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1.
J Environ Manage ; 350: 119652, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38016235

RESUMO

Renewable energy (RE) plays a crucial role in global energy transformation, and a thorough study of the potential impact of RE on regional carbon emissions is of great significance. This is particularly relevant to China, which needs to clarify its path to carbon reduction. Using the sample data of 30 provinces in China from 2000 to 2021, this paper uses the Granger causality test to verify the causal relationship between carbon emission intensity (CEI) and other factors. It builds a mediation effect model on this basis to explore the direct impact effect and indirect transmission path of renewable energy utilization (REU) on CEI. The results show that REU has a one-way causal relationship with CEI. REU can directly and indirectly reduce CEI by improving social wealth and changing the direction of energy investment. In addition, REU indirectly increases CEI through the transmission paths of investment in the energy industry - social affluence and industrial level-social affluence. The CEI is indirectly reduced through the conduction paths of (social affluence-Urbanization rate), (Investment in the energy industry-Urbanization rate), (Industrial level-Urbanization rate), and (Industrial level-Investment in the energy industry). These conclusions will assist policymakers in exploring targeted pathways for low-carbon power development, providing a reference for strategic and sustainable carbon reduction policies.


Assuntos
Dióxido de Carbono , Carbono , Carbono/análise , Dióxido de Carbono/análise , Urbanização , Energia Renovável , China , Desenvolvimento Econômico
2.
Environ Sci Pollut Res Int ; 30(26): 68998-69023, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37127742

RESUMO

As an industry with immense decarbonization potential, the low-carbon transformation of the power sector is crucial to China's carbon emission (CE) reduction commitment. Based on panel data of 30 provinces in China from 2000 to 2019, this research calculates and analyzes the provincial CE intensity in electricity generation (CEIE) and its spatial distribution characteristics. Additionally, the GTWR model based on the construction explains the regional heterogeneity and dynamic development trend of each driving factor's influence on CEIE from time and space. The main results are as follows: CEIE showed a gradual downward trend in time and a spatial distribution pattern of high in the northeast and low in the southwest. The contribution of driving factors to CEIE has regional differences, and the power structure contributes most to the CEIE of the power sector, which promotes regional CE. Concurrently, most provinces with similar economic development, technological level, geographic location, or resource endowment characteristics show similar spatial and temporal trends. These detections will furnish broader insights into implementing CE reduction policies for the regional power sector.


Assuntos
Dióxido de Carbono , Carbono , Carbono/análise , Dióxido de Carbono/análise , Eletricidade , China , Desenvolvimento Econômico
3.
Environ Sci Pollut Res Int ; 30(12): 35034-35053, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36522575

RESUMO

Carbon emission (CE) reduction has become the primary task of China's urban agglomerations (UAs) in achieving sustainable development goals. This paper uses a decoupling model and coupling coordination model to measure the relationship between the development levels of different types of UAs and CEs in China from 2004 to 2016. Concurrently, the geographically and temporally weighted regression model is used to explore the spatial heterogeneity of the impact of different driving factors on the CEs of UAs. The results show the following: Most UAs have the potential to further decouple CEs and economic growth. Most UAs are still in coordinated development (> 0.5). Among the service innovation UAs, the Yangtze River Delta UA has a coupling coordination of less than 0.3, while the Pearl River Delta UA has a coupling coordination of more than 0.8, showing polarization. Manufacturing and resource-based UAs are still in the grinding adaptation stage (0.5-0.8). There are apparent spatiotemporal differences in the impacts of various driving factors on the CE of UAs. The level of land urbanization and investment in fixed assets promote CEs. However, the level of population urbanization and industrial structure restrain CEs. Therefore, reducing land development and industrial transformation can be an effective means to reduce CEs in UAs. These findings will provide extensive insights for different UAs to achieve differentiated low-carbon development.


Assuntos
Carbono , Urbanização , China , Desenvolvimento Sustentável , Indústrias , Rios , Desenvolvimento Econômico , Cidades
4.
Artigo em Inglês | MEDLINE | ID: mdl-34299805

RESUMO

Over the past decades, both the quantity and quality of food supply for millions of people have improved substantially in the course of economic growth across the developing world. However, the number of undernourished people has resumed growth in the 2010s amid food supply disruptions, economic slowdowns, and protectionist restrictions to agricultural trade. Having been common to most nations, these challenges to the food security status of the population still vary depending on the level of economic development and national income of individual countries. In order to explore the long-run determinants of food supply transformations, this study employs five-stage multiple regression analysis to identify the strengths and directions of effects of agricultural production parameters, income level, price indices, food trade, and currency exchange on supply of calories, proteins, and fats across 11 groups of agricultural products in 1980-2018. To address the diversity of effects across developing nations, the study includes 99 countries of Asia, Europe, Latin America, the Middle East, and Africa categorized as low-income, lower-middle-income, and upper-middle-income economies. It is found that in low-income countries, food supply parameters are more strongly affected by production factors compared to economic and trade variables. The effect of economic factors on the food supply of higher-value food products, such as meat and dairy products, fruit, and vegetables, increases with the rise in the level of income, but it stays marginal for staples in all three groups of countries. The influence of trade factors on food supply is stronger compared to production and economic parameters in import-dependent economies irrelevant of the gross national income per capita. The approach presented in this paper contributes to the research on how food supply patterns and their determinants evolve in the course of economic transformations in low-income countries.


Assuntos
Países em Desenvolvimento , Abastecimento de Alimentos , Economia , Humanos , Pobreza , Estudos Retrospectivos , Verduras
5.
Environ Sci Pollut Res Int ; 28(45): 64220-64233, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34302246

RESUMO

Detailed analysis the disparity and reduction potential of clinker emission factors at the provincial level is important for regional reduction policies. Using the surveyed data from 185 new suspension and pre-heater (NSP) process lines and 69 shaft kiln lines, this study firstly analyzed the disparity in emission factors based on production process, production scale, and regional distribution in 2015. We found that the emission factor of the shaft kiln process (898.24 kg/t) is higher than that of the NSP process (858.59 kg/t), and that small-scale production lines have higher emission factors than large-scale lines both for the two process. China's clinker emission factors increase from the eastern to the western regions. Then, we estimated the reduction potential of structural adjustment, raw material substitution, and energy saving and fuel substitution in regional emission factors by 2030. The result shows that emission factors of the surveyed provinces will decrease by 101.41-174.60 kg/t compared to the values in 2015, which mainly contributes by energy saving and fuel substitution (65.98%), and raw material substitution (25.72%). And structural adjustment contributes only a small part reduction for most investigated provinces. The national average emission factor is estimated to be 715.33 kg/t in 2030, which indicates a reduction of 16.65%. These results can provide valuable feedback to government officials on the effectiveness of existing measures and also serve as a reference for future decisions on emission reduction polices.


Assuntos
Poluição do Ar , Monitoramento Ambiental , Poluição do Ar/análise , China
6.
Artigo em Inglês | MEDLINE | ID: mdl-32785155

RESUMO

The stability of food supply chains is crucial to the food security of people around the world. Since the beginning of 2020, this stability has been undergoing one of the most vigorous pressure tests ever due to the COVID-19 outbreak. From a mere health issue, the pandemic has turned into an economic threat to food security globally in the forms of lockdowns, economic decline, food trade restrictions, and rising food inflation. It is safe to assume that the novel health crisis has badly struck the least developed and developing economies, where people are particularly vulnerable to hunger and malnutrition. However, due to the recency of the COVID-19 problem, the impacts of macroeconomic fluctuations on food insecurity have remained scantily explored. In this study, the authors attempted to bridge this gap by revealing interactions between the food security status of people and the dynamics of COVID-19 cases, food trade, food inflation, and currency volatilities. The study was performed in the cases of 45 developing economies distributed to three groups by the level of income. The consecutive application of the autoregressive distributed lag method, Yamamoto's causality test, and variance decomposition analysis allowed the authors to find the food insecurity effects of COVID-19 to be more perceptible in upper-middle-income economies than in the least developed countries. In the latter, food security risks attributed to the emergence of the health crisis were mainly related to economic access to adequate food supply (food inflation), whereas in higher-income developing economies, availability-sided food security risks (food trade restrictions and currency depreciation) were more prevalent. The approach presented in this paper contributes to the establishment of a methodology framework that may equip decision-makers with up-to-date estimations of health crisis effects on economic parameters of food availability and access to staples in food-insecure communities.


Assuntos
Infecções por Coronavirus/epidemiologia , Países Desenvolvidos/estatística & dados numéricos , Países em Desenvolvimento/estatística & dados numéricos , Abastecimento de Alimentos/economia , Abastecimento de Alimentos/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Betacoronavirus , COVID-19 , Alimentos/economia , Humanos , Fome , Renda , Pandemias , Prevalência , SARS-CoV-2
7.
Urol Oncol ; 33(4): 164.e19-23, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25665510

RESUMO

BACKGROUND: Patients with locally advanced prostate cancer (PCa) have worse outcomes after radical prostatectomy (RP) than patients with more favorable parameters. We conducted a phase II study of neoadjuvant chemotherapy with docetaxel before RP during 2000 to 2003 in patients with locally advanced disease. We report an updated long-term survival analysis of these patients. MATERIAL AND METHODS: Overall, 28 patients with locally advanced PCa (defined as serum preoperative [initial] prostate-specific antigen level ≥ 15 ng/ml, clinical ≥ T2b disease, or biopsy Gleason score ≥ 8) and no evidence of metastatic disease received 6 weekly doses of intravenous docetaxel (40 mg/m(2)) followed by RP. Disease status was assessed by shared medical records or followed by phone and fax. Biochemical recurrence (BCR) was defined as 2 consecutive prostate-specific antigen level readings ≥ 0.2 ng/ml. A Social Security Death Index search was conducted on all patients to ascertain date of death if unavailable in records. RESULTS: In total, 28 patients completed chemotherapy and underwent RP. At a median follow-up of 130 months (range: 37-166 mo), 10 patients (36%) remained alive and disease free clinically and biochemically with no additional therapy, whereas 18 patients (64%) had BCR. The estimated 10-year BCR-free survival is 33.5%, metastasis-free survival is 68.7%, PCa-specific survival is 92.2%, and overall survival is 79.7%. CONCLUSIONS: The use of neoadjuvant docetaxel chemotherapy in patients with locally advanced PCa undergoing RP remains undefined. Results from this study are informative but only hypothesis generating given the study was not powered for survival. Mature data from the ongoing CALGB 90203 and GETUG-12 studies will shed light on this clinical question.


Assuntos
Antineoplásicos/administração & dosagem , Prostatectomia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/cirurgia , Taxoides/administração & dosagem , Idoso , Quimioterapia Adjuvante , Terapia Combinada , Docetaxel , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/mortalidade , Modelos de Riscos Proporcionais , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/mortalidade , Resultado do Tratamento
8.
J Urol ; 191(4): 1066-71, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24161997

RESUMO

PURPOSE: We developed a model to optimize genetic testing in infertile men with nonobstructive azoospermia and severe oligospermia. We also assessed the optimal cutoff value of the predicted probability of advising genetic testing and evaluated the direct cost saving of using the model. MATERIALS AND METHODS: We retrospectively reviewed the records of infertile men who underwent Y microdeletion and karyotype testing at our fertility center from 2006 to 2012. Semen parameters, testicular volume, testosterone, luteinizing hormone, follicular stimulating hormone and varicocele were assessed as potential predictors of genetic disorders. We fitted logistic regression to all predictors and selected a nomogram based on the concordance index and calibration. We calculated the cost saving of using the model. RESULTS: Of 325 patients 278 fulfilled study inclusion criteria, including 27 with an abnormal karyotype, 11 with a Y microdeletion and 1 with each condition. We developed a nomogram using sperm concentration and motility, testicular volume and serum testosterone level. The nomogram concordance index was 0.738. The optimal cutoff value was 13.8% with 0.788 sensitivity, 0.590 specificity, 0.245 positive predictive value and 0.943 negative predictive value. Testing men above the 13.8% cutoff resulted in a direct 45% cost saving. However, 15.4% of genetic anomalies were missed, including 2 Y microdeletions. CONCLUSIONS: Using common clinical and laboratory parameters our nomogram detects 84.6% of genetic anomalies. Nomogram use resulted in a 45% direct cost saving but carries the risk of missing pertinent genetic abnormalities.


Assuntos
Testes Genéticos/economia , Testes Genéticos/normas , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/economia , Adulto , Algoritmos , Efeitos Psicossociais da Doença , Humanos , Infertilidade Masculina/genética , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos
9.
J Urol ; 183(2): 560-4, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20018314

RESUMO

PURPOSE: While many primary care providers advocate routine screening urinalyses, a heme positive dipstick test often leads to a false-positive diagnosis of hematuria, or pseudohematuria. Thus, American Urological Association guidelines recommend urological evaluation for asymptomatic patients only for at least 3 red blood cells per high power field in 2 of 3 microscopic urinalyses. We determined the percentage of patients referred for asymptomatic hematuria undergoing unnecessary consultation and studies. MATERIALS AND METHODS: Patients were retrospectively identified if seen for initial consultation associated with CPT 599.7X, hematuria. Among these patients those referred for evaluation of asymptomatic nonmacroscopic hematuria were identified, and referral patterns, ancillary tests, procedures and findings were examined. RESULTS: Of 320 new patient visits with diagnosis code 599.7X, 91 were referred for asymptomatic, nonmacroscopic hematuria. Of these patients only 37 (41%) had microscopic urinalyses before referral and only 22 (24%) had microscopic urinalyses showing 3 or more red blood cells per high power field. Of the 69 patients referred without confirmed microhematuria approximately 25% had true microhematuria and 15 with no true hematuria had undergone imaging before referral. The Medicare reimbursement value for the evaluation of these 69 patients was $44,901. Of these patients 35 underwent cystoscopy and only 1 (with true microhematuria) had a malignancy. CONCLUSIONS: Positive dipstick heme tests should always be confirmed by microscopic urinalysis before urological referral or evaluation. Education of referring physicians regarding the American Urological Association guidelines could possibly help limit costly and potentially harmful, unnecessary evaluation of patients without true microhematuria.


Assuntos
Hematúria/diagnóstico , Hematúria/urina , Encaminhamento e Consulta/estatística & dados numéricos , Procedimentos Desnecessários/estatística & dados numéricos , Custos e Análise de Custo , Hematúria/epidemiologia , Humanos , Procedimentos Desnecessários/economia , Urinálise/economia , Urinálise/normas , Urinálise/estatística & dados numéricos
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