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11.
12.
Sadaf Habib Viet-Cuong Dang Stefanie M. Ickert-Bond Jun Wen Zhi-Duan Chen Li-Min Lu 《植物分类学报:英文版》2018,56(4):360-373
Tetrastigma (Miq.) Planch. (Vitaceae) is a genus with ca. 100 species showing great morphological diversity. Previous molecular phylogenetic studies suggested that traditional classification systems are not consistent with the molecular phylogeny, and Tetrastigma is undergoing further systematic investigation. We traced the evolutionary trends of 20 morphological characters within a robust phylogenetic framework. Our results revealed that many morphological characters show either multiple transitions or few state changes, however, some characters show distinct variation. The two subgenera in Tetrastigma (subgen. Tetrastigma and subgen. Palmicirrata) based on unbranched/bifurcate versus digitately branched tendrils are not supported because subgen. Tetrastigma is paraphyletic. However, the unbranched versus bifurcate/digitately branched tendril is of taxonomic utility to characterize some of the major clades. Inflorescences in Tetrastigma appear axillary, but are leaf‐opposed on a compressed axillary shoot. We found most of the species in Tetrastigma retained the ancestral compound dichasial inflorescence, except those of clade IV that have derived pseudo‐umbellate inflorescences. Other characters including habit, leaf organization, and berry shape provide additional morphological support for the major clades. Our morphological analysis and recent molecular study suggest each of the five major clades within Tetrastigma be treated as distinct taxonomic sections (five sections in the genus). 相似文献
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Systematic assessment of the Atelostomata (Spatangoida and Holasteroida; irregular echinoids) based on spine microstructure 下载免费PDF全文
Spines of irregular echinoids occur in very high abundance in each specimen, and display distinct architecture as a result of the specialized functions of the spines; however, studies on spine microstructure in atelostomate echinoids have rarely been carried out. Accordingly, little is known about their specific morphology. This work aims to elaborate differences in the spine morphology of selected Atelostomata (Spatangoida and Holasteroida) in detail, and to discuss spine microstructure for its potential systematic value. Based on 82 atelostomate species (56 spatangoids and 26 holasteroids), we show that the perforation pattern in the internal cylinder of the spine (helicoidal versus horizontal pattern) provides a safe distinction between the Spatangoida and Holasteroida. According to this character we discuss the geological history of atelostomate echinoids, in particular their migration into the deep sea, based on well‐preserved records of fossil spines. © 2015 The Linnean Society of London 相似文献
15.
W. Ellis Penning Marit Mjelde Bernard Dudley Seppo Hellsten Jenica Hanganu Agnieszka Kolada Marcel van den Berg Sandra Poikane Geoff Phillips Nigel Willby Frauke Ecke 《Aquatic Ecology》2008,42(2):237-251
Aquatic macrophytes are one of the biological quality elements in the Water Framework Directive (WFD) for which status assessments
must be defined. We tested two methods to classify macrophyte species and their response to eutrophication pressure: one based
on percentiles of occurrence along a phosphorous gradient and another based on trophic ranking of species using Canonical
Correspondence Analyses in the ranking procedure. The methods were tested at Europe-wide, regional and national scale as well
as by alkalinity category, using 1,147 lakes from 12 European states. The grouping of species as sensitive, tolerant or indifferent
to eutrophication was evaluated for some taxa, such as the sensitive Chara spp. and the large isoetids, by analysing the (non-linear) response curve along a phosphorous gradient. These thresholds
revealed in these response curves can be used to set boundaries among different ecological status classes. In total 48 taxa
out of 114 taxa were classified identically regardless of dataset or classification method. These taxa can be considered the
most consistent and reliable indicators of sensitivity or tolerance to eutrophication at European scale. Although the general
response of well known indicator species seems to hold, there are many species that were evaluated differently according to
the database selection and classification methods. This hampers a Europe-wide comparison of classified species lists as used
for the status assessment within the WFD implementation process. 相似文献
16.
Walking back the cat: Unsupervised classification as an aid in “remote” fossil prospecting 下载免费PDF全文
Glenn C. Conroy 《Evolutionary anthropology》2014,23(5):172-176
Counterintelligence analysts use a technique called “walking back the cat'' to reveal “moles” or others passing on disinformation in which they compare what they now know as fact against what their agents or informers had told them to expect about certain persons or events. 1 Thus, “walking back the cat” is a perfect metaphor for working backwards; that is, retracing the complex development of an event and examining the “run up” to it in order to gain useful insights about how that event unfolded. Perhaps paleoanthropology can profit from such an approach. 相似文献
17.
Juhani Kaakinen Toivo Kuokkanen Janne Pesonen Ilkka Välimäki 《Soil & Sediment Contamination》2014,23(4):437-451
The mining industry is a very rapidly increasing production sector in Finland. Many new mines have been opened recently and others are in the planning phase. Mining legislation has been recently revised and compilation of an ID-directive (Industrial Emission Directive, 2010) required to implement environmental law revision is in progress. The aim of this study was to compare different digestion methods recommended by the Finnish Environmental Administration for threshold and guideline value determinations in the Finnish PIMA Decree (214/2007) and Government Decree (591/2006) concerning recovery of certain wastes in earth construction. Altogether six methods were tested, of which five were microwave-assisted acid digestion methods: ISO 11466, EPA Method 3051A (aqua region), EPA Method 3051A (HNO3), EPA Method 3051A (HNO3/HCl), and SFS-EN 13656, while one was a fusion method with lithium tetraborate (ASTM C 1391 - 95). The results showed that concentrations of heavy metals (As, Cd, Co, Cu, Ni, Pb, Sb, V, and Zn) can be determined reproducibly with standard methods, but the chemical method used can have a significant impact on the results. This conclusion is very important, because the measured heavy metal values can affect the classification and processing of waste materials, and thereby can significantly impact the cost of treatment. 相似文献
18.
Eduardo Massad Annelies Wilder-Smith Raphael Ximenes Marcos Amaku Luis Fernandez Lopez Francisco Antonio Bezerra Coutinho Giovanini Evelim Coelho Jarbas Barbosa da Silva Jr Claudio José Struchiner Marcelo Nascimento Burattini 《Memórias do Instituto Oswaldo Cruz》2014,109(3):394-397
Brazil will host the FIFA World Cup™, the biggest single-event competition in the
world, from June 12-July 13 2014 in 12 cities. This event will draw an estimated
600,000 international visitors. Brazil is endemic for dengue. Hence, attendees of the
2014 event are theoretically at risk for dengue. We calculated the risk of dengue
acquisition to non-immune international travellers to Brazil, depending on the
football match schedules, considering locations and dates of such matches for June
and July 2014. We estimated the average per-capita risk and expected
number of dengue cases for each host-city and each game schedule chosen based on
reported dengue cases to the Brazilian Ministry of Health for the period between
2010-2013. On the average, the expected number of cases among the 600,000 foreigner
tourists during the World Cup is 33, varying from 3-59. Such risk estimates will not
only benefit individual travellers for adequate pre-travel preparations, but also
provide valuable information for public health professionals and policy makers
worldwide. Furthermore, estimates of dengue cases in international travellers during
the World Cup can help to anticipate the theoretical risk for exportation of dengue
into currently non-infected areas. 相似文献
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20.
A novel landscape classification system was proposed in this study based on landscape ecological theory and the differentiation in climate, topography, soil, vegetation and land use mode. Five basic units (zone, tract, province, region and type) and two assistant units (sub and group) were used in this system. The tropical forest landscape in Hainan Island was regarded as a landscape province, belonging to global tropical forest landscape zone, Asiatic (oriental) tropical forest landscape tract and Chinese tropical forest landscape subtract. Based on the grade system of region, sub-region, type-group and type, this landscape province (Hainan Island) is divided into 6 landscape regions (east moist forest landscape, west semi-arid forest landscape, central-south mountainous forest landscape, tropical evergreen needle-leaved forest landscape, tropical bamboo landscape and tropical plantation landscape), 11 tropical forest landscape sub-regions represented by tropical lowland valley rain forest landscape, 26 tropical forest landscape-type groups represented by tropical lowland valley Dipterocarpaceae forest landscape, and 54 forest landscape types (FLT) represented by lowland valley Vatica mangachapoi forest. Generally, this classification system represents the landscape diversity of the tropical forest in Hainan Island. Further studies are needed to better understand the landscape diversity of Hainan Island. 相似文献