35 resultados para Venation


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A new genus of philopotine Acroceridae in Baltic amber is described from both sexes. Archaeterphis hennigi gen. et sp. nov. is easily diagnosed from all other acrocerid genera by the deeply emarginate hind margin of the eye, short mouthparts, reduced wing venation, modified hind femora, and the large postpronotal lobes being proximate but not touching. The new genus is closely related to the extant genus Africaterphis Schlinger from southern Africa, which accords with a common biogeographic pattern in insects.

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Experiments are performed to determine the mass and stiffness variations along the wing of the blowfly Calliphora. The results are obtained for a pairs of wings of 10 male flies and fresh wings are used. The wing is divided into nine locations along the span and seven locations along the chord based on venation patterns. The length and mass of the sections is measured and the mass per unit length is calculated. The bending stiffness measurements are taken at three locations, basal (near root), medial and distal (near tip) of the fly wing. Torsional stiffness measurements are also made and the elastic axis of the wing is approximately located. The experimental data is then used for structural modeling of the wing as a stepped cantilever beam with nine spanwise sections of varying mass per unit lengths, flexural rigidity (EI) and torsional rigidity (GJ) values. Inertial values of nine sections are found to approximately vary according to an exponentially decreasing law over the nine sections from root to tip and it is used to calculate an approximate value of Young's modulus of the wing biomaterial. Shear modulus is obtained assuming the wing biomaterial to be isotropic. Natural frequencies, both in bending and torsion, are obtained by solving the homogeneous part of the respective governing differential equations using the finite element method. The results provide a complete analysis of Calliphora wing structure and also provide guidelines for the biomimetic structural design of insect-scale flapping wings.

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Detailed investigations on the structural and mechanical properties of the forewing of the cicada were carried out. Measurement of the structures of the wings showed that the thickness of the membrane of each cell and the diameter of each vein were non-uniform in both the longitudinal and transverse directions, and their means were approximately 12.2 and 133.3 mum, respectively. However, the aspect ratios of the wings and the bodies were quite uniform and were approximately equal to 2.98 and 2.13, respectively. Based on the measured thickness, mass and area of the membranes of the cells, the mean density and the mean area density of the wing were approximately 2.3 g cm(-3) and 2.8 x 10(-3) g cm(-2), respectively. In addition, the diameters of the veins of the wings, including the diameters of the holes in the vein of the leading edge, were examined. The mechanical properties of the wing were investigated separately by nanoindentation and tensile testing. The results indicated that the mean Young's modulus, hardness and yield stress of the membranes of the wings were approximately 3.7 Gpa, 0.2 Gpa and 29 Mpa, respectively, and the mean Young's modulus and strength of the veins along the direction of the venation of wings were approximately 1.9 Gpa and 52 Mpa, respectively. Finally, the relevant results were briefly analyzed and discussed, providing a guideline to the biomimetic design of the aerofoil materials of micro air vehicles.

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Machaerium é um dos maiores gêneros arbóreos tropicais de leguminosas, com cerca de 130 espécies com distribuição predominantemente neotropical e centro de diversidade no Brasil, onde ocorrem cerca de 80 espécies. O gênero ocorre em todos os domínios fitogeográficos do país, porém a Mata Atlântica e a Floresta Amazônica possuem os maiores índices de riqueza e endemismo. As espécies do gênero estão classificadas em cinco seções infragenéricas, que se baseiam principalmente na forma e venação dos folíolos e na presença de estípulas espinescentes. Entretanto, esta classificação tem sido questionada por alguns autores, principalmente quando comparada com análises filogenéticas. Dessa forma, surge a necessidade de buscar outros caracteres que auxiliem na delimitação das espécies e que permitam uma reavaliação na classificação nfragenéricas, além de conhecer o potencial para estudos dendrocronológicos das espécies em um bioma tão rico e ameaçado como a Mata Atlântica. O presente trabalho visou estudar a anatomia do lenho de onze espécies arbóreas de Machaerium a fim de verificar a consistência das seções infragenéricas, fornecer caracteres diagnósticos para a delimitação das espécies e caracterizar as pontoações intervasculares ornamentadas, para verificar seu potencial diagnóstico no gênero em questão. Além disso, analisar a periodicidade de crescimento e a influência dos fatores climáticos no crescimento de Machaerium incorruptibile, espécie endêmica da Mata Atlântica. As amostras foram coletadas através de método não destrutivo e processadas seguindo os métodos usuais para anatomia do lenho, microscopia eletrônica de varredura e dendrocronologia. As espécies apresentaram as características anatômicas descritas para a família Leguminosae e para a subfamília Papilionoideae. A presença de faixas de parênquima não lignificado, fibras de paredes delgadas e raios irregularmente estratificados foram importantes na separação de Machaerium hirtum das outras dez espécies. As dez espécies restantes foram separadas entre si pelos dados quantitativos do lenho, principalmente diâmetro e frequência de vasos, e também pelos caracteres morfológicos das pontoações ornamentadas, como a projeção ou não das ornamentações na abertura da pontoação. A anatomia da madeira não correspondeu as seções infragenéricas tradicionalmente tratadas para o gênero. Para a dendrocronologia os dados foram analisados com uso do software ARSTAN e foi construída uma cronologia para M. incorruptibile. As cronologias foram analisadas juntamente com os dados de precipitação e temperatura, onde observou-se uma correlação significativa com a temperatura. A largura dos anéis de crescimento foi correlacionada positivamente com a temperatura média da primavera, época em que a temperatura se encontra mais amena e, negativamente com a temperatura média do verão, onde as temperaturas são mais altas. Também houve correlação negativa entre os eventos mais severos de El Niño e a largura dos anéis de crescimento, demonstrando o efeito deste fenômeno no crescimento da população arbórea, como encontrado em outras espécies tropicais.

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上新世时期是地球环境发展变化过程中由温暖的中新世向冰期-间冰期交替出现的更新世的过渡时期,研究上新世的气候有助于研究现代全球气候变化趋势。我国上新世植物群研究不多,尤其缺乏早上新世植物群的研究。在研究化石植物群的过程中,叶角质层的信息通常被忽视。迄今,我国古气候的定量研究主要集中在山东山旺和云南地区,研究的主要是中新世和晚上新世的古气候,早上新世气候的定量研究国内外都未见报道。 本论文以采自浙江中部嵊州地区硅藻土中的植物叶和果实为材料,通过光学显微镜、荧光显微镜和扫描电镜观察,对提取的化石叶角质层和叶结构进行研究,对比研究现代相关类群植物的叶片,确定了化石植物类群计15科24属(或亚科)34种。同时参照现代植物分布,恢复了早上新世嵊州地区古植被情况,进一步运用共存分析(Co-existence Approch)定量重建了当时的古气候,得到古年均温、古年较差和古年降水量等7个参数。 研究表明,叶结构和叶角质层可以应用于化石植物类群的鉴定。光学显微镜和荧光显微镜下可以获得的信息有:气孔、表皮细胞形状及大小、表皮细胞垂周壁、分泌结构、表皮毛或毛基等。扫描电镜观察的是叶表皮细胞表面的情况,如细胞外壁是否被蜡质以及蜡质的交结情况,气孔外壁是否增厚呈环等。 经化石植物类群鉴定,早上新世(约4Ma)嵊州地区植被属亚热带常绿阔叶林。推测:该地区当时存在一个较大的湖泊,湖泊边缘水中生长有菱角,湖泊周边可能有海拔超过1400m的山地。 常绿阔叶林主要成分是壳斗科植物,其中青冈属植物可能是建群植物。自低海拔到高海拔地区都有分布的是:栎属、栗属、桤木属植物,青杨梅。低海拔地区(<600m)分布的植物有:海南锥,樟。中低海拔地区(300-1000m)分布着:柯属、黄杨属植物,水青冈,海南油丹,江南油杉,福建柏。中高海拔地区(>700m)分布有:高山栎、黄肉楠属植物,米心水青冈,榉树,建始槭,天台鹅耳枥和昌化鹅耳枥。除了上述类群,林中还散布着鼠李属、杜鹃花属和冬青属的植物,豆科崖豆藤属植物则缠绕一些较大乔木生长。另外,在一些土壤、有机质易堆积的洼地生长有竹林,山地贫瘠的地方生长着柏属植物。 嵊州早上新世化石植物群反映的植被同浙江地区现代植被相似。第三纪浙江地区从针叶林或阔叶树为主的针-阔叶混交林过渡到常绿-落叶阔叶林,再发展为常绿阔叶林。 依据23个植物类群分析获得7个古气候参数:年均温17.7-21.4°C,最热月均温22.2-27°C,最冷月均温8.4-13.4°C,年较差12.1-15.3°C,年降水量1136-1869.9mm,最大月降水量211.8-283.3mm,最小月降水量20.3-36.8mm。 对比现代嵊州地区气候参数,早上新世嵊州地区年降水量略高于现代,年均温比现代高1.3-5°C,年较差为12.1-15.3°C。早上新世期嵊州地区四季气温比现代平稳。

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钻地风属(Schizophragma Siebold & Zucc.)和冠盖藤属(Pileostegia Hook. f. & Thomson)隶属于虎耳草科绣球花亚科绣球花族植物,分布于东亚。本论文对钻地风属和冠盖藤属进行了全面的分类学研究:重点分析了钻地风属和冠盖藤属各形态性状的变异式样,确定了二属的性状变异范围;在光学显微镜下,对钻地风属中6种5变种和冠盖藤属中2种共130份材料的叶表皮特征进行了深入、全面的观察和研究;并对二属的叶脉序特征进行了研究。结果显示,苞片存在与否、不育花存在与否、花瓣顶端是否联合、蒴果和种子的形状、叶片质地、生长习性、表皮细胞垂周壁加厚与否、气孔器分布、类型、气孔大小、保卫细胞轮廓、外拱盖是否双层、二级脉、三级脉、高级脉及网眼等特征在属的水平上具有重要的分类学意义,这些性状特征支持将钻地风属和冠盖藤属作为两个独立的属处理。根据形态性状及叶脉序特征推测,冠盖藤属较原始,钻地风属较进化。在钻地风属中,叶片毛被的有无及类型、叶片形状和叶缘的形状等特征可作为可靠的分种依据;叶表皮特征在种及种下等级具有重要的分类学意义;叶脉序多呈现环节曲行羽状脉式样,二级脉具分枝,在种间存在细微差别。根据形态性状及叶脉序特征推测,厚叶钻地风S. crassum Hand.-Mazz.和白背钻地风S. hypoglaucum Rehder可能为钻地风属中较原始的类群,秦榛钻地风S. corylifolium Chun和绣球钻地风S. hydrangeoides Siebold & Zucc.可能较进化。在冠盖藤属中,叶片毛被的有无及类型、叶片形状等特征可作为可靠的分种依据;该属中叶表皮特征相似,2个种间叶表皮特征无差异;叶脉序多呈现环节曲行羽状脉式样,二级脉无分枝,在种间差异极小。 作者在研究了近2000份腊叶标本的基础上,结合叶表皮特征和叶脉序特征,认为钻地风属和冠盖藤属为两个独立的属。首次对钻地风属和冠盖藤属进行了世界性的分类学修订,确认钻地风属含7个种、5个变种,冠盖藤属含2个种。对钻地风属中的5个名称和冠盖藤属中的2个名称进行了归并;为钻地风属中的1个名称和冠盖藤属中的2个名称指定了后选模式;发现被命名为维西钻地风S. crassum Hand.-Mazz. var. hsitaoianum (Chun) C. F. Wei的类群其正确名称为S. crassum Hand.-Mazz. var. ellipticum J. Anthony;恢复了变种小粉绿钻地风S. integrifolium Oliv. var. minus Rehder;重新界定了白背钻地风和小粉绿钻地风的变异范围,澄清了中国文献中记载的粉绿钻地风S. integrifolium Oliv. var. glaucescens Rehder长期存在的名实混乱问题。本论文对各个分类群进行了详细的形态描述,给出了分种检索表,并附分布资料及地理分布图。

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Immunohistochemistry (IHC) is an essential tool in diagnostic surgical pathology, allowing analysis of protein subcellular localization The use of IHC by different laboratories has lead to inconsistencies in published literature for several antibodies, due to either interpretative (inter-observer venation) or technical reasons These disparities have major implications in both clinical and research settings In this study, we report our experience conducting an IHC optimization of antibodies against five proteins previously identified by proteomic analysis to be breast cancer biomarkers, namely 6PGL (PGLS), CAZ2 (CAPZA2), PA2G4 (EBP1) PSD2 and TKT Large variations in the immunolocalizations and intensities were observed when manipulating the antigen retrieval method and primary antibody incubation concentration However, the use of an independent molecular analysis method provided a clear indication in choosing the appropriate biologically and functionally relevant

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The Upper Jurassic-Lower Cretaceous dragonfly family Tarsophlebiidae is revised. The type species of the type genus Tarsophlebia Hagen, 1866, T eximia (Hagen, 1862) from the Upper Jurassic Solnhofen Limestones, is redescribed, including important new information on its head, legs, wings, anal appendages and male secondary genital apparatus. The type specimen of Tarsophlebiopsis mayi Tillyard, 1923 is regarded as an aberrant or unusually preserved Tarsophlebia eximia. One new species of Tarsophlebia and three new species of Turanophlebia are described, i.e. Tarsophlebia minor n. sp., Turanophlebia anglicana n. sp., T mongolica n. sp., and T. vitimensis n. sp. A new combination is proposed for Turanophlebia neckini (Martynov, 1927) n. comb. The phylogenetic relationships of the Mesozoic Tarsophlebiidae are discussed on the basis of new body and wing venation characters. The present analysis supports a rather derived position for the Tarsophlebiidae, as sister group of the the Epiproctophora rather than of (Zygoptera + Epiproctophora). Also, through the present discussion, the Oligo-Miocene family Sieblosiidae seems to be more closely related to the Epiproctophora than to the Zygoptera. But the present study and previous analyses suffer of the lack of informations concerning the more inclusive groups of Odonatoptera, viz. Protozygoptera, Triadophlebiomorpha, Protanisoptera, etc. The significance of the tarsophlebiid secondary male genital apparatus for the reconstruction of the evolution of odonate copulation is discussed.

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A flavonoid survey was carried out on 45 taxa from the genera Shorea, Hopea, Parashorea, Neobalanocarpus, and Dryobalanops of the tribe Shoreae in the Dipterocarpaceae. The study showed significant chemotaxonomic differences in leaf flavonoid aglycone patterns and the presence of tannins in these taxa. The flavonoid patterns are useful in the delimitation of some taxa. For example, the genus Parashorea is distinguished by the universal presence of kaempferol 3-methyl ether, and the monotypic genus Neobalanocarpus is unique in not producing ellagic and gallo tannins. The presence of chalcones and flavone C-glycosides supports the separation of the genus Hopea into two sections, section Dryobalanoides and section Hopea in Ashton's classification, which is based on the type of venation. The flavonoid distributions in this study show that they can be very useful for differentiating between the Balau group in the genus Shorea, and some scaly barked Hopea species, particularly H. helferi (lintah bukit), H. nutans (giam), and H. ferrea (malut). (C) 2008 The Linnean Society of London.

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Borassus akeassii Bayton, Ouedraogo & Guinko sp. nov. (Arecaceae) is described as a new species from western Burkina Faso in West Africa. It has been confused with the widely distributed African species B. aethiopum and more recently with the Asian B. flabellifer. However, it is distinguished by its glaucous, green leaves with weakly armed petioles and a characteristic pattern of lamina venation. The fruits have a pointed apex and are greenish when ripe, and the flowers of the pistillate inflorescence are arranged in three spirals. The pollen has a reticulate tectum and distinctive ornamentation. The distribution of B. akeassii is discussed and the status of the varieties of Borassus aethiopum (var. bagamojensis and var. senegalensis) is examined. (c) 2006 The Linnean Society of London.

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A flavonoid survey was carried out on 45 taxa from the genera Shorea, Hopea, Parashorea, Neobalanocarpus, and Dryobalanops of the tribe Shoreae in the Dipterocarpaceae. The study showed significant chemotaxonomic differences in leaf flavonoid aglycone patterns and the presence of tannins in these taxa. The flavonoid patterns are useful in the delimitation of some taxa. For example, the genus Parashorea is distinguished by the universal presence of kaempferol 3-methyl ether, and the monotypic genus Neobalanocarpus is unique in not producing ellagic and gallo tannins. The presence of chalcones and flavone C-glycosides supports the separation of the genus Hopea into two sections, section Dryobalanoides and section Hopea in Ashton's classification, which is based on the type of venation. The flavonoid distributions in this study show that they can be very useful for differentiating between the Balau group in the genus Shorea, and some scaly barked Hopea species, particularly H. helferi (lintah bukit), H. nutans (giam), and H. ferrea (malut). (C) 2008 The Linnean Society of London.

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Previous anatomical studies have been restricted to the foliar aspects of Pilocarpus. However, no anatomical studies analyzing the foliar aspects of Pilocarpus in relation to related genera have been carried out. Therefore, the aim of this study was to identify characters for future taxonomic and phylogenetic studies in Rutaceae, particularly in Pilocarpus, and to discuss the characteristics associated with the simple or compound leaf condition for the group. The petiole and the leaf blade of 14 neotropical Rutaceae species were analyzed, and the following characteristics were observed in all leaves studied: stomata on both surfaces; secretory cavities, including mesophyll type; camptodromous-brochidodromous venation pattern; and free vascular cylinder in the basal region of the petiole. Additional promising characters were identified for future taxonomic and phylogenetic studies in the Rutaceae family, especially for the Pilocarpus genera.

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We see today many efforts to quantify biodiversity in different biomes. It is very important then to develop and to apply other methodologies that allow us to assess biodiversity. Here we present an example of application of three tools with this goal. We analyzed two populations of Plebeia remota from two distinct biomes that already showed several differences in morphology and behavior. Based on these differences, it has been suggested that the populations of Cunha and Prudentopolis do not represent a single species. In order to verify the existence or absence of gene flow between these two groups, we characterized the patterns of mtDNA through RFLP, the patterns of wing venation through geometric morphometry, and the cuticular hydrocarbons through gas chromatography-mass spectrometry. We used bees collected in these two locations and also from colonies which have being kept for around 9 years at Sao Paulo University. We found six different haplotypes in these specimens, of which three of them occurred exclusively in the population of Cunha and three only in the Prudentopolis population. The fact that the populations do not share haplotypes suggests no maternal gene flow between them. The two populations were differentiated by the pattern of the wing veins. They also had different mixtures of cuticle hydrocarbons. Furthermore it was shown that the colonies kept at the university did not hybridize. These two groups may constitute different species. We also show here the importance of using other methodologies than traditional taxonomy to assess and understand biodiversity, especially in bees.