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1.
Sci Total Environ ; 869: 161665, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36657672

RESUMO

Changes in lake area (water surface area) are often considered accurate and sensitive representations of climate change. However, the role that elevation plays in this dynamic is somewhat unclear; studies remain inconclusive as to whether lake responses are consistent across elevation gradients. Here, we used Landsat and keyhole satellite images to quantify lake area changes from the 1960s to 2020 at different elevations in Central Asia's Tianshan Mountains and relate them to both climatic and anthropogenic factors. The results revealed that all low-elevation lakes showed a decreasing trend, and the total area of all monitored low-elevation lakes was reduced by 18.50 %. The total area of the mid-elevation lakes decreased by 0.16 %, while the total area of the high-elevation glacial lakes increased by 4.35 %. Lakes are recharged by a variety of influxes including glacial meltwater and precipitation. Notably, human activities (urban and agricultural water consumption) were the dominant factors in the shrinkage of low-elevation lakes. Climatic factors were the main driving factors of mid-elevation lake changes, and these lakes appeared to be more sensitive to temperature changes than lakes at other elevations. In addition, significant warming dominated area changes in high-elevation proglacial and unconnected glacial lakes. Overall, those results emphasized that when using lakes to reconstruct paleoclimates or predict lake evolution, it is necessary to consider how elevation gradients and recharge types may affect lake sensitivity to variations in climatic and anthropogenic activity.

2.
J Clean Prod ; 158: 367-379, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30294072

RESUMO

Lotus (Newnbo nucifera, Gaertn) is the most important aquatic vegetable in China, with a cultivation history of over 3000 years. The emergy, energy, material, and money flows of three lotus root cultivation modes in Wanqingsha, Nansha District, Guangzhou, China were examined using Energy Systems Language models and emergy evaluation to better understand their ecological and economic characteristics on multiple spatial and temporal scales. The natural resource foundations, economic characteristics and sustainability of these modes were evaluated and compared. The results showed that although all three modes were highly dependent on purchased emergy inputs, their potential impacts as measured by the local (ELRL) and global (ELRW) environmental loading ratios were less than 1.2 and 0.7, respectively. The lotus-fish mode was the most sustainable with its emergy index of sustainable development (EISD) 2.09 and 2.13 times that of the pure lotus and lotus-shrimp modes, respectively. All three lotus-root production modes had superior economic viability, since their Output/Input ratio ranged from 2.56 to 4.95. The results indicated that agricultural systems may have different environmental impacts and sustainability characteristics at different spatial and temporal scales, and that these impacts and characteristics can be simultaneously explored using integrated emergy and economic evaluations.

3.
Zhongguo Zhong Yao Za Zhi ; 33(14): 1649-53, 2008 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-18841757

RESUMO

OBJECTIVE: To study the case of Wisconsin as the top ginseng state in United States which has come through four developing steps: beginning, stagnating, flourishing and now, downturn. METHOD: The current situation of the ginseng industry in Wisconsin was briefly introduced, the federal and state management on ginseng cultivation and export, the organization of Ginseng Board of Wisconsin and their marketing style based on the field investigation and data collected from USDA and Wisconsin state. RESULT: The advantages and disadvantages of Wisconsin ginseng industry were analyzed in order to provide some suggestions for Chinese medicine industry. CONCLUSION: Chinese ginseng industry should learn the organization system from Wisconsin.


Assuntos
Indústria Farmacêutica/organização & administração , Panax , Indústria Farmacêutica/economia , Indústria Farmacêutica/história , Medicamentos de Ervas Chinesas/economia , Medicamentos de Ervas Chinesas/história , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Estados Unidos
4.
Zhonghua Gan Zang Bing Za Zhi ; 14(3): 169-73, 2006 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-16556408

RESUMO

OBJECTIVE: To develop a diagnostic model comprising clinical and serum markers for assessing HBV-related liver fibrosis. METHODS: 270 chronic hepatitis B patients were randomly allocated to either an estimation group (195 cases) or a validation group (75 cases). Liver biopsies were done and staging of fibrosis was assessed. Twenty-six common clinical and serum markers were analyzed initially in the estimation group to derive a predictive model to discriminate the stages of fibrosis. The model created was then assessed with ROC analysis. It was also applied to the validation group to test its accuracy. RESULTS: Among 13 variables associated with liver fibrosis selected by univariate analysis, age, gamma glutamyltranspeptidase (GGT), hyaluronic acid (HA), and platelet count (PLT) were identified by multivariate logistic regression analysis as independent factors of fibrosis. A fibrosis index constructed from the above four markers was established. In ROC analysis, the AUC was 0.889 for the estimation group and 0.850 for the validation group for discriminating > or =S3 from < or=S2. Using the optimal cutoff score 3.0, the sensitivity of the index was 90.2%, the specificity 76.1%, and the accuracy was 82%. There was a positive linear relationship between the index scores and the fibrosis stages (r = 0.731, P<0.001). The AUC for identifying > or=S2 was 0.873 with sensitivity/specificity of 79%/82%, cutoff score 2.2; The AUC for identifying S4 was 0.872 with sensitivity/specificity of 83%/75%, cutoff score 5.4. There were no significant differences in diagnostic efficacy in the model between the estimation and the validation group (P>0.05). CONCLUSION: A model for assessment of liver fibrosis was established with easily accessible markers. It appears to be sensitive, accurate and reproducible, suggesting it could be used to assist or replace liver biopsy to detect dynamic changes of HBV-related liver fibrosis.


Assuntos
Hepatite B Crônica/diagnóstico , Cirrose Hepática/diagnóstico , Adolescente , Adulto , Idoso , Feminino , Previsões , Hepatite B Crônica/complicações , Humanos , Cirrose Hepática/etiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade
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