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1.
Soc Sci Med ; 343: 116603, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38281387

RESUMEN

Education plays a significant role in shaping cognitive functioning throughout an individual's life. However, existing research has not adequately explored how the educational attainment of the spouse can impact cognitive functioning over time. This study presents one of the first longitudinal analyses of how spousal education is linked to cognitive trajectories of each member within couples during their later life in the United States. Guided by the linked lives perspective, we analyze data from 8370 couples in the Health and Retirement Study spanning from 2000 to 2018. Results from the Actor-Partner Interdependence Model (APIM) integrated with latent growth curve models reveal that cognitive trajectories exhibit a correlation between spouses over time. Moreover, our analysis uncovers gender-specific effects of spousal education on cognition, shedding light on the underlying mechanisms driving this connection. Notably, the lower educational attainment of husbands is associated with a faster cognitive decline in both themselves and their wives. This association is partially explained by economic resources, but not by health and social behaviors. The lower educational attainment of wives is linked to their own faster cognitive decline as well as lower initial cognitive levels of their husbands, in part via economic resources. However, wives' educational attainment is largely unrelated to their husbands' cognitive decline. Intriguingly, wives' education has a more pronounced impact on the health and social behaviors of their husbands than vice versa, although these health and social behaviors do not appear to influence husbands' cognitive decline. In conclusion, these results underscore the importance of considering spousal education in comprehending the complexities of cognitive decline within dyadic relationships.


Asunto(s)
Disfunción Cognitiva , Esposos , Humanos , Estados Unidos , Esposos/psicología , Disfunción Cognitiva/epidemiología , Jubilación , Cognición , Escolaridad , Matrimonio/psicología
2.
Opt Express ; 31(17): 27894-27904, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37710855

RESUMEN

A doping optimization model towards lower loss and higher efficiency at the target operating current is investigated. This model considers the effect of doping concentration on the series resistance and the internal loss. 780 nm lasers doped with a normal doping profile (Dop_normal) and an optimized doping profile (Dop_optimize) are both designed and fabricated. After doping optimization, the power loss decreased by 17%, the output power of the lasers increased by 26% and the electro-optical conversion efficiency increased by 22%. The model provides significant theoretical guidance for the optimization of the laser doping.

3.
Opt Express ; 31(17): 27927-27934, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37710858

RESUMEN

We propose and experimentally demonstrate that the lasing power and characteristic temperature (T0) of 905 nm semiconductor lasers can be optimized by use of the high strain quantum well (HSQW). To fix the lasing wavelength around 905 nm, HSQW with a higher ndium (In) content of the InGaAs gain material than that of the commonly used low strain quantum well (LSQW) requires a thickness-reduced quantum well. Thus, the HSQW has the following two advantages: stronger quantum size effects caused by the deep and thin quantum well, and higher compressive strain caused by a high In content of the InGaAs gain material. With the similar epitaxial structure, laser diodes with HSQW have a characteristic temperature T0 of 207 K and can deliver a higher lasing power with less power saturations. The high strain quantum well optimization method can be extended to other laser diodes with a wavelength near 900 nm with low In content InGaAs quantum wells and other similar low-strain gain material systems.

4.
Geriatrics (Basel) ; 8(4)2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37489317

RESUMEN

We provide one of the first nationally representative studies to examine COVID-19 vaccine uptake differences by marital status within the first year after the vaccine was recommended among older Americans. Data were drawn from the National Health and Aging Trends Study (2021). The study sample included 3180 participants aged 65 and older with 1846 women and 1334 men. Results from logistic regression models suggest that divorced/separated older adults were less likely to receive at least one dose of the COVID-19 vaccine in 2021 than their married counterparts, especially among women and individuals with higher education. Widowed and never married respondents were generally not significantly different from married respondents in COVID-19 vaccination status, with only one exception: less-educated never-married respondents were more likely to receive COVID-19 vaccination than their less-educated married counterparts. Our study highlights divorce/separation as a significant social factor associated with COVID-19 vaccine uptake among older adults in the U.S. These findings suggest that divorced/separated older adults are the most vulnerable population segment at risk of low COVID-19 vaccine uptake. Future efforts to improve vaccine equity and uptake should target this group specifically, with tailored interventions to increase their access and uptake of the vaccine.

5.
Opt Lett ; 47(19): 5012-5015, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36181174

RESUMEN

In this Letter, a new, to the best of our knowledge, external cavity structure based on double wavelength division multiplexing external cavities is proposed and demonstrated. The electro-optical conversion efficiency is improved and the brightness of the spectral beam combining diode lasers is enhanced. One wavelength division multiplexing external cavity is placed on the rear-side of the laser emitters to provide the strong optical feedback for wavelength locking and the other wavelength division multiplexing external cavity is placed on the front-side of laser emitters to combine three emitter beams to one beam. A maximum output power of up to 7.5 W is obtained and the brightness of the laser diode is 100 MW cm-2 sr-1 with an electro-optical conversion efficiency of 46.5%. Compared with a standard cavity for spectral beam combining, the use of double wavelength division multiplexing external cavities results in an electro-optical conversion efficiency improvement of 6.5%. The whole structure provides a new technology to achieve high-brightness and high electro-optical conversion efficiency for a laser diode source.

6.
J Aging Health ; 34(9-10): 1291-1301, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36120932

RESUMEN

OBJECTIVE: The study estimates the number of years after age 65 that Mexican Americans live with likely dementia and the impact of dementia on community-based services (CBS) use by nativity. METHODS: Using the Hispanic Established Populations for the Epidemiologic Studies of the Elderly Sullivan methods are employed to predict duration of dementia and logistic regressions identify the predictors of service utilization. RESULTS: Foreign-born women spend more years than other groups with dementia. The foreign-born are more likely to use out-of-home services, whereas U.S.-born are more likely to use in-home services. The foreign-born with dementia of relatively recent onset had the highest probability of service use. DISCUSSION: Given the high cost of institutional care and availability of family caregivers, community-based services are a potentially useful alternative for the growing Mexican-American population living with dementia. Expanded Medicaid and CBS programs could be an equitable and cost-effective alternative that should be investigated.


Asunto(s)
Demencia , Americanos Mexicanos , Estados Unidos , Humanos , Femenino , Anciano , Hispánicos o Latinos , Cuidadores , Servicio Social
7.
Chemistry ; 24(70): 18643-18647, 2018 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-30325545

RESUMEN

Differently from the normal three single precursor method to produce colloidal ternary quantum dots (QDs), herein ternary Ag3 SbS3 quantum dots (QDs) with efficient near-infrared (NIR) luminescence have been prepared by a new facile in situ conversion of Ag nanocrystals (NCs) with a binary Sb/S organic precursor Sb(C9 H19 COOS)3 under low temperature. The unprecedented construction evolution from Ag NCs to Ag3 SbS3 /Ag hetero-structure and final monodisperse Ag3 SbS3 QDs has been demonstrated. These novel Ag3 SbS3 QDs exhibit efficient NIR emission at ≈1263 nm and possess high colloidal stability.

8.
Artículo en Inglés | MEDLINE | ID: mdl-26724253

RESUMEN

The herbal preparation Ma-Xing-Gan-Shi-Tang (MXGST) is a popular traditional Chinese formulation that has been used for the treatment of coughs and fevers. The potential active components of MXGST are ephedrine, amygdalin, and glycyrrhizic acid. The aim of this study was to develop a validated analytical method to measure these analytes in the herbal preparation MXGST using ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Multiple reaction monitoring (MRM) was used to monitor m/z 166.1→148.1 for ephedrine ([M+H](+)), 475.2→163.0 for amygdalin ([M+NH4](+)), and 840.6→453.3 ([M+NH4](+)) for glycyrrhizic acid. The analytes were separated by a reverse phase C18 column (100×2.1mm, 2.6µm). The mobile phase consisted of 5mM ammonium acetate (0.1% formic acid) and 100% methanol (0.1% formic acid) with a linear gradient elution. Five brands of commercial pharmaceutical herbal products and a laboratory extract of MXGST were analyzed. Moreover, the modified UHPLC-MS/MS method was applied to the comparative pharmacokinetics of ephedrine in rats from the following three sources: (1) pure ephedrine, (2) an herbal extract of Ephedra, and (3) an herbal preparation of MXGST. Plasma samples from rats were prepared by protein precipitation, evaporation and reconstitution. The pharmacokinetic data showed that pure ephedrine was absorbed significantly faster than ephedrine of the Ephedra extract or the MXGST herbal preparation. However, the elimination half-life of ephedrine administered as the pure compound was 93.9±8.07min, but for ephedrine from the Ephedra extract and the MXGST, the half-lives were 133±17 and 247±57.6min, respectively. The area under the concentration curves (AUC) did not show significant differences among the three groups. These data suggest that the rest of the herbal ingredients in the Ephedra extract and the MXGST may provide a compensation effect that reduces the peak concentration of ephedrine and prolongs the elimination half-life.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Ephedra/química , Efedrina/farmacocinética , Medicina de Hierbas , Espectrometría de Masas en Tándem/métodos , Animales , Masculino , Ratas , Ratas Sprague-Dawley , Estándares de Referencia
9.
Artículo en Inglés | MEDLINE | ID: mdl-25861367

RESUMEN

According to a survey from the National Health Insurance Research Database (NHIRD), Jia-Wei-Xiao-Yao-San (JWXYS) is the most popular Chinese medicine for cancer patients in Taiwan. 5-Fluorouracil (5-FU) is a general anticancer drug for the chemotherapy. To investigate the herb-drug interaction of JWXYS on pharmacokinetics of 5-FU, a microdialysis technique coupled with a high-performance liquid chromatography system was used to monitor 5-FU in rat blood and brain. Rats were divided into four parallel groups, one of which was treated with 5-FU (100 mg/kg, i.v.) alone and the remaining three groups were pretreated with a different dose of JWXYS (600, 1200, or 2400 mg/kg/day for 5 consecutive days) followed by a combination with 5-FU. This study demonstrates that 5-FU with JWXYS (600 mg/kg/day or 1200 mg/kg/day) has no significant effect on the pharmacokinetics of 5-FU in the blood and brain. However, JWXYS (2400 mg/kg/day) coadministered with 5-FU extends the elimination half-life and increases the volume of distribution of 5-FU in the blood. The elimination half-life of 5-FU in the brain for the pretreatment group with 2400 mg/kg/day of JWXYS is significantly longer than that for the group treated with 5-FU alone and also reduces the clearance. This study provides practical dosage information for clinical practice and proves the safety of 5-FU coadministered with JWXYS.

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