Evaporation of a nonsingular Reissner-Nordstr\"om black hole and information loss problem

One of the attractive solutions to the information loss problem is that the event horizon does not appear in the process of gravitational collapse and subsequent evaporation once the spacetime singularity is regularized by some mechanism, as pointed out by Hayward and Frolov. In this paper, we examine whether this Hayward-Frolov scenario holds for the evaporation of a charged black hole. The process of collapse and evaporation is modeled with the charged Vaidya spacetime and two kinds of regularization of the central singularity are considered. Analyzing the spacetime structure of the evaporating black hole, we find that the appropriately regularized evaporating Reissner-Nordstr\"{o}m "black hole" has no event and Cauchy horizons, indicating the possibility that the Hayward-Frolov scenario may have sufficient generality as the solution to the information loss problem.Comment: 46 pages, 14 figure

Quantum key distribution with an efficient countermeasure against correlated intensity fluctuations in optical pulses

Quantum key distribution (QKD) allows two distant parties to share secret keys with the proven security even in the presence of an eavesdropper with unbounded computational power. Recently, GHz-clock decoy QKD systems have been realized by employing ultrafast optical communication devices. However, security loopholes of high-speed systems have not been fully explored yet. Here we point out a security loophole at the transmitter of the GHz-clock QKD, which is a common problem in high-speed QKD systems using practical band-width limited devices. We experimentally observe the inter-pulse intensity correlation and modulation-pattern dependent intensity deviation in a practical high-speed QKD system. Such correlation violates the assumption of most security theories. We also provide its countermeasure which does not require significant changes of hardware and can generate keys secure over 100 km fiber transmission. Our countermeasure is simple, effective and applicable to wide range of high-speed QKD systems, and thus paves the way to realize ultrafast and security-certified commercial QKD systems

Author Correction: Exposure to paternal tobacco smoking increased child hospitalization for lower respiratory infections but not for other diseases in Vietnam.

An amendment to this paper has been published and can be accessed via a link at the top of the paper

Cancer of the Pancreas in 125 Patients

In this report, we did a retrospective study of 125 patients with cancer of the pancreas. Seventeen (36.2%) of the 47 patients with cancer of the pancreatic head underwent resection; 11.2% died within 30 days of surgery, 33.3 survived the first year, and 13.3 survived the first three years. The longest survival was for five years. Nine (23%) of the 39 patients with cancer of the pancreatic body and tail underwent resection; 11.1% died within 30 days, 37.5% survived the first year, and none survived more than three years. The longest survival was for 35 months. Important factors affecting the prognosis were invasion by the cancer of veins or lymph vessels in the surrounding tissues, and metastasis to regional lymph nodes. Lymphatic drainage of small cancers of the pancreatic head were established early. Invasion to the retroperitoneal tissue in cancer of the pancreatic body and tail was more common than in cancer of the pancreatic head. For the patient of early cancer of the pancreas, we strongly recommend total pancreatectomy over WHIPPLE\u27s pancreatoduodenectomy, based on results of our analysis of the outcome in our patients following these two operations. Key words: Cancer of the pancreas, Total pancreatectomy, WHIPPLE\u27s pancreatoduodenectom

A Retrospective Study in the Diagnosis of 301 Jaundiced Cases

In the past 12 years, 301 patients with a total serum bilirubin over 2 mg/dl (reference interval 0.2-0.8 mg/dl) were admitted to the Second Department of Surgery, Nagasaki University School of Medicine, Japan. The purpose of this paper is to analyse the jaundiced cases and to evaluate the diagnostic accuracy of the following imaging techniques: Computed Tomography (CT), Ultrasonography (US), Drip Infusion Cholangiography (DIC), Endoscopic Retrograde Cholangio- pancreatography (ERCP), Percutaneous transhepatic Cholangiography (PTC) and Selective Celiac Angiography (SCAG). Of the 301 patients, 63 had carcinoma of the bile duct, 48 carcinoma of the pancreas, 26 carcinoma of the gallbladder, 16 hepatoma, 8 carcinoma of the ampulla of Vater, 83 cholelithiasis, 27 parenchymal liver disease, 9 congenital bile duct disease, 5 chronic pancreatitis, 14 other diseases, and 2 had no final diagnosis. CT was attempted in 33 of 170 patients with malignancy, and 22 of 129 patients with benignancy. A correct finding was obtained in 23 (69.7%) of the 33 patients and 18 (81.8%) of the 22 patients, respectively. US gave a correct finding in 28 (59.6 %) of 47 patients with malignancy, and 36 (69.2%) of 52 patients with benignancy. DIC gave a correct finding in 1 (5.6%) of 18 patients with malignancy, and 16 (42.1%) of 38 patients with benignancy. ERCP gave a correct finding in 33 (76.7%) of 43 patients with malignancy, and 38 (74.5%) of 51 patients with benignancy. PTC gave a correct finding i

ベトナムにおいて父親のたばこ煙の暴露は、下気道呼吸器感染症による小児入院リスクを上げるが、それ以外の疾患への影響はない

Exposure to environmental tobacco smoke (ETS) is an important modifiable risk factor for child hospitalization, although its contribution is not well documented in countries where ETS due to maternal tobacco smoking is negligible. We conducted a birth cohort study of 1999 neonates between May 2009 and May 2010 in Nha Trang, Vietnam, to evaluate paternal tobacco smoking as a risk factor for infectious and non-infectious diseases. Hospitalizations during a 24-month observation period were identified using hospital records. The effect of paternal exposure during pregnancy and infancy on infectious disease incidence was evaluated using Poisson regression models. In total, 35.6% of 1624 children who attended follow-up visits required at least one hospitalization by 2 years of age, and the most common reason for hospitalization was lower respiratory tract infection (LRTI). Paternal tobacco smoking independently increased the risk of LRTI 1.76-fold (95% CI: 1.24?2.51) after adjusting for possible confounders but was not associated with any other cause of hospitalization. The population attributable fraction indicated that effective interventions to prevent paternal smoking in the presence of children would reduce LRTI-related hospitalizations by 14.8% in this epidemiological setting.長崎大学学位論文 学位記番号:博(医歯薬)甲第995号 学位授与年月日:平成29年9月6日Author: Reiko Miyahara, Kensuke Takahashi, Nguyen Thi Hien Anh, Vu Dinh Thiem, Motoi Suzuki, Hiroshi Yoshino, Le Huu Tho, Hiroyuki Moriuchi, Sharon E. Cox, Lay Myint Yoshida, Dang Duc Anh, Koya Ariyoshi & Michio YasunamiCitation: Scientific Reports, 7, 45481; 2017Nagasaki University (長崎大学)課程博

Chronic Nicotine Exposure Induces Murine Aortic Remodeling and Stiffness Segmentation—Implications for Abdominal Aortic Aneurysm Susceptibility

Aim: Arterial stiffness is a significant risk factor for many cardiovascular diseases, including abdominal aortic aneurysms (AAA). Nicotine, the major active ingredient of e-cigarettes and tobacco smoke, induces acute vasomotor effects that may temporarily increase arterial stiffness. Here, we investigated the effects of long-term nicotine exposure on structural aortic stiffness.Methods: Mice (C57BL/6) were infused with nicotine for 40 days (20 mg/kg/day). Arterial stiffness of the thoracic (TS) and abdominal (AS) aortic segments was analyzed using ultrasound (PWV, pulse wave velocity) and ex vivo pressure myograph measurements. For mechanistic studies, aortic matrix-metalloproteinase (MMP) expression and activity as well as medial elastin architecture were analyzed.Results: Global aortic stiffness increased with nicotine. In particular, local stiffening of the abdominal segment occurred after 10 days, while thoracic aortic stiffness was only increased after 40 days, resulting in aortic stiffness segmentation. Mechanistically, nicotine exposure enhanced expression of MMP-2/-9 and elastolytic activity in both aortic segments. Elastin degradation occurred in both segments; however, basal elastin levels were higher in the thoracic aorta. Finally, MMP-inhibition significantly reduced nicotine-induced MMP activity, elastin destruction, and aortic stiffening.Conclusion: Chronic nicotine exposure induces aortic MMP expression and structural aortic damage (elastin fragmentation), irreversibly increasing aortic stiffness. This process predominantly affects the abdominal aortic segment, presumably due in part to a lower basal elastin content. This novel phenomenon may help to explain the role of nicotine as a major risk factor for AAA formation and has health implications for ECIGs and other modes of nicotine delivery

Chronic Nicotine Exposure Induces Murine Aortic Remodeling and Stiffness Segmentation - Implications for Abdominal Aortic Aneurysm Susceptibility

Aim: Arterial stiffness is a significant risk factor for many cardiovascular diseases, including abdominal aortic aneurysms (AAA). Nicotine, the major active ingredient of e-cigarettes and tobacco smoke, induces acute vasomotor effects that may temporarily increase arterial stiffness. Here, we investigated the effects of long-term nicotine exposure on structural aortic stiffness. Methods: Mice (C57BL/6) were infused with nicotine for 40 days (20 mg/kg/day). Arterial stiffness of the thoracic (TS) and abdominal (AS) aortic segments was analyzed using ultrasound (PVVV, pulse wave velocity) and ex vivo pressure myograph measurements. For mechanistic studies, aortic matrix-metalloproteinase (MMP) expression and activity as well as medial elastin architecture were analyzed. Results: Global aortic stiffness increased with nicotine. In particular, local stiffening of the abdominal segment occurred after 10 days, while thoracic aortic stiffness was only increased after 40 days, resulting in aortic stiffness segmentation. Mechanistically, nicotine exposure enhanced expression of MMP-2/-9 and elastolytic activity in both aortic segments. Elastin degradation occurred in both segments;however, basal elastin levels were higher in the thoracic aorta. Finally, MMP-inhibition significantly reduced nicotine-induced MMP activity, elastin destruction, and aortic stiffening. Conclusion: Chronic nicotine exposure induces aortic MMP expression and structural aortic damage (elastin fragmentation), irreversibly increasing aortic stiffness. This process predominantly affects the abdominal aortic segment, presumably due in part to a lower basal elastin content. This novel phenomenon may help to explain the role of nicotine as a major risk factor for AM formation and has health implications for ECIGs and other modes of nicotine delivery

Superconductivity and physical properties of Ba24Si100 determined from electric transport, specific-heat capacity, and magnetic susceptibility measurements

Both Ba24Si100 and Ba24Ge100 with crystallographically identical structure are found to be superconducting at 1.4 and 0.27 K, respectively. Physical properties of this superconductor Ba24Si100 are studied by electric transport, specific heat capacity, and magnetic susceptibility measurements. The density of states at the Fermi level NEF=0.148 states eV-1(Siatom)-1 and a distinct jump of Cp at the superconducting transition temperature ΔCp=0.272JK-1mol-1 are obtained. An exponential fit of Cp below the superconducting states gives an energy gap 2Δ=0.423meV and shows that this is a superconductor having s-wave character or isotropic energy gap. On the basis of our experimental data other important physical parameters are also derived