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Результаты 2901-2910 из 7,290
Role of carbon-dioxide sequestering bacteria for clean air environment and prospective production of biomaterials: a sustainable approach Полный текст
2022
Maheshwari, Neha | Thakur, Indu Shekhar | Srivastava, Shaili
The increase in demand of fossil fuel uses for developmental activity and manufacturing of goods have resulted a huge emission of global warming gases (GWGs) in the atmosphere. Among all GWGs, CO₂ is the major contributor that inevitably causes global warming and climate change. Mitigation strategies like biological CO₂ capture through sequestration and their storage into biological organic form are used to minimize the concentration of atmospheric CO₂ with the goal to control climate change. Since increasing atmospheric CO₂ level supports microbial growth and productivity thus microbial-based CO₂ sequestration has remarkable advantages as compared to plant-based sequestration. This review focuses on CO₂ sequestration mechanism in bacteria through different carbon fixation pathways, involved enzymes, their role in calcite, and other environmentally friendly biomaterials such as biofuel, bioplastic, and biosurfactant.
Показать больше [+] Меньше [-]The nexus between consumption-based carbon emissions, trade, eco-innovation, and energy productivity: empirical evidence from N-11 economies Полный текст
2022
Amin, Maaz | Zhou, Shengqi | Safi, Adnan
Unlike previous studies, this study attempts to fill the research gap in the area of consumption-based carbon emissions by introducing the role of energy productivity and eco-innovation along with international trade. To fill the mentioned research gap, the present study aims to evaluate the impact of eco-innovation and energy productivity on trade-adjusted consumption-based carbon emissions for the Next Eleven (N-11) economies using updated available data from 1995–2019. Further, on the methodological aspect, this study employed novel advanced panel data econometric techniques such as cross-sectional autoregressive distributed lags model (CS-ARDL), Westerlund cointegration test, and augmented mean group approach, which helps to tackle the problem of cross-section dependency and heterogeneity. The empirical outcomes confirm the long-run cointegrating relationship for consumption-based carbon emissions with exports, imports, gross domestic product, energy productivity, and eco-innovation. The results from CS-ARDL indicate that energy productivity, eco-innovation, and exports decrease carbon emissions by − 0.181%, − 0.0148%, and − 0.292%, respectively. However, economic growth and imports cause carbon emissions to increase by 1.201% and 0.225%, respectively. Moreover, the results also confirmed that any policy targeting energy productivity, exports, imports, gross domestic product, and eco-innovation should help to achieve equilibrium in approximately more than 1 year. This study recommends that the role of energy productivity and environment-related innovation is crucial for achieving the carbon neutrality target of the Next Eleven economies.
Показать больше [+] Меньше [-]Flood inundation evolution of barrier lake and evaluation of regional ecological spatiotemporal response—a case study of Sichuan-Tibet region Полный текст
2022
Jiang, Fengshan | Dai, Xiaoai | Xie, Zhiqiang | Xu, Tong | Yin, Siqiao | Qu, Ge | Yang, Shouquan | Zhang, Yangbin | Yang, Zhibing | Xu, Jiarui | Hou, Zhiqun
The Himalayan volcanic earthquake zone has significantly impacted China’s Sichuan-Tibet region. Many barriers have formed as a result of the earthquake and secondary disasters, such as landslides, which have blocked the river. The breach of the barrier lake seriously threatens the lives and property safety of downstream personnel. There has been little research on the surrounding ecology for the later treatment of the barrier lake. This paper aims to scientifically predict the risk of dam break in a barrier lake as well as to explore its impact on the ecological environment and put forward controllable measures. Based on four major barrier lake events in the Sichuan-Tibet area, Diexihaizi, Tangjiashan barrier lake, and so on, we extract water bodies from remote sensing images and use the HEC-RAS (Hydrologic Engineering Center of River Analysis System) model to investigate whether there is a dam break risk and the route of the dam break is predictable. Simultaneously, from 1990 to 2020, the smallest administrative region is located. The InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model is utilized to evaluate and analyze its habitat and create an evaluation based on flood inundation data. The results suggest that a stable barrier lake (such as Diexihaizi) has a sound effect on the habitat quality index following engineering treatment. The development of the barrier lake has altered the types of neighboring lands used and the natural patterns of the region’s landscape. The habitat quality index will marginally deteriorate within a 1-km radius of the barrier lake. However, the quality of habitats in the area ranging within 3 km and 5 km has improved. It is necessary to discharge and strengthen the barrier lake artificially. Human-controlled regions, according to studies, will recover higher habitat quality index values than other locations. Whether the barrier lake has a positive impact on the surrounding area, on the other hand, is primarily dependent on the original ecology. The development of barrier lakes is damaging and unprofitable in Tibet, where the actual ecology is better in the short term. Still, in Sichuan Province, where the habitat quality is relatively low, the appearance of dammed lakes has played a role in correcting the ecology.
Показать больше [+] Меньше [-]Biodiversity and degradation potential of oil-degrading bacteria isolated from sediments of hydrothermal and non-hydrothermal areas of the Southwest Mid-Indian Ocean Ridge Полный текст
2022
Shi, Haolei | Cheng, Jiangfeng | Gao, Wei | Ma, Meng | Liu, Ang | Hu, Tianyi | Han, Bin | Zheng, Li
In this study, sediments from eight sites were collected from hydrothermal areas (e.g., the Tiancheng, Tianzuo, and Longqi hydrothermal areas) and non-hydrothermal area on the Southwest Mid-Indian Ocean Ridge. Using crude oil as the only carbon and energy source, 162 strains of culturable oil-degrading bacteria were isolated and obtained. The rate of oil degradation of the consortia was 39.48–46.00% in hydrothermal and non-hydrothermal areas. High-throughput sequencing found that the alpha diversity indices (e.g., Shannon and Simpson) of the communities in hydrothermal areas were higher than those in non-hydrothermal area. The species diversities of the oil-degrading bacteria were different among different hydrothermal areas. The composition of the oil-degrading bacterial species in the Tianzuo hydrothermal area tended to be more similar to that in the non-hydrothermal area. This similarity is attributed to the changes in the bacterial community that followed the cessation of hydrothermal vent eruptions at this site. The Alphaproteobacteria abundance of the oil-degrading bacteria was significantly different in oil-degrading bacteria between the hydrothermal and non-hydrothermal areas.
Показать больше [+] Меньше [-]Association between meteorological factors and hospital admissions for uveitis in Hefei, China: a time-series study Полный текст
2022
Cao, Fan | He, Yi-Sheng | Xiang, Kun | Wan, Cheng-Huan | Liu, Wei | Gui, Yan-Chao | Pan, Hai-Feng | Jiang, Zheng-Xuan | Tao, Li-Ming
Meteorological variables are regarded as risk factors for inflammatory diseases, but their associations with uveitis, one of the leading causes accounting for blindness worldwide with an estimated prevalence of 38–714 cases/100,000 person-years, have not been thoroughly investigated. The present study explored the short-term association between meteorological variables and hospital admissions for uveitis in Hefei City, China. Daily data on uveitis hospital admissions and meteorological variables including mean temperature (MT) (°C), diurnal temperature range (DTR) (°C), and relative humidity (RH) (%), from 2014 to 2020, were collected. A time-series study using generalized linear model combined with distributed lag non-linear model was applied. Totally, 1911 admissions for uveitis including 894 first admissions and 1017 readmissions were reported during the study period. The associations of high percentile of MT (75th, 24.5℃) and low percentile of DTR (25th, 5.4℃) with uveitis admissions were observed to be statistically significant from lag9 (RR = 1.041, 95%CI: 1.002–1.081) to lag11 (RR = 1.053, 95%CI: 1.003–1.104) and lag4 (RR = 1.053, 95%CI: 1.019–1.088) to lag5 (RR = 1.052, 95%CI: 1.020–1.085), respectively. Moreover, a significant association between low percentile of RH (1th, 44%) and uveitis admissions appeared at lag0–8 (RR = 1.869, 95%CI: 1.017–3.434) and lasted until lag0–13 (RR = 2.539, 95%CI: 1.102–5.850) in the cumulative lag structure. Subgroup analyses indicated that males and the young seemed to be more sensitive to high MT exposure, while females appeared to be more vulnerable to low DTR exposure. Interestingly, both the young and the elderly are susceptible to low DTR and low RH exposure. Furthermore, high MT and low DTR exposure were associated with increased risk of first admission for uveitis. In summary, exposure to high-value of MT and low-value of DTR and RH may increase the hospital admissions for uveitis, especially for the status of first admission.
Показать больше [+] Меньше [-]Adsorption of basic fuchsin using soybean straw hydrolyzed by subcritical water Полный текст
2022
Caponi, Natiela | Silva, Luis F. O. | Oliveira, Marcos L. S. | Franco, Dison S. P. | Netto, Matias S. | Vedovatto, Felipe | Tres, Marcus V. | Zabot, Giovani L. | Abaide, Ederson R. | Dotto, Guilherme L.
The valorization of agro-industrial residues can be improved through their full use, making the production of second-generation ethanol viable. In this scenario, hydrolyzed soybean straw generated from a subcritical water process was applied to the basic fuchsin adsorption. At pH eight, a high adsorption capacity was obtained. The mass test results showed that basic fuchsin’s removal and adsorption capacity could be maximized with an adsorbent dosage of 0.9 g L⁻¹. The linear driving force model was suitable for predicting the kinetic profile, and the kinetic curves showed that equilibrium was reached with only 30 min of contact time. Besides, the Langmuir model was the best to predict the adsorption isotherms. The thermodynamic parameters revealed a spontaneous and endothermic process. At 328 K, there is maximum adsorption capacity (72.9 mg g⁻¹). Therefore, it can be stated that this material could be competitive in terms of adsorption capacity coupled with the idea of full use of waste.
Показать больше [+] Меньше [-]Treatment of Ammonium-Nitrogen–Contaminated Groundwater by Tidal Flow Constructed Wetlands Using Different Substrates: Evaluation of Performance and Microbial Nitrogen Removal Pathways Полный текст
2022
Xu, Dan | Ling, Huilan | Li, Zebing | Li, Yun | Chen, Renxiang | Cai, Shuo | Gao, Bai
As a significant oxygen intensified configuration, tidal flow constructed wetlands (TFCWs) are effective for the treatment of water and wastewater rich in NH₄⁺-N. The TFCWs filled with four substrates (gravel, granular active carbon, volcanic rock, and zeolite) were used to treat synthetic groundwater containing NH₄⁺-N. The results showed that higher ammonium removal was achieved in TFCW filled with zeolite (89.20 ± 3.09%) and granular active carbon (53.70 ± 8.91%). The highest accumulation of nitrate was obtained in TFCW filled with volcanic rock, whereas the lowest was obtained in TFCW filled with granular active carbon. The quantitative polymerase chain reactions (qPCR) and high-throughput sequencing of bacterial 16S rRNA pyrosequencing were applied to reveal the involved microbial N removal pathways. The abundance of amoA gene of Nitrospira and anammox gene of unclassified Planctomycetaceae suggested anammox could play a key role in NH₄⁺-N removal in the absence of organic carbon in the simulated groundwater. Besides, the results of adsorption isotherms showed that substrate adsorption coupled with anaerobic ammonium oxidation (anammox) were the major reason for the robust NH₄⁺-N removal performance in TFCW filled with zeolite.
Показать больше [+] Меньше [-]Impact of credit, liquidity, and systematic risk on financial structure: comparative investigation from sustainable production Полный текст
2022
Sadiq, Muhammad | Alajlani, Sami | Hussain, Muhammed Sajjad | Ahmad, Rashid | Bashir, Furrukh | Supat Chupradit,
The role of risk assessment and capital structure is vital for the sustainable growth of firms and increasing the shareholders’ wealth. This research explores the correlation between firm risk and capital structure using datasets from the sugar and cement sectors of Pakistan as a developing economy. This study is unique as it involved two firms of different nature (sugar firms operate seasonally while cement firms operate yearly) to view the real picture on the impact of risk and structure assessment on firms’ credibility and shareholders’ wealth. For this purpose, 15-year data (2000–2014) containing the financial statements of the target sectors were collected and the ANOVA analysis was applied with credit risk, liquidity risk, systematic risk, and firm size were used as the regressor variables, firm growth and dividend payout ratio as the control variables, and leverage as the regression variable. The findings showed that credit risk and liquidity risk are significantly correlated with leverage. This suggests that decision-makers pertaining to firms’ risk and efficiency must focus more on risk to pursue a stronger and sustainable increase in shareholder wealth.
Показать больше [+] Меньше [-]Does China’s carbon emission trading policy improve regional energy efficiency?—an analysis based on quasi-experimental and policy spillover effects Полный текст
2022
Zhang, Xue-mei | Lu, Fei-fei | Xue, Dan
Carbon emission trading policy is of great importance for addressing climate change and reducing carbon emissions. Reducing carbon emissions could further affect energy efficiency (EE). Based on the data from 30 provinces in China from 2006 to 2017, this paper first calculated EE by using the super slack-based model (Super-SBM) and then analysed the theoretical mechanism of the impact of carbon emission trading policy on EE. We also used a difference-in-difference (DID) model and mediation effect model for empirical analysis. Finally, we established the spatial difference-in-difference (SDID) model to test the policy spillover effects of carbon emission trading policy. The results showed that the high EE areas have gradually shifted to the central and eastern regions during 2006–2017 in China. The EE value in the pilot area of the carbon emission trading policy was obviously higher than that in the non-pilot area. Carbon emission trading policy had a significant positive effect on improving EE overall. In particular, green technology innovation and energy structure both had positive mediation effects on carbon emission trading policy affecting EE. However, the industrial structuring adjustment had no significant mediation effect in its influencing mechanism. Additionally, the spatial spillover effects test showed that the carbon emission trading policy had a positive effect on the EE of the pilot areas but a negative effect on that of the non-pilot areas.
Показать больше [+] Меньше [-]Occurrence of persistent organic pollutants and chlorpyrifos in Tadarida brasiliensis tissues from an agricultural production area in Argentina Полный текст
2022
González Noschese, Camila Sofía | Olmedo, María Luz | Seco Pon, Juan Pablo | Miglioranza, Karina Silvia Beatriz
Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) are lipophilic and persistent compounds, with chronic toxicity that cause negative effects on the environment and organisms. The chlorpyrifos is an organophosphate insecticide and represent the main insecticide currently used in many countries. The concentrations of OCPs, PCBs, and chlorpyrifos were evaluated in liver, muscle, and gonad of females and males of Tadarida brasiliensis in an agricultural production area in Argentina. Pollutants were quantified by gas chromatography with electron capture detection. The general total concentration pattern among tissues was gonad > muscle > liver, with a higher ratio of pesticides (OCPs + chlorpyrifos) over PCBs in muscle and liver, while gonads showed higher concentrations of PCBs. The predominance of DDTs and endosulfans evidences the bioavailability of these compounds despite their use has ceased. Chlorpyrifos was the main pesticide detected in almost all samples of both sexes, probably due to its current intensive use. More researches about ecology and activity patterns is paramount in order to understand more accurately the accumulation and possible negative effects of these pollutants.
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