Flares from merged magnetars: their prospects as a new population of gamma-ray counterparts of binary neutron star mergers

Long-lived massive magnetars are expected to be remnants of some binary neutron star (BNS) mergers. In this paper, we argue that the magnetic powered flaring activities of these merged magnetars would occur dominantly in their early millisecond-period-spin phase, which is in the timescale of days. Such flares endure significant absorption by the ejecta from the BNS collision, and their detectable energy range is from 0.1-10 MeV, in a time-lag of $\sim$ days after the merger events indicated by the gravitational wave chirps. We estimate the rate of such flares in different energy ranges, and find that there could have been ~0.1-10 cases detected by Fermi/GBM. A careful search for $\sim10$ milliseconds spin period modulation in weak short gamma-ray bursts (GRBs) may identify them from the archival data. Future MeV detectors can detect them at a rate from a few to tens per year. The recent report on the Quasi-Period-Oscillation found in two BASTE GRBs should not be considered as cases of such flares, for they were detection in a lower energy range and with a much shorter period spin modulation.Comment: 10 pages, 5 figures, submitted to ApJ

Association Between Bone Mineral Density, Bone Turnover Markers, and Serum Cholesterol Levels in Type 2 Diabetes

Purpose: The association between bone mineral density (BMD), bone turnover markers, and serum cholesterol in healthy population has already been proved. However, in patients with type 2 diabetes mellitus (T2D), it has not been adequately analyzed. In this study, we investigated the correlation between BMD, bone turnover markers, and serum cholesterol levels in people with T2D.Methods: We enrolled 1,040 men and 735 women with T2D from Zhongshan Hospital between October 2009 and January 2013. Their general condition, history of diseases and medication, serum markers, and BMD data were collected. We used logistic regression analysis to identify the association between serum cholesterol levels and BMD as well as bone turnover markers.Results: In multivariate regression analysis, we observed that in men with T2D, high high-density lipoprotein-cholesterol and total cholesterol levels were significantly associated with low total lumbar, femur neck, and total hip BMD, while low-density lipoprotein-cholesterol level was only inversely associated with total lumbar and femur neck BMD. Total cholesterol and low-density lipoprotein-cholesterol levels were also negatively associated with osteocalcin, procollagen type I N-terminal propeptide, and β-crosslaps. In women with T2D, high-density lipoprotein-cholesterol level was observed to be negatively correlated with total lumbar, femur neck, and total hip BMD, while total cholesterol and low-density lipoprotein-cholesterol levels were only associated with BMD at the total lumbar. Furthermore, total cholesterol was also negatively associated with osteocalcin, procollagen type I N-terminal propeptide, and β-crosslaps; high-density lipoprotein-cholesterol was only related to osteocalcin and parathyroid hormone, while low-density lipoprotein-cholesterol was only related to β-crosslaps in women.Conclusion: Our study suggests a significantly negative correlation between serum cholesterol levels and BMD in both men and women with T2D. The associations between serum cholesterol levels and bone turnover markers were also observed in T2D patients

Flares from Merged Magnetars: Their Prospects as a New Population of Gamma-Ray Counterparts of Binary Neutron Star Mergers

Long-lived massive magnetars are expected to be remnants of some binary neutron star (BNS) mergers. In this paper, we argue that the magnetic powered flaring activities of these merged magnetars would occur dominantly in their early millisecond-period-spin phase, which is in the timescale of days. Such flares endure significant absorption by the ejecta from the BNS collision, and their detectable energy range is from 0.1 to 10 MeV, in a time lag of approximately days after the merger events indicated by the gravitational wave chirps. We estimate the rate of such flares in different energy ranges, and find that there could have been 0.1–10 cases detected by Fermi/GBM. A careful search for ∼10 ms spin-period modulation in weak short gamma-ray bursts (GRBs) may identify them from the archival data. The next-generation megaelectronvolt detectors could detect them at a mildly higher rate. The recent report on the Quasi-Period-Oscillation found in two BASTE GRBs should not be considered as cases of such flares, for they were detected in a lower energy range and with a much shorter period spin modulation

Association between renal function and bone mineral density in patients with type 2 diabetes mellitus

Background: This study evaluated the association between renal function, assessed by serum creatinine and estimated glomerular filtration rate (eGFR) according to the Cockcroft–Gault (CG) and Modification of Diet in Renal Disease (MDRD) equations, and bone mineral density (BMD) in Chinese patients with type 2 diabetes mellitus (T2DM). Methods: 1322 patients with T2DM were included, and their basic clinical information, serum biochemical tests, and BMD at the total hip and femur neck were collected. Multivariate adjusted linear regression, smooth curve fitting and a piecewise linear regression model were used to analyze linear and nonlinear associations. Age, BMI, drinking, smoking, systolic blood pressure and diastolic blood pressure, FBG, HbA1C, course of diabetes, hsCRP, TC, TG, HDL-C, LDL-C, Ca, P, PTH, ALP, OC, P1NP, β-CTX and 25(OH)D were adjusted. Results: After adjusting the variables, no correlation between eGFR CG and eGFR MDRD and femur neck BMD was observed in women, men, or the total population. The eGFR CG and eGFR MDRD had a significant positive association with total hip BMD in men and the total population with T2DM. With a 10-unit decrease in eGFR CG, total hip BMD reduced by 0.012 g/cm2 in men and 0.010 g/cm2 the total population. Total hip BMD reduced by 0.014 g/cm2 in men and 0.022 g/cm2 in the total population with a 10-unit decrease in eGFR MDRD. There was no correlation between eGFR CG or eGFR MDRD and total hip BMD in female participants. Conclusion: Impaired renal function was associated with decreased total hip BMD in men and the total population with T2DM. No associated between renal function with femur neck BMD was observed

Halide vapor phase epitaxy of monolayer molybdenum diselenide single crystals

Single-crystalline transition metal dichalcogenides (TMD) films are of potential application in future electronics and optoelectronics. In this work, a halide vapor phase epitaxy (HVPE) strategy was proposed and demonstrated for the epitaxy of molybdenum diselenide (MoSe2) single crystals, in which metal halide vapors were in-situ produced by the chlorination of molybdenum as sources for the TMD growth. Combined with the epitaxial sapphire substrate, unidirectional domain alignment was successfully achieved and monolayer single-crystal MoSe2 films have been demonstrated on a 2-inch wafer for the first time. A series of characterizations ranging from centimeter to nanometer scales have been implemented to demonstrate the high quality and uniformity of the MoSe2. This work provides a universal strategy for the growth of TMD single-crystal films.</p

Halide vapor phase epitaxy of monolayer molybdenum diselenide single crystals

Single-crystalline transition metal dichalcogenides (TMD) films are of potential application in future electronics and optoelectronics. In this work, a halide vapor phase epitaxy (HVPE) strategy was proposed and demonstrated for the epitaxy of molybdenum diselenide (MoSe2) single crystals, in which metal halide vapors were in-situ produced by the chlorination of molybdenum as sources for the TMD growth. Combined with the epitaxial sapphire substrate, unidirectional domain alignment was successfully achieved and monolayer single-crystal MoSe2 films have been demonstrated on a 2-inch wafer for the first time. A series of characterizations ranging from centimeter to nanometer scales have been implemented to demonstrate the high quality and uniformity of the MoSe2. This work provides a universal strategy for the growth of TMD single-crystal films