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Differential responses of carbon and water vapor fluxes to climate among evergreen needleleaf forests in the USA

ecological Processes 2016年第1期5卷 91-107页

作者： Pradeep Wagle Xiangming Xiao Thomas e.Kolb beverly e.law Sonia Wharton Russell K.Monson Jiquan Chen Peter D.Blanken Kimberly A.Novick Sabina Dore Asko Noormets Prasanna H.Gowda Department of Microbiology and Plant Biology Center for Spatial AnalysisUniversity of OklahomaNormanOK 73019USA Institute of Biodiversity Science Fudan UniversityShanghai 200433China School of Forestry Northern Arizona UniversitylagstaffAZ 86011USA Department of Forest ecosystems and Society Oregon State UniversityCorvallisOR 97331USA Atmospheric Earth and Energy DivisionLawrence Livermore National LaboratoryLivermoreCA 94550USA School of Natural Resources and the environment and Laboratory of Tree Ring Research University of ArizonaTucsonAZ 85711USA Department of Geography Michigan State UniversityEast LansingMI 48824USA Department of Geography University of ColoradoBoulderCO 80309USA School of Public and environmental Affairs Indiana University-BloomingtonBloomingtonIN 47405USA Department of environmental Science Policyand ManagementUniversity of California BerkeleyBerkeleyCA 94702USA Department of Forestry and environmental Resources North Carolina State UniversityRaleighNC 27695USA USDA-ARS Grazinglands Research Laboratory El RenoOK 73036USA

Introduction:Understanding the differences in carbon and water vapor fluxes of spatially distributed evergreen needleleaf forests(eNFs)is crucial for accurately estimating regional or global carbon and water budgets and when predicting the responses of eNFs to current and future ***:We compared the fluxes of ten AmeriFlux eNF sites to investigate cross-site variability in net ecosystem exchange of carbon(Nee),gross primary production(GPP),and evapotranspiration(eT).We used wavelet cross-correlation analysis to examine responses of Nee and eT to common climatic drivers over multiple timescales and also determined optimum values of air temperature(T_(a))and vapor pressure deficit(VPD)for Nee and ***:We found larger differences in the Nee spectra than in the eT spectra across sites,demonstrating that spatial(site-to-site)variability was larger for Nee than for *** Nee and eT were decoupled differently across eNF sites because the wavelet cospectra between eT and climate variables were similar at all sites,while the wavelet cospectra between Nee and climate variables were higher(i.e.,closer coupling between Nee and climatic drivers)in semi-arid and Mediterranean sites than in other *** water use efficiency(eWUe)based on annual GPP/eT ranged from 1.3±0.18 to 4.08±0.62 g C mm^(−1) eT,while eWUe based on annual net ecosystem production(NeP)/eT ranged from 0.06±0.04 to 1.02±0.16 g C mm^(−1) eT)among *** of Nee and eT to T_(a) varied across climatic *** particular,for eNF sites in semi-arid and Mediterranean climates,the maximum Nee and eT occurred at lower ranges of T_(a) than in sites with warm and humid *** optimum T_(a) and VPD values were higher for eT than for Nee,and eT was less sensitive to high values of T_(a) and ***:Large spatial variability in carbon and water vapor fluxes among eNFs and large variations in responses of Nee and eT to major climate variables among climatic zones necessitate sub-

关键词： Drought ecosystem water use efficiency Net ecosystem CO_(2)exchange Spatial variability Wavelet cross-correlation analysis

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Dynamics of carbon stocks in soils and detritus across chronosequences of different forest types in the Pacific Northwest,USA

Dynamics of carbon stocks in soils and detritus across chron...

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“全国第五届青年植物生态学学术研讨会”暨“第二届植物生理生态学学术研讨会”

作者： OSBeRT J.SUN JOHN CAMPBeLL beverly e.law VeRNON WOLF Laboratory of Quantitative Vegetation ecology Institute of Botanythe Chinese Academy of Sciences Beijing 100093 China Department of Forest Science College of Forestry Oregon State UniversityCorvallisOR 97331 USA

We investigated variation in carbon stock in soils and detritus (forest floor and woody debris) in chronosequences that represent the range of forest types in the US Pacific Northwest Stands range in age from 600 years. Soil carbon, to a depth of 100cm, was highest in coastal Sitka spruce/western hemlock forests (36 ±10kgCm-2) and lowest in semiarid ponderosa pine forests (7 ±10kg Cm-2). Forests distributed across the Cascade Mountains had intermediate values between 10 and 25kg Cm-2. Soil carbon stocks were best described as a linear function of net primary productivity (r2 = 0.52), annual precipitation (r2 = 0.51), and a power function of forest floor mean residence time (r2 = 0.67). The highest rates of soil and detritus carbon turnover were recorded on mesic sites of Douglas-fir/western hemlock forests in the Cascade Mountains with lower rates in wetter and drier habitats, similar to the pattern of site productivity. The relative contribution of soil and detritus carbon to total ecosystem carbon decreased as a negative exponential function of stand age to a value of -35% between 150 and 200 years across the forest types. These age-dependent trends in the portioning of carbon between biomass and necromass were not different among forest types. Model estimates of soil carbon storage based on decomposition of legacy carbon and carbon accumulation following stand-replacing disturbance showed that soil carbon storage reached an asymptote between 150 and 200 years, which has significant implications to modeling carbon dynamics of the temperate coniferous forests following a stand-replacing disturbance.

关键词： carbon stock chronosequence climate disturbance forest ecosystem soil carbon

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Distinct Global Patterns of Strong Positive and Negative Shifts of Seasons over the Last 6 Decades

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Atmospheric and Climate Sciences 2012年第1期2卷 76-88页

作者： Andres Schmidt beverly e. law Chad Hanson Otto Klemm 不详

Alterations of annual temperature cycles have profound implications on how the planet responds to global climate change. In this study, a high resolution global analysis of temperature cycle shifts and their development over time is presented. We show that over the last 63 years, phase shifts in the annual near surface temperature cycle exhibit large spatiotemporal variability. The calculated phase shifts comprise earlier onsets of seasons as well as delays with similar frequencies, depending on location. From 1978 to 2010 eastern europe experienced an advanced annual cycle of near-surface temperature of 3.2 days while eastern Australia shows an opposite shift towards later seasons of 3.5 days in comparison to the preceding 30-year period from 1948 to 1977. The largest phase shifts of –5.5 days toward earlier seasons over land were found in Belarus and Northwest Russia. For the first time the developments of seasonal temperature shifts were generalized for large areas by using self-organizing feature map neural networks resulting into 4 significant global trends. The temperature phase shifts are also shown to have strong correlations with the timing of shrub foliation observed at 57 phenological stations across the USA. The findings have far-reaching, yet regionally distinct consequences on agriculture, animal life cycles, plant phenology, and regional weather phenomena that change with annual temperature cycles.

关键词： Climate Change Temperature Phase Shift Neural Networks Phenology Near-Surface Temperature

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Do statins reduce hepatitis C RNA titers during routine clinical use?

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World Journal of Gastroenterology 2009年第40期15卷 5020-5027页

作者： Kimberly A Forde Connie.law Rose O’Flynn David e Kaplan Philadelphia Veterans Administration Medical Center Department of Medicine Division of GastroenterologyUniversity of Pennsylvania Department of Pharmacy Philadelphia Veterans Administration Medical Center

AIM: To compare hepatitis C virus (HCV) titers in patients with chronic hepatitis C with and without exposure to 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins).MeTHODS: Medical records were reviewed for 6463 patients with documented HCV infection at a single center between March 2004 and September 2006. Patients with confi rmed viremia and meeting inclusion criteria were assigned to one of three groups: Group A (n = 50), dyslipidemic patients with statin usage during HCV RNA polymerase chain reaction (PCR) determination; Group B (n = 49), dyslipidemic patients with prior or future statin usage but not at the time of HCV RNA PCR determination; and Group C (n = 102), patients without statin usage during the study period. The primary analysis explored the effect of statin therapy on HCV viremia. Secondary analyses assessed class effect, dose response, and effect of other lipid-lowering therapies on HCV viral ***: Median HCV RNA titers did not signif icantly differ among the three groups (Group A: 4 550 000 IU/mL, Group B: 2 850 000 IU/mL, Group C: 3 055 000 IU/mL).For those subjects with longitudinal assessment of HCV viremia prior to and while on statins, there were no signif icant differences between pre- and post-HCV viral titers. Additionally, no differences in HCV titers were observed at any dose level of the most prescribed statin, simvastatin. However, hypertriglyceridemia independently correlated with HCV titers, and niacin exposure was associated with signif icantly lower viral titers (P ere was no apparent effect of statins on HCV viral replication in this analysis. Further investigation is warranted to explore the possible antiviral properties of triglyceride-lowering agents and their potential role as adjuncts to standard HCV therapy.

关键词： Hepatitis C 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor Statins Geranylgeranyl Prenylation

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Osmotic concentration of succinic acid by forward osmosis:Influence of feed solution pH and evaluation of seawater as draw solution

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Chinese Journal of Chemical engineering 2018年第5期26卷 976-983页

作者： Jeng Yih law Abdul Wahab Mohammad Department of Chemical and Process engineering Faculty of Engineering and Built Environment Universiti Kebangsaan Malaysia Section of Chemical engineering Technology Universiti Kuala Lumpur Malaysian Institute of Chemical & Bioengineering Technology

In this study, we investigated the essential role of feed solution pH so as to gain insights into the transport mechanisms of succinic acid concentration by osmotically-driven forward osmosis （FO） process. FO performances including water flux and bidirectional transport of succinate and chloride anions were systematically examined using cellulose triacetate-based FO membrane. Additionally, real seawater was explored as draw solution. experimental results revealed that the pH-dependent speciation of succinic acid can affect the FO performances. Ionization of succinic acid at higher solution pH enhanced the osmotic pressure of feed solution, thus leading to lower water flux performance. A strong effect was pointed out on the succinate rejection for which nearly 100% rejections were achieved at pH above its pKa2 value. The rejection of succinate increased in the following order of chemical form： C2H4C2O4H2 〈 C2H4C2OH- 〈 C2H4C2O24-. With real seawater as the draw solution, low to moderate water fluxes （〈4 L. m- 2. h- 1 ） were observed. The divalent succinate anion was highly retained in the feed side despite differences in the succinic acid feed concentration at pH of approximately 6.90.

关键词： Forward osmosis Succinic acid pH Transport mechanism Seawater

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Stem Cell Niche,the Microenvironment and Immunological Crosstalk

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Cellular & Molecular Immunology 2008年第2期5卷 107-112页

作者： law Sujata S.Chaudhuri Stem Cell Research and Application Unit Department of Biochemistry and Medical BiotechnologySchool of Tropical MedicineC R AvenueKolkata 700073India

The concept of stem cells, their physiological existence, the intricate anatomical localization, the known and the unknown functions, and their exclusive utility for the purpose of regenerative medicine, are all now encompassed within an emergent question, ＇how compatible these cells are immunologically？＇ Indeed, the medical aspects of stem cells are dependent on a large number of queries based on the basic properties of the cells. It has greatly been emphasized to probe into the basic research on stem cells before any successful therapeutic attempts are made. One of the intricate aspects of the adult stem cells is its immunological behavior in relation to the microenvironmental associates, the stromal cells in the presence of a suitable target. Cellular ＆ Molecular Immunology.

关键词： stem cell niche stromal immunology

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Historical imaginaries, historic urban branding, and the local state in China: rejuvenation discourse, manufactured heritage and simulacrascapes

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Built Heritage 2023年第1期7卷 76-87页

作者： Andrew Malcolm law School of Architecture Planning and LandscapeNewcastle UniversityNewcastleUK

This intervention examines the extant literature on historical imaginaries and historic urban branding in *** suggests that while research in this field has increasingly moved away from an economic(or an implicit neo-Marxist)model,there is still a lack of research on the role of broader cultural and state led discourses of nationalism in the construction of historic urban imaginaries and historic urban branding within Chinese *** unpacking one nationalistic discourse a-narrative of rejuvenation-this article argues that more needs to be done to examine the role of these themes in the construction of historical imaginaries at the level of the local state(including related state networks of developers,retailers,tourist officials,town planners,architects,and designers).It is suggested that an analysis of these discourses and imaginaries is important if we are:1)to appreciate the role of these themes in the construction and/or the reconfiguration of existing or emerging historic brands within Chinese cities;2)to comprehend the construction of'authorised heritage discourses,(AHDs)practices and materialities at the level of the local state;3)to understand the politics of the past(including the uses of history,memory,nostalgia,and heritage)at the level of the local state;4)to be aware of the way in which these themes inform the preservation,conservation,and/or the demolition of heritage space at the level of the local state;5)to recognise the manufacture of'heritage'or simulacrascapes within Chinese cities.

关键词： rejuvenation historical urban imaginaries historical urban branding built heritage simulacrascapes

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南非洲的鼻咽癌——Peter Clifford先生鼻咽癌研究成果回顾

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癌症 2009年第8期28卷 785-790页

作者： beverly e.Griffin Viral Oncology Unit Section of Infectious Diseases Division of Medicine Imperial College at St. Mary's Norfolk Place London W21PG U.K

低分化鼻咽癌(nasopharyngeal carcinoma,NPC)是亚洲某些地区的主要恶性肿瘤,也存在于非洲,尤其是在拥有大量阿拉伯人口的北非,以及在东非"热点"区域的非洲"土著"中。本文主要讨论后者,爱尔兰裔外科医生Peter Clifford在20世纪六七十年... 详细信息

低分化鼻咽癌(nasopharyngeal carcinoma,NPC)是亚洲某些地区的主要恶性肿瘤,也存在于非洲,尤其是在拥有大量阿拉伯人口的北非,以及在东非"热点"区域的非洲"土著"中。本文主要讨论后者,爱尔兰裔外科医生Peter Clifford在20世纪六七十年代对撒哈拉以南非洲"土著"中的鼻咽癌进行过深入研究,从他发表的著作来看,他影响并帮助确定了肯尼亚的头颈部癌症分布地域。他还在非洲儿童恶性肿瘤——伯基特淋巴瘤(Burkitt's lymphoma,BL)方面做出了先驱性的工作。最终确认BL和鼻咽癌都与人疱疹eB病毒(epstein-Barr virus,eBV)有关。本文作为对Peter Clifford先生的纪念,主要介绍他在鼻咽癌方面的贡献,是他第一次明确了鼻咽癌在肯尼亚高原的"热点"地区,研究了在没有放疗的条件下如何更好地治疗鼻咽癌,分析了肯尼亚人群中可能存在的鼻咽癌诱发因素,最终确定了鼻咽癌细胞和eBV的相互作用机制。Peter Clifford的先驱性工作由于意外事故而缩短。虽然在东非以外,他在鼻咽癌研究领域还是个"无名英雄",但是他的影响仍然是巨大的。这些都需要发扬和重新审视。

关键词：头颈部肿瘤鼻咽癌伯基特淋巴瘤 eB病毒鼻咽癌诱发因素肯尼亚人

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Interactions between maternal parity and feed additives drive the composition of pig gut microbiomes in the post‑weaning period

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1241-1257页

作者： Kayla law eduardo Rosa Medina Garcia Chad Hastad Deborah Murray Pedro e.Urriola Andres Gomez Department of Animal Science University of Minnesota1364 Eckles AvenueSaint PaulMN 55108USA New Fashion Pork 164 Industrial ParkwayJacksonMN 56143USA

Background Nursery pigs undergo stressors in the post-weaning period that result in production and welfare *** challenges disproportionately impact the offspring of primiparous sows compared to those of mul-tiparous *** is known regarding potential interactions between parity and feed additives in the post-weaning period and their effects on nursery pig ***,the objective of this study was to investigate the effects of maternal parity on sow and offspring microbiomes and the influence of sow parity on pig fecal microbi-ome and performance in response to a prebiotic *** weaning,piglets were allotted into three treat-ment groups:a standard nursery diet including pharmacological doses of Zn and Cu(Con),a group fed a commercial prebiotic only(Preb)based on an Aspergillus oryzae fermentation extract,and a group fed the same prebiotic plus Zn and Cu(Preb+ZnCu).Results Although there were no differences in vaginal microbiome composition between primiparous and mul-tiparous sows,fecal microbiome composition was different(R^(2)=0.02,P=0.03).The fecal microbiomes of primiparous offspring displayed significantly higher bacterial diversity compared to multiparous offspring at d 0 and d 21 post-weaning(Perences in community composition observed at d 21(R^(2)=0.03,P=0.04).When analyzing the effects of maternal parity within each treatment,only the Preb diet triggered significant microbiome distinc-tions between primiparous and multiparous offspring(d 21:R^(2)=0.13,P=0.01;d 42:R^(2)=0.19,P=0.001).Composi-tional differences in pig fecal microbiomes between treatments were observed only at d 21(R^(2)=0.12,P=0.001).Pigs in the Con group gained significantly more weight throughout the nursery period when compared to those in the Preb+ZnCu *** Nursery pig gut microbiome composition was influenced by supplementation with an Aspergillus oryzae fermentation extract,with varying effects on performance

关键词： Aspergillus prebiotic Copper Feed additives Maternal Nursery pig microbiome Parity Swine microbiome Trace minerals Zinc

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The dispersion of surface contaminants by Stokes drift in random waves

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Acta Oceanologica Sinica 2018年第7期37卷 55-61页

作者： HUANG Guoxing law Wing-Keung Adrian State Key Laboratory of Coastal and Offshore engineering Dalian University of Technology Dalian 116024 China State Key Laboratory of Hydrology Water Resources and Hydraulics Engineering Nanjing 210029 China School of Civil and environmental engineering Nanyang Technological University Singapore 639798 Singapore

Contaminants that are floating on the surface of the ocean are subjected to the action of random *** the literature,it has been asserted by researchers that the random wave action will lead to a dispersion mechanism through the induced Stokes drift,and that this dispersion mechanism may have the same order of significance comparable with the others means due to tidal currents and *** is investigated whether or not surface floating substances will disperse in the random wave environment due to the induced Stokes *** analytical derivation is first performed to obtain the drift velocity under the random *** the analysis,it is shown that the drift velocity is a time-independent value that does not possess any fluctuation given a specific wave energy ***,the random wave drift by itself should not have a dispersive effect on the surface floating *** were then conducted with small floating objects subjected to P-M spectral waves in a laboratory wave flume,and the experimental results reinforced the conclusion drawn.

关键词： dispersion surface contaminants random wave Stokes drift

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