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Volatile oils or essential oils (EOs) were extracted from three V. sebifera samples (labeled as A, B, and C) in September 2018 and February 2019; the extraction process involved hydrodistillation of the leaves. The chemical compositions of the EOs were analyzed using gas chromatography-mass spectrometry (GC/MS). The volatile components were identified by comparing their retention indices and mass spectra with standard substances documented in the literature (ADAMS). The antioxidant activity of the EOs was evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH), while their toxicity was assessed using Artemia salina Leach. Molecular docking was utilized to examine the interaction between the major constituents of V. sebifera EO and acetylcholinesterase (AChE), a molecular target linked to toxicity in A. salina models. The EO obtained from specimen A, collected in September 2018, was characterized by being primarily composed of (E,E)-α-farnesene (47.57%), (E)-caryophyllene (12.26%), and α-pinene (6.93%). Conversely, the EO from specimen A, collected in February 2019, was predominantly composed of (E,E)-α-farnesene (42.82%), (E)-caryophyllene (16.02%), and bicyclogermacrene (8.85%), the EO from specimen B, collected in September 2018, primarily contained (E,E)-α-farnesene (47.65%), (E)-caryophyllene (19.67%), and α-pinene (11.95%), and the EO from the leaves collected in February 2019 was characterized by (E,E)-α-farnesene (23.57%), (E)-caryophyllene (19.34%), and germacrene D (7.33%). The EO from the leaves collected in September 2018 contained (E,E)-α-farnesene (26.65%), (E)-caryophyllene (15.7%), and germacrene D (7.72%), while the EO from the leaves collected in February 2019 was primarily characterized by (E,E)-α-farnesene (37.43%), (E)-caryophyllene (21.4%), and α-pinene (16.91%). Among these EOs, sample B collected in February 2019 demonstrated the highest potential for inhibiting free radicals, with an inhibition rate of 34.74%. Conversely, the EOs from specimen A exhibited the highest toxic potentials, with an lethal concentration 50 (LC50) value of 57.62 ± 1.53 µg/mL, while specimen B had an LC50 value of 74.72 ± 2.86 µg/mL. Molecular docking results suggested that hydrophobic interactions significantly contributed to the binding of the major compounds in the EO from sample B to the binding pocket of AChE.
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Antioxidantes , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Animais , Artemia/efeitos dos fármacos , Simulação de Acoplamento Molecular , Folhas de Planta/química , Acetilcolinesterase/metabolismoRESUMO
Female infertility (FI) is a global health issue. Polycystic ovary syndrome (PCOS) is a common cause of FI. The renalase gene (RNLS) is associated with FI and other human diseases. Based on the documented missense variants, rs6166 and rs2296545 single-nucleotide polymorphisms (SNPs) were not identified in Saudi women with FI and PCOS. This study aimed to investigate the molecular role of the two SNPs in Saudi women with FI and PCOS. In this cross-sectional study, 96 healthy controls, 96 women with FI, and 96 women with PCOS were recruited. DNA was isolated, and polymerase chain reactions and Sanger sequencing analysis were performed using rs6166 and rs2296545 SNPs. The data obtained from the three groups were used to perform statistical analyses based on genotype, allele frequencies, regression models, and ANOVA analysis. Both rs6166 and rs2296545 had no role in FI or PCOS in Saudi women. A predicted reason for non-association in Saudi women could be the role of elderly women in the controls compared with women with FI and PCOS. Moreover, age, weight, and body mass index were higher in the control group than the FI and PCOS groups. In conclusion, rs6166 and rs2296545 SNPs were not associated with FI or PCOS in Saudi women.
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Soil erosion is a serious and complex environmental problem worldwide, especially in the centre west of Tunisia. Whereas the construction of hill reservoirs is part of the soil and water conservation strategy, many of these have a siltation problem. Dhkekira is one of the smallest watersheds in central Tunisia whose most lithological formation consists of materials that are quite susceptible to water erosion. Due to the lack of low-scale lithological data, digital IR aerial photos with 2 m spatial resolution were considered. A semi-automatic classification of aerial photos, based on the image's textural indices is developed. The lithologic map extracted from aerial photos was used as input for ANSWERS-2000 water erosion model. Results obtained indicate first, with the semi-automatic classification of the mean and standard deviation of the thumbnail histograms that image output could help to give an idea about the existence of some surface lithological formation. The model applied to Dhkekira watershed showed that the spatial difference in water erosion was not caused only by land cover and slope, but also by lithological formation. The percentage of each lithological formation in sediment yield at the Dhkekira hill reservoir was estimated to be 69% sediment yield from Pleistocene and 19.7% from Lutetian-Priabonian.
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Recuperação e Remediação Ambiental , Erosão do Solo , Conservação dos Recursos Naturais/métodos , Água , Monitoramento Ambiental/métodos , SoloRESUMO
The risk assessment of trace elements has received substantial attention for the achievement of UN Sustainable Developmental Goals (UN-SDGs). The present study aimed to evaluate health and ecological risks associated with trace element accumulation in Brassica oleracea under wastewater irrigations from three different areas. This study, for the first time, compared the pros and cons of mixed water crop irrigation (wastewater with fresh/groundwater). A pot experiment was conducted to evaluate the buildup of eight trace elements (As, Cu, Cd, Mn, Fe, Pb, Ni and Zn) in soil and B. oleracea plants irrigated with wastewater alone and mixed with fresh/groundwater. Specific ecological [degree of contamination (Cd), potential ecological risk index (PERI), pollution load index (PLI), geo-accumulation index (Igeo)], phytoaccumulation [bioconcentration factor (BCF) and transfer factor (TF)] and health risk models [chronic daily intake (CDI), hazard quotient (HQ), cancer risk (CR)] were applied to assess the overall contamination of trace elements in the soil-plant-human system. Moreover, these indices were compared with the literature data. The concentration of Cd, Fe and Mn exceeded the threshold limits of 10, 500 and 200 mg kg-1, respectively, for agricultural soil. Overall, all the irrigation waters caused significant pollution load in soil indicating high ecological risk (Cd > 24, PERI > 380, Igeo > 5, PLI > 2). Not all the mixing treatments caused a reduction in trace element buildup in soil. The mixing of wastewater-1 with either groundwater or freshwater increased trace element levels in the soil as well as risk indices compared to wastewater alone. The BCF and TF values were > 1, respectively, for 66% and 7% treatments. Trace element concentration in plants and associated health risk were minimized in mixed wastewater treatments. There were 22% and 32% reduction in HQ and CR when wastewater was mixed with freshwater and 29% and 8% when mixed with groundwater. Despite total reduction, a great variation in % change in risk indices was observed with respect to the area of wastewater collection. Therefore, mixed water irrigation may be a good management strategy, but its recommendation depends on soil properties and composition of waters used for mixing. Moreover, it is recommended that the freshwater and wastewater of the particular area may be continuously monitored to avoid potential associated health hazards.
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Brassica , Metais Pesados , Poluentes do Solo , Oligoelementos , Humanos , Águas Residuárias , Solo , Monitoramento Ambiental/métodos , Oligoelementos/análise , Cádmio , Metais Pesados/análise , Poluentes do Solo/análise , Medição de Risco , ÁguaRESUMO
Water contamination by arsenic (As) is widespread and is posing serious health threats globally. Hence, As removal techniques/adsorbents need to be explored to minimize potentials hazards of drinking As-contaminated waters. A column scale sorption experiment was performed to assess the potential of three biosorbents (tea waste, wheat straw and peanut shells) to remove As (50, 100, 200 and 400 µg L-1) from aqueous medium at a pH range of 5-8. The efficiency of agricultural biosorbents to remove As varies greatly regarding their type, initial As concentration in water and solution pH. It was observed that all of the biosorbents efficiently removed As from water samples. The maximum As removal (up to 92%) was observed for 400 µg L-1 initial As concentration. Noticeably, at high initial As concentrations (200 and 400 µg L-1), low pH (5 and 6) facilitates As removal. Among the three biosorbents, tea waste biosorbent showed substantial ability to minimize health risks by removing As (up to 92%) compared to peanut shells (89%) and wheat straw (88%). Likewise, the values of evaluated risk parameters (carcinogenic and non-carcinogenic risk) were significantly decreased (7-92%: average 66%) after biosorption experiment. The scanning electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray and X-ray diffraction analyses confirmed the potential of biosorbents to remediate As via successful loading of As on their surfaces. Hence, it can be concluded that synthesized biosorbents exhibit efficient and ecofriendly potential for As removal from contaminated water to minimize human health risk.
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Arsênio , Poluentes Químicos da Água , Purificação da Água , Humanos , Arsênio/análise , Adsorção , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Água , Medição de Risco , Chá , Cinética , Concentração de Íons de HidrogênioRESUMO
This study addresses the significance of wastewater recuperation by a simple and facile treatment process known as photocatalyst technology using visible light. Titanium di-oxide (TiO2) is the most promising photocatalyst ever since longing decades, has good activity under UV light, owing to its small band gap. Hence, TiO2 has been modified with metal oxides for the positive response against visible light. Since this is an efficient process, the novelty has been made on nanometal oxide CdO (cadmium oxide) combined with TiO2 to acquire the best efficiency of degrading organic chlorophenol contaminant. Initially, the composites were synthesized by sol-gel and thermal decomposition methods and investigated for their various outstanding properties. The characterized outcomes have exhibited heterostructures with reduced crystallite size from the X-ray diffraction studies. Then, the determination of nanoporous feature was recognized through HR-TEM analysis which was also detected with some dislocations. The EDX spectrum was identified the perfect elemental composition. The nitrogen adsorption-desorption equilibrium was attained that offers many pores measured with high surface area. The XPS result convinced that Ti3+ was accessible along with TIO2/CdO composite. Further the absorption towards higher wavelength was obtained from UV-vis spectra. Finally, for the photocatalytic application of chlorophenol, the composite shows higher percentage of degrading efficiencies than the pristine TiO2. The photocatalytic mechanism was discussed in detail.
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Clorofenóis , Poluentes Ambientais , Nanoporos , Catálise , Clorofenóis/química , Óxidos/química , Titânio/químicaRESUMO
The capacity to generate a constant signal response from an enzyme on an electrode surface has been a fascinating topic of research from the past three decades. To nourish the enzymatic activity during electrochemical reactions, the immobilization of dual enzymes on the electrode surface could prevent the enzymatic loss without denaturation and thus long-term stability can be achieved. For effective immobilization of dual enzymes, mesoporous materials are the ideal choice because of its numerous advantages such as 1. The presence of porous structure facilitates high loading of enzymes 2. The formation of protective environment can withstand the enzymatic activity even at acidic or basic pH values and even at elevated temperatures. Herein, we develop bienzymatic immobilization of horseradish peroxidase (HRP) and cholesterol oxidase (ChOx) on mesoporous V2O5-TiO2 based binary nanocomposite for effective sensing of hydrogen peroxide (H2O2) in presence of redox mediator hydroquinone (HQ). The utilization of redox mediator in second-generation biosensing of H2O2 can eliminate the interference species and reduces the operating potential with higher current density for electrochemical reduction reaction. Using this mediator transfer process approach at HRP/ChOx/V2O5-TiO2 modified GC, the H2O2 can be determined at operating potential (-0.2 V) with good linear range (0.05-3.5 mM) higher sensitivity (1040 µAµM-1 cm-2) and lower detection limit of about 20 µM can be attained, which is due to higher mediation of electrons were transferred to the enzyme cofactors. These interesting characteristics could be due to mesoporous structure of V2O5-TiO2 can induce large immobilization and facilitate higher interaction with enzymes for wide range of biosensing applications.
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Técnicas Biossensoriais , Peróxido de Hidrogênio , Colesterol Oxidase , Coenzimas , Enzimas Imobilizadas/química , Peroxidase do Rábano Silvestre/química , Peróxido de Hidrogênio/química , Hidroquinonas , TitânioRESUMO
BACKGROUND: Quercetin (QR), is a polyphenolic flavonoid compound which is found in large amounts in certain foods, and protects against oxidative stress. The current study was conducted to determine whether Quercetin can possibly exert hepatoprotective and antioxidant activity against acrylamide (ACR) induced toxicity in rats. METHODS: Four groups of Wistar rats consisting of six rats each: (i) control group; (ii) ACR treated group (50 mg/kg bw); (iii) QR group: rats were treated with QR (10 mg/kg bw); (iv) QR (10 mg/kg bw) was given i.p. for 5 days followed by ACR (50 mg/kg bw) on 5th day (single dose). RESULTS: ACR caused an elevation in 8-OH guanosine level and a reduction in Glutahione S-transferase (GST) activity. Administration of QR significantly protected liver tissue against hepatotoxic effect of acrylamide from amelioration of the marker enzyme (p < 0.05) and DNA damage (p < 0.01) as evident by comet assay and, besides some indices of histopathological alterations. CONCLUSION: It is concluded that QR could protect the liver against DNA damage induced by ACR probably is thus capable of ameliorating ACR-induced changes in the rat livers.
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Acrilamida/toxicidade , Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Quercetina/farmacologia , Animais , Antioxidantes/química , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Fígado/citologia , Fígado/efeitos dos fármacos , Masculino , Quercetina/química , Ratos , Ratos WistarRESUMO
Context Quercetin (QE), a bioflavonoid present abundantly in fruits and vegetables, has been reported to possess antioxidant properties. Acrylamide (ACR) is formed in foods during cooking and is known to be neurotoxic. Objective The present study was designed to evaluate the protective effect of QE against neurotoxicity induced by ACR. Materials and methods Four groups of Wistar rats consisting of six rats each: (i) control group; (ii) acrylamide treated group (50 mg/kg body weight as single dose); (iii) quercetin group: rats were treated intraperitoneally (i.p.) with QE (10 mg/kg body weight alone every day for 5 d); (iv) quercetin + acrylamide group: quercetin (10 mg/kg bw) was given i.p. every day for 5 d followed by acrylamide i.p. injection (50 mg/kg bw) on fifth day (single dose). Rats were killed after 48 h. Results Administration of ACR (50 mg/kg bw) in Wistar rats resulted in significant increase of dopamine, interferon-γ and 8-hydroxyguanosine with concomitant decrease of serotonin (p < 0.001) in the rat brain. Treatment of rats with QE intraperitonealy (10 mg/kg body weight) before ACR assault resulted in the diminution of ACR-mediated neurotoxicity as evident from decreased levels of dopamine, interferon-γ (p < 0.001) and 8-hydroxyguanosine with concomitant restoration of serotonin levels (p < 0.001). Discussion and conclusion On the basis of the above results, the present study suggests that quercetin may be a potential therapeutic agent for restoration of oxidative damage to neurons.
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Acrilamida , Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Quercetina/farmacologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Citoproteção , Modelos Animais de Doenças , Dopamina/metabolismo , Feminino , Guanosina/análogos & derivados , Guanosina/metabolismo , Interferon gama/metabolismo , Masculino , Neurônios/metabolismo , Neurônios/patologia , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Ratos Wistar , Serotonina/metabolismoRESUMO
Polymer-like dielectrics with superb thermal conductivity as well as high dielectric properties hold great promise for the modern electronic field. Nevertheless, integrating these properties into a single material simultaneously remains problematic due to their mutually limited physical connotations. In this study, we developed high-quality thermally conductive epoxy composites with excellent dielectric properties. This was achieved by incorporating surface-functionalized microscale hexagonal boron nitride (BN) along with N-[3-(Trimethoxysilyl)propyl]ethylene diamine (DN) and N-[3-(Trimethoxysilyl)propyl]aniline (PN). In the resulting epoxy composite, microscale BN serves as the primary building block for establishing the thermally conductive network, while silica particles act as bridges to regulate heat transfer and reduce interfacial phonon-scattering. The prepared composites were thoroughly examined across various filler contents (ranging from 10 to 80 wt%). Among them, the DNBN/epoxy composite exhibited higher thermal conductivity (in-plane: 47.03 W m-1 K-1) at 60 wt% filler content compared to BN/epoxy (39.40 W m-1 K-1) and PNBN/epoxy (33 W m-1 K-1) composites. These results highlight the usefulness of surface modification of BN in improving compatibility between fillers and epoxy, ultimately reducing composite viscosity. Furthermore, the DNBN/epoxy composite at 60 wt% demonstrated superb dielectric constant (â¼6.15) without compromising on dissipation loss (â¼0.06). The strategy adopted in this study offers significant insights into designing dielectric thermally conductive composites with superior performance outcomes.
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Municipal wastewater is ubiquitously laden with myriad pollutants discharged primarily from a combination of domestic and industrial activities. These heterogeneous pollutants are threating the natural environments when the traditional activated sludge system fails sporadically to reduce the pollutants' toxicities. Besides, the activated sludge system is very energy intensive, bringing conundrums for decarbonization. This research endeavoured to employ Chlorella vulgaris sp. In converting pollutants from municipal wastewater into hydrogen via alternate light and dark fermentative process. The microalgae in attached form onto 1 cm3 of polyurethane foam cubes were adopted in optimizing light intensity and photoperiod during the light exposure duration. The highest hydrogen production was recorded at 52 mL amidst the synergistic light intensity and photoperiod of 200 µmolm-2s-1 and 12:12 h (light:dark h), respectively. At this lighting condition, the removals of chemical oxygen demand (COD) and ammoniacal nitrogen were both achieved at about 80%. The sustainability of microalgal fermentative performances was verified in recyclability study using similar immobilization support material. There were negligible diminishments of hydrogen production as well as both COD and ammoniacal nitrogen removals after five cycles, heralding inconsequential microalgal cells' washout from the polyurethane support when replacing the municipal wastewater medium at each cycle. The collected dataset was finally modelled into enhanced Monod equation aided by Python software tool of machine learning. The derived model was capable to predict the performances of microalgae to execute the fermentative process in producing hydrogen while subsisting municipal wastewater at arbitrary photoperiod. The enhanced model had a best fitting of R2 of 0.9857 as validated using an independent dataset. Concisely, the outcomes had contributed towards the advancement of municipal wastewater treatment via microalgal fermentative process in producing green hydrogen as a clean energy source to decarbonize the wastewater treatment facilities.
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Compostos de Amônio , Chlorella vulgaris , Microalgas , Águas Residuárias , Esgotos , Fotoperíodo , Nitrogênio , Hidrogênio , BiomassaRESUMO
The synthesis of nanosized Ag+/Fe2+ codoped hydroxyapatite (HAp) nanocomposite materials with antibacterial and anticancer characteristics is highly attractive for advancing the development of biological applications. The objective of this study was to evaluate the antibacterial and anticancer characteristics of Ag+/Fe2+ codoped hydroxyapatite materials. We developed a facile chemical precipitation method for the fabrication of Ag+/Fe2+:HAp nanocomposites. The developed Ag+/Fe2+:HAp nanocomposite materials were characterized with Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM). For measuring the size of Ag+/Fe2+:HAp nanocomposites, dynamic light scattering (DLS) is an advantageous method. The chemical states and chemical composition of Ag+/Fe2+:HAp were observed by X-ray photoelectron spectroscopy (XPS) analysis. In addition, the antibacterial efficacy of Ag+/Fe2+:HAps against Gram-positive (S.aureus), and Gram-negative (S.typhi, and E.Coli) microorganisms is examined in this current study. Ag+/Fe2+:HAp nanocomposite materials have been evaluated for biological toxicity in vitro, and the results showed that the particles were excellent at identifying and killing cancer cells. In this respect, Ag+/Fe2+:HAp nanocomposites significantly impact human colon cancer cells (HT29) while have no effect on normal fibroblast cells (L929).
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Durapatita , Nanocompostos , Humanos , Durapatita/química , Nanocompostos/química , Antibacterianos/química , Escherichia coli , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureusRESUMO
In the current study, we successfully used strychnos potatorum polysaccharide through autoclaving to synthesize palladium nanoparticles in a green, sustainable process. These polysaccharide act as a stabilizing, capping, and reducing agent. It also used various analytical characterizations, including UV-Visible spectroscopy, FT-IR spectroscopy, X-Ray diffraction (XRD), Scanning electron microscopy (FE-SEM), EDAX, and X-ray photoelectron spectroscopy (XPS), TEM and gel permeation chromatography (GPC) are used to analyze biosynthesized pallidum nanoparticles (PdNPs). The surface plasmon resonance (SPR) band at 276 nm and UV-visible spectroscopy revealed the presence of the generated PdNPs. The XRD data show that PdNPs have crystalline behavior and a pristine face-centered cubic (FCC) structure. The PdNPs were successfully developed by catalytic reduction of 4-nitrophenol (4-NP). The catalytic activity and reusability of the environmentally friendly PdNPs catalyst were demonstrated by achieving a remarkable transformation of 95 % nitrophenol to 4-aminophenol after five cycles. The reaction rate constant (k) for the degradation of 4-nitrophenol (4-NP) using SP-PdNPs as a catalyst is 0.1201 min-1 and R2 0.9867, with a normalized rate constant of (Knor = K/m) of 7.206 s-1 mM-1. These findings provide fundamental knowledge of the catalytic process governing the hydrogenation of p-nitrophenol, which will help designers of effective catalysts. An innovative and affordable technique for creating PdNPs that are environmentally acceptable and can be utilized as effective catalysts in environmental applications is the use of strychnos potatorum gum polysaccharide. The green-synthesized PdNPs can be used for pollutant remediation, including pharmaceutical, domestic, heavy metal, industrial, and pesticide pollutants.
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Nanopartículas Metálicas , Strychnos , Nanopartículas Metálicas/química , Paládio/química , Hidrogenação , Espectroscopia de Infravermelho com Transformada de Fourier , Nitrofenóis/química , Catálise , PolissacarídeosRESUMO
The effects of diabetes can be divided into short, medium and long term and various human organ systems can be effected. The present study aimed to determine how much the duration of diabetes mellitus (DM) affect the reparative ability of the body, immune response and the development of DM complications. Interleukin 1-ß (IL-1ß) and Interleukin 6 (IL-6) were monitored as specific indicators of inflammatory reaction and C-reactive protein (CRP), leukocyte count (WBC) and sedimentation rate (ESR) as general markers of inflammatory reaction. Tumour necrosis factor α (TNF-α) and transforming growth factor ß1 (TGF-ß1) were observed as indicators of reparative ability and polyneuropathy. All interleukins were determined by ELISA and evaluated spectrophotometrically. Michigan Neuropathy Screening Instrument (MNSI) is performed for neuropathy examination. Patients with diabetes mellitus were divided into 3 groups, according to duration of diabetes mellitus. IL-6 levels correlated with clinical stage of diabetic polyneuropathy at p = 0.025 R = 0.402; with CRP at p = 0.0001, R = 0.784 as well as correlation of CRP and MNSI score (R = 0.500, p = 0.034) in a group of patients with DM lasting up to 10 years. The reparative ability of the body is reduced by physiological age and ages of DM duration. The immune response is weakened in DM additionally. The dual activity of cytokines IL-6 and TGF-ß1 is present in long-duration Diabetes Mellitus.
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We represent the results of a study on as the chelators used in the environmentally friendly electroless deposition bath changed depending on the amounts of hydroxides were present. The baths were prepared using polyhydroxides, glycerol and sorbitol, as chelators with copper methanesulfonate as the metal ion. Dimethylamine borane (DMAB) was used as the reducing agent with N-methylthiourea and cytosine, as additives in both the glycerol and sorbitol contained baths. Potassium hydroxide was used as the pH adjuster, with glycerol and sorbitol baths maintained at a pH of 11.50 and 10.75 respectively at a room temperature of 28 ± 2 °C. XRD, SEM, AFM, cyclic voltammetry studies, Tafel and Impedance studies, as well as additional methods, were employed to monitor and record the surface, structural, and electrochemical characteristics of the deposits and bath. The reports of the study gave interesting results, which clearly the effect of chelators on additives in the nano deposition of copper in an electroless deposition bath.
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Quelantes , Cobre , Cobre/química , GlicerolRESUMO
Inorganic perovskite materials are possible candidates for conversion of solar energy to electrical energy due to their high absorption coefficient. Perovskite solar cells (PSCs) introduced a new type of device structure that has attention due to better efficiencies and interest in PSCs that has been increasing in recent years. Halide perovskite materials such as CsPbIBr2 show remarkable optical and structural performance with their better physical properties. Perovskite solar cells are a possible candidate to replace conventional silicon solar panels. In the present study, CsPbIBr2 perovskite materials' thin films were prepared for light-absorbing application. Five thin films were deposited on the glass substrates by subsequent spin-coating of CsI and PbBr2 solutions, subsequently annealed at different temperature values (as-deposited, 100, 150, 200 and 250 °C) to get CsPbIBr2 thin films with a better crystal structure. Structural characterizations were made by using X-ray diffraction. CsPbIBr2 thin films were found to be polycrystalline in nature. With increasing annealing temperature, the crystallinity was improved, and the crystalline size was increased. Optical properties were studied by using transmission data, and by increasing annealing temperature, a small variation in optical band gap energy was observed in the range of 1.70-1.83 eV. The conductivity of CsPbIBr2 thin films was determined by a hot probe technique and was found to have little fluctuating response toward p-type conductivity, which may be due to intrinsic defects or presence of CsI phase, but a stable intrinsic nature was observed. The obtained physical properties of CsPbIBr2 thin films suggest them as a suitable candidate as a light-harvesting layer. These thin films could be an especially good partner with Si or other lower band gap energy materials in tandem solar cells (TSC). CsPbIBr2 material will harvest light having energy of â¼1.7 eV or higher, while a lower energy part of the solar spectrum will be absorbed in the partner part of the TSC.
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The traditional definition of gestational diabetes mellitus (GDM) is the leading cause of carbohydrate intolerance in hyperglycemia of varying severity, with onset or initial detection during pregnancy. Previous studies have reported a relationship among obesity, adiponectin (ADIPOQ), and diabetes in Saudi Arabia. ADIPOQ is an adipokine that is produced and secreted by adipose tissue involved in the regulation of carbohydrate and fatty acid metabolism. This study investigated the molecular association between rs1501299, rs17846866, and rs2241766 single-nucleotide polymorphisms (SNPs) in ADIPOQ and GDM in Saudi Arabia. Patients with GDM and control patients were selected, and serum and molecular analyses were performed. Statistical analyses were performed on clinical data, Hardy Weinberg Equilibrium, genotype and allele frequencies, multiple logistic regression, ANOVA, haplotype, linkage disequilibrium, as well as MDR and GMDR analyses. The clinical data showed significant differences in various parameters between the GDM and non-GDM groups (p < 0.05). In GDM women with alleles, genotypes, and different genetic models, the rs1501299 and rs2241766 SNPs showed a strong association (p < 0.05). Multiple logistic regression analysis revealed a negative correlation (p > 0.05). This study concluded that rs1501299 and rs2241766 SNPs were strongly associated with GDM in women in Saudi Arabia.
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Biochar is a soil amendment that can change soil's physical and hydraulic properties. However, biochar application is far from being a 'one size fits-all' approach. The impact of the management practices is dependent on biochar type (feedstock and production conditions), application depth and method, climate and site characteristics. Hence, this study aims to enrich the available inconclusive information on how biochar could affect clay loamy soil and to assess the potential impact of the induced change on water stress mitigation of rain-fed durum wheat under the specific condition of the semi-arid environment of North West of Tunisia. A field experiment was investigated in which three biochar rates 0 (B0), 10 (equivalent to 0.5% of weight) (B1) and 20 t/ha (equivalent to 1% of weight), (B2), were tested. Other laboratory analysis allowed the evaluation of soil water retention curve (SWRC), saturated hydraulic conductivity (Ks), dry density (ρb) and biostress biomarkers such as glutathione-S-transferase (GST), catalase activities (CAT) and malondialdehyde content (MDA) as well as yield attributes. Results showed that treatment B2 significantly decreased ρb and Ks with relative change values of about -3.1% and -19%. Consequently, SWRC showed a better water retention capacity, mostly from saturation to matric potential value (h) of 33 kPa. Total (TAWC), plant (PAWC) and readily (RAWC) available water contents, significantly increased under B2 with relative changes of +6%, +44% and +44% respectively. Moreover, GST and CAT were also boosted under B2. Consequently, biological and grain yields as well as grain water use efficiency (GWUE) significantly increased. GWUE increased from 0.81 ± 0.04 in B0 to 1.09 ± 0.01 kg/m3 in B2. The correlation analysis showed a significant and positive correlation, between GWUE and soil water parameters (θs, θfc and θmre) suggesting the indirect effect of biochar on water-use efficiency for grain yield of wheat. Therefore, among the tested rates 20 t/ha could be suggested to improve plant soil water availability and reduce the harmful impact of drought stress on rain-fed durum wheat.
Assuntos
Antioxidantes , Desidratação , Carvão Vegetal/farmacologia , Solo , Produtos Agrícolas , Grão ComestívelRESUMO
The issue of water contamination by heavy metal ions as highly persistent pollutants with harmful influence primarily on biological systems, even in trace levels, has become a great environmental concern globally. Therefore, there is a need for the use of highly sensitive techniques or preconcentration methods for the removal of heavy metal ions at trace levels. Thus, this research investigates a novel approach by examining the possibility of using pomegranate (Punica granatum) peel layered material for the simultaneous preconcentration of seven heavy metal ions; Cd(II), Co(II), Cr(III), Cu(II), Mn(II), Ni(II) and Pb(II) from aqueous solution and three river water samples. The quantification of the heavy metals was performed by the means of FAAS technique. The characterization of biomaterial was performed by SEM/EDS, FTIR analysis and pHpzc determination before and after the remediation process. The reusability study as well as the influence of interfering ions (Ca, K, Mg, Na and Zn) were evaluated. The conditions of preconcentration by the column method included the optimization of solution pH (5), flow rate (1.5 mL/min), a dose of biosorbent (200 mg), type of the eluent (1 mol/L HNO3), sample volume (100 mL) and sorbent fraction (<0.25 mm). The biosorbent capacity ranged from 4.45 to 57.70 µmol/g for the investigated heavy metals. The practical relevance of this study is further extended by novel data regarding adsorbent cost analysis (17.49 $/mol). The Punica granatum sorbent represents a highly effective and economical biosorbent for the preconcentration of heavy metal ions for possible application in industrial sectors.
Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes Químicos da Água , Poluentes Ambientais/análise , Metais Pesados/análise , Água , Indicadores e Reagentes/análise , Água Doce , Poluentes Químicos da Água/análise , Adsorção , Concentração de Íons de HidrogênioRESUMO
Organochlorine pesticides (OCPs) have been used extensively as insecticides and herbicides. This study investigates the occurrence of lindane in surface water from the Peshawar valley (i.e., Peshawar, Charsadda, Nowshera, Mardan and Swabi districts of Khyber Pakhtunkhwa, Pakistan). Out of 75 samples tested (i.e., 15 samples from each district), 13 samples (including 2 from Peshawar, 3 from Charsadda, 4 from Nowshera, 1 from Mardan, and 3 from Swabi) are found to be contaminated with lindane. Overall, the detection frequency is 17.3%. The maximum concentration of lindane is detected in a water sample from Nowshera and found to be 2.60 µg L-1. Furthermore, the degradation of lindane in the water sample from Nowshera, containing the maximum concentration, is investigated by simulated solar-light/TiO2 (solar/TiO2), solar/H2O2/TiO2 and solar/persulfate/TiO2 photocatalysis. The degradation of lindane by solar/TiO2 photocatalysis is 25.77% after 10 h of irradiation. The efficiency of the solar/TiO2 process is significantly increased in the presence of 500 µM H2O2 and 500 µM persulfate (PS) (separately), represented by 93.85 and 100.00% lindane removal, respectively. The degradation efficiency of lindane is lower in natural water samples as compared to Milli-Q water, attributed to water matrix effect. Moreover, the identification of degradation products (DPs) shows that lindane follows similar degradation pathways in natural water samples as the one in Milli-Q water. The results show that the occurrence of lindane in surface waters of Peshawar valley is a matter of great concern for human beings and the environment. Interestingly, H2O2 and PS assisted solar/TiO2 photocatalysis is an effective method for the removal of lindane from natural water.