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Exploring the strategies of online and offline recycling channels in closed-loop supply chain under government subsidy Texte intégral
2022
Huang, Yanting | Liang, Yuqing
The influence of online and offline dual recycling channels in a closed-loop supply chain (CLSC) is investigated in our work. The CLSC models of three recycling modes (single online recycling, single offline recycling, and dual recycling channels of online and offline) are established, respectively, and the impact of government subsidies on the pricing decision-making and recycling mode selection of channel members is therefore researched. The study found that the remanufacturer sets appropriate recycling price and transfer price to coordinate online and offline recycling channels and maximize its profits in the dual recycling modes; collector’s offline recycling faces the competitive threat of remanufacturers’ online recycling under the dual recycling modes, so the collector prefers a single offline recycling mode; the relationship between the collection quantities of the three modes depends on consumers’ preference of the online recycling channel. In the meanwhile, it is illustrated that government subsidy plays a positive role in promoting the recycling and remanufacturing willingness of remanufacturers and collectors. This work provides practical insights for the CLSC system to make recycle decisions.
Afficher plus [+] Moins [-]Road transportation green productivity and its threshold effects from environmental regulation Texte intégral
2022
Xu, Hao | Wang, Yeqing | Gao, Chenchen | Liu, Hongwei
This paper uses the global Malmquist–Luenberger index to investigate changes in road transportation green productivity from 2010 to 2017, incorporating undesirable outputs into the analytical framework. Furthermore, the relationship between environmental regulation and green productivity is tested by the panel threshold model. At the area level, the improvement of green productivity in western China benefits from a catch-up effect and improved scale efficiency. Moreover, the driving factor improving green productivity in China’s central and eastern areas is mainly the scale economy, and technology regress is the hindering factor. Research and development investment and government fiscal expenditure both show a single-threshold effect on green productivity. That is, their values in relation to thresholds cause differences in the impact of environmental regulation on green productivity. Our analysis shows that economic development can significantly promote green productivity, while highway density can significantly hinder it. Based on the evidence presented, we put forward practical suggestions for improving green productivity.
Afficher plus [+] Moins [-]The payment scheme for ecosystem services in the coastal city based on the ecosystem services value and current payment efficiency: a case study in Jimo of Qingdao city, China Texte intégral
2022
Wang, Jingpeng | Wang, Jinman | Zhang, Min | Zhang, Yafu | Wang, Jin | Zhu, Qiuping | Li, Sijia
The reasonable strategies of payment for ecosystem services (PES) play a key role in solving the contradiction between ecological protection and economic development in coastal cities. However, at present, the payment efficiency is relatively low and the determination method of PES is lack. Therefore, in this study, the Jimo district of Qingdao city in China, a typical coastal city, was selected as study area, and the equivalent factor method and marine ecological capital assessment method were used to obtain terrestrial and marine ecosystem services value (ESV) and its tempo-spatial variations from 2010 to 2018. Moreover, the payment efficiency of the sea area and 15 towns over 8 years was measured using the Super-efficient SBM-DEA model based on undesired output. ESV presented a clear reduction over 8 years. The marine ecosystem provided the main service value, and waste treatment, water regulation, and soil formation were the top 3 main functions in the land ecosystem. Regulating services provided the highest component among all functions. The high-value areas were mainly distributed in the northeast and northwest regions and the low-value areas were in the south-central regions. The average payment efficiency of the sea area and 15 towns over 8 years shown a stable trend at a low level. On the basis of the evaluation of ESV and efficiency, a new possible payment scheme including payment order and quota was proposed. The total quota of marine ecosystem was 5.226 billion RMB (88% of the total) and of terrestrial ecosystem was 0.713 billion RMB. Tian Heng, Jin Kou, Yi Fengdian, and Ling Shan are the first 4 priority towns, with compensation amounts of 0.205, 0.083, and 0.063 billion RMB respectively, while the last 3 towns are Tong Ji, Huan Xiu, and Chao Hai accounting for 6.02% of the total. The theoretical payment total quota was 5.939 billion RMB, and which accounted for a low proportion of local GDP. The study can provide some recommendations for making the reasonable and feasible payment schemes for ecosystem services in coastal city, and it is feasible in the practice of ecological environment protection and sustainable development.
Afficher plus [+] Moins [-]Gestational exposure to PCB-118 impairs placental angiogenesis and fetal growth Texte intégral
2022
Ge, Caiyun | Geng, Ting | Cheng, Lin | Zhang, Yuanzhen
Maternal exposure to polychlorinated biphenyls (PCBs) results in adverse effects on fetal development. However, the underlying mechanism has not been sufficiently explored in respect to particular PCBs. Placental angiogenesis plays a crucial role in feto-maternal substances transportation and fetal development. The present study was conducted to investigate the effects of prenatal PCB118 exposure on placental angiogenesis and fetal growth. The pregnant dam received PCB118 at environmentally relevant doses (0, 20, or 100 μg/kg/day) intragastrically from gestational day (GD) 7.5–18.5 to establish an in vivo model. Compared with the control group, the fetal body and placental weights of the PCB118 (100 μg/kg/day) group were significantly decreased and the intrauterine growth retardation (IUGR) rates were increased both in the female and male fetus. Furthermore, we found that placental histology was significantly impaired and the number of blood vessels was decreased in the PCB118 group. Additionally, gestational exposure to PCB118 caused anomalous mRNA expression of the genes in the placenta regarding angiogenesis. These findings indicate that PCB118 may contribute to the occurrence of IUGR by provoking placental angiogenesis dysfunction. This study clarified the adverse effects and potential mechanism of prenatal PCBs exposure on fetal growth, providing a new theoretical and experimental basis for future treatment and prevention.
Afficher plus [+] Moins [-]Study of a surface coating present on a Renaissance Piety from the Museum of Ancient Art (Castello Sforzesco, Milan) Texte intégral
2022
Fermo, Paola | Colella, Mario | Malagodi, Marco | Fiocco, Giacomo | Albano, Michela | Marchioron, Silvia | Guglielmi, Vittoria | Comite, Valeria
The surface coating present on a marble Piety dating to the Renaissance period and stored at the Castello Sforzesco-Museum of Ancient Art (Milan, Italy) was studied and chemically characterised. For this purpose, both portable non-invasive (XRF and colorimetric measurements) and micro-invasive techniques (FTIR-ATR and SEM-EDS), have been applied. The statue has been recently submitted to a restoration, since its surface appeared dark and yellowed, before an exhibition at the Louvre Museum and the original appearance of the marble surface recovered thanks to the surface coating removal. Through the analytical characterisation carried out before and after the marble cleaning, the presence of a degradation layer composed by gypsum was evidenced on the stone. The origin of this layer is ascribable to the exposure of the statue to outdoor environment and interaction with atmospheric pollution. The chemical nature of the coating applied at the end of nineteenth century also responsible for the surface alteration was hypothesized.
Afficher plus [+] Moins [-]Anthropogenic particles in coypu (Myocastor coypus; Mammalia, Rodentia)’ faeces: first evidence and considerations about their use as track for detecting microplastic pollution Texte intégral
2022
Gallitelli, Luca | Battisti, Corrado | Pietrelli, Loris | Scalici, Massimiliano
Anthropogenic plastic litter is widespread in all environments, with particular emphasis on aquatic habitats. Specifically, although freshwater mammals are important as they are at the top of food web, research mainly focus on marine animals, while only few studies have been carried out on freshwater mammals. The main gap is that microplastics (MP) are completely understudied in freshwater mammals. Here, we reported the first evidence of the presence of anthropogenic particles (including MP) in coypu (Myocastor coypus)’ faeces. Coypu is a rodent mammal inhabiting rivers and wetland areas, and we discussed our preliminary data suggesting the use of these tracks as possible future bioindicator of MP pollution in wetlands and freshwaters. We collected 30 coypu’s faeces in “Torre Flavia wetland” nature reserve. Then, in laboratory, faeces were digested in 30 ml hydrogen peroxide (30%) for a week a 20 °C and analysed under stereoscope. All the suspected found MP were isolated in a petri dish, using FT-IR analysis to confirm the polymers. Overall, we recorded 444 natural and anthropogenic particles with most of items being fibres. FT-IR analysis of the 10% of the particles recovered revealed that 72% of them was not MP (mainly, polyethylene, polyethylene terephthalate, and polyamide). Also, the number of anthropogenic particles is not correlated with the faecal weight. Given that alien species, such as coypu, are widespread species, our results might have a great importance as these species and MP in faecal tracks may be used as undirect proxy of environmental bioavailability of MP pollution.
Afficher plus [+] Moins [-]Evaluation of the pollutant interactions between different overlying water and sediment in simulated urban sewer system by excitation-emission matrix fluorescence spectroscopy Texte intégral
2022
Liao, Zhenliang | Chu, Jiangyong | Zhou, Shuangyu | Chen, Hao
The water quality in the sewer systems can be significantly influenced by the interaction between sediment and overlying water, which are still many doubts about the impact of pollutants transformation, degradation sequence, and reaction time. In this study, the exchanging processes between sewer sediment and four different overlying waters were evaluated in simulated urban sewer systems (dark and anaerobic environments). Dissolved organic matter (DOM) was used as an indicator to reflect the mitigation and exchange processes of pollutants. Excitation-emission matrix (EEM) fluorescence spectroscopy coupled with parallel factor analysis (PARAFAC) as an effective method for deciphering DOM properties was applied. There are three findings: (1) Three main processes (biological degradation, desorption, and adsorption) happened in the simulated sewer systems, in which the predominant pathway in the interaction process is biological degradation though consuming amino acid components. (2) The characteristics of overlying water could induce significant changes in sediment signatures; the amino acid-like components are more susceptible to degradation, and the humic-like compositions are more readily absorbed by sediments. (3) The reaction time is another significant factor (14 days was the turning point of the processes). This study unravels the transformation processes in sediment and different overlying waters, which provides the theoretical foundation for urban sewer efficient management and operation.
Afficher plus [+] Moins [-]Balneotherapy year in review 2021: focus on the mechanisms of action of balneotherapy in rheumatic diseases Texte intégral
2022
Cheleschi, Sara | Tenti, Sara | Seccafico, Iole | Gálvez, Isabel | Fioravanti, Antonella | Ortega, Eduardo
Balneotherapy (BT) is one of the most commonly used non-pharmacologic complementary therapies for different rheumatic diseases. Its beneficial properties probably derived from a combination of mechanical, thermal, and chemical effects, but the exact mechanism of action is not elucidated. This review aimed at summarizing the current knowledge about the effects of BT, and identifying its possible mechanism of action in different rheumatic diseases. Pubmed and Scopus were used to perform a search of the literature to extract articles including terms related to BT and rheumatic diseases published in the period from 2010 to 2021. We selected pre-clinical studies, randomized controlled trials, and clinical trials. The results of clinical studies confirmed the beneficial properties on different mediators and factors of inflammation, oxidative stress, cartilage metabolism, and humoral and cellular immune responses in patients affected by chronic degenerative musculoskeletal disorders. The data derived from OA and RA-induced murine models revealed the efficacy of different BT treatments in decreasing pain, inflammation, and improving mobility, as well as in reducing the expression of matrix-degrading enzymes and markers of oxidative stress damage. Different in vitro studies analyzed the potential effect of a mineral water, as a whole, or of a mineral element, demonstrating their anti-inflammatory, antioxidant, and chondroprotective properties in OA cartilage, synoviocytes and chondrocytes, and osteoblast and osteoclast cultures. The presented data are promising and confirm BT as an effective complementary approach in the management of several low-grade inflammation, degenerative, and stress-related pathologies, as rheumatic diseases.
Afficher plus [+] Moins [-]Hydrochemical characteristics and groundwater quality in the thick loess deposits of China Texte intégral
2022
Li, Shujian | Su, He | Li, Zhi
Water quality and quantity should be paid more attention in regions with arid climate and thick vadose zones since the limited groundwater cannot be replenished rapidly once polluted. This study focused on the Loess Plateau of China to investigate the geochemical mechanism affecting groundwater chemistry and to calculate contribution rates of multiple sources to groundwater solutes. We employed multiple methods (diagrams, bivariate analyses, hierarchical cluster analysis (HCA), sodium adsorption ratio (SAR), water quality index (WQI), correlation analysis, and forward model) for the above purposes. We collected 64 groundwater samples in the thick loess deposits in June 2018 (flood season) and April 2019 (dry season). The average concentrations of cation were in the order of Ca²⁺ > Na⁺ > Mg²⁺ > K⁺ in the flood season, and Na⁺ > Ca²⁺ > Mg²⁺ > K⁺ in the dry season. The order of anions contents in the flood season and the dry season were HCO₃⁻ > SO₄²⁻ > Cl⁻ > NO₃⁻. The major hydrochemical facies were Ca-HCO₃ and Ca·Mg-HCO₃ in the flood season and Na·Ca-HCO₃·SO₄ and Na-HCO₃ in the dry season, respectively. Most of the groundwater (95% in the flood season and 96% in the dry season) was suitable for drinking, and the overall water quality was acceptable for irrigation. Mineral dissolution and cation exchange were important natural processes affecting groundwater chemistry. The forward model showed that the contribution of atmospheric input, anthropogenic input, evaporite dissolution, silicate weathering, and carbonate weathering to solutes in groundwater was 2.3±1.5%, 5.0±7.1%, 19.3±21.4%, 42.8±27.3%, and 30.6±27.1% in the flood season, and 9.1±6.4%, 3.4±5.2%, 20.3±15.9, 56.6±23.2%, and 10.7±15.4% in the dry season, respectively. Obviously, silicate and carbonate weathering contribute the most to groundwater chemistry in the flood season, while silicate weathering and evaporite dissolution contribute the most in the dry season. Although the overall contribution of anthropogenic inputs was insignificant, it was the dominant source of solutes for local groundwater. This study provides fundamental information for water management in arid areas.
Afficher plus [+] Moins [-]Characteristics of extracellular organic matters and the formation potential of disinfection by-products during the growth phases of M. aeruginosa and Synedra sp Texte intégral
2022
Yao, Juanjuan | Zhao, Meng | Song, Lili | Chen, Xiangyu | Zhang, Zhi | Gao, Naiyun
Extracellular organic matter (EOM) is an important precursor of disinfection by-products (DBPs). Nowadays, little is known about changes in molecular weight (MW) and hydrophilic (HPI)/hydrophobic (HPO) fractions of EOM during the entire algal growth phase. In this study, a combined approach of fractionation procedure and parallel factor (PARAFAC) analysis was applied to characterize the EOM during the entire growth phase of two algal species (M. aeruginosa and Synedra sp.), and investigated the relationships between fluorescent component and the DBP formation potential (FP) in MW and HPI/HPO fractions. Thereinto, three components (including one protein-like component (C1), one humic-like component (C2), and one fulvic acid–like component (C3)) were identified by the PARAFAC model. For two algae, the HPI and high MW (> 100 kDa) fractions were both the main components of algal EOM in the three growth phases in terms of the dissolved organic carbon. The high MW fraction had more C1 compared with other MW fractions, especially for M. aeruginosa. Besides, the formation risk of EOM-derived DBPs from M. aeruginosa was lower than that from Synedra sp. The result of this study showed the FP of DBPs varied with fluorescent components of algal EOM fractions and also indicated that the humic-like substances were tended to form trichloromethane and the tryptophan-like substances were associated with dichloroacetic acid by canonical correspondence analysis for both two algae.
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