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Supernova (SN) 2023ixf was discovered on 2023 May 19. The host galaxy, M101, was observed by the Hobby–Eberly Telescope Dark Energy Experiment collaboration over the period 2020 April 30–2020 July 10, using the Visible Integral-field Replicable Unit Spectrograph (3470 ≲λ≲ 5540 Å) on the 10 m Hobby–Eberly Telescope. The fiber filling factor within ±30″ of SN 2023ixf is 80% with a spatial resolution of 1″. Ther< 5.″5 surroundings are 100% covered. This allows us to analyze the spatially resolved preexplosion local environments of SN 2023ixf with nebular emission lines. The two-dimensional maps of the extinction and the star formation rate (SFR) surface density (Σ_SFR) show weak increasing trends in the radial distributions within ther< 5.″5 regions, suggesting lower values of extinction and SFR in the vicinity of the progenitor of SN 2023ixf. The median extinction and that of the surface density of SFR withinr< 3″ areE(B−V) = 0.06 ± 0.14, and${\mathrm{\Sigma }}_{\mathrm{SFR}}={10}^{-5.44\pm 0.66}{M}_{☉}{\mathrm{yr}}^{-1}{\mathrm{arcsec}}^{-2}.$There is no significant change in extinction before and after the explosion. The gas metallicity does not change significantly with the separation from SN 2023ixf. The metal-rich branch of theR₂₃calculations indicates that the gas metallicity around SN 2023ixf is similar to the solar metallicity (∼Z_☉). The archival deep images from the Canada–France–Hawaii Telescope Legacy Survey (CFHTLS) show a clear detection of the progenitor of SN 2023ixf in thezband at 22.778 ± 0.063 mag, but nondetections in the remaining four bands of CFHTLS (u,g,r,i). The results suggest a massive progenitor of ≈22M_☉.

 

Meniscal tears are associated with a high risk of osteoarthritis but currently have no disease-modifying therapies. Using a Gli1 reporter line, we found that Gli1 + cells contribute to the development of meniscus horns from 2 weeks of age. In adult mice, Gli1 + cells resided at the superficial layer of meniscus and expressed known mesenchymal progenitor markers. In culture, meniscal Gli1 + cells possessed high progenitor activities under the control of Hh signal. Meniscus injury at the anterior horn induced a quick expansion of Gli1-lineage cells. Normally, meniscal tissue healed slowly, leading to cartilage degeneration. Ablation of Gli1 + cells further hindered this repair process. Strikingly, intra-articular injection of Gli1 + meniscal cells or an Hh agonist right after injury accelerated the bridging of the interrupted ends and attenuated signs of osteoarthritis. Taken together, our work identified a novel progenitor population in meniscus and proposes a new treatment for repairing injured meniscus and preventing osteoarthritis. 

Entinostat is an oral small molecule inhibitor of class I histone deacetylases (HDAC), which has not previously been evaluated in pediatrics. We conducted a phase I trial to determine the maximum tolerated dose/recommended phase 2 dose (MTD/RP2D), toxicity profile, pharmacokinetics (PK), and pharmacodynamics (PD) of entinostat in children with relapsed or refractory solid tumors including central nervous system (CNS) malignancies.

A rolling six dose escalation design evaluated two dose levels. Entinostat oral tablet formulation was administered once per week, four doses per 28‐day cycle. PK and PD studies were performed.

Twenty‐one eligible patients’ median (range) age was 14 years (6‐20). Six subjects were treated at 3 mg/m²dose level and 15 were treated in 4 mg/m²dose level. The study included patients with CNS tumors (n = 12), sarcomas (n = 6), or other solid tumors (n = 3). Eight patients were not fully evaluable for toxicity due to progression of disease prior to receiving the required percentage of protocol therapy. No cycle one dose‐limiting toxicity (DLT) was observed at either dose level. A three‐fold higher area under the curve (AUC) was achieved in our cohort compared to adults using a similar dosing schedule. The PD studies showed increase in acetylated lysine in peripheral blood leukocytes at both doses.

Entinostat was well tolerated with no DLT observed. All patients experienced progression within the first two cycles, except one patient with ependymoma with stable disease. Based on PK and PD, the R2PD in pediatric patients with solid tumors is 4 mg/m²orally administered once weekly.

 

The physics potential of detecting⁸B solar neutrinos will be exploited at the Jiangmen Underground Neutrino Observatory (JUNO), in a model-independent manner by using three distinct channels of the charged current (CC), neutral current (NC), and elastic scattering (ES) interactions. Due to the largest-ever mass of¹³C nuclei in the liquid scintillator detectors and the expected low background level,⁸B solar neutrinos are observable in the CC and NC interactions on¹³C for the first time. By virtue of optimized event selections and muon veto strategies, backgrounds from the accidental coincidence, muon-induced isotopes, and external backgrounds can be greatly suppressed. Excellent signal-to-background ratios can be achieved in the CC, NC, and ES channels to guarantee the observation of the⁸B solar neutrinos. From the sensitivity studies performed in this work, we show that JUNO, with 10 yr of data, can reach the 1σprecision levels of 5%, 8%, and 20% for the⁸B neutrino flux,${\sin }^2{\theta }_{12}$, and$\mathrm{\Delta }{m}_{21}^2$, respectively. Probing the details of both solar physics and neutrino physics would be unique and helpful. In addition, when combined with the Sudbury Neutrino Observatory measurement, the world's best precision of 3% is expected for the measurement of the⁸B neutrino flux.

 

Premature restriction or closure of foramen ovale (FO) in otherwise structurally normal hearts may be associated with right ventricular dilation, tricuspid regurgitation, pericardial effusion, heart failure, even poor perinatal outcomes. Data about these rare conditions are lacking.

We retrospectively reviewed the echocardiographic records of 9704 fetuses seen from 2010 to 2014 in Beijing Anzhen Hospital, a regional and national referral center, to ascertain the presence of restriction or closure ofFO. We collected the fetal echocardiography and perinatal outcome data for this group of fetuses with restriction or closure ofFO.

In this large, single‐institution cohort (n = 9704), 6707 fetuses seen between 23 and 37 weeks of gestation had normal heart structures; of these, 60 (0.89%) had restrictiveFO(rFO) and 5 (0.07%) had closure ofFO(cFO). Fetal echocardiographic images showed right atrial dilation in 48 (73.84%), right ventricular dilation in 38 (58.46%), tricuspid regurgitation in 19 (29.23%), and pericardial effusion in 10 (15.38%). Also in this group, 50 (83.3%) withrFOand 4 (80.0%) withcFOhad follow‐up data. No prenatal deaths occurred in either therFOor thecFOgroup, but the neonatal mortality included 1 in therFOgroup and 2 in thecFOgroup.

PrematurerFO/cFOare rare in fetuses with otherwise structurally normal hearts. The fetal echocardiographic characteristics include right atrial and ventricular dilated, tricuspid regurgitation, and pericardial effusion. Most fetuses had a good outcome, although there was an association betweenrFO, especiallycFO, with neonatal morality and complications (prematurity, maternal preeclampsia and placental abruption, hydrops fetalis, and necrotizing enterocolitis with perforation).

 

The core-collapse supernova (CCSN) is considered one of the most energetic astrophysical events in the universe. The early and prompt detection of neutrinos before (pre-SN) and during the supernova (SN) burst presents a unique opportunity for multi-messenger observations of CCSN events. In this study, we describe the monitoring concept and present the sensitivity of the system to pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton liquid scintillator detector currently under construction in South China.The real-time monitoring system is designed to ensure both prompt alert speed and comprehensive coverage of progenitor stars. It incorporates prompt monitors on the electronic board as well as online monitors at the data acquisition stage.Assuming a false alert rate of 1 per year, this monitoring system exhibits sensitivity to pre-SN neutrinos up to a distance of approximately 1.6 (0.9) kiloparsecs and SN neutrinos up to about 370 (360) kiloparsecs for a progenitor mass of 30 solar masses, considering both normal and inverted mass ordering scenarios.The pointing ability of the CCSN is evaluated by analyzing the accumulated event anisotropy of inverse beta decay interactions from pre-SN or SN neutrinos. This, along with the early alert, can play a crucial role in facilitating follow-up multi-messenger observations of the next galactic or nearby extragalactic CCSN.