60 research outputs found

    Chromosomal rearrangements and karyotype evolution in carnivores revealed by chromosome painting

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    Chromosomal evolution in carnivores has been revisited extensively using cross-species chromosome painting. Painting probes derived from flow-sorted chromosomes of the domestic dog, which has one of the most rearranged karyotypes in mammals and the highest dipoid number (2n=78) in carnivores, are a powerful tool in detecting both evolutionary intra- and inter-chromosomal rearrangements. However, only a few comparative maps have been established between dog and other non-Canidae species. Here, we extended cross-species painting with dog probes to seven more species representing six carnivore families: Eurasian lynx (Lynx lynx), the stone marten (Martes foina), the small Indian civet (Viverricula indica), the Asian palm civet (Paradoxurus hermaphrodites), Javan mongoose (Hepestes javanicas), the raccoon (Procyon lotor) and the giant panda (Ailuropoda melanoleuca). The numbers and positions of intra-chromosomal rearrangements were found to differ among these carnivore species. A comparative map between human and stone marten, and a map among the Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis), stone marten and human were also established to facilitate outgroup comparison and to integrate comparative maps between stone marten and other carnivores with such maps between human and other species. These comparative maps give further insight into genome evolution and karyotype phylogenetic relationships among carnivores, and will facilitate the transfer of gene mapping data from human, domestic dog and cat to other species

    Growth disturbance of extracts from several crops straw (residue) on Ageratina adenophora and biological-control implications in hazardous weed invasion for eco-restoration

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    Laboratory biological simulation experiment was conducted to investigate growth disturbance of high, moderate, low concentration of aqueous extracts (i.e. the original extracts with a solid liquid ratio of 1:40 g mL-1 and its 5 times diluents and 25 times diluents) from several crops straw (residue) on Ageratina adenophora, a worldwide notorious invasive weed. The results showed: (a) aqueous extracts from several crops straw (residue) brought about different impacts on the single index for germination and growth of A. adenophora, e.g., high concentration of aqueous extracts from Brassica oleracea waste leaves showed a strong inhibition against the germination rate (GR) and germination index (GI) of A. adenophora, while high concentration of aqueous extracts from Vicia cracca straw showed a strong inhibition against radicle length (RL) and hypocotyl length (HL) of A. adenophora; (b) high concentration of aqueous extracts from B. oleracea waste leaves and high, moderate and low concentration of aqueous extracts from Oryza sativa straw and Triticum aestivum straw showed rather strong synthetic effects (inhibition) on GR and GI of A. adenophora, which could be chosen for the control over the seeds germination of A. adenophora; (c) high and moderate concentrations of aqueous extracts from V. cracca straw, high concentration of aqueous extracts from B. campestris waste leaves, and moderate and low concentrations of aqueous extracts from O. sativa straw and T. aestivum straw showed rather strong synthetic effects (inhibition) on RL and HL of A. adenophora, which could be selected as ideal materials for the control over the seedlings growth of A. adenophora; and (d) high concentrations of aqueous extracts from V. cracca straw, B. oleracea waste leaves and B. campestris waste leaves, and high, moderate and low concentrations of aqueous extracts from O. sativa straw and T. aestivum straw showed rather strong synthetic effects (inhibition) on GR, GI, RL and HL of A. adenophora, which could be selected as ideal materials for the control over the seeds germination and seedlings growth of A. adenophora. Thus, this study would provide a theoretic guidance and technical support for the resources utilization of crops straw (residue) and the prevention and control over invasive weeds as well. (C) 2013 Elsevier B.V. All rights reserved.Laboratory biological simulation experiment was conducted to investigate growth disturbance of high, moderate, low concentration of aqueous extracts (i.e. the original extracts with a solid liquid ratio of 1:40 g mL-1 and its 5 times diluents and 25 times diluents) from several crops straw (residue) on Ageratina adenophora, a worldwide notorious invasive weed. The results showed: (a) aqueous extracts from several crops straw (residue) brought about different impacts on the single index for germination and growth of A. adenophora, e.g., high concentration of aqueous extracts from Brassica oleracea waste leaves showed a strong inhibition against the germination rate (GR) and germination index (GI) of A. adenophora, while high concentration of aqueous extracts from Vicia cracca straw showed a strong inhibition against radicle length (RL) and hypocotyl length (HL) of A. adenophora; (b) high concentration of aqueous extracts from B. oleracea waste leaves and high, moderate and low concentration of aqueous extracts from Oryza sativa straw and Triticum aestivum straw showed rather strong synthetic effects (inhibition) on GR and GI of A. adenophora, which could be chosen for the control over the seeds germination of A. adenophora; (c) high and moderate concentrations of aqueous extracts from V. cracca straw, high concentration of aqueous extracts from B. campestris waste leaves, and moderate and low concentrations of aqueous extracts from O. sativa straw and T. aestivum straw showed rather strong synthetic effects (inhibition) on RL and HL of A. adenophora, which could be selected as ideal materials for the control over the seedlings growth of A. adenophora; and (d) high concentrations of aqueous extracts from V. cracca straw, B. oleracea waste leaves and B. campestris waste leaves, and high, moderate and low concentrations of aqueous extracts from O. sativa straw and T. aestivum straw showed rather strong synthetic effects (inhibition) on GR, GI, RL and HL of A. adenophora, which could be selected as ideal materials for the control over the seeds germination and seedlings growth of A. adenophora. Thus, this study would provide a theoretic guidance and technical support for the resources utilization of crops straw (residue) and the prevention and control over invasive weeds as well. (C) 2013 Elsevier B.V. All rights reserved

    Eucalyptus Trees - Ageratina adenophora Complex System: A New Eco-environmental Protection Model

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    Eucalyptus trees and Ageratina adenophora complex system, a new ecological phenomenon that is worthy of attention, was proposed firstly in this paper, and some scientific problems were summarized from the new phenomenon. Causes of the new phenomenon were analyzed tentatively from the perspective of ecology. It was pointed out that ecological degradation of Eucalyptus plantation and strong invasiveness of A. adenophora are two apparent reasons for formation of Eucalyptus trees and A. adenophora complex system. Basic view of the authors on causes of the new phenomenon was put forward that resistance unbalance between chemical defensive potential of Eucalyptus trees and chemical invasive potential of A. adenophora might be the fundamental reason for formation of Eucalyptus trees and A. adenophora complex system, based on the two apparent reasons respectively connected with allelopathic effects of Eucalyptus trees and A. adenophora as dominant species of the complex system. Some proofs from studies on chemical components and biological activities of Eucalyptus species and A. adenophora have proved the basic view of the authors. It was discussed that formation of the complex system would influence some environmental elements such as soil environment, hydrology environment, and biology environment. It was proposed that three key scientific issues, namely chemical mechanism of formation of the complex system, ecological effects of formation of the complex system, and succession trends and impact factors of the complex system should be mainly studied as special researches to probe ecological relationship of exotic species because of absence study on the complex system and objective requirements of production practice in future. It was emphasized that the proposed researches might be of guidance significance to scientific management and sustainable operation of Eucalyptus plantation under the condition of biological invasion.Eucalyptus trees and Ageratina adenophora complex system, a new ecological phenomenon that is worthy of attention, was proposed firstly in this paper, and some scientific problems were summarized from the new phenomenon. Causes of the new phenomenon were analyzed tentatively from the perspective of ecology. It was pointed out that ecological degradation of Eucalyptus plantation and strong invasiveness of A. adenophora are two apparent reasons for formation of Eucalyptus trees and A. adenophora complex system. Basic view of the authors on causes of the new phenomenon was put forward that resistance unbalance between chemical defensive potential of Eucalyptus trees and chemical invasive potential of A. adenophora might be the fundamental reason for formation of Eucalyptus trees and A. adenophora complex system, based on the two apparent reasons respectively connected with allelopathic effects of Eucalyptus trees and A. adenophora as dominant species of the complex system. Some proofs from studies on chemical components and biological activities of Eucalyptus species and A. adenophora have proved the basic view of the authors. It was discussed that formation of the complex system would influence some environmental elements such as soil environment, hydrology environment, and biology environment. It was proposed that three key scientific issues, namely chemical mechanism of formation of the complex system, ecological effects of formation of the complex system, and succession trends and impact factors of the complex system should be mainly studied as special researches to probe ecological relationship of exotic species because of absence study on the complex system and objective requirements of production practice in future. It was emphasized that the proposed researches might be of guidance significance to scientific management and sustainable operation of Eucalyptus plantation under the condition of biological invasion

    A temporally cyclic growth model of urban spatial morphology in China: evidence from Kunming Metropolis

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    Rapid urbanization and complexity of political-economic transition in China has brought about continuous and remarkable changes of urban morphology over the past decades, which were driven by a mixture of spatial, social-economic and institutional forces. Understanding such urban morphological evolution requires new mixed evidences and holistic perspectives. In this paper, it is argued that two dominant types of urban growth in China: low-density expansion and high-density infill might be driven by different forces at different stages. To interpret the processes of urban development, two easy-to-understand morphological indicators: expansion-induced investment density index” (EID) and “infill-induced investment density index” (IID) are defined to measure the investment density per unit of developed land and used to compare the morphological changes between different phases in a long period by integrating spatial and socio-economic data. The temporal variation of these indicators suggests a cyclic growth model (CGM), which means the periodic switch between low density expansion and high-density infill. Using Kunming metropolis as a case study, this paper has confirmed that its urban morphological evolution from 1950-2014 was periodically and reciprocally driven by a set of vis-à-vis dualistic dynamics, in which low-density expansion is led by pro-growth infrastructure oriented public investment, while the high-density infill is activated by collective and rational actions of individual enterprises and their economic behaviors. It is concluded that the confirmed CGM model, together with two morphological indicators, offers a new holistic perspective and method to easily and integrally interpret urban morphological evolution and accordingly has potential theoretical implications for reasonably understanding the urbanisation in China

    Long-term Monitoring on Mrk 501 for Its VHE gamma Emission and a Flare in October 2011

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    As one of the brightest active blazars in both X-ray and very high energy γ\gamma-ray bands, Mrk 501 is very useful for physics associated with jets from AGNs. The ARGO-YBJ experiment is monitoring it for γ\gamma-rays above 0.3 TeV since November 2007. Starting from October 2011 the largest flare since 2005 is observed, which lasts to about April 2012. In this paper, a detailed analysis is reported. During the brightest γ\gamma-rays flaring episodes from October 17 to November 22, 2011, an excess of the event rate over 6 σ\sigma is detected by ARGO-YBJ in the direction of Mrk 501, corresponding to an increase of the γ\gamma-ray flux above 1 TeV by a factor of 6.6±\pm2.2 from its steady emission. In particular, the γ\gamma-ray flux above 8 TeV is detected with a significance better than 4 σ\sigma. Based on time-dependent synchrotron self-Compton (SSC) processes, the broad-band energy spectrum is interpreted as the emission from an electron energy distribution parameterized with a single power-law function with an exponential cutoff at its high energy end. The average spectral energy distribution for the steady emission is well described by this simple one-zone SSC model. However, the detection of γ\gamma-rays above 8 TeV during the flare challenges this model due to the hardness of the spectra. Correlations between X-rays and γ\gamma-rays are also investigated.Comment: have been accepted for publication at Ap

    Data underlying the publication: Spatial pattern recognition of local high temperature increases in mountain areas based on MODIS land surface temperature images

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    Finding out local high temperature increase (HTI) is&nbsp;significant for exploiting and conserving mountain climatic resources. &nbsp;We proposes&nbsp;an image pattern recognition method to identify&nbsp;the&nbsp;HTI zones&nbsp;by GIS and RS technologies, and used the method to produce HTI fileds, HTI strips and other auxiliary data of Yunnan Province, China. The research paper described the method and these data will be submit to the our objective SCI magazine.&nbsp; Therefore, this dataset contains all available data of our submission manuscript.</p

    Data underlying the publication: Spatial pattern recognition of local high temperature increases in mountain areas based on MODIS land surface temperature images

    No full text
    Finding out local high temperature increase (HTI) is&nbsp;significant for exploiting and conserving mountain climatic resources. &nbsp;We proposes&nbsp;an image pattern recognition method to identify&nbsp;the&nbsp;HTI zones&nbsp;by GIS and RS technologies, and used the method to produce HTI fileds, HTI strips and other auxiliary data of Yunnan Province, China. The research paper described the method and these data will be submit to the our objective SCI magazine.&nbsp; Therefore, this dataset contains all available data of our submission manuscript.</p

    The Inverse Problem of Sensing the Mass and Force induced by an Adsorbate on a Beam Nanomechanical Resonator

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    The mass sensing superiority of a micro/nanomechanical resonator sensor over conventional mass spectrometry has been, or at least, is being firmly established. Because the sensing mechanism of a mechanical resonator sensor is the shifts of resonant frequencies, how to link the shifts of resonant frequencies with the material properties of an analyte formulates an inverse problem. Besides the analyte/adsorbate mass, many other factors such as position and axial force can also cause the shifts of resonant frequencies. The in-situ measurement of the adsorbate position and axial force is extremely difficult if not impossible, especially when an adsorbate is as small as a molecule or an atom. Extra instruments are also required. In this study, an inverse problem of using three resonant frequencies to determine the mass, position and axial force is formulated and solved. The accuracy of the inverse problem solving method is demonstrated and how the method can be used in the real application of a nanomechanical resonator is also discussed. Solving the inverse problem is helpful to the development and application of mechanical resonator sensor on two things: reducing extra experimental equipments and achieving better mass sensing by considering more factors
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