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We reviewed the time-dependent multiconfiguration self-consistent-field (TD-MCSCF) method and the time-dependent optimized coupled-cluster (TD-OCC) method for first-principles simulations of high-field phenomena such as tunneling ionization and high-order harmonic generation in atoms and molecules irradiated by a strong laser field. These methods provide a flexible and systematically improvable description of the multielectron dynamics by expressing the all-electron wavefunction by configuration interaction expansion or coupled-cluster expansion, using time-dependent one-electron orbital functions. The time-dependent variational principle plays a key role in deriving these methods while satisfying gauge invariance and Ehrenfest theorem. The real-time/real-space implementation with an absorbing boundary condition enables the simulation of high-field processes involving multiple excitation and ionization. We present a detailed, comprehensive discussion of such features of the TD-MCSCF and TD-OCC methods. Key words: TD-MCSCF, TD-OCC, high-field phenomena, electron dynamics, 1. Introduction High-field physics (also known as strong field physics) is a field that studies high-field phenomena such as abovethreshold ionization, tunneling ionization, high-order harmonic generation (HHG), and nonsequential double [...]

We present an implementation of the multiconfiguration time-dependent Hartree-Fock method hased on the adaptive finite element method for molecules under intense laser pulses. For efficient simulations, orbital functions are propagated by a stable propagator using the short iterative Arnoldi scheme and our implementation is parallelized for distributed memory computing. This is demonstrated by simulating high-harmonic generation from a water molecule and achieves a simulation of multielectron dynamics with overwhelmingly less computational time, compared to our previous work [Sawada, R. et al. Phys. Rev. A, 2016, 93, 023434]. Key words: Ab initio simulation, multielectron dynamics in molecules, intense laser field, TD-MCSCF method, 1. Introduction Multielectron dynamics studied in strong-field physics and attosecond science is a complicated phenomenon, which includes non-perturbative and nonlinear effects, and multiple states or paths excited by ultrashort pulses. [...]

Rheology plays a pivotal role in understanding the flow behavior of fluids by discovering governing equations that relate deformation and stress, known as constitutive equations. Despite the importance of these equations, current methods for deriving them lack a systematic methodology, often relying on sense of physics and incurring substantial costs. To overcome this problem, we propose a novel method named Rheo-SINDy, which employs the sparse identification of nonlinear dynamics (SINDy) algorithm for discovering constitutive models from rheological data. Rheo-SINDy was applied to five distinct scenarios, four with well-established constitutive equations, and one without predefined equations. Our results demonstrate that Rheo-SINDy successfully identified accurate models for the known constitutive equations and derived physically plausible approximate models for the scenario without established equations. Notably, the identified approximate models can accurately reproduce nonlinear shear rheological properties, especially at steady state, including shear thinning. These findings validate the availability of Rheo-SINDy in handling data complexities and underscore its potential for advancing the development of data-driven approaches in rheology. Nevertheless, further refinement of learning strategies is essential for enhancing robustness to fully account for the complexities of real-world rheological data. [ABSTRACT FROM AUTHOR]

The 2024 Noto Peninsula Earthquake, which struck on January 1 during Japan's holiday season, may have led to some delays in response efforts. It is important to acknowledge that many individuals likely responded promptly, and this statement is not intended to criticize the responses of various parties. Another significant challenge was how regions outside the affected area could effectively support those impacted, especially in terms of school education soon after the disaster. This study provides a preliminary report on a school education support project initiated in response to the earthquake. The primary focus is on the centralized information portal site launched on January 3, designed for "supporting supporters." Additionally, the study covers the rapid response meeting held on January 9 and the report meeting on May 8, both at the International Research Institute of Disaster Science, Tohoku University, Sendai, Japan. These initiatives aim to address and summarize current challenges and outline future directions for schools in Ishikawa Prefecture and across Japan. We hope that this study will contribute to recovery and reconstruction efforts in Ishikawa Prefecture and enhance resilient school education worldwide. [ABSTRACT FROM AUTHOR]

Background: Peroral cholangioscopy (POCS) is valuable for assessing malignant biliary strictures; however, biliary drainage prior to POCS often hinders accurate diagnosis. Objectives: This retrospective study aimed to investigate the feasibility of POCS using a newly developed cholangioscope, CHF-B290, during initial endoscopic retrograde cholangiopancreatography (ERCP) for malignant biliary strictures. Methods: This multicenter retrospective study included patients who underwent initial ERCP for malignant biliary strictures at two institutions between January 2018 and March 2022. Patients who underwent initial ERCP with POCS were classified into the POCS group, and those without POCS were classified into the non-POCS group. To prevent post-POCS cholangitis, the original irrigation system for CHF-B290 was used in all POCS examinations. The primary endpoint was the rate of post-ERCP biliary infections, and the secondary endpoints were other ERCP-related complications, including pancreatitis, bleeding, and perforation. Results: Overall, 53 and 94 patients were included in the POCS and non-POCS groups, respectively. For the primary endpoint, the rate of post-ERCP biliary infection was not significantly different between the two groups (1.9% vs. 5.3%, p = 0.42). For the secondary endpoints, no significant differences were observed in the rates of post-ERCP pancreatitis (5.7% vs. 6.4%, p = 1.00) and other ERCP-related complications. The overall complication rate was 9.4% in the POCS group and 13% in the non-POCS group (p = 0.60). Conclusions: POCS during the initial ERCP for malignant biliary strictures is feasible. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to develop models for predicting total serum bilirubin by correcting errors of transcutaneous bilirubin using machine learning based on neonatal biomarkers that could affect spectrophotometric measurements of tissue bilirubin. Methods: This retrospective study included infants born at our hospital (≥36 weeks old, ≥2,000 g) between January 2020 and December 2022. Infants without a phototherapy history were included. Robust linear regression, gradient boosting tree, and neural networks were used for machine learning models. A neural network, inspired by the structure of the human brain, was designed comprising three layers: input, intermediate, and output. Results: Totally, 683 infants were included. The mean (minimum-maximum) gestational age, birth weight, participant age, total serum bilirubin, and transcutaneous bilirubin were 39.0 (36.0–42.0) weeks, 3,004 (2,004–4,484) g, 2.8 (1–6) days of age, 8.50 (2.67–18.12) mg/dL, and 7.8 (1.1–18.1) mg/dL, respectively. The neural network model had a root mean square error of 1.03 mg/dL and a mean absolute error of 0.80 mg/dL in cross-validation data. These values were 0.37 mg/dL and 0.28 mg/dL, smaller compared to transcutaneous bilirubin, respectively. The 95% limit of agreement between the neural network estimation and total serum bilirubin was −2.01 to 2.01 mg/dL. Unnecessary blood draws could be reduced by up to 78%. Conclusion: Using machine learning with transcutaneous bilirubin, total serum bilirubin estimation error was reduced by 25%. This integration could increase accuracy, lessen infant discomfort, and simplify procedures, offering a smart alternative to blood draws by accurately estimating phototherapy thresholds. Plain Language Summary: Neonatal jaundice is a common condition that might occur in the first week of life. Severe high bilirubin levels can lead to long-term problems like cerebral palsy, hearing impairment, and developmental delay. Therefore, newborns are usually evaluated for jaundice every day during their first week. To accurately assess jaundice, we need to measure the total bilirubin in the blood. However, daily blood draws for bilirubin measurements can be uncomfortable and may cause anemia in newborns. Thus, transcutaneous bilirubinometry is devised. It is a device that measures bilirubin through the skin and is commonly used because it is non-invasive. However, transcutaneous bilirubinometry has some accuracy issues. In this study, we successfully improved the accuracy of bilirubin measurement by combining machine learning with transcutaneous bilirubinometry. Being used alone, the transcutaneous bilirubinometer had an error of 1.08 mg/dL. However, combining transcutaneous bilirubinometry with machine learning, the error decreased to 0.80 mg/dL, which is a 25% of improvement. Using this approach, unnecessary blood draws could be reduced by up to 78%. If we incorporate this algorithm into transcutaneous bilirubinometry, this novel method has the potential to improve prediction accuracy and reduce the burden on babies. [ABSTRACT FROM AUTHOR]

This is the first registered intervention study for vonoprazan, high-dose amoxicillin, clarithromycin, and metronidazole 14-day concomitant therapy based on a susceptibility test of Helicobacter pylori. We conducted this study as a fourth-line rescue regimen in Japan. Methods: Twenty patients who underwent three rounds of eradication therapies (first- or second-line 7-day triple therapy consisting of amoxicillin and clarithromycin, or metronidazole- and sitafloxacin-based third-line therapy) and had failed eradication based on a urea breath test or fecal antigen test were recruited. All patients underwent endoscopic examination and culture tests before starting eradication therapy. The intervention was concomitant therapy consisting of vonoprazan 20 mg bid, amoxicillin 500 mg qid, clarithromycin 400 mg bid, and metronidazole 250 mg bid for 14 days, which were modified based on the susceptibility test, and the resistant drugs were removed from the regimen. Patients with negative culture results were treated with quadruple therapy. The primary outcome was the eradication rate (UMIN000025765, jRCTs 031180208). Results: The eradication rate of susceptibility-testing-based fourth-line eradication therapy was 63.2% (95%CI: 38.4–83.7%) in intent-to-treat analysis and 70.6% (95%CI: 44.0–89.7%) in per-protocol analysis. Thirteen patients received quadruple therapy, with eradication rates of 61.5% and 75.0%, respectively. No serious adverse events were reported. Conclusions: This vonoprazan-based concomitant therapy modified by the susceptibility test is a potential option as fourth-line eradication after first-line clarithromycin-based 7-day triple, second-line metronidazole-based 7-day triple, and third-line sitafloxacin-based 7-day triple therapy failure. [ABSTRACT FROM AUTHOR]

We examined a phase separation process of a dynamically asymmetric blend of unentangled polyisoprene (PI) and poly(4-ethylstyrene) (PC2St) exhibiting the upper critical solution temperature. PI having the type-A dipole was the dielectrically active fast component, whereas PC2St was the dielectrically inert slow component whose dynamics can be detected by rheological measurements. To precisely model the phase separation process, it is important to estimate the composition dependence of the mobility, which is needed to describe the phase separation dynamics. For that purpose, we conducted dielectric and rheological measurements to determine the friction coefficient of each component in a homogeneous state sufficiently above the phase separation temperature. The temperature dependence of the friction coefficient of each component was reasonably expressed by the Williams–Landel–Ferry equation. Extrapolating this dependence obtained for blends of various compositions to the test temperature T* below the phase separation temperature, we were able to estimate the friction coefficient of the chain at T* as a function of the composition. This friction coefficient was then used to determine the mobility Λ defined for the material fluxes at T*. The time-dependent Ginzburg–Landau (TDGL) equation incorporating this Λ well described the experimentally observed phase separation dynamics. In particular, the 2D TDGL simulation with this Λ qualitatively captured the phase-separated structure observed with the optical microscope as well as broad dielectric mode distribution of the blend at T*. [ABSTRACT FROM AUTHOR]