Publications by authors named "Chieh-An Cheng"

The widespread use of alcohol-based hand sanitizers (ABHS) during and after the COVID-19 pandemic has raised concerns about potential exposure to harmful volatile organic compounds (VOCs), such as benzene, acetaldehyde, and other impurities, which may pose health risks. This study investigated the concentrations of ethanol, isopropanol, and 12 impurities, including benzene, acetaldehyde, and methanol, in 85 commercially available ABHS products in Taiwan using gas chromatography-mass spectrometry (GC-MS). The results revealed that 12 samples contained alcohol concentrations below the recommended 60% (/) threshold.

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Ammonia is an environmental pollutant that is toxic to all aquatic animals. However, the mechanism of ammonia toxicity toward the ion regulatory function of early-stage fish has not been fully documented. We addressed this issue using zebrafish embryos as a model.

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Ammonia pollutants were usually found in aquatic environments is due to urban sewage, industrial wastewater discharge, and agricultural runoff and concentrations as high as 180 mg/L (NH) have been reported in rivers. High ammonia levels are known to impair multiple tissue and cell functions and cause fish death. Although ammonia is a potent neurotoxin, how sublethal concentrations of ammonia influence the central nervous system (CNS) and the complex behaviors of fish is still unclear.

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Article Synopsis
  • A study conducted at a medical university aimed to measure indoor concentrations of five volatile organic compounds (VOCs) commonly used in experiments, focusing on health risks for faculty and students.
  • Air samples were collected from 10 locations across campus during different seasons, revealing that dichloromethane had the highest detection level, particularly in the Department of Medicine.
  • The results indicated possible carcinogenic risks from benzene and dichloromethane for faculty, while noncarcinogenic risks were mostly low, except for dichloromethane, which exceeded safe levels, suggesting a need for improved ventilation and reduced usage.
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Article Synopsis
  • Negative differential resistance (NDR) devices show promise in applications like switches and memory due to their unique characteristics.
  • Researchers synthesized graphene oxide quantum dots (GOQDs) which demonstrated notable NDR properties at room temperature, achieving a peak-to-valley ratio of 4.7 when voltage was varied from -6 to 6 V.
  • The NDR can be modulated by adjusting factors such as applied voltage range, air pressure, humidity, and H2O2 concentration during synthesis, indicating a connection between GOQD aggregation and charge carrier behavior.
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