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Guan D.,Saga University | Gao W.,University of Kitakyushu | Su W.,Chongqing Normal University | Su W.,Guizhou Academy of science | And 2 more authors.
Ecological Indicators | Year: 2011

At present, environmental issues associated with rapid economic development are becoming critical concerns that arouse government's and people's particular attention. A large amount of influencing factors and especially their complicated interactions have always thrown confused insights into assessing the dynamic evolvement and sustainable development of urban economy-resource- environment (ERE) system and programming the developing strategies. A combination of system dynamics (SD) and geographic information system (GIS) is expected to explicitly understand the synergic interaction and feedback among a variety of influencing factors in time and space, since SD model can extend the spatial analysis functions of GIS to realize both dynamic simulation and trend prediction of an ERE system development. According to connotation and framework of sustainable development, this study proposes a dynamic combination method of SD-GIS to model and evaluate the urban development in Chongqing city of China suffering from depletion of resource and degradation of environment. To compare different policy inclinations with regard to potential ERE effects, typical scenarios (current, resource, technology and environment scenarios) are designed by adjusting the parameters in the model and changing the specification of some variables. Integrated assessment results indicate that the current ERE system of Chongqing is not sustainable; environment scenario is more effective to sustainable development of urban ERE system in a long run. Under the considerations of development features and regional differences, as well as regular discipline on urbanization, a coordinated combination of environmental, resource and technology scenarios is anticipated to realize sustainable development of urban ERE system. © 2011 Elsevier Ltd. Source

Zhang P.,Guizhou Academy of science | Zhang P.,French Natural History Museum | Huang W.,CAS Institute of Vertebrate Paleontology and Paleoanthropology | Wang W.,Guangxi Natural Historical Museum
Quaternary International | Year: 2010

Fengshudao (Guangxi province, southern China), adjacent to the northern part of the Bose basin, has yielded a lithic assemblage rich in handaxes. Through tektite dating, the site is estimated at 800. ka. The study provides elements regarding the technical characteristics of this material, giving evidence that an Acheulian population (practicing the mode II technology) settled in Fengshudao. This lithic assemblage clearly prefigures parts of the Levallois operating procedure. © 2009 Elsevier Ltd and INQUA. Source

Zhang Z.,Guizhou Academy of science
Tezhong Zhuzao Ji Youse Hejin/Special Casting and Nonferrous Alloys | Year: 2014

Microstructure of a new Al-Cu-Mn high strength aluminum alloy was investigated by metallurgical microscope, transmission electron microscope (TEM), scanning electron microscopy (SEM), electron diffraction and energy spectrum (EDS), XRD(X-ray diffraction). The results reveal that θ' precipitate phase is dominant in the alloy with some θ disperoids. The dispersedly fine T-Al12Mn2Cu phase can be observed in the microstructure, playing a role in dispersed strengthening. In addition, Cd particle with approximately 2 nm in size can be observed in the matrix phase to promote the nucleation and growth of strengthening phase. Microstructure of the alloy is composed of equaixed crystal with 30~80 μm, meanwhile, texture is absent apparently. EDS analysis reveals that there exists composition segregation, and RE element is mainly segregated at the grain boundary. PFZ zone can be observed in the alloy, and fine needle N phase with μm level in size is precipitated from the grain boundary, which can decrease the elongation of the alloy. So the quantity of the brittle phase should be decreased as possible. Source

Wang Y.,Guizhou University | Zhang Y.,University of Western Sydney | Zhou Y.,University of Western Sydney | Zhang M.,Guizhou Academy of science
13th International Conference on the Principles of Knowledge Representation and Reasoning, KR 2012 | Year: 2012

In this paper, we propose a semantic forgetting for arbitrary logic programs (or propositional theories) under answer set semantics, called HT-forgetting. The HT-forgetting preserves strong equivalence in the sense that strongly equivalent logic programs will remain strongly equivalent after forgetting the same set of atoms. The result of an HT-forgetting is always expressible by a logic program, and in particular, the result of an HT-forgetting in a Horn program is expressible in a Horn program; and a representation theorem shows that HT-forgetting can be precisely characterized by Zhang-Zhou's four forgetting postulates under the logic of here-and-there. We also reveal underlying connections between HT-forgetting and classical forgetting, and provide complexity results for decision problems. Copyright © 2012, Association for the Advancement of Artificial Intelligence (www.aaai.org). All rights reserved. Source

Wang Y.,Affiliated Hospital of Guiyang Medical College | Cheng M.,Affiliated Hospital of Guiyang Medical College | Zhang B.,Affiliated Hospital of Guiyang Medical College | Nie F.,Guizhou Academy of science | Jiang H.,Affiliated Hospital of Guiyang Medical College
PLoS ONE | Year: 2013

Aim: To investigate the effect of blueberry juice intake on rat liver fibrosis and its influence on hepatic antioxidant defense. Methods: Rabbiteye blueberry was used to prepare fresh juice to feed rats by daily gastric gavage. Dan-shao-hua-xian capsule (DSHX) was used as a positive control for liver fibrosis protection. Liver fibrosis was induced in male Sprague-Dawley rats by subcutaneous injection of CCl4 and feeding a high-lipid/low-protein diet for 8 weeks. Hepatic fibrosis was evaluated by Masson staining. The expression of α-smooth muscle actin (α-SMA) and collagen III (Col III) were determined by immunohistochemical techniques. The activities of superoxide dismutase (SOD) and malondialdehyde (MDA) in liver homogenates were determined. Metallothionein (MT) expression was detected by real-time RT-PCR and immunohistochemical techniques. Results: Blueberry juice consumption significantly attenuates CCl4-induced rat hepatic fibrosis, which was associated with elevated expression of metallothionein (MT), increased SOD activity, reduced oxidative stress, and decreased levels of α-SMA and Col III in the liver. Conclusion: Our study suggests that dietary supplementation of blueberry juice can augment antioxidative capability of the liver presumably via stimulating MT expression and SOD activity, which in turn promotes HSC inactivation and thus decreases extracellular matrix collagen accumulation in the liver, and thereby alleviating hepatic fibrosis. © 2013 Wang et al. Source

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