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Floret-specific differences in gene expression and support for the hypothesis that tapetal degeneration of Zea mays L. occurs via programmed cell death

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Journal of Genetics and Genomics 2008年第10期35卷 603-616页

作者： David S. Skibbe Xiujuan Wang Lisa A. Borsuk daniel A. Ashlock Dan Nettleton patrick S. Schnable Department of Genetics Iowa State University Ames Iowa 50011 USA Department of Mathematics Iowa State University Ames Iowa 50011 USA Department of Statistics Iowa State University Ames Iowa 50011 USA Center for Plant Genomics Iowa State University Ames Iowa 50011 USA Department of Agronomy Iowa State University Ames Iowa 50011 USA

The maize （Zea mays） spikelet consists of two florets, each of which contains three developmentally synchronized anthers. Morphologically, the anthers in the upper and lower florets proceed through apparently similar developmental programs. To test for global differences in gene expression and to identify genes that are coordinately regulated during maize anther development, RNA samples isolated from upper and lower floret anthers at six developmental stages were hybridized to cDNA microarrays. Approximately 9% of the tested genes exhibited statistically significant differences in expression between anthers in the upper and lower florets. This finding indicates that several basic biological processes are differentially regulated between upper and lower floret anthers, including metabolism, protein synthesis and signal transduction. Genes that are coordinately regulated across anther development were identified via cluster analysis. Analysis of these results identified stage-specific, early in development, late in development and bi-phasic expression profiles. Quantitative RT-PCR analysis revealed that four genes whose homologs in other plant species are involved in programmed cell death are up-regulated just prior to the time the tapetum begins to visibly degenerate （i.e., the mid-microspore stage）. This finding supports the hypothesis that developmentally normal tapetal degeneration occurs via programmed cell death.

关键词： anther development programmed cell death microarray maize

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National assessment of Canadian pandemic preparedness: Employing InFluNet to identify high-risk areas for inter-wave vaccine distribution

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Infectious Disease Modelling 2017年第3期2卷 341-352页

作者： patrick Saunders-Hastings Bryson Quinn Hayes Robert Smith daniel Krewski University of Ottawa McLaughlin Centre for Population Health Risk Assessment850 Peter Morand CrescentOttawaOntarioK1G 5Z3Canada University of Ottawa School of EpidemiologyPublic Healthand Preventive MedicineFaculty of Medicine451 Smyth RoadOttawaONK1H 8M5Canada University of Ottawa Department of Mathematics585 King Edward AvenueOttawaONK1N 6N5Canada Risk Sciences International 55 Metcalfe StreetSuite 700OttawaONK1P 6L5Canada

Background:Influenza pandemics emerge at irregular and unpredictable intervals to cause substantial health,economic and social *** health-system response is vital to mitigating the consequences of future ***:We developed a mathematical model to assess the preparedness of Canadian health systems to accommodate pandemic-related increases in patient *** identify vulnerable areas,assess the potential of inter-wave vaccination to mitigate impacts and evaluate the association between demographic and health-system characteristics in order to identify predictors of pandemic ***:Modelled average attack rates were 23.7e37.2%with no intervention and 2.5 e6.4%with *** acute-care demand was 7.5e19.5%of capacity with no intervention and 0.6e2.6%with *** peak ICU demand was 39.3e101.8%with no intervention and 2.9e13.3%with *** mortality was 2258 e7944 with no intervention and 88e472 with *** of Southern Ontario were identified as most vulnerable to surges in patient *** strongest predictors of peak acute-care demand and ICU demand were acute-care bed capacity(R=0.8697;r^2=0.7564)and ICU bed capacity(R=0.8151;r^2=0.6644),*** characteristics had mild associations with predicted pandemic ***:Inter-wave vaccination provided adequate acute-care resource protection under all scenarios;ICU resource adequacy was protected under mild disease assumptions,but moderate and severe diseases caused demand to exceed expected availability in 21%and 49%of study areas,*** study informs priority vaccine distribution strategies for pandemic planning,emphasizing the need for targeted early vaccine distribution to high-risk individuals and areas.

关键词： consequences distribution Canadian

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推力和横向压力作用下加筋板破坏分析的理想化结构单元法(英文)

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船舶力学 2005年第3期9卷 60-76页

作者： patrick KAEDING daniel OLARU Masahiko FUJIKUBO 德国JAFO Technologie 罗马尼亚加拉茨“Dunarea de Joe”大学日本广岛大学

理想化结构单元法(ISU M )已经成为评估结构系统中承受载荷能力的一个有效工具。本文给出了最新的ISU M 板元公式,并考虑了双轴向推力和横向载荷对板元的加载。为了精确地模拟加筋板的性能,分别用梁—柱元和板元制作了肋材和板材的模型... 详细信息

理想化结构单元法(ISU M )已经成为评估结构系统中承受载荷能力的一个有效工具。本文给出了最新的ISU M 板元公式,并考虑了双轴向推力和横向载荷对板元的加载。为了精确地模拟加筋板的性能,分别用梁—柱元和板元制作了肋材和板材的模型。与有限元分析(FEA )的比较表明该方法对解决加筋板在横向压力和推力载荷下的问题是适用的。对箱形桁材的四点弯曲试验的分析表明与试验数据吻合良好。

关键词： ISUM 板元梁-柱元加筋板极限强度横向载荷箱形桁材

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Efficient Noninvasive FHB Estimation using RGB Images from a Novel Multiyear,Multirater Dataset

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Plant Phenomics 2023年第3期5卷 533-545页

作者： DominikRößle LukasPrey LudwigRamgraber AnjaHanemann danielCremers patrick OleNoack TorstenSchön AImotion Bavaria Technische Hochschule IngolstadtIngolstadtGermany Hochschule Weihenstephan-Triesdorf WeidenbachGermany Saatzucht Josef Breun GmbH and Co.KG HerzogenaurachGermany Technical University of Munich MunichGermany

Fusarium head blight(FHB)is one of the most prevalent wheat diseases,causing substantial yield losses and health *** phenotyping of FHB is crucial for accelerating resistance breeding,but currently used methods are time-consuming and *** present article suggests a noninvasive classification model for FHB severity estimation using red–green–blue(RGB)images,without requiring extensive *** model accepts images taken from consumer-grade,low-cost RGB cameras and classifies the FHB severity into 6 ordinal *** addition,we introduce a novel dataset consisting of around 3,000 images from 3 different years(2020,2021,and 2022)and 2 FHB severity assessments per image from independent *** used a pretrained EfficientNet(size b0),redesigned as a regression *** results demonstrate that the interrater reliability(Cohen’s kappa,κ)is substantially lower than the achieved individual network-to-rater results,e.g.,0.68 and 0.76 for the data captured in 2020,*** model shows a generalization effect when trained with data from multiple years and tested on data from an independent ***,using the images from 2020 and 2021 for training and 2022 for testing,we improved the F_(1)^(w) score by 0.14,the accuracy by 0.11,κ by 0.12,and reduced the root mean squared error by 0.5 compared to the best network trained only on a single year’s *** proposed lightweight model and methods could be deployed on mobile devices to automatically and objectively assess FHB severity with images from low-cost RGB *** source code and the dataset are available at https://***/cvims/FHB_classification.

关键词： network consuming breeding

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The Dark Side of Samsung’s Value Chain: The Human Costs of Cobalt Mining “BLOOD, SWEAT AND COBALT”

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Journal of Geoscience and Environment Protection 2021年第2期9卷 182-203页

作者： daniel Krummel patrick Siegfried International Business and Management Alliance Manchester Business School Manchester UK International Management Logistics & Supply Chain Management International School of Management Frankfurt Germany

Samsung has been implicitly linked to human rights abuses and wider social downgrading propagated within the Democratic Republic of Congo (DRC). Reports by different studies have shown artisanal cobalt mines (ASM) to exploit child labour and subject workers to perilous conditions. The IT multinational is dependent upon Congolese cobalt as a key element in lithiumion batteries used to produce their array of electronics. However, irresponsible cobalt sourcing practices undertaken by Tier 1 suppliers, Glencore and Huayou, have resulted in ASM operations being incorporated into Samsung’s global value chain, as Tier 2 suppliers. Analysis of the relationships underpinning Samsung’s cobalt value chain theoretical framework, highlights the presence of a relational governance structure, with captive elements among upstream Tier 1 and Tier 2 suppliers. Samsung is thereby reliant upon both Glencore and Huayou to transmit and enforce private codes of conduct down the value chain to expel human rights abuses. In conjunction, the DRC’s weak and unstable institutional environment has facilitated corruption and the improper enforcement of laws across the ASM industry. It is thereby imperative that Samsung takes ownership of the issues present within its value chain, as both Tier 1 suppliers and the Congolese government have failed to ensure responsible cobalt sourcing practices to date. This report recommends that Samsung adopt a holistic action plan, not only utilising their own resources and capabilities, but also those of critical stakeholders including Tier 1 suppliers, NGOs and the DRC and South Korean governments. Most prominently, this report suggests that supply chain transparency can be improved using certificates of origin and blockchain technology. Furthermore, it is recommended that poverty alleviation is targeted as a key measure through “Cobalt for Development”, an action plan designed to instigate both social and economic upgrading within ASM operations and the wider

关键词： Value Chain Ethics Child Labour

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Anti-N-methyl-D-aspartate receptor-associated encephalitis: A review of clinicopathologic hallmarks and multimodal imaging manifestations

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World Journal of Radiology 2024年第1期16卷 1-8页

作者： Bryce David Beutler Alastair E Moody Jerry Mathew Thomas Benjamin Phillip Sugar Mark B Ulanja daniel Antwi-Amoabeng Lucas Anthony Tsikitas Department of Radiology University of Southern CaliforniaKeck School of MedicineLos AngelesCA 90033United States Department of Anesthesiology University of UtahSalt Lake CityUT 84132United States Department of Internal Medicine Christus Ochsner St.Patrick HospitalLake CharlesLA 70601United States

Anti-N-methyl-D-aspartate receptor-associated encephalitis(NMDARE)is a rare immune-mediated neuroinflammatory condition characterized by the rapid onset of neuropsychiatric symptoms and autonomic *** mechanism of pathogenesis remains incompletely understood,but is thought to be related to antibodies targeting the GluN1 subunit of the NMDA receptor with resultant downstream dysregulation of dopaminergic *** adults are most frequently affected;the median age at diagnosis is 21 *** is a strong female predilection with a female sex predominance of 4:*** often develops as a paraneoplastic process and is most commonly associated with ovarian ***,NMDARE has also been described in patients with small cell lung cancer,clear cell renal carcinoma,and other benign and malignant *** is based on correlation of the clinical presentation,electro-encephalography,laboratory studies,and *** tomography,positron emission tomography,and magnetic resonance imaging are essential to identify an underlying tumor,exclude clinicopathologic mimics,and predict the likelihood of long-term functional *** imaging may be of value for prognostication and to assess the response to *** may involve high-dose corticosteroids,intravenous immunoglobulin,and plasma ***,we review the hallmark clinicopathologic features and imaging findings of this rare but potentially devastating condition and summarize diagnostic criteria,treatment regimens,and proposed pathogenetic mechanisms.

关键词： Anti-N-methyl-D-aspartate receptor-associated encephalitis Autoimmune encephalitis Encephalitis Ovarian teratoma Paraneoplastic syndrome Teratoma

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Environmental and energy requirements for different production biomass of Nile tilapia(Oreochromis niloticus)in recirculating aquaculture systems(RAS)in Kenya

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Aquaculture and Fisheries 2021年第6期6卷 593-600页

作者： daniel Mwendwa Wambua patrick G.Home James M.Raude Stephen Ondimu Department of Soil Water and Environmental EngineeringJomo Kenyatta University of Agriculture and TechnologyP.O.BOX 62000-00200NairobiKenya Department of Agricultural and Biosystems Engineering Jomo Kenyatta University of Agriculture and TechnologyP.O.BOX 62000-00200NairobiKenya

Recirculating Aquaculture Systems(RAS)offers a better option to increase aquaculture production with limited land and water resources while minimizing water *** biggest challenges in RAS is to maintain favorable water quality for the fish to *** practice of RAS in Kenya is minimal with the improper matching of RAS components and production densities for the existing few and in most cases,leading to a system *** study aimed at evaluating environmental and energy requirements for different production biomass of Nile tilapia in a RAS established in a controlled *** production densities and water flow rates were varied while at the same time,the water quality parameters(dissolved oxygen,ammonia,pH,electrical conductivity and temperature)were *** energy consumed for pumping and aeration was also *** stocking biomass varied from 2.3 kg/m^(3) to 10 kg/m^(3) while flow rate was varied from 2.0 L/min and increased at intervals of 1.0 L/min to the maximum attainable flow rate of 10.0 L/*** pumice rock packed in a 1000 L tank and equipped with a bell siphon was used as the *** removal reduced with increasing flow rate with removal rates of 75%at 2.0-3.0 L/min to 9%at 8.0-10.0 L/*** water pH increased with increasing flow rate with R^(2) ranging from 0.4 to *** conductivity increased with flow rate from 112 mg/L to as high as 209 mg/*** oxygen increased with flow rate and ranged from 1.0 mg/L to 7.0 mg/*** consumption increased with flow rate and raged from 0.4 kW h at 2.3 kg/m^(3) stocking biomass to 2.4 kW h at 10 kg/m^(3)stocking *** stocking densities and flow rates resulted to lower purification efficiencies and higher power consumptions than low stocking densities and flow *** order to maintain good RAS water quality,increased production and profits among farmers using RAS in Kenya,there is need to give proper advice on the right combination of st

关键词： Biofilter Flow rate Purification efficiency Stocking biomass Water quality

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Effects of Bradyrhizobium japonicumInoculation and Supplementation with Phosphorus on Macronutrients Uptake in Cowpea (Vigna unguiculata(L.) Walp)

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American Journal of Plant Sciences 2014年第4期5卷 442-451页

作者： daniel Nyoki patrick A. Ndakidemi School of Life Sciences and Bioengineering The Nelson Mandela African Institution of Science and Technology Arusha Tanzania

The current study was conducted to assess the effects of phosphorus supplementation and Bradyrhizobium japonicum inoculation on the availability and uptake of N, P, K, Mg, Ca and Na on cowpea. The experiment was laid out in a split plot design where the main plots comprised two inoculation levels (with and without inoculation of B. japonicum ) and sub plots contained four different levels of phosphorus (0, 20, 40, and 80 kg P/ha). The results indicated that B. japonicum inoculation and phosphorus supplementation significantly improved the uptake of N, P, K, Mg, Ca and Na in different cowpea tissues such as roots, pods, shoots, and whole plant relative to the control. The results also indicated that there was a significant interaction of B. japonicum and phosphorus on the uptake of sodium in the roots and whole cowpea plant in the screen house. Rhizobia inoculation and supplementation of phosphorus at 40 kg P/ha resulted in the improved uptake of the most elements over other treatments tested.

关键词： Mineral Elements Bioavailability Calcium Magnesium Sodium NPK Rhizosphere

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Influence of Bradyrhizobium japonicumand Phosphorus on Micronutrient Uptake in Cowpea. A Case Study of Zinc (Zn), Iron (Fe), Copper (Cu) and Manganese (Mn)

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American Journal of Plant Sciences 2014年第4期5卷 427-435页

作者： daniel Nyoki patrick A. Ndakidemi School of Life Sciences and Bioengineering The Nelson Mandela African Institution of Science and Technology Arusha Tanzania

The field and screen house experiments were carried out in the 2013 cropping season to assess the effects of B. japonicum inoculation and phosphorus supplementation on the uptake of micronutrients in the cowpea. The experiment was laid out in a split plot design where the main plots comprised two inoculation treatments (with and without B. japonicum inoculation) and sub plots included four different levels of phosphorus (0, 20, 40, and 80 kg P/ha). The results showed a significant improvement in the uptake of micronutrients in the B. japonicum inoculated treatments over the control. Phosphorus supplementation (40 kg P/ha) also showed a significant increase in the uptake of some micronutrients while decreasing the uptake of Zn in some plant organs. There was also a significant interaction between B. japonicum inoculation and phosphorus in the root uptake of Zn for the field experiment.

关键词： Bioavailability Legume P-Micronutrient Interactions Triple Super Phosphate

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Interactions of primary neuroepithelial progenitor and brain endothelial cells: distinct effect on neural progenitor maintenance and differentiation by soluble factors and direct contact

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Cell Research 2007年第7期17卷 619-626页

作者： Miguel A Gama Sosa Rita De Gasperi Anne B Rocher Gissel M Perez Keila Simons daniel E Cruz patrick R Hof Gregory A Elder Departments of Psychiatry Research and Development Service James J. Peters Department of Veterans Affairs Medical Center 130 West Kingsbridge Road Bronx New York 10468 USA Neuroscience Mount Sinai School of Medicine of New York University New York NY Department of Research and Development Service James J. Peters Department of Veterans Affairs Medical Center 130 West Kingsbridge Road Bronx New York 10468 USA

Neurovascular interactions are crucial for the normal development of the central nervous system. To study suchinteractions in primary cultures, we developed a procedure to simultaneously isolate neural progenitor and endothelialcell fractions from embryonic mouse brains. Depending on the culture conditions endothelial cells were found to favormaintenance of the neuroprogenitor phenotype through the production of soluble factors, or to promote neuronal differ-entiation of neural progenitors through direct contact. These apparently opposing effects could reflect differential cellularinteractions needed for the proper development of the brain.

关键词： differentiation culture endothelial cells neuroepithelial cells

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