三井化学

Automated reaction path network exploration and product identification through kinetic analysis are essential for mimicking real reaction vessels. A common practice involves using inexpensive semiempirical methods for initial exploration, followed by energy refinement using more accurate density functional theory (DFT) methods. However, semiempirical methods often yield less accurate reaction kinetics, making them unsuitable for efficient exploration and reliable product prediction. Here, we demonstrate the advantages of iterative training of a delta-learning neural network potential (ΔNNP) for automated reaction path exploration. Using ethylene polymerization catalyzed by the [ZrCp2CH3]+ catalyst as a model system, we achieve DFT-level accuracy by learning the energy difference between DFT and semiempirical methods. Training the ΔNNP on reaction path networks involving one and two ethylene molecules with the catalyst successfully captures all key elementary steps─initiation, propagation, and termination─which can then be extended to study the polymerization of up to six ethylene molecules. Furthermore, a minimally trained ethylene polymerization model provides a robust foundation for propylene polymerization. We also explore the influence of a cocatalyst on the polymerization elementary step network through additional iterative training. Beyond polymerization, this framework can incorporate other ZrCp2-mediated chemistry, such as metallacycle formation, with minimal additional training─yielding several new metallacycle structures. Overall, this iterative training framework is particularly effective for reactions involving repeated analogous elementary steps, such as polymer growth. The approach enables the model to handle increasingly complex reactions, representing an important step toward realistic mimicking of reaction vessels.

Background While work-family conflict (WFC) has been reported to exert adverse effects on workers' health conditions, evidence linking WFC to presenteeism and absenteeism is not only limited in number but also geographically biased.Aims To examine the associations of WFC with health-related presenteeism and absenteeism among Japanese workers.Methods This study was conducted as part of the Japan Epidemiology Collaboration on Occupational Health study in which we used questionnaire information collected from 7766 workers from five worksites. Absenteeism was defined when they took at least half a day off in the past month. Presenteeism, defined as self-rated poor work performance, was assessed on a scale ranging from 10% to 100%, with those reporting 10-60% classified as poor performance. WFC was assessed using eight items (0-16 scores) with participants categorized into quartiles based on the WFC score. A logistic regression model was used to estimate odds ratios and 95% confidence intervals for presenteeism and absenteeism in relation to WFC categories.Results Of the total participants, 16% reported absenteeism and 15% reported presenteeism. Compared to the individuals in the first quartile of WFC (Q1), individuals in the Q2, Q3 and Q4 categories had 1.17 (0.95-1.43), 1.65 (1.44-1.89) and 2.65 (2.17-3.24) higher odds of absenteeism. The corresponding figures for presenteeism were 1.04 (0.79-1.38), 1.31 (1.13-1.53) and 2.13 (1.85-2.45), respectively.Conclusions Work-family conflict was significantly associated with absenteeism and presenteeism among Japanese workers, which underscores the need to acknowledge and accommodate the balance between work and family responsibilities for workplace health promotion.

IntroductionMaintaining viability and physiological function in kidney tissue slice cultures remains a major challenge for ex vivo renal models, primarily due to limited oxygen diffusion into the tissue interior. In this study, we investigated whether shaking culture could improve the maintenance of primary rat kidney tissue slices.MethodsRat kidney tissue slices (200 µm) were cultured under static or shaking conditions for up to 7 days. Tissue viability, histological features, renal transporter activity, nephrotoxic responses, and metabolomic profiles were evaluated.ResultsShaking culture markedly improved tissue viability, as evidenced by sustained ATP levels over 7 days compared with static conditions. Histological analysis revealed partial preservation of epithelial polarity, indicated by the maintained apical localization of aquaporin 1. Transporter studies demonstrated that uptake activities of Oat1/3 and Oct2 substrates were better preserved under shaking conditions. Furthermore, shaking-cultured slices enabled the evaluation of nephron segment–specific injury, with cisplatin inducing tubular damage and puromycin or dasatinib affecting glomerular structures. Metabolomic analysis revealed distinct alterations in central carbon metabolism, including increased levels of tricarboxylic acid cycle intermediates, suggesting improved mitochondrial function.ConclusionThese findings demonstrate that shaking culture provides a simple and effective approach to improve the culture microenvironment, thereby improving the maintenance of viability and physiological function in kidney tissue slices. This system may serve as a useful platform for investigating renal pharmacokinetics and drug-induced kidney injury.

Adult height may reflect early-life environmental conditions that influence the risk of type 2 diabetes mellitus (DM). While taller height has been linked to lower DM risk, evidence from East Asia remains limited and inconsistent. Given that DM in East Asians often occurs at lower BMI levels, population-specific research is needed. We examined the prospective association between adult height and incident DM in a large Japanese working population, focusing on differences by sex and birth cohort. Data were obtained from annual health checkups of 63,264 workers from 12 companies in Japan, comprising 54,188 men and 9076 women aged 20–64 years at baseline. Participants were classified by quartile of adult height for each sex. DM was defined as either when the participants had glycated hemoglobin (HbA1c) ≥ 6.5