification of the regular periodic,stochastic,and chaotic *** to the specific frequency configuration of the chaos activity,we select proper layers of decomposition of wavelet pack.t and did fine segments to the frequency of *** frequency band of energy convergence could be *** signal of periodic,stochastic,and chaotic could be distinguished depending on *** experiment is given to show its *** on 12 babies' lung data have been *** identification by means of wavelet pack.t could support the cardiologist or cerebral specialist to do more observation and deeper analysis to physic signals.

关键词：复振荡生物信号鉴别模式不规则波动微波

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pH modeling for maximum dissolved organic matter removal by enhanced coagulation

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Journal of Environmental Sciences 2012年第2期24卷 276-283页

作者： Jiank.n Xie Dongsheng Wang john van Leeuwen Yanmei Zhao Linan Xing Christopher W. k. Chow State k.y Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China SA Water Centre for Water Management and Reuse NBE Universit of South Australia Australia Australian Water Quality Centre SA Water 250 Victoria Square Adelaide SA 5000 Australia

Correlations between raw water characteristics and pH after enhanced coagulation to maximize dissolved organic matter（DOM） removal using four typical coagulants（FeCl3,Al2（SO4）3,polyaluminum chloride（PACl） and high performance polyaluminum chloride（HPAC）） without pH control were *** correlations were analyzed on the basis of the raw water quality and the chemical and physical fractionations of DOM of thirteen Chinese source waters over three *** was found that the final pH after enhanced coagulation for each of the four coagulants was in？uenced by the content of removable DOM（*** and higher apparent molecular weight（AMW） DOM）,the alk.linity and the initial pH of raw water.A set of feed-forward semi-empirical models relating the final pH after enhanced coagulation for each of the four coagulants with the raw water characteristics were developed and optimized based on correlation *** established models were preliminarily validated for prediction purposes,and it was found that the deviation between the predicted data and actual data was *** result demonstrated the potential for the application of these models in practical operation of drink.ng water treatment plants.

关键词： enhanced coagulation modeling DOM fractionation pH control

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Resurgence of the cotton bollworm Helicoverpa armigera in northern Greece associated with insecticide resistance

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Insect Science 2013年第4期20卷 505-512页

作者： George k. Mironidis Despina k.pantaidak. Maria Bentila Evangelia Morou M. Savopoulou-Soultani john Vontas Laboratory of Applied Zoology and Parasitology Faculty of Agriculture Aristotle University of Thessaloniki Thessaloniki Faculty of Applied Biology and Biotechnology Department of Biology University of Crete Heraklion Greece

Helicoverpa armigera has been controlled effectively with chemical insec- ticides in the major cotton crop production areas of northern Greece for many years. However, a resurgence of the pest was observed in 2010, which significantly affected crop production. During a 4-year survey （2007-2010）, we examined the insecticide re- sistance status of 1-1. armigera populations from two major and representative cotton production areas in northern Greece against seven insecticides （chlorpyrifos, diazinon, methomyl, alpha-cypermethrin, cypermethrin, gamma-cyhalothrin and endosulfan）. Full dose-response bioassays on third instar larvae were performed by topical application. Lethal doses at 50% were estimated by probit analysis and resistance factors （RF） were calculated, compared to a susceptible laboratory reference stra^a. Resistance levels were relatively moderate until 2009, with resistance ratios below 10-fold for organophosphates and carbamates and up to 16-fold for the pyrethroid alpha-cypermethrin. However, resis- tance rose to 46- and 81-fold for chlorpyrifos and alpha-cypermethrin, respectively in 2010, when the resurgence of the pest was observed. None of the k.own pyrethroid resistance mutations were found in the pyrethroid-resistant insects. The possible association between resistance and H. armigera resurgence in Greece is discussed.

关键词： bioassay carbamates cotton field endosulfan organophospates pyrethroids

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Characteristics, development and utilization of geothermal resources- a Nordic perspective

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Episodes 2008年第1期31卷 140-147页

作者： john W. Lund Leif Bjelm Gordon Bloomquist Anette k. Mortensen Geo-Heat Center Oregon Institute of Technology Klamath Falls Oregon USA. Engineering Geology Department Lund University Lund Sweden. WSU Energy Program Washington State University Olympia Washington USA. Iceland GeoSurvey Reykjavfk Iceland.

Geothermal energy is classified as a renewable energy source and it utilizes the heat generated in the earth primarily from the natural radioactive decay of isotopes of uranium, thorium and potassium. Heat is extracted from the earth to generate geothermal energy via a carrier, usually water occurring either in the liquid or steam phase. In the late 19th century and the early 20th century, the first developments of geothermal resources for power generation and household heating got underway successfully. Many of these geothermal fields are still being utilized today, proving their sustainability. Today geothermal energy is being utilized in more than 72 countries around the world and of the Nordic countries Iceland and Sweden have been in the forefront in each of their respective fields. While geothermal heat pumps are widely used for space heating in Sweden, geothermal energy covers 55% of the primary energy consumption in Iceland where it is used for space heating, power generation and industrial purposes. Future developments aim at expanding the range of viable geothermal resources by improving the capabilities to generate electricity from geothermal resources at temperatures as low as 100℃, as well as developing geothermal resources where water needs to be introduced, so-called hot dry rock.resources. But the biggest expansion is expected to continue to be in the installations of geothermal heat pumps.

关键词：地热资源资源利用资源开发合理利用北欧地区

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