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Investigation on thermal characteristics and desensitization mechanism of improved step ladder-structured nitrocellulose

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Defence Technology（防务技术） 2023年第2期20卷 93-102页

作者： Cheng-kai pu Yu Luan Ming-jun Yi zheng-gang Xiao Key Laboratory of Special Energy Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing210094People's Republic of China

Nitrocellulose,or cellulose nitrate,has received considerable interest due to its various applications,such as propellants,coating agents and gas ***,its high mechanical sensitivity caused many accidents during its storage and usage in *** this work,two kinds of insensitive step ladderstructured nitrocellulose(LNC)with different nitrogen contents were *** products were characterized by FT-IR,Raman,XRD,SEM,elemental analysis,TGA,DSC,accelerating rate calorimeter analysis(ARC),and drop weight test to study their molecular structure,thermal characteristics and desensitization *** with raw nitrocellulose,LNC has a sharper exothermic peak in the DSC and ARC *** H50values of the two kinds of LNC increased from 25.76 to 30.01 cm for low nitrogen content and from 18.02 to 21.84 cm for high nitrogen content,*** results show that the ladder-structure of LNC which provides regular molecular arrangement and a soft buffer made with polyethylene glycol could affect the energy releasing process of LNC and reduce the sensitivity of *** LNC provides an alternative to be used as a binder in insensitive propellants formulation.

关键词： Nitrocellulose Decomposition Desensitization Ladder structure Thermal characteristic Polyethylene glycol

The relationship between insulin resistance/β-cell dysfunction and diabetic retinopathy in Chinese patients with type 2 diabetes mellitus： the Desheng Diabetic Eye Study

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International Journal of Ophthalmology(English edition) 2018年第3期11卷 493-500页

作者： Yun-Yun Li Xiu-fen Yang Hong Gu Torkel Snellingen Xi-pu Liu Ning-pu Liu Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology and Visual Sciences Key Laboratory Beijing 100730 China Department of Ophthalmology Friendship Hospital Capital Medical University Beijing 100050 China Department of Ophthalmology Lihuili Hospital Ningbo 315040 Zhejiang Province China Sekwa Institute of Medicine Beijing 100035 China

AIM： To investigate the relationship between insulin resistance （IR）/β-cell dysfunction and diabetic retinopathy （DR） in Chinese patients with type 2 diabetes mellitus （T2DM）, and to explore further whether there were differences in the relationship among diabetic patients with higher and lower body mass index （BMI）. METHODS： Cross-sectional study. A total of 1466 subjects with T2DM were recruited in a local Desheng Community of urban Beijing from November 2009 to June 2012 for the cohort of Beijing Desheng Diabetic Eye Study. Standardized evaluation was carried out for each participant, including questionnaire, ocular and anthropometric examinations, and laboratory tests. Seven fields 30° color fundus photographs were used for DR grading according to the Early Treatment Diabetic Retinopathy Study protocols. Homeostatis Model Assessment （HOMA） method was employed for IR and β-cell function assessment. RESULTS： After excluding those participants who were treated with insulin （n=352） or had missing data of fasting insulin （n=96）, and further excluding those with poor quality of retinal photographs （n=10）, a total of 1008 subjects were included for the final analysis, 406 （40.3%） were men and 602 （59.7%） were women, age ranging fiom 34 to 86 （64.87±8.28）y. Any DR （levels 14 and above） was present in 278 （27.6%） subjects. After adjusting for possible covariates, the presence of any DR did not correlate with HOMA IR [odds ratio （OR） 1.51, 95% confidence interval （Cl） 0.87-2.61, P=0.14] or HOMA β-cell （OR 0.71, 95%CI 0.40-1.26, P=0.25）. After stratification by BMI, the presence of any DR was associated positively with HOMA IR （OR 2.46, 95%CI： 1.18-5.12, P=0.016）, and negatively with HOMA β-cell （OR 0.40, 95%CI： 0.19-0.87, P=0.021） in the group of patients with higher BMI （225 kg/m2）. In the group of patients with lower BMI （〈25 kg/m2）, the presence of any DR was not associated with HOMA IR （OR 1.00, 95%C1： 0.43-2.33, P=I.00） or HOMA β-cell （OR 1.41, 95%CI： 0.60-3.32, P=

关键词： type 2 diabetes mellitus diabetic retinopathy insulin resistance β-cell function body mass index

The Beijing Desheng Diabetic Eye Study:rationale,design,methodology and baseline data

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International Journal of Ophthalmology(English edition) 2018年第1期11卷 108-116页

作者： Yun-Yun Li Xiu-fen Yang Hong Gu Xi-pu Liu Torkel Snellingen Ning-pu Liu Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Ophthalmology and VisualSciences Key LaboratoryBeijing 100730China Department of Ophthalmology Friendship HospitalCapitalMedical UniversityBeijing 100050China Department of Ophthalmology Ningbo Medical TreatmentCenter Lihuili HospitalNingbo 315040Zhejiang ProvinceChina Sekwa Institute of Medicine Beijing 100035China

AIM： To present the rationale, design, methodology, and the baseline data of the Beijing Desheng Diabetic Eye Study（BDDES）, and to determine the prevalence of diabetic retinopathy（DR） and possible risk factors in patients with type 2 diabetes mellitus（T2DM） in an urban community of Beijing, ***： Community-based prospective cohort study of persons diagnosed with T2DM aged 30 y or older. The main variables of interest are the presence and progression of DR as determined by the standardized ETDRS grading of seven fields fundus photographs. The presence and severity of DR were analyzed for possible correlations to non-genetic and genetic ***： A total of 1438 participants with data available for analysis, the prevalence of any DR was 35.4%. The prevalence of mild non-proliferative diabetic retinopathy（NPDR）, moderate NPDR, severe NPDR, and proliferative diabetic retinopathy was 27.7%, 2.6%, 0.5% and 4.5%, respectively. By multiple logistic regression analysis, risk factors for the presence of any DR included male（P=0.031）, lower income level（P=0.011）, lower education background（P=0.022）, longer duration of diabetes（P=0.001）, younger age at diabetic onset（P=0.001）, higher systolic blood pressure（P=0.007）, higher glycosylated hemoglobin A1 c levels（P=0.001）, high albuminuria（P=0.03）, and use of insulin（P〈0.001）. For vision-threatening DR, four factors were significant： younger age at diabetic onset（P〈0.001）,higher systolic blood pressure（P=0.042）, high albuminuria（P〈0.001）, and use of insulin（P〈0.001）. CONCLUSION： The BDDES is the first large-scale ongoing cohort study of a Chinese urban population of persons with type 2 diabetes. Using standardized grading system comparable to large cohort studies from western populations, our baseline data shows that the prevalence of DR and major risk factors in this Chinese ethnic population are comparable to that found in the western population studies.

关键词： type 2 diabetes mellitus diabetic retinopathy risk factors cohort study

Magnetic field and performance analysis of a tubular permanent magnet linear synchronous motor applied in elevator door system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 572-576页

作者： Xiao LIU Yun-yue YE Zhuo zheng Qin-fen LU School of Electrical Engineering Zhejiang University Hangzhou 310027 China

A novel elevator door driven by tubular permanent magnet linear synchronous motor (TPMLSM) is presented. This TPMLSM applies axial magnet array topology of the secondary rod, air-cored armature windings and slotless structure of the forcer to improve the stability of the thrust. The influence of two major dimensions, the pitch and radius of the permanent magnet (PM), on magnetic field was studied and the best values were given by the finite element analysis (FEA). The magnetic field, back EMF and thrust of the motor were analyzed and the PM size was optimized to reduce the harmonic components of the magnetic field and improve the performance of the motor. Predicted results are validated by the experiment. It is shown that the performance of the motor and the novel elevator door system is satisfying.

关键词： Elevator door system Tubular permanent magnet linear synchronous motor (TPMLSM) Finite element analysis(FEA)

端粒长度与10种常见肌肉骨骼疾病的关系孟德尔随机化分析

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中国组织工程研究 2025年第3期29卷 654-660页

作者：罗伟东蒲彬古鹏黄枫郑晓辉陈福洪广州中医药大学第一附属医院广东省广州市510000 广州中医药大学第一临床医学院广东省广州市510000 川北医学院附属遂宁市中医医院骨一科四川省遂宁市629000

背景:多项观察性研究表明,端粒长度与肌肉骨骼疾病之间存在潜在的关联,然而它们之间的潜在机制仍不清楚。目的:利用两样本孟德尔随机化分析来探索端粒长度与肌肉骨骼疾病之间的遗传因果关系。方法:从英国生物银行中获得端粒长度的全基... 详细信息

背景:多项观察性研究表明,端粒长度与肌肉骨骼疾病之间存在潜在的关联,然而它们之间的潜在机制仍不清楚。目的:利用两样本孟德尔随机化分析来探索端粒长度与肌肉骨骼疾病之间的遗传因果关系。方法:从英国生物银行中获得端粒长度的全基因组关联研究汇总数据。从FinnGen财团中获得了关于10种常见肌肉骨骼疾病(骨坏死、骨髓炎、骨质疏松、类风湿关节炎、腰痛、椎管狭窄、痛风、肩周炎、强直性脊柱炎和下肢深静脉血栓)的全基因组关联研究汇总数据。使用逆方差加权、孟德尔随机化-Egger和加权中位数方法评估端粒长度与10种肌肉骨骼疾病的因果关系,逆方差加权作为主要的孟德尔随机化分析方法,并进行敏感性分析探讨结果稳健性。结果与结论:①逆方差加权法结果表明,遗传预测的端粒长度与类风湿关节炎(OR=0.78,95%CI:0.64-0.95,P=0.015)和骨坏死(OR=0.56,95%CI:0.36-0.90,P=0.016)风险之间存在负向因果关系,但未发现端粒长度与其他8种肌肉骨骼疾病之间存在因果关系(P均>0.05)。②敏感性分析结果表明因果关系稳健,孟德尔随机化-Egger截距分析未检测到潜在的水平多效性(P均>0.05)。③此项孟德尔随机化研究支持端粒长度对类风湿关节炎和骨坏死的保护作用的结论,然而,未来将需要更多的基础和临床研究来验证。

关键词：端粒长度肌肉骨骼疾病孟德尔随机化全基因组关联研究单核苷酸多态性因果关系工具变量

Investigation of combined degrader for proton facility based on BDSIM/FLUKA Monte Carlo methods

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Nuclear Science and Techniques 2022年第2期33卷 30-39页

作者： Man-fen Han Jin-Xing zheng Xian-Hu Zeng Jun-Song Shen Hefei Institutes of Physical Science Chinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

The significant advantage of proton therapy over other particle-based techniques is in the unique physical characteristics of the Bragg *** can achieve a highly conformal dose distribution and maximize the probability of tumor control by varying the irradiation *** proton facilities use cyclotrons for fixed energy beam extraction and are equipped with degrader and collimator systems for energy modulation and emittance ***,interactions between charged particles and degrader materials inevitably cause beam loss and divergence and deteriorate beam performance,which present great challenges for downstream transport and clinical *** this work,we investigate a method of energy reduction by combining boron carbide and graphite in a degrader to obtain greater beam transmission at lower *** results demonstrate that the beam size and emittance at the exit of the combined degrader diverge less than those of multi-wedge one in the energy range of 70-160 ***,the transmission efficiency after the first dipole also shows improvements of 36.26%at 70 MeV and 70.55%at 110 *** a component with a high activity level,the degrader causes additional ambient radiation during *** induced radiation even remains several hours after system *** of material activation and induced radiation based on 1 h irradiation with a 400 nA beam current shows that the combined degrader has a definite advantage in shielding despite producing more secondary *** radioactivity and average ambient dose equivalent are reduced by 50%compared with the multiwedge degrader at the important cooling time of 1 *** 12 h and 24 h of cooling,the radiation levels of degraders decrease slightly due to the presence of long half-life residual *** average dose generated from the multi-wedge degrader is still 1.25 times higher than that of the combined one.

关键词： Proton therapy Degrader Boron carbide Transmission efficiency Radionuclide Ambient dose equivalent

Association of candidate gene polymorphisms with diabetic retinopathy in Chinese patients with type 2 diabetes

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International Journal of Ophthalmology(English edition) 2020年第2期13卷 301-308页

作者： Wen-Ying Fan Hong Gu Xiu-fen Yang Chong-Yang She Xi-pu Liu Ning-pu Liu Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Ophthalmology and Visual Sciences Key LaboratoryBeijing 100730China Department of Ophthalmology Lihuili HospitalNingbo 315010Zhejiang ProvinceChina Department of Ophthalmology Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Ophthalmology Beijing Chao-Yang HospitalCapital Medical UniversityBeijing 100020China Sekwa Eye Hospital Sekwa Institute of MedicineBeijing 100035China

●AIM:To investigate the association between a set of six candidate genes and the risk of diabetic retinopathy(DR)in an urban community cohort of Chinese patients with type 2 diabetes mellitus(T2 DM).●METHODS:A population-based cross-sectional *** diabetic subjects were recruited from an urban community in Beijing and categorized into groups of proliferative diabetic retinopathy(PDR),non-proliferative diabetic retinopathy(NPDR),or diabetic without any retinopathy(DWR)based on the fundus photography and duration of *** candidate genes,including advanced glycation end product specific receptor(AGER),aldose reductase(AKR1 B1),inducible nitric oxide synthase(i NOS),pigment epithelium derived factor(PEDF),tumor necrosis factor-alpha(TNF-α),and paraoxonase 1(PON1),were chosen based on Meta-analysis of genetic association studies for DR and biochemical pathways implicated in DR *** allele and genotype distribution of 21 functional singlenucleotide polymorphisms(SNPs)in those 6 candidate genes were investigated using MassARRAY genotyping system.●RESULTS:Among 1461 diabetic patients recruited from community,569 were selected in following genotyping analysis,including 97 patients with PDR,217 with NPDR,and 255 with *** the promoter variant rs1051993 in AGER gene,the distribution of allele and genotype in PDR group differed from that in DWR group(allele:P=0.011;genotype:P=0.01).Compared with DWR,patients with PDR had lower frequencies of heterozygous genotype GT(9.8%for DWR,1%for PDR,OR:0.10,95%CI:0.01-0.72)and minor allele T(4.9%for DWR,0.5%for PDR,OR:0.10,95%CI:0.01-0.75).In multivariate model,the distribution of genotype for rs1051993 in PDR group was significantly different from that in DWR group(GT vs GG:OR:0.07,95%CI:0.01-0.61,P<0.001).No association with DR was observed in other genotyped SNPs.●CONCLUSION:The data suggest a significant association of the promoter variant rs1051993 in AGER gene with PDR in Chinese cohort with T2DM.

关键词： polymorphisms diabetic retinopathy AGER AKR1B1 iNOS PEDF TNF-α PON1

Adult rhabdomyosarcoma combined with acute myeloid leukemia: A case report

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World Journal of Clinical Cases 2024年第3期12卷 582-586页

作者： Lu zheng fen-Juan Zhang Department of Hematology Lishui Municipal Central HospitalLishui 323000Zhejiang ProvinceChina

BACKGROUND Rhabdomyosarcoma is a tumor of mesenchymal *** leukemia is a complication of previous transformation to other hematologic disorders or is a treatment-related acute myeloid leukemia secondary to cytotoxic chemotherapy or radiation therapy for other *** SUMMARY We present the case of a 36-year-old female patient who was diagnosed with rhabdomyosarcoma and acute myeloid *** disease progression was observed after multiline ***,the patient suffered cerebral hemorrhage,which resulted in *** The incidence of rhabdomyosarcoma in adults is extremely low,and secondary leukemia caused by rhabdomyosarcoma is even *** leukemia has a very poor prognosis and a low overall survival rate.

关键词： Rhabdomyosarcoma Secondary acute myeloid leukocytes Chemotherapeutics Secondary leukemia Case report

Determining H0 using a model-independent method

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Frontiers of physics 2017年第1期12卷 133-140页

作者： pu-Xun Wu zheng-Xiang Li Hong-Wei Yu Center for Nonlinear Science and Department of Physics Ningbo University Ningbo 315211 China Center for High Energy Physics Peking University Beijing 100080 China Department of Astronomy Beijing Normal University Beijing 100875 China

By using type Ia supernovae （SNIa） to provide the luminosity distance （LD） directly, which depends on the value of the Hubble constant H0 = 100h km·s^-1· Mpc^-1, and the angular diameter distance from galaxy clusters or baryon acoustic oscillations （BAOs） to give the derived LD according to the distance duality relation, we propose a model-independent method to determine h from the fact that different observations should give the same LD at a given redshift. Combining the Sloan Digital Sky Survey II （SDSS-II） SNIa from the MLCS2k2 light curve fit and galaxy cluster data, we find that at the 1σ confidence level （CL）, h = 0.5867±0.0303 for the sample of the elliptical β model for galaxy clusters, and h = 0.6199± 0.0293 for that of the spherical β model. The former is smaller than the values from other observations, whereas the latter is consistent with the Planck result at the 2σ CL and agrees very well with the value reconstructed directly from the H（z） data. With the SDSS-II SNIa and BAO measurements, a tighter constraint, h = 0.6683 ± 0.0221, is obtained. For comparison, we also consider the Union 2.1 SNIa from the SALT2 light curve fitting. The results from the Union 2.1 SNIa are slightly larger than those from the SDSS-II SNIa, and the Union 2.1 SNIa ＋ BAOs give the tightest value. We find that the values from SNIa ＋ BAOs are quite consistent with those from the Planck and the BAOs, as well as the local measurement from Cepheids and very-low-redshift SNIa.

关键词： Hubble constant luminosity distance angular diameter distance