1.Development of Protective Mask with Dual Canisters & Big Eyes Window for Liquid Propellant
Zhuozhen HAN ; Jixin CONG ; Zhensheng GUO
Chinese Medical Equipment Journal 1989;0(01):-
Objective To develop MFT-2S protective mask with dual canisters and big-eye-window and to improve the three-grade system of protective equipment,so as to solve the problems on protective mask in environment with gas of high concentration.Methods MFT-2S protective mask was derived from MFT-2,with the advantages of MFT-2.The fixation intensity was effectively guaranteed by installing two sets of joint components and stainless steel clamps in the lower part of mask bilaterally.The sealing component was installed in communication component.Each canister was fixed at one side respectively.The fogproof lenses were reinstalled and the length of canister was increased properly.Results The results showed that,compared with MFT-1 mask,the inspiration resistance of MFT-2S mask decreased by a half,its total weight became about 50% of MFT-1 mask,and the leakage coefficient of MFT-2S mask was 0.005 percent.Its antidim character was improved and MFT-2S mask had better protective performance than MFT-2 by twice.Conclusion According to the transformed protection indices,MFT-2S mask,with the advantages of being light,simplified and standardized,can take the place of MFT-1 mask.
2.Testing Method for protection capability of skin protection material against nitro oxidizer
Jixin CONG ; Guangyou ZHANG ; Ye CAO
Chinese Medical Equipment Journal 1993;0(06):-
The experiment method of "Liquid-vapor" permeation for nitro oxidizer's skin protective materials by the indicator of pH test paper is developed,and the method for cankerous testing and evalution roles are confirmed too.The result of the experiment shows that butyl rubber and halogenated butyl rubber have better protective performances for "liquid-vapor" permeation of nitro oxidizer,while fluorine rubber,polyethylene and polyterafluoroethylene have better cankerous protection capabilities.
3.Method of protection permeation testing on skin protection material for liquid rocket propellant
Jixin CONG ; Guangyou ZHANG ; Ye CAO
Chinese Medical Equipment Journal 1989;0(01):-
Objective To explore the method of permeability for skin protective materials of rocket propellant based on the design and make of sealing container. Methods The propellant mass permeated per minute and per square centimeter was calculated by testing the mass through the sample at the fixed time in the sealing container. Results The method of permeability for skin protective materials against rocket propellant was developed by the mass variation of propellant in the sealing container. The limits of 100?g /(cm2?min) was raised to assess if the material had the protection ability. In the meantime, the reliability of material protection behavior was improved. Conclusion The science of the method developed is confirmed by comparing the permeation performance of protection materials at home and abroad, and the method can be the basis to assess the ability of protection materials.
4.The Breast Cancer Cohort Study in Chinese Women: the methodology of population-based cohort and baseline characteristics
Heling BAO ; Liyuan LIU ; Liwen FANG ; Shu CONG ; Zhentao FU ; Junli TANG ; Shan YANG ; Weiwei SHI ; Min FAN ; Minquan CAO ; Xiaolei GUO ; Jixin SUN ; Cuizhi GENG ; Xuening DUAN ; Zhigang YU ; Linhong WANG
Chinese Journal of Epidemiology 2020;41(12):2040-2045
Objective:Breast cancer has been the first cancer among women with the incidence increasing gradually. In September 2016, the Breast Cancer Cohort Study in Chinese Women (BCCS-CW) was initiated, aiming to establish a standardized and sharable breast cancer-specific cohort by integrating the existing cohort resource and improving the quality of follow-up. The BCCS-CW may provide a research basis and platform for the precision prevention and treatment of breast cancer in etiology identification, prevention, early diagnosis, treatment, and prognosis prediction.Methods:We conducted a population-based perspective cohort by questionnaire interview, anthropometry, biological specimens, breast ultrasound and mammography. The cohort was followed by using regional health surveillance and ad hoc survey.Results:Finally, BCCS-CW included 112 118 women, in which 55 419 women completed the standardized investigation and blood specimens were collected from 54 304 women. The mean age of participants was 51.7 years old, 62.7% were overweight or obese, and 48.9% were menopausal.Conclusion:The BCCS-CW will provide population-based cohort resource and research platform for the precise prevention and treatment of breast cancer in Chinese women.
5.Machine-learning-based models assist the prediction of pulmonary embolism in autoimmune diseases: A retrospective, multicenter study
Ziwei HU ; Yangyang HU ; Shuoqi ZHANG ; Li DONG ; Xiaoqi CHEN ; Huiqin YANG ; Linchong SU ; Xiaoqiang HOU ; Xia HUANG ; Xiaolan SHEN ; Cong YE ; Wei TU ; Yu CHEN ; Yuxue CHEN ; Shaozhe CAI ; Jixin ZHONG ; Lingli DONG
Chinese Medical Journal 2024;137(15):1811-1822
Background::Pulmonary embolism (PE) is a severe and acute cardiovascular syndrome with high mortality among patients with autoimmune inflammatory rheumatic diseases (AIIRDs). Accurate prediction and timely intervention play a pivotal role in enhancing survival rates. However, there is a notable scarcity of practical early prediction and risk assessment systems of PE in patients with AIIRD.Methods::In the training cohort, 60 AIIRD with PE cases and 180 age-, gender-, and disease-matched AIIRD non-PE cases were identified from 7254 AIIRD cases in Tongji Hospital from 2014 to 2022. Univariable logistic regression (LR) and least absolute shrinkage and selection operator (LASSO) were used to select the clinical features for further training with machine learning (ML) methods, including random forest (RF), support vector machines (SVM), neural network (NN), logistic regression (LR), gradient boosted decision tree (GBDT), classification and regression trees (CART), and C5.0 models. The performances of these models were subsequently validated using a multicenter validation cohort.Results::In the training cohort, 24 and 13 clinical features were selected by univariable LR and LASSO strategies, respectively. The five ML models (RF, SVM, NN, LR, and GBDT) showed promising performances, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.962-1.000 in the training cohort and 0.969-0.999 in the validation cohort. CART and C5.0 models achieved AUCs of 0.850 and 0.932, respectively, in the training cohort. Using D-dimer as a pre-screening index, the refined C5.0 model achieved an AUC exceeding 0.948 in the training cohort and an AUC above 0.925 in the validation cohort. These results markedly outperformed the use of D-dimer levels alone.Conclusion::ML-based models are proven to be precise for predicting the onset of PE in patients with AIIRD exhibiting clinical suspicion of PE.Trial Registration::Chictr.org.cn: ChiCTR2200059599.