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1.
Sci Rep ; 13(1): 22425, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38104190

RESUMO

Renewable energy integration introduces grid instability due to variable and intermittent sources like solar and wind, impacting reliability. This paper provides a thorough discussion of recent advancements and emerging trends in grid-integrated wind energy systems (GIWES) and grid-integrated solar energy systems (GISES). More than 70 research articles have been rigorously assessed and listed the technological and economic challenges. The increase in installations of grid-Integrating systems gives rise to challenges like as grid strain, peak shaving impacts, unpredictability of renewable energy sources (RES), and power quality disturbances. A variety of custom power devices, such as dynamic voltage restorers (DVR), static synchronous compensators (STATCOM), active power filters (APF), and unified power quality conditioners (UPQC), have gained popularity in response to these challenges. Among the various challenges, power quality disturbances, including voltage sag, swell, current and harmonics pose significant issues. To address these disturbances this work present a novel approach utilizing fuzzy logic (FL) to develop multi-feeder interline unified power-quality conditioners (MF-IUPQCs). The MF-IUPQC has three legs and three levels, each of which has four diode-clamped inverters. Switching is carried out through the use of space vector pulse width/duration modulation (SVPWM). Total harmonic distortion (THD) induced by nonlinear loads is reduced by the FLC-based MF-IUPQC, which also improves dynamic performance and offers a smooth DC-link voltage. The proposed control mechanism is implemented using MATLAB/Simulink. The fuzzy-based controller is compared to the industry-standard proportional-integral (PI) controller to determine its efficacy. Among them, the MF-IUPQC based on FLC delivers the smoothest voltage profile and the lowest THD.

2.
Matern Child Health J ; 27(10): 1705-1712, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37405559

RESUMO

INTRODUCTION: The quality of maternity care in Tamil Nadu has significantly improved in the past few years and various public health initiatives have helped to reduce crucial indicators like Maternal Mortality Ratio and Infant Mortality Rate. The improvement in quality of interface between the mothers and service providers in term of language, behaviour and attitude for ensuring 'Respectful Maternity Care' would support further enhancement of maternal and new born outcomes. Delivery of appropriate and respectful care to each pregnant woman would not only go a long way in reducing mortality and morbidity for the woman and new-born but also help in improved cognitive development of the baby. OBJECTIVE: To assess the quality of delivery care practices provided during normal delivery among women accessing public health facilities in Tamil Nadu. METHODS: A descriptive evaluation study was conducted from May to December 2018 in 16 facilities across 14 districts in Tamil Nadu. The health facilities were stratified according to the level of services, Government Medical College hospitals (MC), District headquarter hospitals (DHQ), Sub-district hospitals (SDH), and PHCs, 4 facilities in each category were selected. Data was collected by direct observation using a facility observation check list in an Android-based tablet application. Informed consent was obtained from all participants. RESULTS: A total of 1006 pregnant women out of 2242 women who had normal delivery were assessed and included in the study. More than 50% of deliveries were conducted by nurses and midwives and the perinatal and maternal outcomes were found to be good. The parameters for the respectful maternity care were recorded. Routine care monitoring parameters helped to reduce mortality rate and improved delivery care. CONCLUSION: The state though has achieved substantial success in promoting institutional delivery practices, still needs certain crucial improvements in the quality of respectful maternal care during the delivery.


The overall pooled prevalence of disrespectful maternity care in India was 71.31% (95% CI 39.84­102.78) where every individual study prevalence ranged from 20.9 to 100%. Institutional delivery is 100 percent in Puducherry and Tamil Nadu (NFHS V) and hence it is important to assess the quality of maternity care provided in public healthcare facilities in the state. The improvement in the quality of the interface between the women and service providers in terms of language, behavior, and attitude for ensuring 'Respectful Maternity Care' would thus contribute to positive outcomes for women and their newborns, and also to ensure the cognitive development of children later in life.


Assuntos
Serviços de Saúde Materna , Feminino , Gravidez , Humanos , Índia , Parto Obstétrico , Parto/psicologia , Instalações de Saúde , Atitude do Pessoal de Saúde , Qualidade da Assistência à Saúde
3.
Indian J Community Med ; 42(2): 94-96, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28553025

RESUMO

INTRODUCTION: Adolescence is a stressful period due to physical, psychological, sexual changes, and the presence of psychiatric disorders such as depression, anxiety, and stress at this stage of life is a matter of concern. OBJECTIVES: The objectives of the study were to determine the prevalences of depression, anxiety, and stress among higher secondary school students of Imphal and to determine the association between depression, anxiety, and stress and selected variables such as gender, standard, and religion. MATERIALS AND METHODS: From September 2014 to October 2014, a cross-sectional study was conducted among higher secondary school students of Imphal. The sample size was calculated to be 750. Seven schools were randomly selected, and all the students in that school were enrolled in the study. The study tool used was a questionnaire containing DASS (Depression Anxiety Stress Scale) and sociodemographic characteristics. RESULTS: The prevalences of depression, anxiety, and stress among 830 valid respondents were 19.5%, 24.4%, and 21.1%, respectively. In total, 81.6% of the respondents had at least one of the studied disorders and 34.7% of the respondents had all the three negative states. The prevalences of depression, anxiety, and stress were high among females and were significant for anxiety (P = 0.00) and stress (P = 0.04). The prevalences of depression and stress were significantly higher among 12th standard students with P-values of 0.00 and 0.02. CONCLUSION: The prevalences of depression, anxiety, and stress were high with anxiety and stress significantly higher among females, whereas prevalences of depression and stress were significantly higher among 12th standard students. More studies are recommended to determine the factors leading to these mental disorders.

4.
Microb Pathog ; 102: 120-132, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27919625

RESUMO

The present work reports the development of a Simple, rapid and eco-friendly route for the biosynthesis of gold and silver nanoparticles and their antimicrobial activity against gram positive and gram negative bacterial pathogens in the wound infected area. The synthesis was done using Mukia maderasapatna plant extract as a reducing agent. FT-IR analysis reported that the methanol extract was found to contain maximum number of functional groups which is responsible for the reduction of metal ions to metal nanoparticles. Further, the presence of bioactive molecules present in the methanol extract was confirmed by GC-MS analysis. The major phytochemical constituents observed in this Mukia maderaspatna leaf extract were n-hexadecanoic acid (15.51%), Octadecanoic acid (11.92%), stigmasterol (9.12%), Octadecanoic acid, 2, 3 hydroxypropyl ester (8.7%), Bicycloheptane, 2,6,6- trimethyl (5.57%) and stearic acid (4.23%). Initially, the formation of gold and silver nanoparticles was confirmed from their absorption spectra at 535 nm and 434 nm using UV- visible spectroscopy. The crystalline nature of the obtained gold and silver nanoparticles was confirmed by X-ray diffraction analysis. The average size of the gold and silver nanoparticles found around 50 nm and 20 nm respectively was confirmed by TEM analysis. The antimicrobial activities of silver and gold nanoparticles were checked against bacterial strains and the fungal strains. The formation of inhibition zones concluded that both the nanoparticles showed efficient antimicrobial activity against both the pathogens. Further, different concentrations of gold and silver nanoparticles, the antibiotics Ciprofloxacin and chloramphenicol as the positive control were carried out. The results concluded that the silver nanoparticles showed efficient activity against bacterial pathogens and fungal pathogens with the lowest concentration of 0.35 µg/ml and 0.45 µg/ml respectively.


Assuntos
Cucumis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Análise Espectral , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Ouro/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier
5.
J Pharm Bioallied Sci ; 3(2): 286-93, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21687360

RESUMO

OBJECTIVES: The purpose of this study was to investigate the anticancer activity of anticancer drugs (5-fluorouracil and 6-thioguanine) in polymeric nanocapsules in the presence and in the absence of gold and iron oxide nanoparticles toward Hep2 cancer cells. MATERIALS AND METHODS: MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay was used for quantitative measurements for the anticancer cell activity. Encapsulated drug in polyethylene terephthalate-polylactic acid copolymer (PET-co-PLA) nanocapsules in the presence and absence of gold and iron oxide nanoparticles were prepared via the W/O/W emulsification solvent-evaporation method. Morphology of the nanoparticles was characterized by transmission electron microscopy and scanning electron microscopy. CONCLUSION: The average size of the polymeric nanocapsules, gold nanoparticles, and iron oxide nanoparticles were found to be in range of 230-260, 18 -20 nm, 5-10 nm, respectively. The findings in this study inferred that incorporated drug in polymeric nanocapsules with gold nanoparticles and iron oxide nanoparticles show better anticancer activity when compared with encapsulated drug in polymeric nanocapsules.

6.
Analyst ; 135(9): 2348-54, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20596569

RESUMO

An electrochemical assay for sensing NO in biological systems is described in this paper. The ferrocene mediated reduction of NO, facilitated by the gold nanocomposite modified glassy carbon electrode is followed by an amperometric procedure. The analytical protocol involves the modification of a glassy carbon electrode by an overlayer of Au nanocomposites prepared through galvanic reduction. Additional overlayers can be built on the surface by repetition of the procedure. The modification leads to the decrease of the over-potential required for the analysis and results in a non-biofouling surface. Since the procedure is based on the electrochemical reduction of NO, the potential interferences from species like dopamine, ascorbic acid, etc., are overcome. The sensitivity, detection limit and response time achieved through this protocol for the modified electrode containing three Au overlayers are 0.03 nA/nM, 25.75 nM and <5 s. Analysis of NO has been carried out in real samples like liver extract, peripheral blood mononuclear cells (PBMCs) and miconazole nitrate ointment and the values obtained are comparable with that obtained by Griess analysis.


Assuntos
Carbono/química , Técnicas Eletroquímicas/métodos , Compostos Ferrosos/química , Ouro/química , Nanopartículas Metálicas/química , Óxido Nítrico/análise , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Extratos Celulares/química , Dendrímeros/química , Eletrodos , Nanopartículas Metálicas/ultraestrutura , Metalocenos , Oxirredução
7.
Appl Biochem Biotechnol ; 151(2-3): 132-42, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18975143

RESUMO

The polycyclic aromatic hydrocarbons (PAHs) biodegradation potential of the five basidiomycetes' fungal monocultures and their cocultures was compared with that of a Pseudomonas isolate recovered from oil-spilled soil. As utilization of hydrocarbons by the microorganisms is associated with biosurfactant production, the level of biosurfactant production and its composition by the selected microorganisms was also investigated. The Pseudomonas isolate showed higher ability to degrade three of the five PAHs but the isolate did not produce biosurfactant higher than C. versicolor and P. ostreatus. Among the PAHs, the most effective biodegradation of PAH--pyrene (42%)--was obtained with the fungus C. versicolor. Cocultures involving the fungi and Pseudomonas could not significantly degrade the selected PAHs compounds above that degraded by the most efficient monoculture. A slight increase in pyrene degradation was observed in cocultures of C. versicolor and F. palustris (93.7% pyrene). The crude biosurfactant was biochemically characterized as a multicomponent surfactant consisting of protein and polysaccharides. The PAH biodegradation potential of the basidiomycetes fungi positively correlated with their potential to express ligninolytic enzymes such as lignin peroxidase (Lip), manganese peroxidase (Mnp), and laccase. The present study utilized in silico method such as protein-ligand docking using the FRED in Open Eye software as a tool to assess the level of ligninolytic enzymes and PAHs interactions. The in silico analysis using FRED revealed that of the five PAHs, maximum interaction occurred between pyrene and all the three ligninolytic enzymes. The results of the in silico analysis corroborated with our experimental results showing that pyrene was degraded to the maximum extent by species such as C. versicolor and P. ostreatus.


Assuntos
Basidiomycota/metabolismo , Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Pseudomonas/metabolismo , Acenaftenos/metabolismo , Antracenos/metabolismo , Técnicas de Cocultura , Simulação por Computador , Fluorenos/metabolismo , Naftalenos/metabolismo , Pirenos/metabolismo , Poluentes do Solo/metabolismo , Tensoativos/química , Tensoativos/metabolismo
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