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Correction to: Migration and transformation of different phosphorus forms in rainfall runoff in bioretention system
2019
Song, Yujia | Song, Shoufa
The corresponding Author of this paper transferred to another institution. The correct affiliation is shown in this paper.
Show more [+] Less [-]Understanding the effect of indoor air pollution on pneumonia in children under 5 in low- and middle-income countries: a systematic review of evidence
2019
Adaji, Enemona Emmanuel | Ekezie, Winifred | Clifford, Michael | Phalkey, Revati
Exposure to indoor air pollution increases the risk of pneumonia in children, accounting for about a million deaths globally. This study investigates the individual effect of solid fuel, carbon monoxide (CO), black carbon (BC) and particulate matter (PM)₂.₅ on pneumonia in children under 5 in low- and middle-income countries. A systematic review was conducted to identify peer-reviewed and grey full-text documents without restrictions to study design, language or year of publication using nine databases (Embase, PubMed, EBSCO/CINAHL, Scopus, Web of Knowledge, WHO Library Database (WHOLIS), Integrated Regional Information Networks (IRIN), the World Meteorological Organization (WMO)-WHO and Intergovernmental Panel on Climate Change (IPCC). Exposure to solid fuel use showed a significant association to childhood pneumonia. Exposure to CO showed no association to childhood pneumonia. PM₂.₅ did not show any association when physically measured, whilst eight studies that used solid fuel as a proxy for PM₂.₅ all reported significant associations. This review highlights the need to standardise measurement of exposure and outcome variables when investigating the effect of air pollution on pneumonia in children under 5. Future studies should account for BC, PM₁ and the interaction between indoor and outdoor pollution and its cumulative impact on childhood pneumonia.
Show more [+] Less [-]Testing the impact of real interest rate, income, and energy consumption on Turkey’s CO2 emissions
2019
Isiksal, Aliya Zhakanova | Samour, Ahmed | Resatoglu, Nil Gunsel
This paper aims to explore the impact of real interest rates (RIN), income, trade, foreign direct investment (FDI), and energy consumption on Turkey’s carbon dioxide emissions (CO₂) over the period from 1980 to 2014. This study differs from the existing literature by introducing a new discussion in the determination of environmental degradation, namely real interest rate. Hatemi-J (HJ) cointegration with two structural breaks and the newly developed Bayer–Hanck (BH) combined cointegration tests are used to enhance and support the robustness of the autoregressive distributed lag (ARDL) bounds test. The Granger causality test within the vector error correction model (VECM) is employed to examine the causality direction among the variables in both the short and long run. The empirical results demonstrate that RIN negatively effects CO₂ emissions. This impact is also supported through energy, income, and FDI channels. It is suggested that policy makers should promote the stability of the real interest rates channel to reduce CO₂ emissions and encourage the renewable energy investment through the production of electricity using renewable sources.
Show more [+] Less [-]Soil-indigenous arbuscular mycorrhizal fungi and zeolite addition to soil synergistically increase grain yield and reduce cadmium uptake of bread wheat (through improved nitrogen and phosphorus nutrition and immobilization of Cd in roots)
2019
Baghaie, Amir Hossein | Aghili, Forough | Jafarinia, Reza
Soil pollution with heavy metals is a major problem in industrial areas. Here, we explored whether zeolite addition to soil and indigenous arbuscular mycorrhizal fungi (AMF) can reduce cadmium (Cd) uptake from soil by bread wheat. We conducted a pot experiment, in which the effects of indigenous soil AMF, zeolite addition, and Cd spiking to soil [0, 5, 10, and 15 mg (kg soil)⁻¹] were tested. Zeolite addition to soil spiked with 15 mg Cd kg⁻¹ decreased the Cd uptake to grains from 11.8 to 8.3 mg kg⁻¹ and 8.9 to 3.3 mg kg⁻¹ in the absence and presence of indigenous AMF, respectively. Positive growth, nitrogen (N), and phosphorous (P) uptake responses to mycorrhization in Cd-spiked soils were consistently magnified by zeolite addition. Zeolite addition to soil stimulated AMF root colonization. The abundance of AMF taxa changed in response to zeolite addition to soil and soil Cd spiking as measured by quantitative polymerase chain reaction. With increasing Cd spiking, the abundance of Funneliformis increased. However, when less Cd was spiked to soil and/or when zeolite was added, the abundance of Claroideoglomus and Rhizophagus increased. This study showed that soil-indigenous AMF and addition of zeolite to soil can lower Cd uptake to the grains of bread wheat and thereby reduce Cd contamination of the globally most important staple food.
Show more [+] Less [-]Evaluation of phytotoxicity of three organic amendments to collard greens using the seed germination bioassay
2019
Kebrom, Tesfamichael H. | Woldesenbet, Selamawit | Bayabil, Haimanote K. | Garcia, Monique | Gao, Ming | Ampim, Peter | Awal, Ripendra | Fares, Ali
Small-scale vegetable and fruit crop producers in the USA use locally available commercial organic fertilizers and soil amendments recycled from municipal and agricultural wastes. Organic soil amendments provide crops with their nutrient needs and maintain soil health by modifying its physical, chemical, and biological properties. However, organic soil amendments might add unwanted elements such as toxic heavy metals or salts, which might inhibit crop growth and reduce yield. Therefore, the objective of this study was to evaluate phytotoxicity of three commercial organic amendments, chicken manure, milorganite, and dairy manure, to collard greens using the seed germination bioassay and chemical analysis of the organic amendments. The seed germination bioassay was conducted by incubating collard greens seeds to germinate in 1:10 (w/v) organic amendment aqueous extracts. Results of this work identified phytotoxic effects of chicken manure and milorganite, but not dairy manure, to collard greens. Potentially phytotoxic chemicals such as copper, zinc, nickel, and salts were also higher in chicken manure and milorganite compared to dairy manure. In particular, nickel in chicken manure and milorganite aqueous extracts was 28-fold and 21-fold, respectively, higher than previously reported toxic levels to wheat seedlings. The results demonstrate the need for more research on phytotoxicity of commercial organic soil amendments to ensure their safe use in vegetable and fruit crop production systems.
Show more [+] Less [-]Environmental risk appraisement of disinfection by-products (DBPs) in plant model system: Allium cepa
2019
Ranjan, Jyoti | Mandal, Tamal | Mandal, Dalia Dasgupta
The organic toxicants formed in chlorinated water cause potential harm to human beings, and it is extensively concentrated all over the world. Various disinfection by-products (DBPs) occur in chlorinated water are genotoxic and carcinogenic. The toxicity is major concern for chlorinated DBPs which has been present more in potable water. The purpose of the work was to evaluate genotoxic properties of DBPs in Allium cepa as a plant model system. The chromosomal aberration and DNA laddering assays were performed to examine the genotoxic effect of trichloroacetic acid (TCAA), trichloromethane (TCM), and tribromomethane (TBM) in a plant system with distinct concentrations, using ethyl methanesulfonate (EMS) as positive control and tap water as negative control. In Allium cepa root growth inhibition test, the inhibition was concentration dependent, and EC₅₀ values for trichloroacetic acid (TCAA), trichloromethane (TCM), and tribromomethane (TBM) were 100 mg/L, 160 mg/L, and 120 mg/L respectively. In the chromosome aberration assay, root tip cells were investigated after 120 h exposure. The bridge formation, sticky chromosomes, vagrant chromosomes, fragmented chromosome, c-anaphase, and multipolarity chromosomal aberrations were seen in anaphase–telophase cells. It was noticed that with enhanced concentrations of DBPs, the total chromosomal aberrations were more frequent. The DNA damage was analyzed in roots of Allium cepa exposed with DBPs (TCAA, TCM, TBM) by DNA laddering. The biochemical assays such as lipid peroxidation, H₂O₂ content, ascorbate peroxidase, guaiacol peroxidase, and catalase were concentration dependent. The DNA interaction studies were performed to examine binding mode of TCAA, TCM, and TBM with DNAs. The DNA interaction was evaluated by spectrophotometric and spectrofluorometric studies which revealed that TCAA, TCM, and TBM might interact with Calf thymus DNA (CT- DNA) by non-traditional intercalation manner.
Show more [+] Less [-]The possible neuroprotective effects of melatonin in aluminum chloride-induced neurotoxicity via antioxidant pathway and Nrf2 signaling apart from metal chelation
2019
Sadek, Kadry M. | Lebda, Mohamed A. | Abouzed, Tarek K.
Aluminum (Al) had well-identified adverse influences on the nervous system mainly through the creation of reactive oxygen species (ROS). Melatonin works as an antioxidant through the inhibition of ROS and attenuating peroxidation of lipids. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a pivotal transcription factor which controls the transcription of antioxidant enzymes. This study was conducted to determine the potential neuroprophylactic impacts of melatonin in aluminum chloride (AlCl₃)-initiated neurotoxicity including potential mechanism(s) of action and relevant signaling in rats. Thirty-six male rats were distributed into 4 groups: Control; AlCl₃ (50 mg/kg bwt, i.p, 3 times weekly for 3 months); melatonin (5 mg/kg bwt, i.p daily for 2 weeks before AlCl₃ and sustained for the next 3 months); and melatonin with AlCl₃. Neuronal alterations were histopathologically and biochemically evaluated. The neuronal antioxidant-related genes and relevant Nrf2 protein expression were determined by real-time PCR and Western blotting, respectively. The current data showed a substantial increase in brain damage biomarkers, acetylecholinesterase (AchE) activity, and malondialdehyde (MDA) content while the enzymatic antioxidant expression as glutathione-s-transferase (GST), catalase (CAT), and superoxide dismutase (SOD) were substantially attenuated in the aluminum-treated group, with cleared histopathological changes as inflammatory cell infiltration with neuronal degeneration. Supplementation of melatonin resulted in an obvious amelioration in all previous abnormal alteration observed in AlCl₃-treated rats rather than increased Al burden and/or altered Fe and Cu homeostasis with upregulating both total and phosphorylated Nrf2 expression. Therefore, the study concluded that melatonin has a potential ability to be neuroprophylactic against Al-induced neurotoxic effect and oxidative damage in the rat brain through upregulating and instigating Nrf2 signaling apart from metal chelation.
Show more [+] Less [-]Correction to: Cellular distribution of cadmium in two amaranth (Amaranthus mangostanus L.) cultivars differing in cadmium accumulation
2019
Chi, Keyu | Zou, Rong | Wang, Li | Huo, Wenmin | Fan, Hongli
The article Cellular distribution of cadmium in two amaranth (Amaranthus mangostanus L.) cultivars differing in cadmium accumulation, written by Keyu Chi, Rong Zou, Li Wang, Wenmin Huo and Hongli Fan, was originally published electronically on the publisher’s internet portal (currently SpringerLink)
Show more [+] Less [-]Seasonal changes in the chemical composition and reactivity of dissolved organic matter at the land-ocean interface of a subtropical river
2019
Yang, Liyang | Cheng, Qiong | Zhuang, Wan-E | Wang, Hui | Chen, Wei
Dissolved organic matter (DOM) is a critical component in aquatic ecosystems, yet its seasonal variability and reactivity remain not well constrained. These were investigated at the land-ocean interface of a subtropical river (Minjiang River, SE China), using absorption and fluorescence spectroscopy. The annual export flux of dissolved organic carbon (DOC) from the Minjiang River (5.48 × 10¹⁰ g year⁻¹) was highest among the rivers adjacent to the Taiwan Strait, with 72% occurring in spring and summer. The freshwater absorption coefficient a₂₈₀, DOC-specific UV absorbance SUVA₂₅₄ and humification index HIX were higher, while the spectral slope S₂₇₅–₂₉₅ and biological index BIX were lower in summer than in winter. This suggests intensified export of terrestrial aromatic and high molecular weight constituents in the rainy summer season. Six fluorescent components were identified from 428 samples, including humic-like C1–C3, tryptophan-like C4 and C6, and tyrosine-like C5. The freshwater levels of four components (C1, C2, C4, and C6) were lower while that of C5 was higher in the wet season than in the dry season, suggesting contrasting seasonal variations of different constituents. Laboratory experiments were performed to assess the effects of photochemical and microbial degradation on DOM. Photo-degradation removed chromophoric and fluorescent DOM (CDOM and FDOM) effectively, which was stronger (i) for high molecular weight/humic constituents and (ii) during summer under higher solar radiation. Microbial degradation under laboratory controlled conditions generally showed little effect on DOC, and had smaller impact on CDOM and FDOM in winter than in summer. Overall, this study showed notable seasonal changes in the chemical composition and reactivity of DOM at the land-ocean interface, and demonstrated the significant effects of photo-degradation.
Show more [+] Less [-]Characterization and source estimates of primary and secondary carbonaceous aerosols at urban and suburban atmospheres of Düzce, Turkey
2019
Aslan Kılavuz, Seda | Bozkurt, Zehra | Öztürk, Fatma
Düzce is one of the cities located in the western Black Sea region of Turkey with a population of 377,610 in 2017 (TUIK, 2017). There is no satisfying scientific information available to address the contribution of primary and secondary sources of carbonaceous aerosols to the observed PM₁₀ levels in the city. The main objective of the study is to determine the levels and sources of carbonaceous aerosols in PM₁₀. For this purpose, PM₁₀ samples were collected at urban and suburban locations in Düzce during winter and summer season in 2015. Average summer OC and EC concentrations in the urban area were 9.5 and 1.3 μg m⁻³, respectively, while the corresponding concentrations were observed as 28.5 and 2.3 μg m⁻³, respectively for winter season. Summer mean OC and EC levels at the suburban site were 5.46 and 0.37 μg m⁻³, respectively, while those for winter were found as 6.68 and 0.61 μg m⁻³.The contributions of OC and EC to measured PM₁₀ levels were found in the range of 10% to 60% and 1% to 7%, respectively, at the urban station while the associated contributions were in the range of 10% to 50% and 0.6% to 6%, respectively, at the suburban station. The concentrations measured during winter months in both areas were found to be higher than those measured during summer months. The EC tracer method was used in order to estimate the SOC contribution. The contribution of SOC concentrations to the total PM₁₀ mass was found to be higher during winter in the urban area and during summer in the suburban area.
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