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1.
Artigo em Inglês | MEDLINE | ID: mdl-38941133

RESUMO

CONTEXT: Investigating the co-occurrence of obstructive sleep apnea (OSA) and primary aldosteronism (PA) is crucial for understanding their interrelation. OBJECTIVE: This work aimed to evaluate the prevalence of OSA in individuals diagnosed with PA and to assess the prevalence of PA within the OSA population, with a specific focus on hypertensive individuals. METHODS: An exhaustive search was performed across PubMed, Embase, CINAHL, Scopus, and Web of Science up to September 2023, without restrictions on language or publication date. Studies were selected based on their focus on the prevalence of OSA in PA patients and vice versa, specifically in hypertensive individuals. Data were extracted using standard guidelines, focusing on patient characteristics, prevalence rates, and other relevant clinical parameters. RESULTS: Proportional meta-analysis using a random-effects model revealed a 59.8% prevalence of OSA in hypertensive PA patients, with 45.4% exhibiting moderate-to-severe OSA. Meta-regression showed no significant effect of age, sex, body mass index, antihypertensive medication, systolic blood pressure, diastolic blood pressure, or serum potassium on OSA prevalence. However, a significant positive association was found with the glomerular filtration rate (GFR) (P < .001). Subgroup analysis also revealed that a hyperfiltration rate (GFR ≥ 100 mL/min per 1.73 m2) may be associated with a higher prevalence of OSA (71%, P value for interaction < .01). Among hypertensive OSA patients, 11.2% had PA. CONCLUSION: A substantial prevalence of OSA in individuals with PA was identified, demonstrating a complex interplay between these conditions in hypertensive patients. Notably, the prevalence of OSA was significantly associated with kidney hyperfiltration.

2.
Opt Lett ; 48(5): 1188-1191, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36857245

RESUMO

In this work, the thermo-optic coefficient (TOC) of the silicon-rich amorphous silicon carbide (a-SiC) thin film deposited by plasma-enhanced chemical vapor deposition (PECVD) was characterized. We found that the TOC of the film increases as its silicon content increases. A more than threefold improvement in the TOC was measured, reaching a TOC as high as 1.88×10-4 ∘C-1, which is comparable to that of crystalline silicon. An efficient thermo-optic phase shifter has also been demonstrated by integrating the silicon-rich a-SiC micro-ring structure with a NiCr heater. Tunability of 0.117 nm/mW was demonstrated, and a corresponding tuning efficiency P π as low as 4.2 mW has been measured at an optical wavelength of 1550 nm. These findings make silicon-rich a-SiC a good candidate material for thermo-optic applications in photonic integrated circuits.

4.
Sensors (Basel) ; 16(12)2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27983694

RESUMO

A metal-semiconductor-metal ultraviolet photodetector has been fabricated with a radiofrequency (RF)-sputtered InGaO thin film. Results for the devices fabricated under different oxygen partial pressure are here in discussed. Under low oxygen partial pressure, the devices work in the photoconductive mode because of the large number of subgap states. Therefore, the devices exhibit internal gain. These defects in the films result in slow switching times and lower photo/dark current ratios. A higher flow ratio of oxygen during the sputtering process can effectively restrain the oxygen vacancies in the film. The responsivity of the photodetector fabricated under an oxygen flow ratio of 20% can reach 0.31 A/W. The rise time and decay time can reach 21 s and 27 s, respectively.

5.
Chemosphere ; 65(1): 141-7, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16574193

RESUMO

Avoiding substrate inhibition is a significant challenge in designing biological treatment systems for concentrated or toxic wastes. Substrate inhibition is commonly avoided by diluting the waste before treatment, however, dilution of a waste before treatment is not always feasible. In the case of radioactive mixed wastes and chemical warfare materiel (CWM), dilution presents regulatory and safety concerns. In this study, we investigated a "drip-feed" reactor configuration as an alternative approach for the biological treatment of concentrated waste streams with minimal dilution and complete containment. In the drip-feed reactor undiluted waste is slowly fed to biomass in a reactor at a rate sufficient to maintain activity, but at a low enough rate so that bacterial degradation maintains the reactor concentration below the toxic threshold. The reactor has no effluent, but rather fills as the undiluted waste is fed to the reactor, which has the advantage of preventing the release of hazardous material into the environment during treatment. Volatile releases are prevented with the use of condensers. The drip-feed bioreactor configuration was tested under aerobic conditions, at 25 degrees C, using a 10% acetonitrile feed solution. The treatment of acetonitrile to less than 0.1 mg l(-1) was achieved with a dilution factor of only 3.4. The acetonitrile degradation reaction was pH sensitive, where the optimal pH range for the biodegradation process was approximately between 6.5 and 7.1 and the biodegradation rate declined precipitously above pH 7.2. The applicability of the drip-feed reactor configuration to the treatment of mixed wastes and CWM is discussed.


Assuntos
Reatores Biológicos , Poluentes Ambientais/análise , Resíduos Perigosos/análise , Eliminação de Resíduos Líquidos/métodos , Acetonitrilas/química , Aerobiose , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Concentração de Íons de Hidrogênio , Oxirredução , Soluções
6.
Artigo em Inglês | MEDLINE | ID: mdl-16401570

RESUMO

To resolve mixed organic and radioactive waste disposal problems, Lawrence Berkeley National Laboratory (LBNL) initiated a treatability study using the catalytic chemical oxidation (CCO) system to oxidize a mixed-waste stream and to confine tritium as part of LBNL's pollution prevention program. LBNL has also adopted a legal approach by seeking an equivalent waste-treatment determination for the CCO process, and by petitioning the United States Environmental Protection Agency (EPA) to delist F-coded treatment residues. The results of this study demonstrate that (1) the CCO process can treat aqueous wastes containing a broad range of organic chemicals and achieve more than 99.999% destruction efficiency; (2) greater than 99.9% trapping efficiency for tritiated water can be achieved using an emission-reduction system that also confines the vapor of hydrochloric acid or nitric acid to the liquid residue; and (3) neutralized treatment residues can be disposed of as low-level radioactive waste at a permitted facility after EPA has approved LBNL's petitions, or the tritium in the residues can be recycled. The high oxidation efficiency of the CCO process is mainly due to the optimized operating conditions of the CCO process and the combined effect of steam reforming in the oxidation cell and the catalytic oxidation of organic mixtures and CO in the Pt/Al2O3 catalyst bed.


Assuntos
Resíduos Radioativos , Eliminação de Resíduos Líquidos/métodos , Catálise , Compostos Orgânicos , Oxirredução , Contaminação Radioativa da Água/prevenção & controle
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