The Portable Life Support System(PLSS),serving as a core component of the Extravehicular Activity spacesuit,must balance the requirements of life support protection and lightweight design.This study proposes a sandwich structure design based on Carbon Fiber Reinforced Polymer and validates the structural reliability of the composite backpack under launch/return segment overloads and space collision conditions through multi-scenario mechanical simulations.Simulation results demonstrate that the design achieves maximum deformations of 0.372 mm(mounting plate)under 6 g acceleration and 7.4 mm(skeleton)under 0.97 MPa impact loading,satisfying structural integrity requirements under extreme loads.The composite backpack manufactured by the autoclave molding process has passed the impact protection test under load conditions,verifying the manufacturing feasibility of the composite PLSS.This research provides a technically reliable pathway for lightweight design of EVA spacesuit structures by using composite materials,offering practical engineering value.

Objective To observe the effect of a Jianpi Huayu Jiedu formula on the NLRP3-mediated pyroptosis pathway in gastric precancerous lesion(GPL)associated with Helicobacter pylori(Hp)infection.Methods A GPL mouse model was prepared using Hp suspension gavage combined with Atp4a gene-deficient mice.The Jianpi Huayu Jiedu formula was administered as an intervention.Gastric mucosal tissue pathological damage was observed using hematoxylin and eosin(HE)staining.The presence of intestinal metaplasia(IM)was assessed using Alcian Blue-Periodic Acid Schiff(AB-PAS)staining.Ultrastructural changes in cell organelles were observed using transmission electron microscopy.Enzyme-linked immunosorbent assay(ELISA)was used to measure levels of gastrin-17(G-17),pepsinogen I(PGI),and proinflammatory cytokines IL-1β and IL-18.The expression of molecules related to the pyroptosis pathway was detected using Western blot and real-time quantitative PCR(RT-qPCR).Results Compared to the control group,Hp-related GPL mice exhibited gastric mucosal atrophy accompanied by IM and dysplasia.Damage to mitochondria and endoplasmic reticulum in parietal cells was observed.Levels of G-17,PGI,and proinflammatory cytokines IL-1β and IL-18 were elevated.The expression of molecules related to the pyroptosis pathway was increased.The Jianpi Huayu Jiedu formula significantly reduced gastric mucosal tissue pathological damage in GPL mice,decreased G-17 and PGI levels,mitigated inflammatory responses,and downregulated the expression of molecules related to the pyroptosis pathway.Conclusion The Jianpi Huayu Jiedu formula may exert its effects by inhibiting the NLRP3-mediated pyroptosis signaling pathway,thereby alleviating or even reversing the pathological damage of gastric mucosa in Hp-related GPL.

Objective To observe the effect of a Jianpi Huayu Jiedu formula on the NLRP3-mediated pyroptosis pathway in gastric precancerous lesion(GPL)associated with Helicobacter pylori(Hp)infection.Methods A GPL mouse model was prepared using Hp suspension gavage combined with Atp4a gene-deficient mice.The Jianpi Huayu Jiedu formula was administered as an intervention.Gastric mucosal tissue pathological damage was observed using hematoxylin and eosin(HE)staining.The presence of intestinal metaplasia(IM)was assessed using Alcian Blue-Periodic Acid Schiff(AB-PAS)staining.Ultrastructural changes in cell organelles were observed using transmission electron microscopy.Enzyme-linked immunosorbent assay(ELISA)was used to measure levels of gastrin-17(G-17),pepsinogen I(PGI),and proinflammatory cytokines IL-1β and IL-18.The expression of molecules related to the pyroptosis pathway was detected using Western blot and real-time quantitative PCR(RT-qPCR).Results Compared to the control group,Hp-related GPL mice exhibited gastric mucosal atrophy accompanied by IM and dysplasia.Damage to mitochondria and endoplasmic reticulum in parietal cells was observed.Levels of G-17,PGI,and proinflammatory cytokines IL-1β and IL-18 were elevated.The expression of molecules related to the pyroptosis pathway was increased.The Jianpi Huayu Jiedu formula significantly reduced gastric mucosal tissue pathological damage in GPL mice,decreased G-17 and PGI levels,mitigated inflammatory responses,and downregulated the expression of molecules related to the pyroptosis pathway.Conclusion The Jianpi Huayu Jiedu formula may exert its effects by inhibiting the NLRP3-mediated pyroptosis signaling pathway,thereby alleviating or even reversing the pathological damage of gastric mucosa in Hp-related GPL.

BACKGROUND:Among the pathogenic factors of cervical spondylosis,herniation of the intervertebral disc,dislocation of the facet joint and the stenosis of the intervertebral foramen are important factors leading to symptoms in patients.Moreover,inappropriate manipulation may aggravate the possibility of cervical disc rupture,leading to exacerbation of symptoms in patients. OBJECTIVE:To compare the effect between sagittal cervical manipulation and traditional cervical rotation manipulation on the area of the intervertebral disc,facet joint and intervertebral foramen at the operative segment by the finite element analysis. METHODS:The neck CT data of a male volunteer with a normal neck were selected and imported into Mimics 17.0 three-dimensional reconstruction software.Geo-magic Studio 12.0,Solidworks 2017 and Ansys Workbench 17.0 software were used for the construction of the finite element model of cervical vertebrae(C3-6)including intervertebral disc and articular cartilage.The lower end plate of the C5 vertebral body was fixed.A uniformly distributed vertical downward 50 N load was applied on the upper surface of the upper vertebral body(C3).The stress,deformation and deformation direction of the C4-5 intervertebral disc,joint capsule stress,the displacement of facet joints and the area of bilateral intervertebral foramen were compared between sagittal cervical manipulation and traditional rotation reduction. RESULTS AND CONCLUSION:(1)When using the rotation technique,the maximum normal equivalent stress(von Mises stress)of the C4-5 disc was 8.06 MPa;the total deformation was 1.05 mm,and the fiber ring expanded to the left and outside.When using the sagittal tip lifting technique,the maximum normal equivalent stress(von Mises stress)of the C4-5 disc was 2.60 MPa;the total deformation was 0.90 mm,and the fiber ring expanded to the left and back.Compared with the rotation technique,the pressure of the cervical manipulation technique on the disc was less(about 32.3%of the rotation technique),and the deformation degree of the disc was also light(about 85.7%of the rotation technique).(2)When the rotation technique was used,the maximum stresses of the left and right articular capsule ligaments were 0.37 MPa and 1.69 MPa,respectively.The overall displacement of the facet joint was 2.21 mm.The area of the right intervertebral foramen decreased by about 3.8%and the area of the left intervertebral foramen increased by about 0.9%.When the sagittal end lifting manipulation was performed,the maximum stresses of the left and right articular capsule ligaments were 0.27 MPa and 1.70 MPa,respectively;the overall displacement of the facet joint was 1.63 mm;the area of the right intervertebral foramen increased by about 2.6%,and the area of the left intervertebral foramen decreased by about 0.9%.Compared with rotation manipulation,sagittal end lifting manipulation had fewer changes in the displacement of facet joint,joint capsule stress and intervertebral foramen area,so it was safer to operate.(3)In conclusion,compared with cervical rotation manipulation,sagittal end lifting manipulation has fewer changes in facet joint displacement,intervertebral disc stress/deformation degree,joint capsule stress,and foraminal area.In clinical practice,more appropriate manipulation should be selected based on biomechanical results after an accurate assessment of patients'conditions.

Objective:To analyze the correlation between body mass index (BMI) and lung function in patients with bronchial asthma (asthma).Methods:This study was a retrospective study. A total of 828 patients with asthma were included from March 2013 to November 2022 in the first affiliated Hospital of Guangxi Medical University, including 292 males and 536 females, aged 21-82 years, with a median age of 47 years. According to BMI, these asthma patients were divided into high BMI group (BMI≥24 kg/m 2), normal BMI group (18.5 kg/m 2≤BMI<24 kg/m 2) and low BMI group (BMI<18.5 kg/m 2). Forced vital capacity (FVC), forced expiratory volume in first second (FEV 1), FEV 1/FVC, maximum mid-expiratory flow (MMEF), forced expiratory flow at 25%, 50% and 75% of FVC (FEF 25%, FEF 50%, FEF 75%), peak expiratory flow (PEF), absolute increases in measured values of FVC and FEV 1 and percentage increases in FVC%pred (“%pred” represents the percentage of related indicators to expected value) and FEV 1%pred after inhalation of bronchodilator (salbutamol) were measured by pulmonary function meter. The correlation between BMI and the above indexes was analyzed. Results:In the high BMI group, FEV 1%pred, MMEF, FEF 25%, FEF 50% and FEF 75% were significantly lower than those in the normal BMI group and the low BMI group (all P<0.05), FVC% pred was significantly lower than those in the normal BMI group( P<0.05), and the percentage increase of FEV 1%pred was significantly lower than those in low BMI group ( P<0.05). FVC% pred in the normal BMI group was significantly higher than that in the low BMI group ( P<0.05). In male patients, BMI was negatively correlated with the absolute increase of FEV 1 ( r=-0.148, P<0.05); In female patients, BMI was negatively correlated with FEV 1%, FEV 1/FVC, MMEF, FEF 25%, FEF 50%, FEF 75% and the percentage increase of FEV 1%pred ( r=-0.124, -0.127, -0.165, -0.138, -0.156, -0.162, -0.106, all P<0.05). Conclusion:There is a significant correlation between BMI and lung function in patients with asthma, and the lung function in patients with high BMI is relatively worse; and in female patients, the effect of BMI on lung function is more significant; the increase of BMI can lead to the decrease of lung function and airway reversibility, suggesting that attention should be paid to the management of BMI in asthma management.

OBJECTIVE To explore the the reg ulation of intestinal flora and effects of Qingjie huagong decoction on intestinal mucosal barrier in severe acute pancreatitis （SAP）mode rats . METHODS SAP rat model was induced by intraperitoneal injection of caerulein and lipopolysaccharide.The survival state of rats in each group were observed.The levels of serum amylase ，interleukin 10（IL-10），IL-18 and IL- 1β in serum were all detected. The pathological changes of pancreatic and small intestinal tissue were observed. The expressions of Occludin，ZO-1 and HMGB1 were detected in small intestinal tissue of rats. The structure and relative abundance of intestinal microflora in rats were detected by 16S rRNA high throughput sequencing. RESULTS After the intervention of Qingjie huagong decoction ，abdominal distension symptoms of SAP model rats were significantly relieved ，and their mental state recovered better ；the levels of serum amylase and IL- 18 in serum were decreased significantly （P＜0.05），while the level of IL- 10 was increased significantly （P＜0.05）. The necrotic area of pancreatic tissue and the infiltration of inflammatory cells were reduced ， the degree of intestinal epithelial cell structural disorder was alleviated ，and the shedding of intestinal mucosal epithelium was reduced.The protein expression of HMGB 1 in small intestinal tissue was decreased significantly （P＜0.05），and the protein expression of Occludin and ZO- 1 were increased significantly . Results of 16S rRNA high throughput sequencing showed that Qingjie huagong decoction could increased the relative abundance of probiotics such as Bacteroidea and Lactobacillus in rat intestine ，reduced the colonization of harmful bacteria such as Firmicutes. CONCLUSIONS Qingjie huagong decoction can improve the intestinal barrier by up-regulating the expression of Occludin and ZO- 1 in small intestinal tissue and down-regulating the protein expression of HMGB 1. It can also adjust the relative abundances of different flora to protect the intestinal tract.

In the study of embryo development process, the morphological features at different stages are essential to evaluate developmental competence of the embryo, which can be used to optimize and improve the system for
Blastocyst ; Embryo Culture Techniques ; Embryonic Development ; Fertilization in Vitro

Objective: To describe the secular trend of BMI and its consistency with self-rated BMI status in Chinese children and adolescents, and to further investigate the related factors affecting self-rated BMI,so as to provide a scientific reference for interventional measures. Methods: A total of 6 238 children and adolescents aged 6-18 years were selected according to date from Chinese Health and Nutrition Svrvey during 2000-2015 and the criteria from National Health Commission of China.The Lambda-Mu-Sigma method(LMS) and Kappa consistency test were, respectively, applied to describe the percentiles for BMI and its agreement with self-rated BMI status. Multinomial Logistic model was used to assess the related factors influencing self-rated BMI status. Results: P50 and P85 percentiles showed an increasing trend, especially the increase of high percentile of BMI. Regardless of age and sex, the measured and self-rated BMI showed low agreement. More than 50% of over-weighted or underweighted children perceived themselves as normal-weight, and about 1/4 of normal weight students misclassified themselves as abnormal in weight. Urban boys were more likely to evaluate themselves as underweight [OR(95%CI) =1.43(1.18-1.73)]. Boys who favored popular showed[OR(95%CI)=1.80(1.23-2.55) and cartoon [OR (95%CI) =1.39(1.00-1.96)] were more likely to consider themselves as overweight. Girls in the older age group [OR (95%CI)=2.74(2.08-3.61)] and urban [1.53(1.21-1.94)] who favored popular programs [OR(95%CI) =1.74(1.27-2.38)] were more likely to perceived themselves as overweight. But girls who like anime/cartoons were more likely to think they were underweight [OR(95%CI)=1.78(1.33-2.40)]. Conclusion The trend of BMI has shown an increasing trend in the past decade and it demonstrated a large bias with perceived BMI. Age, area and type of video were significant factors that influenced the self-rated BMI status.