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Long-term cadmium exposure affects cell adhesion and expression of cadherin in the male genital organ of Pardosa pseudoannulata (Bösenberg & Strand, 1906) Full text
2020
Lv, Bo | Wang, Juan | Peng, Yuande | Wang, Zhi | Song, Qisheng
Pardosa pseudoannulata (Araneae: Lycosidae), as an important predator of crop pests, has served as a strong driver for ecological regulation of pests. Cadmium (Cd) is a toxic heavy metal widely distributed in the soil in China, which not only seriously pollutes the ecological environment, but also poses a great threat to the survival of organisms. Palpal bulbs are the genital organs of male spiders, playing an important role in reproductive physiology. However, the effects of long-term Cd stress on the genital organ of the primary pest predator were poorly understood. Therefore, we investigated the Cd effect on the male palpal organ of P. pseudoannulata at morphological and gene expression levels. The results showed that no obvious difference in the morphology between the Cd-treated and control groups was observed, but cell adhesion was affected at molecular level. Transcriptome sequencing analysis revealed that under long-term Cd stress, the biological processes including cell-cell adhesion via plasma-membrane adhesion molecules, cell-cell adhesion, and homophilic cell adhesion via plasma membrane adhesion molecules were the top three differentially expressed terms (p-adj < 0.001), and 51 unigenes were annotated into cadherin-related proteins, such as protocadherin, cadherin-87A, and cadherin-96Ca, among which, 18 unigenes were significantly upregulated under the Cd stress. Our outcomes indicate that the differentially expressed genes involved in cell adhesion may explain the negative effects of Cd stress on the spider genital organ, and the comprehensive transcriptome dataset will also provide a profound molecular information of the genital organ of P. pseudoannulata.
Show more [+] Less [-]Towards sustainable system configuration for the treatment of fish processing wastewater using bioreactors Full text
2020
Mannacharaju, Mahesh | Kannan Villalan, Arivizhivendhan | Shenbagam, Buvaneswari | Karmegam, Patchai Murugan | Natarajan, Prabhakaran | Somasundaram, Swarnalatha | Arumugam, Gnanamani | Ganesan, Sekaran
The wastewater generated from fish processing industry contains a credible level of biodegradable proteins and low biodegradable fats, oils, and grease (FOG). The conventional biological treatment of fish processing wastewater (FPWW) containing high concentration of FOG faces the challenges of clogging, hindrance to sedimentation due to the formation of hydrophobic sludge along with lipids, flocculation of sludge with poor activity, dewatering of sludge due to the presence of lipids, and formation of aminated offensive odors. The present investigation employed baffled moving bed biofilm reactor (BMBBR), up-flow anaerobic sludge blanket (UASB) reactor, fluidized immobilized cell carbon oxidation (FICCO) reactor, and chemoautotrophic activated carbon oxidation (CAACO) reactors in series to treat FPWW. Five treatment options were evaluated to elevate the correct option for the treatment of FPWW. The treatment option V had established the removal efficiency of COD, 99 ± 0.1%; protein, 99 ± 0.2%; lipids, 100%; and oil and grease, 100%.
Show more [+] Less [-]Risk grade assessment of sudden water pollution based on analytic hierarchy process and fuzzy comprehensive evaluation Full text
2020
Zhang, Hao | Li, Wenjun | Miao, Pingping | Sun, Bowen | Kong, Fanqing
Sudden water pollution is a global environmental issue. On a large spatial scale, any pollution source may cause water pollution incidents. Dividing a large watershed into several units and giving each unit a different level would be favorable for managing sudden water pollution incidents. To scientifically divide an area into units and determine their risk grade of sudden water pollution, data of pollution sources were collected, and an area was divided into risk assessment units of sudden water pollution. The risk grade assessment was conducted following the analytic hierarchy process (AHP) and fuzzy comprehensive evaluation method. The technology combined with the AHP and fuzzy comprehensive evaluation (F-AHP) can generate the hydrology, pollution source, natural geography, and socioeconomic characteristics of each unit and provide a risk grade evaluation. A risk grade assessment was conducted using the Yongding River as a case study. The results show that the areas with high sudden water pollution risk were mainly distributed in Shanxi Datong and Hebei Zhangjiakou. Sufficient control of pollution sources in production processes and the establishment of necessary measures to strengthen inspections should reduce the risk of sudden water pollution.
Show more [+] Less [-]Study on the association between ambient air pollution and daily cardiovascular death in Hefei, China Full text
2020
Xu, Jixiang | Geng, Wenfeng | Geng, Xiya | Cui, LongJiang | Ding, Tao | Xiao, Changchun | Zhang, Junqing | Tang, Jing | Zhai, Jinxia
Cardiovascular disease has always been the most serious public health problem in China. Although many studies have found that the risk of death caused by cardiovascular disease is related to air pollutants, the existing results are still inconsistent. The aim of this study was to investigate the effects of air pollutants on the risk of daily cardiovascular deaths in Hefei, China. Daily data on cardiovascular deaths, daily air pollutants, and meteorological factors from 2007 to 2016 were collected in this study. A time-series study design using a distributed lag nonlinear model was employed to evaluate the association between air pollutants and cardiovascular deaths. First, a single air pollutant model was established based on the minimum value of Akaike information criterion (AIC), and the single day lag effects and multi-day lag effects were discussed separately. Then, two-pollutant models were fitted. Subgroup analyses were conducted by gender (male and female), age (< 65 age and ≥ 65 age), and disease type (ischemic heart disease and cerebral vascular disease). There were 34,500 cases of cardiovascular deaths during the period 2007–2016, and the average concentrations of air pollutants (PM₁₀, SO₂, NO₂, PM₂.₅, CO, O₃) were 106.11, 20.34, 30.49, 72.59, 958.7, and 67.88 μg/m³, respectively. An increase of interquartile range (IQR) in PM₁₀, SO₂, NO₂, PM₂.₅, CO, and O₃ were associated with an increase of 4.34% (95%CI 1.54~7.23%) at lag 0–6, 5.79% (95%CI 2.43~9.27%) at lag 0–5, 4.47% (95%CI 1.64~7.37%) at lag 0–5, 3.14% (95%CI 0.03~6.36%) at lag 0–4, 3.11% (95%CI 0.21~6.10%) at lag 0–3, and 8.17% (95%CI 1.89~14.84%) at lag 0–5 in cardiovascular deaths, respectively. Females, older group (≥ 65 years) and deaths from cerebral vascular disease were more vulnerable to air pollution than males, younger individuals (< 65 years) and deaths from ischemic heart disease. Our results suggest that air pollution increased the risk of cardiovascular deaths in Hefei. These findings can provide evidence for effective air quality interventions in Hefei.
Show more [+] Less [-]Treatment of diesel-contaminated soil using thermal water vapor arc plasma Full text
2020
Gimžauskaitė, Dovilė | Tamošiūnas, Andrius | Tučkutė, Simona | Snapkauskienė, Vilma | Aikas, Mindaugas | Uscila, Rolandas
Soil pollution with petroleum-based fuels is a serious issue causing environmental problems. Recently, the use of plasma technologies for soil remediation has shown an interest and great potential. The remediation process can be performed in a fast timeframe without adding supplementary chemical reagents or without additional pre-treatment of the polluted soil. As a result, the use of plasma enables to obtain highly effective degradation of pollutants. Thus, in the present experimental research, diesel fuel removal from contaminated soil by utilizing thermal water vapor arc plasma was investigated. It was found that increased concentration of diesel fuel in the soil raised carbon and hydrogen concentrations in the soil. Moreover, soil surface morphology was modified by causing the formation of bigger agglomerates. It was also determined that after the plasma treatment process, soil grains became akin in size and structure to clean soil grains. A complete desorption of carbon, which came from diesel fuel to the soil, and a slight decomposition of organic carbon present in the soil were observed during the soil remediation process. Thermogravimetric analysis showed that regardless of the diesel fuel concentration in the soil, four stages of mass loss were observed: moisture loss, vaporization, and combustion of diesel fuel as well as reduction of volatiles and char in the soil. Producer gas analysis indicated that during soil remediation diesel fuel was mainly converted to synthesis gas, i.e., a mixture of H₂, CO, and CO₂. Moreover, the decomposition of diesel fuel and the formation of synthesis gas depended on the amount of pollutant in the soil. According to the obtained results, thermal water vapor arc plasma was able to completely remove diesel fuel from polluted soil in the form of synthesis gas with no significant influence on soil’s properties.
Show more [+] Less [-]Addition of oyster shell to enhance organic matter degradation and nitrogen conservation during anaerobic digestate composting Full text
2020
Lu, Ming-Yi | Shi, Xiao-Shuang | Li, Xu | Lian, Shu-Juan | Xu, Dong-Yan | Guo, Rong-Bo
Anaerobic digested residue (DR) is the main by-product from biogas plants, and it is predominantly used as organic fertilizer after composting. To resolve the problems of long duration and nitrogen loss in conventional composting, bulking agents are always added during the composting process. In this study, oyster shell (OS) was used as a bulking agent for DR composting. Four treatments were conducted by mixing DR and OS at different concentrations (0%, 10%, 20% and 30%, based on wet weight) and then composting the mixtures for 40 days. The results showed that the organic matter (OM) degradation efficiency was enhanced by 5.62%, 12.15% and 16.98% with increasing amounts of OS addition. The increased content of microbial biomass carbon in the compost indicated a suitable living environment for aerobic microbes with added OS, which could explain the increased OM degradation efficiency. Compared with the control, the NH₃ emissions in the treatments with 10%, 20% and 30% OS were decreased by 13.81%, 33.33% and 53.76%, respectively. The increase in total nitrogen content in the compost is probably due to the absorption of NH₃ by OS. Results indicated that OS is a suitable bulking agent for DR composting and that the addition of 20–30% OS can significantly enhance composting performance.
Show more [+] Less [-]Growth and reproduction of Donax trunculus from the Gulf of Annaba (Northeast Algeria) in relation to environmental conditions Full text
2020
Hamdani, Amel | Soltani, Noureddine | Zaidi, Nedjoua
This study was aimed to evaluate the physiological reproductive end points (sex ratio, gametogenic cycle) and biological indices (condition index, length–weight relationship) in D. trunculus collected monthly over the year 2016, from two sites of the Gulf of Annaba (Northeast Algeria): El Battah (relatively unpolluted site) and Sidi Salem (polluted site). The results showed that gametogenesis takes place from December to August in both sites, with an autumnal resting phase. Also, the spawning occurred between March and August with two major spawning phases: April and August in El Battah vs May and August in Sidi Salem. The condition index showed a significant decrease in Sidi Salem site and positive correlation with gonad index. Moreover, the sites exert a significant effect on the allometric relationship and no significant effect on sex ratio. The observed reproductive events are discussed with the changes in the biological indices and the levels of pollution in the studied sites.
Show more [+] Less [-]Dissipation of chlorothalonil in the presence of chlortetracycline and ciprofloxacin and their combined effects on soil enzyme activity Full text
2020
Han, Lingxi | Liu, Yalei | Fang, Kuan | Zhang, Xiaolian | Liu, Tong | Wang, Fenglong | Wang, Xiuguo
The long-term application of substantial amounts of fungicides and antibiotic-polluted organic manure (OM) in greenhouse has caused the co-existence of fungicides and antibiotics in soils. However, little is known about the effects of antibiotics on the persistence of fungicides in soils or their combined effects on soil enzyme activity. In this study, fungicide chlorothalonil (CTL) alone and in combination with antibiotic chlortetracycline (CTC) or ciprofloxacin (CIP) were repeatedly added to OM-amended soil to investigate the changes in the residual characteristics of CTL and in soil dehydrogenase and urease activity. The results showed that CTL rapidly dissipated in soils with the corresponding half-lives of 0.9–3.2, which initially increased, then decreased and finally stabilized with an increased treatment frequency. The dissipation of CTL was inhibited by CTC and CIP during the first several treatments. The soil dehydrogenase and urease activity in CTL-treated soils was inhibited during the first six treatments and then recovered afterwards. Compared with the OM-amended soil+CTL treatment, the OM-amended soil+CTL+CTC and OM-amended soil+CTL+CIP treatments had stronger inhibitory effects on soil enzyme activity during the first six repeated treatments but exhibited slight stimulating effects afterwards. Therefore, the results obtained in this study suggested that the long-term co-existence of CTL, CTC, and CIP altered the dissipation characteristics of CTL in soil and affected the soil enzyme activity levels. The prudent application of large and frequent of fungicides and OM-containing antibiotic residues in greenhouses should therefore be carefully considered in order to reduce the long-term combined pollution in soils.
Show more [+] Less [-]Incorporating social dimensions in hydrological and water quality modeling to evaluate the effectiveness of agricultural beneficial management practices in a Prairie River Basin Full text
2020
Bradford, Lori | Thapa, Anuja | Duffy, Ashleigh | Hassanzadeh, Elmira | Strickert, Graham | Noble, Bram | Lindenschmidt, Karl-Erich
There is growing interest to develop processes for creating user-informed watershed scale models of hydrology and water quality and to assist in decision-making for balanced policies for managing watersheds. Watershed models can be enhanced with the incorporation of social dimensions of watershed management as brought forward by participants such as the perspectives, values, and norms of people that depend on the land, water, and ecosystems for sustenance, economies, and overall wellbeing. In this work, we explore the value of combining both qualitative and quantitative methods and social science data to enhance salience and legitimacy of watershed models so that end-users are more engaged. We discuss pilot testing and engagement workshops for building and testing a systems dynamics model of the Qu’Appelle Valley to gather insights from local farmers and understand their perceptions of Beneficial Management Practices (BMPs). Mixed-method workshops with agricultural producers in the Qu’Appelle Watershed gathered feedback on the developing model and the incorporation of social determinants affecting decision-making. Analysis of focus groups and factor analysis of Q-sorts were used to identify the desired components of the model, and whether it supported farmers’ understanding of the potential effects of BMPs on water quality. We explored farmers’ engagement with models testing BMPs and the potential of incorporating their decision processes within the model itself. Finally, we discuss the reception of the process and the practicality of the approach in providing legitimate and credible decision support tools for a community of farmers.
Show more [+] Less [-]Research trends and hotspots related to global carbon footprint based on bibliometric analysis: 2007–2018 Full text
2020
Yue, Ting | Liu, Haiwen | Long, Ruyin | Chen, Hong | Gan, Xin | Liu, Junli
As an important indicator of greenhouse gas emissions, the carbon footprint (CF) has become increasingly important in recent years under the dual pressures of global warming and international commitments to mitigate its effects. This study collected 3698 papers related to CF from the Web of Science database as research samples (year 2007 to 2018). Based on CiteSpace, the knowledge base, popular topics, and research trends of CF are presented. The results show the following: (1) from 2007 to 2018, the number of articles on CF have steadily increased. (2) After spatial analysis of the literature, we found that among research institutions, the Chinese Academy of Sciences has the largest number of publications on the issue. When it comes to country, three important research forces can be identified: USA, China, and UK. (3) Research on the CF is interdisciplinary; in addition to the traditional fields of environmental, political, economics, and computing, CF research has received attention from the Physics, Materials, Chemistry, Mathematics, and animal sciences. (4) Through keyword clustering, currently popular topics in research can be roughly divided into four aspects: CF calculation methods, research scales, energy, and agriculture. (5) The CF research during the study period is divided into four stages according to the burst time and content of the burst keywords. According to the research status and trend, this paper puts forward the future research direction of carbon footprint.
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