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A highly efficient low-cost adsorbent was prepared using raw and chemically modified cellulose isolated from sugarcane bagasse for decontamination of Cr(VI) from wastewater. First, cellulose pulp was isolated from sugarcane bagasse by subjecting it to acid hydrolysis, alkaline hydrolysis and bleaching with sodium chlorate (NaClO3). Then, the bleached cellulose pulp was chemically modified with acrylonitrile monomer in the presence Fenton's reagent (Fe+2/H2O2) to carry out grafting of acrylonitrile onto cellulose by atom transfer radical polymerization. The developed adsorbent (acrylonitrile grafted cellulose) was analyzed by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Both raw cellulose and acrylonitrile grafted cellulose were used for chromium removal from wastewater. The effects of metal ion concentration, pH, adsorbent dose and time were studied, and their values were optimized. The optimum conditions for the adsorption of Cr(VI) onto raw and chemically modified cellulose were: metal ion concentration: 50 ppm, adsorbent dose: 1 g, pH: 6, and time: 60 min. The maximum efficiencies of 73% and 94% and adsorption capacities of 125.95 mg/g and 267.93 mg/g were achieved for raw and acrylonitrile grafted cellulose, respectively. High removal efficiency was achieved, owing to high surface area of 79.92 m2/g and functional active binding cites on grafted cellulose. Isotherm and kinetics studies show that the experimental data were fully fitted by the Freundlich isotherm model and pseudo first-order model. The adsorbent (acrylonitrile grafted cellulose) was regenerated using three different types of regenerating reagents and reused thirty times, and there was negligible decrease (19%) in removal efficiency after using it for 30 times. Hence, it is anticipated that acrylonitrile could be utilized as potential candidate material for commercial scale Cr(VI) removal from wastewater.
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Acrilonitrila , Celulose , Cromo , Saccharum , Águas Residuárias , Poluentes Químicos da Água , Purificação da Água , Celulose/química , Cromo/isolamento & purificação , Cromo/química , Acrilonitrila/química , Saccharum/química , Águas Residuárias/química , Adsorção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios XRESUMO
To explore the diversity and distribution characteristics of soil arbuscular mycorrhizae fungi (AMF) communities in the soft sandstone area, thirteen arsenic sandstone rock samples were collected from three planting plots (SI, SII and SIII) and one bare control plot (CK), separately. The sampling locations are as follows: the top of the slope (denoted by the number 1), sunny slope (2), shady slope (3) and gully bottom (4). These samples were then tested with an Illumina HiSeq PE250 high-throughput sequencing platform. Experimental results show that the SIII4 sample (from the gully bottom of the SIII plot) has the highest moisture content of 9.1%, while the CK sample in the control plot has lowest moisture content. SI2 has the highest pH of 9.58 and CK has the lowest pH of 8.73. SII1 has the highest available phosphorus (AP) content of 9.61 mg/kg, while SII3 has the lowest AP content of 2.29 mg/kg. Furthermore, SI2 has the highest NH4-N content of 11.24 mg/kg, while SII1 has the lowest NH4-N of 4.09 mg/kg. SII1 has the highest available potassium (AK) content of 48.92 mg/kg and CK has the lowest AK content of 1.82 mg/kg. In the observed-species index reflecting AMF genetic diversity, SI1 differences significantly from SII4 and SIII3 (P < 0.05). In the Shannon index, SI1 is significantly different from SI2, SI3, SI4; SII2 is significantly different from SII3; SI2, SI4, SII1 and SII3 are quite different from CK (P < 0.05). The dominant genera of AMF in these plots include Glomus (17.24%-65.53%), Scutellospora (0.04%-67.38%), Septoglomus (2.83%-43.03%) and Kamienskia (0.64%-46.38%). The dominant genera of AMF vary significantly between sunny slope and shady slope. Positive correlation exists between soil NH4-N and the AM fungal community structure. There are prominent positive correlations exist among genetic diversity index chao1, observed-species, pH and AP (P < 0.05), and obviously negative correlation between observed species and AK (P < 0.05). The research findings on the distribution characteristics of AM fungus community in the arsenic sandstone plot and their relationship with environmental factors can help with arsenic sandstone management in other similar areas.
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Arsênio , Glomeromycota , Micobioma , Micorrizas , Fungos/genética , Micorrizas/genética , Fósforo , Solo/química , Microbiologia do SoloRESUMO
Coal gasification is one of the most promising clean coal technologies. However, gasification process also produces a huge amount of solid waste of high carbon content, named coal gasification fine slag. The coal gasification fine slag is mainly handled by landfilling, which is not only a hazardous pollution, but also wasting the energy from residual carbon. Developing a technology to utilize coal gasification fine slag and recover the residual carbon is becoming essential for an eco-friendly coal chemical industry. In this paper, the enrichment behavior of residual carbon in coal gasification fine slag by a spiral separator is studied. The raw coal gasification fine slag sample and separator products are characterized on particle size distribution, size-depending ash content, reactivity, micromorphology and porous structure. The experimental results show that the spiral separator is efficient to remove ash and enriched carbonaceous components in coal gasification fine slag by separating feed (100%) into concentrate (81.2%), middlings (8.8%), and tailings (10.08%), where the ash content in tailings is up to 90%, accounting for 18.5% of total ash in feeding. The beneficial product "concentrate" has a good distribution of size-depending ash content, that most combustibles are enriched in these particles of diameter >100 µm. After spiral separator, the concentrate products have a more pure and developed porous structure with the surface area increasing from 199.8 m2/g (feeding) to 231.8 m2/g, as well as a better combustion reactivity of lower ignition temperature compared with feedings. Accordingly, an economic and feasible combination process of spiral separator connecting sieve can produce an enriched-carbon product of â¼45% yield and â¼80% carbonaceous content. The Iodine adsorption ability of sieved products increases by 47.6% compared with feed, and reaches up to about half of industry activated carbon. The finally sieved concentrate products have a good market prospect as fuel and adsorbent.
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BACKGROUND: Diastolic function (DF) guidelines have been simplified but lack extensive outcome data. Using a rural university heart failure (HF) database, we assessed whether DF grading could predict HF, HF readmission, and all-cause mortality (ACM). METHODS: In this single-center retrospective study that included 613 patients in sinus rhythm hospitalized for HF (HF with preserved-254 patients, with mid-range-216 patients, and reduced ejection fraction-143 patients), we recorded demographics, Doppler-echo, Framingham HF score, laboratories, HF readmission, and ACM with follow-up to 2167 days. RESULTS: Diastolic dysfunction (Ddys) parameters (left atrial volume index [LAVI] > 34 ml/m2 , tricuspid regurgitation [TR] velocity > 2.8 m/sec, and E/e' > 14) had moderate sensitivity (46.2%-65.0%) for predicting HF among all phenotypes combined with DF grading having moderate predictability and additive to a clinical composite for HF prediction (AUC = .677, P < 0.0001; difference = .043, P < 0.001) for combined phenotypes. Ddys parameters and Ddys severity (2016 ASE criteria: grade II and III) were significantly associated with HF readmission for decompensated HF within 60-2167 days of follow-up (LAVI > 34 ml/m2 : HR 1.56 [1.26-2.19]; E/e' > 14: HR 1.44 [1.21-1.99]; TR > 2.8 m/sec: H1.43 [1.19-1.88]; LV Dys grade II: HR 2.12 [1.42-2.96]; LV Ddys grade III: HR 2.39 [1.57-4.82]). CONCLUSION: The findings of this study highlight the clinical and prognostic relevance of determining the severity of LV Ddys in patients with HF with regard to HF verification and HF readmission.
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Insuficiência Cardíaca , Readmissão do Paciente , Ecocardiografia , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Estudos Retrospectivos , Volume SistólicoRESUMO
Pressurized oxy-combustion is an emerging and more efficient technology for carbon capture, utilization, and storage than the first generation (atmospheric) oxy-combustion. NOx is a major conventional pollutant produced in pressurized oxy-combustion. In pressurized oxy-combustion, the utilization of latent heat from moisture and removal of acid gases (NOx and SOx) are mainly conducted in an integrated direct-contact wash column. Recent studies have shown that NOx particular inlet concentration should be maintained before direct contact wash column to remove NOx and SOx efficiently. As a result, minimizing NOx for environmental reasons, avoiding corrosion in carbon capture, utilization, and storage, and achieving effective NOx and SOx removal in direct contact wash columns are crucial. Reburning is a capable and affordable technology for NOx reduction; however, this process is still less studied at elevated pressure, particularly in pressurized oxy-combustion. In this paper, the kinetic evaluation and optimization study on NOx reduction by reburning under pressurized oxy-combustion was conducted. First, the most suitable mechanism was selected by comparing the results of different kinetic models with the experimental data in literature at atmospheric and elevated pressures. Based on the validated mechanism, a variety of parameters were studied at high pressure, i.e., comparing the effects of oxy and the air environment, different reburning fuels, residence time, H2O concentration, CH4/NO ratio, and equivalence ratio on the NO reduction. The results show that de-NOx efficiency in an oxy environment is significantly enhanced compared to the air environment. Improvement in the de-NOx efficiency is considerably higher with a pressure increase of up to 10 atm, but the effect is less prominent above 10 atm. The formation of HCN is significantly reduced while the N2 formation is enhanced as the pressure increases from 1 to 10 atm. The residence time required for the maximum NO reduction decreases as the pressure increases from 1 atm to 15 atm. At the higher pressure, the NO reduction rises prominently when the ratio of CH4/NO increases from 1 to 2; however, the effect fades after that. At higher pressure, the NO reduction by CH4 reburning decreases as the H2O concentration increases from 0 to 35%. The optimum equivalence ratio and high pressure for maximum NO reduction are 1.5 and 10 atm, respectively. This study could provide guidance for designing and optimizing a pressurized reburning process for NOx reduction in POC systems.
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Poluentes Atmosféricos , Gases , Poluentes Atmosféricos/análise , Temperatura Alta , CinéticaRESUMO
This study aimed to determine the status of groundwater contamination with faecal coliform and nitrate in the rural areas of Mardan district, Pakistan. Both analytes require regular monitoring according to the National Environmental Quality Standards (NEQS) of Pakistan. Groundwater samples (n = 100) were collected from 25 villages across four zones. Samples were analysed for physicochemical parameters including pH, electrical conductivity (EC), Escherichia coli (E. coli) contamination, nitrite, and nitrate ([Formula: see text] and [Formula: see text]). Whilst the average concentrations of [Formula: see text] in the water samples were within the permissible limits of 50 mg L-1 set by the World Health Organisation (WHO) and NEQS two villages exceeded the safety limits. Non-carcinogenic health risks of [Formula: see text] were estimated in terms of average daily dose (ADD) and hazard quotient (HQ). The HQ values for [Formula: see text] were > 1 for children signifying potential health risks; however, the adult population had HQ < 1 which indicates no risk. Groundwater samples tested positive for E. coli contamination in 13 villages, suggesting that residents may be living at risk of various microbial diseases due to drinking of contaminated water. The findings of this study provide valuable baseline data for groundwater researchers, policymakers, and the local public health department.
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Água Potável , Água Subterrânea , Poluentes Químicos da Água , Adulto , Criança , Água Potável/análise , Monitoramento Ambiental , Escherichia coli , Humanos , Nitratos/análise , Paquistão , Medição de Risco , Poluentes Químicos da Água/análiseRESUMO
Switchable-hydrophilicity solvent liquid-liquid microextraction and dispersive liquid-liquid microextraction were compared for the extraction of piperine from Piper nigrum L. prior to its analysis by using high-performance liquid chromatography with UV detection. Under optimum conditions, limits of detection and quantitation were found as 0.2-0.6 and 0.7-2.0 µg/mg with the two methods, respectively. Calibration graphs showed good linearity with coefficients of determination (R2 ) higher than 0.9962 and percentage relative standard deviations lower than 6.8%. Both methods were efficiently used for the extraction of piperine from black and white pepper samples from different origins and percentage relative recoveries ranged between 90.0 and 106.0%. The results showed that switchable-hydrophilicity solvent liquid-liquid microextraction is a better alternative to dispersive liquid-liquid microextraction for the routine analysis of piperine in food samples. A novel scaled-up dispersive liquid-liquid microextraction method was also proposed for the isolation of piperine providing a yield of 102.9 ± 4.9% and purity higher than 98.0% as revealed by NMR spectroscopy.
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Alcaloides/análise , Benzodioxóis/análise , Cicloexilaminas/química , Etilaminas/química , Contaminação de Alimentos/análise , Microextração em Fase Líquida , Piper nigrum/química , Piperidinas/análise , Alcamidas Poli-Insaturadas/análise , Cromatografia Líquida de Alta Pressão , Interações Hidrofóbicas e Hidrofílicas , Solventes/química , Espectrofotometria Ultravioleta , Raios UltravioletaRESUMO
Oxy-combustion is one of the most promising technologies for carbon capture and sequestration. When CO2-neutral biomass is burned under oxy-combustion conditions, named "oxy-biomass combustion" a negative CO2 emission can be achieved. However, the high content of potassium and chlorine in biomass results in sever ash deposition and corrosion in air fired furnaces, which are further aggravated in oxy-combustion mode due to the enrichment of corrosive species by flue gas recycle. In this paper, the hot corrosion behaviors and mechanism of two representative materials (TP347H, HR3C) used for superheaters in furnaces are studied. The effects of oxy-combustion atmosphere, KCl deposition, effect of SO2, effect of water vapor, and temperature on the corrosion kinetics at the starting stage are investigated. The corrosion severity of the materials was determined using the weight gain method, and the microstructures and chemical compositions of corrosion layers were characterized by the scanning electron microscopy with energy dispersive spectroscopy, and X-ray diffraction. The results show that the hot corrosion rate is significantly sped up by KCl deposition, more than five times the gas corrosion rate under the same gas composition and temperature. HR3C with higher Cr and Ni contents is more likely to form Cr enrichment on the interface between the corrosion layer and the substrate than TP347H, resulting in stronger resistance to the hot corrosion than TP347H. When the corrosion atmosphere is changed from air-combustion to oxy-combustion, the hot corrosion rate is reduced with a denser Cr oxide film and less metal sulfides. The increase of temperature in the presence of KCl deposition significantly affects the hot corrosion rate, e.g. the corrosion rate at 650 °C is 16 times higher than that at 450 °C. Water vapor and SO2 concentrations have opposite influences on the hot corrosion, respectively. Compared to the dry environment, a high-humidity environment decreases the hot corrosion rate; however, a higher SO2 concentration facilitates the sulfation of KCl deposits, leading to stronger damage to the chromium oxide film and thereby an increased hot corrosion rate.
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Atmosfera , Aço Inoxidável , Biomassa , Dióxido de Carbono , Corrosão , Temperatura AltaRESUMO
Steam methane reforming (SMR) is a dominant technology for hydrogen production. For the highly energy-efficient operation, robust energy analysis is crucial. In particular, exergy analysis has received the attention of researchers due to its advantage over the conventional energy analysis. In this work, an exergy analysis based on the computational fluid dynamics (CFD)-based method was applied to a monolith microreactor of SMR. Initially, a CFD model of SMR was developed using literature data. Then, the design and operating conditions of the microreactor were optimized based on the developed CFD model to achieve higher conversion efficiency and shorter length. Exergy analysis of the optimized microreactor was performed using the custom field function (CFF) integrated with the CFD environment. The optimized catalytic monolith microreactor of SMR achieved higher conversion efficiency at a smaller consumption of energy, catalyst, and material of construction than the reactor reported in the literature. The exergy analysis algorithm helped in evaluating length-wise profiles of all three types of exergy, namely, physical exergy, chemical exergy, and mixing exergy, in the microreactor.
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Recent advancement in fermentation technologies resulted in the increased yields of recombinant proteins of biopharmaceutical and medicinal importance. Consequently, there is an important task to develop simple and easily scalable methods that can facilitate the production of high-quality recombinant protein. Most of the recent reports described the expression of recombinant human IL-1 receptor antagonist (rhIL-1Ra) in Escherichia coli using isopropyl-ß-d-thiogalacto pyranoside (IPTG), a nonmetabolizable and expensive compound, as an expression inducer. In this study, we describe the expression and one-step purification of gallbladder-derived rhIL-1Ra by autoinduction in E. coli. This method includes special media that automatically induce the target protein expression from T7 promoter and allow the production of the target protein in high yield than the conventional IPTG induction method. In addition to fermentation process improvements, one-step purification strategy is essential to make the process economical. We developed a single-step cation exchange chromatography and obtained 300 mg/L of rhIL-1Ra with 98% purity. Purified protein was characterized by SDS-PAGE and Ion exchange HPLC (IEX-HPLC). The described method can be used to scale up the production of rhIL-1Ra and other recombinant proteins.
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Expressão Gênica , Proteína Antagonista do Receptor de Interleucina 1/biossíntese , Proteína Antagonista do Receptor de Interleucina 1/química , Proteína Antagonista do Receptor de Interleucina 1/isolamento & purificação , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Proteína Antagonista do Receptor de Interleucina 1/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificaçãoRESUMO
Two hundred white leg horn layers at 70 weeks of age were induced to molt with high dietary zinc (3 g/kg of feed); thereafter, birds were equally and randomly divided (n = 50 each) into four groups keeping G1 as control (CP 16 % diet, no other supplement), G2 (CP 18 % diet), G3 (CP 16 % diet + symbiotic; Perfectin® at 85 mg/L in drinking water daily), and G4 (CP 16 % diet + probiotic; Protexin® at 85 mg/L in drinking water daily). The egg production record was maintained throughout the experiment period, and egg quality parameters were performed at 5 %, peak, and end of post molt production stage. The overall egg production was highest in G2 (74.51 %) followed by G3 (64.95 %) and G4 (65.03 %) and lowest in G1 (58.51 %). The overall egg weight, length, diameter, weight and diameter of albumin and yolk, egg shell thickness as well as egg shell breaking strength increased (P ≤ 0.01) in G2 and G3 as compared to G1. The albumin height, yolk height, yolk index, and haugh unit score decreased (P ≤ 0.01) in G2 and G3 as compared to G1. FCR/12 eggs improved in all the supplemented groups as compared to control (G1). The bacterial contamination of eggs was seen in G1. Conclusively, it was observed in the current experiment that the supplementation with protein, probiotic, and symbiotic did improve the production quality and potential in molted layers.
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Ração Animal/análise , Galinhas/fisiologia , Dieta/veterinária , Proteínas Alimentares/administração & dosagem , Oviposição/efeitos dos fármacos , Probióticos/administração & dosagem , Animais , Suplementos Nutricionais , Feminino , Paquistão , Clima TropicalRESUMO
In this study, an on-line sample preconcentration technique, field-amplified sample injection combined with water removal by electroosmotic flow (EOF) pump, was applied to realize a highly sensitive chiral analysis of ß-blocker enantiomers by MEEKC. The introduction of a water plug in capillary before the electrokinetic injection provided the effective preconcentration of chiral compounds. And then the water was moving out of the column from the injection end under the effect of the EOF, which avoided dilution of the stacked ß-blocker enantiomers concentration suffering from the presence of water in separation buffer. Moreover, the addition of H3 PO4 and methanol in the sample solution greatly improved the enhancement efficiency further. Under optimized conditions, more than 2700-fold enhancement in sensitivity was obtained for each enantiomer of bupranolol (BU), alprenolol (AL), and propranolol (PRO) via electrokinetic injection. LODs were 0.10, 0.10, 0.12, 0.11, 0.02, and 0.02 ng/mL for S-BU, R-BU, S-AL, R-AL, S-PRO, and R-PRO, respectively. Eventually, the proposed method was successfully applied to the determination of BU, AL, and PRO in serum samples with good recoveries ranging from 93.4 to 98.2%.
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Antagonistas Adrenérgicos beta/análise , Antagonistas Adrenérgicos beta/isolamento & purificação , Cromatografia Capilar Eletrocinética Micelar/métodos , Antagonistas Adrenérgicos beta/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Estereoisomerismo , Água/químicaRESUMO
The aim of the study was to find out the effect of various heat-combating systems (HCS) on the egg quality characteristics of commercial laying hens during high environmental temperature of the year. Three hundred pullets were wing banded and randomly divided into 15 experimental units comprising of 20 pullets each. These units were randomly allotted to five treatment groups, replicated thrice according to four heat-combating systems (desert cooling, water sprinkling, time limit feeding, ascorbic acid supplementation), and the control was maintained under the same housing system. The mean values of egg weight, eggshell thickness, Haugh unit, thick albumen height, yolk height, and yolk diameter were calculated. The layers kept under the influence of desert cooling produced eggs with more weight and thicker shells than those under other systems. Results of the present study did not show any difference in the shell thickness between water sprinkling and ascorbic acid supplementation as compared to the control group. Haugh unit and yolk index values obtained from the layers kept under various HCS did not significantly differ from those of the control group. All HCS significantly reduced the occurrence of blood spots in the eggs as compared to the control. All the treatments in general markedly reduced the incidence of meat spots in the eggs especially with the supplementation of ascorbic acid being the most effective. Among all of the treatments, the desert cooling system proved to be the best for producing better-quality eggs during hot periods of the year with less humidity.
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Ar Condicionado/métodos , Ácido Ascórbico/farmacologia , Galinhas/fisiologia , Ovos/normas , Temperatura Alta , Animais , Peso Corporal/efeitos dos fármacos , Suplementos Nutricionais , Casca de Ovo/efeitos dos fármacos , UmidadeRESUMO
In this digital age, promoting economic development through technology innovation and adoption has become a pressing matter, contributing to increased productivity and, in turn, carbon emissions. Consequently, this study employs a novel technique (Newey-West Standard Error Method, Technology Adaptation Model) to quantify information and communication technology (ICT) adoption rates as a proxy indicator for evaluating the Persian Gulf economy's technology development. Moreover, this study investigates the evidence of the environmental Kuznets curve, with trade openness, technological adoption, and innovation as sustainable development controls. The findings reveal that two of three technological innovation instruments, fixed telephone, and internet subscriptions, increase carbon emissions. In contrast, mobile cellular subscriptions simultaneously reduce carbon emissions in the Persian Gulf. Furthermore, measures of technology adoption, high-technology exports, and electricity use contribute to the increase in carbon emissions. Trade openness also raises carbon emissions in the Persian Gulf. These findings suggest that policymakers must develop technological innovation and adoption strategies that effectively promote a greener environment.
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Carbono , Oceano Índico , Carbono/análise , Invenções , Desenvolvimento Econômico , HumanosRESUMO
Digitalization has emerged as a new hope for low-carbon sustainable economic growth after its successful trial during the COVID-19 measures. Therefore, both developed and developing economies focus on digitalization to cope with carbon neutrality targets. Thus, this study attempted to generate a meaningful relationship between the digital economy and green energy, innovation, and environmental tax policy to capture the role of factors in acquiring carbon neutrality. For the abovementioned objectives, modern econometric methods, such as the Kilian bias-adjusted bootstrap, were adopted to evaluate the Chinese dataset between 1990 and 2021. The results indicate that the study factors play a significant role in acquiring carbon neutrality in the long-term Chinese economy. Furthermore, quantile autoregressive distributed lag model (QARDL) indicates that all the factors influence carbon neutrality in various quantiles. Consequently, the digital economy, green energy and innovation, and environmental taxes significantly assist in attaining carbon neutrality in the long term, and the ecological Kuznets curve prevails in the economy. Therefore, radical and wide-ranging policy implications are required in many areas including environmental restrictions, digital economy promotion, green and sustainable technologies, and clean energy sources.
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Impostos , Carbono , Dióxido de Carbono , China , Desenvolvimento Econômico , Política Fiscal , Política Ambiental , Desenvolvimento SustentávelRESUMO
Real-world decision-making problems often include multi-polar uncertainties dependent on multi-dimensional attributes. The m-polar fuzzy (mF) sets can efficiently handle such multi-faceted complications with T-norm based weighted aggregation techniques. The Aczel-Alsina T-norms offer comparatively flexible and accurate aggregation than the other well-known T-norm families. Consequently, this work introduced novel mF Aczel-Alsina aggregation operators (AOs), including weighted averaging (mFAAWA, mFAAOWA, mFAAHWA) and weighted geometric (mFAAWG, mFAAOWG, mFAAHWG) AOs. The fundamental properties, including boundedness, idempotency, monotonicity, and commutativity are investigated. Based on the proposed AOs, a decision-making algorithm is developed and implemented to solve two detailed multi-polar site selection problems (for desalination plant and for wind-power plant). Finally, a comparison with mF Dombi and mF Yager AOs reveals that different T-norm based AOs may yeild different solutions for the same problem.
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The growing population and urbanization have adversely affected the environment including water. The waste water from industries has affected not only human but also animals. The availability of clean water is one of the foremost needs for living organism. This makes very urgent to find reliable solutions for cleaning waste water. These days catalysis is one the best solutions to remove and degrade organic pollutants. In this work, porous composite polymer films have been designed through facile method which were employed to stabilize zero-valent metal nanoparticles (NPs). The sustainable, environmentally friendly polymer matrix with attached metal NPs was applied for the effective catalytic degradation of both phenolic compounds and organic dyes. The different composite films consist of ZnO NPs embedded in an Oxidized Alginate-Chitosan (OAlg-CS) biomatrix named as OAlg-CS/ZnO with various percentages of ZnO as a support for metallic Cu NPs. The ZnO NPs have been incorporated into OAlg-CS polymer with 10, 15, and 20 wt% and are designated as OAlg-CS/ZnO-10, OAlg-CS/ZnO-15, OAlg-CS/ZnO-20. Various analytical techniques were utilized to investigate the shape, morphology, elemental composition, functional groups and stability of the composite films. All these polymer nanocomposite films were then evaluated for removal of model organic pollutants comprising p-nitrophenol (4-NP), methylene blue (MB), and methyl orange (MO). The Kapp value for 4-NP was 2.19 × 10-1 min-1, 4.68 × 10-1 min-1 for MO and 8.99× 10-1 min-1 for MB. The experimental results demonstrated that OAlg-CS/ZnO-20 films show the highest catalytic activity as compared to OAlg-CS/ZnO, OAlg-CS/ZnO-10, and OAlg-CS/ZnO-15. The order of rate constants for nitrophenol and dyes using OAlg-CS/ZnO-20 was found to be MB Ë MO Ë 4-NP, showing the selectivity of these composite films. The prepared composite films were also investigated for their antibacterial activity against Gram-positive and Gram-negative bacteria and all the films exhibited good anti-bacterial activity, with OAlg-CS/ZnO-20 showed the highest anti-bacterial activity.
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Aiming at the limitations of single-functionality, limited-applicability, and complex designs prevalent in current metasurfaces, we propose a terahertz multifunctional and multiband tunable metasurface utilizing a VO2-metal hybrid structure. This metasurface structure comprises a top VO2-metal resonance layer, a middle polyimide dielectric layer, and a gold film reflective layer at the bottom. This metasurface exhibits multifunctionality, operating independently of polarization and incident angle. The varying conductivity states of the VO2 layers, enabling the metasurface to achieve various terahertz functionalities, including single-band absorption, broadband THz absorption, and multiband perfect polarization conversion for linear (LP) and circularly polarized (CP) incident waves. Finally, we believe that the functional adaptability of the proposed metasurface expands the repertoire of options available for future terahertz device designs.
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Staphylococcus epidermidis is an opportunistic bacterial pathogen. The study screened isolates of S. epidermidis of pediatric origin for genetic markers of discriminatory potential. 103 isolates (n = 75 clinical; n = 28 community) were screened for methicillin resistance (mecA), formate dehydrogenase (fdh) and an array of virulence factors through multiplex PCR and Congo red assay. The isolates were typed in four distinct categories, based on the presence of selected virulent factors. The type A clinical isolates carrying icaADBC operon (n = 22; 29.3%, P = 0.117) were not significantly differentiating the origin of isolates. The type B clinical isolates representing methicillin resistant S. epidermidis (MRSE) (n = 73; 97.3%, P < 0.00001) and the type C clinical isolates lacking formate dehydrogenase fdh (n = 62; 82.6%, P < 0.00001) were having significant discriminatory potential of clinical isolates, respectively. All type D community isolates were carrying fdh (n = 28; 100%, P < 0.00001). MecA and fdh are significant differential markers of pathogenicity and commensalism in S. epidermidis of pediatric origin.
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Infecções Estafilocócicas , Staphylococcus epidermidis , Criança , Humanos , Staphylococcus epidermidis/genética , Formiato Desidrogenases , Virulência/genética , Infecções Estafilocócicas/microbiologia , Paquistão , Simbiose , Antibacterianos , Proteínas de Bactérias/genéticaRESUMO
BACKGROUND: Oxytocin has been reported for a wide range of adverse effects in different species of lactating animals. The present study was aimed to evaluate the adverse effects of oxytocin on biomarkers of oxidative stress in buffaloes. Lactating buffaloes (n = 40) were randomly selected from a commercial dairy farm located in the peri-urban area of district Faisalabad, Pakistan and divided into two equal groups viz. treatment and control groups, each containing 20 buffaloes. Buffaloes in treatment group were injected with oxytocin before each milking (morning and evening) for milk let down; whereas, animals in control group were milked naturally without oxytocin injection. Both the groups were assessed for oxidative stress biomarkers. RESULTS: Results showed significantly higher levels (P ≤ 0.05) of TOS, tHcy and ceruloplasmin oxidase activity in lactating buffaloes injected with oxytocin as compared to those of control group. On the other hand, serum levels of TAS, PON1 and arylesterase were significantly lower (P ≤ 0.05) in the buffaloes of treatment group. CONCLUSIONS: Oxytocin injection in lactating buffaloes resulted in elevated oxidative stress by increasing the total homocysteine and ceruloplasmin oxidase activity and decreasing enzymatic activities of antioxidant enzymes including paraoxonase-1 and arylesterase; that might render the animals to poor productive and reproductive potential.