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1.
Our review of existing approaches and regulatory uses of weight-of-evidence (WOE) methods suggested the need for a practical strategy for deploying WOE within a predictive ecological risk assessment (ERA). WOE is the process of considering strengths and weaknesses of various pieces of information in order to inform a decision being made among competing alternatives. A predictive ERA uses existing information relating cause and effect to estimate the probability that today's action X will lead to tomorrow's adverse outcome Y. There appears to be no practical guidance for use of WOE in predictive assessments. We therefore propose a strategy for using a WOE approach, within an ERA framework, to weigh and integrate outcomes from various lines of evidence to estimate the probability of an adverse outcome in an assessment endpoint. An ERA framework is necessary to connect the results of an assessment to the management goals of concern to decision-makers and stakeholders. Within that framework, a WOE approach provides a consistent and transparent means of interpreting the myriad types of data and information gathered during a complex ecological assessment. Impediments to application of WOE are discussed, including limited regulatory guidance, limited prior regulatory use, and persistent reliance on threshold-based decision-making.  相似文献   

2.
Redrobe JP  Dumont Y  Quirion R 《Life sciences》2002,71(25):2921-2937
Neuropeptide Y (NPY) is widely distributed throughout the central nervous system (CNS) and is one of the most conserved peptides in evolution, suggesting an important role in the regulation of basic physiological functions. In addition, both pre-clinical and clinical evidence have suggested that NPY, together with its receptors, may have a direct implication in several psychiatric disorders, including depression and related illnesses. NPY-like immunoreactivity and NPY receptors are expressed throughout the brain, with varying concentrations being found throughout the limbic system. Such brain structures have been repeatedly implicated in the modulation of emotional processing, as well as in the pathogenesis of depressive disorders. This review will concentrate on the distribution of NPY, its receptors, and the putative role played by this peptide in depressive illness based on both pre-clinical and clinical evidence.  相似文献   

3.
Several developments in science education aim to improve pupils' ability to ‘think scientifically’. This paper argues for the explicit teaching of the ideas that pupils need to ‘think about’ to do this; ideas related to the design of investigations and the collection, presentation, analysis, and evaluation of the resulting evidence — ideas which are important both for pupils who continue to study or work with biology and for all pupils to become biologically literate. This paper considers some of the concepts of evidence which are particularly important to biology, and discusses how and why the ideas could be taught.  相似文献   

4.
新种祁门过路黄的核型证据   总被引:2,自引:0,他引:2  
邵剑文  张小平   《广西植物》2006,26(1):58-62
对新种祁门过路黄及其近缘种巴东过路黄和光叶巴东过路黄的核型在居群水平上进行了比较研究。结果表明这两种植物的核型特征在种内是稳定的,同一物种的不同居群间核型无明显差异。祁门过路黄的核型为2n=2x=24=6m+6sm+6st+6t;巴东过路黄和光叶巴东过路黄的核型均为2n=2x=24=6m+4sm+6st+8t;两物种间核型差异显著,核型特征支持将祁门过路黄作为新种处理。  相似文献   

5.
The simple conductivity method described here uses a home-made electrode for determining the salinity of estuarine waters  相似文献   

6.
朱新宇  张瑶  周鸣鸣 《遗传》2005,27(6):1020-1024
顶复合器门的原生动物(Apicomplexan protozoa)含有一个高度退化的质体样(plastid-like)细胞器,定名为apicoplast。Apicoplast的进化起源是一个长期激烈争论的问题,尽管使用了多种分子技术,但尚未取得一致的结论,以致成为质体起源研究的典型案例。文章评述了apicoplast起源研究的分子证据,分析了新的分子证据的可能来源,为进一步研究提供线索。  相似文献   

7.
Curran JM  Robertson B  Vignaux GA 《Genetica》1999,105(2):211-213
In a recent article Levine and Kobilinsky (1997) point out that current methods in forensic DNA 'identification' are inadequate because the commercial kits commonly used in forensic practice do not detect the true genotype, but rather a genotype based on convenient categorization. For this reason, Levine and Kobilinsky argue that statistics attached to such categorizations are invalid. The authors believe that the arguments of Levine and Kobilinsky are logically flawed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

8.
李佳 《现代生物医学进展》2012,12(12):2379-2381
宽恕作为人类所独有一种美德,对人们来说并不陌生,但对于宽恕的系统研究却仅始于上个世纪80、90年代。本文采用文献法着重从生理心理、神经证据等方面对宽恕认知神经科学方面的研究进行了梳理和整合,最后对该研究领域未来的发展方向进行了展望。  相似文献   

9.
淡水龟科是龟鳖目中物种数目最多、形态变异最多样的一个类群。其早期的系统学研究主要依据形态学和细胞学的特征,近年来,随着分子数据的不断增多,结合形态学等方法,淡水龟科系统发生学研究取得了诸多进展,但至今尚未有一致的结论。本文主要对近年来有关淡水龟科起源的单系性问题;潮龟属、闭壳龟属和拟水龟属重划分问题;潮龟属、草龟属和小棱背龟属属间关系问题;齿缘龟属、果龟属和东方龟属属间关系问题;齿缘龟属和木纹龟属属内种间关系问题研究进行了文献综述,以期为淡水龟科的系统发生关系和物种保护等研究提供参考。  相似文献   

10.
Scanning probe acoustic microscopy (SPAM) has been successfully used to study inorganic and keratin biomaterials. However, few studies have attempted to apply SPAM to structural study of non-keratin organic materials such as starch based materials. This study investigated hardness and surface finish to establish sample preparation method suitable for SPAM imaging and acquired clear acoustic images of extruded starch materials. Acquired acoustic images directly exhibited certain structure of starch materials and provided visual evidence of starch material components and aggregates. In addition, through correlating acoustic images with X-ray diffraction data, crystal-structural information in nano-scale was obtained and acoustic image contrast showed a linear relationship with starch amylose content in extruded starch materials.  相似文献   

11.
12.
13.
We used a data matrix of 65 morphological characters from 25 ingroup and 6 outgroup taxa, and an alignment comprising complete 18S rDNA sequences from 82 species of parasitic and free-living Platyhelminthes and from 19 species of lower invertebrates to analyse phylogenetic relationships of various platyhelminth taxa. Of the 1358 unambiguously alignablc molecular positions, 995 were variable and 757 were phylogenctically informative (parsimony criterion); complete 18S rDNA sequences ranged in length from 1755 to 2873 bp. Main conclusions are: Ncodermata are monophylctic, and the Trematoda, Monogenca and Cestoda within them are monophylctic as well. The sister group of the Ncodermata is all the other Ncoophora; the Kalyptorhynchia, Typhloplanida, Dalyelliida and Tcmnocephalida form one clade, and the last three another. Monophyly of the Seriata is rejected, but Polycladida/ Macrostomida/Haplopharyngida are monophylctic, as arc the last two taxa. As a consequence, validity of the taxon Trepaxonemata is rejected. Further studies must show the correct position of the Acocla and Nemertodermatida. It is stressed that morphological and molecular data in some respects lead to contradictory results, for instance concerning the position of the Fecampiidac/ Urastoma/Ichthyophaga and the relative position of the Lccithoepitheliata. Denser sampling of taxa for molecular data, complementary sequences from independent genes, and inclusion of additional morphological data are necessary to resolve these contradictions.  相似文献   

14.
Chen J  Jiang LY  Qiao GX 《ZooKeys》2011,(111):11-18
The taxonomic position of Hormaphis similibetulae Qiao & Zhang, 2004 has been reexamined. The phylogenetic position of Hormaphis similibetulae was inferred by maximum parsimony, maximum likelihood and Bayesian analyses on the basis of partial nuclear elongation factor-1α and mitochondrial tRNA leucine/cytochrome oxidase II sequences. The results showed that this species fell into the clade of Hamamelistes species, occupying a basal position, and was clearly distinct from other Hormaphis species. A closer relationship between Hormaphis similibetulae and Hamamelistes species was also revealed by life cycle analysis. Therefore, we conclude that Hormaphis similibetulae should be transferred to the genus Hamamelistes as Hamamelistes similibetulae (Qiao & Zhang), comb. n.  相似文献   

15.
We suggest that there are six fundamental characteristics of causation: time order, co-occurrence, preceding causation, sufficiency, interaction, and alteration. The cause precedes the effect (time order). The cause co-occurs with the unaffected entity in space and time (co-occurrence). Causes and their effects are the result of a web of causation (preceding causation). The intensity, frequency, and duration of the cause are adequate and the susceptible entity can exhibit the type and magnitude of the effect (sufficiency). The cause effectively interacts with the entity in a way that induces the effect (interaction). And, the entity is changed by the interactions with the cause (alteration). In contrast to Hill's criteria, the causal characteristics are distinct from the: (1) evidence that is used to document causal characteristics, (2) sources of information used to develop the evidence, and (3) qualities used to evaluate evidence of causal characteristics and body of evidence for the causal relationship. Evidence of causal characteristics can form the basis for assessments of epidemiological studies and can structure an explanatory narrative that is causally relevant and substantive. Six core characteristics may be easier to organize, evaluate, communicate, and for decision-makers to assimilate, remember, and inspire action.  相似文献   

16.
Argumentation in science is the process of coordinating theory and evidence to justify conclusions. This practice is at the heart of scientific journal writing and communication, but little is known regarding the argument quality of college science majors, the future scientists. Studies on written arguments at the college level have focused primarily on non-majors and upper-level students. To investigate and describe these skills throughout the biology curriculum, majors (n = 243) in four levels of undergraduate biology courses at a public university were assessed using a short, written argument instrument based on a hypothetical data set and scenario. Using Toulmin’s argumentation pattern to assess the instruments for argument aspects and quality, very few differences were found in the scores across course levels. Students were able to generate simple arguments consisting of claim, evidence and reasoning. The ability to provide scientific principles as reasoning to connect evidence and claims was positively correlated with course level. However, advanced argumentation skills, such as creating alternative explanations and rebuttals, were lacking across all course levels. These findings imply the need for explicit attention to argument construction throughout the undergraduate biology curriculum.  相似文献   

17.
Abstract The Tibetan migratory locust (Locusta migratoria tibetensis Chen) is the highest altitude distributed subspecies among the 10 subspecies of migratory locusts. It was discovered and described as new subspecies in 1963. It is mostly distributed above an elevation of 3 000 m, with the highest up to 4 600 m, on the “Roof of the World,” viz. the Qinghai-Xizang Plateau in southwestern China. Recent study on the historic literature revealed ancient records of locust plagues caused by Locusta migratoria tibetensis Chen in many regions of Xizang (Tibet). These disasters took place during 124 years stretching from 1828 to 1952. Forty-five places were infested by locust swarms, and from 1846 to 1857 locust disasters occurred sucessively in 12 years, and affected 18 places of Xizang. At the severe disaster regions crops were damaged by locusts in such a degree that there was no harvest at all. At the same time, locust plagues due to another subspecies also occurred in the plains between the Yellow River and Huaihe and Haihe Rivers in East China. The disasters in Xizang were caused by the Tibetan migratory locust, while in Huang-Huai-Hai Plain disasters were due to the Oriental migratory locust Locusta migratoria manilensis (Meyen). This study not only provides the evidence that the Tibetan migratory locust has been existing as a separate subspecies with a long history, but also reveals the relevant years of locust plagues, their regional distribution and intermittent rules of locust plagues. It also offers a scientific basis for forecasting Tibetan migratory locust disasters and related monitoring strategies; as well as understanding the close relationship between the outbreak of the migratory locust and drought.  相似文献   

18.
19.
The recent award by an arbitral tribunal in a case brought by the Philippines against China gives lawyers reason to reexamine the historical evidence put forward by claimants in the South China Sea disputes. While the Tribunal was barred from considering territorial or boundary questions, it did cast doubt on the historical narrative rule that China has asserted in support of its claims. Fresh evidence from other sources also suggests that discussions of these matters need to move beyond arguments put forward in a small number of papers published more than thirty years ago. A close examination of the references used in those papers shows that they relied upon highly partisan Chinese sources. Recent historical research has produced new facts about the development of the competing territorial claims in the South China Sea, but international legal discourse has yet to take these findings into account. This article examines some of the key works in the field and calls for them to be reassessed and for future discussion of the disputes to be based upon verifiable and contextualized evidence rather than on nationalist assertions.  相似文献   

20.
William C. Thompson 《Genetica》1995,96(1-2):153-168
This article discusses two factors that may profoundly affect the value of DNA evidence for proving that two samples have a common source: uncertainty about the interpretation of test results and the possibility of laboratory error. Three case studies are presented to illustrate the importance of the analyst's subjective judgments in interpreting some RFLP-based forensic DNA tests. In each case, the likelihood ratio describing the value of DNA evidence is shown to be dramatically reduced by uncertainty about the scoring of bands and the possibility of laboratory error. The article concludes that statistical estimates of the frequency of matching genotypes can be a misleading index of the value of DNA evidence, and that more adequate indices are needed. It also argues that forensic laboratoires should comply with the National Research Council's recommendation that forensic test results be scored in a blind or objective manner.Editor's commentsThe author treats the timely and important issue of laboratory error. Readers will need to read the paper by Lempert in this volume for an alternative interpretation of the 1989 proficiency testing of Cellmark diagnostics.  相似文献   

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