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We report a photometric and asteroseismic analysis of KIC 3868420, a newly identified high-amplitude δ Scuti–γ Doradus hybrid star located in the Hertzsprung gap—a short-lived and rarely observed post-main-sequence phase. Using 4 yr of Kepler long-cadence photometry, we detect 36 significant frequencies, including 11 independent modes spanning both low- and high-frequency regimes. Grid-based modeling with MESA and GYRE, including rotation, shows that five independent frequencies match a combination of radial p-modes and nonradial g-modes, supporting its hybrid nature. The best-fit models yield an evolved post-main-sequence star (M ∼ 2.26–2.30M⊙, R ∼ 4.41–4.43R⊙, and τ ∼ 5.4 × 108 yr), although degeneracies from rotation and unknown inclination preclude a unique solution. KIC 3868420 thus represents a rare example of a high-amplitude hybrid pulsator in the Hertzsprung gap, demonstrating that high-amplitude pulsation can coexist with mixed p-/g-mode behavior in a rapidly evolving star. This finding highlights the value of space-based photometry for identifying such rare objects.

Sepsis remains a major global concern and is associated with high mortality and morbidity despite improvements in its management. Markers currently in use have shortcomings such as a lack of specificity and failures in the early detection of sepsis. In this study, we aimed to identify key genes involved in the molecular mechanisms of sepsis and search for potential new biomarkers and treatment targets for sepsis using bioinformatics analyses. Three datasets (GSE95233, GSE57065, and GSE28750) associated with sepsis were downloaded from the public functional genomics data repository Gene Expression Omnibus. Differentially expressed genes (DEGs) were identified using R packages (Affy and limma). Functional enrichment of the DEGs was analyzed with the DAVID database. Protein-protein interaction networks were derived using the STRING database and visualized using Cytoscape software. Potential biomarker genes were analyzed using receiver operating characteristic (ROC) curves in the R package (pROC). The three datasets included 156 whole blood RNA samples from 89 sepsis patients and 67 healthy controls. Between the two groups, 568 DEGs were identified, among which 315 were upregulated and 253 were downregulated in the septic group. These genes were enriched for pathways mainly involved in the innate immune response, T-cell biology, antigen presentation, and natural killer cell function. ROC analyses identified nine genes—LRG1, ELANE, TP53, LCK, TBX21, ZAP70, CD247, ITK, and FYN—as potential new biomarkers for sepsis. Real-time PCR confirmed that the expression of seven of these genes was in accordance with the microarray results. This study revealed imbalanced immune responses at the transcriptomic level during early sepsis and identified nine genes as potential biomarkers for sepsis.

Background. Ferroptosis is a nonapoptotic form of programmed cell death, which may be related to the occurrence and development of sepsis-induced acute respiratory distress syndrome (ARDS)/acute lung injury (ALI). Mucin 1 (MUC1) is a kind of macromolecule transmembrane glycoprotein. Previous studies have shown that MUC1 could relieve ALI in sepsis and predict whether sepsis patients would develop into ARDS. However, the role of MUC1 in the ferroptosis of sepsis-induced ALI/ARDS remains unclear. Materials and Methods. Sera samples from 50 patients with sepsis/septic shock were used to detect iron metabolism-related markers. Western blot and qRT-PCR were conducted to detect the expression levels of ferroptosis-related genes. Enzyme-linked immunosorbent assay (ELISA) was performed to evaluate inflammatory factors. Transmission electron microscopy (TEM) was used to assess morphological changes of cells. Results. The results showed that the iron metabolism-related indicators in sepsis-induced ARDS patients changed significantly, suggesting the iron metabolism disorder. The expression levels of ferroptosis-related genes in lung tissues of sepsis had marked changes, and the lipid peroxidation levels increased, while Ferrostatin-1 (Fer-1) could reverse the above results, which confirmed the occurrence of ferroptosis. In terms of mechanism studies, inhibition of MUC1 dimerization could increase the expression level of Keap1, reduce the phosphorylation level of GSK3β, inhibit the entry of Nrf2 into the nucleus, further inhibit the expression level of GPX4, enhance the lipid peroxidation level of lung tissues, trigger ferroptosis, and aggravate lung injury. Besides, inhibiting MUC1 reversed the alleviating effect of vitamin E on ALI caused by sepsis, increased the aggregation of inflammatory cells in lung tissues, and aggravated alveolar injury and edema. Conclusions. Our study was the first to explore the changes of iron metabolism indicators in ALI/ARDS of sepsis, clarify the important role of ferroptosis in ALI/ARDS induced by sepsis, and reveal the effects and specific mechanisms of MUC1 in regulating ferroptosis, as well as the sensitization on vitamin E.

In this paper, we present an analysis of the pulsating behavior of Kepler target KIC 9845907. Using the data from Kepler, we detected 85 significant frequencies, including the first overtone f 1 = 17.597 day−1 as the dominant frequency, the non-radial independent frequency f 3 = 31.428 day−1 (ℓ = 1), as well as two modulation terms f m1 = 0.065 day−1 and f m2 = 1.693 day−1. We found fourteen pairs of triplet structures with f m1 or f m2, four pairs of which can further form quintuplet structures. We note these are the most intriguing features discovered in this study and they were recognized for the first time in δ Scuti stars. We discussed several possible explanations, i.e., beating, the Blazhko effect, combination mode hypothesis, nonlinear mode coupling, large separation, and stellar rotational splitting for these equidistant structures. Our asteroseismic models indicate this modulation with f m1 might be related to the rotational splitting. The study of more δ Scuti stars with triplet and/or quintuplet structures using high-precision space photometry would be helpful to further explore its origin.

It has been reported that approximately 40% of ALI (acute lung injury) incidence resulted from sepsis. Paclitaxel, as a classic anti-cancer drug, plays an important role in the regulation of inflammation. However, we do not know whether it has a protective effect against CLP (cecal ligation and puncture)-induced septic ALI. Our study aims to illuminate the mitigative effects of paclitaxel on sepsis-induced ALI and its relevant mechanisms. The survival rates and organ injuries were used to evaluate the effects of paclitaxel on CLP mice. The levels of inflammatory cytokines were tested by ELISA. MUC1 siRNA pre-treatment was used to knockdown MUC1 expression in vitro. GO203 was used to inhibit the homodimerization of MUC1-C in vivo. The expression levels of MUC1, TLR 4 and p-NF-κB/p65 were detected by Western blot. Our results showed that paclitaxel improved the survival rates and ameliorated organ injuries especially lung injury in CLP-induced septic mice. These were accompanied by reduced inflammatory cytokines in sera and BALF (bronchoalveolar lavage fluid). We also found paclitaxel could attenuate TLR 4-NF-κB/p65 activation both in lung tissues of septic mice and LPS-stimulated lung type II epithelial cell line A549. At the upstream level, paclitaxel-upregulated expression levels of MUC1 in both in vivo and in vitro experiments. The inhibitory effects of paclitaxel on TLR 4-NF-κB/p65 activation were reversed in lung tissues of septic mice pre-treated with MUC1 inhibitor and in MUC1-knockdown A549 cells. Protection of paclitaxel on sepsis-induced ALI and decrease of inflammatory cytokines were also abolished by inhibition of MUC1. Collectively, these results indicated paclitaxel could significantly alleviate acute lung injury in CLP-induced septic mice and LPS-stimulated lung type II epithelial cell line A549 by activating MUC1 and suppressing TLR-4/NF-κB pathway.

The Yarkovsky effect causes the semimajor axis drift of near-Earth asteroids. The drift can be detected by a precise orbit determination process. Using the proposed algorithm, 2233 out of 27,078 near-Earth asteroids are chosen as the initial candidates. Out of these initial candidates, 769 have a measurable Yarkovsky effect with a signal-to-noise ratio (S/N) larger than 1, and 166 have a measurable Yarkovsky effect with an S/N larger than 3. The ratio between retrograde and prograde near-Earth asteroids is plotted with respect to their size. An average ratio of 2 is found for asteroids with an absolute magnitude between 14 and 21. The measurement work is carried out based on orbit determination software developed by the authors that considers a high-precision dynamical model.

We investigated the pulsating behavior of TIC 400562821 using high-precision observations from TESS. Fourier analysis of time-series data revealed three independent frequencies. The period ratios of F to F1 (0.774) and F to F2 (0.625), along with an amplitude change of approximately 0.1 mag, indicate that TIC 400562821 is a triple-mode High-Amplitude δ Scuti (HADS) star. Using the Best Parent Method and the Γ O functions, we identified that the harmonics and sum combination frequencies of F and F1 are caused by the nonlinear response of the stellar medium to pulsation. We also analyzed the amplitude variations of F, F1, and F2. Observational data over 76 days show stable amplitudes for these modes. However, Radial Stellar Pulsations modeling suggests that, over 10,000 cycles, the amplitude of F remains constant, while F1 gradually decreases and F2 approaches zero. This implies that TIC 400562821 may eventually evolve into a single-mode HADS star. Furthermore, asteroseismic modeling was performed, and several effects, such as the mixing-length parameter α MLT and nonadiabatic, were examined on this star. In view of the results by Daszyńska-Daszkiewicz et al. (i.e., α MLT < ∼1 for δ Scuti stars), TIC 400562821 is suggested to be more likely in the post-main-sequence stage, with mass M = 1.34–1.38 M ⊙ and metallicity Z = 0.007–0.008, but still warrants further study to ascertain its nature.

In this paper, we present a detailed analysis of the light variation of KIC 5623923 using high-precision time-series data from the Kepler mission. The analysis reveals this target is an eclipsing binary system with δ Scuti-type pulsations from the primary component, rather than from the secondary as previously reported. The frequency analysis of three short-cadence data reveals 41 significant frequencies, including the orbital frequency (forb = 0.827198 day−1) due to orbital motion from the binary system and the pulsational frequencies. Most of the pulsational signal lies in the frequency range of 20–32 day−1, with amplitude between 0.3 and 8.8 mmag, in which seven peaks are identified as “independent” modes. The strongest one (f3 = 28.499399 day−1) likely corresponds to a high-order radial mode. In other peaks (f7, f10, and f18), several pairs of multiplet structures centered on them are found. The fitting of spectral energy distribution using the collected photometry measurement of multiple bands reveals the effective temperatures of the primary and secondary components as 8348−225+230 K and 4753−229+237 K, respectively, which place the primary star in the classical pulsating instability zone. The characteristic light-curve morphology and short orbital period are consistent with a tidally locked system. Based on the characteristics of amplitude spectra of pulsating stars in close binaries, the analysis of the multiplet structures reveals that three independent frequencies (i.e., f7, f10, and f18) correspond to nonradial modes with l = 2, while the associated sidelobes are produced by the orbital motion. We highlight the potential of this method in future studies of pulsating binary stars.

In this paper, we analyze the light variation of KIC 8840638 using high-precision time-series data from the Kepler mission. The analysis reveals that this target is a new detached eclipsing binary system with a δ Scuti component, rather than a single δ Scuti star as previously known. The frequency analysis of short-cadence data reveals 95 significant frequencies, most of which lie in a frequency range of 23−32 day−1. Among them, seven independent frequencies are detected in the typical frequency range of δ Scuti stars, and they are identified as pressure modes. In addition, a possible large separation value of Δν = 36.5 ± 0.1 μHz is also detected with the Fourier transform (FT) and autocorrelation function (AC) analysis. The orbital frequency f orb (= 0.320008 day−1) and its harmonics are also detected directly in the frequency spectrum. The binary modelings derived from PHOEBE indicate that this binary system is in detached configurations with a mass ratio of q=0.33−0.04+0.06 , an inclination angle of 40.19−2.84+3.96 ​​​​​°. The derived parameters and binary evolutionary model suggest that the primary star is an object on the verge of leaving the main sequence with a temperature of ∼7600 K, while the secondary appears to be a cool component entering the giant branch with a temperature ∼3100 K lower than the primary. Moreover, this system may have undergone a mass ratio reversal, where the more massive star is the gainer component and the less massive one is the donor star.

Fluid balance in the early stages of severe acute pancreatitis (SAP) significantly impacts patient outcomes. This study aimed to identify the optimal fluid balance value affecting adverse outcomes in SAP patients to enhance fluid management. The study comprised two parts. Part 1 involved a retrospective review of 560 SAP patients at Ruijin Hospital (1996–2008) to determine the optimal fluid balance for in-hospital mortality using multivariable regression and ROC curve analysis. Part 2 prospectively examined 343 SAP patients in Emergency Intensive Care Unit at Ruijin Hospital (2020–2023) to validate findings regarding 30-day mortality and organ support. In Part 1, key independent risk factors for in-hospital mortality included age, weight, hypertension, APACHE II score, D0-D2/kg fluid balance, sugery and necrosis. The optimal predictive D0-D2/kg fluid balance value was found to be 48.4 ml/kg. In Part 2, exceeding this value indicated a higher risk for 30-day mortality (HR = 3.477) and increased need for mechanical ventilation (OR = 4.741) and blood purification (OR = 3.685). A D0-D2/kg fluid balance above 48.4 ml/kg correlates with poorer outcomes in SAP patients, providing guidance for clinicians in fluid management to improve prognosis.