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The main physical properties of planosol in maize(Zea mays L.) cultivation under different long-term reduced tillage practices in the Baltic region

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Journal of Integrative Agriculture 2015年第7期14卷 1309-1320页

作者： k?stutis Romaneckas Egidijus ?arauskis Dovil? Avi?ienyt? Sidona Buragien? david Arney Institute of Agrosystems and Soil Sciences Aleksandras Stulginskis University Institute of Agricultural Engineering and Safety Aleksandras Stulginskis University Department of Nutrition and Animal Products Quality Institute of Veterinary Medicine and Animal Sciences Estonian University of Life Sciences

The impact of sustainable reduced tillage （RT） on the physical properties of soil is well documented worldwide; however, there is no precise information about the influence of long-term RT or no-till （NT） on the soils at the boundary for grain maize-growing in the semi-humid subarctic climate conditions of the Baltic states, especially on the formation of a hard- ened upper soil layer （10-15 cm in depth） --＂loosening hardpan＂. This study was carried out at the Research Station of Aleksandras Stulginskis University, Lithuania from 2009-2012. The investigations were based on a long-term （since 1988） field experiment. The aim of the investigation was to ascertain the influence of reduced primary tillage on the main soil＇s physical properties. This study examined soils that were deep ploughing （DP）, shallow ploughing （SP）, deep cultivation （DC）, shallow cultivation （SC）, and no-till （NT）. Reducing the tillage intensity to NT had no significant effect on the structural soil＇s composition; however, the stability of the structure of the 〉1 and 〉0.25 mm-size fractions was significantly higher in the non-reversibly tilled （DC, SC） and NT plots. The penetration resistance of the DP soils was less after primary tillage and wintering, and became similar to the NT plots at the end of the maize growth season. After primary tillage and wintering, the soil moisture content in the upper soil layer （0-5 cm depth） of the NT plots was 17-49 and 16-18% higher than that in the DP. Long-term reduction of primary tillage up to NT generally had no significant effect on the moisture content and soil bulk density of the 0-10 and 10-20 cm layers. The results showed that long-term RT stabilized the physical quality of soil. Less soil penetration resistance was established in the DP plots compared to both RT and NT, however, indicators of the formation of a uniform ＂loosening hardpan＂ layer were not found. It is summarized that long-term RT or NT systems stabilize, or may increase, the physical

关键词： bulk density maize moisture content penetration resistance reduced tillage soil aggregation

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Integrating flood depth and plant resistance with chlorantraniliprole seed treatments for management of rice water weevil, Lissorhoptrus oryzophilus （Coleoptera： Curculionidae）

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Insect Science 2015年第5期22卷 679-687页

作者： Srinivas k. Lanka david C. Blouin Michael J. Stout Department of Entomology Louisiana State University Agricultural Center Baton Rouge LA 70803 USA

Chlorantraniliprole seed treatments in rice provide effective suppression of rice water weevil populations in the United States; however, heavy reliance on prophylac- tic insecticide treatments as a sole strategy could destabilize management programs for this insect. The present research evaluated the compatibility of seed treatments with two other potential management tactics--plant resistance and shallow flooding-by conducting two split-plot experiments in 2009 and 2011. In both experiments, no substantial antago- nism was found among the 3 different tactics. Statistical interactions in these experiments arose from the strong and persistent effects of chlorantraniliprole on larval densities rather than incompatibility of tactics. In 2009, weevil densities differed among varieties and were significantly lower on the cultivar ＂Jefferson.＂ In 2011, weevil densities were reduced sig- nificantly in shallow-flooded plots compared to deep-flooded plots. Significant reductions in weevil numbers by chlorantraniliprole seed treatments, even at application rates 5 fold lower than commercially recommended rates, demonstrated the potential to reduce appli- cation rates of this highly potent larvicide. These latter results suggest that future studies on the relationship between chlorantraniliprole seed treatment rate and weevil fitness are warranted.

关键词： chlorantraniliprole compatibility integrated management plant resistance rice water weevil seed treatments

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Topography and human disturbances are major controlling factors in treeline pattern at Barun and Manang area in the Nepal Himalaya

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Journal of Mountain Science 2017年第1期14卷 119-127页

作者： Parveen k.CHHETRI krishna B.SHRESTHA david M.CAIRNS Department of Geography Texas A&M University College Station TX 77840 USA UiB Global Jekteviksbakken 31 PO Box 7800 5020 Bergen Norway

The alpine treeline ecotone is an important component of mountain ecosystems of the Nepal Himalaya; it plays a vital role in the livelihood of indigenous people,and provides ecosystem services. However,the region faces a problem of paucity of data on treeline characteristics at the regional and landscape scales. Therefore,we used Remote Sensing(RS),and Geographic Information Science(GIS) approaches to investigate cross-scale interactions in the treeline ecotone. Additionally,European Space Agency land cover map,International Center for Integrated Mountain Development(ICIMOD) land cover map,ecological map of Nepal,and United States Geological Survey Shuttle Radar Topography Mission-Digital Elevation Model were used to analyze treeline pattern at the regional scale. Digital Globe high-resolution satellite imagery of Barun(eastern Nepal) and Manang(central Nepal) were used to study treeline patterns at the landscape scale. Treeline elevation ranges from 3300-4300 m above sea level. Abies spectabilis,Betula utilis,and Pinus wallichiana are the main treeline-forming species in the Nepal Himalaya. There is an east to west treeline elevationgradient at the regional scale. No slope exposure is observed at the regional scale; however,at the landscape scale,slope exposure is present only in a disturbed area(Manang). Topography and human disturbance are the main treeline controlling factor in Barun and Manang respectively.

关键词： Alpine Treeline Mountain ecosystem Himalaya Remote Sensing(RS) Geographic Information Science(GIS)

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Studies on the cytocompatibility,mechanical and antimicrobial properties of 3D printed poly(methyl methacrylate)beads

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Bioactive Materials 2018年第2期3卷 157-166页

作者： david k.Mills Uday Jammalamadaka karthik Tappa Jeffery Weisman Center for Biomedical Engineering and Rehabilitation Science USA The School of Biological Sciences Louisiana Tech UniversityRustonLA 71272USA

Osteomyelitis is typically a bacterial infection(usually from Staphylococcus)or,more rarely,a fungal infection of the *** can occur in any bone in the body,but it most often affects the long bones(leg and arm),vertebral(spine),and bones of the *** success in osteomyelitis is due to their ability to form biofilms which inhibit the wound healing process and increases resistance to anti-infective ***,biofilms do not allow easy penetration of antibiotics into their matrix making clinical treatment a *** development of local antibiotic delivery systems that deliver high concentrations of antibiotics to the affected site is an emerging area of research with great *** treatment includes antibiotic therapy,either locally or systemically and refractory cases of osteomyelitis may lead to surgical intervention and a prolonged course of antibiotic treatment involving placement of antibiotic-doped beads or spacers within the wound *** are disadvantages with this treatment modality including insufficient mixing of the antibiotic,lack of uniform bead size,resulting in lower antibiotic availability,and limitations on the antibiotics ***,a method is needed to address biofilm formations in the wound and on the surface of the surgical implants to prevent *** this study,we show that all antibiotics studied were successfully doped into PMMA and antibiotic-doped 3D printed beads,disks,and filaments were easily *** growth inhibition capacity of the antibiotic-loaded PMMA 3D printed constructs was also demonstrated.

关键词： 3D printing Antibacterials Drug delivery Halloysite nanotubes Medical devices Nanotechnology

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An evaluation of the role played by remote sensing technology following the World Trade Center attack

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Earthquake Engineering and Engineering Vibration 2003年第1期2卷 159-168页

作者： Charles k.Huyck Beverley J.Adams david I.kehrlein ImageCat Inc.400 OceangateSuite 1050Long BeachCA90802USA Senior Vice President ImageCat Inc.400 OceangateSuite 1050Long BeachCA90802USA Project Scientist ImageCat Inc.6047 Woodhaven AvenueCarmichaelCA95608USA Vice PresidentGIS Operations

Remote sensing technology has been widely recognized for contributing to emergency response efforts after the World Trade Center attack on September 11th, 2001. The need to coordinate activities in the midst of a dense, yet relatively small area, made the combination of imagery and mapped data strategically useful. This paper reviews the role played by aerial photography, satellite imagery, and LIDAR data at Ground Zero. It examines how emergency managers utilized these datasets, and identifies significant problems that were encountered. It goes on to explore additional ways in which imagery could have been used, while presenting recommendations for more effective use in future disasters and Homeland Security applications. To plan adequately for future events, it was important to capture knowledge from individuals who responded to the World Trade Center attack. In recognition, interviews with key emergency management and geographic information system (GIS) personnel provide the basis of this paper. Successful techniques should not be forgotten, or serious problems dismissed. Although widely used after September 11th, it is important to recognize that with better planning, remote sensing and GIS could have played an even greater role. Together with a data acquisition timeline, an expanded discussion of these issues is available in the MCEER/NSF report “Emergency Response in the Wake of the World Trade Center Attack; The Remote Sensing Perspective” (Huyck and Adams, 2002) keywords World Trade Center (WTC) - terrorism - emergency response - emergency management - ground zero - remote sensing - emergency operations - disasters - geographic information systems (GIS) - satellite imagery - synthetic aperture radar (SAR) - light detection and ranging imagery (LIDAR)

关键词： World Trade Center (WTC) terrorism emergency response emergency management ground zero remote sensing emergency operations disasters geographic information systems (GIS) satellite imagery synthetic aperture radar (SAR) light detection and ranging imagery (LIDAR)

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Quantitative analysis of ruminal methanogenic microbial populations in beef cattle divergent in phenotypic residual feed intake(RFI)offered contrasting diets

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Journal of Animal Science and Biotechnology 2014年第4期5卷 439-447页

作者： Ciara A Carberry david A kenny Alan k kelly Sinead M Waters Animal and Bioscience Research Department Animal and Grassland Research and Innovation CentreTeagascGrangeDunsanyCo.MeathIreland UCD School of Agriculture Food Science and Veterinary MedicineCollege of Life SciencesUniversity College DublinBelfieldDublin 4Ireland

Background：Methane（CH_4） emissions in cattle are an undesirable end product of rumen methanogenic fermentative activity as they are associated not only with negative environmental impacts but also with reduced host feed *** aim of this study was to quantify total and specific rumen microbial methanogenic populations in beef cattle divergently selected for residual feed intake（RFI） while offered（i） a low energy high forage（HF） diet followed by（ii） a high energy low forage（LF） *** fluid was collected from 14 high（H）and 14 low（L） RFI animals across both dietary *** real time PCR（qRT-PCR） analysis was conducted to quantify the abundance of total and specific rumen methanogenic *** correlation analysis was used to investigate the association between the relative abundance of methanogens and animal performance,rumen fermentation variables and diet ***：Abundance of methanogens,did not differ between RFI ***,relative abundance of total and specific methanogen species was affected（P〈 0.05） by diet type,with greater abundance observed while animals were offered the LF compared to the HF ***：These findings suggest that differences in abundance of specific rumen methanogen species may not contribute to variation in CH_4 emissions between efficient and inefficient animals,however dietary manipulation can influence the abundance of total and specific methanogen species.

关键词： Bovine qRT-PCR Residual feed intake Rumen methaongens

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Presentation, patterns and predictive value of baseline liver tests on outcomes in COVID-19 patients without chronic liver disease

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World Journal of Gastroenterology 2021年第42期27卷 7350-7361页

作者： david Bernstein Nitzan Roth Angela kim Marica Epstein david Hirschwerk Charlotte L kvasnovsky Sanjaya k Satapathy Department of Medicine/Hepatology Northwell HealthZucker School of Medicine at Hofstra/NorthwellManhassetNY 11030United States Division of Infectious Diseases Department of Medicine Northwell HealthZucker School of Medicine at Hofstra/NorthwellManhassetNY 11030United States Cohen Children's Medical Center Zucker School of Medicine at Hofstra/NorthwellNew Hyde ParkNY 11042United States

BACkGROUND Coronavirus disease 2019(COVID-19)infection is known to cause abnormal hepatic *** long term consequences of such elevations are *** To assessed the prevalence and prognostic value of initial liver enzymes in a large cohort of COVID-19 *** We reviewed electronic medical records of 10614 COVID-19 patients without known chronic liver disease who were admitted to our health system from March 1,2020,to April 30,*** analyzed baseline demographics and liver *** primary outcome was in-hospital mortality,and the secondary outcome was a composite of in-hospital mortality or need for mechanical *** Subjects with abnormal liver tests had increased risks of mortality and composite outcome when compared to patients with normal measurements on unadjusted analysis and after adjustment for demographic *** In our diverse patient population,liver enzyme abnormalities are associated with increased mortality and the need for mechanical ventilation in subjects without chronic liver *** patients are at the greatest risk for poor outcomes.

关键词： COVID-19 Liver enzymes Outcomes Predictors

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Development of the sexually dimorphic nucleus of the preoptic area and the influence of estrogen-like compounds

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Neural Regeneration Research 2013年第29期8卷 2763-2774页

作者： Zhen He Sherry Ann ferguson Li Cui Lazar John Greenfield Merle Gale Paule Division of Neurotoxicology National Center for Toxicological ResearchFood and Drug Administration Department of Neurology University of Arkansas for Medical Sciences

One of the well-defined sexually dimorphic structures in the brain is the sexually dimorphic nucleus, a cluster of cells located in the preoptic area of the hypothalamus. The rodent sexually dimorphic nucleus of the preoptic area can be delineated histologically using conventional Nissl staining or immunohistochemically using calbindin D28k immunoreactivity. There is increasing use of the cal- bindin D28k-delineated neural cluster to define the sexually dimorphic nucleus of the preoptic area in rodents. Several mechanisms are proposed to underlie the processes that contribute to the sexual dimorphism （size difference） of the sexually dimorphic nucleus of the preoptic area. Recent evidence indicates that stem cell activity, including proliferation and migration presumably from the 3^rd ventricle stem cell niche, may play a critical role in the postnatal development of the sexually dimorphic nucleus of the preoptic area and its distinguishing sexually dimorphic feature： a signifi-cantly larger volume in males. Sex hormones and estrogen-like compounds can affect the size of the sexually dimorphic nucleus of the preoptic area. Despite considerable research, it remains un-clear whether estrogen-like compounds and/or sex hormones increase size of the sexually dimor-phic nucleus of the preoptic area via an increase in stem cell activity originating from the 3^rd ventricle stern cell niche.

关键词： neural regeneration review sexual orientation sexual behavior calbindin D28k estrogen-likecompound bisphenol A neural stem cells grants-supported paper neuroregeneration

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Near-Wall Flow in the Blade Cascades Representing Last Rotor Root Sections of Large Output Steam Turbines

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Journal of Thermal Science 2021年第1期30卷 220-230页

作者： ŠIMURDA david FÜRST Jiří HÁLA Jindřich LUXA Martin BOBČÍk Marek NOVÁk Ondřej SYNÁČJaroslav Institute of Thermomechanics of the Czech Academy of Sciences Prague 18200Czech Republic Dpt.of Technical Mathematics Faculty of Mechanical EngineeringCTU in PraguePrague 12000Czech Republic Doosan Skoda Power Pilsen 30100Czech Republic

This paper investigates the flow past two variants of root section profile cascades for a last stage rotor considering three-dimensional flow structures in the near-wall *** were drawn based on RANS numerical simulations of both variants and on the experimental data obtained by the 3 D traversing in the exit flow field of one of the *** of 3 D structures at two different regimes and its influence on aerodynamic characteristics of the blade cascades was *** distributions of Mach number along the profiles were compared with 2 D optical measurements and its distortion due to the presence of the sidewall was *** interaction between main vortical structures was described and its influence on the loading of the blades,mechanical energy losses and exit flow angle was *** results showed that for a front loaded blade the vortical structures appeared earlier and at a larger extent than for an aft loaded ***,due to different Mach number distribution,contribution of end wall flow to the energy losses was lower in the case of the aft loaded *** influence of the near wall flow on the loading was found to be rather weak while the deviation of the exit flow angle appeared to be comparable for both of the variants.

关键词： turbine blade cascade secondary flow near wall flow supersonic flow CFD experiment

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电力市场中的投标策略

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电力系统自动化 2000年第14期24卷 1-6页

作者：文福拴 A.k.david 浙江大学电力经济与信息化研究所杭州310027 香港理工大学电机系

在电力市场环境下 ,发电公司可通过采用策略性的投标来取得最大利润。另一方面 ,市场调节或监管机构 (regulator)需要评估发电公司的策略性投标行为 ,考察滥用市场力 (market power)的可能性 ,以确定适当的市场结构和管理规则 ,确保市... 详细信息

在电力市场环境下 ,发电公司可通过采用策略性的投标来取得最大利润。另一方面 ,市场调节或监管机构 (regulator)需要评估发电公司的策略性投标行为 ,考察滥用市场力 (market power)的可能性 ,以确定适当的市场结构和管理规则 ,确保市场竞争。这样 ,研究最优的投标策略是发电公司和市场调节机构都感兴趣的课题。近几年中 ,这方面的研究工作相当活跃 ,发表了数十篇论文。文中对这一领域的研究工作进行简要的综述。

关键词：电力市场投标策略市场力寡头垄断电力工业

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