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Exploring multifunctional antioxidants as potential agents for management of neurological disorders Texte intégral
2022
Sindhu, Rakesh K. | Prabhjot Kaur, | Kaur, Parneet | Singh, Harmanpreet | Batiha, Gaber El-Saber | Verma, Inderjeet
Free radical or oxidative stress may be a fundamental mechanism underlying several human neurologic diseases. Therapy using free radical scavengers (antioxidants) has the potential to prevent, delay, or ameliorate many neurologic disorders. However, the biochemistry of oxidative pathobiology is complex, and optimum antioxidant therapeutic options may vary and need to be tailored to individual diseases. In vitro and animal model studies support the potential beneficial role of various antioxidant compounds in neurological disease. Antioxidants generally play an important role in reducing or preventing the cell damage and other changes which occur in the cells like mitochondrial dysfunction, DNA mutations, and lipid peroxidation in the cell membrane. Based on their mechanism of action, antioxidants can be used to treat various neurological disorders like Huntington’s disease, Alzheimer’s disease, and Parkinson’s disease. Vitamin E has a scavenging action for reactive oxygen species (ROS) and also prevents the lipid peroxidation. Creatine generally reduces the mitochondrial dysfunction in Parkinson’s disease (PD) patients. Various metal chelators are used in PD for the prevention of accumulation of the metals. Superoxidase dismutase (SOD), lipases, and proteases act as repair enzymes in patients with AD. Accordingly, the antioxidant defense system is found to be most useful for treating various neurological disorders.
Afficher plus [+] Moins [-]Radiotoxic 210Po in Some Marine Species of the Marmara Sea (Tekirdağ) and Investigation of Chemical Yield of Various Metals Used in the Spontaneous Deposition Method Texte intégral
2022
Hafızoğlu, Nurgül | Sahin, Latife | Ganioğlu, Ela | Toklu Alıçlı, Benin
The ²¹⁰Po radionuclide concentrations of some marine organisms (Eriphia verrucosa, Solea solea, Mytilus galloprovincialis, Ulva lactuca) obtained from the northern part of the Sea of Marmara (Tekirdağ) in 2019 are presented in this study. The spontaneous radiochemical processes for ²¹⁰Po deposition in these marine species were performed by using three various metal discs. The ²¹⁰Po deposition yields of different species on silver, stainless steel and aluminium discs was investigated, and then, the disc with the best chemical deposition yield was determined. The ²¹⁰Po activity concentrations of E. verrucosa samples were measured to be 6.3 ± 0.8 Bq kg⁻¹ on silver disc, 5.9 ± 1.4 Bq kg⁻¹ on stainless steel disc and 3.4 ± 2.1 Bq kg⁻¹ on aluminium disc. The ²¹⁰Po activity concentrations of S. Solea on silver, stainless steel and aluminium discs were found to be 15 ± 2 Bq kg⁻¹, 11 ± 3 Bq kg⁻¹ and 4.8 ± 2.4 Bq kg⁻¹, respectively. The ²¹⁰Po specific activities of M. galloprovincialis samples taken in port for silver, stainless steel and aluminium discs were 39 ± 4 Bq kg⁻¹, 23 ± 8 Bq kg⁻¹, and N.M. (not measurable), respectively. Also M. galloprovincialis samples collected outside the port had the ²¹⁰Po concentrations of 57 ± 6 Bq kg⁻¹ and 21 ± 8 Bq kg⁻¹ on silver and stainless steel. While the ²¹⁰Po concentrations for out of port U. lactuca samples were found to be 60 ± 6 Bq kg⁻¹ for silver, 49 ± 12 Bq kg⁻¹ for stainless steel and 39 ± 15 Bq kg⁻¹ for aluminium, the ²¹⁰Po concentrations for in port U. lactuca on silver were determined to be 19 ± 3 Bq kg⁻¹. The annual effective ingestion doses from the consumption of E. verrucosa, S. solea, M. galloprovincialis and U. lactuca species were also calculated.
Afficher plus [+] Moins [-]Can the Leading Officials’ Accountability Audit of Natural Resources policy stimulate Chinese heavy-polluting enterprises’ green behavior? Texte intégral
2022
Liu, Yunqiang | She, Yanan | Liu, Sha | Tang, Hong
Under the pressure of environmental crisis caused by production and economic development, a policy for Leading Officials’ Accountability Audit of Natural Resources (LOAANR) was issued in 2014 to reduce the environmental risks and gain high-quality economy. Taking LOAANR policy as the research object, and based on 2011 to 2018 panel data from Chinese heavy-polluting enterprises, this paper employed a two-way fixed difference-in-differences (DID) model to explore the relationship between the LOAANR, environmental costs (ECs) and green innovation (GI). It was found that the implementation of the LOAANR significantly promoted enterprise GI, with the regulating impact mechanism, EC. GI efficiency was measured by continuous DID method. A heterogeneity analysis revealed that non-state-owned enterprises (NSOEs) were more eager to environmentally innovate. A corporate life cycle heterogeneity analysis of the GI policy effect found that the policy effect was negative in the decline stages. Compared with the eastern Chinese enterprises, enterprises in other regions were found to be more prone to positively adopting GI to maximize benefits in the face of the LOAANR. The policy was observed to have inhibited GI in central Chinese enterprises. It was also demonstrated that the policy effect has time and regional dynamic effect. Common trend, placebo, PSM-DID tests, and another robustness regressions were applied to support the conclusions. All the findings are expected to provide basic theoretical guidance for more environmental policies and high-quality production.
Afficher plus [+] Moins [-]Research on the policy synergy of supply-side and demand-side environmental policies: an analysis based on green value chain of manufacturing enterprises Texte intégral
2022
Ye, Chunmei | Wu, Lihua
An enterprise’s green value chain comprises a multitude of factors and links for a successful green transformation, and relevant environmental policies are multi-dimensional and multi-sectional. Environmental policies can affect the enterprise’s green development through stimulating the supply of green services or by increasing the demand for green products. Based on 346 policy statements issued by various government departments from 2000 to 2020, this paper matches the “type” of environmental policy with the “dimension” of value chain of manufacturing companies, establishing a coordination model and a co-existing network to measure how both elements interact. The results indicate a notable phenomenon with the Chinese government’s enterprise environmental policies, which can be described as “heavy supply-driven, light demand-pull.” A strong emphasis is put on the supply side of policies, in particular for the technology innovation sector, but the demand end of policies is comparatively minimal. The synergy between the policies and the links in the green value chain is divergent, which replicates the “heavy end-treatment, light front-prevention” seen with existing policies. Policy synergy at the end of the value chain such as the green production process is more mature and well-integrated, while the synergy for green product development lacks policies on both ends. The mismatch and imbalance of policies limits the overall level of green transformation for manufacturing enterprises.
Afficher plus [+] Moins [-]The positive effects of arbuscular mycorrhizal fungi inoculation and/or additional aeration on the purification efficiency of combined heavy metals in vertical flow constructed wetlands Texte intégral
2022
Xu, Zhouying | Li, Kaiguo | Li, Wenxuan | Wu, Chen | Chen, Xi | Huang, Jun | Zhang, Xiangling | Ban, Yihui
Inoculation with arbuscular mycorrhizal fungi (AMF) and additional aeration (AA), as two approaches to improve the functioning of treatment wetlands, can further promote the capacity of wetlands to purify pollutants. The extent to which, and mechanisms by which, AMF and AA purify wetlands polluted by combined heavy metals (HMs) are not well understood. In this study, the effects and mechanisms of AMF and/or AA on combined HMs removal in vertical flow constructed wetlands (VFCWs) with the Phragmites australis (reeds) were investigated at different HMs concentrations. The results showed that (1) AA improved the AMF colonization in VFCWs and AMF accumulated the combined HMs in their structures; (2) AMF inoculation and/or AA significantly promoted the reeds growth and antioxidant enzymes activities, thereby alleviating oxidative stress; (3) AMF inoculation and AA significantly enhanced the removal rates of Pb, Zn, Cu, and Cd under the stress of high combined HMs concentrations comparing to the control check (CK) treatment (autoclaved AMF inoculation and no aeration), which increased by 22.72%, 30.31%, 12.64%, and 50.22%, respectively; (4) AMF inoculation and/or AA significantly promoted the combined HMs accumulation in plant roots and substrates and altered the distribution of HMs at the subcellular level. We therefore conclude that AMF inoculation and/or AA in VFCWs improves the purification of combined HM-polluted water, and the VFCWs-reeds-AMF/AA associations exhibit great potential for application in remediation of combined HM-polluted wastewater.
Afficher plus [+] Moins [-]Extreme climatic effects hamper livestock production in Somalia Texte intégral
2022
Warsame, Abdimalik Ali | Sheik-Ali, Ibrahim Abdukadir | Hassan, Abdullahi Abdirahman | Sarkodie, Samuel Asumadu
Given the enormous impact of the livestock sector on Somalia’s economy and its vulnerability to climate variations, this study investigates short and long-term changes in climatic effects on livestock production by using data spanning from 1985 to 2016. To this end, the ARDL bounds testing and causality techniques were employed to model the long-run and short-run relationships, and direction of causality among sampled variables. Overall, the empirical results confirmed the existence of a stable long-run cointegration between variables. Rainfall and temperature patterns were found to have a significant positive and negative impact on livestock production both in the long run and short run, respectively. The observed carbon dioxide emissions have no significant impact on livestock production in the long run but enhance livestock production in the short run. Interestingly, growth in rural population declines livestock production in the long run but not in the short run. Besides, a unidirectional causality is confirmed from temperature to rainfall and CO₂ whereas livestock production has a bidirectional causal relationship with rainfall and temperature. While CO₂ emissions granger cause livestock production, a unidirectional causation is observed from rural population to temperature and livestock production. This study suggests adaptation and mitigation policies that combat the negative consequences of climate change.
Afficher plus [+] Moins [-]Preparation of Zr/Y co-doped TiO2 photocatalyst and degradation performance of hydroquinone Texte intégral
2022
Tao, Xiumei | Zhu, Lei | Wang, Xun | Chen, Xueqi | Liu, Xian
In this paper, Y–ZrO₂–TiO₂ photocatalyst was prepared by sol–gel method, the titanium source was tetrabutyl titanate, and the precursors were zirconium nitrate pentahydrate and yttrium nitrate hexahydrate. For the photocatalytic effect of Y–ZrO₂–TiO₂ to hydroquinone, these effects were investigated: doping ratios of Zr/Y, calcination conditions, pH, etc. And the materials were characterized by XRD, TEM-EDS, XPS, PL, ESR, etc. The results showed that the optimum preparation conditions of Y–ZrO₂–TiO₂ photocatalyst were as follows: the molar ratio of doping was Ti: Zr: Y = 100:6:0.5, the calcination temperature was 500 °C, and the calcination time was 2 h; the optimum reaction conditions were as follows: the dosage of Y–ZrO₂–TiO₂ was 1 g/L, and pH value was 6.96. The degradation rate of hydroquinone under 365-nm UV lamp for 50 min could reach 96.58%, while the degradation rates of pure TiO₂, Y–TiO₂, and ZrO₂–TiO₂ under the same conditions were 33.95%, 79.55%, and 90.30%, respectively. It can be seen that the addition of elements Zr and Y improves the photocatalytic performance of TiO₂.
Afficher plus [+] Moins [-]Nuclear energy consumption and energy-driven growth nexus: a system GMM analysis of 27 nuclear utilizing countries across the globe Texte intégral
2022
Duran, Mahmut Sami | Bozkaya, Şeyma | Onifade, Stephen Taiwo | Kaya, Mustafa Göktuğ
While the general environmental quality level continues to decline in today’s global economy, aggregate energy consumption levels are often linked to countries’ economic growth and environmental performances, thereby overlooking the specific roles of individual energy types. Thus, this study focuses on examining nuclear energy consumption-growth nexus in 27 selected nuclear energy–consuming countries across the globe. The system GMM estimator was applied to available post-2008 global financial crisis data spanning from 2010 to 2020 while accounting for influential factor inputs (labor and capital) within the framework of the traditional growth model. The results posit that both capital and labor significantly induce economic growth levels among the countries, while nuclear energy consumption is not a significant driver of growth levels despite some evidence of its positive roles. Hence, more investments in nuclear energy production are recommended to trigger an overall consumption level that will not only yield significant desirable economic growth impacts among the countries but also enhance possible environmental benefits in contrast to the growing environmentally detrimental fossil energy consumption among the countries.
Afficher plus [+] Moins [-]Chemical stabilization of heavy metals in municipal solid waste incineration fly ash: a review Texte intégral
2022
Zhao, Xin-yue | Yang, Jin-yan | Ning, Ning | Yang, Zhi-shan
Sufficient attention should be attached to the large amount of fly ash containing high levels of toxic heavy metals generated after municipal solid waste incineration. Because heavy metals could be leached out of the fly ash under specific conditions, it is necessary to stabilize the heavy metals in fly ash before landfill disposal. Processing technologies of incineration fly ash include solidification/stabilization technology, thermal treatments, and separation processes. This study reviewed the current treatment technologies of municipal solid waste incineration (MSWI) fly ash, with the main focus on the treatment of heavy metals in fly ash with chemical stabilization. Chemical stabilization processes involve chemical precipitation of heavy metal and chelation of heavy metals. In multiple studies, chemical stabilization technology has shown practical feasibility in terms of technology, economy, and effect. In addition, the combination of two or more stabilization agents broadens the general applicability of the agents to heavy metals and reduces the cost. The application of joint processing technology realizes the remove of soluble salt from fly ash. To minimize pollutants while increase their usable value, effective use of waste and co-disposal of several kinds of wastes have gradually become the research hotspots. New developments in chemical stabilization are progressively moving towards the sustainable direction of harmlessness and resource utilization of MSWI fly ash.
Afficher plus [+] Moins [-]Association between dietary quality indices and serum polychlorinated biphenyls and organochlorine pesticides levels among Lebanese adults Texte intégral
2022
Harmouche-Karaki, Mireille | Mahfouz, Maya | Helou, Khalil | Obeyd, Jawaher | Salameh, Pascale | Matta, Joseph | Narbonne, Jean-François
Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) remain a global concern in both developed and developing countries. Given that diet constitutes the major route of exposure to these pollutants, the objective of the current study is to investigate PCBs and OCPs serum levels in relation to dietary quality indices in a sample of Lebanese adults. Sociodemographic, nutritional, and anthropometric data were obtained from 302 participants in face-to-face interviews. Nutritional intakes from a previously validated quantitative 164-item food frequency questionnaire were used to calculate six a priori dietary indices: Healthy Eating Index (HEI-2015), alternate Healthy Eating Index (aHEI), Diet Quality Index-International (DQI-I), Mediterranean Diet Quality Index (Med-DQI), Med-DQIf, Mediterranean Diet Scale (MDS), and Mediterranean Diet Score (MedDietScore). Serum levels of six indicator PCBs (PCBs 28, 52, 101, 138, 153, 180) and four OCPs (HCB, β-HCH, DDT, and DDE) were investigated in relation to diet quality indices. Individuals with a higher adherence to the HEI-2015 and to the Mediterranean diet assessed by the Med-DQI/Med-DQIf displayed increased levels of OCPs (HCB, βHCH, DDT, and DDE). An inverted U-shaped association was observed between DQI-I and PCBs serum levels (PCBs 138, 153, 180, and ƩPCBs). This is the first study in the Middle East and North Africa region to investigate the association between POPs serum levels and a substantial number of a priori dietary indices. The impact of different food combinations and nutrient interactions on pollutants body burden and toxicity remains to be established in future studies.
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