Spatio-temporal chaos of one-dimensional thin elastic layer with the rate-and-state friction law

The rate-and-state friction (RSF) law is an empirical law often used to model the behavior of rock friction and reproduce the behavior of earthquakes. Recently, the model has been expanded to include so-called slow earthquakes, which are observed at the margins between steadily sliding aseismic and seismogenic zones. In this study, we incorporate the RSF law into a one-dimensional elastic layer spanned perpendicular to the loading direction as a model for the marginal area between aseismic and seismogenic zones. We obtained the complex Ginzburg-Landau equation near a Hopf bifurcation, and showed that the system has Benjamin-Fair instability, leading to spatio-temporal chaos. We conducted numerical calculations near the Hopf bifurcation point, and showed that an irregular oscillation appears when parameters with Benjamin-Feir instability are employed. The size of slip event showed an exponential distribution that resembles a type of slow earthquake.Comment: 33 pages, 7 figure

Theory of Josephson current on a lattice model of grain boundary in dd-wave superconductors

Identifying the origins of suppression of the critical current at grain boundaries of high-critical-temperature superconductors, such as cuprates and iron-based superconductors, is a crucial issue to be solved for future applications with polycrystalline materials. Although the dominant factor of current suppression might arise during material fabrication and/or processing, investigating it due to an internal phase change of the pair potential is an important issue in understanding the threshold of the critical current. In this paper, we study the Josephson current on a symmetric [001]-tilt grain boundary (GB) of a $d$-wave superconductor on a lattice model. In addition to the suppression of the maximum Josephson current associated with the internal phase change of the $d$-wave pair potential which has been predicted in continuum models, we find a unique phase interference effect due to folding of the Fermi surface in the lattice model. In particular, the resultant maximum Josephson current at low-tilting-angle regions tends to be suppressed more than that in preexisting theories. Because similar suppressions of the critical current at GBs have been reported in several experimental works, the present model can serve as a guide to clarify the complicated transport mechanism in GBs

Transplantation of genetically marked cardiac muscle cells

AbstractWe examined the possibility that cardiomyocytes could be genetically marked or modified before being grafted to the heart under conditions applicable to the clinical setting. We used a replication-defective recombinant adenovirus carrying the β-galactosidase reporter gene, and delivered it to cultured murine fetal cardiac myocytes. Virtually all fetal cardiomyocytes in a primary culture expressed β-galactosidase 24 hours after recombinant adenovirus infection. These cells were transplanted to the hearts of syngenic adult recipient mice. Expression of the β-galactosidase gene in the grafted cells was demonstrated by staining with 5-bromo-4-chloro-3-indoyl-β-d-galactosidase, resulting in a blue color at the histochemical level and an electron-dense deposit on transmission electron microscopic analysis. Gene expression was recognized from 7 days to 12 weeks after transplantation. Implanted cardiomyocytes aligned themselves along the layers of the host myocardium. Formation of gap junctions was demonstrated by transmission electron microscopy. Neither inflammation nor fibrous scar tissue was detectable by histologic analysis. This study demonstrates that ex vivo gene transfer to the heart by means of the adenoviral vector is possible. (J Thorac Cardiovasc Surg 1997;113:10-8

Validation of the Japanese version of the revised version of the compound psychological capital scale (CPC-12R)

This study developed a Japanese version of the Revised Version of the Compound Psychological Capital Scale (CPC-12R) and tested its reliability and construct validity. The participants were 1,000 young adults (500 university students and 500 employees) recruited through an internet survey. Confirmatory factor analysis showed that the four first-order factors (hope, optimism, resilience, and self-efficacy) and one second-order factor (PsyCap) model of the previous study is appropriate for the Japanese context. In addition, Cronbach’s α and omega-higher-order of CPC-12R were sufficient. The measurement invariance analysis suggested sufficient scalar invariances for the employees and university students and across genders. The Japanese version of the CPC-12R had moderate positive correlations with job satisfaction, work engagement, conscientiousness, and extraversion, as well as a moderate negative correlation with negative emotionality. These findings provide evidence for sufficient reliability and construct validity of the Japanese version of the CPC-12R

The usefulness of preoperative bile cultures for hepatectomy with biliary reconstruction

[Background] Infectious complications can cause lethal liver failure after hepatectomy with biliary reconstruction. This study assessed the increased risk for postoperative infectious complications in patients who underwent hepatectomy with biliary reconstruction and explored the possibility of predicting pathogenic microorganisms causing postoperative infectious complications based on preoperative monitoring of bile cultures. [Methods] This study involved 310 patients who received major hepatectomy with or without biliary reconstruction at our institution between January 2010 and December 2019. The relationship between the microorganisms detected through perioperative monitoring of bile culture and those in the postoperative infectious foci was examined. [Results] Forty-nine patients underwent major hepatectomy with biliary reconstruction, and 261 received hepatectomy without biliary reconstruction. The multivariate analysis revealed hepatectomy with biliary reconstruction to be associated with an increased risk of postoperative infectious complications (odds ratio: 22.9, 95% confidence interval: 5.2–164.3) compared to hepatectomy without biliary reconstruction. In the patients with biliary reconstruction, the concordance rates between the microorganisms detected in the postoperative infectious foci and those in preoperative bile cultures were as follows: incisional surgical site infection (44.4%), organ/space surgical site infection (52.9%), bacteremia (47.1%), and pneumonia (16.7%); the concordance rates were high, and the risk of infection increased over time. [Conclusions] Biliary reconstruction is a significant risk factor for postoperative infectious complications, and preoperative bile cultures may aid in prophylactic and therapeutic antimicrobial agent selection