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1.
Huan Jing Ke Xue ; 44(8): 4647-4654, 2023 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-37694657

RESUMO

The literature from a long-term fertilization experiment in the Yangtze River Economic Belt from January 1992 to May 2022 was collected, and the data of farmland soil organic carbon were extracted and integrated. Using the normalization treatment and the analysis method of relative annual variation, the overall change in soil organic carbon content in farmland in the Yangtze River Economic Belt under different long-term fertilization measures was studied, and the change differences of soil organic carbon content under three tillage modes were compared so as to judge and analyze the influence of the duration of the experiment on soil organic carbon dynamics. The results showed that under different long-term fertilization measures, the organic carbon content of farmland soil in the Yangtze River Economic Belt in China showed an overall upward trend. The NP, NPK, O, and NPKO treatments all increased the organic carbon content of agricultural soils, with that of the NPKO treatment being the largest. The sole application of inorganic nitrogen fertilizer reduced the organic carbon content of the soil. The rates of change in soil organic carbon content were 0.22 g·(kg·a)-1, 0.24 g·(kg·a)-1, and 0.16 g·(kg·a)-1for dryland, paddy, and water-dry rotation farmland, respectively. Additionally, the relatively rapid increase effect of organic carbon brought by the O and NPKO treatments could last for no more than 28 years in dryland soil but could still last for more than 28 years in paddy field and paddy-upland rotation soil. There was some variation in the rate of change of soil organic carbon content between soil types. The average rate of change of organic carbon was 0.25 g·(kg·a)-1for red soils, 0.14 g·(kg·a)-1 for brown soils, 0.19 g·(kg·a)-1 for tidal soils, and 0.15 g·(kg·a)-1 for rice soils. The trend of NPKO>O>NPK>NPK>NP>N was basically maintained for the rate of change in soil organic carbon content. The NPKO treatments were all significantly higher than the chemical fertilizer (N, NP, and NPK) treatments alone. The N treatment showed a reduction in organic carbon content in both red soil and rice soils. Considering the carbon fixation of farmland soil, the combined application of organic and inorganic fertilizers is a more suitable fertilization method in this area.

2.
Environ Sci Technol ; 56(17): 12656-12666, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35943862

RESUMO

Global dairy production, consumption, and trade are growing rapidly, driven by population and per capita income growth and increasing health concerns mainly from developing countries, which has aroused concerns about the related carbon emission (mostly in the form of methane) increase. If all of the dairy products consumed were produced locally/domestically in the developing countries/economies (a counterfactual scenario), the carbon emissions in 2018 would be 28 Mt CO2-equiv higher than its status quo (a factual scenario). The present study indicates that unlike in many global trade cases in which carbon leakages are from developed to developing countries, global dairy trade is characterized by net embodied carbon flows from developed to developing countries/economies due to the fact that there is an overwhelming one-way-flow of dairy products from developed to developing countries/economies. The differences in the carbon emission factors between the developed and developing countries/economies provide an opportunity that global dairy trade and production specialization can help to reduce carbon emissions from increasing dairy product demand, and the total reduction potential is estimated to be about 414 Mt CO2-equiv from 2018 to 2030. Free trade agreements such as the Regional Comprehensive Economic Partnership will incentivize larger carbon emission reduction benefits through promoting dairy trade.


Assuntos
Dióxido de Carbono , Carbono , Comércio , Desenvolvimento Econômico , Renda
3.
Sci Rep ; 12(1): 5316, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35351951

RESUMO

Early detection of keratoconus is a crucial factor in monitoring its progression and making the decision to perform refractive surgery. The aim of this study was to use the decision tree technique in the classification and prediction of subclinical keratoconus (SKC). A total of 194 eyes (including 105 normal eyes and 89 with SKC) were included in the double-center retrospective study. Data were separately used for training and validation databases. The baseline variables were derived from tomography and biomechanical imaging. The decision tree models were generated using Chi-square automatic interaction detection (CHAID) and classification and regression tree (CART) algorithms based on the training database. The discriminating rules of the CART model selected metrics of the Belin/Ambrósio deviation (BAD-D), stiffness parameter at first applanation (SPA1), back eccentricity (Becc), and maximum pachymetric progression index in that order; On the other hand, the CHAID model selected BAD-D, deformation amplitude ratio, SPA1, and Becc. Further, the CART model allowed for discrimination between normal and SKC eyes with 92.2% accuracy, which was higher than that of the CHAID model (88.3%), BAD-D (82.0%), Corvis biomechanical index (CBI, 77.3%), and tomographic and biomechanical index (TBI, 78.1%). The discriminating performance of the CART model was validated with 92.4% accuracy, while the CHAID model was validated with 86.4% accuracy in the validation database. Thus, the CART model using tomography and biomechanical imaging was an excellent model for SKC screening and provided easy-to-understand discriminating rules.


Assuntos
Ceratocone , Córnea/diagnóstico por imagem , Paquimetria Corneana/métodos , Topografia da Córnea/métodos , Árvores de Decisões , Humanos , Ceratocone/diagnóstico por imagem , Curva ROC , Estudos Retrospectivos , Tomografia/métodos
4.
Huan Jing Ke Xue ; 42(1): 147-158, 2021 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-33372466

RESUMO

The pollution characteristics of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and phthalate esters (PAEs) in the surface sediments of Xiaoxingkai Lake were analyzed by GC-MS, and the main sources and biological toxicity risks of the pollutants were discussed. The results show that:① The content of PAHs in the sediments of xiaoxingkai lake ranged from 82.1 to 534.6 ng·g-1, and the concentration of PAHs in the northwestern port of the lake was higher. The content of OCPs and PAEs in the sediments ranged from 4.8 to 50.4 ng·g-1 and 33.3 to 401.6 ng·g-1, respectively. The concentration was higher in the southeastern lakes. ② PAHs in the sediments were dominated by 3-5-ring compounds (accounting for more than 85%), which were mainly combustion sources, among which the combustion of coal and firewood contributed 47%, the combustion of gasoline and diesel contributed 39%, and the oil product leakage contributed 14%. The OCPs were mainly HCHs (78%) from the use of new lindane and the input of a small amount of industrial HCHs. The PAEs were mainly dibutyl phthalate (DBP) and diethyl phthalate (2-ethyl hexyl) ester (DEHP; 94%), which were mainly derived from household garbage and common human articles. ③ Compared with other lakes in China, PAHs and PAEs in the sediments of Xiaoxingkai Lake are at a low pollution level, and there is no ecological risk at present, but some OCPs at some points present a moderate ecological risk.


Assuntos
Hidrocarbonetos Clorados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Hidrocarbonetos Clorados/análise , Lagos , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Rios , Poluentes Químicos da Água/análise
5.
Biomed Res Int ; 2019: 1748579, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31828090

RESUMO

PURPOSE: To investigate the pachymetry distribution of central cornea and morphologic changes in subclinical keratoconus with normal biomechanics and determine their potential benefit for the screening of very early keratoconus. METHODS: This retrospective comparative study was performed in 33 clinically unaffected eyes with normal topography and biomechanics from 33 keratoconus patients with very asymmetric ectasia (VAE-NTB; Corvis Biomechanical Index defined) and 70 truly normal eyes from 70 age-matched subjects. Corneal topographic, tomographic, and biomechanical metrics were measured using Pentacam and Corvis ST. The distance and pachymetry difference between the corneal thinnest point and the apex were defined as DTCP-Apex and DPTCP-Apex, respectively, to evaluate the pachymetry distribution within the central cornea. The discriminatory power of metrics was analysed via the receiver operating characteristic curve. A logistic regression analysis was used to establish predictive models. RESULTS: The parameters, DTCP-Apex and DPTCP-Apex, were significantly higher in VAE-NTB than those in normal eyes. For differentiating normal and VAE-NTB eyes, the Belin-Ambrósio deviation (BAD-D) showed the largest area under the curve (AUC; 0.799), followed by ARTmax (0.798), DTCP-Apex (0.771), tomography and biomechanical index (0.760), maximum pachymetry progression index (PPImax, 0.756), DPTCP-Apex (0.753), and back eccentricity (B_Ecc, 0.707) with no statistically significant differences among these AUCs. In the VAE-NTB group, the parameter B_Ecc was significantly and positively correlated with DTCP-Apex (P=0.011) and DPTCP-Apex (P=0.035), whereas the posterior elevation difference had a significant positive association with DPTCP-Apex (P=0.042). A model using the indices DTCP-Apex, B_Ecc, PPImax, and index of height asymmetry demonstrated the highest AUC of 0.846 with 91.43% specificity. CONCLUSIONS: Abnormal pachymetry distribution within the central cornea and subtle morphologic changes are detectable in subclinical keratoconus with normal biomechanics. This may improve VAE-NTB eyes detection.


Assuntos
Córnea/patologia , Ceratocone/patologia , Adulto , Área Sob a Curva , Paquimetria Corneana/métodos , Topografia da Córnea/métodos , Feminino , Humanos , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia/métodos , Adulto Jovem
6.
Thorac Cancer ; 10(4): 587-592, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30779329

RESUMO

BACKGROUND: Immunotherapy has considerably changed the treatment of lung cancer. As immunotherapy has a special mechanism of action, the disease remission that it can induce is unique. Recently, Immune Response Evaluation Criteria in Solid Tumors (iRECIST), which focus on assessing the apparent curative effect of immunotherapy, have become widely accepted. Based on iRECIST criteria, if the response to immunotherapy is determined to be immunity-confirmed progressive disease or immunity-unconfirmed progressive disease, and the Eastern Cooperative Oncology Group score is worse than before treatment, immunotherapy should be discontinued. We report two immunity-confirmed progressive disease cases after pembrolizumab treatment and one immunity-unconfirmed progressive disease case after nivolumab treatment. All three patients benefited from continued immunotherapy, which indicates that the iRECIST criteria may have limitations in assessing the efficacy of immunotherapy for non-small cell lung cancer patients.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe/administração & dosagem , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/imunologia , Progressão da Doença , Feminino , Humanos , Imunoterapia , Neoplasias Pulmonares/imunologia , Masculino , Pessoa de Meia-Idade , Nivolumabe/uso terapêutico , Critérios de Avaliação de Resposta em Tumores Sólidos , Resultado do Tratamento
7.
J Environ Manage ; 161: 408-416, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26210774

RESUMO

Export tax rebates are an important policy instrument for stimulating exports, which many developing countries make use of. However, excessive export tax rebates and inappropriate structural arrangements can lead to over-production in highly polluting industries and cause the environment to deteriorate. This paper, taking China as the study case, tests and verifies the statistical significance of the causal relationship between export tax rebates and pollution emissions. With a computable general equilibrium modeling, the current study further analyzes the effectiveness of export tax rebate adjustments aimed at alleviating environmental pressure for different time periods. It is found that before 2003, export tax rebates primarily promoted exports and boosted foreign exchange reserves, and highly polluting sectors enjoyed above-average export tax rebates, which led to increased pollution emissions. Between 2003 and 2010, the export tax rebate system was reformed to reduce support for the highly polluting export sectors, which led to decreases in emissions. Canceling export tax rebates for highly polluting sectors is shown to be the most favorable policy choice for improving the environmental performance of China's international trade. This study can serve as reference for other developing countries which similarly rely on export tax rebates, so that they can adjust their policies so as to combine economic growth with pollution control.


Assuntos
Comércio/métodos , Poluição Ambiental/economia , Poluição Ambiental/prevenção & controle , Impostos/economia , Poluição do Ar/análise , China , Desenvolvimento Econômico , Meio Ambiente , Indústrias/economia , Modelos Econômicos
8.
Ying Yong Sheng Tai Xue Bao ; 18(10): 2367-73, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-18163325

RESUMO

Ecological assets assessment is of great significance in building harmonious society and implementing scientific concept of development. Based on the achievements in ecological assets assessment research, the concept and scope of ecological assets were re-examined, and the contents of ecological assets assessment were summarized in this paper. It was considered that ecosystem quality, ecosystem pressure and ecological assets value should be the focus in assessing ecological assets. With the ecological assets assessment on forest ecosystem as an example, some referenced indicators and calculation models were given. By the end of the paper, some suggestions on the further study were presented.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecologia , Monitoramento Ambiental/métodos , China , Conservação dos Recursos Naturais/estatística & dados numéricos , Monitoramento Ambiental/estatística & dados numéricos
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