Jiang W.,East China Normal University |
Liu N.,East China Normal University |
Zhang G.,East China Normal University |
Li T.,Centers for Disease Control and Prevention |
And 2 more authors.
Parasitology Research | Year: 2012
There are three Echinococcus species, Echinococcus granulosus, E. multilocularis, and E. shiquicus, which are distributed on the vast area of pastureland on the eastern Tibetan plateau in China. Tibetan foxes (Vulpes ferrilata) have been determined to be the main wild definitive host of E. multilocularis and E. shiquicus, but little information is available on the prevalence of these two parasites in Tibetan foxes. Consequently, the coproprevalence of these parasites in foxes from the eastern Tibetan plateau was evaluated in this study. For each copro-DNA sample extracted from fox feces, a 133-bp segment of EgG1 Hae III was used to screen for infection with E. granulosus. Multiplex nested polymerase chain reaction (PCR) analysis was used to target an 874-bp segment of the mitochondrial COI gene to distinguish E. multilocularis and E. shiquicus. Among 184 fecal samples, 120 were from Tibetan foxes and six from red foxes (Vulpes vulpes). Of the fecal samples from Tibetan foxes, 74 (giving a copro-prevalence of 62 %) showed the presence of Echinococcus spp.: 23 (19 %) were found to contain E. multilocularis, 32 (27 %) E. shiquicus, and 19 (16 %) showed mixed infection with both E. multilocularis and E. shiquicus. Two fecal samples from red foxes were found to be infected with E. multilocularis. No fox feces were found to be infected with E. granulosus. Tests on zinc finger protein genes and a 105-bp fragment of the Sry gene found no significant difference in the prevalence of the two parasites between sexes. The efficiency of our multiplex nested PCR methods were compared with previous polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) methods and some problems associated with the copro-PCR were discussed. © Springer-Verlag 2012.
Xu J.,Shanghai University |
Li D.,Shanghai University |
Fang H.,Shanghai Science and Technology Museum
Lecture Notes in Electrical Engineering | Year: 2012
The original images were obtained from the uniaxial compression tests of limestone and transformed into the static and responding grayscale ones. The displacement field was computed using the particle image velocimetry technique. The strains were obtained from the displacements using the local least square method and investigated at different locations. It was found that the deformation changes steadily followed by a rapid increase as time passes and only a few of them had been developed into the visible cracks, although several deformation concentrations occurred in the specimen under the compression loads. The techniques presented herein provide valuable information in investigating the failure mechanism of the rock materials. © 2012 Springer-Verlag Berlin Heidelberg.
Xu J.,Shanghai University |
Feng X.,Shanghai University |
Xu X.,Shanghai Science and Technology Museum |
Chen B.,Shanghai Science and Technology Museum
Lecture Notes in Electrical Engineering | Year: 2012
The video images photographed in laboratory tests were used to investigate the fissure changes in granite. Frames were extracted out and investigated using the digital image processing. The intro-frame average technique was utilized to overcome the effects of sample trembles on the image processing. The locations of the micro compositions, especially those of new-generated fissures, were examined using fractional differential. The effects of the surrounding factors on the image properties were also examined. A criterion of image characteristic parameters for generating new fissures was furthermore proposed. The method proposed herein may be used as references in analyzing the physical mechanism of deformations and failures of rock materials or rock masses in rock regions. © 2012 Springer-Verlag Berlin Heidelberg.
Xu J.-M.,Shanghai University |
Xie Z.-L.,Shanghai University |
Jia H.-T.,Shanghai Science and Technology Museum
Yantu Lixue/Rock and Soil Mechanics | Year: 2010
The formation and development of geological disasters in rock area are dependant on the kinematic behaviors of rocks, especially of grains, fissures, and fillings in the rocks. In the conventional studies, rocks are generally treated as entireties and few concerns are concentrated on the individual meso-compositions in these rocks. Taking a limestone for example, macromechanical properties were obtained for the rock specimens of laboratory tests; and particle flow code in two-dimensions (PFC2D) was used for simulating the macromechanical properties of the rock material. In the simulation, the material was discretized as an assembly of rigid particles. The mesomechanical parameters, such as contact forces, contact modulus, normal contact strengths, and stiffness ratio, were obtained; and the mesostructural model was established for the limestone; connecting meso-level changes in particles with macromechanical properties. Because the individual compositions were taken as the direct objectives, reflecting the intrinsic features of rock materials or rock masses, the techniques presented herein may be of great significance in studying the constitutive law of fissured rocks, engineering properties of rock masses, and mechanism of geological disasters.
Gao B.,CAS Institute of Zoology |
Gao B.,University of Chinese Academy of Sciences |
Yu L.,Shanghai Science and Technology Museum |
Qu Y.,CAS Institute of Zoology |
And 8 more authors.
International Journal of Molecular Sciences | Year: 2011
Recent phylogeographical studies indicated that glacial oscillations played a key role on the phylogeographic pattern of extant species. As most studies have previously been carried out on heavily ice-covered regions, such as in European and North American regions, potential effects of climatic oscillations on species that are distributed on ice-free regions are less known. To address this, we investigated the phylogeographic pattern of an avian species endemic to South China, which was not glaciated during the Pleistocene glaciations. By using 2142 bp mitochondrial DNA, we identified 89 haplotypes defined by 39 polymorphic sites. A combination of high haplotype diversity (0.786-1.00) and low nucleotide diversity (0.00132-0.00252) was detected among geographic populations. Explicit genetic divergence was observed between S. s. semitorques and S. s. cinereicapillus but not detected among geographic populations of S. s. semitorques. Divergence time of the two subspecies was dated back to 87 Kyr which is congruent with the interglacial MIS 5. A weak phylogeographic structure due to strong gene flow among geographic populations was identified in this species, suggesting complex topography of South China has not formed barriers for this species. © 2011 by the authors; licensee MDPI, Basel, Switzerland.
Gao L.,CAS Xishuangbanna Tropical Botanical Garden |
Li B.,Fudan University |
Jin L.,Shanghai Science and Technology Museum
Applied Ecology and Environmental Research | Year: 2016
Increasing concentration of nutrients in water is regarded as one of the most important external factors responsible for the invasion of the common water hyacinth. In order to test whether nutrient availability limits the growth and spread of this species, we investigated the influence of water nitrogen (N) and phosphorus (P) concentrations on growth using both greenhouse and field experiments. We found that in the greenhouse experiment, only high P concentration (>1.25 mg l-1) can significantly increase numbers of ramets and leaves, and N concentration exceeding 62.5 mg l-1 can greatly increase water hyacinth biomass in a tank. In the field experiment, the clonal growth of water hyacinth was not correlated with N and P concentrations in water bodies where the range of N and P concentrations was narrow compared with their range in the greenhouse. This suggests that controlling water hyacinth through minimizing sewage discharging is impractical, the importance of the ability of water hyacinth to grow clonally should be considered. © 2016, ALÖKI Kft., Budapest, Hungary.
Wang B.,East China Normal University |
Wang X.,Shanghai Science and Technology Museum |
Wang T.,East China Normal University |
Ding Y.,East China Normal University
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2012
Urban woodlots are isolated patches with habitat features similar to 'habitat islands'. Spatial patterns between and within animal communities change with respect to habitat fragmentation, and this is especially the case for avian communities. The purpose of this paper was to test for nestedness within passeriformbird assemblages across urban woodlots of Shanghai, China and to inform conservation planning across this heavily populated city. From November 2008 to October 2009, we used line transect and point count methods to survey distribution patterns and species richness of passeriform birds across seven urban areas in the Minhang district of Shanghai. Areas surveyed included a neighborhood park, tourist park, sports park and water conservation forest, representing the main types of urban woodlots found in the area. Through surveys and satellite images we recorded park area, vegetation coverage, the distance from the center of the park to nearest water, and the extent of anthropogenic disturbance (distance from the center of habitat to arterial road). We used the Nestedness Temperature Calculator to examine whether bird communities in this area show signs of nestedness and what factors may be responsible for such a pattern. Results showed that the passeriform bird community followed a significant nested pattern influenced by habitat area, vegetation cover and water condition. However, nestedness was different from a real 'island' condition. Anthropogenic disturbance was also found to influence nestedness. Investigating the matrix system in which the urban woodlot bird communities are comprised showed that the temperature is 21. 78°C, compactedness is 41. 3%, and the number of species is between 14 to 38. Eleven kinds of bird exist across the seven focal urban areas, such as Motacilla alba and Parus major. However, some species as Dicrurusmacrocerus, Orioluschinensis are only found in a particular focal area. Habitat fragmentation contributes to the spread of birds. However, different urban woodlots have distinct habitat characters due to heterogeneity and human activities also interfere with the spread of birds and habitat choice. Vegetation also appears to influence the distribution of birds across urban woodlots. Birds tend to choose particular kinds of urban woodlots that include diverse species, have complex structure or are at a stage of senior evolution. These regions could provide stable food sources and concealed breeding grounds and habitats. Our findings suggest that more attention should be directed towards large habitats, those with a high level of vegetation cover and plant richness, and a reasonable structure of urban woodlot. From the point of nestedness stability, urban environments show instability following city development. Frequent change in urban woodlots influences the migration and spread of birds, and this is a fundamental difference from how 'habitat islands' function. Based on the application of 3S technologies to urban planning and ecological monitoring we can now utilize advanced technology such as remote sensing and GIS to monitor variation in urban woodlots and prevent the further habitat fragmentation. The extent of anthropogenic disturbance should be minimized when planning and constructing urban woodlots in major cities.
Mazak J.H.,Shanghai Science and Technology Museum
Journal of Zoology | Year: 2010
There is still no uncontroversial agreement on the geographical variation, subspecies taxonomy and phylogenetic relationships between major populations of the lion Panthera leo. This study examines the patterns of geographical variation and phylogenetics of lions based on an extensive morphometric analysis on 255 wild lion skulls. The results of multivariate analysis of craniometric data indicate that lion skulls vary considerably throughout their geographical range and that the variation is greater within populations than between them, a significant subdivision being found only between sub-Sahara Africa and North Africa/Asia. Geographical variation is considerably affected by sexual dimorphism. Distance-based phylogenetic analysis [neighbour joining (NJ) and UPGMA], constructed from craniometric dissimilarities, not only confirmed the results of multivariate analyses but also fully corroborates current molecular genetic studies. The NJ and UPGMA trees show that the modern lion contains two major evolutionary clusters: the sub-Sahara Africa and North Africa/Asian lion, and also support the Late Pleistocene cave lion (Panthera leo spelaea) and modern lions as two distinct sub-clades, but they are more closely related to each other than to other Panthera. Further investigations focusing on the systematic position of the West African lion are urgently required. © 2010 The Authors. Journal compilation © 2010 The Zoological Society of London.
Mazak J.H.,Shanghai Science and Technology Museum
Mammal Review | Year: 2010
The pantherine cat Panthera palaeosinensis from putative Plio-Pleistocene deposits in North China is one of the oldest known species of Panthera, but its relationship to other Pantherinae is still debated. I compare the holotype skull of P. palaeosinensis with 508 skulls of extant and extinct pantherine cats and show that, when controlling for size, the skull morphology of P. palaeosinensis is most similar to that of the lion Panthera leo or leopard Panthera pardus. Results support the hypothesis that P. palaeosinensis represents a form closely related either to the early lion or leopard clade or to the ancestor of the genus Panthera and suggest an Asian origin for Panthera. © 2010 The Author. Journal compilation © 2010 Mammal Society.
PubMed | Shanghai Science and Technology Museum
Type: Journal Article | Journal: PloS one | Year: 2011
The tiger is one of the most iconic extant animals, and its origin and evolution have been intensely debated. Fossils attributable to extant pantherine species-lineages are less than 2 MYA and the earliest tiger fossils are from the Calabrian, Lower Pleistocene. Molecular studies predict a much younger age for the divergence of modern tiger subspecies at <100 KYA, although their cranial morphology is readily distinguishable, indicating that early Pleistocene tigers would likely have differed markedly anatomically from extant tigers. Such inferences are hampered by the fact that well-known fossil tiger material is middle to late Pleistocene in age. Here we describe a new species of pantherine cat from Longdan, Gansu Province, China, Panthera zdanskyi sp. nov. With an estimated age of 2.55-2.16 MYA it represents the oldest complete skull of a pantherine cat hitherto found. Although smaller, it appears morphologically to be surprisingly similar to modern tigers considering its age. Morphological, morphometric, and cladistic analyses are congruent in confirming its very close affinity to the tiger, and it may be regarded as the most primitive species of the tiger lineage, demonstrating the first unequivocal presence of a modern pantherine species-lineage in the basal stage of the Pleistocene (Gelasian; traditionally considered to be Late Pliocene). This find supports a north-central Chinese origin of the tiger lineage, and demonstrates that various parts of the cranium, mandible, and dentition evolved at different rates. An increase in size and a reduction in the relative size of parts of the dentition appear to have been prominent features of tiger evolution, whereas the distinctive cranial morphology of modern tigers was established very early in their evolutionary history. The evolutionary trend of increasing size in the tiger lineage is likely coupled to the evolution of its primary prey species.