55 research outputs found
Correlative Spectral Analysis of Gamma-Ray Bursts using Swift-BAT and GLAST-GBM
We discuss the preliminary results of spectral analysis simulations involving
anticipated correlated multi-wavelength observations of gamma-ray bursts (GRBs)
using Swift's Burst Alert Telescope (BAT) and the Gamma-Ray Large Area Space
Telescope's (GLAST) Burst Monitor (GLAST-GBM), resulting in joint spectral
fits, including characteristic photon energy (Epeak) values, for a conservative
annual estimate of ~30 GRBs. The addition of BAT's spectral response will (i)
complement in-orbit calibration efforts of GBM's detector response matrices,
(ii) augment GLAST's low energy sensitivity by increasing the ~20-100 keV
effective area, (iii) facilitate ground-based follow-up efforts of GLAST GRBs
by increasing GBM's source localization precision, and (iv) help identify a
subset of non-triggered GRBs discovered via off-line GBM data analysis. Such
multi-wavelength correlative analyses, which have been demonstrated by
successful joint-spectral fits of Swift-BAT GRBs with other higher energy
detectors such as Konus-WIND and Suzaku-WAM, would enable the study of
broad-band spectral and temporal evolution of prompt GRB emission over three
energy decades, thus potentially increasing the science return without placing
additional demands upon mission resources throughout their contemporaneous
orbital tenure over the next decade.Comment: 5 pages. Adapted from a contribution to the Proceedings of the 2008
Nanjing GRB Conference. Edited by Y. F. Huang, Z. G. Dai and B. Zhan
A Correlation of Spectral Lag Evolution with Prompt Optical Emission in GRBs?
We report on observations of correlated behavior between the prompt gamma-ray
and optical emission from GRB 080319B, which (i) strongly suggest that they
occurred within the same astrophysical source region and (ii) indicate that
their respective radiation mechanisms were most likely dynamically coupled. Our
preliminary results, based upon a new cross-correlation function (CCF)
methodology for determining the time-resolved spectral lag, are summarized as
follows. First, the evolution in the arrival offset of prompt gamma-ray photon
counts between Swift-BAT 15-25 keV and 50-100 keV energy bands (intrinsic
gamma-ray spectral lag) appears to be anti-correlated with the arrival offset
between prompt 15-350 keV gamma-rays and the optical emission observed by
TORTORA (extrinsic optical/gamma-ray spectral lag), thus effectively
partitioning the burst into two main episodes at ~T+28+/-2 sec. Second, prompt
optical emission is nested within intervals of (a) trivial intrinsic gamma-ray
spectral lag (~T+12+-2 and ~T+50+/-2 sec) with (b) discontinuities in the hard
to soft evolution of the photon index for a power law fit to 15-150 keV
Swift-BAT data (~T+8+/-2 and ~T+48+/-1 sec), both of which coincide with the
rise (~T+10+/-1 sec) and decline (~T+50+/-1 sec) of prompt optical emission.
This potential discovery, robust across heuristic permutations of BAT energy
channels and varying temporal bin resolution, provides the first observational
evidence for an implicit connection between spectral lag and the dynamics of
shocks in the context of canonical fireball phenomenology.Comment: 5 pages. Adapted from a contribution to the Proceedings of the 2008
Nanjing GRB Conference. Edited by Y. F. Huang, Z. G. Dai and B. Zhan
An Efficient Strategy to Construct a Better Differential on Multiple-Branch-Based Designs: Application to Orthros
As low-latency designs tend to have a small number of rounds to decrease latency, the differential-type cryptanalysis can become a significant threat to them.
In particular, since a multiple-branch-based design, such as Orthros can have the strong clustering effect on differential attacks due to its large internal state, it is crucial to investigate the impact of the clustering effect in such a design.
In this paper, we present a new SAT-based automatic search method for evaluating the clustering effect in the multiple-branch-based design.
By exploiting an inherent trait of multiple-branch-based designs, our method enables highly efficient evaluations of clustering effects on this-type designs. % that a conventional method by automatic search tools.
We apply our method to the low-latency PRF Orthros, and show a best differential distinguisher reaching up to 7 rounds of Orthros with time/data complexity and 9-round distinguisher for each underlying permutation which is 2 more rounds than known longest distinguishers.
Besides, we update the designer\u27s security bound for differential attacks based on the lower bounds for the number of active S-boxes, and obtain the optimal differential characteristic of Orthros, Branch 1, and Branch 2 for the first time.
Consequently, we improve the designer\u27s security bound from 9/12/12 to 7/10/10 rounds for Orthros/Branch 1/Branch 2 based on a single differential characteristic
Wavefunction Analysis of STM Image: Surface Reconstruction of Organic Charge Transfer Salts
In this chapter, the wavefunction analysis is demonstrated, applied to the organic charge transfer salts composed of electron donor and electron acceptor molecules. Scanning tunneling microscopy (STM) images of the surface donor layers in the three charge transfer salts, α-(BEDT-TTF)2I3, β-(BEDT-TTF)2I3, and (EDO-TTF)2PF6, are analyzed with the atomic π electron orbitals of sulfur, oxygen, and carbon atoms. We have deduced three different kinds of surface molecular reconstructions as follows: (1) charge redistribution in α-(BEDT-TTF)2I3, (2) translational reconstruction up to 0.1 nm in β-(BEDT-TTF)2I3, and (3) rotational reconstruction transforming the 1D axis from the a axis to the b axis in (EDO-TTF)2PF6. Finally, it is concluded that the surface reconstruction is ascribed to the additional gain of the cohesive energy of the π electron system, provoked by the reduced steric hindrance with the anions of the missing outside double layer. The investigations of the surface states provide not only interesting behaviors of the surface cation layer, but also important insights into the electronic states of a lot of similar charge transfer crystals, as demonstrated in α-(BEDT-TTF)2I3
Identification of oxidative stress-regulated genes in rat aortic smooth muscle cells by suppression subtractive hybridization
AbstractA suppression subtractive hybridization technique was used to identify reactive oxygen species (ROS)-regulated genes in rat vascular smooth muscle cells. Three genes out of 89 clones, identified as fibronectin, p105 coactivator and ECA39, showed increased expression after treatment with H2O2. The mRNA expressions of these three genes were induced in a time- and dose-dependent manner, independent of protein kinase C activation. Immunohistochemical staining showed that the p105 coactivator expression was markedly induced in the neointima of balloon-injured rat carotid arteries. These results suggest that ROS may play an important role in the development of atherosclerosis by regulating the gene expressions we identified in this study
Osteocalcin and body fat in type 1 diabetes
The objective of the present study was to investigate the correlations between serum under-carboxylated osteocalcin (ucOC) or osteocalcin (OC) concentrations and %body fat, serum adiponectin and free-testosterone concentration, muscle strength and dose of exogenous insulin in patients with type 1 diabetes. We recruited 73 Japanese young adult patients with childhood-onset type 1 diabetes. All participants were receiving insulin replacement therapy. The correlations between logarithmic serum ucOC or OC concentrations and each parameter were examined. Serum ucOC and OC concentrations were inversely correlated with% body fat (r = -0.319, P = 0.007; r = -0.321, P = 0.006, respectively). Furthermore, multiple linear regression analyses were performed to determine whether or not serum ucOC or OC concentrations were factors associated with %body fat. Serum ucOC and OC concentrations remained significant factors even after adjusting for gender, HbA1c, body weight-adjusted total daily dose of insulin and duration of diabetes (β = -0.260, P = 0.027; β = -0.254, P = 0.031, respectively). However, serum ucOC and OC concentrations were not correlated with serum adiponectin or free-testosterone concentrations, muscle strength or dose of exogenous insulin. In conclusion, our study demonstrates the inverse correlation between serum ucOC or OC concentrations and body fat in patients with type 1 diabetes
The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)
Background and purposeThe Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 and published in the Journal of JSICM, [2017; Volume 24 (supplement 2)] https://doi.org/10.3918/jsicm.24S0001 and Journal of Japanese Association for Acute Medicine [2017; Volume 28, (supplement 1)] http://onlinelibrary.wiley.com/doi/10.1002/jja2.2017.28.issue-S1/issuetoc.This abridged English edition of the J-SSCG 2016 was produced with permission from the Japanese Association of Acute Medicine and the Japanese Society for Intensive Care Medicine.MethodsMembers of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ) and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (> 66.6%) majority vote of each of the 19 committee members.ResultsA total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation, and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty-seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for five CQs.ConclusionsBased on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals
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