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Jinyu Chen

Publications and source records attributed to Jinyu Chen.

38 records · Page 3Linked to original sources

Effective Metagraph-based Life Pattern Clustering with Big Human Mobility Data

Life pattern clustering is essential for abstracting the groups' characteristics of daily mobility patterns and activity regularity. Based on millions of GPS records, this paper proposed a framework on the life pattern clustering which can efficiently identify the groups have similar life pattern. The proposed method can retain original features of individual life pattern data without aggregation. Metagraph-based data structure is proposed for presenting the diverse life pattern. Spatial-temporal similarity includes significant places semantics, time sequential properties and frequency are integrated into this data structure, which captures the uncertainty of an individual and the diversities between individuals. Non-negative-factorization-based method was utilized for reducing the dimension. The results show that our proposed method can effectively identify the groups have similar life pattern and takes advantages in computation efficiency and robustness comparing with the traditional method. We revealed the representative life pattern groups and analyzed the group characteristics of human life patterns during different periods and different regions. We believe our work will help in future infrastructure planning, services improvement and policies making related to urban and transportation, thus promoting a humanized and sustainable city.

cs.CY↗

Population pharmacokinetics and dosing regimen optimization of tacrolimus in Chinese lung transplant recipients

We aimed to develop a population pharmacokinetic model of tacrolimus in Chinese lung transplant recipients, and propose model based dosing regimens for individualized treatment. We obtained 807 tacrolimus whole blood concentrations from 52 lung transplant patients and genotyped CYP3A5*3. Population pharmacokinetic analysis was performed using nonlinear mixed effects modeling. Monte Carlo simulations were employed to design initial dosing regimens. Tacrolimus pharmacokinetics was described by a one compartment model with first order absorption and elimination process. The mean estimated apparent clearance was 13.1 l/h with 20.1% inter subject variability in CYP3A5*3/*3 70kg patients with 30% hematocrit and voriconazole free therapy, which is lower than that in Caucasian(17.5 to 36.5 l/h). Hematocrit, postoperative days, tacrolimus daily dose, voriconazole cotherapy, and CYP3A5*3 genotype were identified as significant covariates for tacrolimus clearance. To achieve the target trough concentration (10 to 15 ng/ml) on the 8th day after transplantation, CYP3A5*1/*3 patients with voriconazole free cotherapy, a higher initial dosage than the current regimen of 0.04 mg/kg q12h should be recommened. Given the nonlinear kinetics of tacrolimus and large variability, population pharmacokinetic model should be combined with therapeutic drug monitoring to optimize individualized therapy.

q-bio.TO↗