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Population‐based study of hospital costs for hospitalizations of infants,children, and adults with a congenital heart defect,Arkansas 2006 to 2011 下载免费PDF全文
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The performance of a supercapacitor can be characterized by a series of key parameters, including the cell capacitance, operating voltage, equivalent series resistance, power density, energy density, and time constant. To accurately measure these parameters, a variety of methods have been proposed and are used in academia and industry. As a result, some confusion has been caused due to the inconsistencies between different evaluation methods and practices. Such confusion hinders effective communication of new research findings, and creates a hurdle in transferring novel supercapacitor technologies from research labs to commercial applications. Based on public sources, this article is an attempt to inventory, critique and hopefully streamline the commonly used instruments, key performance metrics, calculation methods, and major affecting factors for supercapacitor performance evaluation. Thereafter the primary sources of inconsistencies are identified and possible solutions are suggested, with emphasis on device performance vs. material properties and the rate dependency of supercapacitors. We hope, by using reliable, intrinsic, and comparable parameters produced, the existing inconsistencies and confusion can be largely eliminated so as to facilitate further progress in the field. 相似文献
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Early Vaginal Opening in Juvenile Female Rats Given BRAF‐Inhibitor Dabrafenib Is Not Associated with Early Physiologic Sexual Maturation 下载免费PDF全文
Lorraine M. Posobiec Justin D. Vidal Angela Hughes‐Earle Susan B. Laffan Timothy Hart 《Birth defects research. Part B, Developmental and reproductive toxicology》2015,104(6):244-252
Dabrafenib (DAB), an inhibitor of BRAF kinase activity, is approved for metastatic melanoma with a BRAF V600E mutation. In support of pediatric cancer development, a nonclinical juvenile rat toxicity study was conducted in which females had early vaginal opening (VO). It was hypothesized that the early VO was not indicative of sexual maturation, but a result of a local effect on the vagina. An investigative study was conducted that mimicked the definitive study design, with rats given DAB or vehicle orally from Postnatal Day (PND) 7 to 35 and with necropsy subsets just before VO, at the first and second estrus, along with age‐matched controls. Histopathology was performed on reproductive tissues, including immunohistochemistry for BRAF expression. VO occurred earlier in DAB females than in controls (PND 27.2 vs. 31.5); however, the timing of the first estrus was unaffected (PND 34.0 vs. 33.0). DAB‐treated females evaluated just before VO (PND 22.0) had mostly immature reproductive tracts with no evidence of ovulation, similar to age‐matched controls; however, DAB‐treated females had keratinized and histologically open vaginas. Also, there was raised skin around the urogenital area, which correlated with hyperplasia/keratosis of the vulvar skin and keratinization of the distal vagina. BRAF expression (evaluated in controls) was localized to these tissues. Thus, early VO in rats given DAB likely represents a local effect accelerating vaginal keratinization to become open and not accelerated sexual maturation 相似文献
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《Harmful algae》2015
Nearly annual blooms of the marine dinoflagellate Karenia brevis, which initiate offshore on the West Florida Shelf in oligotrophic waters, cause widespread environmental and economic damage. The success of K. brevis as a bloom-former is partially attributed to its ability to use a diverse suite of nutrients from natural and anthropogenic sources, although relatively little is known about the ability of K. brevis and the closely related Karenia mikimotoi to use a variety of organic sources of phosphorus, including phosphomonoesters, phosphodiesters, and phosphonates. Through a series of bioassays, this study characterized the ability of axenic and nonaxenic K. brevis and K. mikimotoi clones isolated from Florida waters to use a variety of organic phosphorus compounds as the sole source of phosphorus for growth, comparing this utilization to that of inorganic sources of phosphate. Differing abilities of axenic and nonaxenic K. brevis and K. mikimotoi cultures to use phosphorus from the compounds evaluated were documented. Specifically, growth of axenic cultures was greatest on inorganic phosphorus and was not supported on the phosphomonoester phytate, or generally on phosphodiesters or phosphonates. The nonaxenic cultures were able to use organic compounds that the axenic cultures were not able to use, often after lags in growth, highlighting a potential role of co-associated bacterial communities to transform nutrients to bioavailable forms. Given the ability of K. brevis and K. mikimotoi to use a diverse suite of inorganic and organic phosphorus, bloom mitigation strategies should consider all nutrient forms. 相似文献
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温度对金银花尺蠖幼虫取食量及食物利用效率的影响 总被引:1,自引:0,他引:1
在室内研究不同温度(19℃、22℃、25℃、28℃和31℃)对金银花尺蠖幼虫取食量、取食速率、近似消化力和食物利用率的影响。结果表明,较低温度(19℃和22℃)时金银花尺蠖幼虫的取食量和取食速率比较小,近似消化力和食物利用率比较低,随着温度的升高,金银花尺蠖幼虫的取食量、取食速率、近似消化力和食物利用率均逐渐增大,到25℃时达到最大,分别为607.36 mg、27.47 mg/d、58.45%、20.81%;高温(31℃)时取食量明显减少,取食速率、近似消化力和食物利用率明显降低。根据所建立的平均取食量、取食速率、近似消化力、食物利用率与温度间的回归模型计算得出,金银花尺蠖幼虫取食量、取食速率、近似消化力和食物利用率最大的最适温度分别为26.15℃、25.02℃、25.38℃和25.30℃。 相似文献
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鸟类的资源分配和生活史策略 总被引:5,自引:0,他引:5
PatMONAGHAN 《动物学报》2004,50(6):942-947
本文综述了对资源分配理论的研究。使用了对小黑背鸥和红嘴山鸦的研究 ,表明卵产生中的资源分配和相关的生活史策略对个体发育和长期适合度有多方面的影响 ,对于种群存活有重要意义 相似文献
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