Well-sampled optical lightcurves of 146 gamma-ray bursts (GRBs) are compiled from the literature. By empirical fitting we identify eight possible emission components and summarize results in a "synthetic" lightcurve. Both flare early shallow-decay likely related to long-term central engine activities. We focus on their statistical properties this paper. Twenty-four flares obtained 19 GRBs. The isotropic R-band energy is smaller than 1% $E_{\gamma, \rm iso}$. relation between luminosities...

We continue our systematic statistical study of various components gamma-ray burst (GRB) optical light curves. decompose the early onset bump and late re-brightening with empirical fits analyze their properties. Among 146 GRBs that have well-sampled curves, bumps are observed in 38 26 GRBs, respectively. It is found typical rising decaying slopes for both ∼1.5 ∼ − 1.15, No X-ray band detected to be associated bumps, while an half bumps. The peak luminosity anti-correlated time Both Lp...

The durations (T90) of 315 GRBs detected with Fermi/GBM (8-1000 keV) by 2011 September are calculated using the Bayesian Block method. We compare T90 distributions between this sample and those derived from previous/current GRB missions. show that distribution is bimodal, a statistical significance level being comparable to BeppoSAX/GRBM Swift/BAT sample, but lower than CGRO/BATSE sample. short-to-long number ratio also much BATSE i.e., 1:6.5 vs 1:3. measure in several bands, 8-15, 15-25,...

Gamma-ray Burst (GRB) collimation has been inferred with the observations of achromatic steepening in GRB light curves, known as jet breaks. Identifying a break from afterglow lightcurve allows measurement opening angle and true energetics GRBs. In this paper, we reinvestigate problem using large sample GRBs that have an optical which is consistent being X-ray band. Our includes 99 February 1997 to March 2015 and, for Swift GRBs, lightcurves are interpretation. Out studied, 55 found temporal...

We fit the spectral energy distributions of a GeV–TeV flat spectrum radio quasar (FSRQ) sample with leptonic model. Their γmin relativistic electron distributions, which significantly affect estimate jet properties, are constrained, typical value ∼48. power, magnetized parameter, radiation efficiency, and production rates per central black hole (BH) mass derived compared those BL Lacertae (BL Lac) objects. show that FSRQ jets may be dominated by Poynting flux have high whereas Lac object...

We jointly analyze the gamma-ray burst (GRB) data observed with BAT and XRT on board Swift mission to present a global view internal energy dissipation processes in GRBs, including precursors, prompt emission, extended soft late X-ray flares. The Bayesian block method is utilized lightcurves identify various emission episodes. Our results suggest that these components likely share same physical origin, which repeated activation of GRB central engine. What we observe band may be...

We select a sample of 34 gamma-ray bursts (GRBs) whose Γ0 values are derived with the onset peaks observed in afterglow light curves (except for GRB 060218, is estimated its radio data), and investigate correlations among Γ0, isotropic peak luminosity (Liso), energy (Ep,z) spectrum cosmological rest frame. An analysis pair these observables well confirms results reported by previous papers. More interestingly, tight correlation Liso, Ep,z, found from multiple regression analysis, which takes...

Hyperthermia and oxidative stresses are the two central elements contributing to varicocele-related sperm damage. Growing evidence indicates that microRNAs (miRNAs) involved in regulation of heat stress responses. In this study, we analyzed expressions several stress-related miRNAs found expression miR-15a was significantly decreased patients with varicocele compared control. Furthermore, repressed HSPA1B, which is a typical stress-induced chaperone protein, through directly binding its...

In this work, we re-analyze the Fermi-LAT observation of NGC 1275 to search for axion-like particle (ALP) effects and constrain ALP parameters. Instead fitting observed spectrum with models, adopt an alternative method analysis source which calculates irregularity spectrum. With newly used method, find no spectral oscillation rule out couplings $g_{a\gamma}>3\times10^{-12}\,{\rm GeV^{-1}}$ around mass $m_a\sim$ 1 neV at 95\% confidence level, is more stringent than previous results. We also...

Abstract Some optically selected quasars exhibit Mg ii- associated absorption lines (AALs), and their origin remains unclear. In this paper, we compile a sample of 1769 quasars, with or without ii AALs, which 1689 are far-infrared (FIR) detected the rest not in FIR. For FIR undetected obtain stacks for both AAL quasars. Then, estimate star formation rates (SFRs) within quasar host galaxies based on luminosities derived from graybody components, find that, although AALs have significantly...

Anti-double-stranded DNA (anti-dsDNA) antibodies at abnormal titer are of considerable diagnostic value for systemic lupus erythematosus (SLE). Current assays detecting anti-dsDNA show divergent properties, emphasizing the importance selecting suitable assays. This study aims to investigate performance indirect immunofluorescence (IIF), digital liquid chip method (DLCM), chemiluminescence immunoassay (CLIA), and their combinations in SLE. We conducted a retrospective, single-center from 2022...

Since the launch of Swift satellite, detections high-z (z > 4) long gamma-ray bursts (LGRBs) have been rapidly growing, even approaching very early Universe (the record holder currently is z= 8.3). The observed LGRB rate shows significant excess over that estimated from star formation history. We investigate what may be responsible for this high productivity GRBs at through Monte Carlo simulations, with effective Swift/Burst Alert Telescope (BAT) trigger and redshift detection probabilities...

The prompt emission spectra of gamma-ray bursts (GRBs) usually have a dominant component that is well described by phenomenological "Band" function. physical origin this spectral debated. Although the traditional interpretation synchrotron radiation non-thermal electrons accelerated in internal shocks or magnetic dissipation regions, growing trend community to interpret as modified thermal from dissipative photosphere GRB fireball. We analyze time dependent spectrum 110721A detected {\em...

Abstract The radiation mechanism of the prompt emission gamma-ray bursts (GRBs) remains an open question. Although their spectra are usually well fitted with empirical Band function, which is widely believed to be fully nonthermal and interpreted as optically thin synchrotron emission, accumulating evidence shows that a thermal component actually exists. In this paper, multicolor blackbody (mBB) model proposed for time-integrated spectrum GRB 081221 by assuming power-law distribution...

Recently, Shen et al. (2005) studied the contributions of curvature effect fireballs to spectral lag and showed that observed lags could be accounted for by effect. Here we check their results performing a more precise calculation with both formulas presented in Qin (2004). Several other aspects which were not considered are investigated. We find case ultra-relativistic motions, identical as long whole fireball surface is concerned. In our analysis, previous conclusion detected confirmed,...

A time-resolved spectral analysis for a sample of 22 intense, broad gamma-ray burst (GRB) pulses from the Compton Gamma Ray Observatory (CGRO)/BATSE GRB is presented. We fit spectra with Band function and investigate correlation between observed flux (F) peak energy (Ep) νfν spectrum in rising decaying phases these pulses. Two kinds Ep evolution trends, i.e., hard-to-soft (two-thirds our sample) Ep-tracing-F (one-third sample), are different GRBs even same burst. No dependence feature on...

An apparent redshift dependence of the jet opening angles (θj) gamma-ray bursts (GRBs) is observed from current GRB sample. We investigate whether this can be explained with instrumental selection effects and observational biases by a bootstrapping method. Assuming that (1) rate follows star formation history cosmic metallicity (2) intrinsic distributions jet-corrected luminosity (Lγ) θj are Gaussian or power-law function, we generate mock Swift/Burst Alert Telescope (BAT) sample considering...

A large body of evidence indicates that microRNAs play a critical role in tumor initiation and progression by negatively regulating oncogenes or suppressor genes. Here, we report the expression miR-200a was notably downregulated 45 renal cell carcinoma (RCC) samples. Restoration suppressed proliferation, migration, invasion two RCC lines. Furthermore, used an epithelial-to-mesenchymal transition PCR array to explore putative target genes miR-200a. By performing quantitative real-time PCR,...

Abstract The spectral evolution and lag behavior of 92 bright pulses from 84 gamma-ray bursts observed by the Fermi Gamma-ray Burst Monitor (GBM) telescope are studied. These can be classified into hard-to-soft (H2S; 64/92), H2S-dominated-tracking (21/92), other tracking (7/92). We focus on relationship between lags H2S pulses. main trend (lag behavior) is estimated with <?CDATA $\mathrm{log}{E}_{p}\propto {k}_{E}\mathrm{log}(t+{t}_{0})$?> ( $\hat{\tau }\propto {k}_{\hat{\tau...

ABSTRACT The cosmic evolution of gamma-ray burst (GRB) luminosity is essential for revealing the GRB physics and using GRBs as cosmological probes. We investigate long with a large sample 258 Swift /BAT GRBs. By describing peak individual <?CDATA ${L}_{{\rm{p}}}\propto \text{}{(1+z)}^{k}$?> <?MML <mml:math> <mml:msub> <mml:mrow> <mml:mi>L</mml:mi> </mml:mrow> <mml:mi mathvariant="normal">p</mml:mi> </mml:msub> <mml:mo>&prop;</mml:mo> <mml:mtext/> <mml:msup> <mml:mo stretchy="true">(</mml:mo>...

X-ray flares of gamma-ray bursts (GRBs) are usually observed in the soft range and spectral coverage is limited. In this paper, we present an analysis 32 GRB that simultaneously by both Burst Alert Telescope X-Ray on board Swift mission, so a joint with wider possible. Our results show spectra 19 fitted absorbed single power law or Band function models. More interestingly, other 13 power-law model plus blackbody component. Phenomenally, these analogous to several GRBs thermal component, but...

Abstract The first detected gravitational wave GW170817 from a binary neutron star merger is associated with an important optical transient AT 2017gfo, which direct observation of kilonova. Recent observations suggest that the remnant compact object GW170817/GRB 170817A may be stable long-lived magnetized star. In this situation, there would pulsar wind nebula (PWN) embedded inside dynamic ejecta. PWN emission absorbed by ejecta or leak out system. We study effect on observed light curves...