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1.
RSC Adv ; 14(36): 26050-26058, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39161431

RESUMO

The detection of heavy metal ions, particularly Hg2+, has gained significant attention due to their severe adverse effects on human health and ecosystems. Conventional methods for monitoring these metals in freshwater often suffer from limitations in sensitivity, accuracy, and cost-effectiveness. This work introduces a novel heavy metal sensor based on Tamm resonance within a one-dimensional (1D) porous TiO2 photonic crystal structure. The sensor design includes a prism, a silver (Ag) layer, a cavity, and a ternary multilayer porous TiO2 layer. Reflectance spectra are analyzed using the transfer matrix method. A key aspect of this study is the optimization of sensor performance, which involves adjusting the thicknesses of all layers and the porosity of the multilayer porous TiO2. This optimization strategy is critical for achieving high sensitivity. The results demonstrate that the optimized sensor exhibits a high sensitivity of 0.045 nm ppm-1 for Hg2+ solutions. This sensitivity arises from the effective integration of Tamm resonance with the properties of the porous TiO2 photonic crystal. The proposed structure shows great potential for applications in heavy metal sensing, especially for detecting Hg2+ ion contamination in drinking water with high sensitivity and accuracy. In addition to its high performance, the photonic crystal sensor offers extended lifetime, rapid measurement capabilities, cost-effectiveness, and potential for integration into compact devices, making it a promising solution for environmental monitoring and water quality assessment.

2.
Sci Rep ; 14(1): 1015, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200033

RESUMO

The detection of heavy metals in water, especially Pb2+ ions, is important due to their severe hazardous effects. To address this issue, a highly controlled hexagonal TiON/TiO2 heterostructure has been synthesized in this study. The fabrication process involved the utilization of atomic layer deposition and direct current sputtering techniques to deposit TiO2 and TiON layers onto a porous Al2O3 membrane used as a template. The resulting heterostructure exhibits a well-ordered hollow tube structure with a diameter of 345 nm and a length of 1.2 µm. The electrochemical sensing of Pb2+ ions in water is carried out using a cyclic voltammetry technique under both light and dark conditions. The concentration range for the Pb2+ ions ranges from 10-5 to 10-1 M. The sensitivity values obtained for the sensor are 1.0 × 10-6 in dark conditions and 1.0 × 10-4 in light conditions. The remarkable enhancement in sensitivity under light illumination can be attributed to the increased activity and electron transfer facilitated by the presence of light. The sensor demonstrates excellent reproducibility, highlighting its reliability and consistency. These findings suggest that the proposed sensor holds great promise for the detection of Pb2+ ions in water, thereby facilitating environmental monitoring, water quality assessment, and safety regulation across various industries. Furthermore, the eco-friendly and straightforward preparation techniques employed in its fabrication provide a significant advantage for practical and scalable implementation.

3.
Sci Rep ; 11(1): 11830, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34088915

RESUMO

We formulate the tripartite entropic uncertainty relation and predict its lower bound in a three-qubit Heisenberg XXZ spin chain when measuring an arbitrary pair of incompatible observables on one qubit while the other two are served as quantum memories. Our study reveals that the entanglement between the nearest neighbors plays an important role in reducing the uncertainty in measurement outcomes. In addition we have shown that the Dolatkhah's lower bound (Phys Rev A 102(5):052227, 2020) is tighter than that of Ming (Phys Rev A 102(01):012206, 2020) and their dynamics under phase decoherence depends on the choice of the observable pair. In the absence of phase decoherence, Ming's lower bound is time-invariant regardless the chosen observable pair, while Dolatkhah's lower bound is perfectly identical with the tripartite uncertainty with a specific choice of pair.

4.
Sci Rep ; 11(1): 2457, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510178

RESUMO

Sleep disturbances are commonly reported by patients with asthma. However, the prevalence of sleep disturbance and its association with the level of asthma control is unknown. The primary objective was to determine the prevalence of sleep disturbance among Saudi adult asthmatic patients attending pulmonary clinics at King Abdulaziz Medical City (KAMC). The study also aimed to compare sleep quality between controlled and uncontrolled asthma patients. The study was carried out in the outpatient pulmonary clinics at KAMC and utilized a cross-sectional survey. The survey included five different questionnaires: asthma control test and questionnaires related to the quality of sleep (Pittsburgh sleep quality index [PSQI], Epworth sleepiness scale [ESS], Berlin questionnaire [a measure of obstructive sleep apnea risk], and insomnia severity index [ISI]). Among the 200 asthma patients, 66% suffered from poor sleep quality (PSQI > 5), 43% were at high risk for obstructive sleep apnea, 25% had excessive daytime sleepiness (ESS > 10), and 46.5% had significant clinical insomnia (ISI ≥ 10). Poor sleep quality was less common in patients with well-controlled asthma (37%) compared to those with partially controlled asthma (78%) and uncontrolled asthma (82%) (p < 0.001). Poor sleep quality was common among patients with asthma, particularly those with suboptimal levels of asthma control. Further studies are needed to better understand the interaction between these two conditions.


Assuntos
Asma/complicações , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/etiologia , Centros de Atenção Terciária , Distúrbios do Sono por Sonolência Excessiva/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Sono/fisiologia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Transtornos do Sono-Vigília/fisiopatologia
5.
Drug Res (Stuttg) ; 64(11): 617-22, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24500731

RESUMO

Accurate, precise, and sensitive LC-MS/MS assay method for the determination of montelukast (MO) in human plasma samples using gliclazide (GL) as internal standard was developed and applied in pharmacokinetics study.MO extracted by protein precipitation using acetonitrile. Chromatographic separation was carried out using a Agilant Triple quadrupoles mass spectrometer with API source with an Agilant SB- C18 (50×4.6 mm), 1.8 µm particle size column. A mobile phase consisting of acetonitrile: 0.1% formic acid (84:16) was delivered. Calibration curves were linear in the concentration range of (10.00-800.00) ng/ml. The bioanalytical method for determination of MO was successfully applied to assess pharmacokinetics of montelukast. The LLOQ was sensitive enough for detecting terminal phase concentrations of the drug. This study showed that developed method is suitable for MO pharmacokinetic study.


Assuntos
Acetatos/farmacocinética , Cromatografia Líquida/métodos , Antagonistas de Leucotrienos/farmacocinética , Quinolinas/farmacocinética , Espectrometria de Massas em Tandem/métodos , Acetatos/efeitos adversos , Adulto , Ciclopropanos , Humanos , Masculino , Quinolinas/efeitos adversos , Sulfetos
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