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1.
Bioresour Technol ; 403: 130848, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38761868

RESUMEN

This study addresses membrane biofouling in membrane bioreactors (MBRs) by exploring fungal-to-bacterial quorum quenching (QQ) strategies. While most research has been focused on bacterial-to-bacterial QQ tactics, this study identified fungal strain Vanrija sp. MS1, which is capable of degrading N-acyl-homoserine lactones (signaling molecules of Gram-negative bacteria). To determine the benefits of fungal over bacterial strains, after immobilization on fluidizing spherical beads in an MBR, MS1 significantly reduced the fouling rate by 1.8-fold compared to control MBR, decreased extracellular polymeric substance levels in the biofilm during MBR operation, and favorably changed microbial community and bacterial network, resulting in biofouling mitigation. It is noteworthy that, unlike Rhodococcus sp. BH4, MS1 enhanced QQ activity when switching from neutral to acidic conditions. These results suggest that MS1 has the potential for the effective treatment of acidic industrial wastewater sources such as semiconductor and secondary battery wastewater using MBRs.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124191, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38565046

RESUMEN

The facilegreen synthesis techniqueis becoming more and more important, and it has been proposed as a potential substitute for chemical techniques. The current study describes a low-cost, environmentally friendly method for producing tungsten trioxide (WO3) and tantalum (Ta) doped WO3nanoparticles that uses 15 % (w/v) Azadirachta indica (Neem) leaf extract and different concentrations of Ta dopant (1 to 5 %) due to its well-matched ionic radius with WO3. Various techniques FESEM, TEM, EDX, BET, UV-Vis and PL, XRD, and FTIR were used to illustrate the morphological, elemental, optical, structural, and vibrational analysis of the synthesized nanoparticles respectively. Interestingly, the band gap was significantly reduced to 1.88 eV by the addition of a dopant element. For 3 % Ta/WO3, the average particle size was also reduced to 31.6 nm. The synthesized WO3nanoparticles employed in the current study have been used for photocatalytic activitypurposes. Methylene blue (MB), one of the principal water pollutants, was degraded more quickly by the synthesized Ta/WO3nanoparticles when exposed to UV radiation. Among them, 3 % Ta/WO3 gives significantly higher photodegradation 89 % attributed to the Burstein-Moss effect. The significant output of optimized nano-photocatalyst has been observed from the trapping experiment and reusability test. Furthermore, Zeta potential and TOC analysis have been taken to check the stability and mineralization performance. Additionally, the results of the simulation that was carried out using the finite element analysis approach in the RF module of COMSOL Multiphysics 5.3a are quite similar to the experimental findings. This simulation method made it easier for readers to understand the numerous aspects of the photocatalytic process that has been discussed here.

3.
RSC Adv ; 14(10): 7040-7051, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38414992

RESUMEN

Gas sensing technology has a broad impact on society, ranging from environmental and industrial safety to healthcare and everyday applications, contributing to a safer, healthier, and more sustainable world. We studied pure and Fe-decorated hexagonal boron nitride (h-BN) gas sensor for monitoring of carbon-based gases using density functional theory (DFT). The calculations utilized the Generalized Gradient Approximation with the Perdew-Burke-Ernzerhof (GGA-PBE) exchange-correlation functional. The novelty of our study lies in the investigation of the adsorption of harmful gases such as carbonyl sulfide, carbinol, carbimide, and carbonyl fluoride on both pure and Fe-decorated h-BN. The deviation in structural, electronic, and adsorption properties of h-BN due to Fe decoration has been studied along with the sensing ability to design said material towards carbon monoxide (CO), carbon dioxide (CO2), carbonyl sulfide (COS), carbinol, (CH4O), carbimide (CH2N2), and carbonyl fluoride (CF2O) gases. Gases such as CO, COS, CH2N2, and CF2O exhibited chemisorption, while CO2, and CH4O exhibited physisorption behavior. The introduction of Fe altered the semiconductor properties of h-BN and rendered it metallic. Enhanced electronic properties were observed due to a robust hybridization occurring between the d-orbitals of Fe-decorated BN and the gas molecules. The extended recovery periods observed for gases, aside from CO2, indicate their adhesive interactions with Fe-decorated h-BN. The reduction in desorption duration as temperature rises allows Fe-decorated h-BN to function as a reversible gas sensor. This research opens up a novel pathway for the synthesis and advancement of cost-effective, environmentally friendly double-atom catalysts with high sensitivity for capturing and detecting molecules such as CO, COS, CH2N2, CO2, CH4O, and CF2O.

4.
J Chem Phys ; 159(20)2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38010333

RESUMEN

Semiconductor-based photocatalysts have become increasingly used in the removal of pollutants from wastewater, especially antibiotics. A series of composite-based cuprous oxide and bismuth vanadate (Cu2O/BiVO4) composite-based photocatalysts were synthesized by using the chemical method. The structure of the Cu2O/BiVO4 composite was verified by using x-ray diffraction, scanning electron microscopy, photoluminescence, Fourier transform infrared spectroscopy, and UV-visible spectra. The degradation of methylene blue (MB) and tetracycline (TC) was investigated to check the photocatalytic activity of the Cu2O/BiVO4 composite series. The quantity of Cu2O was varied from 1% to 7% by weight to prepare the series of Cu2O/BiVO4 composites. The analysis of results verified that 5% Cu2O/BiVO4 exhibits an outstanding photocatalytic activity as compared to 1%, 3%, and 7% Cu2O/BiVO4, pure Cu2O, and pure BiVO4 under visible light irradiation. The optimum value of photocatalytic degradation achieved with 5% Cu2O/BiVO4 was 97% for MB dye and 95% for TC in 120 min, which is greater than the photocatalytic degradation of pure BiVO4 (MB 45% and TC 72%), pure Cu2O (MB 57% and TC 80%), 1% Cu2O/BiVO4 (MB 72% and TC 85%), 3% Cu2O/BiVO4 (MB 83% and TC 88%), and 7% Cu2O/BiVO4 (MB 87% and TC 91%). The stability and reusability of Cu2O/BiVO4 were also investigated. To check the major role of trapping in degradation, a trapping experiment was also performed by using three trapping agents: BQ, EDTA, and tBuOH. The results showed that Cu2O/BiVO4 exhibits an improved photocatalytic activity in the degradation of antibiotics in polluted water because the recombination rate of the electron-hole pair decreased and the surface area increased, which increased the active sites for redox reactions. Such a photocatalytic composite with high efficiency has various applications, such as energy production, environmental remediation, and water remediation.

5.
Water Res ; 244: 120473, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37604018

RESUMEN

Quorum quenching (QQ) has effectively prevented biofouling in membrane bioreactors (MBRs) employing isolated QQ bacterial strains. However, the influence of QQ on the microbial population still needs to be fully understood. This research aims to analyze the microbial population in MBRs over an extended period (>250 days) under different conditions, such as varying aeration intensities and doses of QQ bacteria, QQ media, and types of feed. Results show that no significant changes occurred in the structure and diversity of the microbial community in the mixed liquor and biofilm due to QQ treatment. Canonical correspondence analysis did reveal that the microbial communities were strongly influenced by feed types and phases. The microbial community composition varied between bacterial habitats (i.e., mixed liquor and biofilm), showing the two dominant phyla Proteobacteria and Bacteroidota in the former and Proteobacteria and Chloroflexi in the latter. The co-occurrence network analysis indicated that the biofilm (with 163 edges) in the MBR fed with real wastewater exhibited a more intricate network than the biofilm (with 53 edges) in the MBR fed with synthetic wastewater. With QQ, the biofilm exhibited more positive edges than negative ones. The phylogenetic investigation of communities showed that QQ barely affects functional gene-related quorum sensing (e.g., bacterial chemotaxis, motility proteins, and secretion) in mixed liquor but in biofilms at relatively large QQ doses (> 75 mg/L BH4). This research sheds light on the bacterial QQ's role in reducing MBR biofouling and provides crucial insights into its underlying mechanisms.


Asunto(s)
Incrustaciones Biológicas , Microbiota , Percepción de Quorum , Aguas Residuales , Filogenia , Reactores Biológicos/microbiología , Incrustaciones Biológicas/prevención & control , Bacterias , Proteobacteria , Membranas Artificiales
6.
Int J Biometeorol ; 67(9): 1477-1492, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37464201

RESUMEN

Data on historical soil moisture is crucial for assessing and responding to droughts that commonly occur in climate change-affected countries. The Himalayan temperate forests in Pakistan are particularly at risk of climate change. Developing nations lack the means to gather surface soil moisture (SSM) information. Tree rings are one way to bridge this gap. Here, we employed dendrochronological methods on climate-sensitive tree rings from Abies pindrow to reconstruct the SSM in the Western Himalayan mountain region of Pakistan from 1855 to 2020. December (r = 0.41), May (r = 0.40), and June (r = 0.65) SSMs were found to be the limiting factors for A. pindrow growth. However, only the June SSM showed reconstruction possibility (coefficient of efficiency = 0.201 and reduction of error = 0.325). Over the studied period, we found 6 years (wet year) when June SSM was above the threshold of 32.04 (mean + 2 δ) and 1 year (dry year) when June SSM was below the threshold of 21.28 (mean - 2 δ). It was revealed that 1921 and 1917 were the driest and wettest SSM of all time, with means of 19.34 and 36.49, respectively. Our study shows that winter soil moisture is critical for the growing season in the context of climate change. Climate change has broad impacts on tree growth in the Western Himalayas. This study will assist various stakeholders in understanding and managing local and regional climate change.


Asunto(s)
Abies , Suelo , Pakistán , Bosques , Cambio Climático , Sequías
7.
Heliyon ; 9(5): e15978, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37215909

RESUMEN

Bismuth Vanadate (BiVO4) has been synthesized using simple hydrothermal technique while varying the pH of concentrated H2SO4. With the increase of pH values (from 06 to 10), the morphology of the synthesized material tuned in the form of nano-spheres and cubes in the range from 50 to 60 nm. The lateral affect tuned the bandgap of BiVO4 from 2.47 eV to 2.50 eV which is significant in the context of present study. It is worth mentioning that desirous bandgap corresponds to the visible spectrum of the solar light being abundantly available and finds many applications in real life. The synthesized nanomaterial BiVO4 has been characterized through UV-Vis spectroscopy, X-ray diffraction, Scanning electron microscope and energy-dispersive X-ray (EDX) spectroscopy. The synthesized BiVO4 has been tested as photocatalyst for degradation of industrial pollutant from Leather Field Industry. Said catalyst (BiVO4) successfully degraded the industrial pollutant after 3 h under solar light irradiation. Therefore, the BiVO4 can be regarded as potential photocatalyst for degradation of industrial waste which is highly needed.

8.
Saudi J Anaesth ; 17(1): 101-103, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37032661

RESUMEN

Scimitar syndrome is a rare congenital anomaly with a hallmark of an abnormal drainage of pulmonary veins into inferior vena cava instead of the left atrium; this creates a curvilinear radiological pattern resembling a sword (scimitar) on a chest radiograph, thus attracting the name. This case report highlights the challenges during liver transplantation, and perioperative anesthetic management of a patient with an uncorrected Scimitar Syndrome.

9.
Heart Lung ; 60: 127-132, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36996755

RESUMEN

BACKGROUND: Azithromycin has been adopted as a component of the COVID-19 management protocol throughout the global healthcare settings but with a questionable if not downright unsubstantiated evidence base. OBJECTIVES: In order to amalgamate and critically appraise the conflicting evidence around the clinical efficacy of Azithromycin (AZO) vis a vis COVID-19 management outcomes, a meta-analysis of meta-analyses was carried out to establish an evidence-based holistic status of AZO vis a vis its efficacy as a component-in-use of the COVID-19 management protocol. METHODS: A comprehensive systematic search was carried out through PubMed/Medline, Cochrane and Epistemonikos with a subsequent appraisal of abstracts and full-texts, as required. The Quality of Reporting of Meta-analyses (QUOROM) checklist and the Assessment of Multiple Systematic Reviews (AMSTAR) methodology were adopted to assess the methodological quality of the included meta-analyses. Random-effects models were developed to calculate summarized pool Odds Ratios (with 95% confidence interval) for the afore determined primary and secondary outcomes. RESULTS: AZO, when compared with best available therapy (BAT) including or excluding Hydroxychloroquine, exhibited statistically insignificant reduction in mortality [(n= 27,204 patients) OR= 0.77 (95% CI: 0.51-1.16) (I2= 97%)], requirement of mechanical ventilation [(n= 14,908 patients) OR= 1.4 (95% CI: 0.58-3.35) (I2= 98%)], induction of arrhythmia [(n= 9,723 patients) OR= 1.21 (95% CI: 0.63-2.32) (I2= 92%)] and QTc prolongation (a surrogate for torsadogenic effect) [(n= 6,534 patients) OR= 0.62 (95% CI: 0.23-1.73) (I2= 96%)]. CONCLUSION: The meta-analysis of meta-analyses portrays AZO as a pharmacological agent that does not appear to have a comparatively superior clinical efficacy than BAT when it comes to COVID-19 management. Secondary to a very real threat of anti-bacterial resistance, it is suggested that AZO be discontinued and removed from COVID-19 management protocols.


Asunto(s)
COVID-19 , Humanos , Azitromicina/uso terapéutico , SARS-CoV-2 , Tratamiento Farmacológico de COVID-19 , Resultado del Tratamiento
10.
Heliyon ; 9(3): e14144, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36915557

RESUMEN

Sun drying in the open air is quite popular worldwide. However, the use of solar dryers to preserve various perishable agricultural products is a relatively new area of study, and the long-term effects of this method are not yet fully understood. The slow drying process in direct sunlight can contaminate the dried materials by soil and insects. To overcome these challenges, we devised a sun drying system that included a heating part, a drying area, a portable stand, fans, and a 50-W photovoltaic panel. An alternate energy source was used to power the drying process during cloudy days and at night. Fresh Freestone peach, Golden apple, and Anaheim chilies weighing 10 kg each with the initial moisture content of 89%, 87%, and 75% on a wet basis (w.b), respectively, were used in the experiments. The final moisture content of the samples was reduced by an average of 16%, 15%, and 11% for Freestone peaches, Golden apples, and Anaheim chilies, respectively. The quality analysis was carried out to determine sample composition, total bacteria, and color of dried products. The results indicated that the dried products met the recommended quality standards for food products in terms of composition, total bacteria, and color. This research supports the use of a hybrid mixed-mode solar dryer for drying a wide range of perishable agricultural products.

11.
Chemosphere ; 322: 138080, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36781001

RESUMEN

Research on ionic liquids (ILs) and biochars (BCs) is a novel site of scientific interest. An experiment was designed to assess the effect of 1-propanenitrile imidazolium trifluoro methane sulfonate ([C2NIM][CF3SO3]) ionic liquid (IL) and IL-BC combination on the wheat plant. Three working standards of the IL; 50, 250, 500 and 1000 mg/L, prepared in deionized water, were tested in the absence and presence of BC on wheat seedling. Results indicated significant decrease in seed germination (%), length, fresh weight, chlorophyll a, b and carotenoid contents of wheat seedlings at 250, 500 and 1000 mg/L of the IL. An admirable increase in phenolic and 2,2-diphenyl-1-picrylhydrazyl (DPPH) contents of wheat seedlings was noted at 250, 500 and 1000 mg/L of the IL. The application of BC significantly ameliorated the negative effects of IL on the selected parameters of wheat. It is inferred that the undesirable effects of the IL on wheat growth can be positively restored by addition of BC.


Asunto(s)
Líquidos Iónicos , Líquidos Iónicos/química , Clorofila A , Triticum , Plantones
12.
Front Psychol ; 13: 1008890, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36533032

RESUMEN

Global warming and air pollution are severe threats to humans and ecosystems. While some of these issues, particularly those on a small scale requiring low-cost behaviors, may be relieved by developing and implementing environmental policies, it is clear that legislative measures and behaviors requiring a significant degree of sacrifice are required. The goal of this research is to highlight the aspects that can contribute to improve organizational performance in Pakistan's textile industry. Through the moderating function of environmentalism, the study examines the impact of public participation, government regulation, and organizational environmental management systems (EMSs) on environmental and organizational performance The findings show that public participation, government regulation, and the organizational EMS all have a significant impact on both environmental and organizational success. Data were collected via a survey questionnaire. Smart-PLS-3 was used to evaluate the data. Furthermore, if environmentalism is regarded as a moderator, the overall influence on organizational performance will be greater. Public participation, government regulations, and an organization's EMS are all seen to have a substantial influence on both environmental and organizational success.

13.
Nanotechnology ; 34(1)2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36195011

RESUMEN

Heterostructure BiVO4/Bi2O3nanocomposites with enhanced visible light activity are effectively synthesized through an easiest and single step hydrothermal route, using bismuth subnitrate and ammonium meta-vanadate as main raw materials in existence of citric acid. The phase and surface structure, topography and optical properties of synthesized composites are characterized by XRD, SEM, EDX, FTIR, UV-Visible and PL spectroscopy. It was found that 5%BiVO4/Bi2O3(BOBV-5) nanocomposite exhibit excellent photocatalytic performance for rhodamine B dye degradation and tetracyclic under irradiation of visible light as compared to single component i.e. BiVO4. The increased photocatalytic activity should be ascribed for making p-n heterojunction among p-type Bi2O3and n-type BiVO4. This p-n heterojunction successfully reduce the recombination of photogenerated charge carriers. Furthermore, the BOBV-5 novel photocatalyst shows good stability in constructive five cycles and photocatalytic activity is best for conquering photo corrosion of a photocatalysts. To explain charge migration route, whole photocatalytic mechanism was described in terms of energy band structures. Furthermore, the present work is helpful effort for design of new visible light photocatalytic materials with heterojunction structures.

14.
Front Psychol ; 13: 884198, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35936318

RESUMEN

In today's complex selling environment, it is challenging for sales leaders to enhance the effectiveness of their sales teams. The aim of this study is to observe the impact of authentic leadership on salespersons' internal and external behaviors under B2B selling context [i.e., transactive memory system (TMS), innovative work behavior, and customer-directed OCB] and their consequences in team selling performance. Respondents of our survey included salespersons and managers working in the sales departments of pharmaceutical companies. By using structural equation modeling, the dyad responses from 348 matched salespeople-managers were analyzed. The findings disclose that authentic leadership behavior has a stronger relationship with the TMS, innovative work behavior, and customer-directed OCB. Our results also indicate that innovative work behavior and customer-directed OCB are potentially mediated between authentic leadership and team selling performance relationship. The theoretical implication of these results for managerial practice is also discussed.

15.
Front Psychol ; 13: 883224, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35874334

RESUMEN

The primary purpose of the research is to investigate the mediating role of corporate sustainability in the relationship between the impacts of transformational leadership on the performance of firms. This study also aimed to investigate the moderating role of knowledge-sharing on the relationship of transformational leadership with corporate sustainability. Respondents of the study were the top management of large Chinese automobile sectors, such as Shanghai Automotive Business Corporation (Group), China FAW Group Corporation, Dongfeng Motor Co., Ltd., Beijing Automotive Group Co., Ltd., and China North Industries Group Corporation. These are the companies with the biggest market share in the automobile manufacturing industry in China. The data was gathered by using a self-administrative survey questionnaire from 198 individuals operating in different automobile industries in different sectors of China. The data were analyzed using structural equation modeling (SEM) through the Smart PLS 3.3.2 software. The results of this study revealed that transformational leadership has a positive and significant effect on the performance of the firm. Corporate sustainability has a significant positive mediating role in the association of transformational leadership and firm performance. Findings indicated that knowledge-sharing also has a positive moderating role in the association between transformational leadership and firm performance. The findings of this study contribute to the body of knowledge and show that leadership style has a significant effect on firm performance and that knowledge-sharing culture in firms is essential for better performance of the firm. Furthermore, firms may improve their performance by improving their sustainability and by creating knowledge-sharing culture. The findings are important, particularly in connection with a developed country like China. The findings have important insights for various stakeholders, i.e., government, regulatory bodies, practitioners, academia, industry, and researchers.

16.
J Ayub Med Coll Abbottabad ; 34(2): 381-384, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35576309

RESUMEN

Echinococcosis is a disease that has been affecting human beings since decades and is primarily a zoonotic disease. The larvae of genus Echinococcus causes this disease. The most common sites for these cysts are the lungs and liver. Cardiac hydatidosis is a rare phenomenon and the incidence of such cases is about 1.3%. The case presented is of a 15- year-old boy who would have shortness of breath on exertion and acute right leg pain. To diagnose cardiac variant of the cystic disease, computed topography (CT) and echocardiography were done. Doppler studies confirmed acute limb ischemia. The treatment modality was an open-heart surgery and bilateral embolectomy of the popliteal artery. The patient was discharged to home with albendazole chemotherapy. The study gives an insight into an unusual presentation and successful treatment of cardiac hydatid cyst as well as the associated complications that can be encountered.


Asunto(s)
Equinococosis , Echinococcus , Adolescente , Albendazol/uso terapéutico , Animales , Equinococosis/complicaciones , Equinococosis/diagnóstico , Equinococosis/cirugía , Ecocardiografía , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/cirugía , Humanos , Masculino
17.
Plants (Basel) ; 11(3)2022 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-35161352

RESUMEN

Quinoa is a climate resilience potential crop for food security due to high nutritive value. However, crop variable response to nitrogen (N) use efficiency may lead to affect grain quality and yield. This study compared the performance of contrasting quinoa genotypes (UAF Q-7, EMS-line and JQH1) to fertilizer urea enriched with urease and nitrification inhibitors (NIs; 1% (w/w) thiourea + boric acid + sodium thiosulphate), ordinary urea and with no N as control. Application of NIs-enriched urea improved plant growth, N uptake and chlorophyll values in quinoa genotype UAF-Q7 and JHQ1, however, highest nitrate reductase (NR) activity was observed in EMS-line. Quinoa plants supplied with NIs-enriched urea also completed true and multiple leaf stage, bud formation, flowering, and maturity stages earlier than ordinary urea and control, nevertheless, all quinoa genotypes reached true and multiple leaf stage, flowering and maturity stages at same time. Among photosynthetic efficiency traits, application of NIs-enriched urea expressed highest photosynthetic active radiations (PAR), electron transport rate (ETR), current fluorescence (Ft) and reduced quantum yield (Y) in EMS line. Nitrogen treatments had no significant difference for panicle length, however, among genotypes, UAF-Q7 showed highest length of panicle followed by others. Among yield attributes, NIs-enriched urea expressed maximum 1000-seed weight and seed yield per plant in JQH-1 hybrid and EMS-line. Likely, an increase in quinoa grain protein contents was observed in JQH-1 hybrid for NIs-enriched urea. In conclusion, NIs-enriched urea with urease and nitrification inhibitors simultaneously can be used to improve the N uptake, seed yield and grain protein contents in quinoa, however, better crop response was attributed to enhanced plant growth and photosynthetic efficiency.

18.
Biol Trace Elem Res ; 200(11): 4855-4864, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34994949

RESUMEN

Green synthesis of nanoparticles using plant-based extracts is momentously used in different fields of science because of their environment-friendly nature and cost-effectiveness. In the present study, silver nanoparticles were synthesized by using rice husk (non-toxic agricultural by-product) to determine their efficacy against aphid's (Sitobion avanae) mortality and antioxidant enzymes. UV-VIS spectroscopy of synthesized nanoparticles showed the maximum absorption peak at 440 nm, FTIR exhibited different peaks, and SEM confirmed the roughly spherical shape and 70-80 nm size of silver nanoparticles. Aphids were reared on wheat seedlings in the laboratory at 20-25 °C and 16:8 (light:dark) photoperiod. Insecticidal bioassays were conducted on aphids at three different concentrations (200 ppm, 400 ppm, 600 ppm) of nanoparticles for 2 days. Results showed the highest mortality of aphids being 93.3% at 600 ppm nanoparticle concentration after 2 days while the lowest mortality was observed at 200 ppm. Furthermore, the effect of silver nanoparticles on antioxidant enzymes was studied. Results of enzyme assays revealed that enzyme activities of catalase and glutathione-s-transferase increased in response to increased nanoparticle concentration. The current findings suggested that silver nanoparticles have probation for replacing commercially available insecticides for combating pests.


Asunto(s)
Áfidos , Insecticidas , Nanopartículas del Metal , Nanopartículas , Oryza , Animales , Antioxidantes/análisis , Antioxidantes/farmacología , Catalasa , Glutatión/análisis , Insecticidas/química , Insecticidas/farmacología , Larva , Nanopartículas del Metal/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Plata/química , Plata/farmacología , Transferasas/análisis , Transferasas/farmacología
19.
ACS Omega ; 5(38): 24403-24411, 2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-33015456

RESUMEN

The chemical looping gasification (CLG) process is a promising pathway to produce hydrogen-enriched syngas with biomass. It is urgent to enhance the reactivity and thermal stability of oxygen carriers (OC) and capture the inherently separated CO2. This work presents the strategy of simultaneous modification of a Fe2O3/Al2O3 oxygen carrier and the supplement of an oxidant for corn stalk chemical looping gasification by introducing KNO3-containing ethanol liquid waste. CaO is employed to capture the generated CO2 and promote the reaction balance toward hydrogen production in a fuel reactor (FR). The highest carbon conversion reaction rate of 1.1 × 10-4 mol/g could be obtained at the ratio of CaO to fuel carbon and the reaction temperature of 1.5 and 600 °C, respectively. The kinetics and thermodynamics analyses under the optimized condition are further discussed to verify the possibility and high efficiency of using alkaline organic liquid waste to boost solid fuel gasification for hydrogen production. This CLG strategy shows multifunctional merits, including organic liquid waste treatment, biomass CLG promotion, and hydrogen production enhancement.

20.
Cureus ; 12(5): e8154, 2020 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-32550072

RESUMEN

Brucellosis is a form of zoonotic infection caused by various Brucella organisms. It most commonly presents as a case of pyrexia of unknown origin, alongside symptoms such as night sweats, malaise, arthralgias, and myalgias. This report describes the case of a man who presented with pyrexia of unknown origin for one month; he was diagnosed to be a case of brucellosis after enteric fever was ruled out. Investigations were ordered as it was a differential diagnosis with high clinical suspicion due to the presenting complaint and potential exposure of tainted consumable products. The systemic disease was determined to be brucellosis following blood results demonstrating positive antibody titers, and the suspicion of exposure due to widespread inadequacies in sterilization of food products.

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