987 resultados para economic sentiment indicator


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In recent years, the role of human activities in changing sediment yield has become more apparent for the construction of hydraulic engineering and water conservation projections in the Upper Yangtze River, but it has not been evaluated at the macro scale. Taking Sichuan Province and Chongqing City as an example, this paper studies the relationship between socio-economic factors and sediment yield in the Upper Yangtze River based on section data in 1989 and 2007. The results show that sediment yield is significantly correlated with population density and cultivated area, in which the former appears to be more closely related to sediment yield. Moreover, in the relation of sediment yield vs. population density, a critical value of population density exists, below which the sediment yield increases with the increase of population density and over which the sediment yield increases with the decrease of population density. The phenomenon essentially reflects the influence of natural factors, such as topography, precipitation and soil property, and some human activities on sediment yield. The region with a higher population density than critical value is located in the east of the study area and is characterized by plains, hills and low mountains, whereas the opposite is located in the west and characterized by middle and high mountains. In the eastern region, more people live on the lands with a low slope where regional soil erosion is slight; therefore, sediment yield is negatively related with population density. In contrast, in the western region, the population tends to aggregate in the areas with abundant soil and water resources which usually lead to a higher intensity of natural erosion, and in turn, high-intensity agricultural practices in these areas may further strengthen local soil erosion. It is also found that population tends to move from the areas with bad environment and high sediment yield to the areas with more comfortable environment and less sediment yield. The natural factors have greater influence on sediment yield of western region than that of eastern region. Generally, the natural factors play a dominant role on sediment yield in the Upper Yangtze River.

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Spatial relations, reflecting the complex association between geographical phenomena and environments, are very important in the solution of geographical issues. Different spatial relations can be expressed by indicators which are useful for the analysis of geographical issues. Urbanization, an important geographical issue, is considered in this paper. The spatial relationship indicators concerning urbanization are expressed with a decision table. Thereafter, the spatial relationship indicator rules are extracted based on the application of rough set theory. The extraction process of spatial relationship indicator rules is illustrated with data from the urban and rural areas of Shenzhen and Hong Kong, located in the Pearl River Delta. Land use vector data of 1995 and 2000 are used. The extracted spatial relationship indicator rules of 1995 are used to identify the urban and rural areas in Zhongshan, Zhuhai and Macao. The identification accuracy is approximately 96.3%. Similar procedures are used to extract the spatial relationship indicator rules of 2000 for the urban and rural areas in Zhongshan, Zhuhai and Macao. An identification accuracy of about 83.6% is obtained.

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In this paper, a simple, label-free and regenerative method was proposed to study the interaction between aptamer and small molecule by using methylene blue (MB+) as an electrochemical indicator. A thiolated capture probe containing twelve bases was firstly self-assembled on gold electrode by gold-sulfur affinity. Aptamer probe containing thirty two bases, which was designed to hybridize with capture DNA sequence and specifically recognize adenosine, was then immobilized on the electrode surface by hybridization reaction. MB+ was abundantly adsorbed on the aptamer probe by the specific interaction between MB+ and guanine base in aptamer probe. MB+-anchored aptamer probe can be forced to dissociate from the sensing interface after adenosine triggered structure switching of the aptamer. The peak current of MB+ linearly decreased with the concentration of adenosine over a range of 2 x 10 (8)- x 10 (6) M with a detection limit of 1 x 10 (8) M. In addition, we examined the selectivity of this electrochemical biosensor for cytidine, uridine and guanosine that belonged to the nucleosides family and possessed 1 similar structure with adenosine.

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The assessment of sustainable development is a challenging task as its measuring is rather complex without a mature framework. In this paper, as a case study, a coastal city of China-Yantai was assessed for sustainable development in the period from 1998 to 2007. We used a methodological framework based on 36 indicators and three composite indices from the dimensions of environment, economy and society subsystems. The assessment results indicated that Yantai was almost in the potentially unsustainable development or intermediate sustainable development, except in 1998 and in 2007. Accordingly, the progress of sustainable development was divided into two stages in the light of the relative changes of three subsystems. Some relevant issues, such as natural capital, GPI vs. GDP in sustainable development assessment were discussed. Finally, an uncertainty analysis was also given in the assessment. In conclusion, the sustainable development in Yantai had experienced a shift from environment-based to social-economic-based in the past 10 years. (C) 2010 Elsevier Ltd. All rights reserved.

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Laboratory studies have shown that Antarctic krill (Euphausia superba) shrink if maintained in conditions of low food availability. Recent studies have also demonstrated that E. superba individuals may be shrinking in the field during winter. If krill shrink during the winter, conclusions reached by length-frequency analysis may be unreliable because smaller animals may not necessarily be younger animals. In this study, the correlation between the body-length and the crystalline cone number of the compound eye was examined. Samples collected in the late summer show an apparent linear relationship between crystalline cone number and body-length. From a laboratory population, it appears that when krill shrink the crystalline cone number remains relatively unchanged. If crystalline cone number is little affected by shrinking, then the crystalline cone number may be a more reliable indicator of age than body-length alone. The ratio of crystalline cone number to body-length offers a method for detecting the effect of shrinking in natural populations of krill. On the basis of the crystalline cone number count, it appears from a field collection in early spring that E. superba do shrink during winter.

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Fucoidan, a group of sulfated heteropolysaccharide, was extracted from Laminaria japonica, an important economic alga species in China. Three sulfated polysaccharide fractions (F1, F2, and F3) were successfully isolated through anion-exchange column chromatography and had their antioxidant activities investigated employing various established in vitro systems, including superoxide and hydroxyl radical scavenging activity, chelating ability, and reducing power. Chemical analysis suggested that F1 and F3 were heteropolysaccharide in which galactose was the major component, while F2 was a typical fucoidan. All fractions possessed considerable antioxidant activity, and F1, F2 and F3 had stronger antioxidant ability than fucoidan in certain tests. The correlation between the sulfate content and scavenging superoxide radical ability was positive. Available data obtained with in vitro models suggested that the ratio of sulfate content/fucose was an effective indicator to antioxidant activity of the samples. (C) 2007 Elsevier B.V. All rights reserved.

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Our goal was to determine the effect of diets with different crude protein (CP) contents and metabolizable energy (W) levels on daily live-weight gain, apparent digestibility, and economic benefit of feedlot yaks on the Tibetan plateau during winter. Yaks were either 2- or 3-years old and randomly selected from the same herd. The 3-year-olds were placed into one of two experimental groups (A and B) and a control (CK1), and the two-year-olds were placed into one of three experimental groups (C, D and E) and a control (CK2) (N per group = 5). Yak in the control groups were allow graze freely, while those in the experimental groups yaks were fed diets higher in contains crude protein and metabolizable energy through a winter period inside a warming shed. Results indicated that live-weight gain of treatment groups was higher than their respective controls during experiment, and that daily live-weight gain of every 10 days among different treatments was significant difference (P < 0.05). In addition, apparent digestibility of different diets was linearly and positively related to feedlotting time, and feed conversion efficiency for A, C, D and E groups was quadratically related to feedlotting time (P < 0.01), however, feed conversion efficiency for B group was linearly and positively related to feedlotting time (P < 0.05). The economic benefit was 1.15 for A, 1.89 for B, 1.16 for C, 1.54 for D, and 4,52 for E. (c) 2005 Elsevier B.V. All rights reserved.

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Understanding relationship between environmental protection and economic development is crucial to form practical environmental policy. At micro level, implementation of environmental regulations often causes production mills adjustment of technology which might leads to change of productive efficiency and cost, which, in turn, determine effort level of mills and even local government in pollution control. Using a stochastic frontier production model and a set of survey data on 126 paper mills from six provinces of China, we measure the technical efficiency changes and analyze the determinants of efficiency. in particular, we examine impact of environmental policy on paper mills' efficiency, using an indicator of environmental policy-the levy ratio of COD. We also estimate a simultaneous-equation model in which the levy rate and emission are jointly determined. The results indicate that there have been efficiency improvements during 1999-2003, when enforcement of environmental regulations have been tightened. The impacts, nevertheless, are different for different types of mills. We also find the levy ratio, which is influenced by both the local social and economic conditions and the characters of paper mills, such as scale, has strong impact on the abatement of the pollutant-COD. Additionally, paper mills' technical efficiency has positive effect on the reduction of the emission intensity of the pollutant-COD. These results lead a set of implications pertinent to policy improvement.

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Risk perception is one of important subjects in management psychology and cognitive psychology. It is of great value in the theory and practice to investigate the social risk events that the public cares a lot especially in this social transition period. Furthermore, this study explored the factors that influence the risk perception and the results caused by risk perception. A survey including 30 hazards and 8 risk attributes was designed and distributed to about 3, 200 residents of 8 districts, Beijing. The major findings are listed as following: Firstly, combining the methods of system science and psychology, GAE program was used to indentify 7 groups of social risk events, such as national safe, government management, social stability, general mood of society, economic and finance, resources and environment & daily life problems. This study provided substance for the following studies and it was also a new attempt in research method which is of certain reference value for the related researches. Secondly, a scale of societal risk perception was designed and 2 factors were identified (Dread Risk & Unknown Risk). Reliability analysis, EFA and CFA show the reliability and validity of the societal risk questionnaire is good enough. The investigation using this scale showed that older participants and higher socioeconomic status perceived the societal hazards to be more threatening than did younger participants and lower socioeconomic status. However, there is no gender difference. Thirdly, structural equation model was used to analyze the influence factors and mechanism of societal risk perception. Risk taking, government support and social justice could influence societal risk perception directly. Government support moderated the relationship between government trust and societal risk perception. Societal risk perception influenced life satisfaction, public policy preferences and social development belief. Multi-group analysis was used to find out that the participants who have different socioeconomic status express different mechanism. Fourthly, the result of the research was used to explore the risk event of 2008 Olympic game. The results showed that government support and preparation of Olympic game influenced societal risk perception directly. Preparation moderated the relationship between government trust and risk perception. Risk perception influenced worry, effect of Olympic game and belief of successl. This result proved that risk perception could be used as an indicator. The indictor of risk perception was used to identify the characteristics of higher risk perception group. Finally, suggestions to the related decision were provide to the government.

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Grattan, J.P., Gilbertson, D.D., Hunt, C.O. (2007). The local and global dimensions of metaliferrous air pollution derived from a reconstruction of an 8 thousand year record of copper smelting and mining at a desert-mountain frontier in southern Jordan. Journal of Archaeological Science 34, 83-110