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关键词： accretion, accretion discs   stars: neutron   X-rays: binaries  

摘要： The luminous accreting pulsar SMC X-1 is an appropriate target to explore the accretion dynamics. SMC X-1 shows unique quasi-periodic flux variability of 40-65 d known as superorbital modulation. To constrain the accretion structure of SMC X-1 based on timing and spectral study, we have analysed X-ray data of SMC X-1 observed by Suzaku and the Nuclear Spectroscopic Telescope Array (NuSTAR) at various epochs between 2011 and 2022. The spectral analysis shows that the hydrogen column density ($N_\mathrm{H}$) increases from $1.1 \times 10<^>{22}\, \mathrm{cm<^>{-2}}$ to $1.24 \times 10<^>{23}\, \mathrm{cm<^>{-2}}$ as the flux decreases with the superorbital modulation. The neutral iron K$\alpha$ line at $6.4 \,{\rm keV}$ has a broad width of $0.3 \,{\rm keV}$, and its equivalent width increases as toward superorbital low states. The line broadening is consistent with Keplerian motion at the inner disc rather than the stellar wind velocity of the donor star. These findings support that the superorbital modulation is a consequence of X-ray attenuation by the warped accretion disc. To test this interpretation, we have conducted photon transport simulations of a system consisting of a neutron star, a warped disc, and optically thin disc atmosphere. Occultation of the central source by the disc successfully reproduces the observed variations in the equivalent width of neutral iron K$\alpha$ line, pulse profiles, and flux in hard X-rays. Notably, a disc precession angle of approximately $30<^>{\circ }$ can account for the observational features. For the radiation pattern of the photon source, the preferred beam width corresponds to a standard deviation of $30<^>{\circ }$.

关键词： antiobesity   GLP-1   obesity treatment   weight loss   weight management  

摘要： Objective This study aimed to determine doses of VK2735, a novel glucagon-like peptide-1/glucose-dependent insulinotropic polypeptide (GLP-1/GIP) receptor dual agonist, that are effective for weight loss over 13 weeks of *** VENTURE was a phase 2, randomized, double-blind, placebo-controlled, dose-ranging study of weekly subcutaneous VK2735 in adults with obesity or overweight and >= 1 weight-related comorbidity. Participants with diabetes mellitus were ineligible. The primary endpoint was percent change from baseline in body weight at Week 13. Secondary efficacy endpoints were observed and change from baseline weight loss and the proportion of participants losing >= 5% and >= 10% of baseline *** Study was conducted between August 2023 and February 2024. Mean weight reduction with active treatment ranged from 9.2 kg (2.5 mg dose) to 14.6 kg (15 mg dose), corresponding to 9.1% and 14.7% weight reductions, respectively;the placebo group had a 1.8 kg (1.7%) reduction. In the active treatment groups, 93% (130/140) of participants had a >= 5% weight reduction, compared with 12% (4/34) of participants with placebo treatment. The common adverse events (AEs) were gastrointestinal, which decreased in reported frequency after dose titration to steady *** All subcutaneous doses of VK2735 significantly reduced body weight. The AE profile of VK2735 was primarily gastrointestinal, with decreased reported frequency upon continued *** Registration *** identifier NCT06068946

关键词： firearm   pediatric trauma   pediatric gunshot wounds  

摘要： Objective:In the United States, firearm-related injuries are the leading cause of death in individuals aged 0 to 24 years and lead to substantial cost burden, mortality, and morbidity. This study identifies trends of pediatric firearm injury at this level I pediatric trauma center, which may inform violence prevention and firearm safety intervention at the local ***:This study is a retrospective review of the pediatric trauma registry at a level 1 pediatric trauma center of children (0 to 17.9 y) who presented between January 1, 2013 and December 31, 2022. Age, sex, race, ethnicity, number of GSWs, location of injury, disposition, intention, mortality, insurance status, length of stay, zip code of residence, location of shooting, hospital charges, and recidivism for firearm injury, police officer-related interactions, or violence-related events were reviewed and ***:There were 585 patient charts reviewed over the 10-year period. The rate of pediatric firearm injuries increased by almost 5 folds and fatality rates tripled from 2013 to 2022. The victims were predominantly male (82.9%), black (75.3), non-Hispanic (88.5%), and Medicaid holder/uninsured (86.3%). Assault accounted for 67% of all GSWs and 13.5% returned with an assault or violence-related concern;6.4% returned for a GSW-related injury over the study period. The rate of firearm injuries increased from 9.09 (per 100,000) pre-COVID to 17.93 (per 100,000) post-COVID with a rate of 16.74 (per 100,000) while in the peak of the ***:This level 1 trauma center has seen an overall increase in pediatric GSW injuries and fatalities in 10 years.

摘要： The interference between two 5:1 rectangular cylinders in tandem is strongly affected by the gap width, which is relevant to parallel bridge decks and adjacent buildings. In the present study, three-dimensional large-eddy simulations are conducted to investigate the gap-width dependence of surface-flow and near-wake flow statistics, focusing on the mean velocity and Reynolds-stress distributions. Three gap widths are considered: G = 2D, 6D and 10D, where D is the cylinder height. The results show a transition of the overall flow structure from a reattachment pattern at G = 2D to a co-shedding pattern for G >= 6D. In addition to the global pattern transition, detailed surface-flow and near-wake statistics are presented to characterize the gap-width effects. For the upstream cylinder, the surface-flow structures and the Reynolds-stress features remain nearly unchanged with G, indicating weak sensitivity to gap width. In contrast, the downstream cylinder exhibits pronounced gap-width dependence: as G increases, a more developed recirculation bubble forms and flow recovery becomes faster, as evidenced by changes in the statistical distributions and surface-flow thickness. In the gap region, the mean velocity recovers more rapidly with increasing G, while the Reynolds-stress levels are reduced, indicating weakened turbulent activity sustained by the gap interactions. The Reynolds-stress distributions behind the downstream cylinder further reveal the effects of gap width on wake turbulence. These findings provide quantitative evidence of how gap width modifies surface-flow development and near-wake turbulence of tandem 5:1 rectangular cylinders.

关键词： Miscarriage   Placenta formation disorder   Implantation disorder   Arrest of villous maturation   Circulation disorder   Miscarriage   Placenta formation disorder   Implantation disorder   Arrest of villous maturation   Circulation disorder  

摘要： In 2025, the S2k guideline on early pregnancy loss in the first trimester was published. This guideline covers disrupted early pregnancy and pregnancies of unclear localization resulting in miscarriage, their etiology and risk factors, clinical diagnosis and patient care, as well as pathomorphological diagnostic criteria and recommendations for the macroscopic handling of the abortion tissue and its microscopic processing. In addition to possible causes, the aspects that are important for pathomorphological diagnosis are presented, and the diagnostic criteria mentioned in the guideline are summarized in tables and illustrated with images.

关键词： air sampling   digital PCR   EHV-1   EHV-4   horse   surveillance  

摘要： Background Equid alphaherpesvirus 1 (EHV-1) remains a major concern for the equine industry, with recent outbreaks at international equestrian events highlighting the need for improved surveillance during *** To investigate EHV-1 and -4 presence in shared airspaces and environmental surfaces in direct contact with horses at international equestrian events;and to evaluate air sampling as a surveillance alternative to individual horse *** Design Cross-sectional field *** Air (37) and surface samples (205) were collected from temporary stabling facilities across six events in Spain and 2 in the United States at different seasons over 10 months. Viral DNA (genomic copies) was measured and quantified by quantitative and digital PCR. During all the Spanish events, we sampled the air twice, early evening and *** EHV-1 was frequently detected in the air in 20/28 samples in Spain, in all 3 samples from Florida and in 3/6 samples from Kentucky. Surface samples were positive 15.6% in Spain, 26.3% in Florida and 0.0% in Kentucky. EHV-4 was found in air samples at rates of 12/28 in Spain, 5/6 in Kentucky and 0/3 in Florida, with surface detection of 1.6% in Spain and 7% in Kentucky. No significant differences were observed between daytime (high activity) and nighttime (low activity) airborne viral loads, suggesting that daytime horse movement and management practices had minimal impact on detection levels in our study. A positive correlation (Cohen's K = 0.401) and moderate agreement between surface and air positivity for EHV-1 emphasised the potential of air sampling as a non-invasive, cohort-based surveillance *** Limitations Virus isolation was not used;only molecular detection was employed, which limits conclusions about transmission *** These findings underscore the utility of air sampling for early EHV-1 detection at mass gatherings;although further validation is needed to connect genomic detection to act

摘要： Background:Individuals with neurofibromatosis type 1 (NF1) have a 10% lifetime risk of developing malignant peripheral nerve sheath tumors (MPNSTs). The majority of NF1-associated MPNSTs arise from preexisting plexiform neurofibromas (PNFs). The PNF subtypes susceptible to malignant transformation remain ***:This retrospective study included patients with head and neck PNFs who underwent surgical treatment at Shanghai Ninth People's Hospital from June of 2012 through July of 2023. Logistic regression analyses were conducted to assess risk factors for malignant transformation. Cox proportional hazards regression was used to evaluate the potential effects of variables on time to malignant ***:A total of 19 (4%) of the 470 PNFs underwent malignant transformation. Deep or proximal PNFs involving cranial nerve ganglia were significantly associated with an increased risk of malignant transformation (adjusted odds ratio, 3.10 [95% CI, 1.07 to 9.00]);tumor morphology, relationship to adjacent tissues, and demographic factors were not significantly associated with malignant transformation. Ganglion involvement significantly accelerated the time to malignant transformation by 36% (hazard ratio, 7.20 [95% CI, 2.33 to 22.28]).Conclusions:Involvement of cranial nerve ganglion is an independent risk factor for malignant transformation of head and neck PNFs. Patients with this high-risk profile require closer surveillance for malignancies and proactive management of suspicious lesions.

关键词： Experimental animal model   HIF-1 alpha   Ischemia-reperfusion injury   NF-kappa B   Nrf2   Oxidative stress   Transcription factors  

摘要： Objective(s): This study aimed to investigate the potential protective roles of monomethyl fumarate (MMF) and nifedipine (NF) against ovarian ischemia-reperfusion (I/R) injury in rats, with a particular focus on the contribution of oxidative stress-sensitive transcription factors HIF-1 alpha, NF-kappa B, and Nrf2. Materials and Methods: A rat model of ovarian I/R injury was established using 3-hr ischemia followed by 24-hour reperfusion. Ovarian hormone secretion capacity, oxidative stress-related biomolecular alterations, and apoptosis activation were analyzed using ELISA. Histopathological damage and apoptotic cell status were evaluated by hematoxylin-eosin (H&E) and immunohistochemical (IHC) staining. Expression levels of HIF-1 alpha, NF-kappa B, Nrf2, and related downstream genes were determined using RT-qPCR. Results: I/R significantly altered the expression of oxidative stress-associated transcription factors and their downstream targets compared with ischemia alone (P<0.05). Combined administration of MMF and NF restored serum AMH and E2 levels toward control values and reduced tissue oxidative stress markers (TOS and MDA). Gene expression of pro-apoptotic (BAX, BECLIN-1) and stress-related (HIF1 alpha, NF-kappa B, Nrf2) molecules improved under MMF and NF treatments. The combined therapy showed the most effective reduction in oxidative stress-induced molecular and histological alterations. Conclusion: MMF and NF exerted protective effects against ovarian I/R injury by modulating oxidative stress and apoptosis. These findings suggest that the coordinated regulation of HIF-1 alpha, NF-kappa B, and Nrf2 pathways may play a pivotal role in reducing reperfusion-related ovarian tissue damage.