976 resultados para Oklahoma State University
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We describe the climatology of the western United States as seen from two 1-month perspectives, January and July 1988, of the National Meteorological Center large-scale global analysis, the Colorado State University Regional Atmospheric Modeling System (RAMS), and various station observation sets. An advantage of the NMC analysis and the RAMS is that they provide a continuous field interpolation of the meteorological variables. It is more difficult to describe spatial meteorological fields from the available sparse station networks. We assess accuracy of the NMC analysis and RAMS by finding differences between the analysis, the model, and station values at the stations. From these comparisons, we find that RAMS has much more well-developed mesoscale circulation, especially in the surface wind field. However, RAMS climatological and transient fields do not appear to be substantially closer than the larger-scale analysis to the station observations. The RAMS model does provide other meteorological variables, such as precipitation, which are not readily available from the archives of the global analysis. Thus, RAMS could, at the least, be a tool to augment the NMC large-scale analyses.
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The Indo-Pacific lionfishes, Pterois miles and P. volitans, are now established along the Southeast U.S. and Caribbean and are expected to expand into the Gulf of Mexico and Central and South America. Prior to this invasion little was known regarding the biology and ecology of these lionfishes. I provide a synopsis of chronology, taxonomy, local abundance, reproduction, early life history and dispersal, venomology, feeding ecology, parasitology, potential impacts, and possible control and management strategies for the lionfish invasion. This information was collected by review of the literature and by direct field and experimental study. I confirm the existence of an unusual supraocular tentacle phenotype and suggest that the high prevalence of this phenotype in the Atlantic is not the result of selection, but likely ontogenetic change. To describe the trophic impacts of lionfish, I report a comprehensive assessment of diet that describes lionfish as a generalist piscivore that preys on over 40 species of teleost comprising more than 20 families. Next, I use the histology of gonads to describe both oogenesis and reproductive dynamics of lionfish. Lionfish mature relatively early and reproduce several times per month throughout the entire calendar year off North Carolina and the Bahamas. To investigate predation, an important component of natural mortality, I assessed the vulnerability of juvenile lionfish to predation by native serranids. Juvenile lionfish are not readily consumed by serranids, even after extreme periods of starvation. Last, I used a stage-based, matrix population model to estimate the scale of control that would be needed to reduce an invading population of lionfish. Together, this research provides the first comprehensive assessment on lionfish biology and ecology and explains a number of life history and ecological interactions that have facilitated the unprecedented and rapid establishment of this invasive finfish. Future research is needed to understand the scale of impacts that lionfish could cause, especially in coral reef ecosystems, which are already heavily stressed. This research further demonstrates the need for lionfish control strategies and more rigorous prevention and early detection and rapid response programs for marine non-native introductions.
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EXTRACT (SEE PDF FOR FULL ABSTRACT): Past work has shown that surface zonal equatorial wind stress, zonally integrated from one side of the Pacific to the other, is the key variable for estimating long-term El Niño behavior in the eastern Pacific. ... We used detrended COADS pressure in the eastern and western equatorial Pacific and post-1960 detrended Florida State University equatorial wind stress zonally averaged across the Pacific to verify this relationship.
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A novel peptide inhibitor (OGTI) of serine protease with a molecular weight of 1949.8, was purified from the skin secretion of the frog, Odorrana grahami. Of the tested serine proteases, OGTI only inhibited the hydrolysis activity of trypsin on synthetic chromogenic substrate. This precursor deduced from the cDNA sequence is composed of 70 amino acid residues. The mature OGTI contains 17 amino acid residues including a six-residue loop disulfided by two half-cysteines (AVNIPFKVHFRCKAAFC). In addition to its unique six-residue loop, the overall structure and precursor of OGTI are different from those of other serine protease inhibitors. It is also one of the smallest serine protease inhibitors ever found. (C) 2008 Elsevier Masson SAS. All rights reserved.
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Studies on the nutrient composition of smoked-dried Clarias gariepinus were carried out, to assess the effects of pest infestation on the dried catfish from two different market (Abakpa and Kpirikpiri market) area in Abakaliki Metropolis, Ebonyi State, Nigeria. Fish samples from the two markets where kept for pest to infest it and it were taken to Biochemistry Laboratory of Food Science and Technology in Ebonyi State University to assess the damage of pest on dried catfish using standard methods. There was a significant different among the mean weight of fish from the two markets (Abakpa and kpirikpiri; 19.13kg and 18.98kg respectively) compared with the mean weight of the control 20.09kg. There was a variation in the proximate composition of the fishes from the two markets compared with the control, the decreases of the proximate composition are: crude protein from 60.07% to 40.27%; fat from 8.35% to 5.90%; moisture content from 11.67% to 10.67; fiber from 12.93 to 11.93; ash from 4.02% to 3.54% and carbohydrate 12.67% to 5.89%. The longer the storage periods of the infested smoked fish the more the tissue was degraded. Proper handling and storage of dried catfish are required to prolong the shelf life and nutrient content of dried catfish.
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Bacterial lipoproteins (LP) are a family of cell wall components found in a wide variety of bacteria. In this study, we characterized the response of HUCL, a telomerase-immortalized human corneal epithelial cell (HCEC) line, to LP isolated from Staphylococcus (S) aureus. S. aureus LP (saLP) prepared by Triton X-114 extraction stimulated the activation of NF-kappa B, JNK, and P38 signaling pathways in HUCL cells. The extracts failed to stimulate NF-kappa B activation in HUCL cells after lipoprotein lipase treatment and in cell lines expressing TLR4 or TLR9, but not TLR2, indicating lipoprotein nature of the extracts. saLP induced the up-regulation of a variety of inflammatory cytokines and chemokines (IL-6, IL-8, ICAM-1). antimicrobial molecules (hBD-2, LL-37, and iNOS), and homeostasis genes (Mn-SOD) at both the mRNA level and protein level. Similar inflammatory response to saLP was also observed in primarily cultured HCECs using the production of IL-6 as readout. Moreover, TLR2 neutralizing antibody blocked the saLP-induced secretion of IL-6, IL-8 and hBD2 in HUCL cells. Our findings suggest that saLP activates TLR2 and triggers innate immune response in the cornea to S. aureus infection via production of proinflammatory cytokines and defense molecules. (C) 2007 Elsevier Ltd. All rights reserved.
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AMPS (Analysis of microelectronic and photonic structures) mode,which was developed by Pennsylvania State University, has been used to module the light J-V characteristics of a-Si solar cells with a structure of TCO/p-a-SiC:H/i-a-Si:H/n-a-Si:H/ metal. The effects of valence band offset and contact barriers at p/i and TOC/p, n/metal interfaces on the light J-V characteristics have been examined. The modeling has qualitatively categorized and explained the non-ideal J-V behaviors (rollover, crossover, Voc shift,and rollunder) observed in a-Si based solar cells.
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The effects of hydrogen passivation on multi-crystalline silicon (mc-Si) solar cells are reported in this paper. Hydrogen plasma was generated by means of ac glow discharge in a hydrogen atmosphere. Hydrogen passivation was carried out with three different groups of mc-Si solar cells after finishing contacts. The experimental results demonstrated that the photovoltaic performances of the solar cell samples have been improved after hydrogen plasma treatment, with a relative increase in conversion efficiency up to 10.6%. A calculation modelling has been performed to interpret the experimental results using the model for analysis of microelectronic and photonic structures developed at Pennsylvania State University.
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AMPS simulator, which was developed by Pennsylvania State University, has been used to simulate photovoltaic performances of nc-Si:H/c-Si solar cells. It is shown that interface states are essential factors prominently influencing open circuit voltages (V-OC) and fill factors (FF) of these structured solar cells. Short circuit current density (J(SC)) or spectral response seems more sensitive to the thickness of intrinsic a-Si:H buffer layers inserted into n(+)-nc-Si:H layer and p-c-Si substrates. Impacts of bandgap offset on solar cell performances have also been analyzed. As DeltaE(C) increases, degradation of VOC and FF owing to interface states are dramatically recovered. This implies that the interface state cannot merely be regarded as carrier recombination centres, and impacts of interfacial layer on devices need further investigation. Theoretical maximum efficiency of up to 31.17% (AM1.5,100mW/cm(2), 0.40-1.1mum) has been obtained with BSF structure, idealized light-trapping effect(R-F=0, R-B=1) and no interface states.
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Storage of raster metadata is a key topic in spatial database. Although there are a few of abstract standards on raster metadata, there is not implement standard about it. This paper concludes three storage models implemented in current spatial databases and discusses their advantages and disadvantages. After that analyzing, the paper proposes a mixed storage method which is used the relational table to store structured metadata and used XML to store non-structured metadata, and gives its implementation solution. © 2010 IEEE.
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Rossby波是地球物理流体动力学中非常重要的一种波动,海洋斜压长Rossby波在海洋动力过程中起着相当重要的作用。它维持并影响强西边界流,是海盆内能量传播的主要机制,它所携带的变异信号从大洋的东边界传播到内部,对海气耦合系统起到很重要的作用。热带印度洋是季风爆发的源地,对季风的年际变化具有重要影响。研究热带印度洋对理解季风变率和提高季风预测水平有重要的科学和应用价值。 本文利用TOPEX/Poseidon等高度计资料、美国国家海洋数据中心(NODC)的世界海洋图集(WOA05)长期气候态水文资料、美国Scripps海洋研究所的上层海温资料、中国Argo资料中心提供的Argo资料、美国国家环境预测中心(NCEP)的海表面温度、FSU(Florida State University)月平均风场和海气界面热通量等观测数据,全面分析了热带印度洋低频Rossby波的基本特征,并深入研究了低频Rossby波的生成机制及其对上层海洋热结构的影响。 采用相关分析等统计方法,结合1.5层约化重力模式,研究了热带南印度洋低频Rossby波的生成机制。结果表明: (1)热带南印度洋低频Rossby波分为东边界扰动产生的Rossby波和南印度洋中部风强迫Rossby波;东边界激发的为自由Rossby波,沿12°S波速大约13 cm/s,向西最远传播到80°E左右,之后被局地变量调整;强迫Rossby波在西传的过程中不断加强,波速较快,沿12°S能超过20 cm/s; (2)东边界扰动由印度尼西亚贯通流(ITF)导致的地转调整过程引起;内区风强迫Rossby波生成和加强的关键区为(70°E–95°E,15°S–5°S);显著的西传Rossby波同太平洋上的厄尔尼诺/南方涛动(ENSO)事件紧密相连,ENSO通过大气的遥驱动机制激发热带南印度洋低频Rossby波; (3)作为东边界低频变量扰动的一个重要因子,ITF的变化与ENSO事件密切相关,总的来讲,El Niño年ITF偏弱,La Niña年ITF偏强,这与前人的研究结果一致;但它在ENSO的不同位相时期,存在一定差异,并具有夏季锁相特征:El Niño事件发生年的春季到秋季,ITF偏强,夏季最强;从El Niño盛期(冬季)到次年秋季,ITF持续偏弱,夏季最弱。上述夏季锁相特征与夏季风的强弱变化相对应。La Niña期间情况相反。 西南印度洋(SWIO)(50°E–75°E,15°S–5°S)以及苏门答腊-爪哇沿岸地区是海表面高度异常(SSHA)和海表面温度异常(SSTA)相关显著的区域,表明内部海洋动力过程在次表层和表层变量的相互关系中起重要作用。本文以2006–2008年期间三个连续的同El Niño或者La Niña同时发生的正印度洋偶极子(IOD)事件为背景,基于Argo观测资料研究了表层和次表层IOD的演变以及二者的区别和联系,并首次采用垂直模态分解方法探讨了Rossby波对上层海洋热力结构影响的动力学特征,得到如下主要结论: (1)在热带印度洋,海洋动力过程一般主要由第一和第二低阶垂直斜压模态控制,而第一斜压模态处于主导地位——在SWIO海区,第一斜压模态运动的方差解释率为第二模态的2–3倍,在赤道和东南印度洋也达到2倍左右;另外,赤道印度洋地区高阶斜压模态运动对该地区的海洋动力过程也具有一定的贡献; (2)低频斜压Rossby波能影响海洋的垂直层结,尤其是强暖Rossby波使同第二斜压模态运动紧密相连的海洋上层层结减弱,加强第二斜压模态的贡献量,导致上层各等压线向下垂直位移增大,最终通过垂直混合过程调整上层海洋的热力结构;而低频斜压冷Rossby波会加强上层垂直层结,抑制该层内变量变化,因此第二斜压模态的贡献依然很小; (3)表层IOD和次表层IOD分布形态不同:表层东部冷异常主要集中在东南印度洋Sumatra-Java沿岸,次表层冷异常基本关于赤道对称;表层西部暖异常基本关于赤道对称,而在次表层赤道以南海温扰动强度远远大于赤道以北; (4)正IOD事件中,东南印度洋冷SSTA首先出现于Java沿岸,沿岸东南风引起的潜热释放增加以及沿岸上升流是该初始冷异常建立的主要机制,与之相关的SSTA东西梯度加强大气环流变化,并进一步强迫随后的海洋运动;1–2个月后,SST冷异常中心北跳到Sumatra沿岸并向西扩展,同时不断增强,其中Sumatra沿岸上升流、来自赤道印度洋的冷Kelvin波及其反射的西传冷Rossby波是这一演变过程的动力机制,而沿岸上升流起决定作用。
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Watt, D. (2006). Faith in the Landscape: Overseas Pilgrimages in 'The Book of Margery Kempe'. In C. Lees and G. Overing (Eds.), A Place to Believe In: Locating Medieval Landscapes (pp.170-187). University Park (PA): Pennsylvania State University Press. RAE2008
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Marggraf Turley, Richard, 'Johnny's in the Basement: Keats, Bob Dylan and Influence', In: 'The Monstrous Debt: Modalities of Romantic Influence in Twentieth Century Literature', (Detroit, MI: Wayne State University Press), pp.181-204, 2006 RAE2008
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Arizona State University Annual Religion Lecture: 1996
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Literature on the nonprofit sector focuses on charities and their interactions with clients or governmental agencies; donors are studied less often. Studies on philanthropy do examine donors but tend to focus on microlevel factors to explain their behavior. This study, in contrast, draws on institutional theory to show that macrolevel factors affect donor behavior. It also extends the institutional framework by examining the field‐level configurations in which donors and fundraisers are embedded. Employing the case of workplace charity, this new model highlights how the composition of the organizational field structures fundraisers and donors alike, shaping fundraisers’ strategies of solicitation and, therefore, the extent of donor control.