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1.
Nat Immunol ; 24(9): 1473-1486, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37580603

RESUMO

Omnivorous animals, including mice and humans, tend to prefer energy-dense nutrients rich in fat over plant-based diets, especially for short periods of time, but the health consequences of this short-term consumption of energy-dense nutrients are unclear. Here, we show that short-term reiterative switching to 'feast diets', mimicking our social eating behavior, breaches the potential buffering effect of the intestinal microbiota and reorganizes the immunological architecture of mucosa-associated lymphoid tissues. The first dietary switch was sufficient to induce transient mucosal immune depression and suppress systemic immunity, leading to higher susceptibility to Salmonella enterica serovar Typhimurium and Listeria monocytogenes infections. The ability to respond to antigenic challenges with a model antigen was also impaired. These observations could be explained by a reduction of CD4+ T cell metabolic fitness and cytokine production due to impaired mTOR activity in response to reduced microbial provision of fiber metabolites. Reintroducing dietary fiber rewired T cell metabolism and restored mucosal and systemic CD4+ T cell functions and immunity. Finally, dietary intervention with human volunteers confirmed the effect of short-term dietary switches on human CD4+ T cell functionality. Therefore, short-term nutritional changes cause a transient depression of mucosal and systemic immunity, creating a window of opportunity for pathogenic infection.


Assuntos
Mucosa , Salmonella typhimurium , Humanos , Camundongos , Animais , Linfócitos T , Imunidade nas Mucosas
2.
Nanotechnology ; 35(20)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38320322

RESUMO

The increasing use of nanomaterials in consumer products is expected to lead to environmental contamination sometime soon. As water pollution is a pressing issue that threatens human survival and impedes the promotion of human health, the search for adsorbents for removing newly identified contaminants from water has become a topic of intensive research. The challenges in the recyclability of contaminated water continue to campaign the development of highly reusable catalysts. Although exfoliated 2D MXene sheets have demonstrated the capability towards water purification, a significant challenge for removing some toxic organic molecules remains a challenge due to a need for metal-based catalytic properties owing to their rapid response. In the present study, we demonstrate the formation of hybrid structure AuNPs@MXene (Mo2CTx) during the sensitive detection of Au nanoparticle through MXene sheets without any surface modification, and subsequently its applications as an efficient catalyst for the degradation of 4-nitrophenol (4-NP), methyl orange (MO), and methylene blue (MB). The hybrid structure (AuNPs@MXene) reveals remarkable reusability for up to eight consecutive cycles, with minimal reduction in catalytic efficiency and comparable apparent reaction rate constant (Kapp) values for 4-NP, MB, and MO, compared to other catalysts reported in the literature.

3.
J Fluoresc ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042358

RESUMO

An Indane-1-one derivative 11-(1-benzyl-1H-indol-3-yl)-10,12-dihydrodiindeno[1,2-b:2',1'-e]-pyridine (BDP) has been synthesized by the reaction of Indan-1-one with 1-benzyl-1H-indole-3-carbaldehyde. FT-IR, 1H-NMR, 13N-NMR and Mass spectroscopic techniques has been used to confirmed the structure of BDP. The observed photophysical changes in BDP across various solvents were associated. The impact of various interactions on photophysical parameters, including Stokes shift, dipole moment, oscillator strength, and fluorescence quantum yields, has been assessed in relation to solvent polarity. Moreover, BDP demonstrates potential as a selective fluorescent chemosensor for detecting Fe3+ ion within a range of cations in an aqueous DMSO environment. A thorough investigation into the recognition mechanism of BDP towards Fe3+ ion has been conducted using Benesi-Hildebrand and Stern-Volmer, measurements. BDP forms a 2:1 complex with the Fe3+ ion, exhibiting fluorescent quenching behaviour.

4.
Health Res Policy Syst ; 22(1): 125, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39252001

RESUMO

BACKGROUND: The healthcare system in India is tiered and has primary, secondary and tertiary levels of facilities depending on the complexity and severity of health challenges at these facilities. Evidence suggests that emergency services in the country is fragmented. This study aims to identify the barriers and facilitators of emergency care delivery for patients with time-sensitive conditions, and develop and implement a contextually relevant model, and measure its impact using implementation research outcomes. METHODS: We will study 85 healthcare facilities across five zones of the country and focus on emergency care delivery for 11 time-sensitive conditions. This implementation research will include seven phases: the preparatory phase, formative assessment, co-design of Model "Zero", co-implementation, model optimization, end-line evaluation and consolidation phase. The "preparatory phase" will involve stakeholder meetings, approval from health authorities and the establishment of a research ecosystem. The "formative assessment" will include quantitative and qualitative evaluations of the existing healthcare facilities and personnel to identify gaps, barriers and facilitators of emergency care services for time-sensitive conditions. On the basis of the results of the formative assessment, context-specific implementation strategies will be developed through meetings with stakeholders, providers and experts. The "co-design of Model 'Zero'" phase will help develop the initial Model "Zero", which will be pilot tested on a small scale (co-implementation). In the "model optimization" phase, iterative feedback loops of meetings and testing various strategies will help develop and implement the final context-specific model. End-line evaluation will assess implementation research outcomes such as acceptability, adoption, fidelity and penetration. The consolidation phase will include planning for the sustenance of the interventions. DISCUSSION: In a country such as India, where resources are scarce, this study will identify the barriers and facilitators to delivering emergency care services for time-sensitive conditions across five varied zones of the country. Stakeholder and provider participation in developing consensus-based implementation strategies, along with iterative cycles of meetings and testing, will help adapt these strategies to local needs. This approach will ensure that the developed models are practical, feasible and tailored to the specific challenges and requirements of each region.


Assuntos
Serviços Médicos de Emergência , Índia , Humanos , Serviços Médicos de Emergência/organização & administração , Instalações de Saúde/normas , Emergências , Prestação Integrada de Cuidados de Saúde/organização & administração , Projetos de Pesquisa , Atenção à Saúde , Fatores de Tempo , Pesquisa sobre Serviços de Saúde , Ciência da Implementação , Participação dos Interessados
5.
Inflammopharmacology ; 32(2): 1387-1400, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38430414

RESUMO

Atherosclerosis, a multifaceted and persistent inflammatory condition, significantly contributes to the progression of cardiocerebrovascular disorders, such as myocardial infarctions and cerebrovascular accidents. It involves the accumulation of cholesterol, fatty deposits, calcium and cellular debris in the walls of arteries, leading to the formation of plaques. Our aim is to investigate the potential of sinomenine to counteract atherosclerosis in mice lacking Apolipoprotein E (ApoE-/-) Mice. We employed the high-fat diet-induced method to induce atherosclerosis in ApoE-/- mice, and the mice were treated with sinomenine (5, 10, and 15 mg/kg) and simvastatin (0.5 mg/kg) for 12 weeks. Body weight, water intake, and food intake were assessed. Lipid parameters, oxidative stress, inflammatory cytokines, and mRNA levels were estimated. Sinomenine treatment remarkably (P < 0.001) suppressed body weight, along with food and water intake. Sinomenine altered the levels of total cholesterol (TC), high-density lipoprotein (HDL), triglyceride (TG), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL), which were modulated in the atherosclerosis group. Sinomenine treatment also altered the levels of oxidative stress parameters such as glutathione peroxidase (GPx), catalase (CAT), malonaldehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH). In addition, it modulated cardiac parameters like C-reactive protein (CRP), endothelin-1 (ET-1), thromboxane B2 (TXB2), nitric oxide (NO), cardiac troponin I (cTnI), lactate dehydrogenase (LDH), and creatinine kinase isoenzymes (CK-MB). Inflammatory cytokines interleukin (IL)-1α, IL-1ß, TNF-α, IL-6, and IL-10 were also affected. Sinomenine further suppressed the mRNA expression of IL-6, IL-17, IL-10, tumor necrosis factor-α (TNF-α), Il-1ß, monocyte chemoattractant protein-1 (MCP-1), MCP-2, MCP-3, transforming Growth Factor-1ß (TGF-1ß), vascular cell adhesion molecule 1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1). The results suggest that sinomenine remarkably suppressed the development of atherosclerosis in the early stage.


Assuntos
Aterosclerose , Interleucina-10 , Morfinanos , Animais , Camundongos , Apolipoproteínas , Apolipoproteínas E , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Peso Corporal , Colesterol , Citocinas , Interleucina-6 , Lipoproteínas LDL , Camundongos Knockout , Camundongos Knockout para ApoE , RNA Mensageiro , Fator de Necrose Tumoral alfa/metabolismo
6.
Environ Monit Assess ; 196(4): 342, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438750

RESUMO

Air pollution is growing at alarming rates on regional and global levels, with significant consequences for human health, ecosystems, and change in climatic conditions. The present 12 weeks (4 October 2021, to 26 December 2021) study revealed the different ambient air quality parameters, i.e., PM2.5, PM10, SO2, NO2, and O3 over four different sampling stations of Delhi-NCR region (Dwarka, Knowledge park III, Sector 125, and Vivek Vihar), India, by using satellite remote sensing data (MERRA-2, OMI, and Aura Satellite) and different ground-based instruments. The ground-based observation revealed the mean concentration of PM2.5 in Dwarka, Knowledge park III, Sector 125, and Vivek Vihar as 279 µg m-3, 274 µg m-3, 294 µg m-3, and 365 µg m-3, respectively. The ground-based instrumental concentration of PM2.5 was greater than that of satellite observations, while as for SO2 and NO2, the mean concentration of satellite-based monitoring was higher as compared to other contaminants. Negative and positive correlations were observed among particulate matter, trace gases, and various meteorological parameters. The wind direction proved to be one of the prominent parameter to alter the variation of these pollutants. The current study provides a perception into an observable behavior of particulate matter, trace gases, their variation with meteorological parameters, their health hazards, and the gap between the measurements of satellite remote sensing and ground-based measurements.


Assuntos
Poluentes Atmosféricos , Humanos , Dióxido de Nitrogênio , Ecossistema , Monitoramento Ambiental , Material Particulado , Gases
7.
Indian J Crit Care Med ; 28(2): 175-176, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38323258

RESUMO

How to cite this article: Dash S, Pandalanghat S, Kumar Y. An Unusual Case of Hoarseness of Voice and Dysphagia in Multiple Myeloma with Amyloidosis. Indian J Crit Care Med 2024;28(2):175-176.

8.
Phys Chem Chem Phys ; 25(17): 12363-12370, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37092248

RESUMO

Nonfullerene polyaromatic molecules such as perinone are emerging as alternatives to fullerene derivatives due to their low manufacturing cost, ease of functionalization, and processing to improve the efficiency of optoelectronic devices. In this paper, we have used ultrafast transient absorption (TA) spectroscopy to probe the excited state dynamics in cis and trans perinone molecules. We have performed TA measurements in solution as well as thin films to provide a comprehensive understanding of excited-state processes occurring in cis and trans perinone molecules. Our results reveal the triplet state formation in perinone thin films through intersystem crossing and provide an in-depth understanding of the relaxation pathways of perinone molecules, which will be beneficial for designing and optimizing the device efficiencies of perinone based photovoltaic devices.

9.
Can J Neurol Sci ; 50(4): 579-583, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-35684949

RESUMO

BACKGROUND: Sensory-motor decoupling at the cortical level involving cholinergic circuitry has also been reported in Parkinson's Disease (PD). Short-latency afferent inhibition (SAI) is a transcranial magnetic stimulation (TMS) paradigm that has been used previously to probe cortical cholinergic circuits in well-characterised subgroups of patients with PD. In the current study, we compared SAI in a cohort of PD patients at various stages of disease and explored correlations between SAI and various clinical measures of disease severity. METHODS: The modified Hoehn and Yahr (H&Y) scale was used to stage disease in 22 patients with PD. Motor and cognitive function were assessed using the MDS-UPDRS (Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale) part III and MoCA (Montreal Cognitive Assessment) score, respectively. Objective gait assessment was performed using an electronic walkway (GAITRite®). SAI was measured as the average percentage inhibition of test motor-evoked potentials (MEPs) conditioned by electrical stimulation of the contralateral median nerve at the wrist. RESULTS: SAI was significantly reduced in patients with advanced PD (H&Y stage 3) compared to early PD patients (H&Y stage 1) on pairwise comparison. The visuospatial executive function and orientation domains of cognition demonstrated significant negative associations with SAI. CONCLUSION: Cortical sensory-motor integration is progressively diminished as disease progresses. The observation that a reduction in SAI is associated with a reduction in cognitive function possibly reflects the progressive involvement of cortical cholinergic circuits in PD with increasing motor stage. Future longitudinal studies are necessary to confirm this preliminary result.


Assuntos
Inibição Neural , Doença de Parkinson , Humanos , Inibição Neural/fisiologia , Potencial Evocado Motor/fisiologia , Punho , Colinérgicos
10.
Lipids Health Dis ; 22(1): 1, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609276

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD), especially nonalcoholic steatohepatitis (NASH) increases the risk for liver cirrhosis. Noninvasive tests for NAFLD/NASH exist, but they are unreliable and thus liver biopsy remains the standard for diagnosis and new noninvasive diagnostic approaches are of great interest. The aim of this study was to test whether the serum levels of fatty acid-binding protein-4 (FABP4) and matrix metalloproteinase-9 (MMP9) could be used as a diagnostic tool for NASH. METHODS: Patients who underwent bariatric surgery and simultaneous liver biopsy were identified. Biopsies were assigned a NAFLD activity score (NAS). MMP9- and FABP4- Enzyme-linked Immunosorbent Assays (ELISAs) on serum samples were performed. The serum levels of FABP4/MMP9 were compared and different models to predict NASH were developed. RESULTS: A total of 84 patients were included, 28 patients (33.3%) were diagnosed with NASH. Higher concentrations of MMP9 in NASH patients (p < 0.01) were detected. FABP4 concentrations were not significantly increased. A moderate correlation between the NAS and MMP9 concentrations (r = 0.32, P < 0.01) was observed. The neural network model fit best with the dataset, with an area under the curve (AUC) of 83% and an accuracy of 88%. CONCLUSION: Serum MMP9 levels are increased in patients with NASH and should routinely be measured in patients with obesity, but further investigations are needed to improve noninvasive NASH diagnosis.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Metaloproteinase 9 da Matriz , Cirrose Hepática/patologia , Obesidade/patologia , Proteínas de Ligação a Ácido Graxo , Biópsia , Fígado/patologia , Biomarcadores
11.
Pediatr Dermatol ; 40(6): 1101-1103, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37029098

RESUMO

Acute generalized exanthematous pustulosis (AGEP) is a rare severe cutaneous adverse reaction triggered in most cases by drugs. It is characterized by abrupt onset and rapid evolution of fields of sterile pustules on an erythematous background. The role of genetic predisposition in this reactive disorder is being explored. We report the simultaneous occurrence of AGEP in two siblings after being exposed to the same drug.


Assuntos
Pustulose Exantematosa Aguda Generalizada , Humanos , Pustulose Exantematosa Aguda Generalizada/diagnóstico , Pustulose Exantematosa Aguda Generalizada/etiologia , Irmãos , Pele , Administração Cutânea
12.
Cereal Res Commun ; : 1-23, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37361480

RESUMO

Rice (Oryza sativa L.)-wheat (Triticum aestivum L.) cropping system in north-western Indo-Gangetic Plains performed a crucial role in the national food security. However, the widespread and intensive cultivation of this system has led to serious problems such as declining groundwater table (~1 meter year-1) with sharp increase in number of districts under over-exploitation category, residue burning, higher greenhouse gases emission and herbicide resistance in weeds, causing stagnant crop productivity and lesser profitability. In this review article, an attempt has been made to discuss the major issues pertaining to intensive rice-wheat cultivation amidst climate vagaries and futuristic approach to address these challenges. Different tillage- and crop-specific recommendations such as adoption of direct seeded rice, diversification with lesser resource guzzling crops such as maize (Zea mays L.) at least on the periodic manner especially in light-medium soils, inclusion of summer legumes and alternative tillage systems (permanent beds and zero tillage with residue retention) have been suggested to address these issues. However, crop performance under these techniques has been found to be location, soil and cultivar specific. The absence of aerobic tailored genotypes and weeds have been identified as the major constraints in adoption of direct seeded rice. The integrated strategies of conservation tillage, crop breeding program and resource conserving region- and soil-specific agronomic measures with crop diversification would be helpful in tackling the sustainability issues. It requires future efforts on developing crop genotypes suited to conservation tillage, effective weed control strategies and trainings and demonstrations to farmers to switch from conventional rice-wheat system to alternative cropping systems.

13.
Homeopathy ; 112(1): 12-21, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35948020

RESUMO

BACKGROUND: The clinical profile and course of COVID-19 evolved perilously in a second wave, leading to the use of various treatment modalities that included homeopathy. This prognostic factor research (PFR) study aimed to identify clinically useful homeopathic medicines in this second wave. METHODS: This was a retrospective, multi-centred observational study performed from March 2021 to May 2021 on confirmed COVID-19 cases who were either in home isolation or at COVID Care Centres in Delhi, India. The data were collected from integrated COVID Care Centres where homeopathic medicines were prescribed along with conventional treatment. Only those cases that met a set of selection criteria were considered for analysis. The likelihood ratio (LR) was calculated for the frequently occurring symptoms of the prescribed medicines. An LR of 1.3 or greater was considered meaningful. RESULTS: Out of 769 confirmed COVID-19 cases reported, 514 cases were selected for analysis, including 467 in home isolation. The most common complaints were cough, fever, myalgia, sore throat, loss of taste and/or smell, and anxiety. Most cases improved and there was no adverse reaction. Certain new symptoms, e.g., headache, dryness of mouth and conjunctivitis, were also seen. Thirty-nine medicines were prescribed, the most frequent being Bryonia alba followed by Arsenicum album, Pulsatilla nigricans, Belladonna, Gelsemium sempervirens, Hepar sulphuris, Phosphorus, Rhus toxicodendron and Mercurius solubilis. By calculating LR, the prescribing indications of these nine medicines were ascertained. CONCLUSION: Add-on use of homeopathic medicines has shown encouraging results in the second wave of COVID-19 in integrated care facilities. Further COVID-related research is required to be undertaken on the most commonly prescribed medicines.


Assuntos
COVID-19 , Homeopatia , Materia Medica , Humanos , Prognóstico , Estudos Retrospectivos , Materia Medica/uso terapêutico
14.
Bull Environ Contam Toxicol ; 110(4): 80, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37046120

RESUMO

The current study aimed to assess how high concentrations of ozone (O3) and suspended particulate matter (SPM) alter biochemical properties of high yielding wheat cultivars (i.e., HD3086 and HD2967) grown under 10 km radius in 8 villages, located around Thermal Power Plant (TPP), Auraiya, Uttar Pradesh, India. Significant foliar damage was brought on by O3 and SPM exposure in both wheat cultivars and noted for consecutive 2 years as per emission patterns, air movement and biochemical defense capabilities. The detected air pollutants at the chosen experimental site ranged from 34 to 46 ppb O3 and 139-189 µg/m3 SPM. Range of biochemical parameter for both cultivars are as pH 6.6-7.1, relative water content (RWC) 44-62%, chlorophyll 0.23-0.35 mg/g, ascorbic acid (AA) 54-68 mg/g and air pollution tolerance index (APTI) 47-72. It has been observed that SPM deposition had a meaningful impact (P-value = 0.05) on the chlorophyll, pH, RWC and APTI.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Triticum/fisiologia , Monitoramento Ambiental , Folhas de Planta/química , Poluição do Ar/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Clorofila/análise , Ozônio/toxicidade , Ozônio/análise , Material Particulado/análise , Centrais Elétricas
15.
J Food Sci Technol ; 60(12): 2990-3001, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37786602

RESUMO

Kodo (Paspalum scrobiculatum) and little (Panicum sumatrense) millet grains were utilized to minimize their antinutrient content (phytate and tannin) and maximize their antioxidant activity (DPPH) by studying the effect of ultrasonication time, germination time and temperature using central composite rotatable design. Results revealed the optimum conditions for producing ultrasonicated and germinated kodo and little millet flour of the highest antioxidant activity and lowest antinutrient content (phytate and tannin) by using 30 min for ultrasonication, 72 h for germination at 40 °C. Further, a second order model was developed to describe and predict the effect of process variables on antioxidant activity and antinutrient contents. Extended experiments were carried out under the optimized conditions to validate the developed model. The antioxidant activity obtained was 88.46% RSA and 89.06% RSA for kodo and little millet grain flours, respectively whereas antinutrient content for phytate was 0.165 mol/kg and 0.199 mol/kg and for tannin 2.88 mol/kg and 9.51 mol/kg, for kodo and little millet grain flours, respectively. This study provides useful information about the potential utilization of ultrasonicated and germinated kodo and little millet grain flours for the development of functional foods.

16.
J Food Sci Technol ; 60(3): 879-888, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36908345

RESUMO

The present study focused on the effect of different drying temperatures (40, 50, 60 and 70 °C) and combination of pre-treatments: potassium metabisulphite (KMS), potassium metabisulphite + Citric acid + blanching (KCB)] on functional, thermo-pasting and antioxidant properties of elephant foot yam (EFY) powder. Drying temperature and pretreatment reduces the water and oil absorption capacity, and the highest values were 2.34 g/g and 1.19 g/g for drying at 40 °C for the untreated sample, respectively. KMS pretreatment enhanced the bulk density, foaming capacity, emulsion capacity, and emulsion stability with an increase in drying temperature. Pasting temperature and viscosity decreased with an increase in drying temperature, and the maximum was observed at 40 °C for KMS pretreatment. Blanching increases the gelatinization temperature resulting in higher mid-and end-temperatures for KCB pretreatment. The antioxidant properties decreased with an increase in the drying temperature and were found to be minimal in the case of KCB treated samples.

17.
Inorg Chem ; 61(12): 4995-5009, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35293211

RESUMO

In the present era, electrochemical water splitting has been showcased as a reliable solution for alternative and sustainable energy development. The development of a cheap, albeit active, catalyst to split water at a substantial overpotential with long durability is a perdurable challenge. Moreover, understanding the nature of surface-active species under electrochemical conditions remains fundamentally important. A facile hydrothermal approach is herein adapted to prepare covellite (hexagonal) phase CuS nanoplates. In the covellite CuS lattice, copper is present in a mixed-valent state, supported by two different binding energy values (932.10 eV for CuI and 933.65 eV for CuII) found in X-ray photoelectron spectroscopy analysis, and adopted two different geometries, that is, trigonal planar preferably for CuI and tetrahedral preferably for CuII. The as-synthesized covellite CuS behaves as an efficient electro(pre)catalyst for alkaline water oxidation while deposited on a glassy carbon and nickel foam (NF) electrodes. Under cyclic voltammetry cycles, covellite CuS electrochemically and irreversibly oxidized to CuO, indicated by a redox feature at 1.2 V (vs the reversible hydrogen electrode) and an ex situ Raman study. Electrochemically activated covellite CuS to the CuO phase (termed as CuSEA) behaves as a pure copper-based catalyst showing an overpotential (η) of only 349 (±5) mV at a current density of 20 mA cm-2, and the TOF value obtained at η349 (at 349 mV) is 1.1 × 10-3 s-1. A low Rct of 5.90 Ω and a moderate Tafel slope of 82 mV dec-1 confirm the fair activity of the CuSEA catalyst compared to the CuS precatalyst, reference CuO, and other reported copper catalysts. Notably, the CuSEA/NF anode can deliver a constant current of ca. 15 mA cm-2 over a period of 10 h and even a high current density of 100 mA cm-2 for 1 h. Post-oxygen evolution reaction (OER)-chronoamperometric characterization of the anode via several spectroscopic and microscopic tools firmly establishes the formation of crystalline CuO as the active material along with some amorphous Cu(OH)2 via bulk reconstruction of the covellite CuS under electrochemical conditions. Given the promising OER activity, the CuSEA/NF anode can be fabricated as a water electrolyzer, Pt(-)//(+)CuSEA/NF, that delivers a j of 10 mA cm-2 at a cell potential of 1.58 V. The same electrolyzer can further be used for electrochemical transformation of organic feedstocks like ethanol, furfural, and 5-hydroxymethylfurfural to their respective acids. The present study showcases that a highly active CuO/Cu(OH)2 heterostructure can be constructed in situ on NF from the covellite CuS nanoplate, which is not only a superior pure copper-based electrocatalyst active for OER and overall water splitting but also for the electro-oxidation of industrial feedstocks.

18.
Phys Chem Chem Phys ; 24(11): 6580-6589, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35234230

RESUMO

Rare-earth (RE)/transition metal (TM) ferromagnetic heterostructures with competing interfacial coupling and Zeeman energy provide a rich ground to study different phase states as a function of magnetic field and temperature. The interface morphology as a knob in these RE/TM heterostructures provides an excellent opportunity to engineer the macroscopic magnetic response by tuning the interface dependent microscopic interactions between the layers. We have investigated the interface morphology driven structure and magnetic properties of a Gd/Co multilayer. The interface morphology of the multilayer was controlled by annealing the multilayer at a relatively low temperature of 573 K under vacuum conditions. Combining the different experimental techniques and a simple one-dimensional spin-based model calculation, we studied the detailed magnetic structure and magnetization reversal mechanism in this system across compensation temperature (Tcomp), which suggested a strong interface dependent coupling in the system. We showed that changes in the interface morphology of the Gd/Co multilayer strongly influence the macroscopic magnetic properties of the system. The calculation also confirms the formation of a helical magnetic structure with a 2π domain wall in this system below Tcomp. The experimental finding and the simulation of this technologically important system will help to understand the physics of all-optical switching and related applications.

19.
J Biol Chem ; 295(47): 15797-15809, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-32994224

RESUMO

Regulatory elements (REs) consist of enhancers and promoters that occupy a significant portion of the noncoding genome and control gene expression programs either in cis or in trans Putative REs have been identified largely based on their regulatory features (co-occupancy of ESC-specific transcription factors, enhancer histone marks, and DNase hypersensitivity) in mouse embryonic stem cells (mESCs). However, less has been established regarding their regulatory functions in their native context. We deployed cis- and trans-regulatory elements scanning through saturating mutagenesis and sequencing (ctSCAN-SMS) to target elements within the ∼12-kb cis-region (cis-REs; CREs) of the Oct4 gene locus, as well as genome-wide 2,613 high-confidence trans-REs (TREs), in mESCs. ctSCAN-SMS identified 10 CREs and 12 TREs as novel candidate REs of the Oct4 gene in mESCs. Furthermore, deletions of these candidate REs confirmed that the majority of the REs are functionally active, and CREs are more active than TREs in controlling Oct4 gene expression. A subset of active CREs and TREs physically interact with the Oct4 promoter to varying degrees; specifically, a greater number of active CREs, compared with active TREs, physically interact with the Oct4 promoter. Moreover, comparative genomics analysis reveals that a greater number of active CREs than active TREs are evolutionarily conserved between mice and primates, including humans. Taken together, our study demonstrates the reliability and robustness of ctSCAN-SMS screening to identify critical REs and investigate their roles in the regulation of transcriptional output of a target gene (in this case Oct4) in their native context.


Assuntos
Loci Gênicos , Células-Tronco Embrionárias Murinas/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Elementos Reguladores de Transcrição , Animais , Sistemas CRISPR-Cas , Linhagem Celular , Estudo de Associação Genômica Ampla , Humanos , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Fator 3 de Transcrição de Octâmero/genética
20.
Sensors (Basel) ; 21(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668282

RESUMO

Cloud computing offers the services to access, manipulate and configure data online over the web. The cloud term refers to an internet network which is remotely available and accessible at anytime from anywhere. Cloud computing is undoubtedly an innovation as the investment in the real and physical infrastructure is much greater than the cloud technology investment. The present work addresses the issue of power consumption done by cloud infrastructure. As there is a need for algorithms and techniques that can reduce energy consumption and schedule resource for the effectiveness of servers. Load balancing is also a significant part of cloud technology that enables the balanced distribution of load among multiple servers to fulfill users' growing demand. The present work used various optimization algorithms such as particle swarm optimization (PSO), cat swarm optimization (CSO), BAT, cuckoo search algorithm (CSA) optimization algorithm and the whale optimization algorithm (WOA) for balancing the load, energy efficiency, and better resource scheduling to make an efficient cloud environment. In the case of seven servers and eight server's settings, the results revealed that whale optimization algorithm outperformed other algorithms in terms of response time, energy consumption, execution time and throughput.

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