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排序方式: 共有334条查询结果,搜索用时 15 毫秒
1.
Tiffany M. Nuessle Nicole L. Garneau Meghan M. Sloan Stephanie A. Santorico 《Journal of visualized experiments : JoVE》2015,(100)
The goal of the Denver Papillae Protocol is to use a dichotomous key to define and prioritize the characteristics of fungiform papillae (FP) to ensure consistent scoring between scorers. This protocol builds off of a need that has arisen from the last two decades of taste research using FP as a proxy for taste pore density. FP density has historically been analyzed using Miller & Reedy’s 1990 characterizations of their morphology: round, stained lighter, large, and elevated. In this work, the authors forewarned that stricter definitions of FP morphology needed to be outlined. Despite this call to action, follow up literature has been scarce, with most studies continuing to cite Miller & Reedy’s original work. Consequently, FP density reports have been highly variable and, combined with small sample sizes, may contribute to the discrepant conclusions on the role of FP in taste sensitivity. The Genetics of Taste Lab explored this apparent inconsistency in counting and found that scorers were individually prioritizing the importance of these characteristics differently and had no guidance for when a papilla had some, but not all, of the reported qualities of FP. The result of this subjectivity is highly variable FP counts of the same tongue image. The Denver Papillae Protocol has been developed to remedy this consequence through use of a dichotomous key that further defines and prioritizes the importance of the characteristics put forth by Miller & Reedy. The proposed method could help create a standard way to quantify FP for researchers in the field of taste and nutritional studies. 相似文献
2.
Report cards are an increasingly popular method for summarising and communicating relative environmental performance and ecosystem health, including in aquatic environments. They are usually underpinned by an Ecosystem Health Index (EHI) that combines various individual indicators to produce an overall ecosystem health “score”. As a result of public water quality concerns, an integrated means of monitoring and reporting on aquatic ecosystem health was needed for the Fitzroy Basin in central Queensland, Australia. The Fitzroy Partnership for River Health was formed to address this need, and developed an EHI and report card for the Basin using existing monitoring data collected from various third parties including regulated companies operations and government. At 142,000 square kilometres, the Fitzroy Basin is the largest catchment draining to the World Heritage Listed Great Barrier Reef. The Fitzroy Basin provides an example of how to deliver an effective aquatic ecosystem health reporting system in a large and complex river basin. We describe the methodology used to develop an adaptive EHI for the Fitzroy Basin that addresses variability, complexity and scale issues associated with reporting across large areas. As well, we report how to manage the design and reporting stages given limitations in data collection and scientific understanding. 相似文献
3.
Summary A field experiment was conducted using15N-labelled urea on a Reddish Brown Lateritic (Peleustult) soil. Growing two crops on flat land and on soil ridges of 15 cm
height produced similar comparative effects from fertilizer on maize. However, fertilizer applied by broadcasting on maize
with a 50 cm effective band followed by incorporating was more useful to mungbean than that applied by banding below the cereal
seed rows when crops were grown on flat land. The reverse was observed when crops were grown on ridges. It was deduced that
the maize cultivar was not likely to affect comparative efficiencies of fertilizer.
For fertilizer application at sowing, broadcasting in 50 cm maize effective band followed by incorporating was slightly superior
to banding below maize seed rows. Side-dressing of fertilizer to maize at 4 weeks after sowing was superior to application
at sowing. Evenly-split application, at sowing and at 4 weeks after sowing, was either only slightly superior or comparable
to non-split application by banding below maize seed rows at sowing, depending on placement method of the first application.
Soil moisture status as a possible factor rendering discrepancy in the comparative efficiencies obtained by different authors
is discussed. 相似文献
4.
Benjamin Risse Nils Otto Dimitri Berh Xiaoyi Jiang Christian Kl?mbt 《Journal of visualized experiments : JoVE》2014,(94)
The analysis of neuronal network function requires a reliable measurement of behavioral traits. Since the behavior of freely moving animals is variable to a certain degree, many animals have to be analyzed, to obtain statistically significant data. This in turn requires a computer assisted automated quantification of locomotion patterns. To obtain high contrast images of almost translucent and small moving objects, a novel imaging technique based on frustrated total internal reflection called FIM was developed. In this setup, animals are only illuminated with infrared light at the very specific position of contact with the underlying crawling surface. This methodology results in very high contrast images. Subsequently, these high contrast images are processed using established contour tracking algorithms. Based on this, we developed the FIMTrack software, which serves to extract a number of features needed to quantitatively describe a large variety of locomotion characteristics. During the development of this software package, we focused our efforts on an open source architecture allowing the easy addition of further modules. The program operates platform independent and is accompanied by an intuitive GUI guiding the user through data analysis. All locomotion parameter values are given in form of csv files allowing further data analyses. In addition, a Results Viewer integrated into the tracking software provides the opportunity to interactively review and adjust the output, as might be needed during stimulus integration. The power of FIM and FIMTrack is demonstrated by studying the locomotion of Drosophila larvae. 相似文献
5.
Kyrylo A. Pyrshev Semen O. Yesylevskyy Alexander P. Demchenko 《Biochemical and biophysical research communications》2019,508(4):1139-1144
New technique of detecting lateral heterogeneity of the plasma membrane of living cells by means of membrane-binding fluorescent dyes is proposed. The kinetics of dye incorporation into the membrane or its lateral diffusion inside the membrane is measured and decomposed into exponential components by means of the Maximum Entropy Method. Two distinct exponential components are obtained consistently in all cases for several fluorescent dyes, two different cell lines and in different types of experiments including spectroscopy, flow cytometry and fluorescence recovery after photobleaching. These components are attributed to the liquid-ordered and disordered phases in the plasma membrane of studied cells in their dynamic equilibrium. 相似文献
6.
大尺度不透水面遥感估算方法比较——以京津唐为例 总被引:1,自引:0,他引:1
城市不透水面既是常用的城市化程度指标,也是衡量环境质量的重要指标。采用遥感技术准确提取城市不透水面并分析其空间扩张过程,对生态城市建设具有重要意义。基于Landsat 5 TM影像,采用NDVI二元法和线性光谱分解法,分别提取北京、天津和唐山3个城市不透水面信息,并将不透水面估算结果与近同期的ALOS影像提取结果对比验证。结果表明,线性光谱分解法获取的不透水面结果较好,RMSE为20.6%,能有效提取大范围的不透水面信息。 相似文献
7.
目的 构建符合广东省医疗卫生现状和特点的医师多点执业实施基本框架。方法 采用Delphi法对备选指标进行3轮专家咨询。结果 预调查和2轮咨询专家积极性系数分别为100%、96.67%、100%;专家的权威系数为0.70;正式两轮咨询一级指标权重权重比例接近,P<0.005 ;正式两轮咨询专家一致性系数分别为0.161、0.191。结合专家对指标评价总分的排序和各指标重要性、可操作性变异系数,最终筛选25个指标。结论 从公立医院的角度,构建了一个较为科学、合理的医师多点执业实施框架。 相似文献
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10.
Thomas C. Wanger Iris Motzke Samuel C. Furrer Barry W. Brook Bernd Gruber 《Ecological Research》2009,24(2):345-353
Rapid and reliable estimation of population size is needed for the efficient monitoring of animal populations of conservation
concern. Unfortunately, technical advances in this area have not been paralleled in uptake in conservation, which may be due
to difficulties in implementation or the lack of general guidelines for application. Here we tested five different methods
used to estimate population size [capture–mark–recapture (CMR), finite-mixture models, model averaging of finite-mixture models,
accumulation curve methods (ACM), and the line transect method (LT)] using extensive capture–recapture data of the giant day
gecko (Gekkonidae, Phelsuma madagascariensis grandis, Gray 1870) at the Masoala rainforest exhibit, Zurich Zoo. When the complete data were analyzed [30 sessions (and 27 sessions
for the LT)], all methods except the LT produced similar estimates of population size. The simple ACM gave a small coefficient
of variation (CV), but did not cover the most likely value of population size at moderate sampling effort. Nevertheless, the
ACM was the only method that showed a reasonable convergence when subsets of data were used. CMR and Pledger models included
the reference value in their confidence intervals (CI) after 25 and 30 sessions, respectively. Although model averaging did
slightly improve the estimate, the CV was still high for the full dataset. Our method of using subsets of data to test the
robustness of estimates is simple to apply and could be adopted more widely in such analyzes to evaluate sensitivity to method
of evaluation. In conclusion, simple accumulation methods showed similar efficiency to more complex statistical models, and
are likely to be sufficiently precise for most conservation monitoring purposes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献