Publications by authors named "Su-Yuan Chang"

Background/purpose: To investigate the characteristics of dysosmia and dysgeusia among patients diagnosed with coronavirus disease 2019 (COVID-19) in Taiwan.

Methods: Prospective data collection between January 22, 2020 to May 7, 2020 of nucleic acid confirmed COVID-19 hospitalized patients in northern Taiwan by the Taiwan Centers for Disease Control were analyzed.

Results: Of 217 patients enrolled, 78 (35.

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This study demonstrates the use of positive matrix factorization (PMF) in a region with a major Petrochemical Complex, a prominent source of volatile organic compounds (VOCs), as a showcase of PMF applications. The PMF analysis fully exploited the quality and quantity of the observation data, sufficed by a cluster of 9 monitoring sites within a 20 km radius of the petro-complex. Each site provided continuous data of 54 speciated VOCs and meteorological variables.

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This study investigated the feasibility of analyzing a full range of ambient volatile organic compounds (VOCs) from C(3) to C(12) using gas chromatograph mass spectrometry (GC/MS) coupled with thermal desorption. Two columns were used: a PLOT column separated compounds lighter than C(6) and a DB-1 column separated C(6)-C(12) compounds. An innovative heart-cut technique based on the Deans switch was configured to combine the two column outflows at the ends of the columns before entering the MS.

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This study investigated the sorption/desorption properties of MCM-48 and its applicability as a sorbent for on-line gas chromatographic analysis of ambient volatile organic compounds (VOCs). To establish a valid comparison, commercially available carbon sorbents were evaluated under similar analytical conditions. Two trapping temperatures of 30 degrees C and -20 degrees C, representing ambient and sub-ambient temperatures, were tested by trapping a full range of VOCs from C(2)-C(12).

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An automated sampling and enrichment apparatus coupled with a gas chromatography/mass spectrometry (GC/MS) technique was constructed for the analysis of ambient volatile organic compounds (VOCs). A sorbent trap was built within the system to perform on-line enrichment and thermal desorption of VOCs onto GC/MS. In order to improve analytical precision, calibration accuracy, and to safe-guard the long-term stability of this system, a mechanism to allow on-line internal standard (I.

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Objective: To determine uptake and socio-demographics predictors of acceptance of voluntary counseling and testing (VCT) among post-partum women in Botswana.

Methods: Women attending maternal and child health clinics for their first post-partum or well baby visit in three sites in Botswana were offered VCT after a written informed consent. A standardized questionnaire was used to collect socio-demographic characteristics and reasons for declining VCT.

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Maternal plasma human immunodeficiency virus (HIV) type 1 RNA load has a role in perinatal transmission, but significant overlap in the range of plasma virus loads among transmitters and nontransmitters is often observed, which makes it difficult to predict transmission outcome. We measured several virus markers in a drug-naive population of HIV-1-infected mothers in Botswana. Maternal plasma HIV-1 RNA load, peripheral blood mononuclear cell-associated blood HIV-1 DNA load, and cervicovaginal fluid (CVF) HIV-1 DNA load were determined using quantitative real-time polymerase chain reaction.

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