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1.
J Environ Manage ; 347: 119066, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37801943

RESUMO

Quantity-based and concentration-based limits are two common environmental permitting approaches utilized by government worldwide in environmental management. While existing literature is still unambiguous about roles played by quantity-based versus concentration-based limits in environmental management, it becomes evident that relying exclusively on concentration-based or quantity-based limits to control plant emissions may not necessarily result in improved environmental quality. This paper leverages a unique opportunity arising from a recent reform in China's Pollutant Emission Permit System (PEPS) initiated in 2016 to analyze how the introduction of quantity-based limits in addition to concentration-based limits through the PEPS reform impact emissions at the plant level. Utilizing a unique plant-level continuous emission monitoring system data collected from Shaanxi Province (located in western China), the paper finds a significant reduction in air pollutant emissions as a result of the PEPS reform (nitrogen oxides (NOx) by 39%, sulfur dioxide (SO2) by 15% and particulate matter (PM) by 13%). The heterogeneity analyses show emission reductions in plants differ across those with varying quantity limits specified in their permits, distinct emission ratios and diverse ownership structures. Furthermore, plants that fall under the classified management system with more stringent regulations imposed, especially those operating in high-pollution sectors, situated within industrial parks, or classified as large-sized plants, attain higher pollutant quantity limits. Findings of the paper carry important implications for effective environmental management, particularly within developing countries, and shed some light on carbon emission reduction policies in China.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Poluição do Ar/análise , Poluentes Ambientais/análise , Monitoramento Ambiental , Poluentes Atmosféricos/análise , Material Particulado/análise , China
2.
Sci Rep ; 13(1): 933, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650226

RESUMO

Aiming at the problem of large deformation and difficulty in surrounding rock control of the top coal roadway in thick seam, theoretical analysis, theoretical analysis, numerical simulation, orthogonal matrix analysis and other methods were used to study the roof deformation and support parameter optimization of the top coal roadway in thick seam. Firstly, the structural model and roof mechanical model of the top coal roadway in thick seam were established, and the deformation coefficient TK was defined based on the relationship between curvature radius and bending moment, maximum bending moment and ultimate tensile strength of beam. According to the ratio of deformation rate between TK and beam to determine the roof deformation mode of top coal roadway, the discriminant conditions of roadway roof stability under two deformation conditions are obtained. Due to the characteristics of serious coal-rock fragmentation, large roof deformation, and integration of top coal and side coal. Therefore, the combined support method of "high prestressed long and short anchor cables" is proposed by double arch bearing structure control technology. Finally, based on the orthogonal matrix analysis method of supporting parameters optimization of the top coal roadway in thick seam, the analysis amount of supporting scheme is significantly reduced, the comprehensive evaluation of multi-factor and multi-supporting effect of roadway support is realized, and the optimal supporting scheme is obtained. Compared with the surrounding rock of the roadway without support, the deformation of the roof is reduced by 27.27%, the deformation of the two sides is reduced by 45.24%, and the tensile failure volume is reduced by 54.66%. The top coal roadway in thick seam has been effectively controlled, which provides guarantee for high yield and high efficiency of the mine.

3.
Front Public Health ; 10: 1056720, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466506

RESUMO

Objective: We explored the feasibility of app-based HIV testing services (AHTS) among men who have sex with men (MSM) according to the perspectives of testing service providers. Methods: Twenty-one current or previous AHTS providers participated in a semi-structured interview which explored the facilitators and barriers to AHTS. Ten participants originating from the Center for Disease Control and Prevention (CDC) and 11 from the non-governmental organization (NGO) in Shijiazhuang, China took part in this study. Interviews was transcribed verbatim, and the socioecological model (SEM) was applied to thematic analysis. Results: Twenty-one participants from AHTS services commented on the integration of online appointment schedules into HIV testing services. AHTS was deemed a convenient and efficient method for MSM and service providers to choose their preferred location and times. Moreover, it allowed for important HIV-related information to be accessed online and targeted toward at-risk individuals. Participants thought MSM may feel unsure about personal information security being stored within a privatized app and was considered a barrier to AHTS's usability. As such, they believed establishing a government-led national online platform for AHTS would allow for greater trust from MSM, rather than a social media app. Conclusion: By linking booking services to an online platform, AHTS was deemed a convenient and efficient method for HIV testing services, especially for young MSM who are familiar with smartphone applications. To improve the use of these services, AHTS apps should focus on ensuring the confidentiality of personal information and internet security to build trust between MSM and service providers.


Assuntos
Aplicativos Móveis , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Teste de HIV , Rede Social , Pesquisa Qualitativa , China
4.
ACS Omega ; 7(50): 46682-46692, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36570312

RESUMO

Aiming at the problems of large deformation and difficult control of the mining roadway water drenching in a thick coal seam, the principle of double-arch zoning cooperative surrounding rock control is studied by using the combined method of theoretical analysis, numerical simulation, and industrial experiment. The water-rock interaction of the surrounding rock of water-drenching roadway is proposed, taking into account the damage to the mechanical parameters of the surrounding rock caused by soaking water. The water-mechanical-damage coupling model for surrounding rock of a coal seam roadway is constructed, and is numerically solved by the code development using the FISH language. The principle of "high prestressed bolt-cable-mesh" zone coordinated control is revealed, and the existence of a compressive stress arch is verified by FLAC3D software. The three support schemes were compared and analyzed by numerical simulation software. We affirmed the bolt length of 2400 mm, spacing of 0.9 m, row spacing of 1 m, cable length of 7300 mm, and arrangement 3-2-3 as the optimal support scheme and applied this scheme in the Zhangcun Coal Mine. The results show that the maximum deformation of the roadway roof is 142 mm, and the ultimate convergence of the two sides is 83 mm. The surrounding rock has been effectively controlled.

5.
Sci Rep ; 12(1): 20017, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36414697

RESUMO

Deformation and failure of the roadway surrounding rock under dynamic disturbance were explored, which is essential for the control of the surrounding rock. The impact of dynamic disturbance on the deformation and failure of the roadway surrounding rock was studied from a single factor perspective using numerical simulation software. The disturbance intensity, frequency, and time were determined to affect the deformation and plastic zone of the surrounding rock. Firstly, a multi-factor integrated study was achieved using an orthogonal experimental design, and the impact of the three factors on the deformation and plastic zone of the surrounding rock were studied by applying mean value and extreme difference. The results show that the degree of influence of deformation of the roof is time > intensity > frequency in order. The impact of the plastic zone volume is intensity > frequency > time in order. Finally, a multivariate regression model was established using multiple regression analysis. The P = 0 < 0.05 for the regression model is obtained by variance analysis, and the equation regression is significant, which can effectively predict the deformation and failure of the surrounding rock under dynamic disturbance.


Assuntos
Plásticos , Simulação por Computador
6.
Stem Cell Res Ther ; 13(1): 449, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064647

RESUMO

BACKGROUND: Increasing studies have reported the therapeutic effect of mesenchymal stem cell (MSC)-derived exosomes by which protein and miRNA are clearly characterized. However, the proteomics and miRNA profiles of exosomes derived from human embryonic stem cells (hESCs) and human-induced pluripotent stem cells (hiPSCs) remain unclear. METHODS: In this study, we isolated exosomes from hESCs, hiPSCs, and human umbilical cord mesenchymal stem cells (hUC-MSCs) via classic ultracentrifugation and a 0.22-µm filter, followed by the conservative identification. Tandem mass tag labeling and label-free relative peptide quantification together defined their proteomics. High-throughput sequencing was performed to determine miRNA profiles. Then, we conducted a bioinformatics analysis to identify the dominant biological processes and pathways modulated by exosome cargos. Finally, the western blot and RT-qPCR were performed to detect the actual loads of proteins and miRNAs in three types of exosomes. RESULTS: Based on our study, the cargos from three types of exosomes contribute to sophisticated biological processes. In comparison, hESC exosomes (hESC-Exos) were superior in regulating development, metabolism, and anti-aging, and hiPSC exosomes (hiPSC-Exos) had similar biological functions as hESC-Exos, whereas hUC-MSCs exosomes (hUC-MSC-Exos) contributed more to immune regulation. CONCLUSIONS: The data presented in our study help define the protein and miRNA landscapes of three exosomes, predict their biological functions via systematic and comprehensive network analysis at the system level, and reveal their respective potential applications in different fields so as to optimize exosome selection in preclinical and clinical trials.


Assuntos
Exossomos , Células-Tronco Pluripotentes Induzidas , Células-Tronco Mesenquimais , MicroRNAs , Exossomos/genética , Exossomos/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteômica , Cordão Umbilical
7.
Sci Total Environ ; 826: 154065, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35217038

RESUMO

Clean heating (CH) is regard as a key strategy to address the serious air pollution problem in northern China. A "one-fit-all" CH strategy will harm social welfare and engender resistance, due to the differences in heating habits and residents' income between urban and rural areas. To solve this problem, a 5 km × 5 km gridded cost-benefit analysis model for CH is build. Taking the case city as an example, an improved CH solution integrating multiple heat sources is proposed. By utilizing ISH resources, which are low-cost and low-emission-intensity, the improved solution reduces heating-induced PM2.5 emissions to one-fifth, and achieves higher net social benefits than existing CH strategies. Moreover, the spatial distributions of PM2.5 emission reductions and indoor and outdoor health benefits induced by CH strategy, including coal-to-gas/electricity and the improved strategy we propose, are simulated; revealing that the spillover effects of pollutants make CH will somewhat inevitably bring about a transfer of social welfare from rural areas to urban areas, but this can be compensated by opposite direction subsidies.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , China , Análise Custo-Benefício , Monitoramento Ambiental , Calefação , Material Particulado/análise , Seguridade Social
8.
BMC Med Ethics ; 22(1): 14, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588803

RESUMO

BACKGROUND: Artificial intelligence (AI) has been described as the "fourth industrial revolution" with transformative and global implications, including in healthcare, public health, and global health. AI approaches hold promise for improving health systems worldwide, as well as individual and population health outcomes. While AI may have potential for advancing health equity within and between countries, we must consider the ethical implications of its deployment in order to mitigate its potential harms, particularly for the most vulnerable. This scoping review addresses the following question: What ethical issues have been identified in relation to AI in the field of health, including from a global health perspective? METHODS: Eight electronic databases were searched for peer reviewed and grey literature published before April 2018 using the concepts of health, ethics, and AI, and their related terms. Records were independently screened by two reviewers and were included if they reported on AI in relation to health and ethics and were written in the English language. Data was charted on a piloted data charting form, and a descriptive and thematic analysis was performed. RESULTS: Upon reviewing 12,722 articles, 103 met the predetermined inclusion criteria. The literature was primarily focused on the ethics of AI in health care, particularly on carer robots, diagnostics, and precision medicine, but was largely silent on ethics of AI in public and population health. The literature highlighted a number of common ethical concerns related to privacy, trust, accountability and responsibility, and bias. Largely missing from the literature was the ethics of AI in global health, particularly in the context of low- and middle-income countries (LMICs). CONCLUSIONS: The ethical issues surrounding AI in the field of health are both vast and complex. While AI holds the potential to improve health and health systems, our analysis suggests that its introduction should be approached with cautious optimism. The dearth of literature on the ethics of AI within LMICs, as well as in public health, also points to a critical need for further research into the ethical implications of AI within both global and public health, to ensure that its development and implementation is ethical for everyone, everywhere.


Assuntos
Inteligência Artificial , Atenção à Saúde , Cuidadores , Humanos , Princípios Morais , Pobreza
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