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1.
J Environ Manage ; 368: 122273, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39191058

RESUMO

Carbon emissions trading scheme (ETS) will change the internal and external operating environment of related companies, increase new carbon reduction costs, and may affect their investment behavior and decision-making. This study constructs the policy effect evaluation model to evaluate the net effect of China's ETS pilot policy on the investment efficiency of related companies in high-carbon industries. This study indicates that: first, China's ETS pilot policy has reduced the inefficient investment of related companies by 11.40% during the sample period. Second, innovation ability plays an enhanced moderating effect in the inhibitory effect of China's ETS pilot policy on the inefficient investment of related companies in the short term, but the effect is weakened in the long-term. Third, the policy effect is relatively obvious for non-state-owned companies and companies with more institutional shareholdings. This research has important reference value for the continuous improvement of China's national carbon market, and the steady transformation from simple investment-driven to investment-efficiency-driven economic development in China.


Assuntos
Carbono , Investimentos em Saúde , China , Desenvolvimento Econômico , Poluição do Ar/prevenção & controle
2.
J Environ Manage ; 356: 120635, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508001

RESUMO

The transport sector proves a major energy consumer in China, but improving energy-saving performance in China's provincial transport sector from the lifecycle perspective remains unresolved. Thus, this study employs the environmentally extended multi-region input-output (MRIO) method, structural path analysis, and the newest MRIO table of China from 2017, to investigate how to improve the energy-saving performance from final demand structure, supply chain, and pathway perspectives. The relevant results are threefold. (1) Regarding the final demand structure level, the embodied energy consumption of China's transport sector is predominantly driven by investment from the production side, while that of the consumption side is primarily caused by exports. (2) At the supply chain level, production-side embodied energy consumption primarily occurs along a three-echelon supply chain, while that from the consumption side mostly occurs via a two-echelon supply chain. (3) At the pathway level, the production-side energy-saving performance of China's provincial transport sector is dominated by two pathways along the construction sector, including transport sector → construction sector → final demands, and transport sector → intermediate inputs → construction sector → final demands, while that of the consumption side is chiefly determined by three pathways along internal transportation chains.


Assuntos
Desenvolvimento Econômico , Investimentos em Saúde , China , Meios de Transporte , Dióxido de Carbono/análise
3.
Environ Sci Technol ; 55(10): 6631-6643, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33961411

RESUMO

China today has an urgent need to develop low-carbon policies that also address local air pollution. This study uses a difference-in-differences model to estimate the extent to which China's Emissions Trading Scheme (ETS), which directly addresses CO2 emissions, has also generated cobenefits by reducing PM2.5. Using monthly PM2.5 concentration and weather data for 297 Chinese cities from January 2005 to December 2017, we find that (1) China's ETS has reduced PM2.5 concentrations by 4.8%, and this reduction effect is strongest in summer. The results are confirmed by robustness tests including propensity score matching, mahalanobis distance matching, two placebo tests, and controlling atmospheric policies. (2) The ETS pilots have positive spillovers on neighboring nonpilot cities within 300 km of the pilot cites, especially for those downwind neighboring nonpilot cities, and the ETS's cobenefits are primarily a result of firms adopting abatement activities and adjusting industrial structure. (3) The cobenefits of China's ETS pilots are greater in regions with larger carbon trading volume and higher carbon trading price. (4) The reduction in PM2.5 concentration caused by China's ETS may have avoided 23,363 deaths and saved $41.38 billion annually in GDP.


Assuntos
Poluição do Ar , Carbono , Poluição do Ar/prevenção & controle , Carbono/análise , China , Cidades , Indústrias , Material Particulado
4.
Eval Program Plann ; 107: 102481, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39182393

RESUMO

Curriculum is the core element of talent cultivation in universities, and its quality directly determines that of the talent cultivation. However, the efficiency of online course resource allocation in universities of China is unacceptable, and the corresponding driving mechanisms are unclear. Based on the data of iCourses platform for a top university (H University) of China, this paper develops the DEA-Malmquist index and Tobit regression model to evaluate the efficiency of university online course resource allocation and explore its main influencing factors. The empirical results indicate that, first of all, humanities and social sciences outperform natural sciences in the resource allocation efficiency of online courses. Compared with non-national premium online courses, the resource investment redundancy of national premium online courses appears relatively lower. Secondly, from the perspective of temporal changes, the total factor productivity of online course resource allocation generally has a downward trend. The innovation effect of technological progress is more significant, while the catch-up effect of technical efficiency is clearly insufficient. Scale efficiency is the main factor hindering its improvement. Finally, in terms of the factors affecting the efficiency of online course resource allocation, teachers' research guidance capability, teaching research skills, and the number of courses offered have significantly positive impact.


Assuntos
Avaliação de Programas e Projetos de Saúde , Alocação de Recursos , China , Humanos , Universidades/organização & administração , Educação a Distância/organização & administração , Currículo , Internet , Ciências Humanas/educação , Ciências Sociais/educação , Disciplinas das Ciências Naturais/educação
5.
J Glob Antimicrob Resist ; 36: 36-40, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38072241

RESUMO

OBJECTIVES: Aquatic ecosystems serve as a dissemination pathway and a reservoir of both antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). This study aimed to determine the prevalence of colistin-resistant mcr-like genes in Enterobacteriales in aquatic products, which may be contribute to the transfer of ARGs in water environments. METHODS: The mcr-1-positive Escherichia coli were recovered from 123 freshwater fish and 34 cultured crocodile cecum samples from 10 farmers' markets in Guangdong, China. Minimum inhibitory concentration (MIC) was determined using the agar dilution method. Genotyping was performed using pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). Conjugation assay was carried out to investigate the transferability of mcr-1. Genomic information was obtained by whole genome sequencing (WGS) and bioinformatic analysis. RESULTS: Forty-four mcr-1 positive isolates showed co-resistance to tetracycline, trimethoprim/sulfamethoxazole, and gentamicin, while they were all sensitive to tigecycline, meropenem, and amikacin. They were typed into sixteen PFGE clusters. ST10 and ST117 were the most popular sequence types, followed by ST1114. S1-PFGE verified the presence of the mcr-1 gene on plasmids in sizes of ∼60 kb (n = 1) and ∼240 kb (n = 3). Whole genome sequencing-based analysis identified mcr-1 integrated in IncHI2 plasmid (n = 3), IncI2 plasmid (n = 2), and bacterial chromosome in two copies (n = 1). In addition to mcr-1, they carried several other antibiotic resistance genes, such as blaCTX-M-14, fosA3, and aac(6')-Ib-cr. CONCLUSION: These data suggest that aquatic products are an important antibiotic resistance reservoir and highlight possible risks regarding food safety.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Animais , Tipagem de Sequências Multilocus , Proteínas de Escherichia coli/genética , Antagonistas de Receptores de Angiotensina , Ecossistema , Inibidores da Enzima Conversora de Angiotensina , Antibacterianos/farmacologia
6.
Virulence ; 15(1): 2356692, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38797966

RESUMO

The increasing antibiotic resistance poses a significant global health challenge, threatening our ability to combat infectious diseases. The phenomenon of collateral sensitivity, whereby resistance to one antibiotic is accompanied by increased sensitivity to another, offers potential avenues for novel therapeutic interventions against infections unresponsive to classical treatments. In this study, we elucidate the emergence of tobramycin (TOB)-resistant small colony variants (SCVs) due to mutations in the hemL gene, which render S. Typhimurium more susceptible to nitrofurantoin (NIT). Mechanistic studies demonstrate that the collateral sensitivity in TOB-resistant S. Typhimurium SCVs primarily stems from disruptions in haem biosynthesis. This leads to dysfunction in the electron transport chain (ETC) and redox imbalance, ultimately inducing lethal accumulation of reactive oxygen species (ROS). Additionally, the upregulation of nfsA/B expressions facilitates the conversion of NIT prodrug into its active form, promoting ROS-mediated bacterial killing and contributing to this collateral sensitivity pattern. Importantly, alternative NIT therapy demonstrates a significant reduction of bacterial load by more than 2.24-log10 cfu/g in the murine thigh infection and colitis models. Our findings corroborate the collateral sensitivity of S. Typhimurium to nitrofurans as a consequence of evolving resistance to aminoglycosides. This provides a promising approach for treating infections due to aminoglycoside-resistant strains.


Assuntos
Antibacterianos , Nitrofurantoína , Salmonella typhimurium , Tobramicina , Nitrofurantoína/farmacologia , Animais , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Tobramicina/farmacologia , Camundongos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana/genética , Mutação , Feminino , Espécies Reativas de Oxigênio/metabolismo , Infecções por Salmonella/microbiologia , Infecções por Salmonella/tratamento farmacológico , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
7.
Financ Innov ; 9(1): 75, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063169

RESUMO

Forecasting returns for the Artificial Intelligence and Robotics Index is of great significance for financial market stability, and the development of the artificial intelligence industry. To provide investors with a more reliable reference in terms of artificial intelligence index investment, this paper selects the NASDAQ CTA Artificial Intelligence and Robotics (AIRO) Index as the research target, and proposes innovative hybrid methods to forecast returns by considering its multiple structural characteristics. Specifically, this paper uses the ensemble empirical mode decomposition (EEMD) method and the modified iterative cumulative sum of squares (ICSS) algorithm to decompose the index returns and identify the structural breakpoints. Furthermore, it combines the least-square support vector machine approach with the particle swarm optimization method (PSO-LSSVM) and the generalized autoregressive conditional heteroskedasticity (GARCH) type models to construct innovative hybrid forecasting methods. On the one hand, the empirical results indicate that the AIRO index returns have complex structural characteristics, and present time-varying and nonlinear characteristics with high complexity and mutability; on the other hand, the newly proposed hybrid forecasting method (i.e., the EEMD-PSO-LSSVM-ICSS-GARCH models) which considers these complex structural characteristics, can yield the optimal forecasting performance for the AIRO index returns.

8.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): o2929, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22219960

RESUMO

In the title mol-ecule, C(16)H(13)NO, the indoline-2-one ring system is nearly planar [maximum atomic deviation = 0.082 (2) Å] and is oriented at a dihedral angle of 66.60 (12)° with respect to the phenyl ring. In the crystal, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into supra-molecular dimers.

9.
Environ Sci Pollut Res Int ; 26(31): 31632-31643, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31485948

RESUMO

In recent years, BRICS countries have attached great importance to renewable energy development and actively promoted the shift of economic structure towards service industry, in order to achieve the decoupling of economic development from carbon emissions. However, relevant studies mostly neglect the cross-sectional dependence and heterogeneity issues, which may cause biased results. Therefore, this paper selects the panel data of BRICS countries during 1996-2017 and employs the common correlated effects mean group (CCEMG) method, which are based on the cross-sectional dependence and heterogeneity assumptions, to explore the influence of renewable energy consumption and service industry development on CO2 emissions in BRICS countries. Besides, we also use the random effects model and pooled estimated generalized least squares model, as well as fully modified OLS model for comparison. The results indicate that enhancing the proportion of renewable energy consumption in the total energy consumption is an effective measure to reduce CO2 emissions in BRICS countries. Moreover, the steadily rising contribution of service industry to economic growth in BRICS countries during the sample period does not necessarily contribute to reduce CO2 emissions.


Assuntos
Dióxido de Carbono/química , Carbono/química , Energia Renovável/economia , Estudos Transversais , Desenvolvimento Econômico , Desenvolvimento Industrial , Análise dos Mínimos Quadrados
10.
RSC Adv ; 9(42): 24595-24602, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35527853

RESUMO

Memristors, which feature small sizes, fast speeds, low power, CMOS compatibility and nonvolatile modulation of device resistance, are promising candidates for next-generation data storage and in-memory computing paradigms. Compared to the binary logics enabled by memristor devices, ternary logics with larger information-carrying capacity can provide higher computation efficiency with simple operation schemes, reduced circuit complexity and smaller chip areas. In this study, we report the fabrication of memristor devices based on nano-columnar crystalline ZnO thin films; they show symmetric and reliable multi-level resistive switching characteristics over three hundred cycles, which benefits the implementation of univariate ternary logic operations. Experimental results demonstrate that a three-valued logic complete set can be realized by the univariate operations of the present ZnO memristor device, and a ternary multiplier unit circuit is designed for potential applications. The present methodology can be beneficial for constructing future high-performance computation architectures.

11.
Environ Sci Pollut Res Int ; 25(20): 20179-20192, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29748805

RESUMO

As economic integration in the world continues to advance, energy consumption and carbon emissions in various regions have also become increasingly interdependent. In order to better understand the regional interaction of carbon emissions, this paper employs a three-region input-output approach to explore the linkage of CO2 emissions among China, EU, and USA. Based on the world input-output table and environment account of World Input-Output Database (WIOD) in 2009, we calculate the carbon emission multiplier effect, spillover effect, and feedback effect and carry out the analysis from the regional and sectoral levels. The results show that, first of all, the carbon emission multiplier effect of each region is larger than the spillover and feedback effects. Second, EU and USA have higher carbon emission spillover effect on China than China's carbon emission spillover effect on them. Finally, the carbon multiplier effects in different sectors have different characteristics.


Assuntos
Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Carbono/análise , China , União Europeia , Gases de Efeito Estufa/análise , Estados Unidos
12.
Artigo em Inglês | MEDLINE | ID: mdl-30115833

RESUMO

Against the backgrounds of emission reduction targets promised by China, it is crucial to explore drivers of CO2 emissions comprehensively for policy making. In this study, Shandong Province in China is taken as an example to investigate drivers in carbon density by using an extended Kaya identity and a logarithmic mean Divisia index model (LMDI) with two layers. It is concluded that there are eight positive driving factors of carbon density during 2000⁻2015, including traffic congestion, land urbanization, etc., and seven negative driving factors comprising energy intensity, economic structure, etc. Among these factors, economic growth and energy intensity are the main positive and negative driving factor, respectively. The contribution rate of traffic congestion and land urbanization is gradually increasing. Meanwhile, 15 driving factors are divided into five categories. Economic effect and urbanization effect are the primary positive drivers. Contrarily, energy intensity effect, structural effect, and scale effect contribute negative effects to the changes in carbon density. In the four stages, the contribution of urbanization to carbon density is inverted U. Overall, the results and suggestions can give support to decision maker to draw up relevant government policy.


Assuntos
Poluição do Ar , Dióxido de Carbono , Modelos Teóricos , Urbanização , Carbono , China , Desenvolvimento Econômico
13.
Anim Sci J ; 88(8): 1232-1238, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28078817

RESUMO

The aim of this study was to evaluate fertility and sex ratios after artificial insemination in dogs under field conditions. Semen was cryopreserved as unsorted (control) or was separated into X- and Y-chromosome-bearing sperm using a cell sorter. Sixty female dogs were inseminated with frozen-thawed spermatozoa of 100 × 106 unsorted (a dose in practice) and 4 × 106 sorted (X and Y group, respectively). A total of 20 dogs became pregnant and 126 puppies were born from the three groups. The percentage of parturition was similar for the X (5/20; 25.0%) and Y (4/20; 20.0%) group (P > 0.05), but lower than controls (11/20; 55.0%) (P < 0.05). Ultimately 28 out of the 32 puppies produced from X group were female (87.5%) and 19/22 (86.4%) puppies of Y group were male. In contrast, sex ratio (51.4% to 48.6%) in the control was significantly different from the X, Y group (P < 0.05). However, male and female puppies in the control had similar birth weights and weaning weights to those from the X and Y groups. This preliminary information indicated that normal puppies of predicted sex can be produced with low numbers of sorted cryopreserved dog spermatozoa at a farm level, making sperm-sexing technology potentially applicable for elite breeding units.


Assuntos
Criopreservação , Fertilidade , Congelamento , Inseminação Artificial , Parto , Prenhez , Preservação do Sêmen , Pré-Seleção do Sexo/métodos , Razão de Masculinidade , Espermatozoides , Animais , Cães , Feminino , Masculino , Gravidez
14.
Materials (Basel) ; 9(7)2016 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-28773625

RESUMO

Using ammonium nitrate (AN) as a propellant oxidizer is limited due to its hygroscopicity. This review consolidated the available information of various issues pertaining to the coating methods of the surface modification of ammonium nitrate for reducing its hygroscopicity. Moreover this review summarizes the recent advances and issues involved in ammonium nitrate surface modification by physical, chemical and encapsulation coating methods to reduce the hygroscopicity. Furthermore, coating materials, process conditions, and the hygroscopicity test conditions are extensively discussed along, with summaries of the advantages and disadvantages of each coating method. Our findings indicated that the investigation and development of anti-hygroscopicity of AN, and the mechanisms of surface modification by coating urgently require further research in order to further reduce the hygroscopicity. Therefore, this review is useful to researchers concerned with the improvement of ammonium salts' anti-hygroscopicity.

15.
Huan Jing Ke Xue ; 30(4): 1023-8, 2009 Apr 15.
Artigo em Zh | MEDLINE | ID: mdl-19545000

RESUMO

The series of stable AS/PDM composite coagulants prepared by polydimethyldiallylammonium chloride (PDM) and aluminium sulphate (AS) were used to research the algae-removal effect to winter Taihu Lake raw water. The effects of dosage of composite coagulants, composite mass ratios (20:1-5:1) of AS and PDM, intrinsic viscosity values (0.55-3.99 dL/g) of PDM on algae-removal rates were studied through coagulation and algae-removal experiments. The feasibility of using composite coagulants to substitute prechlorination process was analysed. The results show that when residual turbidity of 2 NTU to water after coagulation and sediment is required by water plant, the dosage (based on Al2O3) of AS, AS/PDM (0.55/20:1-3.99/5:1) composite coagulants are 4.24 mg/L, 3.96-1.87 mg/L, and the algae-removal rates are 83.00%, 87.52%-90.93% respectively. When dosage to raw water are 4.24 mg/L, the algae-removal rates of AS, AS/PDM (0.55/20:1-3.99/5:1) composite coagulants are 83.00%, 88.29%-97.66%, and the residual turbidities are 2.00 NTU, 1.76-0.43 NTU respectively. When dosage to chlorine-added water are 4.50 mg/L, the treatment effect of AS/PDM (1.53/10:1) composite coagulant to raw water is better than that of AS to chlorine-added water, and the treatment effect of AS/PDM (3.99/5:1) composite coagulant to raw water is better than that of AS, AS/PDM (0.55/20:1) and AS/PDM (1.53/10:1) composite coagulants to chlorine-added water. So using AS/PDM composite coagulants can enhance evidently the treatment effect of AS to winter Taihu Lake raw water. Compared with using AS solely, the dosage of AS in composite coagulants are saved when the residual turbidities are required in same level, and the treatment effect of AS is enhanced when the dosage of AS in composite coagulants are same as that of using AS solely. Moreover, using composite coagulants can replace the part chlorine-added function on increasing coagulation and algae-removal in prechlorination process and profitably increases safety of drinking water quality.


Assuntos
Compostos de Alúmen/química , Eucariotos/efeitos dos fármacos , Polietilenos/química , Compostos de Amônio Quaternário/química , Poluição da Água/prevenção & controle , Purificação da Água/métodos , China , Eucariotos/crescimento & desenvolvimento , Eutrofização , Água Doce/análise , Estações do Ano
16.
Huan Jing Ke Xue ; 29(8): 2195-200, 2008 Aug.
Artigo em Zh | MEDLINE | ID: mdl-18839572

RESUMO

A series of stable composite coagulants was prepared using polyaluminum chloride (PAC) and polydimethyldiallylammonium chloride (PDM) with different intrinsic viscosity as raw materials. The enhanced coagulation processes of summer high algae content Taihu lake raw water by using the composite coagulants were reported in this paper. Jar tests were used to study the influences of the composite ratios of PAC to PDM and the intrinsic viscosity of PDM on the turbidity removal and precipitating performance. The results showed that for the summer Taihu raw water with temperature of 28-30 degrees C and turbidity of 30-33 NTU, algae content of 2.6 x 10(7) cells/L. When 2NTU turbidity of supernatant from settlement tank was required according to the current process of potable water plant in Wuxi, the dosage of 7.00 mg/L PAC was necessary, the PAC/PDM composite coagulants with the ratios (m/m) of 20:1, 10:1, 5:1 only needed dosage ranges of 3.00-2.83 mg/L, 3.50-3.49 mg/L, 5.37-4.67 mg/L with the increasing of PDM intrinsic viscosity from 0.52 dL/g to 2.46 dL/g. And compared with PAC only used, composite coagulants could decrease the PAC dose by 57.14%-59.57%, 50%-50.14%, 23.29%-33.29% correspondingly. When residual turbidity of 1 NTU was required, the dosage of 10 mg/L were necessary for the treatment with PAC , composite coagulants with the ratios(m/m) of PAC to PDM of 20:1, 10:1, 5:1 and the different intrinsic viscocity of PDM needed dosage of 8.33-3.91 mg/L, and could decrease the PAC dose by 16.7%-60.9%. Therefore, the efficiency turbidity removal and precipitating performance of composite coagulants were remarkably, and the lower the ratios of PAC to PDM and the higher the intrinsic viscosity of PDM, the higher efficiency of turbidity removal.


Assuntos
Hidróxido de Alumínio/química , Eucariotos/crescimento & desenvolvimento , Polietilenos/química , Compostos de Amônio Quaternário/química , Poluição da Água/prevenção & controle , Purificação da Água/métodos , China , Eutrofização , Floculação , Estações do Ano
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