خيارات البحث
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Nonlinear dependence between China’s carbon market and stock market: new evidence from quantile coherency and causality-in-quantiles النص الكامل
2022
Jiang, Yonghong | Liu, Lu | Mu, Jinqi
This study examines the nonlinear dependence between carbon market and stock market in China under normal and extreme market conditions by employing two novel nonlinear approaches, namely, quantile coherency and causality-in-quantiles methods. Given our results on the overall and sector level of stock market, we find that there is a negative dependence between the two markets under bearish and normal market states in the short- and medium-term respectively, while the dependence becomes positive under bearish and bullish market states in the long-term. Furthermore, we also prove that the Granger causality from carbon market to stock market exists. However, no evident impacts from stock market to carbon market have been found. Additionally, at sector stock market, we discover heterogeneity across market conditions. And emission-intensive sector stock indices are more affected by carbon prices.
اظهر المزيد [+] اقل [-]Environmental concerns of financial inclusion and economic policy uncertainty in the era of globalization: evidence from low & high globalized OECD economies النص الكامل
2022
Ullah, Sami | Ali, Kishwar | Shah, Salman Ali | Ehsan, Muhammad
Environmental consequences of financial aspects, policy uncertainties and rapid globalization is the topic of intense debate in present years. However, this study contribute to existing literature in an innovative way. We classified the 33 OECD economies in two group’s lower globalized economies (LGE) and highly globalized economies (HGE), based on their level of globalization. Considering the cross-sectional dependency and slope heterogeneity in the data this study employed the Augmented Mean Group method to estimate the influence of financial inclusion, economic policy uncertainty and globalization on the environment quality of both groups for the period 1996–2019. The results revealed a negative significant impact of financial inclusion, while a positive significant impact of economic policy uncertainty on CO2 emissions in both groups, LGE and HGE. However the globalization estimated to have positive impact on CO2 emission in LGE’s, in HGE’s it is significantly impeding the CO2 emission. The interaction of globalization with financial inclusion and economic policy uncertainty respectively found negative and positive to effect the CO2 in both LGE’s and HGE’s. The study suggests that, LGE’s are need to prepare for economic globalization, move toward adopting energy-efficient technology and promote trade in less-polluting products in order to sustain their environment quality. The outcomes of this study are robust by employing different model specifications.
اظهر المزيد [+] اقل [-]Quantifying the bioaccumulation of Pb to Chlorella vulgaris in the presence of dissolved organic matters with different molecular weights النص الكامل
2022
Shi, Zhiqiang | Du, Haiyan | Wang, Changhui | Xu, Huacheng
Dissolved organic matter (DOM) is ubiquitous in natural waters which exhibits obvious effects on the toxicity of heavy metals. However, information on the toxicity of heavy metals in the presence of DOMs with different molecular weights (MWs) was still unclear. In this study, Suwannee river humic acid (SRHA) and algae-derived organic matter (ADOM) were selected as typical terrestrial and microbial DOMs, with the bulk DOMs fractionating into high MW (HMW-, 1 kDa ~ 0.45 μm) and low MW (LMW-, < 1 kDa) fractions to explore the MW-dependent heterogeneities in the bioaccumulation of Pb to Chlorella vulgaris. Results showed that, regardless of DOM types, the LMW fraction exhibited more acidic groups and humic-like substances than the HMW counterparts. Presence of bulk DOM can decrease the bioaccumulation of Pb, while the specific effects were MW- and type-dependent. The LMW-SRHA enhanced the bioaccumulation of Pb while the HMW counterpart alleviated the effects. However, both the HMW- and LMW-ADOM can reduce the bioaccumulation of Pb to C. vulgaris. Moreover, the correlation analysis showed a significant positive correlation between the content of phenolic-OH and the adsorbed/internalized amounts of Pb, demonstrating that the phenolic-OH played a critical role in altering the bioaccumulation of Pb. The results obtained in this study suggest that distribution of MWs, number of acidic functional groups, and metal complexation capacity within DOM pool should be considered for the eco-environmental risk assessment of heavy metals in aquatic environments.
اظهر المزيد [+] اقل [-]Exogenous supplementation of Sulfur (S) and Reduced Glutathione (GSH) Alleviates Arsenic Toxicity in Shoots of Isatis cappadocica Desv and Erysimum allionii L النص الكامل
2022
Arianmehr, Mitra | Karimi, Naser | Souri, Zahra
The current study was conducted to investigate the role of sulfur (S) and reduced glutathione (GSH) in mitigating arsenic (As) toxicity in Isatis cappadocica and Erysimum allionii. These plants were exposed for 3 weeks to different concentrations (0, 400 and 800 μM) of As to measure fresh weight, total chlorophyll, proline and hydrogen peroxide (H₂O₂) content, As and S accumulation, and guaiacol peroxidase (POD) and glutathione S-transferase (GST) along with the supplementation of 20 mg L⁻¹ of S and 500 μM of GSH. Results revealed the significant reduction of fresh weight (especially in E. allionii), activities of POD and GST enzymes and proline content as compare to control. However, the application of S and GSH enhanced the fresh weight. Inhibition in H₂O₂ accumulation and improvement in antioxidant responses were measured with the application of S and GSH. Hence, the supplementation of S and GSH enhanced fresh weight and total chlorophyll in both I. cappadocica and E. allionii by alleviating the adverse effects of As stress via decreased H₂O₂ content and restricted As uptake.
اظهر المزيد [+] اقل [-]Biotechnological interventions in food waste treatment for obtaining value-added compounds to combat pollution النص الكامل
2022
Sreekala, Aparna Ganapathy Vilasam | Ismail, Muhammad Heikal Bin | Nathan, Vinod Kumar
Over the last few decades, the globe is facing tremendous effects due to the unnecessary piling of municipal solid waste among which food waste holds a greater portion. This practice not only affects the environment in terms of generating greenhouse gas emissions but when left dumped in landfills will also trigger poverty and malnutrition. This review focuses on the global trend in food waste management strategies involved in the effective utilization of food waste to produce various value-added products in a microbiology aspect, thereby diminishing the negative impacts caused by the unnecessary side effects of non-renewable energy sources. The review also detailed the efficiency of microorganisms in the production of various bio-energies as well. Further, recent attempts to the exploitation of genetically modified microorganisms in producing value-added products were enlisted. This also attempted to address food waste valorization techniques, the combined applications of various processes for an enhanced yield of different compounds, and addressed various challenges. Further, the current challenges involved in various processes and the effective measures to tackle them in the future have been addressed. Thus, the present review has successfully addressed the circular bio-economy in food waste valorization.
اظهر المزيد [+] اقل [-]Centella asiatica extract protects against cisplatin-induced hepatotoxicity via targeting oxidative stress, inflammation, and apoptosis النص الكامل
2022
This study was designed to investigate the protective effects of Centella asiatica (CA) on cisplatin-induced hepatotoxicity and to clarify the underlying mechanism by biochemical, molecular, immunohistochemical, and histopathological analyses. Rats were pre-treated with two doses of CA (100 and 200 mg/kg, p.o.) for 14 consecutive days. Then, on the 15th day, hepatotoxicity was induced by a single cisplatin injection (10 mg/kg i.p.). On the 18th day, the rats were euthanized. CA effectively alleviated cisplatin-induced hepatic injury via reduction in AST, ALT, and ALP enzymes and a decrease in oxidative stress (decreased MDA and ROS, and increased SOD, CAT, and GSH). CA also mitigated the inflammatory damage by the inhibition of TNF-α, IL-1β, and NF-κB. The liver expression of caspase-3 and Bax was downregulated, while Bcl-2 was upregulated. Moreover, immunohistochemical results confirmed the recovery with CA by downregulation of iNOS and 8-OHdG expression. These results showed that with its antioxidant, anti-inflammatory, and anti-apoptotic activities, CA could help alleviate the hepatotoxic effects of cisplatin chemotherapy.
اظهر المزيد [+] اقل [-]Screening of various Brassica species for phytoremediation of heavy metals-contaminated soil of Lakki Marwat, Pakistan النص الكامل
2022
Natural resources, especially agrarian soils, have been much contaminated with various pollutants including heavy metals since industrial revolution, so it is pertinent to utilize green technology, the so-called phytoremediation technology for reclamation of heavy metal-contaminated soils. A pot experiment was conducted to screen four different species (Brassica juncea, Brassica napus, Brassica rapa, Brassica campestris) of Brassicaceae family for the remediation of HMs contaminated soil of Lakki Marwat city, Pakistan, irrigated with municipal wastewater. Plants were analyzed for various morpho-physiological, biochemical, and phytoextraction factors like bioaccumulation (BAF) and translocation factor (TF). Results showed maximum morpho-physiological responses including seed germination, chlorophyll content, root fresh and dry weights, and shoot fresh and dry weights in B. juncea followed by B. napus, B. campestris, and B. rapa. Plant biochemical analyses of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) also exhibited maximum activity in B. juncea followed by B. napus, B. campestris, and B. rapa, respectively, in both control and contaminated soils. Conversely, plant oxidative stress markers including malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) showed maximum contents in B. rapa followed by B. campestris, B. napus, and B. juncea in both soils. Plant bioconcentration factors i.e. BAF and TF measured for all species in both soils confirmed that B. juncea accumulated maximum heavy metals. Similarly, enhanced phytoextraction capacity was noticed for all Brassica species in decreasing order i.e. B. napus > B. campestris > B. rapa. Hence, all the results confirmed that B. juncea excelled and can be recommended for phytoremediation purpose in soils of study area.
اظهر المزيد [+] اقل [-]Analysis of regional differences and dynamic mechanisms of agricultural carbon emission efficiency in China's seven agricultural regions النص الكامل
2022
A profound understanding of the present status and regional characteristics of China’s agricultural carbon emissions (ACE) is the basic prerequisite for exploring a pathway to ACE reduction that is compatible with China’s national conditions. This study uses the inter-provincial agricultural industry panel data from 2001 to 2017 and selects the three-stage slack-based measure data envelope analysis (SBM-DEA) model and Malmquist-Luenberger(ML) index model to measure the dynamic efficiency of agricultural carbon emissions (ACE). Additionally, this study uses the Dagum Gini coefficient and the panel vector auto-regression(PVAR) model to analyze the sources of regional differences in dynamic efficiency and the internal structure, respectively. The empirical results reveal the following: (i) The dynamic efficiency of China’s ACE is in a state of “efficiency optimization.” Although both technological change and technological efficiency change are in an “efficient” state, they also show a decline in technological efficiency change and a regression in technological change, respectively. (ii) The overall Dagum Gini coefficient of China’s ACE dynamic efficiency, technological change, and technological efficiency change all demonstrate upward trends. The gap between regions is the main reason for the long-term gap between the dynamic efficiency of China’s ACE, technological change, and technological efficiency change. (iii) Regardless of the time horizon, technological change has always been the main driving force for the continuous growth of dynamic efficiency; the contribution of technological change to dynamic efficiency is far greater than that of technological efficiency change. This conclusion has been verified in samples from different regions of China.
اظهر المزيد [+] اقل [-]A bibliometric analysis of sustainable agriculture: based on the Web of Science (WOS) platform النص الكامل
2022
Sarkar, Apurbo | Wang, Hongyu | Rahman, Airin | Memon, Waqar Hussain | Qian, Lu
The global trends of sustainable agriculture (SA) have expanded dramatically through many scholarly studies in this area. Many literary works have focused on several aspects of sustainable agriculture (SA), such as the effectiveness of pesticide management, impacts on cultivation and enhancement, quantifying with soil, water, and air, agro-ecological activities, ecological aspects, and other areas of focus. The review offers a structured bibliometric and network evaluation that will profoundly observe the recent trends of SA, which other studies in this field have not comprehensively analyzed before. The study’s prime objectives are to investigate the progress, trends and themes, and provide a comprehensive mapping of the field of sustainable agriculture. The study utilizes the Web of Science core collection database to search, filter, and extract the published article from 1992–2020. The review commences by exploring over 3000 journal articles, those then filtered into some well-recognized matrix of impacts and published by impactful journals, institutions, and authors. The results indicate a stable growth in publications since 2006, with a sharp improvement from 2010. Thematic assessment of key concepts by exploring the abstract discovered a robust emphasis on quantitative resource associations within a strong subjective focus with farm capacities and inner-sectorial dominations. We reveal how the outcome may assist the sectors to facilitate better understandings and comprehend the challenging transitions based on brainstorming to action formulation.
اظهر المزيد [+] اقل [-]Exposure to chemical substances and particles emitted during additive manufacturing النص الكامل
2022
Dobrzyńska, Elżbieta | Kondej, Dorota | Kowalska, Joanna | Szewczyńska, Małgorzata
Additive manufacturing is an innovative technology that allows the production of three-dimensional objects replicating digital models. The aim of this study was to identify whether the use of this technology in a room without mechanical ventilation system may pose a health risk to its users due to the emission of chemical compounds and fine particles. Measurements were conducted in a furnished space with natural ventilation only, during additive manufacturing on a fused deposition modeling printer with 9 different filaments. Both chemicals and particles were sampled. Volatile organic compounds and phthalic acid esters were determined by gas chromatography–mass spectrometry detection. Carbonyl compounds were determined using the high-performance liquid chromatography with diode-array detection method. Fine particle emission studies were carried out using a DiSCmini particle counter (Testo). In the air samples, numerous chemical substances were identified including both the monomers of the individual materials used for printing such as styrene and other degradation products (formaldehyde, toluene, xylenes). Moreover, 3D printing process released particles with modal diameters ranging from 22.1 to 106.7 nm and increased the number concentration of particles in the workplace air. The results of analyses, depending on the type of material applied, showed the presence of particles and chemical substances in the working environment that may pose a risk to human health. Most of the identified substances can be harmful when inhaled and irritating to eyes and skin.
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