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41.
42.
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
43.
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
44.
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
45.
46.
Masae Shiyomi 《Population Ecology》1968,10(1):105-114
- It was shown in the previous report that the statistical model of the plant-to-plant movement of aphids could be fitted well to the actual population of barley aphids (Shiyomi , 1967). To examine validity of the model, results of the further experiments were analysed and the methods of estimation of parameters were given in this paper.
- Comparing the estimates of the parameters obtained by the moment method with those obtained by the maximum likelihood method, the estimates from the latter method were somewhat precise.
- The theoretical frequency distributions calculated from the model were fitted very well to the observed ones.
- The model was reexamined with reference to the results obtained byItô (1954, 1960). When the distance between plants was less than 4.5 cm, the farther was the distance between plants, the smaller was the rate of the plant-to-plant movement of aphids. When the distance was greater than 4.5 cm, however, the rate of the plant-to-plant movement was independent of the distance. This result is similar to that ofItô .
47.
Martin Granbom 《Journal of biological education》2016,50(2):185-195
This study shows that formative methods and increased student participation has a positive influence on learning measured as grades. The study was conducted during the course Biology A in a Swedish Upper Secondary School. The students constructed grade criteria and defined working methods and type of examination within a given topic, Gene technology. The procedure resulted in variation within teaching and examination carried out as an oral test in small groups. In the analysis, students’ grades on Gene technology were analysed in comparison with grades on other topics within the course, and the results show that mean grade is significantly higher on Gene technology. Based on the results and student course evaluations, I discuss the reasons behind the good results and the relation to participation, student interest, teacher and type of examination. 相似文献
48.
We applied the Cocktail method to a large data set of 4 117 relevés of all Slovak vegetation types with the aim to create
formalised definitions of all Slovakian mire plant associations. We defined 21 groups of species with the statistical tendency
of joint occurrences in vegetation. These groups differed substantially in their position along the pH/calcium gradient. We
further defined 24 plant associations according to presence and/or absence of certain groups and/or strong dominance of some
species. Only six traditional plant associations were not possible to be reproduced this way. We applied our formalised definitions
to the regional data set of mires from the surrounding of the Vysoké Tatry Mts. Combined with frequency-positive fidelity
index this method has led to the classification of the majority of vegetation plots into ten associations. When the vegetation
types obtained from Cocktail-based classification and from cluster analysis were compared with respect to measured pH and
conductivity in the study region, 82% of pairs differed significantly either in pH or in water conductivity in the former
classification and 69% in the latter one. 相似文献
49.
Xu Ke-xue 《植物分类学报:英文版》1993,31(6):578-586
The paper presented here is Concerned with the numerical cladisties. In
consideration of the fact that the parallel evolution has close relation to the length
of evolution graph, a new method of reconstructing evolutionary tree has been developed for the application and practice of cladistics.
The procedure of the algorithm of the new method presented in Table I is
similar to the method described in paper "An algorithm for cladistics method
of maximal same step length".
An essential step of the algorithm is how to decide the coefficient between two
cladistic units (CTUs). A coefficient called parallel evolutionary coefficient between
CTUp and CTUq is defined as follows:
where the j is code of CTU and the i is code of character; E(p, q, i, j) is a function given by following expression:
min (Xij, Xpj)+(Xij, Xqj)-2min(Xpj, Xqj) as Xij>min (Xpj, Xqj)
E(p,q, i,j ) =
0 otherwise.
where the Xij is the ith row (CTU) jth colunm (Character) element of the data
matrix.
Because the method of minimal parallel evolution is closely related to the
length of evolutionary graph, it is superior to the method of maximal same step
length. A simple datum as an example for comparison shows that the method of
minimal parallel evolution can arrive at a better result.
But in some cases, we may combine one method with another and thus the
coefficient should take following form:
S(Sij)=M·S (C) ij-N·S(P) ij
in which S (C) ij and S (P) ij are the same step coefficients and the parallel evolution coefficient respectively, and the M and N are positive integers as a weightnumber being given in advance. 相似文献
50.
用Braun-B1anquet法对西湖山区植被的132个样地进行了群落的分类。初步确定了2个 群丛(木荷群丛与黄连木群丛)、7个亚群丛和6个变型;并对28个鉴别种组进行了分析,它们都较好地反映了群落分类单位的特征和生境条件特点以及植被在空间分布上的连续性变异。 相似文献