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The standard external shock model in the thin-shell scenario predicts an onset bump in the early optical afterglow light curves of gamma-ray bursts (GRBs). We collect such a textbook-version light-curve sample of 30 GRBs and derive the jet properties from our joint fit to their X-ray and optical afterglow light curves. It is found that the distributions of the isotropic initial Lorentz factors (Γ0), the deceleration radii (R dec), and the magnetic field strength (B 0) are log-normal, but the distributions of the isotropic kinetic energy (E k,iso), medium density (n 0), and magnetization parameter (σ B ≡ ϵ B /ϵ e ) are tentatively bimodal. A tight R dec–B 0–σ B relation is found. It infers a universal ϵ e E k,iso among bursts, plausibly supporting the previous argument of a universal GRB radiation energy among GRBs. A jet break is required for modeling the light curves of 26 GRBs. The distributions of the jet opening angles and the jet-corrected kinetic energies log-normally center at logθj,c/rad=−1.51 (standard deviation σ = 0.27) and log(Ek,j,c/erg)=51.78 (σ = 0.54), respectively. Those GRBs (19 GRBs), whose prompt gamma-ray emission is well estimated with broad energy-band observations, satisfy the previously discovered L γ,p,iso–E p,z–Γ0 relation, and their gamma-ray radiation efficiencies log-normally distribute in the range from 0.04% to 10% with a central value of 0.42%. Such a low efficiency favors the baryonic fireball model, and the distribution of their baryon mass loading in the GRB ejecta log-normally centers at log(Mfb,c/M☉)=−5 (σ = 0.75).

Introduction The 1-year mortality rate after femoral intertrochanteric fracture is higher than that of femoral neck fracture, which also belongs to hip fracture (Cui et al. in Arch Osteoporos 14(1):55, 2019). With the application of the concept of co-management model of orthopedics and geriatrics, the short-term and long-term mortality of all types of hip fractures has decreased (Van Heghe et al. in Calcif Tissue Int, 2021, https://doi.org/10.1007/s00223-021-00913-5 ). However, the mortality of Chinese femoral intertrochanteric fracture patients under this model has not been reported in the literatures. Aim This paper aims to study the risk factors of postoperative all-cause mortality in aged patients with femoral intertrochanteric fracture under the co-management model of orthopedics and geriatrics. Materials and methods This is a single-center prospective cohort study based on the real world, under the co-management of orthopedics and geriatrics, 363 patients aged ≥ 65 years with femoral intertrochanteric fracture were enrolled and followed up for 2–3 years; 52 patients were lost to follow up. Age, gender, body mass index (BMI), history of comorbidities, hip Bone Mineral Density (BMD), fracture history, 25(OH)D level, hemoglobin level, anti-osteoporosis treatment were risk factors to be tested. Kaplan–Meier survival curves and multivariate Cox proportional hazards models were constructed to analyze the impact of factors on all-cause mortality. Results (1) Most of the dead patients were older (the mean age was 83.4 years, compared with 79.8 years for surviving patients), with more complications and without anti-osteoporosis medication; gender, pre-fracture history, BMI, total hip BMD, hemoglobin, 25(OH)D had no difference between the dead and the living patients. (2) Elderly patients with Intertrochanteric fracture can benefit from the early treatment of Zoledronic Acid (within 3 days after the operation). Conclusion Under the co-management of orthopedics and geriatrics, to Chinese patients with Femoral Intertrochanteric fracture, Doctors should pay more attention to their age and chronic disease, and give anti-osteoporosis treatment if allowed.

Background Cancer-associated fibroblasts (CAFs) and vasculogenic mimicry (VM) play important roles in the occurrence and development of tumors. However, the relationship between CAFs and VM formation, especially in gallbladder cancer (GBC) has not been clarified. In this study, we investigated whether gallbladder CAFs (GCAFs) can promote VM formation and tumor growth and explored the underlying molecular mechanism. Methods A co-culture system of human GBC cells and fibroblasts or HUVECs was established. VM formation, proliferation, invasion, migration, tube formation assays, CD 31 -PAS double staining, optic/electron microscopy and tumor xenograft assay were used to detect VM formation and malignant phenotypes of 3-D co-culture matrices in vitro, as well as the VM formation and tumor growth of xenografts in vivo, respectively. Microarray analysis was used to analyze gene expression profile in GCAFs/NFs and VM (+)/VM (−) in vitro. QRT-PCR, western blotting, IHC and CIF were used to detected NOX4 expression in GCAFs/NFs, 3-D culture/co-culture matrices in vitro, the xenografts in vivo and human gallbladder tissue/stroma samples. The correlation between NOX4 expression and clinicopathological and prognostic factors of GBC patients was analyzed. And, the underlying molecular mechanism of GCAFs promoting VM formation and tumor growth in GBC was explored. Results GCAFs promote VM formation and tumor growth in GBC; and the finding was confirmed by facts that GCAFs induced proliferation, invasion, migration and tube formation of GBC cells in vitro, and promoted VM formation and tumor growth of xenografts in vivo. NOX4 is highly expressed in GBC and its stroma, which is the key gene for VM formation, and is correlated with tumor aggression and survival of GBC patients. The GBC patients with high NOX4 expression in tumor cells and stroma have a poor prognosis. The underlying molecular mechanism may be related to the upregulation of NOX4 expression through paracrine IL-6 mediated IL-6/JAK/STAT3 signaling pathway. Conclusions GCAFs promote VM formation and tumor growth in GBC via upregulating NOX4 expression through the activation of IL-6-JAK-STAT3 signal pathway. NOX4, as a VM-related gene in GBC, is overexpressed in GBC cells and GCAFs, which is related to aggression and unfavorable prognosis of GBC patients.

A newly born millisecond magnetar has been proposed as one possible central engine of some gamma-ray bursts (GRBs) with X-ray plateau emission. In this work, we systematically analyzed the Swift/X-Ray Telescope data of long GRBs with plateau emission that were detected before 2023 December, estimated the physical parameters of the magnetar by considering the R/I evolutionary effects, and investigated possible relationships among these parameters and their relation to the GRB jet and magnetar wind radiation. We found that neglecting the evolutionary effects of R/I can lead to systematic overestimation or underestimation of magnetar physical parameters such as magnetic field strength (Bp), spin period (P0), and ellipticity (ϵ) from 20% to 50%. We also found that the correlations among different magnetar parameters can be approximately expressed as ϵ∝P01.57±0.22 , ϵ∝Bp0.97±0.13 , and Bp∝P01.30±0.16 for our selected equation of states (EoSs), with the 1σ deviation included. The correlations between the GRB jet emission and the magnetar wind emission can be approximately described as Ewind∝Ejet,iso0.83±0.07(Ejet0.76±0.06) , P0∝Ejet,iso−0.29±0.03(Ejet−0.26±0.02) , Bp∝Ejet,iso−0.58±0.06(Ejet−0.55±0.05) , and ϵ∝Ejet,iso−0.55±0.07(Ejet−0.52±0.06) for our selected EoSs. The universal correlations suggest that a nascent magnetar with the faster P0, lower Bp, as well as lower ϵ are more inclined to power a more energetic GRB jet, and the ellipticity deformation and initial spin period of the newborn magnetar are likely to originate from the magnetically induced distortion mechanism and correspond to the equilibrium spin period as a result of interaction between the magnetar and its accretion disk, respectively. Finally, we found that the gravitational-wave (GW) signals from the remnants of those GW-dominated GRBs with redshift measurements cannot reach the sensitivity threshold of the current Advanced LIGO detector, and only two cases (GRB 150323A and 170607A) can reach the sensitivity threshold of the prospective ET detector. Future GW observations could not only offer the first smoking gun that a protomagnetar can serve as the central engine of GRBs but also play a crucial role in precisely constraining the neutron star EoS.

Introduction The mortality rate after hip fracture is high. However, the 1-year mortality rate after femoral intertrochanteric fracture and femoral neck fracture differs (Gibson-Smith D, Klop C, Elders PJ, Welsing PM, van Schoor N, Leufkens HG, et al., Osteoporos Int 25:2555-2563, 2014), although both are types of hip fracture. A previous real-world single-center prospective cohort study showed that older age and high Charlson comorbidity index score were risk factors for femoral intertrochanteric fracture. Additionally, therapy with zoledronic acid 5 mg (Aclasta) was a protective factor (Li XP, Zhang P, Zhu SW, Yang MH, Wu XB, Jiang XY, J Orthop Surg Res. 16:727, 2021). We wished to determine the risk factors for all-cause mortality in femoral neck fracture patients. Aim To identify the risk factors for postoperative all-cause mortality in aged patients with femoral neck fracture. Materials and methods We enrolled 307 aged patients with femoral neck fracture; 38 were lost to follow-up after 2–3 years. The patients’ general characteristics, bone mineral density, and anti-osteoporosis treatment after operation were recorded as potential risk factors. Kaplan–Meier curves and multivariate Cox proportional hazards models were constructed to analyze the influence of each factor on all-cause mortality. Results This was a real-world single-center prospective cohort study showing that (1) most of the patients who died were male, older (mean age of the patients who died: 84.8 years vs. 77.9 years for survivors), and had more comorbidities compared with surviving patients. Previous fracture history, body mass index, femoral neck T score, hemoglobin and 25-hydroxy vitamin D levels did not differ significantly between patients who died vs. survived. (2) Differing from patients with intertrochanteric fractures, older patients with femoral neck fracture experienced no reduction in all-cause mortality with treatment with zoledronic acid. Conclusion In Chinese patients with femoral neck fracture, physicians should pay careful attention to male patients, older patients, and those with high numbers of comorbidities.

M-type stars are the ones that flare most frequently, but how big their maximum flare energy can reach is still unknown. We present 163 flares from 162 individual M2 through L1-type stars that triggered the GWAC, with flare energies ranging from 1032.2 to 1036.4 erg. The flare amplitudes range from △G = 0.84 to ∼10 mag. Flare energy increases with stellar surface temperature (T eff) but both △G and equivalent duration log10(ED) seem to be independent of T eff. Combining periods detected from light curves of TESS and K2, spectra from LAMOST, the Sloan Digital Sky Survey, the 2.16 m telescope, and the Gaia DR3 data, we found that these GWAC flare stars are young. For the stars that have spectra, we found that these stars are in or very near the saturation region, and log10(LHα/Lbol) is lower for M7–L1 stars than for M2–M6 stars. We also studied the relation between GWAC flare bolometric energy E bol and stellar hemispherical area S, and found that log10Ebol (in erg) increases with increasing S (in square centimeters), and the maximum flare energy log10Ebol,max≥log10S+14.25 . For M7–L1 stars, there seem to be other factors limiting their maximum flare energies in addition to the stellar hemispherical area.

We present photometric and spectroscopic observations and analysis of the Type IIb supernova (SN) SN 2019tua, which exhibits multiple bumps in its declining light curves between 40 and 65 days after discovery. SN 2019tua shows a time to peak of about 25 days, similar to other Type IIb SNe. Our observations indicate a decrease in its brightness of about 1 mag in the 60 days after the peak. At about days 50 and 60, its multiband light curves exhibit bumpy behavior. The complex luminosity evolution of SN 2019tua could not be well modeled with a single currently popular energy source model, e.g., radioactive decay of 56Ni, magnetar, interaction between the ejecta and a circumstellar shell. Even though the magnetar model has a smaller χ 2/dof value, the complex changes in SN 2019tua’s brightness suggest that more than one physical process might be involved. We propose a hybrid circumstellar medium (CSM) interaction plus 56Ni model to explain the bolometric light curve of SN 2019tua. The fitting results show that the ejecta mass M ej ≈ 2.4 M ⊙, the total CSM mass M CSM ≈ 1.0 M ⊙, and the 56Ni mass M Ni ≈ 0.4 M ⊙. The total kinetic energy of the ejecta is E k ≈ 0.5 × 1051 erg. Preexisting multiple shells suggest that the progenitor of SN 2019tua experienced mass ejections within approximately ∼6–44 yr prior to the explosion.

Gemcitabine (GEM), as an anti-metabolic nucleoside analog, has been shown to have anticancer effects in various tumors, but its chemotherapy resistance is still an important factor leading to poor prognosis of cancer patient. A large number of studies in recent years have shown that autophagy plays an important role in the chemotherapy sensitivity of many tumors, including pancreatic, non-small cell lung, and bladder cancer. However, whether GEM causes autophagy in gallbladder cancer (GBC) and whether it is related to chemotherapy resistance is unknown. In the present study, we demonstrated that GEM induced apoptosis and protective autophagy in GBC cells, which may be related to the AKT/mTOR signaling pathway, and GEM in combination with autophagy inhibitor chloroquine can strengthen the cytotoxic effect of GEM on GBC in vitro and in vivo. These findings showed that both autophagy and AKT/mTOR signals were engaged in GBC cell death evoked by GEM, GBC patients might benefit from this new treatment strategy, and molecular targeted treatment in combination with autophagy inhibitors shows promise as a treatment improvement.

IntroductionBone turnover markers (BTMs) can be used to monitor bone metabolism, while the actual clinical changing in hip fracture had not been certified to evaluate the changes of BTMs during the healing process after surgery of elderly hip fractures; and to get the effects of operation type, gender, serum 25(OH)D level, and age on bone turnover markers.Materials and methodsA total of 100 elderly cases with hip fracture were selected, including 74 females and 26 males, and the patients were followed to 180–230 days after surgery. Serum levels of N-propeptide of type 1 collagen (P1NP), C-terminal crosslinking telopeptides of type 1 collagen (CTX), Osteocalcin (OC), and 25 hydroxy vitamin D (25OHD) were investigated. Bone mineral density (BMD) was measured with dual-energy X-ray absorptiometry (DXA).Results(1) P1NP and CTX showed peak time at 30–60 days after operation, while OC keep going even at 180–230 days; P1NP showed less than 4 times elevation during healing, CTX and OC only had less than 2 times rise. (2) Female had higher serum CTX and OC than male, intramedullary nailing for intertrochanteric fracture patients had higher P1NP than hip replacement for femoral neck fracture patients, and both the degrees of increase were less than 50%. (3) Serum average 25(OH)D level had no effect on BTMs during the fracture healing; different from the young old (65–84 years), serum OC level of eldest older patients(≥ 85 years) decreased early in the process of fracture healing.ConclusionsBTMs reached the peak level in 30–60 days after surgery, P1NP showed less than 4 times elevation, and CTX and OC had less than 2 times rise. It was not necessary to take gender into account when observing P1NP, and it was not necessary to take fracture and operation type into account when observing CTX and OC.

Early optical observations of gamma-ray bursts can significantly contribute to the study of the central engine and physical processes therein. However, of the thousands observed so far, only a few have data at optical wavelengths in the first minutes after the onset of the prompt emission. Here we report on GRB 190106A, whose afterglow was observed in optical bands just 36 s after the Swift/BAT trigger, i.e., during the prompt emission phase. The early optical afterglow exhibits a bimodal structure followed by a normal decay, with a faster decay after ∼T 0 + 1 day. We present optical photometric and spectroscopic observations of GRB 190106A. We derive the redshift via metal absorption lines from Xinglong 2.16 m/BFOSC spectroscopic observations. From the BFOSC spectrum, we measure z = 1.861 ± 0.002. The double-peak optical light curve is a significant feature predicted by the reverse-forward external-shock model. The shallow decay followed by a normal decay in both the X-ray and optical light curves is well explained with the standard forward-shock model with late-time energy injection. Therefore, GRB 190106A offers a case study for GRB emission from both reverse and forward shocks.