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Monitoring bio-optical response of coastal waters surrounding the Indian subcontinent to atmospheric dust deposition using satellite data Full text
2020
Tyagi, Geetika | Babu, KN | Solanki, Hitesh Arvindbhai
The paper investigates the impact of atmospheric dust deposition on ocean biological productivity in association with oceanic supply of nutrients over specific regions of the Arabian Sea (20°N, 69°E) and the Bay of Bengal (20°N, 87°E) during wintertime (November–March) from the year 2012 to 2017 using satellite-based observations. During winter, selected regions are characterized by higher Chlorophyll-a (Chl-a) and major oceanic vertical supply of nutrients. Moderate Resolution Imaging Spectroradiometer onboard Aqua space-platform is used to obtain Chl-a and aerosol optical depth (AOD) data. Blended Chl-a daily product from various satellite sensors is also used. There are a total of nine cases (seven cases of the Arabian Sea region and two cases of the Bay of Bengal region) where episodic Chl-a enhancements following high AOD values are observed. Chl-a maxima lag behind AOD maxima by 1 to 4 days. Modern-Era Retrospective analysis for Research and Applications (Version-2) is used for AOD and dust deposition flux estimation. Estimated dust deposition flux ranges between 0.44 and 27.68 mg m⁻² day⁻¹.
Show more [+] Less [-]Beyond the flow rate: the importance of thermal range, flow intensity, and distribution for water-efficient showers Full text
2020
Adeyeye, Kemi | She, Kaiming | Meireles, Inês
Studies show that user behaviours have not necessarily changed, despite the prevalence of water-efficient products in the market. One reason is because the technical emphasis for delivering the water use efficiency of products has focused on reducing the flow rate. Therefore, this study was undertaken to examine the physical parameters that define the technical efficiency of showerheads against the experiential performance (and therefore the satisfaction with the showerheads). These parameters were measured in a controlled laboratory environment and the findings were triangulated against user feedback from in-home trials. Synergies between the laboratory data and user feedback were found. Notably, it was found that water spray intensity, distribution, and temperature loss all impact the quality of showering experience. These factors also influence shower duration—and thus the volume of water used in the shower. Significantly, these technical metrics affected the overall experiential performance of such products from the users’ perspective. Therefore, the design of water-efficient showerheads, in addition to delivering water discharge savings, should avoid poor spray distribution, intensity, and heat retention. The implications of the findings are that water efficiency labelling and product standards should extend beyond the emphasis on limiting the flow rates—typically to 9 l per min for showerheads. This study shows good merit for including the spray intensity (pressure), distribution, and degree of heat loss, in addition to the discharge rate, as part of the performance and efficiency considerations of showerheads.
Show more [+] Less [-]A structurally integrated water environmental modeling system based on dual object structure Full text
2020
Wang, Peng | Wang, Chuanhai | Hua, Zulin | Wei, Yongping | Ma, Tengfei | Shen, Xia | Zeng, Xianmin | Liu, Xiaodong | He, Li | Tang, Hualei
The GIS-based water quantity and water quality model is widely used to provide decision-making supports for water resource and water quality management. However, the existing integration patterns of GIS and model system mainly depend on data communication between themselves which may lead to low operating efficiency and time-consuming model setup. In this paper, a generalized data structure (dual object structure (DOS)) which can store the data of GIS objects and model objects together is proposed and realized for the first time, avoiding frequent data communication during the period of numerical simulation and result expression, realizing the fusion of GIS objects and model objects at the data structure level, improving the operating efficiency of the system. Finally, the water quantity and water quality modeling software (digital basin simulation system (DBSS)) based on DOS was developed by using C++ language. The software has been applied successfully in large-scale river basins of China, and one of the cases was demonstrated to show the application process and the outstanding results.
Show more [+] Less [-]Innovative health risk assessments of heavy metals based on bioaccessibility due to the consumption of traditional animal medicines Full text
2020
Zuo, Tian-Tian | Qu, Hao-Ran | Jin, Hong-Yu | Zhang, Lei | Luo, Fei-Ya | Yu, Kun-Zi | Gao, Fei | Wang, Qi | Sun, Lei | He, Huai-Zhen | Ma, Shuang-Cheng
Few studies reported the extent of heavy metal accumulation in traditional Chinese medicines (TCMs). Currently, oral bioaccessibility of lead (Pb), cadmium (Cd), arsenic (As), mercury (Hg), and copper (Cu) present in traditional animal medicines was investigated with physiologically based extraction test–extracted in vitro model. We are the first to develop a health risk assessment strategy by combinational analysis of bioaccessible heavy metal levels to calculate target hazard quotient (THQ), target hazard index (THI) and cancer risk (CR), which has capacity to evaluate the heavy metal associated heath risk of traditional animal medicines. To precisely acquire a realistic risk assessment, questionnaire data was adopted to measure the frequency and duration of the exposure to traditional animal medicines, and the safety factor was highlighted as well. Our data revealed that the bioaccessibility of Hg was the lowest among the five heavy metals. After the adjustment with the bioaccessibility of each heavy metal to target hazard index (THI) values, excitingly, the results manifested that the consumption of traditional animal medicines might not exert an unacceptable health risk in a broad community. In addition, the CR values of As and Pb indicated that the risk of developing cancers was quite lower than their acceptable levels in the clinic.
Show more [+] Less [-]The impact of age-related sub-chronic exposure to chlorpyrifos on metabolic indexes in male rats Full text
2020
Samarghandian, Saeed | Foadoddin, Moshen | Zardast, Mahmoud | Mehrpour, Omid | Sadighara, Parisa | Roshanravan, Babak | Farkhondeh, Tahereh
Chlorpyrifos (CPF), an organophosphorus pesticide (OP), has been implicated in metabolic diseases; however, the data are controversial. Rising age has been found as a main risk factor for metabolic diseases, and it has been proposed that advanced age increases susceptibility to the toxic effects of OPs. Therefore, this investigation aimed to evaluate the impact of CPF on hyperglycemia, hypercholesterolemia, and inflammation in animals with different ages. CPF (5 mg/kg) for 45 consecutive days was administered orally to male Wistar rats with different ages including 2-, 10-, and 20-month-old. The results indicated an increase in glucose and inflammatory indices, and also lipid profile was changed in the serum of aged animals in comparison with the 2-month-old animals. CPF administration amplified these parameters in the 20-month-old rats in comparison with that of aged-matched controls. The histopathological examination also indicated that CPF caused slight to moderate changes in the liver of 2-, 10-, and 20-month-old animals. Cholestasis was also observed in the CPF-administrated 20-month-old rats. In conclusion, aging may increase the susceptibility to CPF-induced metabolic disturbances in the animal models. It is proposed that advancing in age elevates the susceptibility to the metabolic effects of CPF.
Show more [+] Less [-]Feasibility study on the utilization of coal mining waste for Portland clinker production Full text
2020
Malagón, Beatriz | Fernández, Gema | De Luis, Julio Manuel | Rodríguez, Rafael
Feasibility study on the utilization of coal mining waste for Portland clinker production Full text
2020
Malagón, Beatriz | Fernández, Gema | De Luis, Julio Manuel | Rodríguez, Rafael
CMWs (coal mine wastes) as the waste products of coal exploitation or washing plants are a source of pollution that generates waste management problems, especially those that are very old and without a known owner. CMW chemical composition indicates that it contains SiO₂-Al₂O₃-Fe₂O₃ in such percentages that it can be used in the production of Portland cement clinker, which can lead to potential savings in clinker production, not only in raw material but also in fuels if the CMW has a minimum calorific value and has not suffered self-combustion. After characterization of different CMWs from mining sites located in the north of Spain, six types of CMW have been selected and different raw meal formulations have been designed by software, maximizing the substitution rate of CMW and ensuring a correct raw meal chemical parameters. Along with a reference raw meal, all CMW clinkers were sintered, ground with gypsum, and tested determining the setting time, compressive strength, and soundness. The results of the physico-mechanical tests show that the mechanical performance of the CMW cements was consistent with the European requirements for a CEM Type I cement. CMW, especially those with a residual energetic content, can be utilized in clinker raw meal due to its availability in large quantities at low cost with the further significant benefits for waste management and environmental practices in mining and in cement production processes.
Show more [+] Less [-]Feasibility study on the utilization of coal mining waste for Portland clinker production
Biomarker and hematological fieldwork with amphibians: is it necessary to sample all night? Full text
2020
Brodeur, Julie Céline | Bahl, María Florencia | Natale, Guillermo Sebastián | Poliserpi, María Belén
Biomarker and hematological fieldwork with amphibians: is it necessary to sample all night? Full text
2020
Brodeur, Julie Céline | Bahl, María Florencia | Natale, Guillermo Sebastián | Poliserpi, María Belén
In the context of the global amphibian crisis, biomonitoring constitutes a valuable assessment tool to provide critical up to date information on the status and health of amphibians worldwide. The aim of the current study was to evaluate the possible confounding effects of sex, size, and time since capture on enzymatic biomarkers and hematologic parameters of the South American frog Leptodactylus latrans. Frogs were collected by hand between 9 pm and 12 am on two consecutive nights. On the first night, captured frogs were transported for 2 h by car to laboratory installations, maintained overnight in plastic containers, and blood and tissue sampled on the next morning. In contrast, frogs collected on the second night were blood and tissue sampled in the field, immediately after the capture period. Hematological parameters were analyzed, and enzymatic activities of catalase, cholinesterase (ChE), and glutathione S-transferase (GST) were determined in the plasma, liver, kidney, and muscle. A sex difference was observed only for total white blood cell counts (WBC), females exhibiting significantly greater values than males. The packed cell volume (PCV), mean corpuscular hemoglobin concentration (MCHC), WBC, and muscle ChE activity were significantly correlated with snout-vent length (SVL). The correlation was inversed in the case of MCHC, WBC, and muscle ChE, while the correlation was positive between PCV and SVL. Most examined parameters presented similar values when frogs were sampled at night following capture or the next morning. Total red blood cells (RBCs) count, and plasma enzymatic activities of ChE and GST were the only parameters that presented significantly increased values in morning samplings compared with night samplings. Overall, the current study indicates that it is best to sample the frogs as soon as possible after capture if hematologic or plasmatic biomarkers are examined. Nevertheless, it is possible to sample on the next morning if tissular biomarkers are employed.
Show more [+] Less [-]Biomarker and hematological fieldwork with amphibians: Is it necessary to sample all night?
Biomarker and hematological fieldwork with amphibians: is it necessary to sample all night?
Oral antimicrobial activity weakened in children with electronic waste lead exposure Full text
2020
Zhang, Shaocheng | Huo, Xia | Li, Minghui | Hou, Ruikun | Cong, Xiaowei | Xu, Xijin
Environmental lead (Pb) exposure can induce dysbacteriosis, impair oral health, and is associated with the development of dental caries. However, the mechanism is unclear. The aim of this study was to explore the effects of Pb toxicity on oral antimicrobial activity in children in an e-waste area. Results showed higher blood Pb levels in e-waste-exposed group children, accompanied by decreased saliva SAG (salivary agglutinin) concentrations, increased peripheral WBC (white blood cell) counts and monocyte counts, and elevated peripheral monocyte percentage. LnPb (natural logarithmic transformation of blood Pb level) was negatively correlated with saliva SAG concentration, while positively correlated with peripheral monocyte percentage. Saliva SAG concentration played a complete mediating role in the correlation of LnPb to peripheral monocyte percentage. To our knowledge, this is the first study on the relationship of environmental Pb exposure and oral antimicrobial activity in children, showing that environmental Pb exposure may weaken oral antimicrobial activity through reducing saliva SAG concentration, which may raise the risk of oral dysbacteriosis and ultimately pathogen infection.
Show more [+] Less [-]Assessing the spatiotemporal variation of NPP and its response to driving factors in Anhui province, China Full text
2020
Yang, Hongfei | Hu, Dandan | Xu, Hao | Zhong, Xuanning
Net primary productivity (NPP) of terrestrial ecosystems is an important metric of ecosystem functioning; however, the understanding of response mechanism of NPP to influencing factors and driving mechanisms are still limited. In this study, taking Anhui province as an example, spatio-temporal changes of NPP and its response to influencing factors were investigated for evaluating the effects of climate change and land use and land cover change (LUCC) on regional NPP. The Carnegie–Ames–Stanford Approach (CASA) model was employed for NPP simulation by using the MODIS normalized difference vegetation index (NDVI) data and meteorological data over 2001–2016. Combined domestic LUCC, the spatiotemporal distribution pattern and dynamic change characteristics of NPP under a long time series and its response to climate factors and human activities were analyzed in the Anhui province. The results indicated that from 2001 to 2016, total NPP had a fluctuated and decreased trend with the variation range between 30.52 and 38.07 TgC in Anhui province. The multi-year average of total NPP was about 34.62 TgC. The highest value was in 2008 and the lowest value was in 2011. Among them, amount of forestland NPP was the most. The spatial distribution of NPP shows that the high value area was mainly distributed in southern Anhui mountain areas and western Anhui Dabie mountain areas; the lower value was distributed in the middle in the study area. The area of which the NPP showed a slight decrease and essentially unchanged accounted for 59.35% and 31.82%, respectively. In general, the correlation between vegetation NPP and temperature was greater than that between precipitation. The vegetations NPP of eight land use types were all positively correlated with temperature. However, the other seven types of land use were negatively correlated with precipitation except cultivated land. In the past 16 years, the decrease of cultivated land areas and the increase of urban and construction land areas contributed a lot to the decrease of vegetation NPP in Anhui province. The NPP changes of different land use types were closely related to climatic factors, land cover area, and vegetation types.
Show more [+] Less [-]China’s power transition under the global 1.5 °C target: preliminary feasibility study and prospect Full text
2020
Xu, Yan | Yang, Kun | Yuan, Jiahai
Based on the 1.5 °C temperature control target of the Paris Agreement, the two scenarios in this paper which are 1.5 degree scenario (1.5DS) and 2 degree scenario (2DS) aim to analyze the CO₂ emission space and power transition path constrains of the power sector in China. This paper then discusses the possible scenarios of 1.5DS and 2DS power planning schemes in 2050. The conclusions are as follows: (1) China’s electricity consumption saturation period will occur during the period of 2030–2040; (2) Driven by technology learning, the levelized cost of electricity (LCOE) of wind power will have obvious competitive advantages in 2020 and so does solar power in 2030. However, due to the impact of additional grid connection costs of new energy power, economic advantages can only be obtained in the power market after at least 10 years; (3) The installed capacity of coal power in 1.5DS and 2DS will peak in 2020, and CO₂ emissions will also peak in 2020, then it shows a trend of decreasing year by year. However, it should be noted that 1.5DS is with possibilities, but with enormous challenges as the same time; (4) Accelerating the green and low carbon transition of power sector must be gradually improving the power market and electricity price mechanism, providing a good transition environment for the power sector, developing emerging power technology, and promoting multi-energy complementary systems.
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