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Enhanced arsenate removal from aqueous solution by Mn-doped MgAl-layered double hydroxides
2019
Li, Shifeng | Guo, Yang | Xiao, Min | Zhang, Tan | Yao, Shuhua | Zang, Shuyan | Fan, Hongtao | Shen, Yanming | Zhang, Zhigang | Li, Wenxiu
In this study, Mn-doped MgAl-layered double hydroxides (LDHs) were successfully synthesized for efficient removal arsenate from aqueous solution. The structure and composition of Mn-doped MgAl-LDHs intercalated by different ions such as CO₃²⁻, Cl⁻, or NO₃⁻ were investigated. The characterizations of XRD, ATR FT-IR, SEM, TG-DTA, and N₂ adsorption-desorption presented that the Mn-doped MgAl-LDHs (donated as Mn-LDHs) have very similar physical morphologies and properties to the MgAl-Cl-LDHs (donated as Mg-LDHs). However, the Mn-LDHs exhibits more preferable arsenate adsorption than Mg-LDHs. The As(V) removal kinetics data of Mn-LDHs is followed pseudo-second-order expression. The adsorption capacity of As(V) on Mn-LDHs via Langmuir isotherm model was 166.94 mg g⁻¹. The results of XPS revealed that the enhanced removal mechanism can be attributed to surface complexation of As(V) with Mn on the surface of Mn-LDHs. These results prove that Mn-doped LDHs can be considered as a potential material for adsorption As(V) from wastewater.
Show more [+] Less [-]Using multi-integrated biomarker indexes approach to assess marine quality and health status of marine organism: a case study of Ruditapes philippinarum in Laizhou Bay, China
2019
Ji, Rongwang | Pan, Luqing | Guo, Ruiming | Zheng, Lei | Zhang, Mengyu
With the progress of technology and the deepening of understanding of biological monitoring, much more attention has been paid to the multiple evaluation of marine pollution monitoring. In view of this, our study aimed at establishing a multi-integrated biomarker indexes approach to evaluate marine condition systematically and comprehensively. In the current study, sampling was conducted in Laizhou Bay, China (S1, S2, and S3) in May, August, and October of 2015. And then, multi-integrated biomarker indexes approach was applied to assess marine PAHs pollution, select appropriate biomarkers, and evaluate marine environmental quality and health status of the clams of Ruditapes philippinarum. As the results showed, S2 was the most PAHs-polluted site while S1 was the least polluted site, and the levels of tPAHs in seawater and sediments ranged from 69.78 to 315.30 ng/L and 163.19 to 565.17 ng/g d.w., respectively. And all three sampling sites had different sources of PAHs. IBR represented DNA damage (F value), the expression of SOD, EROD activity, GST activity, and LPO could be served as biomarkers to monitor the PAHs pollution in Laizhou Bay. And MPI suggested the quality of all three sites: S1 was generally favorable, S2 was moderately polluted, and S3 was lightly polluted. BRI values showed that the order of health status of R. philippinarum was S1 > S3 > S2.
Show more [+] Less [-]Phytoextraction of heavy metals from contaminated soil, water and atmosphere using ornamental plants: mechanisms and efficiency improvement strategies
2019
Asgari Lajayer, Behnam | Khadem Moghadam, Nader | Maghsoodi, Mohammad Reza | Ghorbanpour, Mansour | Kariman, Khalil
Accumulation of heavy metals (HMs) in soil, water and air is one of the major environmental concerns worldwide, which mainly occurs due to anthropogenic activities such as industrialization, urbanization, and mining. Conventional remediation strategies involving physical or chemical techniques are not cost-effective and/or eco-friendly, reinforcing the necessity for development of novel approaches. Phytoextraction has attracted considerable attention over the past decades and generally refers to use of plants for cleaning up environmental pollutants such as HMs. Compared to other plant types such as edible crops and medicinal plants, ornamental plants (OPs) seem to be a more viable option as they offer several advantages including cleaning up the HMs pollution, beautification of the environment, by-product generation and related economic benefits, and not generally being involved in the food/feed chain or other direct human applications. Phytoextraction ability of OPs involve diverse detoxification pathways such as enzymatic and non-enzymatic (secondary metabolites) antioxidative responses, distribution and deposition of HMs in the cell walls, vacuoles and metabolically inactive tissues, and chelation of HMs by a ligand such as phytochelatins followed by the sequestration of the metal–ligand complex into the vacuoles. The phytoextraction efficiency of OPs can be improved through chemical, microbial, soil amending, and genetic approaches, which primarily target bioavailability, uptake, and sequestration of HMs. In this review, we explore the phytoextraction potential of OPs for remediation of HMs-polluted environments, underpinning mechanisms, efficiency improvement strategies, and highlight the potential future research directions.
Show more [+] Less [-]Assessment of Melissa officinalis L. essential oil as an eco-friendly approach against biodeterioration of wheat flour caused by Tribolium castaneum Herbst
2019
Upadhyay, Neha | Singh, Vipin Kumar | Dwivedy, Abhishek Kumar | Das, Somenath | Chaudhari, Anand Kumar | Dubey, N. K.
The study reports efficacy of Melissa officinalis L. essential oil (MOEO) as a safe plant-based insecticide against Tribolium castaneum Herbst (TC) by induction of oxidative stress. MOEO nanoencapsulation in chitosan matrix was performed to enhance its bioefficacy. GC–MS analysis of MOEO depicted geranial (31.54%), neral (31.08%), and β-caryophyllene (12.42%) as the major components. MOEO showed excellent insecticidal potential in contact (100% mortality at 0.157 μL/cm²) and fumigant bioassays (LC₅₀ = 0.071 μL/mL air) and 100% repellency at concentration ≤ 0.028 μL/cm². Increased reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), and decreased ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) at the LC₅₀ dose suggested significant oxidative stress on TC in MOEO treatment sets. The encapsulated MOEO exhibited enhanced activity as fumigant (LC₅₀ = 0.048 μL/mL air) and showed significant antifeedant activity in situ (EC₅₀ = 0.043 μL/mL). High LD₅₀ value (13,956.87 μL/kg body weight of mice) confirmed favorable toxicological profile for non-target mammals. The findings depict potential of nanoencapsulated MOEO as an eco-friendly green pesticide against infestation of stored food by TC.
Show more [+] Less [-]Presence of bacteroidales as a predicator of human enteric viruses in Haihe River of Tianjin City, China
2019
Zhou, Shuqing | Yang, Dong | Xu, Qunying | Yang, Zhongwei | Jin, Min | Yin, Jing | Wang, Huaran | Zhou, Kun | Wang, Lianqi | Li, Junwen | Shen, Zhiqiang
Traditional microbe indicators including total bacteria, total coliforms, fecal coliforms, Escherichia coli, enterococci, and F+ coliphage are all frequently used to characterize the microbial contamination state of water bodies for their correlation with pathogenic bacteria. However, these indicators have a poor relationship with viruses, which pose serious threat to economic and human health. Alternative indicators such as bacteroidales may be suitable complementary alternatives to traditional microbe indicators and are being increasingly reported. In the present study, water was analyzed for selected sites along Haihe River in Tianjin for traditional indicators, an alternative indicator (bacteroidales), pathogenic bacteria (Salmonella, Escherichia coli (E. coli) O157:H7, and Vibrio parahaemolyticus), viruses (enteric adenovirus, norovirus, enterovirus, poliovirus and rotavirus), and physicochemical parameters. Results indicated that traditional microbe indicators detected in this study showed good correlation with pathogenic bacteria, and the alternative indicator (bacteroidales) had a surprisingly good relationship with viral presence. We propose that bacteroidales might be a suitable complementary indicator for viral contamination in water bodies.
Show more [+] Less [-]Elemental imbalance elicited by arsenic and copper exposures leads to oxidative stress and immunotoxicity in chicken gizzard, activating the protective effects of heat shock proteins
2019
Guo, Menghao | Zhao, Hongjing | Wang, Yu | Liu, Juanjuan | Fei, Dongxue | Yang, Xin | Mu, Mengyao | Xing, Mingwei
Arsenic (As) and copper (Cu) are ubiquitous pollutants that pose a threat to the environment. Our aim is to study the underlying mechanisms by which As and Cu act on the chicken gizzard. In order to detect ionic disorders in chicken gizzard under chronic treatment with As³⁺ and/or Cu²⁺ and whether they can induce oxidative damage as well as immune disorders, 30 mg/kg arsenic trioxide (As₂O₃) and/or 300 mg/kg copper sulfate (CuSO₄) were added to the chicken’s basal diet. After 12 weeks of exposure, trace elements were found to have significant interference, accompanied by damage to the antioxidant system. In addition, As³⁺ and/or Cu²⁺ activated the nuclear factor kappa B (NF-κB), inducing severe inflammation. At the same time, damaged structural integrity which might be caused by inflammation was discovered after hematoxylin and eosin (H&E) staining. Moreover, symbolic Th1/Th2 (Th, helper T cell) drift was also observed in treatment groups, meaning that immune function is left to be affected, and the increment in heat shock proteins may be a self-protective mechanism of gizzard. Interestingly, we found that the damage to the gizzard of chicken was aggravated in a time-dependent manner, and the combined exposure was more pathogenic than the single exposure, of which the mechanism needs further exploration. Together, this work helps move us toward a better understanding of the molecular mechanisms that mediate the interactions between Cu excess and As³⁺ exposures and possible health consequences in susceptible species.
Show more [+] Less [-]Economic growth, natural resources, and ecological footprints: evidence from Pakistan
2019
Hassan, Syed Tauseef | Xia, Enjun | Khan, Noor Hashim | Shah, Sayed Mohsin Ali
The ecological footprint, a measure of human demand on earth’s ecosystems, represents the amount of biologically productive land and sea area that is necessary to supply the resources a human population consumes and to mitigate associated waste. This study estimates the impact of economic growth and natural resources on Pakistan’s ecological footprint using an autoregressive distributive lag (ARDL) model for long-run estimation. The empirical findings indicate that natural resources have a positive effect on an ecological footprint that deteriorates environmental quality and that natural resources help to support the environmental Kuznets hypothesis (EKC). Bidirectional causality is found between natural resources and the ecological footprint, along with a long-run causality between biocapacity and the ecological footprint. The innovative findings have important implications for policy.
Show more [+] Less [-]Camera sensor-based contamination detection for water environment monitoring
2019
Wang, Yong | Zhang, Xufan | Chen, Jun | Cheng, Zhuo | Wang, Dianhong
Water environment monitoring is of great importance to human health, ecosystem sustainability, and water transport. Unlike traditional water quality monitoring problems, this paper focuses on visual perception of water environment. We first introduce the development of a customized aquatic sensor node equipped with an embedded camera sensor. Based on this platform, we present an efficient and holistic contamination detection approach, which can automatically adapt to the detection of floating debris in dynamic waters or the identification of salient regions in static waters. Our approach is specifically designed based on compressed sensing theory to give full consideration to the unique challenges in water environment and the resource constraints on sensor nodes. Both laboratory and field experiments demonstrate the proposed method can fast and accurately detect various types of water pollutants and is a better choice for camera sensor-based water environment monitoring compared with other methods.
Show more [+] Less [-]Inter-species and inter-colony differences in elemental concentrations in eggshells of sympatrically nesting great cormorants Phalacrocorax carbo and grey herons Ardea cinerea
2019
Jakubas, Dariusz | Kitowski, Ignacy | Wiącek, Dariusz | Bzoma, Szymon
We compared the concentrations of 17 heavy metals and essential elements in post-hatching eggshells of two waterbirds, the obligate piscivorous great cormorant Phalacrocorax carbo (GCM) and the more omnivorous grey heron Ardea cinerea (GHR), breeding sympatrically in eight mixed colonies in Poland. We found significant inter-species and inter-colony differences in the levels of most of the elements. GHR had significantly higher concentrations of Al, which can be explained by its very low stomach pH: an acidic environment favours the release of Al compounds. Differences in Mn, Ni, Cu, Se and Hg concentrations can be attributed to the various contributions of fish and other aquatic organisms to the diet, and to the exploration of different habitats (GCM exclusively aquatic, GHR a wider range) and microhabitats (GCM, in contrast to wading GHR, dive for food, exploring the whole depth range of water bodies), differently exposed to contamination by those elements from sediments. Inter-colony differences were related to the level of industrialisation. We recorded higher levels of some elements in the eggshells (Fe, Mn in both species and Cr, Ni and Zn in GCM) collected in industrialised areas, which may be associated with the negative environmental impact of industrial areas.
Show more [+] Less [-]A study of the predictive factors of mortality in acute poisoning with aluminum phosphide with special reference to echocardiography and SOFA score
2019
Sheta, Abeer A. | El-Banna, Asmaa S. | Elmeguid, Rania Abd | Mohamed, Hany E. | Gad, Nehad H.
Aluminum phosphide (AlP) is considered now one of the most common causes of poisoning among agricultural pesticides. Poisoning with AlP is extremely toxic to humans with high mortality rate. The aim of this work was to evaluate the prognostic factors and outcome of acute aluminum phosphide poisoning in Alexandria Main University Hospital during a period of 6 months from 1 November 2017 until the end of April 2018, highlighting the role of SOFA score and echocardiography in predicting the mortality. The prospective study was conducted on all patients admitted with acute AlP poisoning to Alexandria Main University Hospital for those 6 months. Patients’ data were collected in a special sheet and included biosocial data, medical history, poisoning history, complete medical examination, investigations, duration of hospital stay, and the outcome. All patients were assessed according to SOFA score on admission. Thirty patients were admitted during the period of the current study. Females outnumbered males in all age groups with a sex ratio of 2.75:1. The mean age of patients was 22.77 ± 12.79 years. 96.6% of patients came from rural areas. 93.3% of the cases were exposed to poisoning at home, where suicidal poisoning accounted for (86.7%) of cases. 43.3% of patients died (n = 13), and the median value of SOFA score among non-survivors was 10, versus 1 among survivors. The median value of ejection fraction among non-survivors (25%) was half its value in survivors (50%). Although there were many predictors of severity of AlP poisoning, SOFA score was the most predictive factor of mortality detected by multivariate analysis.
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