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961.
Cunningham JP 《Journal of evolutionary biology》2012,25(2):244-251
Evolutionary theory predicts that herbivorous insects should lay eggs on plants in a way that reflects the suitability of each plant species for larval development. Empirical studies, however, often fail to find any relationship between an adult insect's choice of host-plant and offspring fitness, and in such cases, it is generally assumed that other 'missing' factors (e.g. predation, host-plant abundance, learning and adult feeding sites) must be contributing to overall host suitability. Here, I consider an alternative theory - that a fitness cost inherent in the olfactory mechanism could constrain the evolution of insect host selection. I begin by reviewing current knowledge of odour processing in the insect antennal lobe with the aid of a simple schematic: the aim being to explain the workings of this mechanism to scientists who do not have prior knowledge in this field. I then use the schematic to explore how an insect's perception of host and non-host odours is governed by a set of processing rules, or algorithm. Under the assumptions of this mechanistic view, the perception of every plant odour is interrelated, and seemingly bad host choices can still arise as part of an overall adaptive behavioural strategy. I discuss how an understanding of mechanism can improve the interpretation of theoretical and empirical studies in insect behaviour and evolution. 相似文献
962.
iFlora是依据传统植物分类学及相关学科的研究基础,融入现代DNA测序技术,应用高速发展的信息、网络技术及云计算分析平台,收集、整合和管理植物物种相关信息,以建成智能物种鉴定和数据提取的开放应用系统(智能装备)。通过与该系统的双向交流,一方面,可以不断整合新的数据和技术充实iFlora的内容和功能;另一方面,可以通过该系统的多种鉴定途径实现快速、准确和方便的物种鉴定,获取所需物种的相关信息,满足专业机构和公众对物种和生物多样性的认知要求。本文重点介绍了构成iFlora的应用装置和支撑该装置的实物库(凭证标本、分子材料和DNA库)的建设及其重要性;阐述了构成iFlora各单元的高度整合和集成的特点,以及基于计算机技术的物种信息数字化和开放的云计算数据分析处理服务平台的枢纽作用;并讨论了iFlora创建过程所面临的困难和挑战,以及拟研发的智能装备的框架和应用前景。 相似文献
963.
新一代植物志:iFlora 总被引:2,自引:0,他引:2
进入21世纪,随着分子生物学及计算机信息等技术的快速发展,人们认知自然的手段和方式发生了根本性的变化。在现有电子植物志(eFlora)的基础上,融入新一代测序技术、DNA条形码数据、地理信息数据和计算机信息技术等新元素的新一代植物志(iFlora)应运而生。iFlora是通过系列关键技术的集成和攻关,构建便捷、准确识别植物和掌握相关数字化信息的新一代植物志(或智能装备),它将极大地促进植物分类学和系统发育、演化生物学、生态学、生物地理学和保护生物学等相关学科的发展,有效地服务于生物多样性保护和生物资源可持续利用、国家生态安全和社会公共教育等,并进一步提升公众对生物多样性的认识。iFlora的实施,将为培育和拓展物种识别圈(taxasphere)和生物文化圈(bioliterate world)做出应有的贡献,并可能成为引领国际植物学发展新的生长点。 相似文献
964.
心电检查网络平台近年来是医院信息化建设的热点,我院根据医院实际情况,分析了部署心电网络时涉及到的网络结构、数据交换、数据格式等实际问题,并成功实施了该项目。 相似文献
965.
Melatonin, which is a substance produced by the pineal body in vertebrates, inhibited regeneration in the planarian Dugesia japonica japonica Ichikawa et Kawakatsu. When decapitated planarians were maintained in a 1 mmol dm–3 solution of melatonin, formation of the head was retarded; formation of the eyes, however, was not disturbed. Similarly in animals from which the tail was cut, regeneration of the tail was retarded if the animals were kept in melatonin solution of 1 mmol dm–3. The effect was reversible once the melatonin was removed. Retardation of regeneration did not occur with similar application of three melatonin derivatives, serotonin hydrochloride, N-acetylserotonin, and 6-hydroxymelatonin. Melatonin endogenous to the planarian could be demonstrated by means of radio-immunoassay and was more abundant in the head region than other regions of the body. Melatonin, thus, appears to play a role in regulating regeneration in planarians and conceivably provides positional information in that process. 相似文献
966.
The authors present preliminary study in pursuance of developing a flow network-based methodology of building performance evaluation, as current efficiency-centered methods do not fully account for the complex building performance in which nature, economy, and humans are inseparably involved. Based on the principle of entropy, this study defines building as a thermodynamic system that networks useful resources―energy, material and information―through close interconnection with the global environment. Measures of information content in energy-flow networking and ecological performance indicators from Shannon’s information theory, Ulanowicz’s ascendency principle, and Odum’s maximum empower principle are discussed and integratively applied to developing a generic building performance evaluation model. For the holistic indication of building sustainability, this work attempts to reconcile Ulanowicz’s and Odum’s statements about ecosystem development and also integrates emergy (spelled with an “m”) and information metrics. Environmental behaviour of the building model was tested with simulation to validate consistency with system-level principles. Results reveal that network complexity corresponds to system power and resilience (L) and fitness (F) tend to peak at an intermediate level of efficiency. This finding demonstrates applicability of Odum’s maximum power principle to building study, suggesting that increasing complexity (and power) of emergy-flow networking be a fundamental characteristic of sustainable building performance. 相似文献
967.
Protein phosphorylation is one of the essential posttranslation modifications playing a vital role in the regulation of many fundamental cellular processes. We propose a LightGBM-based computational approach that uses evolutionary, geometric, sequence environment, and amino acid-specific features to decipher phosphate binding sites from a protein sequence. Our method, while compared with other existing methods on 2429 protein sequences taken from standard Phospho.ELM (P.ELM) benchmark data set featuring 11 organisms reports a higher F1 score = 0.504 (harmonic mean of the precision and recall) and ROC AUC = 0.836 (area under the curve of the receiver operating characteristics). The computation time of our proposed approach is much less than that of the recently developed deep learning-based framework. Structural analysis on selected protein sequences informs that our prediction is the superset of the phosphorylation sites, as mentioned in P.ELM data set. The foundation of our scheme is manual feature engineering and a decision tree-based classification. Hence, it is intuitive, and one can interpret the final tree as a set of rules resulting in a deeper understanding of the relationships between biophysical features and phosphorylation sites. Our innovative problem transformation method permits more control over precision and recall as is demonstrated by the fact that if we incorporate output probability of the existing deep learning framework as an additional feature, then our prediction improves (F1 score = 0.546; ROC AUC = 0.849). The implementation of our method can be accessed at http://cse.iitkgp.ac.in/~pralay/resources/PPSBoost/ and is mirrored at https://cosmos.iitkgp.ac.in/PPSBoost . 相似文献
968.
A digital data base was constructed by photo interpretation, mapping, and digitizing seven dates of aerial photography on the St. Marys River, Michigan, USA. The data base was used in conjunction with geographic information system software to examine historical changes in wetland area. Total wetland area between 1939 and 1985 ranged from 7 200 to 7 317 ha over a 46-year period of high and low water. There was greatest variation in areas of emergent wetland and scrub-shrub wetland, which appeared to be responding primarily to changes in water level. 相似文献
969.
Christian List Christian Elsholtz Thomas D. Seeley 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2009,364(1518):755-762
Condorcet''s jury theorem shows that when the members of a group have noisy but independent information about what is best for the group as a whole, majority decisions tend to outperform dictatorial ones. When voting is supplemented by communication, however, the resulting interdependencies between decision makers can strengthen or undermine this effect: they can facilitate information pooling, but also amplify errors. We consider an intriguing non-human case of independent information pooling combined with communication: the case of nest-site choice by honeybee (Apis mellifera) swarms. It is empirically well documented that when there are different nest sites that vary in quality, the bees usually choose the best one. We develop a new agent-based model of the bees'' decision process and show that its remarkable reliability stems from a particular interplay of independence and interdependence between the bees. 相似文献
970.
Hans-Dieter Pfannenstiel 《Development genes and evolution》1984,194(1):32-36
Summary Growth and regeneration of segments were recorded in the polychaeteOphryotrocha puerilis. In one experiment the ventral nerve cords (VNCs) of the animals were cut; in the other, VNCs were left intact. VNC lesion in some specimens resulted in the outgrowth of supernumerary posterior parts from the site of operation. The characteristics of outgrowth of these supernumeraries were essentially the same as in normal specimens without double tails. After removing different numbers of caudal setigers, each of the two tails of the same double-tail monster independently regenerated different segment numbers within a given time. A simple model is proposed, allowing for these results, which states that the larval body of a polychaete consists of two regions with completely different positional values (episphere — prostomium; hyposphere — pygidium). During growth, segments with intervening positional values are intercalated. The rate of segment formation is high when there is a wide gap in positional values between pygidium and adjoining budding zone and the posteriormost segment. As this gap narrows, the growth rate slows down. During caudal regeneration, first of all a new pygidium with an adjacent proliferation zone is formed and the original positional value of the posteriormost part of the body is reestablished. Segment regeneration follows the same rules as segment growth. The results presented here also demonstrate that the VNC plays an important role, not only in segment proliferation, but also in signalling positional information to the newly formed segments. 相似文献