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1.
Materials (Basel) ; 17(5)2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38473462

ABSTRACT

Porous silicon (PSi) has promising applications in optoelectronic devices due to its efficient photoluminescence (PL). This study systematically investigates the effects of various organic solvents and their concentrations during electrochemical etching on the resulting PL and surface morphology of PSi. Ethanol, n-butanol, ethylene glycol (EG) and N,N-dimethylformamide (DMF) were employed as solvents in hydrofluoric acid (HF)-based silicon etching. The PL peak position exhibited progressive blue-shifting with increasing ethanol and EG concentrations, accompanied by reductions in the secondary peak intensity and emission linewidth. Comparatively, changes in n-butanol concentration only slightly impacted the main PL peak position. Additionally, distinct morphological transitions were observed for different solvents, with ethanol and n-butanol facilitating uniform single-layer porous structures at higher concentrations in contrast to the excessive etching caused by EG and DMF resulting in PL quenching. These results highlight the complex interdependencies between solvent parameters such as polarity, volatility and viscosity in modulating PSi properties through their influence on surface wetting, diffusion and etching kinetics. The findings provide meaningful guidelines for selecting suitable solvent conditions to tune PSi characteristics for optimized device performance.

2.
Article in English | MEDLINE | ID: mdl-36833615

ABSTRACT

Cities evolve and change with economic development and population growth, and urban planning laws in Taiwan have regulations that should be comprehensively reviewed every six years. Most current government policies aim to add new disaster prevention shelters or rescue stations. An economical way to improve the disaster prevention capabilities of urban planning is through examining or reviewing spatial structures and disaster prevention plans from the perspective of citizens or residents. The UN Office of Disaster Risk Reduction (UNDRR) launched the Making Cities Resilient Campaign policy to enhance disaster-resistant and sustainable urban environments through integrated disaster mitigation, reduction, response, and evacuation plans. This study used space syntax to ascertain evacuation route features using geometric distance analysis. There was 31.61% efficiency in relation to accessible roads on a comprehensive map. We could clearly see that since the areas in the first quadrant were relatively close to accessible roads, and there was an area that was not connected to the existing evacuation channels. The increased number of channels was more accessible and extensive. Such suggestions are helpful for government departments to prepare for disaster management. The spatial characteristics of the physical environment are explained by the accessibility and efficiency of axial maps and visibility analyzed by space syntax. Our findings reveal that space syntax is an important application when examining evacuation maps.


Subject(s)
Disaster Planning , Disasters , Cities , Environment , Spatial Analysis
3.
J Dent Sci ; 15(4): 526-535, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33505626

ABSTRACT

BACKGROUND/PURPOSE: We previously found that the partially purified 30-100 kDa fraction of areca-nut-extract (ANE 30-100K) induces autophagy in different types of cells including oral carcinoma OECM-1 cells. This study was to analyze the composition and possible mechanisms of ANE 30-100K-induced autophagy (AIA). MATERIALS AND METHODS: Phenol-sulfuric acid method and high performance anion exchange chromatography were utilized to analyze the composition of ANE 30-100K. OECM-1 and esophageal CE81T/VGH cells were taken as the experimental models. Microscope and transmission electron microscope were used to observe morphological changes. Cell viability and specific proteins were respectively measured by XTT and Western bot assay. shRNA and chemical inhibitors were applied to assess the involvement of Atg5, caveolin, and proteasome in AIA. RESULTS: ANE 30-100K contains ∼67% carbohydrate, which is composed of fucose (5.938%), arabinose (24.631%), glucosamine (8.066%), galactose (26.820%), glucose (21.388%), and mannose (13.157%). After ANE 30-100K stimulation, CE81T/VGH cells showed intracellular vacuoles, acidic vesicles, double-membrane vacuoles, and elevated LC3-II level. ANE 30-100K-induced cytotoxicity and LC3-II accumulation were significantly inhibited by Atg5 knockdown. Furthermore, the endocytosis inhibitor (methyl-ß-cyclodextrin) and two caveolin shRNAs, as well as two proteasome inhibitors (lactacystin and epoxomicin), were shown to significantly attenuate ANE 30-100K-induced cytotoxicity and LC3-II accumulation in both OECM-1 and CE81T/VGH cells. CONCLUSION: The major components of ANE 30-100K are carbohydrates. CE81T/VGH also exhibited autophagic responses to ANE 30-100K. Caveolin-mediated endocytosis and proteasome are involved in AIA. This study may have provided new knowledges of the action mechanisms and compositions of ANE 30-100K.

4.
Medicine (Baltimore) ; 98(50): e18190, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31852074

ABSTRACT

The purpose of this study was to evaluate the association between tocolysis for preterm uterine contraction and the risk of nonreassuring fetal status.This was a retrospective cohort study using data from the Taiwan National Health Insurance Research Database. Pregnant women were enrolled if they delivered a baby during January 1, 2003 to December 31, 2011. The occurrence of the nonreassuring fetal status was compared between pregnant women with and without tocolytic treatment for preterm uterine contraction. Multivariable logistic regression models with adjusted cofounders were used to evaluate the association between tocolysis and the risk of nonreassuring fetal status.Of 24,133 pregnant women, 1115 (4.6%) received tocolytic treatment during pregnancy. After adjusting for covariates, pregnant women receiving tocolysis more than one time during pregnancy were found to have significantly higher risk of the nonreassuring fetal status when compared with pregnant women who did not receive tocolysis for uterine contraction (Odds Ratio = 2.70, 95% Confidence Interval: 1.13-6.49).Pregnant women with more frequent tocolysis for preterm uterine contraction during pregnancy had an increased risk of nonreassuring fetal status. Close evaluation of dose and duration of tocolytic treatment is necessary for pregnant women with preterm uterine contraction.


Subject(s)
Fetal Distress/prevention & control , Obstetric Labor, Premature/prevention & control , Population Surveillance , Tocolysis/methods , Tocolytic Agents/therapeutic use , Adult , Female , Follow-Up Studies , Humans , Incidence , Infant, Newborn , Obstetric Labor, Premature/epidemiology , Pregnancy , Retrospective Studies , Taiwan/epidemiology
5.
Materials (Basel) ; 12(23)2019 Dec 02.
Article in English | MEDLINE | ID: mdl-31810318

ABSTRACT

Hybrid structures known as timber-steel composites (TSCs) have been extensively studied due to their potential use as alternative construction materials that can satisfy demands related to sustainability. In addition to load capacity, fire resistance is a major consideration regarding the extensive use of TSCs. In this study, 12 specimens were tested using a glulam timber material covering cold-formed steel at the center. Specifically, the TSCs were fabricated from two timber blocks and an I-shaped steel core assembled using dowels or glue as a major structure. In order to use additional timber as a fire protection layer to protect a major structure by its charcoal produced after being burned, an additional timber with 5 cm in thickness was used to cover the major structure. The 1-h fire testing of TSC following the ISO 834-1 standard was applied, in order to achieve the potential application for a 4-story timber building. The results showed that temperatures at the steel flange increased by more than 300 °C for the final 5 min in 10 out of the 12 TSC specimens, indicating that the fire protection provided by the timber structure was not sufficient. The charcoal layer surpassing the extra timber was originally set and entered the steel structure of the TSC, which was expected to retain its physical qualities after a fire. Methods for evaluating the charring properties, based on the conventional method for wood and the standard specification set by Eurocode 5, were used to assess the structural degradation of TSCs. The conventional assessments showed a divergence from the actual performance of TSCs. Such variations demonstrated the limitations of models for conventional wood in assessing the structure of a TSC. A realistic assessment was conducted to expand knowledge related to this composite under destructive processes and provide fire reference values for the practical implementation of TSCs.

6.
Pharmacotherapy ; 39(8): 798-808, 2019 08.
Article in English | MEDLINE | ID: mdl-31251824

ABSTRACT

STUDY OBJECTIVES: To evaluate the association between anticholinergic medication use, categorized by anticholinergic cognitive burden (primary objective) and cumulative dose (secondary objective), and the risk of developing dementia among patients with Parkinson's disease. DESIGN: Retrospective cohort study with an active comparator design. DATA SOURCE: National Health Insurance Research Database in Taiwan (2001-2011). PATIENTS: A total of 1232 adults with Parkinson's disease who were diagnosed between 2002 and 2004 and taking at least one antiparkinson medication during this period were included. Of these patients, 694 were exposed to anticholinergic medications categorized as mild (reference group), and 538 were exposed to anticholinergic medications categorized as moderate or severe (exposure group). MEASUREMENTS AND MAIN RESULTS: Exposure to different types of anticholinergic medications was categorized by using the Anticholinergic Cognitive Burden (ACB) scale, and cumulative doses of anticholinergic medications were measured by using the cumulative minimum doses (cMD) method. Associations between anticholinergic medication use and risk of dementia were assessed by multivariable Cox proportional hazards models. The type of anticholinergics used (moderate or severe vs mild ACB) was not significantly associated with an increased risk of developing dementia (hazard ratio [HR] 0.97, 95% confidence interval [CI] 0.72-1.27). After adjusting for confounders, a high cumulative dose of anticholinergic drug (> 1095 cumulative minimum doses [cMDs]) was found to be significantly associated with an increased risk of developing dementia when compared with a low cumulative dose of anticholinergic drug (≤ 90 cMDs) (HR 3.06, 95% CI 1.35-6.97). CONCLUSION: Among patients with Parkinson's disease in Taiwan, those with a high cumulative dose of anticholinergics had an increased risk of being diagnosed with dementia. Physicians should consider prescribing the lowest therapeutic dose of anticholinergic medication when making treatment decisions for patients with Parkinson's disease.


Subject(s)
Cholinergic Antagonists/adverse effects , Dementia/epidemiology , Parkinson Disease/drug therapy , Adult , Aged , Aged, 80 and over , Cholinergic Antagonists/administration & dosage , Cohort Studies , Dementia/chemically induced , Dementia/etiology , Female , Humans , Insurance Claim Review , Male , Middle Aged , Proportional Hazards Models , Retrospective Studies , Risk Factors , Taiwan/epidemiology
7.
ACS Appl Mater Interfaces ; 9(46): 40645-40654, 2017 Nov 22.
Article in English | MEDLINE | ID: mdl-29099171

ABSTRACT

We report a versatile strategy to exploit parafilm waste as a carbon precursor for fabrication of freestanding, hollow few-layer graphene fiber mesh (HFGM) structures without use of any gaseous carriers/promoters via an annealing route. The freestanding HFGMs possess good mechanical flexibility, tailorable transparency, and high electrical conductivity, consequently qualifying them as promising electrochemical electrodes. Because of the hollow spaces, electrolyte ions can easily access into and contact with interior surfaces of the graphene fibers, accordingly increasing electrode/electrolyte interfacial area. As expected, solid-state supercapacitors based on the HFGMs exhibit a considerable enhancement in specific capacitance (20-30 fold) as compared to those employing chemical vapor deposition compact graphene films. Moreover, the parafilm waste is found to be beneficial for one-step fabrication of nanocarbon/few-layer graphene composite meshes with superior electrochemical performance, outstanding superhydrophobic property, good self-cleaning ability, and great promise for oil spill cleanup.

8.
J Affect Disord ; 202: 178-86, 2016 Sep 15.
Article in English | MEDLINE | ID: mdl-27262640

ABSTRACT

BACKGROUND: Diabetes and anxiety disorders are independent risk factors for stroke. However, it remains unclear whether the risk of stroke is higher among diabetic patients with comorbid anxiety than without comorbid anxiety. Therefore, the purpose of this study was to investigate the association between comorbid anxiety and the risk of stroke among patients with diabetes. METHODS: This is a retrospective cohort study. We used the National Health Insurance Research Database in Taiwan to identify a diabetes cohort with a new diagnosis of an anxiety disorder but without a history of stroke. The enrollment period was 2001-2006 with up to 11 years of follow-up data. Comorbid anxiety was defined by both a clinical diagnosis of the DSM-IV (ICD-9-CM) and prescriptions for anxiolytic medications. Propensity score matching was performed to balance the selected confounders between the anxiety-exposed group and anxiety non-exposed group. Cox-propositional hazard regression models were used to evaluate the association between comorbid anxiety and the risk of stroke. RESULTS: Among patients with diabetes (N=40,846), an estimated 5.8% (N=2374) of patients had comorbid anxiety disorders. Diabetic patients with comorbid anxiety were significantly associated with a higher risk of stroke compared to patients without comorbid anxiety (hazard ratio: 1.33, 95% confidence interval: 1.02-1.72). LIMITATIONS: The severity of anxiety or diabetes could not be measured from the claims data. Residual confounding may still exist. CONCLUSION: A significantly elevated risk of stroke was observed in association with comorbid anxiety among patients with diabetes. Psychiatrists should consider routine screening for anxiety disorders to prevent a stroke event among patients with diabetes.


Subject(s)
Anxiety Disorders/epidemiology , Diabetes Mellitus, Type 2/epidemiology , Stroke/epidemiology , Aged , Cohort Studies , Comorbidity , Databases, Factual , Diagnostic and Statistical Manual of Mental Disorders , Female , Humans , Male , Middle Aged , Propensity Score , Proportional Hazards Models , Retrospective Studies , Risk Factors , Taiwan
9.
Article in English | MEDLINE | ID: mdl-25574184

ABSTRACT

Background. In 1990s, complementary and alternative medicine (CAM), including use of herbs and supplements, gained popularity in the United States. However, more recent surveys suggest that demand for herbs and supplements has stabilized. Objective. This study examined the prevalence, patterns, and changes in herb and supplement use among the US adults, using the 2002, 2007, and 2012 National Health Interview Surveys (NHIS). Methods. Weighted population estimates were derived from three complementary and alternative medicine supplements to the NHIS. Prevalence rates for herb and supplement use were compared, using Wald chi-square tests to measure changes between years. Results. An estimated 40.6 million US adults reported herb and supplement use in 2012. However, the rate of herb and supplement use dropped from 18.9% in 2002 to 17.9% in 2007 and 2012 (P < 0.05). This decline in use was more pronounced among women, racial or ethnic minorities, and adults with low incomes. Conclusion. Herb and supplements use remains common in the USA, but adult use rates are on the decline. It is still important for health care providers to ask patients about herb and supplement use.

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