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Date palm fruit extract ameliorated pancreatic apoptosis, endocrine dysfunction and regulatory inflammatory cytokines in Streptozotocin-induced diabetes in rats Texte intégral
2020
Hafez, Mona H. | Elblehi, Samar S. | El-Sayed, Yasser S.
The current work studied the mechanism(s) and ability by which date palm (Phoenix dactylifera L.) fruit extract (DPE) inspired a glucose-lowering impact in rats suffering from diabetes. Forty-eight albino rats were divided into six various experimental treatments after induction of diabetes by intraperitoneal infusion of streptozotocin (45 mg/kg bwt) as follows: normal control, DPE, diabetic control, diabetic glibenclamide (GLI), diabetic DPE, and diabetic GLI plus DPE-treated groups. In animals euthanized after 8 weeks, blood and pancreatic tissue samples were assembled to assess different biochemical and histopathological changes. The expressions of insulin, B cell lymphoma-2 (Bcl-2), and cysteine aspartate-specific protease-3 (caspase-3) in islet β cells were also evaluated using immunohistochemical assessment. Diabetic rats exhibited hyperglycemia; increment of pancreatic malondialdehyde (lipid peroxidation biomarker), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β); and decrement of plasma insulin and pancreatic antioxidants: glutathione, superoxide dismutase, and catalase values. Also, the pancreatic islets exhibited histopathological and morphometric alternations associated with weak positive insulin and Bcl-2 immunoreactivity and strong positive caspase-3 immunoreactivity. DPE and/or GLI, an anti-diabetic drug, improved the pancreatic histoarchitecture and improved β cell function and structure, which increased insulin levels and improved the insulin, Bcl-2, and caspase-3 immunoreactivity in diabetic rats. Nevertheless, the combined DPE and GLI therapy revealed a significant recovery and restoration of β cells’ structure and function. The date palm fruit has anti-apoptotic, anti-inflammatory, and antioxidant activities and hypoglycemic effects, which in turn play a pivotal role in avoiding the progression of diabetes mellitus. Moreover, it could potentiate the glucose-lowering activity of anti-diabetic drugs.
Afficher plus [+] Moins [-]Examining the impact of polycentric urban form on air pollution: evidence from China Texte intégral
2020
Meichang, Wang | Bingbing, Zhang
Numerous studies on megacities have reported less air pollution in polycentric form urban than monocentric form urban. However, findings from these studies do not imply that increasing air pollution in region or country is accompanied by the expanding megacities. Using satellite night-light data, this study investigates the impact of polycentric urban form at the provincial level on PM₂.₅ concentrations in China while controlling for variables of urban population size, energy consumption, and the weather. The results reveal that the PM₂.₅ concentrations are reduced by 1.46% to 2.67%, with a 1% increase in polycentric urban form. The similar impact has also been observed in the South China, but larger in the Central China. Further studies show that the urban form-air pollution relationship mainly influenced by transportation distance and enhanced by rising per capita income. The findings suggest that regional planning and policies favoring polycentric urban patterns should be strengthened to alleviate air pollution.
Afficher plus [+] Moins [-]Modification of epoxy groups of poly(hydroxylmethyl methacrylate-co-glycidyl methacrylate) cryogel with H3PO4 as adsorbent for removal of hazardous pollutants Texte intégral
2020
Bayramoglu, Gulay | Arica, Mehmet Yakup
Poly(hydroxylmethyl methacrylate-co-glycidyl methacrylate) (p(HEMA-GMA)) macroporous cryogel with high density of epoxy groups was synthesized, and the epoxy groups of the cryogel were modified into phosphonate groups. The effects of dye concentrations, adsorption time, pH, salt concentration, and adsorption temperature on the adsorption of Direct Blue-53 (DB-53) and Reactive Blue-160 (RB-160) dyes were studied. The maximum adsorption capacity was found to be 245.3 and 155.8 mg/g (0.255 or 0.119 mmol/g) for the DB-53 and RB-160 dyes, respectively. The higher adsorption capacity achieved for the DB-53 compared with the RB-160 dye can result from the pendant primary amino groups of the DB-53 dye as well as the smaller size of the dye molecule. The Langmuir isotherm model and the pseudo-second-order kinetic model well described the experimental data. The p(HEMA-GMA)-PO₄²⁻ adsorbent has many operational advantages for the removal of pollutants. It could be a promising adsorbent to be used in industrial wastewater treatment.
Afficher plus [+] Moins [-]Global characteristics and trends of research on construction dust: based on bibliometric and visualized analysis Texte intégral
2020
Guo, Ping | Tian, Wei | Li, Huimin | Zhang, Guangmin | Li, Jianhui
The booming construction industry has led to many environmental and occupational health and safety problems. Construction dust caused irreversible damage to the health of frontline workers and polluted the surrounding air environment, which has attracted the attention of researchers and practitioners. In this study, to systematically sort and analyze the distribution of construction dust (CD) research, its hot areas, and the evolution of its fronts, papers with “construction dust” as the subject term in the Web of Science Core Collection Database since 2010 are visually analyzed using CiteSpace. The characteristics of these papers, including the quantity trend, quality, author group, affiliated institution type, and journal type, are summarized, and keyword co-appearance and paper co-citation knowledge maps are produced. The results show that (1) China is the backbone of CD research, and the research results account for a considerable proportion of the total. (2) Respiratory dust and atmospheric aerosols, marble dust, PM₂.₅, and other hot issues have always attracted international attention. And exposure assessment and spatial distribution were the main focuses in the study of CD. (3) The direction of CD research will explore in a more subtle and intelligent direction in the future, for example, monitoring and control equipment under the technical support of big data technology and machine learning and face recognition. By combining bibliometrics with a systematic review, we aim to analyze the research foci and future development direction deeply, providing scholars with a comprehensive view of the field.
Afficher plus [+] Moins [-]Dunite carbonation in batch-tubular reactor Texte intégral
2020
Agrawal, Amit Kumar | Mehra, Anurag
For geological carbon sequestration, the reaction of aqueous CO₂ with silicate rock permits carbonate formation, achieving permanent carbon sequestration. The fractures available in silicate rock provide significant surface area for the precipitation of carbonates. The experiments were performed in a batch tubular reactor under diffusion-limited condition, with a special arrangement of a narrow tube filled with a 2800 g/L dunite slurry. The tube was kept open from the top, standing vertically filled with a CO₂-rich bulk solution under 1 barg CO₂ and temperatures ranging from 25 to 75 ᵒC for 7–30 days. After 7 days of the experiment, magnesite precipitation was seen inside the tube and the precipitation was continued for up to 30 days. The magnesite precipitation was identified by micro-Raman spectroscopy, X-ray diffraction, and scanning electron microscopy. Additionally, SiO₂ formation was seen in relative close vicinity to the magnesite precipitation. The precipitation on the surface of silicate rock might cover the fractures and pore spaces available, which may over time reduce the dissolution rate of dunite. Graphical Abstract
Afficher plus [+] Moins [-]Transcriptome analysis revealed cadmium accumulation mechanisms in hyperaccumulator Siegesbeckia orientalis L Texte intégral
2020
Xu, Xiaoxun | Zhang, Shirong | Cheng, Zhang | Li, Ting | Jia, Yongxia | Wang, Guiyin | Yang, Zhanbiao | Xian, Junren | Yang, Yuanxiang | Zhou, Wei
Siegesbeckia orientalis L. was identified as a novel Cd-hyperaccumulator and valuable phytoremediation material. However, the molecular mechanisms underlying Cd accumulation in S. orientalis are largely unknown. In this study, RNA-Seq analysis was performed to study the Cd-accumulating mechanisms in its roots with or without Cd treatment. The RNA-seq analysis generated 312 million pairs of clean reads and 78G sequencing data. De novo transcriptome assembly produced 355,070 transcripts with an average length of 823.59 bp and 194,207 unigenes with an average length of 605.68 bp. Comparative transcriptome analyses identified a large number of differentially expressed genes in roots under Cd stress, and functional annotation suggested that S. orientalis utilizes various biological pathways involving many gene networks working simultaneously to cope with the stress. This study revealed that four biological pathways were mainly involved in S. orientalis tolerance to Cd stress, including reactive oxygen species scavenging, phenylpropanoid biosynthesis pathway, Cd absorption and transport, and ABA signaling pathway. The genes related to photosynthesis and heavy metal transport are likely the potential candidates and could be further investigated to determine their roles in Cd tolerance in S. orientalis roots. These findings will be useful to understand the Cd accumulation mechanisms in S. orientalis and facilitate the study of phytoremediation at the molecular level in plants.
Afficher plus [+] Moins [-]Occurrence and removal of 10 odorous compounds in drinking water by different treatment processes Texte intégral
2020
Feng, Guixue | Jia, Ruibao | Sun, Shaohua | Wang, Mingquan | Zhao, Qinghua | Xin, Xiaodong | Liu, Li
This study investigated the prevalence of ten odorous compounds (2-methylisoborneol, trans-1,10-dimethyl-trans-9-decalol, isophorone, 2,4,6-trichloroanisole, 2,3,6-trichloroanisole, 2,3,4-trichloroanisole, β-cyclocitral, β-ionone, 2-isobutyl-3-methyoxypyrazine, and 2-isopropyl-3-methoxypyrazine) in raw drinking water, as well as their removal by traditional processes, advanced oxidation processes, ultrafiltration, and nanofiltration processes, with the use of an ultrahigh-resolution Orbitrap. The most abundant odorous compounds referred to 2-methylisoborneol and trans-1,10-dimethyl-trans-9-decalol with maximal concentrations of 1.6 ng/L and 0.09 ng/L after treatment by traditional processes respectively, and their maximal concentration was 2.05 ng/L and lower than the detection limit after treatment by advanced oxidation processes, while the raw drinking water of the mentioned two processes was different. The high concentration of isophorone in water treated by traditional process, advanced oxidation process, and membrane process was also ascertained. On the whole, the removal rate of membrane process is the maximal for all odorous compounds except for 2,3,6-trichloroanisole, followed by the advanced oxidation process as well as the traditional process. Eight odorous compounds identified in raw water were preserved after traditional treatment, while five compounds were preserved after the advanced oxidation treatment. The combined ultrafiltration and nanofiltration with pre-flocculation was more effective than either the advanced oxidation process or the traditional treating process in removing odorous compounds, and over 90% of all the odorous compounds were removed. Further investigation is required to facilitate the removal of odorous compounds from drinking water by the incorporation of ultrafiltration and nanofiltration units based on current drinking water treatments.
Afficher plus [+] Moins [-]Microhabitat variables explain patch switching by wintering Bewick’s swans through giving-up net energy intake rates Texte intégral
2020
Yu, Chao | Zhou, Lizhi | Mahtab, Nazia | Fan, Shaojun | Song, Yunwei
Microhabitat variables are determinants for animals to select forage patches and evaluate the cost/benefit tradeoffs of habitat switching. Optimal foragers would weigh habitat quality by giving-up net energy intake rate (GUN), which includes the energy intake rate and cost rate. The GUNs, energy intake rate, and cost rate can be influenced by variations in different microhabitat factors and interactive effects. In this study, we assessed the GUN patterns of wintering Bewick’s swans and the effects of microhabitat factors on their foraging strategy in three different habitats: foxnut ponds, paddy fields, and shallow lake. The foraging behaviors and microhabitat variables of the swans were investigated during the winters of 2016–2018 and 2017/2018 at Huangpi and Shengjin Lakes in Anhui Province, southeastern China. The results showed that the percentage of disturbance time and the giving-up food density in shallow water had significant negative effects on GUNs. In contrast, water depth and the giving-up food density in deep water showed positive effects on GUNs. GUNs were significantly different among the three habitats. GUNs also decreased as winter progressed. Swans would decrease their GUNs under unfavorable foraging conditions such as more disturbances; however, GUNs would increase with water depth and food availability in patches with deep water. The swans demonstrated diverse GUN patterns in different foraging habitats, driven by the tradeoffs between energy intake rates and energy cost rates that were influenced by microhabitat variables. It implies that waterbirds exposed to decreasing GUNs may mitigate energy demand and environmental stress by switching foraging habitat while in subprime foraging habitat if alternative habitats that offered higher net rates of energy gain were available.
Afficher plus [+] Moins [-]Phthalocyanine-sensitized evolution of hydrogen and degradation of organic pollutants using polyoxometalate photocatalysts Texte intégral
2020
Wang, Ruixin | Liu, Yefeng | Zuo, Peng | Zhang, Zhendong | Lei, Nana | Liu, Yaqing
In this study, 2 (3), 9 (10), 16 (17), 23 (24)-tetrakis-(8-quinoline-oxy) phthalocyanine zinc(II) (ZnQPc) was prepared and then quaternized to obtain water soluble zinc phthalocyanine (ZnQPc⁴⁺). Then, ZnQPc⁴⁺ was used as a photosensitizer for a series of POM catalysts, including Dawson type K₆[α-P₂W₁₈O₆₂]·14H₂O (P₂W₁₈) and K₁₀[α-P₂W₁₇O₆₁]·20H₂O (P₂W₁₇) and Keggine type H₃PW₁₂O₄₀·xH₂O (PW₁₂). The Keggin type PW₁₂ showed higher efficiency with 18.2 μmol of H₂ evolution (turnover number (TON) = 14,550) for 6 h upon ZnQPc⁴⁺ sensitization in relation to two Dawson P₂W₁₇ and P₂W₁₈ in a visible light–driven water-soluble system with isopropanol and H₂PtCl₆·6H₂O. In addition, the complexes of ZnQPc⁴⁺ with a series of POM catalysts (P₂W₁₇, P₂W₁₈, and PW₁₂) were also used as photocatalysts for the degradation of methylene blue (MB) in water, and it was found that the complexes of ZnQPc⁴⁺ with P₂W₁₇ and PW₁₂ showed improved photocatalytic activity, and the degradation rates of MB reached 100% at a small dosage under natural pH and visible light. The high efficacy of POM catalysts for H₂ evolution and the degradation of MB were attributed to the sensitization of POMs by ZnQPc⁴⁺, which was enabled by the transfer of photogenerated electrons of ZnQPc⁴⁺ to the lowest unoccupied molecular orbital (LUMO) of POM.
Afficher plus [+] Moins [-]Effect of gibberellic acid on growth, biomass, and antioxidant defense system of wheat (Triticum aestivum L.) under cerium oxide nanoparticle stress Texte intégral
2020
Iftikhar, Azka | Rizwan, Muhammad | Adrees, Muhammad | Ali, Shafaqat | ur Rehman, Muhammad Zia | Qayyum, Muhammad Farooq | Hussain, Afzal
Recently nanoparticles (NPs) are ubiquitous in the environment because they have unique characteristics which are the reason of their wide use in various fields. The release of NPs into various environmental compartments mainly ends up in the soil through water bodies which is a serious threat to living things especially plants. When present in soil, NPs may cause toxicity in plants which increase significance to minimize NPs stress in plants. Although gibberellic acid (GA) is one of the phytohormones that has the potential to alleviate abiotic/biotic stresses in crops plant, GA-mediated alleviation of cerium oxide (CeO₂) NPs in plants is still unknown, despite the large-scale application of CeO₂-NPs in various fields. The present study was performed to highlight the ability of foliar-applied GA in reducing CeO₂-NPs toxicity in wheat under soil exposure of CeO₂-NPs. We observed that CeO₂-NPs alone adversely affected the dry weights, chlorophyll contents, and nutrients and caused oxidative stress in plants, thereby reducing plant yield. GA coupled with CeO₂-NPs reversed the changes caused by CeO₂-NPs alone as indicated by the increase in plant growth, chlorophylls, nutrients, and yield. Furthermore, GA alleviated the oxidative stress in plants by enhancing antioxidant enzyme activities under CeO₂-NPs exposure than the NPs alone which further provided the evidence of reduction in oxidative damage in plants by GA. Overall, evaluating the potential of GA in reducing CeO₂-NPs toxicity in wheat could provide important information for improving food safety under CeO₂-NPs exposure.
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