Rashba-Dresselhaus spin-orbit coupling and polarization-coupled luminescence in an organic single crystal microcavity

Spin-orbit coupling (SOC) of light plays a fundamental photophysics that is important for various fields such as materials science, optics, and quantum technology, contributing to the elucidation of new physical phenomena and the development of innovative applications. In this study, we investigate the impact of SOC in a microcavity system using the highly oriented molecular crystal. The unique molecular alignment of our crystal creates substantial optical anisotropy, enabling the observation of significant SOC effects within a microcavity form. Through angle-resolved photoluminescence measurements and theoretical calculations, the presence of Rashba-Dresselhaus (RD) SOC in the lower branch of polariton modes is revealed. We have observed for the first time polarization-coupled emission from polariton modes due to the RD-SOC effect in a microcavity with a medium having both strong light-matter coupling and strong optical anisotropy. Theoretical investigations further elucidate the intricate interplay between the RD-SOC effect and anisotropic light-matter coupling, leading to the emergence of both circularly and diagonally polarized mode splittings. This study not only advances our understanding of optical SOC in microcavities but also highlights the potential of highly oriented molecular crystals in manipulating SOC effects without external electric or magnetic fields. These findings offer greatly promising platforms for developing topological photonics and quantum technologies

Long-term outcomes after definitive repair for tetralogy of Fallot with preservation of the pulmonary valve annulus

ObjectivesThe aim of our study was to evaluate the long-term outcomes after definitive repair of tetralogy of Fallot with preservation of the pulmonary valve (PV) annulus.MethodsFrom 1989 to 2000, 84 of 222 patients (37.8%) with tetralogy of Fallot and PV stenosis underwent definitive repair with preservation of the PV annulus without right ventriculotomy. PV commissurotomy was concomitantly performed in 74 patients (88.1%). The PV was bicuspid in 56 patients (66.7%); the mean Z value was −1.2 ± 1.5 (range, −4.9 to 2.4). The mean follow-up period was 15.8 ± 5.7 years (maximum, 22.8), and follow-up data were complete for 75 patients (89.3%).ResultsThe actuarial survival and freedom from reoperation rates at 20 years was 98.6% and 95.8%. The freedom from ventricular arrhythmia at 5, 10, 15, and 20 years was 98.7%, 89.6%, 74.1%, and 58.0%, respectively. All detected ventricular arrhythmias were isolated monofocal premature ventricular contractions. Freedom from moderate or greater pulmonary regurgitation at 5, 10, 15 and 20 years was 50.4%, 44.9%, 38.4%, and 35.7%, respectively. A bicuspid PV (hazard ratio, 2.910; 95% confidence interval, 1.404-6.204, P = .004) and a Z-value of less than −2 (hazard ratio, 1.948; 95% confidence interval, 0.915-5.857; P = .034) were the risk factors for developing moderate or greater pulmonary regurgitation.ConclusionsThe long-term outcomes after definitive repair of tetralogy of Fallot with preservation of the PV annulus were excellent. Although isolated, monofocal premature ventricular contractions were frequently observed, fatal ventricular arrhythmia was not. The indication should not only be decided by the PV annulus size, but also by the valvular morphology to maintain long-term PV competency

A case of rhinocerebral mucormycosis with brain abscess drained by endoscopic endonasal skull base surgery

A 70-year-old Japanese man undergoing remission induction therapy for acute monocytic leukemia (AML-M5b) developed fever and headache, and was started on antibiotics and liposomal amphotericin B (L-AMB). There was no improvement, and computed tomography and contrast-enhanced magnetic resonance imaging revealed acute rhinosinusitis and brain abscess. Successful endoscopic endonasal surgery was performed at this point, providing drainage for the rhinosinusitis and abscess. Histopathological findings showed the mucormycosis

Predictors of Survival in Patients With Ischemic Stroke and Active Cancer: A Prospective, Multicenter, Observational Study

BACKGROUND: Limited data exist on the prognostic factors for patients with ischemic stroke and active cancer. METHODS AND RESULTS: We conducted a prospective, multicenter, observational study in Japan, including patients with acute ischemic stroke and active cancer, to investigate the prognostic factors. We followed up the patients for 1 year after stroke onset. The patients were divided into 2 groups according to cryptogenic stroke and known causes (small-vessel occlusion, large-artery atherosclerosis, cardioembolism, and other determined cause), and survival was compared. The hazard ratios (HRs) and 95% CIs for mortality were calculated using Cox regression models. We identified 135 eligible patients (39% women; median age, 75 years). Of these patients, 51% had distant metastasis. A total of 65 (48%) and 70 (52%) patients had cryptogenic stroke and known causes, respectively. Patients with cryptogenic stroke had significantly shorter survival than those with known causes (HR [95% CI], 3.11 [1.82–5.32]). The multivariable Cox regression analysis revealed that distant metastasis, plasma D-dimer levels, venous thromboembolism (either deep venous thrombosis or pulmonary embolism) complications at stroke onset were independent predictors of mortality after adjusting for potential confounders. Cryptogenic stroke was associated with prognosis in univariable analysis but was not significant in multivariable analysis. The plasma D-dimer levels stratified the prognosis of patients with ischemic stroke and active cancer. CONCLUSIONS: The prognosis of patients with acute ischemic stroke and active cancer varied considerably depending on stroke mechanism, distant metastasis, and coagulation abnormalities. The present study confirmed that coagulation abnormalities were crucial in determining the prognosis of such patients.Gon Y., Sakaguchi M., Yamagami H., et al. Predictors of Survival in Patients With Ischemic Stroke and Active Cancer: A Prospective, Multicenter, Observational Study. Journal of the American Heart Association 12, e029618 (2023); https://doi.org/10.1161/JAHA.123.029618

Novel function of HATs and HDACs in homologous recombination through acetylation of human RAD52 at double-strand break sites

The p300 and CBP histone acetyltransferases are recruited to DNA double-strand break (DSB) sites where they induce histone acetylation, thereby influencing the chromatin structure and DNA repair process. Whether p300/CBP at DSB sites also acetylate non-histone proteins, and how their acetylation affects DSB repair, remain unknown. Here we show that p300/CBP acetylate RAD52, a human homologous recombination (HR) DNA repair protein, at DSB sites. Using in vitro acetylated RAD52, we identified 13 potential acetylation sites in RAD52 by a mass spectrometry analysis. An immunofluorescence microscopy analysis revealed that RAD52 acetylation at DSBs sites is counteracted by SIRT2- and SIRT3-mediated deacetylation, and that non-acetylated RAD52 initially accumulates at DSB sites, but dissociates prematurely from them. In the absence of RAD52 acetylation, RAD51, which plays a central role in HR, also dissociates prematurely from DSB sites, and hence HR is impaired. Furthermore, inhibition of ataxia telangiectasia mutated (ATM) protein by siRNA or inhibitor treatment demonstrated that the acetylation of RAD52 at DSB sites is dependent on the ATM protein kinase activity, through the formation of RAD52, p300/CBP, SIRT2, and SIRT3 foci at DSB sites. Our findings clarify the importance of RAD52 acetylation in HR and its underlying mechanism

Porous Plug Phase Separator and Superfluid Film Flow Suppression System for the Soft X-Ray Spectrometer Onboard Hitomi

When using superfluid helium in low gravity environments, porous plug phase separators are commonly used to vent boiloff gas while confining the bulk liquid to the tank. Invariably, there is a flow of superfluid film from the perimeter of the porous plug down the vent line. For the Soft X-ray Spectrometer onboard ASTRO-H (Hitomi), its approximately 30-liter helium supply has a lifetime requirement of more than 3 years. A nominal vent rate is estimated as ~ 30 ug/s, equivalent to ~ 0.7 mW heat load. It is therefore critical to suppress any film flow whose evaporation would not provide direct cooling of the remaining liquid helium. That is, the porous plug vent system must be designed to both minimize film flow and to ensure maximum extraction of latent heat from the film. The design goal for Hitomi is to reduce the film flow losses to <2 ug/s, corresponding to a loss of cooling capacity of <40 uW. The design adopts the same general design as implemented for Astro-E and E2, using a vent system composed of a porous plug, combined with an orifice, a heat exchanger, and knife-edge devices. In this paper, design, on-ground testing results and in-orbit performance are described

Cooling system for the soft X-ray spectrometer onboard Astro-H

金沢大学理工研究域数物科学系The Soft X-ray Spectrometer (SXS) is a cryogenic high resolution X-ray spectrometer onboard the X-ray astronomy satellite Astro-H which will be launched in 2014. The detector array is cooled down to 50 mK using an adiabatic demagnetization refrigerator (ADR). The cooling chain from the room temperature to the ADR heat-sink is composed of superfluid liquid He, a Joule-Thomson cryocooler, and double-stage Stirling cryocoolers. It is designed to keep 30 l of liquid He for more than 5 years in the normal case, and longer than 3 years even if one of the cryocoolers fails. Cryogen-free operation is also possible in the normal case. It is fully redundant from the room temperature to the ADR heat-sink. © 2010 Elsevier Ltd