Browsing by Author "Liu, Ying"

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    Average Weighted Accuracy: Pragmatic Analysis for a Rapid Diagnostics in Categorizing Acute Lung Infections (RADICAL) Study.
    (Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2020-06) Liu, Ying; Tsalik, Ephraim L; Jiang, Yunyun; Ko, Emily R; Woods, Christopher W; Henao, Ricardo; Evans, Scott R
    Patient management relies on diagnostic information to identify appropriate treatment. Standard evaluations of diagnostic tests consist of estimating sensitivity, specificity, positive/negative predictive values, likelihood ratios, and accuracy. Although useful, these metrics do not convey the tests' clinical value, which is critical to informing decision-making. Full appreciation of the clinical impact of a diagnostic test requires analyses that integrate sensitivity and specificity, account for the disease prevalence within the population of test application, and account for the relative importance of specificity vs sensitivity by considering the clinical implications of false-positive and false-negative results. We developed average weighted accuracy (AWA), representing a pragmatic metric of diagnostic yield or global utility of a diagnostic test. AWA can be used to compare test alternatives, even across different studies. We apply the AWA methodology to evaluate a new diagnostic test developed in the Rapid Diagnostics in Categorizing Acute Lung Infections (RADICAL) study.
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    Maternal stress, preterm birth, and DNA methylation at imprint regulatory sequences in humans.
    (Genetics & epigenetics, 2014-01) Vidal, Adriana C; Benjamin Neelon, Sara E; Liu, Ying; Tuli, Abbas M; Fuemmeler, Bernard F; Hoyo, Cathrine; Murtha, Amy P; Huang, Zhiqing; Schildkraut, Joellen; Overcash, Francine; Kurtzberg, Joanne; Jirtle, Randy L; Iversen, Edwin S; Murphy, Susan K
    In infants exposed to maternal stress in utero, phenotypic plasticity through epigenetic events may mechanistically explain increased risk of preterm birth (PTB), which confers increased risk for neurodevelopmental disorders, cardiovascular disease, and cancers in adulthood. We examined associations between prenatal maternal stress and PTB, evaluating the role of DNA methylation at imprint regulatory regions. We enrolled women from prenatal clinics in Durham, NC. Stress was measured in 537 women at 12 weeks of gestation using the Perceived Stress Scale. DNA methylation at differentially methylated regions (DMRs) associated with H19, IGF2, MEG3, MEST, SGCE/PEG10, PEG3, NNAT, and PLAGL1 was measured from peripheral and cord blood using bisulfite pyrosequencing in a sub-sample of 79 mother-infant pairs. We examined associations between PTB and stress and evaluated differences in DNA methylation at each DMR by stress. Maternal stress was not associated with PTB (OR = 0.98; 95% CI, 0.40-2.40; P = 0.96), after adjustment for maternal body mass index (BMI), income, and raised blood pressure. However, elevated stress was associated with higher infant DNA methylation at the MEST DMR (2.8% difference, P < 0.01) after adjusting for PTB. Maternal stress may be associated with epigenetic changes at MEST, a gene relevant to maternal care and obesity. Reduced prenatal stress may support the epigenomic profile of a healthy infant.
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    Sustainable Supply Chain Management for Matthews International
    (2024-04-24) Liu, Ying; Kry, Sokna; Zu, Sebrina
    Matthews International recently updated its environmental sustainability commitments, which encompass ten core pledges. This project aims to enhance sustainable procurement practices at the Industrial Technology Business Unit at Matthews. The focal point of our project is the development of an effective process that guarantees suppliers' compliance with sustainable procurement requirements such as CSRD, CBAM, and EcoVadis. By conducting a gap analysis of Matthews' current scoring and a case study of the supply chain process and the impact of one main raw material, lithium, we found that Matthews' procurement practices still has a lot of room for improvement, especially in supplier diversity, stakeholder engagement, and the integration of environmental and social criteria into its supply chain process. As a result, specific recommendations were proposed for each reporting requirement for a more sustainable procurement process.