The effects of off-state breakdown on characteristics of power AlGaAs/InGaAs pseudomorphic HEMTs (PHEMTs) are investigated in detail. While the gate leakage current is substantially decreased after breakdown stress, no obvious changes in drain-to-source current and transconductance are observed. Prior to breakdown stress, gate leakage current shows a nearly ideal 1/f noise characteristic with an Ig/sup 2/ dependence, suggesting a surface generation-recombination current from the interface of the passivation layer. After stress, the gate current noise can be drastically reduced. The results suggest an alternative for alleviating the gate leakage current in PHEMTs.

Aims: To assess whether periconceptional exposure to glucagon‐like peptide‐1 receptor agonists (GLP‐1 RAs) is associated with adverse outcomes in women with pregestational type 2 diabetes. Materials and Methods: We linked Taiwan's Birth Certificate Application and National Health Insurance claims (2013–2022) to assemble a nationwide cohort of singleton births to mothers (18–50 years) with pregestational diabetes. Exposure was any GLP‐1 RA dispensed during the 90 days before and after the last menstrual period; insulin without GLP‐1 RA was the active comparator. Outcomes were major congenital malformations, stillbirth, preterm birth (<37 weeks) and small for gestational age (SGA, <10th percentile). We used 1:4 propensity‐score matching and Poisson generalised estimating equation (GEE); sensitivity analyses required ≥2 prescriptions and restricted exposure to the first trimester. Results: We identified 3351 comparison pregnancies (GLP‐1 RA 160; insulin 3191); matching yielded 160 versus 606. Risk ratios (GLP‐1 RA vs. insulin) were malformations 0.64 (95% confidence interval 0.11–3.83), stillbirth 2.05 (0.82–5.13), preterm birth 1.09 (0.85–1.39) and SGA 0.86 (0.31–2.41). Sensitivity analyses were similar. Conclusions: Periconceptional GLP‐1 RA exposure was not associated with increased risks of malformations, stillbirth, preterm birth or SGA versus insulin use. These preliminary data require confirmation in larger agent‐specific studies; until then, intentional GLP‐1 RA use in planned pregnancy is not advised.

Background: Denture use may contribute to maintaining cognitive function by addressing the masticatory difficulties caused by tooth loss. However, reports on the association between tooth loss and cognitive impairment have been inconsistent. The impact of changes in tooth number and denture use on the development of cognitive impairment in older adults remains unclear. This study aimed to evaluate these impacts among community-dwelling older adults. Methods: This 7-year longitudinal prospective cohort study included 64 520 community-dwelling Taiwanese older adults aged ≥65 years without cognitive impairment at baseline. The primary outcome was cognitive impairment assessed using the Short Portable Mental Status Questionnaire. Results: Older adults with 10–19, 1–9, and 0 teeth, including natural teeth and dentures, had higher risks of developing cognitive impairment than those with ≥20 teeth, with adjusted odds ratios (ORs) of 1.40 (95% confidence intervals [CIs], 1.14–1.71), 1.85 (95% CI, 1.40–2.43), and 2.56 (95% CI, 1.74–3.76), respectively. Furthermore, among those with 10–19 teeth (OR, 0.71; 95% CI, 0.52–0.98) or 1–9 teeth (OR, 0.43, 95% CI, 0.27–0.68) at baseline, an increase of more than 1 level in tooth number during follow-up (eg, from 10–19 to ≥ 20 teeth and dentures through the acquisition of dental prosthetics such as dentures, bridges, or implants) was associated with a lower risk of developing cognitive impairment compared with those with a stable tooth number. Conclusions: Our findings suggest that prompt denture use and maintaining >20 teeth (including natural teeth and dentures) mitigate the risk of cognitive impairment associated with tooth loss among community-dwelling older adults.

In 2020, Taiwan’s healthcare system faced a notable burden imposed by the coronavirus disease (COVID-19) pandemic. Emergency department (ED) is a high-risk area for severe acute respiratory syndrome coronavirus 2 transmission. The effect of COVID-19 on the utilization of ED services among frequent ED users remains unknown. This cohort study determined the impact of the COVID-19 pandemic on healthcare-seeking behaviors among frequent ED users at Taipei City Hospital, Taiwan. We included ED users aged ≥ 18 years admitted to Taipei City Hospital during February 2019–January 2020 (before the pandemic) and February 2020–January 2021 (during the pandemic). Frequent ED users were patients with four or more ED visits per year. Stepwise logistic regression was performed to identify predictors of frequent ED use during the COVID-19 pandemic. Frequent ED users had shorter hospital stays in the ED during the pandemic. After adjusting for sociodemographic factors and other covariates, patients with a triage status of level 4–5, pneumonia diagnosis, giddiness, or dyspnea were more likely frequent ED visitors during the COVID-19 pandemic. To reduce the risk of acquiring COVID-19, it is important to utilize territorial healthcare or telehealth to avoid inappropriate ED visits for patients with a low level of risk or chronic disease.

Chronic kidney disease (CKD) is a widespread condition in the global population and is more common in the elderly. Thyroid-stimulating hormone (TSH) level increases with aging, and hypothyroidism is highly prevalent in CKD patients. However, the relationship between low thyroid function and mortality in CKD patients is unclear. Therefore, we conducted a retrospective cohort study to examine the relationship between TSH elevation and all-cause mortality in elderly patients with CKD. This retrospective cohort study included individuals ≥65 years old with CKD (n = 23,786) in Taipei City. Health examination data from 2005 to 2010 were provided by the Taipei Databank for Public Health Analysis. Subjects were categorized according to thyroid-stimulating hormone (TSH) level as follows: low normal (0.34<TSH<1.074 mIU/L), middle normal (1.074≤TSH≤2.46 mIU/L), high normal (2.46<TSH<5.2 mIU/L), elevated I (5.2≤TSH<10 mIU/L), and elevated II (TSH≥10 mIU/L). Risk of mortality was evaluated using a Cox proportional hazard regression model adjusted for sex, age, hypertension, diabetes mellitus, CKD stage, serum albumin, high-density lipoprotein cholesterol, uric acid, hemoglobin, body mass index, glutamic-pyruvic transaminase, smoking, alcohol consumption, and history of cardiovascular disease (coronary artery disease, congestive heart failure, cerebral vascular disease), history of cancer, and history of chronic obstructive pulmonary disease. Our results showed that compared to the reference group (middle normal TSH), the risk of all-cause mortality was increased in the elevated I group (hazard ratio [HR], 1.21; 95% confidence interval [CI], 1.02–1.45) and elevated II group (HR, 1.30; 95% CI, 1.00–1.69). We found a significant association between TSH elevation and all-cause mortality in this cohort of elderly persons with CKD. However, determining the benefit of treatment for moderately elevated TSH level (5.2–10 mIU/L) in elderly patients with CKD will require a well-designed randomized controlled trial.

Mask usage is an effective measure to prevent severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection; however, mask reuse is not recommended. Studies examining the factors associated with mask reuse during the coronavirus disease (COVID-19) pandemic are limited. This nationwide survey aimed to determine the prevalence and factors associated with mask reuse among Taiwanese citizens during the pandemic. From 18 May through 31 May 2020, a computer-assisted telephone interview system was used to randomly select Taiwanese citizens for interview regarding COVID-19-preventive behaviors and knowledge on mask usage. For a total of 1075 participants, the overall mean age was 57.4 years, and 82.2% of participants reported mask reuse during the COVID-19 pandemic. After controlling for other covariates, participants who had a greater knowledge of mask usage or had a high supply of masks were less likely to reuse masks during the pandemic. Moreover, generalized estimating equations (GEE) analysis showed that, compared with the participants’ mask-wearing behaviors before the COVID-19 pandemic, they were more likely to reuse masks during the pandemic. Thus, it is imperative to educate people on the correct usage of masks. Furthermore, the government should provide sufficient masks to the general population to reduce mask reuse.