971 resultados para Pachycondyla striata nest


Relevância:

10.00% 10.00%

Publicador:

Resumo:

分别从喂食三株原始产毒铜绿微囊藻Microcystis aeruginosa(AC、DS和PCC 7820)的金藻Poterioochromonassp.培养物中获得三株藻,以Nest PCR方法(引物对CC/CG和CH/CI)确定此三株藻均为微囊藻属藻株。HPLC测试结果显示这三株藻均不产生微囊藻毒素。显示Poterioochromonassp.具有将产毒微囊藻转化为无毒微囊藻的能力。比较产毒原始株与无毒变异株的生理特性发现,变异株的类胡萝卜素/叶绿素比值高于原始株;而光反应曲线结果表明,变异株的PSⅡ

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This paper presents a generalized vector control system for a generic brushless doubly fed (induction) machine (BDFM) with nested-loop type rotor. The generic BDFM consists of p1/p2 pole-pair stator windings and a nested-loop rotor with N number of loops per nest. The vector control system is derived based on the basic BDFM equation in the synchronous mode accompanied with an appropriate synchronization approach to the grid. An analysis is performed for the vector control system using the generic BDFM vector model. The analysis proves the efficacy of the proposed approach in BDFM electromagnetic torque and rotor flux control. In fact, in the proposed vector control system, the BDFM torque can be controlled very effectively promising a high-performance BDFM shaft speed control system. A closed-loop shaft speed control system is composed based on the presented vector control system whose performance is examined both in simulations and experiments. The results confirm the high performance of the proposed approach in BDFM shaft speed control as well as a very close agreement between the simulations and experiments. Tests are performed on a 180-frame prototype BDFM. © 2012 IEEE.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

<正> 作者在进行四川、云南硅藻分类研究中,发现了星肋小环藻的一新变种,定名为星肋小环藻线纹变种(Cyclotella asterocoaata var.striata),为编写《中国硅藻志》提供资料。星肋小环藻线纹变种(新变种)(图1)。Cyclotella asterocostata var. striata, var. nov. Differt a typo valvis in margine areae centralis striis puncticulosis (22—24 in 10μm)r

Relevância:

10.00% 10.00%

Publicador:

Resumo:

本研究以凤鹛属(Yuhina)鸟类为研究对象,分别使用分子生物学性状和形 态学性状来重建凤鹛属种间的系统发育关系,为东南亚地区鹛类的起源与进化研 究提出新的见解。分子生物学研究的内群不仅包括了凤鹛属(11 种中的10 种), 而且还包括了菲律宾特有穗鹛属(Stachyris)和绣眼鸟属(Zosterops)等近缘种。 通过测定线粒体上两个蛋白编码基因Cyt b、ND3 的全长序列和两个RNA 编码 基因 12S, 16S 的部分序列,得到长度为2379bp 的联合序列,使用最大简约法、 最大似然法和贝叶斯法进行系统发育分析的结果表明,菲律宾岛特有的穗鹛(金 冠穗鹛S. dennistouni、纹穗鹛S. striata、怀氏穗鹛S. whiteheadi)与绣眼鸟属(暗 绿绣眼Z. japonicus、红胁绣眼Z. erythropleurus、灰腹绣眼Z. palpebrosus)聚为 一支,位于凤鹛属支系内部。通过凤鹛、菲律宾穗鹛、绣眼鸟三个类群羽冠性状 演化趋势的分析,发现羽冠性状在菲律宾特有穗鹛和绣眼鸟支系中发生丢失。与 前人的研究结果相比,新发现纹喉凤鹛Y. gularis 与棕肛凤鹛Y. occipitalis 是姐妹 群,黄颈凤鹛Y. flavicollis 和白项凤鹛Y. bakeri 是姐妹群,这两个姐妹群又聚为 一大支的关系。 在分类问题上,暗绿绣眼、红胁绣眼和灰腹绣眼在本研究中与鹛类表现出近 缘关系,与前人使用绣眼鸟属其它物种进行的相关研究显示出高度一致性,说明 绣眼鸟属的系统学地位存在很大疑问,应该扩大取样进行深入研究。栗冠凤鹛 Y. everetti 与栗耳凤鹛Y. castaniceps 聚为姐妹群的关系,但是二者之间较小的遗 传距离和形态学差别显示二者之间应该为亚种关系,而不是种级关系。依据栗耳 凤鹛特有的尾羽形态提出的Staphiada 属没有得到本分子生物学研究结果的支持 (Harrison, 1986a, b)。在白腹凤鹛Y. zantholeuca 不属于凤鹛属支系这一结果的 提示下,发现白腹凤鹛独有的形态学特征,例如羽冠由冠羽形成、鼻孔半裸露、 飞羽外翈没有异色羽缘,这些独有的特征与其特殊的系统学地位相对应。因此, 我们支持前人提出的将白腹凤鹛从凤鹛属中分出去,单独成Erpornis 属的建议 (Cibois et al., 2002)。 在历史生物地理学方面,根据菲律宾特有穗鹛和绣眼鸟的近缘关系,认为菲 律宾特有穗鹛的祖先具有与现在绣眼鸟一样的跨海迁移的能力,在中新世末期(5.74Mya)由喜马拉雅地区或印度支那起源地经大巽他地区扩散到菲律宾岛屿 上,经过长期独立进化后,形成现在高度特有的穗鹛支系。更新世冰期时,大巽 他地区海平面下降,使栗冠凤鹛得以扩散至婆罗州(1.66Mya)。在上新世初期台 湾岛成陆后,由于台湾岛与中国大陆相连,褐头凤鹛Y. brunneiceps 的祖先扩散 至台湾岛屿上(5.05Mya)。高黎贡山为第四纪冰期时凤鹛属鸟类的避难场所,因 此形成了现在凤鹛属鸟类在高黎贡山地区密集分布的格局。喜马拉雅山和青藏高 原的隆起导致青藏高原上植被带的变化和喜马拉雅山南麓在第四纪冰期中避难 所的作用,是纹喉凤鹛、棕肛凤鹛、黄颈凤鹛、白项凤鹛等种类现今在喜马拉雅 山南麓密集分布的可能原因。 在凤鹛属分子系统学的研究基础上,从形态学角度探讨凤鹛属除白领凤鹛外 其它物种之间的系统发育关系。使用最先分化出来的白领凤鹛为外群以外群比较 法进行51 个形态学特征的性状极化,使用最大简约法分析后,结果不仅支持一 些分子系统学揭示的物种之间的亲缘关系,例如,栗耳凤鹛与栗冠凤鹛姐妹群的 关系,黑颏凤鹛和褐头凤鹛姐妹群的关系,三种绣眼鸟聚为一支,再与怀氏穗鹛 聚为一个大支;而且发现了新的系统关系,黄颈凤鹛与缅甸凤鹛Y. humilis 是姐 妹群,具有浅色下体的凤鹛属物种具有较近的系统关系。分子数据和形态数据对 凤鹛属系统发育树中部节点解决能力的差异,说明凤鹛属物种之间分化间隔时间 很短。 通过综述近年来核基因在鸟类分子系统发育研究中的应用情况,建议未来研 究中增加核基因的内含子序列,例如肌球素基因内含子2( myoglobin intron Ⅱ) 或β纤维蛋白原基因内含子7(β-fibrinogen intron7, β-fibint 7)来解决本研究 中未确定的末端分枝分歧顺序。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

genetics, such as: population size, reproduction, mating system, growth, development,genetic structure and systematics status; The main results are presented below: The seasonal variation of the operational sexual ratio of this animal was found in the field and the ration always bias the female in the breeding season. Aiming at this character and considering the distance of time and space of both sexual habitat in breeding season, we census female population first by toe-clipping mark-recapture method, then estimated the population size with the definitive sexual ratio. Up to now, this species was found only at the Beilun district of the Ningbo City. The population size of the Ruiyan Temple Forest Park approximates to 369. The status of this population is extremely endangered, so besides protecting this population at the original locality, we also suggested to breed the salamander in fenced locality and to hatch embryos artificially, and send metamorphosed juveniles back to nature. We can transfer some individuals to other similar habitats or breed them under artificial conditions for saving this species from extinction. The early developmental stage of the Chinhai salamander is the same as its relative species, E. andersoni. Their balanceres are poorly developed and disappear very early. Temperature and moisture significantly influence the embryonic development of the Chinhai salamander. The embryonic stage is approx. 29 days under room temperature. The hatchling grows in a logarithmic curve. The larvae stage in water is approx. 58- 88 days. Many factors influence the nomal development, including two aspects of internal and external. Due to these factors, the effective protected measures were presented in detail. The breeding migration of E. chinhaiensis takes place at late March~late April every year. This salamander's hatching rate is high, but the rate of hatchling migrating into water is low. The average effectiveness of all the nest sites is 36.7%. The maternal self-conservation was contrary to the reproductive success of the egg-laying strategy. In the strategy of egg-laying behavior, the first factor selected by the female was its self-conservation, the second is embryonic survival rate, and the last is rate of hatchling survival rate. The oviposition selection is significant for the survival of the larvae. Based on the analysis of the evolutionary process of reproductive behaviors nad egg-laying site selections of all genera of the family Salamandridae, we deduced that perhaps Echinotriton is a transitional type in the evolutionary process from water to land. Due to its location in the adaptive stage in the terrestrial evolution, Echinotriton chinhaiensis's terrestrial nest may be one of important reason that causes this species to be endangered. The genetic deversity analysis shows that although the population size of the Chinhai salamander is quite small compared to other Chinese salamandrid species, the genetic diversity of this population is not reduce remarkably. We explain this phenomena with the polygamy mating system of this species. The result of 4 families' parenthood determinations shows that the parenhood determination can be taken without any paternal information. The "children" of every female include rich genetic information from at least two "fathers". It implies that female Chinhai salamander mates more than once with different males in a breeding season. The molecular evidence, the behavioral observation evidences and the sperm evidence in the female cloaca proved that this species has a polygamy mating system. The kin recognition in the mating of adult salamander was first discussed. The taxonomic status and phylogenetic relationships of 12 species representing 6 genera in the family Salamandridae were studied using DNA fingerprinting. The results showed that the DNA fingerprinting. The results showed that the DNA fingerprinting patterns demonstrated rich genetic diversity and species diversity, and also revealed the taxonomic status and phylogenetic relationshipes of higher taxa to a certain extent. The results are highly consistent with those obtained from the studies based on the morphology, ecology, cytology and molecular biology. The compreshensive analysis indicate that Tylototrition hainanensis and T. wenxianensis should be valid species; Echinotriton should be a valid genus;Tylotortriton is a natural cluster; Tylotortriton asperrimus should be put in Tylototrition rather than in Echinotriton, Hypselotriton and Allomestriton are synonyms of Cynops and Paramesotriton, respectively. There are three main groups in Chinese salamandride: Cynops, Paramesotriton and Pachytrition from the first group, the species of the Tylototriton from the second, and E. chinhaiensis composes the third.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

本研究是围绕昆虫的假死行为及建巢相关行为两个方面进行的。首先通过对昆虫假死行为的研究历史和现状的综述,作者提出了假死行为是一种特殊拟态的观点。对长壮蝎蝽Laccotrephes robustus Stål成虫在不同的活动空间下(水体内外)的假死行为以及控制假死行为的关键部位的研究结果表明:(1)水体外假死时长明显高于水体中;(2)蝎蝽在水体内外假死行为的差别是对不同捕食压力的适应,能够提高自身的适合度;(3) 头部不是蝎蝽假死发生所必需的,控制胸部各对足完成假死动作的神经节可能是不同的。胡蜂类昆虫的建巢行为直接关系到其蜂群的发展和存活。平唇原胡蜂Prevespa barthelemy (Buysson)隶属于胡蜂科,是一种社会性昆虫。为研究已建造蜂巢的相关生物学特征,对其越冬后蜂巢进行了解剖观察。结果表明:(1)蜂巢中部较大的巢脾为主要的繁殖区;(2)幼虫和工蜂所占比率最高,占全巢各虫态总数的70%左右;(3)巢中成熟个体,除蜂后外其余全部为雌性工蜂;(4)由于当地气候适宜,越冬期的低温虽使其活动能力下降,但不会引起大量死亡,该胡蜂可以在原巢址内越冬。胡蜂类昆虫雌蜂单母建群的过程可以视为是昆虫社群生活起源的短暂重现,对单母建群行为的研究有助于理解昆虫群居生活的发生和发展。通过对焰马蜂Polistis adustus Birgham单母建群过程的观察,结果表明:(1)第一批工蜂羽化前,雌蜂同时担任蜂王和工蜂的职责;(2)各虫态发育历期卵为5-7 d;幼虫13-15 d;蛹为24-28 d;(3) 单母建群时期是决定未来蜂群发展的重要阶段,也是对马蜂类天敌昆虫进行保护和利用的关键时期。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

6-Bromo-1-(3-bromo-4,5-dihydroxybenzyl)phenanthro[4,5-bcd]furan-2,3,5-triol (urceolatin, 1), a highly oxygenated bromophenol containing an unprecedented naturally occurring benzylphenanthro[4,5-bcd]furan unit, was isolated from the marine red alga Polysiphonia urceolata. Its structure was established on the basis of extensive spectroscopic analysis. Compound 1 displayed significant DPPH radical-scavenging activity with an IC50 value of 7.9 mu M, which is 10-fold more potent than that of the positive control, butylated hydroxytoluene.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

首次报道了条纹龙胆(Gentiana striata Maxim.) 的胚胎学特征, 研究结果用以讨论龙胆属狭蕊组(Gentiana Sect.Stenogyne) 的系统演化关系。主要研究结果如下: 花药四室; 药壁发育为双子叶型; 绒毡层细胞仅来源于初生壁细胞, 故绒毡层起源属单型起源, 细胞具单核,原位退化, 属腺质型绒毡层, 药隔处的绒毡层细胞经多次平周分裂形成2 层至多层的绒毡层细胞, 其余部位的绒毡层细胞仍为1 层细胞; 中层细胞1 层;在花药成熟时, 花药的表皮细胞和药室内壁均部分纤维状加厚且柱状伸长。小孢子母细胞减数分裂为同时型, 四分体的排列主要为四面体形;成熟花粉为32细胞型。子房为2心皮, 1室, 侧膜胎座。胚珠4列。薄珠心,单珠被, 珠心基部产生珠被原基, 进而形成珠被, 条纹龙胆仅有1 层珠被。珠被沿珠心向上生长并将珠心包围, 于胚珠顶部形成珠孔。胚珠在发育过程中, 整个胚珠的本体倒转, 而且珠柄继续生长并弯曲, 使珠孔与合点端的连线与珠柄垂直, 形成Hypertropous 胚珠。大孢子母细胞减数分裂形成的4 个大孢子呈直列式排列, 合点端的大孢子具功能。胚囊发育为蓼型。极核在受精前融合为次生核, 反足细胞3 个、多宿存。雄蕊先熟。珠孔受精。胚乳发育为核型。胚胎发育为茄型酸浆Ⅱ变型。通过比较龙胆属狭蕊组与龙胆属其它组和双蝴蝶属的胚胎学特征表明, 龙胆属狭蕊组在一些重要的胚胎学特征上与双蝴蝶属较相似, 而与龙胆属其它组存在较大差异, 故建议应将龙胆属狭蕊组从龙胆属中移出。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Dissertação de Mestrado apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Psicologia.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Dissertação de Mestrado apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Psicologia, especialização em Psicologia Clínica e da Saúde.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Over the last 30 years, western European Song Thrush populations have declined with the steepest decline recorded on British farmland. Changes in agricultural practices have been implicated in these population declines. Ireland is an agriculturally dominated landscape but changes in agriculture here have occurred on a relatively slower rate and scale. Little is known about the ecology of the Song Thrush in Ireland, even though it is not classified as a species of conservation concern here. Some decline is thought to have occurred but the current breeding population appears to be stable and widespread. In light of these facts, this study investigated various aspects of Song Thrush ecology in relation to the Irish landscape from 2001-2003. The breeding season extended from mid March to late June, where mean clutch size was 4.1 and number of fledglings was 3.7. There were very few third broods. Daily nest survival rates were calculated for egg stage 0.9362, incubation stage 0.9505 and nestling stage 0.6909. Most nest failures were due to avian predation at both egg and chick stages. Most nests were located 1.3 -2.4m from the ground at trees, bushes or hedgerow. Clutch size was significantly higher on farmland than garden & parkland and woodland, and the number of fledglings was significantly lower in nests in trees than hedgerow and bush sites. Daily nest fail rates were significantly higher at tree sites and partly concealed nests. Nesting areas had significantly denser vertical vegetation than non-nesting areas. Mercury and the organochlorine HEOD were the most common contaminants in Song Thrush eggs and livers. However concentrations and occurrence were low and of no apparent biological or ecological concern. The presence of breeding Song Thrushes was influenced by mixed surrounding farmland, the absence of grass surrounding farmland, ditches especially wet ones, tall dense vegetation and trimmed boundaries. Song Thrush winter densities were predicted by ditches, with wet or dry, low thin vegetation and untrimmed boundaries. Winter densities were almost double that of the breeding season, probably due to the arrival and passage of migrating Song Thrushes through the country, especially in November. Changes in Irish agriculture did not differ significantly in areas of Song Thrush breeding population stability and apparent decline during 1970 1990. Even though the current breeding population heavily uses farmland, woodland, human and scrub habitats are more preferred. Nevertheless no farmland habitat was avoided, highlighting a positive relationship between breeding Song Thrushes and Irish agriculture. This appears to be in contrast with findings between breeding Song Thrushes and British agriculture. Theses findings are compared with other studies and possible influences by agricultural intensification, climate, latitude and insular syndrome are discussed. Implications for conservation measures are considered, especially for areas of decline. Even though Song Thrushes are currently widespread and stable here, future environmental consequences of longer-term changes in Irish agriculture and perhaps climate change remain to be seen.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This thesis is based on studies of Formica lugubris from 1972-1975. While this species' range is diminishing in Ireland, the nests are quite common in the State plantations of South Tipperary. It is not certain that the species is indigenous. Above-ground activity occurs from late-February to the end of October; foraging begins in April. Two territorial "spring-battles" between neighbouring nests are described. Most active nests produced alatae of both sexes and flights were observed on successive June mornings above l7.5°C air temperature. Both polygyny and polycaly seem to be rare. Where the nests occur commonly, the recorded densities are similar to those reported from the continent. Most nests persisted at the same site since 1973. The nest-sites are described by recording an array of nest, soil, tree, vegetation and location variables at each site. Pinus sylvestris is the most important overhead tree. Nests seem to be the same age as their surrounding plantation and reach a maximum of c. 30 years. Nearest-neighbour analysis suggests the sites are overdispersed. Forager route-fidelity was studied and long-term absence from the route, anaesthetization and "removal" of an aphid tree had little effect on this fidelity. There were no identifiable groups of workers specifically honeydew or prey-carriers. Size-duty relationships of workers participating in adult transport are described. Foraging rhythms were studied on representative days: the numbers foraging were linearly related to temperature. Route-traffic passed randomly and an average foraging trip lasted c. four hours. Annual food intake to a nest with 25 000 foragers was estimated at approximately 75 kg honeydew and 2 million prey-items. Forager-numbers and colony-size were estimated using the capture-mark - recapture method: paint marking was used for the forager estimate and an interval radiophosphorus mark, detected by autoradiography, was used for the colony-size estimate. The aphids attended by lugubris and the nest myrmecophiles are recorded.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Plastic debris is now ubiquitous in the marine environment affecting a wide range of taxa, from microscopic zooplankton to large vertebrates. Its persistence and dispersal throughout marine ecosystems has meant that sensitivity toward the scale of threat is growing, particularly for species of conservation concern, such as marine turtles. Their use of a variety of habitats, migratory behaviour, and complex life histories leave them subject to a host of anthropogenic stressors, including exposure to marine plastic pollution. Here, we review the evidence for the effects of plastic debris on turtles and their habitats, highlight knowledge gaps, and make recommendations for future research. We found that, of the seven species, all are known to ingest or become entangled in marine debris. Ingestion can cause intestinal blockage and internal injury, dietary dilution, malnutrition, and increased buoyancy which in turn can result in poor health, reduced growth rates and reproductive output, or death. Entanglement in plastic debris (including ghost fishing gear) is known to cause lacerations, increased drag—which reduces the ability to forage effectively or escape threats—and may lead to drowning or death by starvation. In addition, plastic pollution may impact key turtle habitats. In particular, its presence on nesting beaches may alter nest properties by affecting temperature and sediment permeability. This could influence hatchling sex ratios and reproductive success, resulting in population level implications. Additionally, beach litter may entangle nesting females or emerging hatchlings. Lastly, as an omnipresent and widespread pollutant, plastic debris may cause wider ecosystem effects which result in loss of productivity and implications for trophic interactions. By compiling and presenting this evidence, we demonstrate that urgent action is required to better understand this issue and its effects on marine turtles, so that appropriate and effective mitigation policies can be developed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Dimensiosis des galbules et/ou teneur en prodelphinidine des aiguilles permettent trés généralement de déterminer les sous-espéces oxycedrus et macrocarpa, respectivement septentrionale-continentale et méridionale-insulaire, du Genévrier oxyeédre Juniperus oxycedrus L. Parcontre, la sous-espéce nord-africaine rufescens (en montagne) ne parah pas distinguable à ces titres de la sous-espéce type. Mais l’étude biochimique plus approfondie d’une (méta)population languedocienne montre l’existence d’un polymorphisme proanthocyanique indépendant de la taille des galbules. Les deux sous-espéces classiquement reconnues pourraient donc n’étre que les formes extremes, homozygotes pour le caractére chimique considéré, d’un méme génóme spécifique. Si les spécimens littoraux (Corse, Majorque, Maghreb) correspondent bien à la pleine expression (= prodelphinidine forte) de ce polymorphisme, certains échantillons «péri-littoraux» (Baléares et Languedoc) trahissent une introgression (actuelle ou ancienne) ayee appartion d’individus hétérozygotes, aux teneurs intermédiaires: des génes «macrocarpa» sont done bien presents au nord de la Méditerranée, méme si le phénoméne n’est pas morphologiquement décelable, et ne mérite pas d’étre formalisé en termes systématiques.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Lasioglossum malachurum, a bee species common across much of Europe, is obligately eusocial across its range but exhibits clear geographic variation in demography and social behaviour. This variation suggests that social interactions between queens and workers, opportunities for worker oviposition, and patterns of relatedness among nest mates may vary considerably, both within and among regions. In this study, we used three microsatellite loci with 12–18 alleles each to examine the sociogenetic structure of colonies from a population at Agios Nikolaos Monemvasias in southern Greece. These analyses reveal that the majority of colonies exhibit classical eusocial colony structure in which a single queen mated to a single male monopolizes oviposition. Nevertheless, we also detect low rates of multiqueen nest founding, occasional caste switching by worker-destined females, and worker oviposition of both gyne and male-producing eggs in the final brood. Previous evidence that the majority of workers show some ovarian development and a minority (17%) have at least one large oocyte contrasts with the observation that only 2–3% of gynes and males (the so-called reproductive brood) are produced by workers. An evaluation of the parameters of Hamilton's Rule suggests that queens benefit greatly from the help provided by workers but that workers achieve greater fitness by provisioning and laying their own eggs rather than by tending to the queen's eggs. This conflict of interest between the queen and her workers suggests that the discrepancy between potential and achieved worker oviposition is due to queen interference. Comparison of relatedness and maternity patterns in the Agios Nikolaos Monemvasias population with those from a northern population near Tübingen, Germany, points to a north–south cline of increasingly effective queen control of worker behaviour.