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1.
Med Gas Res ; 13(4): 187-191, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37077116

RESUMO

A primary concern for anesthesiologists is the maintenance of oxygenation during general anesthesia. Extending the safe apnea time, which is the time from the onset of apnea until the oxygen saturation concentration reaches 90% or less, increases the margin of safety with tracheal intubation. Preoxygenation before anesthetic induction has been a widely accepted manoeuver to increase oxygen reserves and hence delay the onset of arterial desaturation during apnea. This study aimed to evaluate the efficacy of pressure support ventilation with/without positive end-expiratory pressure (PEEP) for preoxygenation in adult patients. A total of 132 patients, aged 20 to 50 years, scheduled for elective surgery under general anesthesia, requiring endotracheal intubation, were included and randomly divided into three groups (n = 44 per group): spontaneous ventilation (SV), pressure support ventilation without PEEP (PS), and pressure support ventilation with PEEP (PEEP) groups. In the SV group, the patients breathed spontaneously without any support using a face mask; in the PS group, the patients breathed spontaneously with the inspiratory pressure support of 12 cm H2O without PEEP; and in the PEEP group, the patients were subjected to preoxygenation (similar to the PS group) with PEEP at 6 cm H2O. Preoxygenation was terminated when the fraction of expired oxygen reached 90% and the duration was recorded. Time from 90 seconds after administration of rocuronium bromide until oxygen saturation fell to 93% was recorded and taken as safe apnea time. The time taken for preoxygenation (the expired oxygen fraction reaches 90) was significantly shorter in patients of PEEP and PS groups when compared to the SV group. The safe apnea time was significantly longer in patients of PEEP and PS groups compared with the SV group. Application of inspiratory pressure support of 12 cm H2O and PEEP of 6 cm H2O during preoxygenation significantly reduces the preoxygenation time and prolongs the safe apnea time compared with conventional preoxygenation.


Assuntos
Apneia , Respiração com Pressão Positiva , Humanos , Adulto , Apneia/terapia , Estudos Prospectivos , Anestesia Geral , Oxigênio
2.
Heart Fail Rev ; 27(2): 431-454, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34245424

RESUMO

Heart failure is a global health burden responsible for high morbidity and mortality with a prevalence of greater than 60 million individuals worldwide. One of the major causes of heart failure is dilated cardiomyopathy (DCM), characterized by associated systolic dysfunction. During the last few decades, there have been remarkable advances in our understanding about the genetics of dilated cardiomyopathy. The genetic causes were initially thought to be associated with mutations in genes encoding proteins that are localized to cytoskeleton and sarcomere only; however, with the advancement in mechanistic understanding, the roles of ion channels, Z-disc, mitochondria, nuclear proteins, cardiac transcription factors (e.g., NKX-2.5, TBX20, GATA4), and the factors involved in calcium homeostasis have also been identified and found to be implicated in both familial and sporadic DCM cases. During past few years, next-generation sequencing (NGS) has been established as a diagnostic tool for genetic analysis and it has added significantly to the existing candidate gene list for DCM. The animal models have also provided novel insights to develop a better treatment strategy based on phenotype-genotype correlation, epigenetic and phenomic profiling. Most of the DCM biomarkers that are used in routine genetic and clinical testing are structural proteins, but during the last few years, the role of mi-RNA has also emerged as a biomarker due to their accessibility through noninvasive methods. Our increasing genetic knowledge can improve the clinical management of DCM by bringing clinicians and geneticists on one platform, thereby influencing the individualized clinical decision making and leading to precision medicine.


Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , Animais , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/genética , Testes Genéticos/métodos , Insuficiência Cardíaca/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação
3.
Environ Sci Pollut Res Int ; 29(17): 25318-25335, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34841485

RESUMO

Economic activities, technological innovation and diffusion, energy consumption and financial development have been significant in BRICS countries over the last three decades. Corresponding to it, BRICS have been facing substantial environmental deterioration. The growth of such factors needs a comprehensive analysis. Hence, this paper examines the impact of technological innovation and diffusion, renewable and non-renewable energy consumption and financial development on ecological footprint under the Kuznets framework in BRICS countries over the time from 1990 to 2018. To confirm the long- and short-run relationship, we apply the second-generation and heterogeneity panel techniques. Where, to measure the impact of technological innovation and diffusion, energy consumption and financial development and other control variable on ecological footprint we use Westerlund Co-integration and pooled mean group (PMG) model for this interest. The results reveal that technological diffusion and non-renewable energy consumption deteriorate environmental quality in the long run. In contrast, renewable energy and technological innovation improve environmental sustainability/quality significantly. Further, results also confirm the existence of the EKC hypothesis. The study suggests that the government should encourage technological innovation and renewable energy consumption to improve environmental quality and achieve the sustainable development goal (SDG).


Assuntos
Desenvolvimento Econômico , Invenções , Dióxido de Carbono , Difusão , Energia Renovável
4.
J Econ Struct ; 10(1): 28, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956816

RESUMO

This study aims to evaluate the impact of economic structure on the Environmental Kuznets Curve (EKC) in India. The present study deviates from the bulk of study in the literature with the incorporation of both aggregated and disaggregated measures of economic development on the environmental degradation function. For the empirical analysis, the study employed the Auto-Regressive Distributed Lag (ARDL) bounds testing approach of cointegration to analyse the long-run and short-run relationship during 1971-2014. Further, the direction of the causality is investigated through the Wald test approach. The results revealed that the conventional EKC hypothesis does not hold in India in both aggregated and disaggregated models since economic growth and its component have a U-shaped impact on the environmental quality in India. However, the effect of population on environmental quality is positive but not significant in the aggregated model. Whereas, in the disaggregated model, it is significantly affecting environmental quality. Hence, it is possible to infer that the population of the country increases, the demand for energy consumption increase tremendously, particularly consumption of fossil fuel like coal, oil, and natural gas, and is also evident from the energy structure coefficient from both models. This increase is due to the scarcity of renewable energy for meeting the needs of people. On the contrary, urbanization reduces environmental degradation, which may be due to improved living conditions in terms of efficient infrastructure and energy efficiency in the urban area leading to a negative relation between urbanization and environmental degradation.

5.
Dalton Trans ; 50(15): 5197-5207, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33881075

RESUMO

A facile chemical route is reported for synthesizing red-emitting photoluminescent/MRI multi-functional KLa(0.95-x)GdxF4:Eu3+ (x = 0 to 0.4) bio-compatible nanomaterials for targeted in vitro tumor imaging. Hexagonal phase pure nanoparticles show a significant and systematic change in morphology with enhanced photoluminescence due to the substitution of La3+ with Gd3+ ions. Single phase ß-KLa(0.95-x)GdxF4:Eu3+ exhibits multifunctional properties, both intense red emission and strong paramagnetism for high-contrast bioimaging applications. These silica capped magnetic/luminescent nanoparticles show long-term colloidal stability, optical transparency in water, strong red emission, and low cytotoxicity. The cellular uptake of coated nanoparticles was investigated in liver cancer cell line Huh-7. Our findings suggest that these nanoparticles can serve as highly luminescent imaging probes for in vitro applications with potential for in vivo and live cell imaging applications.


Assuntos
Antineoplásicos/química , Neoplasias Hepáticas/diagnóstico por imagem , Substâncias Luminescentes/química , Nanopartículas/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Európio/química , Flúor/química , Gadolínio/química , Humanos , Elementos da Série dos Lantanídeos/química , Substâncias Luminescentes/síntese química , Substâncias Luminescentes/farmacologia , Tamanho da Partícula , Potássio/química , Células Tumorais Cultivadas
6.
Dalton Trans ; 49(29): 10058-10068, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32657304

RESUMO

Systematic and strong rare-earth photoluminescence (PL) color flips that are highly sensitive to structural phase transformation in KLaF4:RE3+ (RE3+ = Eu3+, Er3+/Yb3+) nanocrystals are demonstrated. Room-temperature wet chemical synthesis at various reaction times involves a systematic conversion from cubic (α, space group Fm3[combining macron]m) to hexagonal (ß, space group P6[combining macron]2m) polymorph nanocrystals of 4 to 8 nm sizes. The unusual down-conversion photoluminescence (DC-PL) asymmetric ratio of the hypersensitive transition (5D0→7F2, Red) to that of nearly invariant transition (5D0→7F1, Orange) (R/O from 1.2 to 3.0) of KLaF4:Eu3+ is substantially affected by the site-selective occupancy and local symmetry around the Eu3+ ions, according to crystal packing transformation. The NIR excited up-conversion photoluminescence (UC-PL) of Er3+ ions produces a strong color flip from green (2H11/2 and 4S3/2) to red (4F9/2) dominated emissions based on their cubic or hexagonal crystal packing. The site occupancy and phonon energies strongly influence various nonlinear energy transfer mechanisms within RE3+ ion energies and the results are explained accordingly. The present study substantially reveals the local host effects and these two distinct polymorph nanoparticles can be potentially utilized for color-specific studies related to applications such as color-specific biological in vitro and in vivo imaging and other optoelectronic device applications.

7.
J Nanosci Nanotechnol ; 20(6): 3854-3858, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748086

RESUMO

An unconventional red-shift but enhanced photoluminescence (PL) under ultraviolet A (UV-A) irradiation of Eu2+ doped Barium Magnesium Aluminate (BAM) phosphor prepared in both bulk and nanoforms useful for modern lighting applications has been presented. The solid-state reaction and solution combustion approaches were used for the preparation of phosphors with post-annealing step in reduced atmosphere. A significant broad blue-green (˜500 nm) PL associated with the transition of Eu2+ from 4f6 5d1 excited state to the 4f7 ground state has been observed. The observed shifts and PL intensities were found to be extremely reliant on the thermal processing parameters during the synthesis of phosphor/nanophosphormaterials. It's also important to note that the size of the phosphor particles have significant role in defining the red-shift of PL due to quantum confinement effect. Detailed structural and morphological characterizations were also done in this paper. The results are promising and suggest that the BAM phosphor is highly desirable for enhancing the brightness levels in modern lighting and display systems.

8.
ACS Omega ; 4(1): 2275-2282, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459470

RESUMO

Heavily doped nanocrystals of host KLaF4 with rare earth (RE3+ = Er3+, Tm3+, and Yb3+) ions prepared by a simple one-step template-free wet-chemical route have been reported. Prepared KLaF4 nanocrystals reveal phase-pure cubic structures (lattice constant a = 5.931Å) with space group Fm3m. Precisely defined molar ratios of heavily dopant RE3+ ions allow us to achieve wide color upconversion (UC) emission tunability (blue, green to yellow-orange-red) and white light, without any morphology and structure changes. The enhanced red emission by a factor of ∼120 has been achieved in 20% Yb3+ and 5% Tm3+ ions in KLaF4:1% Er3+ nanocrystals, which is due to an efficient sensitizer-acceptor (Yb3+ to Er3+ and Tm3+ ions) energy transfer and interexchange energy process between acceptors. For the first time, the key role of sensitizer (Yb3+) for UC emission energy transfer to Er3+ and/or Tm3+ is experimentally demonstrated. The evidence of upconversion photoluminescence excitation spectra reveals a broad safe biological excitation window (690-1040 nm), which can be well demonstrated by low-cost NIR diode lasers/LEDs. The applicability of these cubic nanophosphors is demonstrated as light-emitting polymer composite coatings and blocks for LEDs and solar cell panels. These well-dispersed UC nanocrystals can also be found to have greater use in bioimaging and spectral studies.

9.
Environ Monit Assess ; 186(9): 5911-20, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24859859

RESUMO

Biomass is an important entity to understand the capacity of an ecosystem to sequester and accumulate carbon over time. The present study, done in collaboration with the Delhi Forest Department, focused on the estimation of growing stock and the woody biomass in the so-called lungs of Delhi--the Asola-Bhatti Wildlife Sanctuary in northern Aravalli hills. The satellite-derived vegetation strata were field-inventoried using stratified random sampling procedure. Growing stock was calculated for the individual sample plots using field data and species-specific volume equations. Biomass was estimated from the growing stock and the specific gravity of the wood. Among the four vegetation types, viz. Prosopis juliflora, Anogeissus pendula, forest plantation and the scrub, the P. juliflora was found to be the dominant vegetation in the area, covering 23.43 km(2) of the total area. The study revealed that P. juliflora forest with moderate density had the highest (10.7 m(3)/ha) while A. pendula forest with moderate density had the lowest (3.6 m(3)/ha) mean volume. The mean woody biomass was also found to be maximum in P. juliflora forest with moderate density (10.3 t/ha) and lowest in A. pendula forest with moderate density (3.48 t/ha). The total growing stock was estimated to be 20,772.95 m(3) while total biomass worked out to be 19,366.83 t. A strong correlation was noticed between the normalized difference vegetation index (NDVI) and the growing stock (R(2) = 0.84)/biomass (R(2) = 0.88). The study demonstrated that growing stock and the biomass of the woody vegetation in Asola-Bhatti Wildlife Sanctuary could be estimated with high accuracy using optical remote sensing data.


Assuntos
Biodiversidade , Monitoramento Ambiental/métodos , Árvores/crescimento & desenvolvimento , Biomassa , Carbono/análise , Conservação dos Recursos Naturais/métodos , Ecossistema , Índia , Árvores/classificação
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