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Measuring the urban land use efficiency of three urban agglomerations in China under carbon emissions 全文
2022
On the basis of DMSP/OLS and NPP-VIIRS night light images, this study realized carbon emission estimations based on the municipal level from 1999 to 2017, compensating for the characteristics of incomplete statistical data and different statistical calibers. On this basis, the epsilon-based measure (EBM) super-efficiency model and the global Malmquist–Luenberger (GML) index are used to measure the urban land use efficiency (ULUE) and urban land total factor productivity (ULTFP) of the three urban agglomerations under the carbon emission constraints from 1999 to 2017. The following conclusions are drawn through research. (1) The correlation coefficient between the total value of night light pixels and energy consumption carbon emissions was relatively high in the three major urban agglomerations during 1999–2017, and they all passed the significance test of 1%. (2) The ULUE of the three major urban agglomerations generally shows a downward trend and then an upward trend, and spatial heterogeneity is obvious. The spatial distribution of the average level of ULUE is Pearl River Delta Urban Agglomeration (PRDUA) > Yangtze River Delta Urban agglomeration (YRDUA) > Beijing–Tianjin–Hebei Urban agglomeration (BTHUA). (3) The ULTFP of the three major urban agglomerations are all showing an increasing trend, but the geometric mean of URTFP in the PRDUA, BTHUA, and YRDUA decreases successively. Technological progress is the main driving force to promote the progress of ULTFP in each urban agglomeration. (4) The kernel density estimation shows a significant gap in ULUE between the three major urban agglomerations in China, and a phenomenon of polarization or multipolarization is observed. The main reason is the hysteresis of technology diffusion.
显示更多 [+] 显示较少 [-]Electrocardiographic and histopathological characterizations of diabetic cardiomyopathy in rats 全文
2022
Diabetes is a clinical condition that is associated with insulin deficiency and hyperglycemia. Cardiomyopathy, retinopathy, neuropathy, and nephropathy are well known complications of the elevated blood glucose. Diabetic cardiomyopathy is a clinical disorder that is associated with systolic and diastolic dysfunction along with cardiac fibrosis, inflammation, and elevated oxidative stress. In this study, diabetes was induced by intraperitoneal injection of streptozotocin (STZ) 50 mg/kg. We determined the plasma levels of cardiac troponin-T (cTnT) and creatinine kinase MB (CK-MB) by ELISA. Diabetic rats showed abnormal cardiac architecture and increased collagen production. Significant elevation in ST-segment, prolonged QRS, and QT-intervals and increased ventricular rate were detected. Additionally, diabetic rats showed a prolongation in P wave duration and atrial tachyarrhythmia was observed. Plasma levels of cTnT and CK-MB were elevated. In conclusion, these electrocardiographic changes (elevated ST-segment, prolonged QT interval, and QRS complex, and increased heart rate) along with histopathological changes and increased collagen formation could be markers for the development of diabetic cardiomyopathy in rats.
显示更多 [+] 显示较少 [-]Occurrence and spread of antibiotic-resistant bacteria on animal farms and in their vicinity in Poland and Ukraine—review 全文
2022
Intensive animal farming emits to the environment very high concentrations of bioaerosol, mainly composed of microorganisms, including antibiotics resistant strains, and their derivatives. Poland is a significant producer of poultry and swine in Europe; Ukraine is located in the immediate vicinity of Poland and the EU. Thus, the review focuses on the presence of potentially pathogenic and antimicrobial-resistant zoonotic bacteria and antimicrobial genes in the environment of farms and food of animal origin in Poland and Ukraine. Existing data confirms presence of these bacteria in the food animal origin chain environment in both countries. However, it is difficult to compare the scale of multidrug-resistant bacteria (e.g. MRSA, ESBL) dissemination in Poland and Ukraine with other EU countries due to lack of more extensive studies and large-scale monitoring in these two countries. A series of studies concerning resistance of pathogenic bacteria isolated from livestock environment have been published in Poland but usually on single farms with a very limited number of samples, and without a genotypic drug resistance marking. From Ukraine are available only few reports, but also disturbing. The risk of antibiotic-resistant bacteria transmission does not only concern animal farming, but also other facilities of animal origin food supply chains, especially slaughterhouses.
显示更多 [+] 显示较少 [-]Genotoxic and mutagenic effects of chlorothalonil on the estuarine fish Micropogonias furnieri (Desmarest, 1823) 全文
2022
Chlorothalonil is a fungicide widely used in agriculture as well as an active ingredient in antifouling paints. Although it causes toxic effects on non-target organisms and can accumulate in fish tissues, little is known about its sublethal effects. Thus, genotoxic and mutagenic effects of intraperitoneal injected chlorothalonil in Micropogonias furnieri, an estuarine fish of frequent human consumption and a promising test-organism for ecotoxicological assays, were assessed. Chlorothalonil showed to be genotoxic (DNA damage by comet assay) and mutagenic (micronuclei, nuclear buds, apoptotic fragments, and bilobed cells) even at the lowest dose tested (0.35 μg g⁻¹) and in a dose-dependent manner (0.35 and 3.5 μg g⁻¹) for micronuclei, apoptotic fragments, and bilobed cells. As genomic instability may lead to carcinogenesis, the present evidence can assist decision-makers in banning this compound since any benefit toward food production is outweighed by the hazard to aquatic ecosystems and human health.
显示更多 [+] 显示较少 [-]Association between exposure to ambient air pollution and semen quality in adults: a meta-analysis 全文
2022
Air pollution has become a global concern and may be hazardous to human reproductive capacity, but the impact of exposure to air pollutants on semen quality remains controversial. We performed the meta-analysis to examine the association between air pollution exposure and semen quality. We searched PubMed, Web of Science Core Collection, and Cochrane Library databases (before December 2019). We selected original epidemiological studies on humans, written and published in English, that provided quantitative information to determine the associations between air pollution and sperm parameters. A random-effects model was used when the pooled effect estimates were found to be heterogeneous (I² > 50% or P < 0.05), otherwise, a fixed-effects model was applied. Publication bias was not evaluated for less than 10 included articles. Our meta-analysis showed that the standardised mean differences (SMDs) (95% confidence interval, 95% CI) of sperm concentration, sperm count, and sperm total motility were −0.17 (−0.20, −0.13), −0.05 (−0.08, −0.02), and −0.33 (−0.54, −0.11), respectively. However, exposure to air pollution was not related to sperm progressive motility (SMD = 0.00, 95% CI: −0.13, 0.12). The results indicated that exposure to air pollutants at a higher level was associated with impaired semen quality, including declined sperm concentration, reduced sperm count, and declined total motility. The results suggested that high level of air pollution exposure had a negative effect on semen quality. Improvement of air quality is important for enhancing semen quality.
显示更多 [+] 显示较少 [-]Impact of market constraints on the development of small-scale biogas technology in Sub-Saharan Africa: a systematic review 全文
2022
The sustainable production and use of small-scale biogas energy are required to ensure clean household energy access in developing countries, including the Sub-Saharan Africa (SSA) region. This is influenced by market risks, which can be identified as political, economic, social, technical, legal, and environmental (PESTLE). This study examines peer-reviewed and grey literature for the period from 2000 to 2020 to identify the PESTLE constraints and assess their impact on the sustainable development of the technology in the SSA region. The production of biogas with small-scale plants is commonly done by rural and peri-urban households. Results show that economic constraints are the most dominant and reducing at a slow pace. This is followed by political constraints, which have received much attention in the last two decades. Despite the policy improvements, broader national bioenergy policies and interventions are still to make significant gains, especially in the Central African region. In order of significance, the Southern, East, and West Africa regions have made greater progress in reducing the constraints. To achieve the sustainable development of the technology, there is a need to further address the PESTLE constraints at national and regional levels. This study partly deduces that the unsustainable production, use, and inadequate regulation of the small-scale biogas sector are delaying its transition in the SSA region.
显示更多 [+] 显示较少 [-]Multiple heavy metal immobilization and strength improvement of contaminated soil using bio-mediated calcite precipitation technique 全文
2022
Sharma, Meghna | Satyam, Neelima | Reddy, Krishna R. | Chrysochoou, Maria
Bio-mediated calcite precipitation potential for multiple heavy metal immobilization in contaminated soils at industrial, waste dump, abandoned mine, and landfill sites is not explored yet. This study includes investigation of bio-mediated calcite precipitation for strength improvement and immobilization of heavy metals, specifically lead (Pb), zinc (Zn), and hexavalent chromium (Cr(VI)), in contaminated soils. Firstly, the toxicity resistance of bacteria against different concentrations (1000, 2000, 3000, 4000, and 5000 mg/l) of each heavy metals was investigated and observed that Pb and Cr were less toxic to Sporosarcina pasteurii than Zn. The poorly graded sand was spiked with 333–2000 mg/kg concentrations of a selected individual or mixed metal solutions, i.e., 1000 mg/kg and 2000 mg/kg individual concentrations of Pb, Zn, and Cr(VI); 500 mg/kg and 1000 mg/kg concentration of each metal in “Pb and Zn,” “Pb and Cr(VI),” and “Zn and Cr(VI)” mixture of heavy metals; and 333 mg/kg and 666 mg/kg concentration of each metal in “Pb, Zn, and Cr(VI)” mixed metal concentration. Contaminated soil was biotreated with Sporosarcina pasteurii and cementation (a solution of urea and calcium chloride dihydrate) solutions for 18 days. Biocemented sand specimens were subjected to testing of hydraulic conductivity, ultrasonic pulse velocity (UPV), unconfined compressive strength (UCS), calcite content, pH, toxicity characteristic leaching procedure (TCLP), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The heavy metal contaminated samples showed decrease in hydraulic conductivity and increase in UPV and UCS after biotreatment; however, the changes in engineering properties were found more moderate than clean biocemented sand. The conversion of Cr(VI) to Cr(III) followed by Cr₂O₃ precipitation in calcite lattice was observed. Zn was precipitated as smithsonite (ZnCO₃), while no Pb precipitate was identified in XRD results. TCLP leaching showed Pb and Cr immobilized proportional to calcite precipitated amount, and higher calcite amounts yielded levels within regulatory limits. Pb and Cr(VI) immobilization up to 92 % and 94 % was achieved, respectively, in contaminated biocemented sand. Zn was found completely leachable as smithsonite is only stable down to pH~5, and strongly acidic TCLP solution reversed all immobilization at natural soil pH~8–9.
显示更多 [+] 显示较少 [-]Derivation of water quality criteria for glyphosate and its formulations to protect aquatic life in China 全文
2022
Van Wright, Cornelius | Zhang, Kaibo | Zhang, Ruiqing | Guo, Guanghui | Li, Huixian | Bai, Yingchen | Lin, Ying | Cai, Ting
Extensive use of the herbicide glyphosate leads to a high detection rate in the environment and potential risks to nontarget aquatic life. China ranks first globally in the production and consumption of glyphosate, but there are no glyphosate water quality criteria (WQCs) for protecting aquatic life. Here, data on the acute and chronic toxicity of glyphosate and glyphosate-based formulations (GBFs) to freshwater aquatic life were collected and screened. Significant differences in species sensitivity distributions (SSDs) and toxicity values for acute or chronic toxicity were found between glyphosate and GBFs. The hazardous concentrations for 5% of species (HC₅) of glyphosate or GBFs between native and nonnative species were different, and native species were found to be more sensitive to the toxicity of glyphosate. The acute and chronic WQCs derived with the SSD method for glyphosate based on the toxicity data for native species in China were 3.35 and 0.26 mg/L, respectively, and those found for GBFs were 0.21 and 0.005 mg/L, respectively. The WQCs in this study were quite different from those estimated using similar statistical extrapolation methods in other countries, which reflects the differences in species sensitivity to glyphosate toxicity in different regions. The hazard quotients (HQs) were calculated based on the WQCs and concentrations of glyphosate in some surface waters in China and indicated that glyphosate exhibits medium or high hazard risk in some samples of Tai Lake, surface water in Guiyang, fishpond water in Chongqing, rural drinking water, and surface water and reservoir water in Henan Province. The WQCs of glyphosate and GBFs have scientific significance for the exposure and pollution control of herbicide formulations and the protection of aquatic life in China.
显示更多 [+] 显示较少 [-]The mutagenic effect of tobacco smoke on male fertility 全文
2022
Omolaoye, Temidayo S. | El Shahawy, Omar | Skosana, Bongekile T. | Boillat, Thomas | Loney, Tom | Du Plessis, Stefan S.
Despite the association between tobacco use and the harmful effects on general health as well as male fertility parameters, smoking remains globally prevalent. The main content of tobacco smoke is nicotine and its metabolite cotinine. These compounds can pass the blood-testis barrier, which subsequently causes harm of diverse degree to the germ cells. Although controversial, smoking has been shown to cause not only a decrease in sperm motility, sperm concentration, and an increase in abnormal sperm morphology, but also genetic and epigenetic aberrations in spermatozoa. Both animal and human studies have highlighted the occurrence of sperm DNA-strand breaks (fragmentation), genome instability, genetic mutations, and the presence of aneuploids in the germline of animals and men exposed to tobacco smoke. The question to be asked at this point is, if smoking has the potential to cause all these genetic aberrations, what is the extent of damage? Hence, this review aimed to provide evidence that smoking has a mutagenic effect on sperm and how this subsequently affects male fertility. Additionally, the role of tobacco smoke as an aneugen will be explored. We furthermore aim to incorporate the epidemiological aspects of the aforementioned and provide a holistic approach to the topic.
显示更多 [+] 显示较少 [-]Environmental and occupational exposure of metals and female reproductive health 全文
2022
Dutta, Sulagna | Gorain, Bapi | Choudhury, Hira | Roychoudhury, Shubhadeep | Sengupta, Pallav
Untainted environment promotes health, but the last few decades experienced steep upsurge in environmental contaminants posing detrimental physiological impact. The responsible factors mainly include the exponential growth of human population, havoc rise in industrialization, poorly planned urbanization, and slapdash environment management. Environmental degradation can increase the likelihood of human exposure to heavy metals, resulting in health consequences such as reproductive problems. As a result, research into metal-induced causes of reproductive impairment at the genetic, epigenetic, and biochemical levels must be strengthened further. These metals impact upon the female reproduction at all strata of its regulation and functions, be it development, maturation, or endocrine functions, and are linked to an increase in the causes of infertility in women. Chronic exposures to the heavy metals may lead to breast cancer, endometriosis, endometrial cancer, menstrual disorders, and spontaneous abortions, as well as pre-term deliveries, stillbirths. For example, endometriosis, endometrial cancer, and spontaneous abortions are all caused by the metalloestrogen cadmium (Cd); lead (Pb) levels over a certain threshold can cause spontaneous abortion and have a teratogenic impact; toxic amounts of mercury (Hg) have an influence on the menstrual cycle, which can lead to infertility. Impact of environmental exposure to heavy metals on female fertility is therefore a well-known fact. Thus, the underlying mechanisms must be explained and periodically updated, given the growing evidence on the influence of increasing environmental heavy metal load on female fertility. The purpose of this review is to give a concise overview of how heavy metal affects female reproductive health.
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