Objective To investigate the effects of increasing the ejection seat backrest angle on the body pressure distribution of pilots of different body types,and to provide a basis for the design of ejection seats,flight training,and the development of strategies to alleviate muscle fatigue.Methods Male fighter pilots were divided into normal and overweight groups according to their body mass index(BMI),and a total of 40 pilots were tested for the distribution of sitting pressure under the two seat inclination angles of 20°and 33°by using the body pressure distribution measurement system.The effects of different seat inclination angles on sitting comfort were also analyzed.Results The pressure distributions of pilots with different body types were significantly different at different seat inclination angles.Compared with the 20°seat,the 33°seat condition had a larger cushion contact area[F(1,78)=40.281,P<0.001],a smaller average pressure and average pressure gradient[F(1,78)=32.030,P<0.001;F(1,78)=12.594,P<0.001],and significantly reduced average,maximum pressure,and maximal pressure gradients for the backrest[F(1,78)=10.516,P=0.002;F(1,78)=26.803,P<0.001;F(1,78)=4.918,P=0.029,respectively].In addition,overweight individuals with BMI had a notable increase in the cushion contact area[F(1,78)=21.038,P<0.001]and the backrest contact area[F(1,78)=8.301,P=0.005].No significant interaction was observed for angle and BMI.Conclusion An increased seat inclination angle results in a more uniform distribution of pressure across the human body,thereby increasing comfort.Moreover,the disparities in pressure and backrest distribution across disparate body types at varying seat angles provide a vital foundation for the optimized design of seating.

Objective To propose strategies for developing clinical predictive models,aiming to assist researchers in conducting standardized clinical prediction model studies.Methods Literature review was conducted to summarize the operational steps and content for developing clinical predictive models.Then,a methodological framework was summarized and refined through expert consultation.Results The 11-step methodological framework for developing clinical predictive models was obtained by synthesizing the experience of 456 clinical predictive modeling studies and expert consultation,and the details were analyzed and elaborated.Conclusions This study presents methodological strategies and recommendations for the development of clinical predictive models,intended to serve as a guide for researchers.

Objective:We try to screen out predictive indicators with higher value by analyzing the differences in clinical and laboratory indicators between severe fever with thrombocytopenia syndrome (SFTS) patients in the intensive care unit (ICU) group and non-ICU group.Methods:The clinical and laboratory index data of 69 SFTS patients diagnosed in the laboratory in a hospital from June to December 2019 were retrospectively collected. According to the clinical outcome of the patients, they were divided into ICU and non-ICU groups. The differences in clinical manifestations and laboratory indicators between the two groups were analyzed. The receiver operating characteristic curve (ROC) was used to screen the more valuable predictive indicators.Results:Compared with the non-ICU group, ICU group SFTS patients had significantly higher procalcitonin (PCT), C-reactive protein (CRP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), glutamyl transpeptidase (GGT), leucine aminopeptidase (LAP), glutamate dehydrogenase (GDH), adenosine deaminase (ADA), cystatin C (Cys C), α-hydroxybutyrate dehydrogenase (α-HBDH), creatine kinase (CK), lactate dehydrogenase (LDH) levels ( W=530.0, P=0.003; W=496.5, P=0.015; W=496.0, P=0.015; W=535.5, P=0.002; W=545.5, P=0.001; W=498.5, P=0.013; W=537.0, P=0.002; W=523.0, P=0.004; W=512.0, P=0.007; W=502.0, P=0.012; W=486.0, P=0.023; W=509.0, P=0.008; W=541.0, P=0.002) and significantly lower platelet count (PLT), indirect bilirubin (IBIL), albumin/globulin ratio(A/G) and superoxide dismutase (SOD) levels ( W=199.0, P=0.024; W=175.5.5, P=0.009; t=-2.9, P=0.004; W=209.5, P=0.036; t=-3.0, P=0.004). ROC result showed that ALP [area under the curve (AUC)=0.804, 95% confidence interval ( CI) (0.679~0.929)] and LDH [AUC=0.805, 95% CI (0.680~ 0.930)] have a higher value for predicting the risk of severe illness. Conclusions:Abnormal liver function, heart function, and renal function indicators in SFTS patients indicate that patients are at risk of exacerbation. Among them, ALP and LDH levels have higher predictive value for risk of severe disease, suggesting that the monitoring of patients with the above symptoms should be strengthened in the clinical nursing process.

Objective:To systematically review the effects of the traditional Chinese medicine compound based on astragalus and angelica on bone marrow suppression after chemotherapy.Methods:Randomized controlled trials (RCTs) about the traditional Chinese medicine compound based on astragalus and angelica for bone marrow suppression after chemotherapy for malignant tumors were retrieved from Cochrane Library, PubMed, Web of Science, CINAHL, OVID, SinoMed, CNKI, VIP, and Wanfang Databases. The search period was from the establishment of the database to September 2019. The literatures were screened and the data were extracted independently by two researchers and RevMan 5.3 was used for Meta-analysis.Results:Totally 15 RCTs were included, involving 1 019 patients. Meta-analysis results showed that there were statistically significant differences in peripheral blood leukocytes [ SMD=1.32; 95% CI (0.76, 1.89) ; P<0.000 01], platelets [ MD=25.05; 95% CI (8.00, 42.10) ; P=0.004], hemoglobin [ MD=24.14; 95% CI (16.34, 31.94) ; P<0.000 01] and clinical symptoms [ RR=1.38; 95% CI (1.25, 1.52) ; P<0.000 01] between the chemotherapy group, the chemotherapy combined with the western medicine group and the traditional Chinese medicine compound group. Conclusions:The traditional Chinese medicine compound based on astragalus and angelica can improve the level of peripheral blood cells, reduce bone marrow suppression, and improve clinical symptoms and quality of life of patients with cancer after chemotherapy. However, due to the low quality of the included literature and the large heterogeneity of some of the results, more rigorously designed high-quality RCTs are needed for further verification.

Objective To explore the effect of static progressive stretching combined with joint mobilization on dysfunction after total knee arthroplasty.Methods Fifty-six patients with knee joint dysfunction after total knee arthroplasty were randomly divided into a treatment group and a control group,each of 28.Both groups were treated with joint mobilization,while the treatment group was additionally provided with static progressive stretching for 8 weeks.Before and after the treatment,both groups' pain and knee function were evaluated using visual analogue scale (VAS) scores,the range of motion and the hospital for special surgery knee score (HSS).Results Before the treatment there were no significant differences between the two groups in any of the measurements.After the treatment,all of the measurements had improved in both groups,on average.Compared with the control group,the treatment group's average range of motion of the knee and HSS score were significantly better.Conclusion Static progressive stretches combined with joint mobilization can effectively relieve pain,expand the range of motion and improve the function of a knee joint after total knee arthroplasty.