Biomedical subjects

Yujing Shen

Publications and source records attributed to Yujing Shen.

6 recordsLinked to original sources

PubMed2026

Microplastic aging drives convergence of the plastisphere microbiome and resistome toward agricultural soils.

The degree of microplastic (MP) aging varies substantially in agricultural soils; however, how this common aging gradient influences the plastisphere microbiome and resistome remains largely unknown. We therefore collected polyethylene MPs from long‑term mulched farmlands and classified them into low‑aged plastispheres (LAPs) and high‑aged plastispheres (HAPs). Bacterial community dissimilarity to soil decreased progressively from LAPs to HAPs, accompanied by broadening niche breadth, increasing bacterial diversity, and a shift toward more stochastic community assembly. The diversity and abundance of antibiotic resistance genes (ARGs) declined significantly along the aging gradient, with clinically relevant high-risk ARGs (e.g., vanR, ugd, and aac(6')-I) decreasing by 53.34-84.01%. Furthermore, the ARG hosts shifted from Actinomycetota in LAPs to Pseudomonadota in soils. Variance partitioning showed that the carbonyl index uniquely explained 57.03% of the variation in plastisphere ARG profile distance toward soil, identifying MP aging as the primary driver of resistome convergence. Collectively, these findings demonstrate that natural MP aging drives a progressive convergence of the plastisphere resistome toward that of the surrounding soil, indicating that aged MPs may pose a reduced risk of antibiotic resistance compared to newly formed MPs. This convergence underscores the need to incorporate plastic aging into future risk assessment frameworks for plastisphere-associated ARGs.

Soil Microbiology↗

PubMed2003

Applying the 3M All Patient Refined Diagnosis Related Groups Grouper to measure inpatient severity in the VA.

OBJECTIVES: To assess the severity level of acute inpatient care in the Veterans Health Administration (VA) using the 3M All Patient Refined Diagnosis Related Groups (APR-DRGs) Grouper and compare severity levels in the six study sites with other Veterans Affairs Medical Centers. METHODS: Acute inpatient stays were generated based on bedsection movement information in VA Inpatient Medical SAS data sets from federal fiscal years 1997 and 1998. All nonacute bedsections were excluded. The APR-DRG Grouper generated APR-DRG and severity level for each acute inpatient stay using relevant VA data in a fixed format. Severity and length of stay (LOS) within each major APR-DRG (those accounting for at least 0.5% of all acute inpatient stays or days) were compared between study sites and other centers using z scores. RESULTS: Of 315 APR-DRGs, 63 major groups accounted for more than two thirds of all stays and days of care in both years. The study sites were similar in average patient severity and LOS to other centers for most APR-DRGs. For those with significant differences, the six centers had shorter LOS and higher severity. The magnitude of differences was large in LOS and small in severity. CONCLUSIONS: The study sites are generally representative of the overall VA acute inpatient stays. Some adjustments were needed to reflect that the six sites had relatively sicker patients and lower LOS in some of APR-DRGs when resource utilization estimations in the six sites were generalized to the entire VA system. The severity measure of the 3M APR-DRG Grouper can be adapted to the VA controlling for the complicated nature of VA inpatient care.

Diagnosis-Related Groups↗

PubMed2003

Selection incentives in a performance-based contracting system.

OBJECTIVE: To investigate whether a performance-based contracting (PBC) system provides incentives for nonprofit providers of substance abuse treatment to select less severe clients into treatment. DATA SOURCES: The Maine Addiction Treatment System (MATS) standardized admission and discharge data provided by the Maine Office of Substance Abuse (OSA) for fiscal years 1991-1995, provides demographic, substance abuse, and social functional information on clients of programs receiving public funding. STUDY DESIGN: We focused on OSA clients (i.e., those patients whose treatment cost was covered by the funding from OSA) and Medicaid clients in outpatient programs. Clients were identified as being "most severe" or not. We compared the likelihood for OSA clients to be "most severe" before PBC and after PBC using Medicaid clients as the control. Multivariate regression analysis was employed to predict the marginal effect of PBC on the probability of OSA clients being most severe after controlling for other factors. PRINCIPAL FINDINGS: The percentage of OSA outpatient clients classified as most severe users dropped by 7 percent (p < = 0.001) after the innovation of performance-based contracting compared to the increase of 2 percent for Medicaid clients. The regression results also showed that PBC had a significantly negative marginal effect on the probability of OSA clients being most severe. CONCLUSIONS: Performance-based contracting gave providers of substance abuse treatment financial incentives to treat less severe OSA clients in order to improve their performance outcomes. Fewer OSA clients with the greatest severity were treated in outpatient programs with the implementation of PBC. These results suggest that regulators, or payers, should evaluate programs comprehensively taking this type of selection behavior into consideration.

Adult↗

PubMed2003

VHA enrollees' health care coverage and use of care.

The authors examined health care coverage for Veterans' Health Administration (VHA) enrollees and how their reliance on VHA care varies by coverage, using the largest and most detailed survey of veterans using VHA services ever conducted. The results showed that a majority of veterans who use VHA services have alternative health care coverage and that most of them use both VHA and non-VHA health care. The findings have important implications for quality of care and coordination of care.

Aged↗

PubMed2002

How profitable is risk selection? A comparison of four risk adjustment models.

To mitigate selection triggered by capitation payments, risk-adjustment models bring capitation payments closer on average to individuals' expected expenditure. We examine the maximum potential profit that plans could hypothetically gain by using their own private information to select low-cost enrollees when payments are made using four commonly used risk adjustment models. Simulations using a privately insured sample suggest that risk selection profits remain substantial. The magnitude of potential profit varies according to the risk adjustment model and the private information plans can employ to identify profitable enrollees.

Actuarial Analysis↗

PubMed2002

Cost-minimizing risk adjustment.

Conventional risk adjustment, which sets capitation payments equal to the average cost of individuals with similar observable characteristics, is not optimal if health plans can use private information to select low-cost enrollees. "Cost-minimizing risk adjustment" minimizes the sum of capitated HMO premiums plus FFS costs by balancing the gains from HMO cost efficiency against the overpayments that result from HMO selection. Estimations using privately-insured data suggest that cost-minimizing risk adjusted premiums reduce total sponsor costs as much as 25.6% below conventional risk adjustment premiums.

Actuarial Analysis↗