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Using observations from multi‐satellites at different altitudes, including the CHAllenging Minisatellite Payload (CHAMP), the Gravity Recovery and Climate Experiment, Swarm B, and Defense Meteorological Satellites Program F17, the ionospheric post‐midnight enhancement at mid‐latitudes and the associated inter‐hemispheric asymmetry during equinox are investigated in this study. During equinox months, the ionospheric electron density enhancement during post‐nighttime at mid‐latitudes is visible in both hemispheres, however, it is asymmetric between the Northern and Southern Hemispheres. At most longitudes, inter‐hemispheric asymmetry of Mid‐latitude Ionospheric Post‐midnight Enhancement (MIPE) reverses with altitudes, from a stronger electron density in the Northern Hemisphere at CHAMP altitude to a stronger electron density in the Southern Hemisphere at top ionosphere during equinox. The reversal altitude and reversal time have significant longitudinal differences. The effective ionospheric uplifting induced by the combination of neutral winds and geomagnetic field configuration is the main contribution to the asymmetry reversal of MIPE at lower altitudes, as shown in the simulations from the SAMI2 and HWM14 models. In comparison with that in the Southern Hemisphere, the stronger neutral winds in the Northern Hemisphere move the plasma along the geomagnetic field lines to a higher altitude with lower chemical recombination, resulting in the enhancement of electron density. Plain Language Summary: The mid‐latitude ionospheric post‐midnight enhancement is a phenomenon that the electron densities at mid‐latitudes are higher than that at low‐latitudes during post‐midnight. Recently, the mid‐latitude post‐midnight electron density bands during equinox months are found to have an inter‐hemispheric asymmetry and an altitudinal reversal at most longitudes. However, the potential physical mechanisms are poorly understood, which is key in the modeling and forecasting of near‐Earth space weather. Using simulation results from models, we found that neutral winds and geomagnetic field configuration are critical for the reversal of inter‐hemispheric asymmetry with altitude. Key Points: The mid‐latitude ionospheric post‐midnight enhancement exhibit significant inter‐hemispheric asymmetry during equinox months at various altitudes above F2‐peakAt most longitudes, the hemispheric asymmetry reversed with altitude and the reversal altitude shows significant longitudinal differencesThe effective ionospheric uplifting induced by neutral winds and geomagnetic field configuration is the key in the altitudinal reversal [ABSTRACT FROM AUTHOR]

Abstract The study of mechanical properties and failure mechanism of propellants under impact loads is crucial for analyzing structural integrity of propellant charges. An experimental investigation was conducted on NEPE propellant using a separated Hopkinson pressure bar to conduct high strain rate uniaxial impact tests. Deformation and failure processes of the propellant under impact conditions were recorded with a high-speed camera. The microscopic failure forms of the propellants were observed using a scanning electron microscope and an optical microscope. Stress-strain curves and high-speed images revealed that the damage behavior and failure mechanism of NEPE propellants are significantly influenced by strain rate. As the strain rate increases, there is a notable increase in the deformation degree of the propellant specimens, with a more pronounced shear effect. This leads to an earlier occurrence of failure and a more severe degree of failure. The predominant failure forms observed in NEPE propellants include transgranular failure, matrix tearing, and cavity merging. A nonlinear visco-hyperelastic constitutive model with damage at high strain rates was established to provide a precise account of the mechanical response of NEPE propellant under high strain rates.

Background The prevalence of overweight and obesity among children and adolescents is continuously rising. As countries have developed several school-based nutrition policies to control overweight and obesity, it is important to examine the effectiveness of nutrition policies. Objective To evaluate the effect of the centralized distribution of food material system on overweight and obesity rates among children and adolescents aged 6-15 years. Methods In April 2023, a total of 104 749 BMI data from sixteen schools aged 6 to 15 years (8 schools were included in the unified food distribution system and recorded as the unified distribution group, and 8 schools were not included in the unified food distribution and supply system and recorded as the non-unified distribution group) in Wuxi were retrospectively collected between 2017 and 2021. The data of physical examination was collected from Student Health Monitoring System in Jiangsu Province. The overweight and obesity epidemiologic trends among children and adolescents were analyzed from 2017 to 2021 in Wuxi, and the changes in BMI-Z scores and trends in overweight and obesity rates among children and adolescents were compared before and after the implementation of the centralized distribution of food material system by the Joinpoint regression and grey GM (1, 1) model. Results The prevalence of overweight and obesity among in children and adolescents aged 6-15 years was increasing from 2017 to 2021. The results of the Joinpoint regression analysis indicated that the prevalence of overweight (APC 1.8% vs 4.6%) and obesity (APC 6.9% vs 13.3%) among students included in the system exhibited a slower rate of increase than among those not included. The disparity in the increase of BMI-Z scores among students included in the system and those not included changed from -0.055 (95%CI=-0.108--0.002) to -0.195 (95%CI=-0.246--0.145) before and after the implementation of the system. The results of grey GM (1, 1) model showed that the incidence rate of overweight among children and adolescents in Wuxi in 2022, 2023 and 2024 was 22.02%, 22.39% and 22.77% respectively, with the incidence rate of overweight being 17.02%, 18.50% and 20.12% respectively. Conclusion The increasing trend in the prevalence of overweight and obesity, as well as the increase in BMI-Z scores among children and adolescents, has slowed down after the implementation of the centralized distribution of food material system. The system may be an effective method of improving the nutritional status of children and adolescents. Therefore, it is recommended that the centralized distribution of food material system still needs to be implemented and the monitoring area needs to be expanded.

BackgroundsInsomnia is frequent in schizophrenia and is found to be negatively affected by stressful life events， psychotic symptoms and depressive disorder， while the relationship among the four remains understudied in community-dwelling patients with schizophrenia.ObjectiveTo analyze the effect of stressful life events on insomnia in community-dwelling patients with schizophrenia， and to explore the mediation effect of psychotic symptoms and depression， so as to provide references for the intervention of insomnia in community-dwelling patients with schizophrenia.MethodsFrom April to June 2023， a sample of 1 105 patients with schizophrenia attending 48 community health centers in Chengdu， Sichuan province and fulfilling the International Classification of Diseases， tenth edition （ICD-10） diagnostic criteria were included. All subjects were assessed using Stressful Life Event Scale （SLEs）， Athens Insomnia Scale （AIS）， Psychosis Screening Questionnaire （PSQ）， and Patient Health Questionnaire Depression Scale （PHQ-9）. Spearman correlation analysis was used to determine the correlation among the scales. Then the mediation model was constructed using Smart PLS 4.0， and tested with partial least squares algorithm and Bootstrap techniques.Results332 patients （30.05%） with community schizophrenia were found to have insomnia. AIS scores in patients with schizophrenia were positively correlated with the scores on SLEs， PSQ and PHQ-9 （r=0.165， 0.322， 0.554， P

Abstract Nasopharyngeal carcinoma (NPC) presents a significant medical challenge due to its high incidence rate and poor prognosis, which are attributed primarily to tumor metastasis and drug resistance. Sine oculis homeobox homolog 1 (SIX1) has been identified as a crucial target for cancer treatment. However, its role in NPC remains incompletely understood. This study investigated the mechanisms by which the degradation of the SIX1 protein, which is mediated by ubiquitin, affects the malignant characteristics of NPC throughout the cell cycle. Our findings reveal that reduced expression of the itchy E3 ubiquitin ligase E3 (ITCH) in NPC impedes the degradation of the SIX1 protein, leading to enhance oncogenic properties. Knockdown experiments which SIX1 was inhibited demonstrated a decrease in the proliferation, migration, and invasion of NPC cell lines, whereas overexpression of SIX1 yielded the opposite effects. Further experimental validation revealed that SIX1 promotes NPC progression via the cell division cycle 27 (CDC27)/cyclin B1 axis. These findings provide valuable insights into potential therapeutic targets and prognostic indicators for NPC treatment, emphasizing the ITCH/SIX1/CDC27/cyclin B1 axis as a promising target for novel therapies.

Abstract Background Depression and chronic constipation often co-occur, but the reciprocal influence between the two remains unclear. The purpose of this study is to explore the potential association between depression and chronic constipation. Methods This study initially utilized data from National Health and Nutrition Examination Survey (NHANES) 2005–2010 to explore the correlation between depression scores and chronic constipation, assessing the non-linear relationship between the two. Subsequently, we conducted a two-sample Mendelian randomization (MR) analysis to evaluate the causal relationship between depression and major depression with chronic constipation. The Inverse Variance Weighting (IVW) method served as the primary reference, supplemented by sensitivity tests. Finally, a reverse MR analysis was performed to assess the presence of any reverse causation. The STROBE-MR checklist for the reporting of MR studies was used in this study. Results In the NHANES analysis, survey-weighted logistic regression revealed a significantly positive correlation between depression scores and chronic constipation (OR = 1.04, 95% CI = 1.02–1.07, p = 0.002), even after adjusting for the included covariates. The nonlinear analysis using Restricted Cubic Splines (RCS) enhanced the robustness of the association (P-non-liner = 0.01). The MR analysis also confirmed the causal relationship between depression (OR = 11.43, 95% CI = 1.85–70.67, p = 0.008) and major depression (OR = 1.12, 95% CI = 1.03–1.22, p = 0.007) with chronic constipation, passing rigorous sensitivity tests. No evidence of reverse causation was observed in the reverse MR analysis (P > 0.05). Conclusions Depression is positively correlated with the risk of chronic constipation. Therefore, enhancing attention to chronic constipation in patients with depression may be effective in clinical practice.

Abstract Eating disorders (EDs), including anorexia nervosa (AN), bulimia nervosa (BN), binge-eating disorder (BED), and pica, are psychobehavioral conditions characterized by abnormal eating behaviors and an excessive preoccupation with weight and body shape. This review examines changes in brain regions and functional connectivity in ED patients over the past decade (2013–2023) using resting-state functional magnetic resonance imaging (rs-fMRI). Key findings highlight alterations in brain networks such as the default mode network (DMN), central executive network (CEN), and emotion regulation network (ERN). In individuals with AN, there is reduced functional connectivity in areas associated with facial information processing and social cognition, alongside increased connectivity in regions linked to sensory stimulation, aesthetic judgment, and social anxiety. Conversely, BED patients show diminished connectivity in the dorsal anterior cingulate cortex within the salience network and increased connectivity in the posterior cingulate cortex and medial prefrontal cortex within the DMN. These findings suggest that rs-fMRI could serve as a valuable biomarker for assessing brain function and predicting treatment outcomes in EDs, paving the way for personalized therapeutic strategies.

Abstract Background Hypoxia plays an important role in the chemotherapy resistance of nasopharyngeal carcinoma (NPC). Ferroptosis is a newly discovered form of programmed cell death and ferroptosis inducers showed promising therapeutic effects in some cancers. However, the sensibility of NPC cells to ferroptosis under the hypoxic microenvironment is still unclear, and this study was designed to clarify it. Methods NPC cells, treated with erastin, were placed in a normoxia or hypoxic environment (5% CO2, 94% N2 and 1% O2) at 37℃for 24 h. After exposed to hypoxia, ferroptosis-associated phenotypes were detected by CCK8, MDA, GSH, lipid ROS and Fe. The gene expression profiles of head and neck squamous cell carcinoma (HNSCC) tissues were downloaded from the TCGA database to screen construction molecule. BAP1 was screened out and its functions on erastin-induced ferroptosis in NPC cells were detected by knockdown of BAP1. Luciferase reporter assay and co-IP experiment were performed to explore the molecular mechanism. Finally, the tumour xenograft model was applied to further verify these results in vivo. Results CCK8 assay showed that IC50 of NPC cells treated with erastin under hypoxia was significantly lower than that under normoxia. Hypoxia significantly increased the levels of lipid ROS and MDA, and decreased GSH content induced by erastin. A prognostic risk model for HNSCC with six ferroptosis-related genes was constructed and validated based on TCGA database. BAP1 was significantly up-regulated under hypoxia, and luciferase reporter assay showed that HIF-1α was an upstream transcription regulator of BAP1. Knockdown of BAP1 in NPC cells significantly increased the IC50 value of erastin under hypoxia and significantly ameliorated erastin-induced ferroptosis under hypoxia in aspect of lipid ROS, MDA content and GSH. Co-IP results showed that BAP1 mediated deubiquitination of H2A and decreased SLC7A11 expression. Finally, knockdown of BAP1 reduced sensitivity to erastin-induced ferroptosis in a tumour xenograft model. And the level of H2A was significantly decreased in xenograft tumors of BAP1 knockdown cells. Conclusion Hypoxia-induced BAP1 enhances erastin-induced ferroptosis in NPC by stabilizing H2A. Ferroptosis inducers targeting BAP1 may be an effective way to improve chemotherapy resistance in NPC, especially in the hypoxic microenvironment. Graphical Abstract

In this paper, we investigated the potential use of a new organic-inorganic hybrid crystal structure based on KNO3 in ignition compositions. H2dabco[K(NO3)3] (DAN-2) with organic-inorganic hybrid crystal structure is synthesized through intermolecular assembly technology. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to detect the crystal morphology, structure and molecular structure of DAN-2, which has a regular cubic structure. Experimental data were obtained using thermogravimetric/differential scanning calorimetry (TG-DSC), closed bomb test and high-speed photography, which were then used to study and analyze the thermal decomposition properties and combustion properties of DAN-2. The initial thermal decomposition temperature of DAN-2 was low (194 °C) and the activation energy of the thermal decomposition was 154 kJ/mol. Possible thermal decomposition mechanisms are further discussed and proposed. This research pushed forward the application of organic-inorganic hybrid crystal structure oxidant DAN-2 in ignition system.