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Association of PM2.5 and its components with lengths of hospital stay for hand foot and mouth disease in children Texto completo
2022
Li, Wei | Wang, Jieguo | Zhou, Kai | Tian, Ye | Wei, Feiran | Zhang, Mingzhi | Wang, Xu
Hand foot and mouth disease (HFMD) is a widespread public health concern but the studies on air pollution and the lengths of hospital stay (LOS) of HFMD are scarce nevertheless. Clinic demographic features among 5135 hospitalized HFMD cases in Nanjing, China, had been characterized from 2012 to 2017. Then, we had analyzed the association between PM₂.₅ short-term exposure as well as its components (OM, BC, SO4²–, NH4⁺, NIT, SOIL, and SS) and the LOS of HFMD. Among these cases that were involved in our study, 98.62% were aged 0–6 years old, and 3772 (73.46%) were hospitalized within 1 week or less. The LOS of HFMD patients was different in various age ranges, illness onset years, and illness onset seasons (P < 0.01). For per IQR increase in PM₂.₅ concentrations, LOS of HFMD increased by 0.52 (0.33, 0.71), 0.50 (95% CI, 0.31–0.69) and 0.46 (95% CI, 0.28–0.65) day in adjusted models at lag 3 days, lag 7 days, and lag 14 days, respectively. In addition, per IQR increase of BC, SO₄²⁻, NH₄⁺, NIT, and SOIL was also significantly associated with the LOS of HFMD. Our findings corroborated that short-term PM₂.₅ exposure was associated with the increased LOS of HFMD, and its components (BC, SO₄²⁻, NH₄⁺, NIT, and SOIL) of PM₂.₅ might play a key role in prolonged LOS of HFMD.
Mostrar más [+] Menos [-]Feasibilty of valorizing quarry wastes in the synthesis of geopolymer binders: engineering performances and microstructure Texto completo
2022
Nemaleu, Juvenal Giogetti Deutou | Belela, Elodie Awam | Nana, Achille | Kaze, Rodrigue Cyriaque | Venyite, Paul | Yanou, Rachel Nkwaju | Djobo, Jean Noel Yankwa | Kamseu, Elie
The exploitation of volcanic rock quarries generates enormous waste, which causes the problem of disposal, leading to rising dust levels in quarries and depositions on nearby farms by runoffs. To address this issue, the development of sustainable solution for their valorization in construction industries is required. The present investigation aims to valorize granite (GW) and basalt (BW) quarry waste powders as partial replacement (up to 20 wt.%) of iron-rich aluminosilicates in the synthesis of geopolymer binders. Both synthesized series of samples were sealed and cured at 7, 14, and 28 days at room temperature before subjecting to various analytical techniques, including the mechanical properties, XRD, FT-IR, TG/DTG, and SEM–EDS. The results showed that both GW and BW powders are efficient to produce sufficient amounts of geopolymer binder, with ensure good cohesion and connectivity between different components within the final matrices. The values of compressive strength were 7.5–35.9 MPa and 6.2–39.7 MPa for laterite/granite and laterite/basalt geopolymer composites, denoted LGA and LBA, respectively. Moreover, the coexistence of the amorphous Na-aluminosilicate, Ca-aluminosilicate, and Na-polyferrosialate species is responsible for the mechanical properties development of the end-products. Based on the findings, the selected quarry wastes appeared to be sustainable and cost-effective materials for the synthesis of low-energy consumption binder, suitable for the production of construction materials.
Mostrar más [+] Menos [-]Impact of financial inclusion and globalization on environmental quality: evidence from G20 economies Texto completo
2022
Tian, Yuan | Li, Luxi
Sustainable development and addressing climate change are among the most pressing issues faced by countries around the world. This research investigates the dynamic associations between financial inclusion, globalization and CO₂ emissions of G20 nations from 2005 to 2018, considering the effects of industrial structure, corruption, green energy utilization and economic growth as control variables. In this study, both financial inclusion and globalization index were measured using principal component analysis (PCA). This study examines long-term associations using cross-sectional augmented autoregressive distributed lag (CS-ARDL) technique that offers more accurate outcomes. In addition, the VECM Granger causality method was applied to find causal relationships between study variables. Findings show that in financial inclusion, globalization has positive significant effect on carbon emissions. Moreover, corruption and economic have positive impact on carbon emissions, and renewable energy shows negative impact on environmental quality. The findings of this research are critical for achieving sustainable development and pollution control goals. Governments need to work to bring into line the financial inclusion goals with renewable energy consumption habits and environmental strategies.
Mostrar más [+] Menos [-]An ecotoxicological approach can complement the assessment of natural waters from Portuguese reservoirs? Texto completo
2022
Rodrigues, Sara | Pinto, Ivo | Martins, Fábio | Formigo, Nuno | Antunes, Sara Cristina
Within the scope of the European Water Framework Directive (WFD), the scientific community recognized clear opportunities to take advantage of the use of ecotoxicological tools in water quality assessments. In this perspective, bioassays and biomarkers were suggested to contribute to the integration of the chemical and biological conditions, and thus to provide an overall insight into the quality of a water body. This study aimed to assess whether current bioassays as feeding rate assays with Daphnia longispina and growth inhibition assays with Lemna minor are suitable to detect potential ecotoxicity, using waters from Portuguese reservoirs. Several sampling sites were defined in reservoirs (Miranda, Pocinho, and Alqueva). The samplings were conducted in autumn of 2018 and spring of 2019. Total chlorophyll, lipid peroxidation, and proline content were also evaluated in L. minor. Results demonstrated that D. longispina showed some sensitivity to water treatments; however, the results were difficult to interpret since no reason or trend can be accurate. All parameters of L. minor did not show sensitivity to detect potential ecotoxicological risks associated with natural water understudy, since no discrimination among the water treatments was recorded. However, biomarkers/bioassays proved to be concordant to each other. Under the conditions evaluated here (reservoirs and sampling periods), the biological responses observed were not consistent, clear, and coherent with the physical–chemical parameters and chemical analyses performed, suggesting that the ecotoxicological tools selected were not sensitive to assess water quality in this type of ecosystems. In this sense, species of different trophic levels are recommended for ecotoxicological analyses due to differences in species sensitivities.
Mostrar más [+] Menos [-]Wavelet and Fourier augmented convergence analysis of methane emissions in more than two centuries: implications for environmental management in OECD countries Texto completo
2022
Solarin, Sakiru Adebola | Erdogan, Sinan | Okumus, Ilyas
Addressing the challenges posed by pollutants is necessary to achieve Sustainable Development Goal 13, which involves climate change mitigation and enhancement of environmental quality. The convergence analysis of a pollutant provides information that can be useful to how to handle that pollutant across countries or regions, and previous studies mainly focused on carbon emission. However, the second most significant greenhouse gas, methane emission, was mostly ignored. The primary objective of this research is to investigate whether stochastic convergence of methane emissions is valid in 37 OECD (Organisation for Economic Co-operation and Development) countries using a dataset of more than two centuries. The results obtained by using a set of traditional unit root tests and a newly proposed wavelet unit root test with a Fourier function provide overwhelming evidence for these countries’ divergence of methane emissions. The policy implications resulting from the empirical findings for environmental management are discussed in the relevant sections of the paper.
Mostrar más [+] Menos [-]Preparation and evaluation of humic acid–based composite dust suppressant for coal storage and transportation Texto completo
2022
Yu, Xiaoxiao | Hu, Xiangming | Cheng, Weimin | Zhao, Yanyun | Shao, Zhiang | Xue, Di | Wu, Mingyue
To mitigate environmental pollution caused by the escape of dust during coal storage and transportation, humic acid (HA) and grafted acrylamide (AM) were used as raw materials to prepare a composite dust suppressant suitable for coal storage and transportation. Single-factor experiments were used to explore the optimal synthesis conditions of the dust suppressant, and the microstructure of the product was studied using Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (¹H-NMR), scanning electron microscopy (SEM), and other methods. The wetting effect of the dust suppressant on coal was also investigated by way of molecular dynamics (MD) simulations. The experimental results showed that the dust suppressant had good wind erosion resistance (wind erosion rate 10.2%), shock resistance (loss rate 3.63%), and anti-evaporation performance, while the MD simulation and permeability analysis results showed that the dust suppressant had an excellent wetting effect on the coal surface. SEM images revealed that the dust suppressant can fill the gaps between coal dust particles and bond them together to form a consolidated layer, thereby effectively inhibiting the escape of dust sources during coal storage and transportation.
Mostrar más [+] Menos [-]Radon exposure and risk of cerebrovascular disease: a systematic review and meta-analysis in occupational and general population studies Texto completo
2022
Lü, Liping | Zhang, Yijia | Chen, Cheng | Field, Robert William | Kahe, Ka
Although it is biologically plausible, findings relating radon exposure to the risk of cerebrovascular disease (CeVD) are inconsistent and inconclusive. To investigate whether radon exposure was associated with the risk of CeVD, we qualitatively and quantitatively summarized the literature on radon and CeVD in both occupational and general populations. A search of PubMed, Embase, Scopus, and Web of Science was performed for peer-reviewed articles published through March 2022. Studies were excluded if radon exposure was not assessed separately from other ionizing radiation. In the meta-analysis, excess relative risks (ERRs) were converted to relative risks (RRs), and the pooled RRs and 95% confidence intervals (CIs) were determined using the random-effects model (DerSimonian and Laird). In the systematic review, nine eligible studies were summarized. Six occupational studies indicated inconsistent associations between cumulative radon exposure and CeVD mortality among mine workers. With available data from four updated occupational studies (99,730 mine workers and 2745 deaths), the pooled RR of radon exposure with CeVD mortality showed a non-significant association (1.10, 95% CI 0.92, 1.31). Three studies (841,270 individuals and 24,288 events) conducted in general populations consistently demonstrated a significant inverse relationship between residential radon exposure and risk of CeVD. The existing literature suggested a potential link between radon exposure and CeVD risk in general population. The inconsistent association in occupationally exposed populations may be explained by different methods of radon assessment and other methodological issues. Since radon exposure is a common public health issue, more rigorously designed epidemiologic studies, especially in the general population are warranted.
Mostrar más [+] Menos [-]A rapid evidence assessment of the potential risk to the environment presented by active ingredients in the UK’s most commonly sold companion animal parasiticides Texto completo
2022
Wells, Clodagh | Collins, C. M Tilly
A number of parasiticides are commercially available as companion animal treatments to protect against parasite infestation and are sold in large volumes. These treatments are not intended to enter the wider environment but may be washed off or excreted by treated animals and have ecotoxic impacts. A systematic literature review was conducted to identify the existing evidence for the toxicity of the six most used parasiticides in the UK: imidacloprid, fipronil, fluralaner, afoxolaner, selamectin, and flumethrin. A total of 17,207 published articles were screened, with 690 included in the final evidence synthesis. All parasiticides displayed higher toxicity towards invertebrates than vertebrates, enabling their use as companion animal treatments. Extensive evidence exists of ecotoxicity for imidacloprid and fipronil, but this focuses on exposure via agricultural use and is not representative of environmental exposure that results from use in companion animal treatments, especially in urban greenspace. Little to no evidence exists for the ecotoxicity of the remaining parasiticides. Despite heavy usage, there is currently insufficient evidence to understand the environmental risk posed by these veterinary treatments and further studies are urgently needed to quantify the levels and characterise the routes of environmental exposure, as well as identifying any resulting environmental harm.
Mostrar más [+] Menos [-]An analysis of the dye-sensitized solar cells fabricated with the dyes extracted from the leaves and flowers of Amaranthus cruentus Texto completo
2022
Sankaranarayanan, Sowmya | Kathiravan, Inbarajan | Balasundaram, Janarthanan | Shkir, Mohd | AlFaify, Salem
Dye-sensitized solar cells (DSSCs) were devised with the sensitizers prepared from the leaves and flowers of Amaranthus cruentus. Fresh and dried leaves were employed for extracting the dye sensitizers. Acetone, ethanol, and deionized water were used as solvents for the extraction process. A sum of nine dyes was prepared. For all the extracted dyes, spectroscopic studies (UV–visible & FTIR) were performed to ensure that the dyes are suitable to be used as sensitizers for DSSC. XRD and SEM were recorded for the TiO₂ paste used. Nine DSSCs were fabricated with the extracted dyes as sensitizers, TiO₂ as semiconductor oxide, I⁻/I³⁻ as electrolyte, and graphene-coated FTO as counter electrode. J-V characterization study was done for each cell showed that the cell with dye taken from the fresh leaves using acetone exhibited the highest efficiency of 0.816%. It was noted that these cells recorded higher efficiency than the previously reported works with dyes taken from Amaranthus red.
Mostrar más [+] Menos [-]Impact of globalization, institutional quality, economic growth, electricity and renewable energy consumption on Carbon Dioxide Emission in OECD countries Texto completo
2022
Cao, Huimin | Khan, Muhammad Kamran | Rehman, Abdul | Dagar, Vishal | Oryani, Bahareh | Tanveer, Arifa
This research for the first time examines the influence of the financial development, stock market, globalization, institutional quality, economic growth, electricity, and renewable energy consumption on carbon dioxide emission from 1985 to 2018 in thirty-six (OECD) countries. Cointegrations exist in the used variables based on the examined findings of the Kao, Westerlund, and Pedroni cointegration. Findings of the pooled mean group (PMG) indicate that renewable energy consumption, globalization, and institutional quality assist to reduce the carbon dioxide emission that improve the environment while financial development, stock market, electricity consumption, and economic growth cause to increase the carbon dioxide emission in OECD countries both in the long and in the short run. To reduce carbon dioxide emission, important policy implications are suggested for OECD countries.
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