Evaluation of heat extraction through sapphire fibers for the GW observatory KAGRA

Currently, the Japanese gravitational wave laser interferometer KAGRA is under construction in the Kamioka mine. As one main feature, it will employ sapphire mirrors operated at a temperature of 20K to reduce the impact from thermal noise. To reduce seismic noise, the mirrors will also be suspended from multi-stage pendulums. Thus the heat load deposited in the mirrors by absorption of the circulating laser light as well as heat load from thermal radiation will need to be extracted through the last suspension stage. This stage will consist of four thin sapphire fibers with larger heads necessary to connect the fibers to both the mirror and the upper stage. In this paper, we discuss heat conductivity measurements on different fiber candidates. While all fibers had a diameter of 1.6mm, different surface treatments and approaches to attach the heads were analyzed. Our measurements show that fibers fulfilling the basic KAGRA heat conductivity requirement of $\kappa\geq$5000W/m/K at 20K are technologically feasible.Comment: 11 pages, 4 figure

Genes Encoding the T-Cell Antigen Receptor

The search for the elusive and controversial T-cell antigen receptor is over. It is now clear that gene complexes for both alpha and beta chains are distinct from those for immunoglobulin genes. They are, however, related to Ig genes as well as to other class I and class II major histocompatibility complex (MHC) gene products. Therefore, they belong to the immunoglobulin super gene family

Significance of Exercise-Related Ventricular Arrhythmias in Patients With Brugada Syndrome

Background Sinus tachycardia during exercise attenuates ST‐segment elevation in patients with Brugada syndrome, whereas ST‐segment augmentation after an exercise test is a high‐risk sign. Some patients have premature ventricular contractions (PVCs) related to exercise, but the significance of exercise‐related PVCs in patients with Brugada syndrome is still unknown. The objective of this study was to determine the significance of exercise‐related PVCs for predicting occurrence of ventricular fibrillation (VF) in patients with Brugada syndrome. Methods and Results The subjects were 307 patients with Brugada syndrome who performed a treadmill exercise test. We evaluated the occurrence of PVCs at rest, during exercise and at the peak of exercise, and during recovery after exercise (0–5 minutes). We followed the patients for 92±68 months and evaluated the occurrence of VF. PVCs occurred in 82 patients (27%) at the time of treadmill exercise test: PVCs appeared at rest in 14 patients (4%), during exercise in 60 patients (20%), immediately after exercise (0–1.5 minutes) in 28 patients (9%), early after exercise (1.5–3 minutes) in 18 patients (6%), and late after exercise (3–5 minutes) in 12 patients (4%). Thirty patients experienced VF during follow‐up. Multivariable analysis including symptoms, spontaneous type 1 ECG, and PVCs in the early recovery phase showed that these factors were independently associated with VF events during follow‐up. Conclusions PVCs early after an exercise test are associated with future occurrence of VF events. Rebound of vagal nerve activity at the early recovery phase would promote ST‐segment augmentation and PVCs in high‐risk patients with Brugada syndrome

Suppression of Interferon-induced Oligo-2\u27, 5\u27-adenylate Synthetase Induction in Human Hepatoma Cell Line, Li-7

Induction of oligo-2\u27, 5\u27-adenylate synthetase (2-5AS) activity by interferon (IFN) was investigated in a human hepatoma cell line, Li-7 cells. Little induction of 2-5AS activity by IFN was demonstrated in Li-7 cells in comparison with other types of cell lines including Ramos, NC-37, FL, Co-3. Furthermore, failure to induce 2-5AS was much clearer in old-cultured cells. Cell growth inhibition by IFN was demonstrated in only high titers of IFN (>10? IU/ml), in which the enzyme had one hundred fold higher activity than that of untreated cells. Poor induction of 2-5AS was in part the result of some inhibitor presented in cellular extracts of Li-7 cells and the decreased level of 2-5AS mRNA transcription

X-ray diffractometry for the structure determination of a submicrometre single powder grain

A high-precision diffractometer with a synchrotron radiation microfocusing technique has been developed to investigate the crystal structure of a submicrometre-scale single grain of powder sample. The structure of a BaTiO3 single powder grain, of dimensions ∼600 × 600 × 300 nm, was determined

Preoperative prognostic nutritional index predicts postoperative infectious complications and oncological outcomes after hepatectomy in intrahepatic cholangiocarcinoma

Background: In the surgical treatment of intrahepatic cholangiocarcinoma (ICC), postoperative complications may be predictive of long-term survival. This study aimed to identify an immune-nutritional index (INI) that can be used for preoperative prediction of complications. Patients and methods: Multi-institutional data from 316 patients with ICC who had undergone surgical resection were retrospectively analysed, with a focus on various preoperative INIs. Results: Severe complications (Clavien-Dindo grade III-V) were identified in 66 patients (20.8%), including Grade V complications in 7 patients (2.2%). Comparison of areas under the receiver operating characteristic curve (AUCs) among various INIs identified the prognostic nutritional index (PNI) as offering the highest predictive value for severe complications (AUC = 0.609, cut-off = 50, P = 0.008). Multivariate analysis revealed PNI = 50, n = 142) and a low-PNI group (PNI Conclusion: Preoperative PNI appears useful as an INI correlating with postoperative severe complications and as a prognostic indicator for ICC