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排序方式: 共有383条查询结果,搜索用时 15 毫秒
1.
Krystal Archer Zuzana Broskova Ahmed S. Bayoumi Jian-peng Teoh Alec Davila Yaoliang Tang Huabo Su Il-man Kim 《International journal of molecular sciences》2015,16(10):23651-23667
Cardiovascular disease is the leading cause of death in the United States, accounting for nearly one in every seven deaths. Over the last decade, various targeted therapeutics have been introduced, but there has been no corresponding improvement in patient survival. Since the mortality rate of cardiovascular disease has not been significantly decreased, efforts have been made to understand the link between heart disease and novel therapeutic targets such as non-coding RNAs. Among multiple non-coding RNAs, long non-coding RNA (lncRNA) has emerged as a novel therapeutic in cardiovascular medicine. LncRNAs are endogenous RNAs that contain over 200 nucleotides and regulate gene expression. Recent studies suggest critical roles of lncRNAs in modulating the initiation and progression of cardiovascular diseases. For example, aberrant lncRNA expression has been associated with the pathogenesis of ischemic heart failure. In this article, we present a synopsis of recent discoveries that link the roles and molecular interactions of lncRNAs to cardiovascular diseases. Moreover, we describe the prevalence of circulating lncRNAs and assess their potential utilities as biomarkers for diagnosis and prognosis of heart disease. 相似文献
2.
Evaluation of layout and atmospheric stability effects in wind farms using large‐eddy simulation 下载免费PDF全文
Niranjan S. Ghaisas Cristina L. Archer Shengbai Xie Sicheng Wu Eoghan Maguire 《风能》2017,20(7):1227-1240
Large‐eddy simulation (LES) has been used previously to study the effect of either configuration or atmospheric stability on the power generated by large wind farms. This is the first study to consider both stability and wind farm configuration simultaneously and methodically with LES. Two prevailing wind directions, two layouts (turbines aligned versus staggered with respect to the wind) and three stabilities (neutral and moderately unstable and stable) were evaluated. Compared with neutral conditions, unstable conditions led to reduced wake losses in one configuration, to enhanced wake losses in two and to unchanged wake losses in one configuration. Conversely, stable conditions led to increased wake losses in one, decreased wake losses in two and unchanged wake losses in one configuration. Three competing effects, namely, rates of wake recovery due to vertical mixing, horizontal spread of wakes and localized regions of acceleration caused by multiple upstream wakes, were identified as being responsible for the observed trends in wake losses. The detailed flow features responsible for these non‐linear interactions could only be resolved by the LES. Existing analytical models ignore stability and non‐linear configuration effects, which therefore need to be incorporated. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
3.
4.
Cora-Costanze Sommerey Tim L. WilliamsIan McCrone Aran Ruiz-FerrerasDan Freeman Joy Archer 《Journal of dairy science》2014
Thromboelastography is a whole blood-based coagulation assay that can be used to investigate hypocoagulability and hypercoagulability, as seen with thromboembolic diseases and disseminated intravascular coagulation. Numerous coagulopathies due to different causes are reported in cows. The objective was to establish reference intervals for thromboelastography using the TEG 5000 (Haemonetics GmbH, Munich, Germany) with citrated whole blood samples and kaolin activation in dairy cows and to investigate possible thromboelastographic changes between cows in different lactation periods. An additional objective was to test the stability of samples for up to 100 h. Sixty blood samples from healthy Holstein-Friesian cows were examined. The samples were allocated to 3 different lactation groups (≤30 d postcalving, 31–99 d postcalving, ≥100 d postcalving). Thromboelastography was performed by using the TEG 5000 analyzer with citrated whole blood samples with kaolin activation. The calculated reference intervals were as follows: reaction time = 2.2 to 6.2 min, coagulation time = 0.8 to 2.0 min, angle α = 58.2 to 81.8°, maximum amplitude = 64.3 to 89.2 mm, and clot rigidity = 9.2 to 41.2 dyn/cm2. The 3 different lactation groups showed no significant differences in TEG parameters. No significant difference was seen in samples stored for up to 48 h at room temperature, which indicates that delays in processing samples, such as those arising during transit, are not an issue. 相似文献
5.
Few naturalistic studies have been carried out with commuter cyclists to discover the types of problems they encounter on a daily basis. The study presented here has been commissioned by the City of Stockholm municipality and focuses specifically on commuter cyclists in the Greater Stockholm area. The aim of the study was to describe and pinpoint accessibility and safety problems, but also to generate an accessible geographical interface that could serve as a traffic planning tool for cycle network improvement. Statistical surveys in the Stockholm area have shown a rapid growth in the number of cyclists as well as an increase in problems associated with an overburdened cycle infrastructure. Given the heightened emphasis on transport system sustainability, the City of Stockholm is faced with the challenging task of trying to maintain and encourage the upward trend in commuter cycling through a process that involves problem identification, classification, prioritisation and resolution. An innovative methodology involving the use of GPS logging devices and small video cameras was developed and supported with analysis software designed specifically for the purposes of this study. Experienced commuter cyclists were recruited to cycle 17 different major cycle routes to and from the suburbs and inner city area during morning and afternoon peak traffic hours during the main cycle season. Over 500 safety and accessibility/mobility problems were identified and recorded from the data collected from 16 commuter cyclists. The method and representation of data proved successful for strategic traffic planning work at City of Stockholm and has since provided invaluable input for and the development of a new cycle plan for Greater Stockholm. Indirectly, the results of this work have also contributed to longer term safety and environmental targets. 相似文献
6.
Impedance spectroscopy of bismuth sodium titanate: Barium titanate ceramics with manganese doping 下载免费PDF全文
V. Hugo Schmidt Noah Archer Chi‐Shun Tu 《Journal of the American Ceramic Society》2018,101(2):713-722
In this work we use Impedance Spectroscopy (IS) to study lead‐free ceramics of perovskite structure (Bi1/2Na1/2TiO3)0.925(BaTiO3)0.075 with Mn doping of 0, 0.2, 1.0, and 2.0 at.%. We compare our IS results with permittivity results, using dielectric to resistivity transformation equations which allow us to display results either as permittivity or as resistivity. We observe ionic conductivity dominating at lower temperatures, giving way to electronic conductivity at higher temperatures. The permittivity shows deviations from Curie‐Weiss behavior characteristic of relaxor ferroelectrics. The 0.2% Mn samples show the highest ionic resistivity, which will reduce heating for high voltage piezoelectric applications. They also have the highest Curie‐Weiss temperature and Burns temperature. 相似文献
7.
Florian Zink Hamish Waterer Rosalind Archer Laura Schaefer 《International Journal of Thermal Sciences》2009,48(12):2309-2322
This work illustrates the optimization of thermoacoustic systems, while taking into account thermal losses to the surroundings that are typically disregarded. A simple thermoacoustic engine is used as an example for the methodology. Its driving component, the thermoacoustic regenerator (also referred to as the stack), is modeled with a finite element method and its dimensions are varied to find an optimal design with regard to thermal losses. Thermoacoustic phenomena are included by considering acoustic power, and viscous and capacitive losses that are characteristic for the regenerator. The optimization considers four weighted objectives and is conducted with the Nelder–Mead Simplex method. When trying to minimize thermal losses, the presented results show that the regenerator should be designed to be as short as possible. It was found that there is an optimal regenerator diameter for a given length. The results are presented for a variety of materials and weights for each objective. 相似文献
8.
In 2008, the UK launched the first regulatory sustainability reporting scheme for biofuels. The development of the scheme, managed by the Low Carbon Vehicle Partnership for the Department for Transport, involved extensive stakeholder engagement. The scheme has significantly increased understanding by policy-makers, the biofuels industry and its supply chains on how to monitor and manage the sustainability risks of biofuels and increase their greenhouse-gas benefits. It is providing a practical model for similar developments globally. To receive certificates in order to meet volume obligations under the Renewable Transport Fuel Obligation (RTFO), suppliers must provide a monthly carbon and sustainability report on individual batches of renewable fuels they supply into the UK. The Renewable Fuels Agency produces aggregate monthly reports of overall performance and quarterly updates of individual supplier performance. This scheme is an important first step to assist the biofuels industry to demonstrate its environmental credentials and justify the subsidies received. The paper provides a case study of the development of the scheme, its initial outcomes and outstanding challenges. 相似文献
9.
Robert Archer 《数字社区&智能家居》2010,(3):88-92
纵观当下的音视频市场,各种产品呈花齐放的态势,但功能上的差别却让不同的产品又各有优势。为了给大家提供一个选购依据,本文特挑选部分优秀音视频产品供大家参考。 相似文献
10.
This study investigates two methods of transforming intermittent wind electricity into firm baseload capacity: (1) using electricity from natural gas combined-cycle (NGCC) power plants and (2) using electricity from compressed air energy storage (CAES) power plants. The two wind models are compared in terms of capital and electricity costs, CO2 emissions, and fuel consumption rates. The findings indicate that the combination of wind and NGCC power plants is the lowest-cost method of transforming wind electricity into firm baseload capacity power supply at current natural gas prices (∼$6/GJ). However, the electricity supplied by wind and CAES power plants becomes economically competitive when the cost of natural gas for electric producers is $10.55/GJ or greater. In addition, the Wind-CAES system has the lowest CO2 emissions (93% and 71% lower than pulverized coal power plants and Wind-NGCC, respectively) and the lowest fuel consumption rates (9 and 4 times lower than pulverized coal power plants and Wind-NGCC, respectively). As such, the large-scale introduction of Wind-CAES systems in the U.S. appears to be the prudent long-term choice once natural gas price volatility, costs, and climate impacts are all considered. 相似文献