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Black locust coppice stands homogenize soil diazotrophic communities by reducing soil net nitrogen mineralization

Forest Ecosystems 2022年第3期9卷 289-300页

作者： Kun Li Huimei Tian W.Keith Moser steven T.Overby L.Scott Baggett Ruiqiang Ni Chuanrong Li Weixing Shen Mountain Tai Forest Ecosystem Research Station of State Forestry Administration Key Laboratory of State Forestry Administration for Silviculture of the Lower Yellow RiverForestry College of Shandong Agricultural UniversityTai'an271018ShandongChina Rocky Mountain Research Station United States Forest Service2500 S.Pine Knoll Dr.FlagstaffAZ86001USA Rocky Mountain Research Station United States Forest Service240 West Prospect Fort CollinsCO80526USA Mount Tai Scenic Spot Management Committee Tai'an271000ShandongChina

Background:Black locust(BL,Robinia pseudoacacia)is considered a promising tree species for reforestation due to its great ability to fix ***,after two or three coppice-harvesting rotations,the productivity of BL *** soil microbial communities are affected and how these groups correlate with the nitrogen mineralization process across multi-generation stands remains ***:We investigated the composition and structure of free-living nitrogen-fixing microorganisms(diazotrophs)by sequencing the marker gene nifH and compared these results to levels of soil nitrogen mineralization in the bulk soil and rhizosphere in black locust plantations on Mount Tai,***:The results showed multi-generation BL coppice plantations decreased the total soil nitrogen(N),soil phosphorus(P),soil microbial biomass N(MBN),soil microbial biomass C(MBC),soil nitrification rate(Rn),soil ammonification rate(Ra),and net soil N mineralization rate(Rm),but significantly increased the concentration of soil NH_(4þ)-N to maintain sufficient NO_(3)^(-)*** dominant species in bulk soil and rhizosphere changed from Rhodopseudomonas(22.62%and 15.76%),unclassified_c_Alphaproteobacteria(22.37%and 29.28%),unclassified_o_Rhizobiales(15.40%and 13.31%),Bradyrhizobium(12.00%and 11.74%)in seedling plantations to Bradyrhizobium(45.95%and 47.86%)and Rhodopseudomonas(43.56%and 41.84%)in coppice plantations,*** test and Redundancy analysis(RDA)revealed that Rn,Ra,and Rm were the most important factors shaping the diazotrophic ***:Our results suggest that the multi-generation BL coppice plantation can homogenize soil diazotrophic communities,which is mainly regulated by the available N loss caused by nitrogen *** the management technology of coppice plantations will provide more beneficial external consumption.

关键词： Black locust plantation nifH gene Nitrogen mineralization Coppice Soil nutrient

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Ground-based hyperspectral remote sensing for weed management in crop production

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International j.urnal of Agricultural and Biological Engineering 2016年第2期9卷 98-109页

作者： Yanbo Huang Matthew A.Lee steven j.Thomson Krishna N.Reddy United States Department of Agriculture Agricultural Research ServiceCrop Production Systems Research UnitPO Box 350Stoneville MS 38776USA Department of Electrical and Computer Engineering Mississippi State UniversityMississippi State MS 39762USA United States Department of Agriculture National Institute of Food and AgricultureWashington DC 20024USA

Agricultural remote sensing has been developed and applied in monitoring soil,crop growth,weed infestation,insects,diseases and water status in farm fields to provide data and information to guide agricultural management *** agriculture has been implemented through prescription mapping of crop fields at different scales with the data remotely sensed from space-borne,airborne and ground-based ***-based remote sensing techniques offer portability,flexibility and controllability in applications for precision *** weed management,crop inj.ry from off-target herbicide spray drift and herbicide resistance in weeds are two important *** precision weed management,ground-based hyperspectral remote sensing techniques were developed for detection of crop inj.ry from dicamba and differentiation between glyphosate resistant and sensitive *** research presents the techniques for ground-based hyperspectral remote sensing for these two *** illustrate the advantages of ground-based hyperspectral remote sensing for precision weed management.

关键词： ground-based remote sensing hyperspectral crop inj.ry herbicide resistance precision agriculture

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A Pressure-Correction Scheme for Rotational Navier-Stokes Equations and Its Application to Rotating Turbulent Flows

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Communications in Computational Physics 2011年第3期9卷 740-755页

作者： Dinesh A.Shetty j.e Shen Abhilash j.Chandy steven H.Frankel School of Mechanical Engineering Purdue UniversityWest LafayetteIN 47907USA School of Mathematical Sciences Xiamen UniversityXiamenChina Department of Mathematics Purdue UniversityWest LafayetteIN 47907USA Department of Mechanical Engineering University of AkronAkronOH 44325USA

The rotational incremental pressure-correction(RIPC)scheme,described in Timmermans et al.[***.,22(1996)]and Shen et al.[***.,73(2003)]for non-rotational Navier-Stokes equations,is extended to rotating incompressible *** method is implemented in the context of a pseudo Fourier-spectral code and applied to several rotating laminar and turbulent *** performance of the scheme and the computational results are compared to the socalled diagonalization method(DM)developed by Morinishi et al.[***.,22(2001)].The RIPC predictions are in excellent agreement with the DM predictions,while being simpler to implement and computationally more *** RIPC scheme is not in anyway limited to implementation in a pseudo-spectral code or periodic boundary conditions,and can be used in complex geometries and with other suitable boundary conditions.

关键词： Rotating turbulent flow pressure-correction Navier-Stokes equations Fourier-spectral method

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Hepatitis C risk assessment,testing and referral for treatment in urban primary care:Role of race and ethnicity

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World j.urnal of Gastroenterology 2007年第7期13卷 1074-1078页

作者： Stacey B Trooskin Victor j.Navarro Robert j.Winn David j.Axelrod A Scott McNeal Maricruz Velez steven K Herrine Simona Rossi Division of Gastroenterology and Hepatology Thomas Jefferson University Philadelphia PA 19107 United States Department of Family Medicine Thomas Jefferson University Philadelphia PA 19107 United States Division of Internal Medicine Thomas Jefferson University Philadelphia PA 19107 United States Delaware Valley Community Health Inc. Philadelphia PA 19107 United States

AIM: To determine rates of hepatitis C (HCV) risk factor ascertainment, testing, and referral in urban primary care practices, with particular attention to the effect of race and ethnicity. METHODS: Retrospective chart review from four primary care sites in Philadelphia; two academic primary care practices and two community clinics was performed. Demographics, HCV risk factors, and other risk exposure information were collected. RESULTS: Four thousand four hundred and seven charts were reviewed. Providers documented histories of inj.ction drug use (IDU) and transfusion for less than 20% and 5% of patients, respectively. Only 55% of patients who admitted IDU were tested for HCV. Overall, minorities were more likely to have information regarding a risk factor documented than their white counterparts (79% vs 68%, P < 0.0001). Hispanics were less likely to have a risk factor history documented, compared to blacks and whites (P < 0.0001). Overall, minorities were less likely to be tested for HCV than whites in the presence of a known risk factor (23% vs 35%, P = 0.004). Among patients without documentation of risk factors, blacks and Hispanics were more likely to be tested than whites (20% and 24%, vs 13%, P < 0.005, respectively). CONCLUSION: (1) Documentation of an HCV risk factor history in urban primary care is uncommon, (2)Racial differences exist with respect to HCV risk factor ascertainment and testing, (3) Minority patients, positive for HCV, are less likely to be referred for subspecialty care and treatment. Overall, minorities are less likely to be tested for HCV than whites in the presence of a known risk factor.

关键词：丙型病毒肝炎测试治疗种族

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Induction of defence gene expression by oligogalacturonic acid requires in- creases in both cytosolic calcium and hydrogen peroxide in Arabidopsis thaliana

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Cell Research 2004年第3期14卷 234-240页

作者： steven j.NEILL Centre for Research in Plant Science University of the West of England Bristol Coldharbour Lane Bristol BS16 1QY UK

Responses to oligogalacturonic acid （OGA） were determined in transgenic Arabidopsis thaliana seedlings expressing the calcium reporter protein aequorin. OGA stimulated a rapid, substantial and transient increase in the concentration of cytosolic calcium （[Ca2+]cyt） that peaked after ca. 15 s. This increase was dose-dependent, saturating at ca. 50 μg Gal equiv/ml of OGA. OGA also stimulated a rapid generation of H2O2. A small, rapid increase in H2O2 content was followed by a much larger oxidative burst, with H2O2 content peaking after ca. 60 min and declining thereafter. Induction of the oxidative burst by OGA was also dose-dependent, with a maximum response again being achieved at ca. 50 μg Gal equiv/mL. Inhibitors of calcium fluxes inhibited both increases in [Ca2+]cyt and [H2O2], whereas inhibitors of NADPH oxidase blocked only the oxidative burst. OGA increased strongly the expression of the defence-related genes CHS, GST, PAL and PR-1. This induction was suppressed by inhibitors of calcium flux or

关键词： Arabidopsis thaliana cytosolic calcium defence gene expression hydrogen peroxide OGA.

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Development and prospect of unmanned aerial vehicle technologies for agricultural production management

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International j.urnal of Agricultural and Biological Engineering 2013年第3期6卷 1-10页

作者： Yanbo Huang steven j.Thomson W.Clint Hoffmann Yubin Lan Bradley K.Fritz United States Department of Agriculture Agricultural Research ServiceCrop Production Systems Research UnitStonevilleMS 38776USA United States Department of Agriculture Agricultural Research ServiceAreawide Pest Management Research UnitCollege StationTX 77845USA

Unmanned aerial vehicles have been developed and applied to support agricultural production *** with piloted aircraft,an Unmanned Aerial Vehicle(UAV)can focus on small crop fields at lower flight altitudes than regular aircraft to perform site-specific farm management with higher *** can also“fill in the gap”in locations where fixed winged or rotary winged aircraft are not readily *** agriculture,UAVs have primarily been developed and used for remote sensing and application of crop production and protection *** of fertilizers and chemicals is frequently needed at specific times and locations for site-specific *** monitoring of crop plant health is often required at very high resolution for accurate site-specific management as *** paper presents an overview of research involving the development of UAV technology for agricultural production ***,systems and methods are examined and *** limitations of current UAVs for agricultural production management are discussed,as well as future needs and suggestions for development and application of the UAV technologies in agricultural production management.

关键词： unmanned aerial vehicle aircraft aerial application technology sensor remote sensing precision agriculture agricultural aviation

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Multispectral imaging systems for airborne remote sensing to support agricultural production management

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International j.urnal of Agricultural and Biological Engineering 2010年第1期3卷 50-62页

作者： Yanbo Huang steven j.Thomson Yubin Lan Stephan j.Maas USDA-ARS Crop Production Systems Research Unit StonevilleMS 38776USA USDA ARS Areawide Pest Management Research Unit College StationTX 77845USA Texas Tech University LubbockTX 79409USA

This study investigated three different types of multispectral imaging systems for airborne remote sensing to support management in agricultural application and *** three systems have been used in agricultural *** range from low-cost to relatively high-cost,manually operated to automated,multispectral composite imaging with a single camera and integrated imaging with custom-mounting of separate *** issues regarding use of the imaging systems were described and *** low-cost system,due to band saturation,slow imaging speed and poor image quality,is more preferable to slower moving platforms that can fly close to the ground,such as unmanned autonomous helicopters,but not recommended for low or high altitude aerial remote sensing on fixed-wing *** the restriction on payload unmanned autonomous helicopters are not recommended for high-cost systems because they are typically heavy and difficult to *** system with intermediate cost works well for low altitude aerial remote sensing on fixed-wing aircraft with field shapefile-based global positioning *** system also works well for high altitude aerial remote sensing on fixed-wing aircraft with global positioning triggering or manually *** custom-built system is recommended for high altitude aerial remote sensing on fixed-wing aircraft with waypoint global positioning triggering or manually operated.

关键词： airborne remote sensing multispectral imaging agricultural production management

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MULTISPECTRAL IMAGING SYSTEMS FOR AIRBORNE REMOTE SENSING TO SUPPORT SITE-SPECIFIC AGRICULTURAL MANAGEMENT

MULTISPECTRAL IMAGING SYSTEMS FOR AIRBORNE REMOTE SENSING TO...

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亚洲精细农业与计算机农业应用联合大会

作者： steven. j. Thomson Stephan j. Maas USDA ARS Application and Production Technology Research Unit Stoneville MS 38776 USA Texas Tech University Lubbock TX 79409 USA

Remote sensing has shown promise as a tool for site-specific management in agricultural application and production. Earth-observing satellite systems have an advantage for large-scale analysis at regional levels but are limited in spatial resolution. High-resolution satellite systems have been available in recent years, but scheduling these systems for appropriate bands, location of flight, proper altitude, and time of acquisition is difficult. Airborne remote sensing systems offer a flexible, do-it-yourself platform to configure for high quality, high spatial resolution imagery at any desired spectral combination, location, altitude, and time. Use of airborne hyperspectral remote sensing in agriculture has been steadily increasing during the past decade. Compared with hyperspectral systems, multispectral systems are much lower in cost and are less data-intensive. Airborne multispectral techniques are cost-effective and still a good source of crop, soil, or ground cover information for agricultural application and production. This paper investigates three different types of multispectral imaging systems for airborne remote sensing to support site-specific management in agricultural application and production. The three systems have been used in agricultural studies. They range from low-cost to relatively high-cost, manually operated to automated, multispectral composite imaging with a single camera and individual imaging with assembly of separate cameras. Practical issues regarding use of the imaging systems are described and discussed. The advantages and disadvantages of each system are summarized and compared in different configurations. The information is provided for developing practical aerial remote sensing systems. System applications are suitable for fixed-wing aircraft and unmanned autonomous helicopter or fixed-wing platforms.

关键词： Airborne Remote Sensing Multispectral Imaging Site-Specific Management

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Understanding and managing sanitary risks due to rodent zoonoses in an African city: beyond the Boston Model

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Integrative Zoology 2008年第1期3卷 38-50页

作者： Peter j.TAYLOR Lorraine ARNTZEN Mel HAYTER Malcolm ILES j.hn FREAN steven BELMAIN Durban Natural Science Museum eThekwini Libraries and Heritage DepartmentDurbanSouth Africa National Institute for Communicable Diseases National Health Laboratory ServiceSandringhamSouth Africa City Health:Communicable Diseases eThekwini MunicipalityDurbanSouth Africa Natural Resources Institute Chatham MaritimeKentUK

The Boston Model describes a successful rodent management plan that succeeded in a first-world city in the *** third-world cities, which often contain informal shack settlements, it is debatable whether the Boston Modelwould apply. In Durban, a maj.r harbor city of three million people on the east coast of South Africa, we investigatedthe sanitary risks due to rodents in both formal (residential and commercial) and informal (shacks) sectors,and we evaluated the relative merits of different management interventions suggested by the Boston Model. Bloodand tissue samples of six species (Rattus norvegicus, R. tanezumi, R. rattus, Mus musculus, Mastomys natalensis,Tatera brantsi) from 262 live-trapped rodents from 54 localities were tested for antibodies or DNA for plague (n =193: antibody test), leptospirosis (n = 221 for antibody test;n = 69 for polymerase chain reaction test for DNA) andtoxoplasmosis (n = 217: antibody test). We conducted a socioeconomic survey of 90 household to determine environmentaland socioeconomic disease risk factors in the shack settlement of Cato Crest . No rodents wereseropositive for plague, but nine Norway rats, R. norvegicus (4.1% of the sample tested) were seropositive fortoxoplasmosis, and 22 R. norvegicus (10.0% of sample tested) were seropositive for leptospirosis. Disease endemicareas were concentrated in Cato Crest and the commercial district of Durban. Serology tests of humans living inCato Crest (n = 219) showed 0% exposure to plague, 23% to leptospirosis and 35% to toxoplasmosis. Comparedwith shack-dwellers, the residents of brick houses had slightly lower levels of exposure to leptospirosis andtoxoplasmosis. Based on our results, environmental hygiene and rodent-trapping campaigns were launched in CatoCrest. The initiative owes much of its current success to implementation of the principles inherent in the BostonModel, even though certain elements were lacking.

关键词： Durban leptospirosis plague rodent zoonoses toxoplasmosis.

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Colonic ulcerations may predict steroid-refractory course in patients with ipilimumab-mediated enterocolitis

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World j.urnal of Gastroenterology 2017年第11期23卷 2023-2028页

作者： Animesh j.in Evan j.Lipson William H Sharfman steven R Brant Mark G Lazarev Division of Gastroenterology and Hepatology Department of Internal MedicineUniversity of North Carolina Chapel Hill Department of Oncology Johns Hopkins University School of Medicine and Sidney Kimmel Comprehensive Cancer Center Division of Gastroenterology and Hepatology Department of Internal MedicineJohns Hopkins University School of Medicine

AIM To investigate management of patients who develop ipilimumab-mediated enterocolitis, including association of endoscopic findings with steroid-refractory symptoms and utility of infliximab as second-line *** We retrospectively reviewed all patients at our centerwith metastatic melanoma who were treated with ipilimumab between March 2011 and May 2014. All patients received a standard regimen of intravenous ipilimumab 3 mg/kg every 3 wk for four doses or until therapy was stopped due to toxicity or disease progression. Basic demographic and clinical data were collected on all patients. For patients who developed grade 2 or worse diarrhea(increase of 4 bowel movements per day), additional data were collected regarding details of gastrointestinal symptoms, endoscopic findings and treatment course. Descriptive statistics were *** A total of 114 patients were treated with ipilimumab during the study period and all were included. Sixteen patients(14%) developed ≥ grade 2 diarrhea. All patients were treated with high-dose corticosteroids(1-2 mg/kg prednisone daily or equivalent). Nine of 16 patients(56%) had ongoing diarrhea despite highdose steroids. Steroid-refractory patients received one dose of intravenous infliximab at 5 mg/kg, and all but one had brisk resolution of diarrhea. Fourteen of the patients underwent either colonoscopy or sigmoidoscopy with variable endoscopic findings, ranging from mild erythema to colonic ulcers. Among 8 patients with ulcers demonstrated by sigmoidoscopy or colonoscopy, 7 patients(88%) developed steroidrefractory symptoms requiring infliximab. With a median follow-up of 264 d, no maj.r adverse events associated with prednisone or infliximab were *** In patients with ipilimumab-mediated enterocolitis, the presence of colonic ulcers on endoscopy was associated with a steroid-refractory course.

关键词： Ipilimumab Melanoma Enterocolitis Colitis Infliximab Corticosteroid Colonic ulcer

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