Investigation on the factors influencing the thickness distribution of superplastic-formed components

In the superplastic sheet forming process, the uniformity of the sheet's final thickness distribution is vital for ensuring the good mechanical quality of the formed components. The influences of the component shape and the contact friction on the final thickness distribution were investigated in this work by using finite element method on a series of axisymmetric models. It was concluded that shape optimization and friction elimination are required to get uniform thickness distribution, and eventually to improve the mechanical quality of the formed components. The constitutive equation of the Ti-6A1-4V superplastic material was also determined on the basis of experimental data.

Determination of ice thickness,subice topography and ice vol-ume at Glacier No.1 in Tien Shan,China by ground penetrating radar

We describe a radio-echo sounding (RES) survey for the determination of ice thickness, subglacial topography and ice volume of Glacier No. 1 , in Tien Shan, China, using ground-penetrating radar (GPR). Radar data were collected with 100-MHz antennas that were spaced at 4 m with a step size of 8 m. The images produced from radar survey clearly show the continuity of bedrock echoes and the undulation features of the bedrock surface. Radar results show that the maximum ice thickness of Glacier No. 1 is 133 m, the thickness of the east branch of Glacier No. 1 averages at 58. 77 m while that of the west branch of Glacier No. 1 averages at 44. 84 m. Calculation on ice volume indicates that the ice volume of the east branch of Glacier No. 1 is 51. 87 × 106 m3 and that of the west branch of Glacier No. 1 is 20. 21 × 106 m3. The amplitude of the undulation of the bedrock surface topography revealed by radar profiles is larger than that of the glacier surface topography, indicating that the surface relief does not directly depend on that of the bedrock undulation in Glacier No. 1 , in Tien Shan.

Verifying the Effects of an Education Program Leveraging Information Technology to Promote Cervical Cancer Screening in Women Aged 20 - 29—A One-Year Longitudinal Study

The purpose of this research is to implement an IT-based education program in order to promote cervical cancer screenings for women aged 20 - 29 years, as well as to examine the results of said program. This is a longitudinal/comparative study of two groups, one for which the program was implemented (the intervention group), and the other for which it was not (the control group). The program consisted of attending a health lecture and encouragement to be screened one month, six months, and one year later sent through IT-based methods. The target was unmarried women aged 20 - 29 who had neither previously given birth nor had been screened for cervical cancer in a period one year prior. They were divided into two groups, the intervention group (n = 142) and control group (n = 145). The effectiveness of the program was assessed via an initial survey and further surveys six months and one year later. Results were based on the Japanese version of the Health Belief Model Scale for Cervical Cancer and the Pap Smear Test (HBMSCCPST), knowledge scores in the categories of Healthy Lifestyles, Cervical Cancer, Cervical Cancer Screening, and screening behavior. A two-way ANOVA of the HBMSCCPST subscales and knowledge scores in the initial, six-month, and one-year surveys was performed, showing interaction in Cervical Cancer (p = 0.00). Main effects were observed in Cervical Cancer Screening (p = 0.00) and Healthy Lifestyles (p = 0.00). Regarding the amount of change from the initial survey, knowledge scores in the Cervical Cancer (p = 0.027) and Cervical Cancer Screening (p = 0.016) categories were significantly higher in the intervention group than in the control group. There was no significant difference in cervical cancer screening rates (p = 0.26) between the two groups. However, a small-degree effect size was observed for Benefits, Seriousness, and Susceptibility subscales in both examinees and non-examinees. Although the educational program of this study was effective in improving the knowledge of women in their twenties, there was little improvement in HBMSCCPST and it did not lead to the promotion of cervical cancer screening. In order to raise interest in cervical cancer screening, it is necessary to consider useful content to guide women to consult with healthcare professionals, a long-term population approach, and organizational structure of consultation.

A novel four-legged loaded element thick-screen frequency selective surface with a stable performance

A thick-screen frequency selective surface （FSS） has not only a broad bandwidth but also the advantages of overcoming the multilayer FSS shortcoming of complex structure and low transmittance of centre frequency due to the cascade of FSSs, and this means it could potentially be applied in a stealth curved streamlined radome. However, there is an unsteadiness of centre frequency in a wide range of incident angles and another unsteadiness of polarization in a big incident angle. In order to solve these problems, in this paper we provide a novel four-legged loaded element thick-screen FSS. The structure is analysed and simulated using the mode matching method and moment method. The centre frequency, the transmittance of centre frequency, and bandwidth of the structure are investigated when some parameters including the polarization at a big incident angle and the incident angles of TE ＆： TM waves are changed. The novel four-legged loaded element thick-screen FSS has better transmission properties with a better steadiness of polarization and incident angle independence. The novel structure of the four-legged loaded element thick-screen FSS provides a valuable reference for their application in a stealth curved streamlined radome.

Primer Screening on Germplasm Resources of Mallotus oblongiolus by ISSR Molecular Marker

[ Objective] To provide effective primers for the rapid and accurate ISSR analysis of the germplasm materials of Mallotus oblongiolus （Miq.） Muello-Arg.. [Method] The modified CTAB method was used in the extraction of the genomic DNA. 99 ISSR primers were used in the ISSR-PCR amplification for 20 germplasm materials from 10 populations in Hainan Island, so that some primers, which were suitable to all gerplasm materials of M. oblongiolu, could be selected. [ Result] 15 effective primers with characteristics of rich polymorphism, clear bands, and good repeatability were selected from 99 test primers. The 15 primers selected were used in the ISSR-PCR amplification for 66 germplasm materials of M. oblongiolus. From all of which the abundant and distinct DNA fingerprintings could be obtained. 286 DNA bands were obtained, and of which 231 bands were polymorphic, which amounted to 80.77% of the total bands amplified. And 19.1 bands could be obtained with each primer, averagely. [ Conclusion] The 15 primers selected could be effectively applied to ISSR analysis of the germplasm resources of M. oblongiolus.

Dynamics and screening characteristics of a vibrating screen with variable elliptical trace

The ideal motion characteristics for the vibrating screen was presented according to the principle of screening process with constant bed thickness.A new vibrating screen with variable elliptical trace was proposed.An accurate mechanical model was constructed according to the required structural motion features.Applying multi-degree-of-freedom vibration theory,characteristics of the vibrating screen was analyzed.Kinematics parameters of the vibrating screen which motion traces were linear,circular or elliptical were obtained.The stable solutions of the dynamic equations gave the motions of the vibrating screen by means of computer simulations.Technological parameters,including amplitude,movement velocity and throwing index,of five specific points along the screen surface were gained by theoretical calculation.The results show that the traces of the new designed vibrating screen follow the ideal screening motion.The screening efficiency and processing capacity may thus be effectively improved.

NT与血清β-hCG、PAPP-A、ADAM12单独及联合检测对孕早期DS的诊断价值

目的:探讨颈部透明层厚度(NT)与血清人绒毛膜促性腺激素(β-hCG)、妊娠相关蛋白A(PAPP-A)及解整合素金属蛋白酶12(ADAM12)单独及联合检测对孕早期唐氏综合征(DS)的诊断价值。方法:选取2019年1月—2023年1月在厦门大学附属第一医院杏林分院经羊膜穿刺确诊的47例DS孕妇作为DS组,另选取同期49例产前检查正常的孕产妇作为对照组,检测并比较两组NT及血清β-hCG、PAPP-A、ADAM12水平,并采用受试者工作特征(ROC)曲线分析NT与血清β-hCG、PAPP-A、ADAM12单独及联合检测对DS的诊断价值。结果:DS组NT及血清β-hCG水平高于对照组,PAPP-A、ADAM12水平均低于对照组,差异有统计学意义(P<0.05)。ROC曲线分析显示,NT与血清β-hCG、PAPP-A、ADAM12联合检测诊断DS的曲线下面积为0.993,预测敏感度、特异度分别为95.7%、98.0%,均高于上述指标单独检测。结论:NT与血清β-hCG、PAPP-A、ADAM12检测对孕早期DS均具有一定的诊断价值,且联合应用诊断效果更高,可作为孕早期DS筛查的有效指标。

Crustal thickness and v_P/v_S ratio in Shanxi Graben, China

Shanxi Graben is in the middle part of the North China Craton, from south to north. With the teleseismic data recorded by Regional Seismograph Networks and the temporary ZBnet-W Seismic Array around east part of Shanxi Graben, we measured the crustal thickness and Vp/Vs ratio beneath each station using the H-K stack of receiver functions. The observed crustal thickness shows obvious lateral variation, increasing gradually from east to west in the Shanxi Graben. Beneath the Shanxi Graben the crust is relatively thicker than both sides of the south and the north. In addition, the Vp/Vs ratio in the north of study zone is higher than that in the south. The highest Vp/Vs ratio exists in the crust of the Xinding basin and the Datong basin. Our study also suggests that high velocity ratio might result from the strong activities of the magmation and volcanism.

Development of a Zebrafish Model for Rapid Drug Screening against Alzheimer＇s Disease

Alzheimer＇s disease, the leading cause of dementia in the elderly, is a complex neurodegenerative disorder which leads to a progressive decline in cognitive functions. A rapid screening model is highly demanded for identification and evaluation of novel anti-Alzheimer＇s disease drugs from a large numbers of compounds. Until now, numerous studies utilized zebrafish model for drug discovery. Since aluminum can induce a similar biological activity in zebrafish as in Alzheimer patients, in this study, we developed a novel animal model using 3 to 5 day post-fertilization larval zebrafish by optimizing the doses and duration of aluminum chloride exposure. Six anti-Alzheimer＇s disease drugs with a variety of mechanisms were tested to validate the newly developed zebrafish model. Importantly, Rivastigmine, ThT, Flurbiprofen and AM-117 could increase the value of Dyskinesia Recovery Rate by 53.4-64%, 169.4-200%, 54.5-96% and 70.9-121%, respectively. Rivastigmine, Memantine, ThT, Flurbiprofen, Rosiglitazone and AM-117 improved the value of Response Efficiency by 86.6-175.1%, 28.2-66.6%, 127.2-236.5%, 118.3-323.7%, 26.6-140.8% and 70.2-161.4%, respectively. Our results suggest that the zebrafish model developed in this study could be a useful tool for high throughput screening of potential novel anti-Alzheimer＇s disease leading compounds targeting acetylcholinesterase, N-methyl-D-aspartic acid receptor, γ-secretase, peroxisome proliferator-activated receptor-γand amyloid-β.

3D打印-激光烧结制备导体和介质厚膜的显微结构与性能

为拓展3D打印技术在厚膜混合集成电路制备领域的应用,提高厚膜浆料烧结效率,采用3D直写+激光烧结制备三种导体浆料厚膜和一种介质浆料厚膜,并与常规的丝网印刷+高温炉烧结厚膜进行显微结构与性能的对比研究。结果表明,常规丝网印刷+高温炉烧结的导体及介质厚膜具有良好的显微结构与性能。相比而言,3D直写+激光烧结制备的导体厚膜平整连续、厚度均匀,焊接性能良好,但结构不够致密,部分导体厚膜存在膜层附着力不足,方阻偏大的问题;介质厚膜激光烧结后的致密性较导体厚膜更低,绝缘性能不满足要求。3D直写制备导体或介质浆料厚膜具有可行性,但激光烧结工艺参数有待优化,以实现厚膜的烧结致密化,提高厚膜与基板的结合强度。

Structural and Dielectric Properties of Dy-doped(Ba,Sr,Ca) TiO_3 Thick Films

Preparation and electrocatalytic activities of Pt-TiO_2 nanotubes(Ba_ 0.57Sr_ 0.33Ca_ 0.10)TiO_3 powders,prepared by the sol-gel method,were doped MnCO_3 as acceptor and Dy_2O_3 as donor.This powder was mixed with an organic vehicle and BSCT thick films were fabricated by the screen-printing techniques on alumina substrate.The structural and dielectric properties of BSCT thick films were investigated with variation of Dy_2O_3 amount.As a result of the differential thermal analysis(DTA),exothermic peak was observed at around 670℃ due to the formation of the polycrystalline perovskite phase.All the BSCT thick films showed the XRD patterns of a typical polycrystalline perovskite structure.The average grain size of BSCT thick films decreased with increasing amount of Dy_2O_3.The relative dielectric constant and dielectric loss of the BSCT thick film doped Dy_2O_3 0.1mol% were 4637.4 and 1.6% at 1kHz,respectively.

Values of macular ganglion cell-inner plexiform layer and 10-2 visual field measurements in detecting and evaluating glaucoma

AIM:To assess the performance of macular ganglion cell-inner plexiform layer thickness(mGCIPLT)and 10-2 visual field(VF)parameters in detecting early glaucoma and evaluating the severity of advanced glaucoma.METHODS:Totally 127 eyes from 89 participants(36 eyes of 19 healthy participants,45 eyes of 31 early glaucoma patients and 46 eyes of 39 advanced glaucoma patients)were included.The relationships between the optical coherence tomography(OCT)-derived parameters and VF sensitivity were determined.Patients with early glaucoma were divided into eyes with or without central 10°of the VF damages(CVFDs),and the diagnostic performances of OCT-derived parameters were assessed.RESULTS:In early glaucoma,the mGCIPLT was significantly correlated with 10-2 VF pattern standard deviation(PSD;with average mGCIPLT:β=-0.046,95%CI,-0.067 to-0.024,P<0.001).In advanced glaucoma,the mGCIPLT was related to the 24-2 VF mean deviation(MD;with average mGCIPLT:β=0.397,95%CI,0.199 to 0.595,P<0.001),10-2 VF MD(with average mGCIPLT:β=0.762,95%CI,0.485 to 1.038,P<0.001)and 24-2 VF PSD(with average mGCIPLT:β=0.244,95%CI,0.124 to 0.364,P<0.001).Except for the minimum and superotemporal mGCIPLT,the decrease of mGCIPLT in early glaucomatous eyes with CVFDs was more severe than that of early glaucomatous eyes without CVFDs.The area under the curve(AUC)of the average mGCIPLT(AUC=0.949,95%CI,0.868 to 0.982)was greater than that of the average circumpapillary retinal nerve fiber layer thickness(cpRNFLT;AUC=0.827,95%CI,0.674 to 0.918)and rim area(AUC=0.799,95%CI,0.610 to 0.907)in early glaucomatous eyes with CVFDs versus normal eyes.CONCLUSION:The 10-2 VF and mGCIPLT parameters are complementary to 24-2 VF,cpRNFLT and ONH parameters,especially in detecting early glaucoma with CVFDs and evaluating the severity of advanced glaucoma in group level.

超声检测胎儿颈背皮肤透明带厚度在产前筛查21-三体综合征的研究

目的探讨超声测量胎儿颈背皮肤透明带厚度(nuchalskinfold thickness,NT)在染色体异常疾病21-三体综合征筛查的应用价值。方法经腹超声测量孕12～27周孕妇1500例胎儿颈背皮肤透明带厚度,并与染色体核型分析及随访后结果作对照。结果1500例胎儿中,21-三体综合征的发病率为3.3‰,其中NT增厚者有62例,其中4例为21-三体综合征;无NT增厚中,有1例21-三体综合征。敏感性为80%,特异性为96.07%,准确性为96.12%,阳性预测值为6.45%。结论NT检测对于21-三体综合征的早期诊断具有重要的意义,是早中期妊娠阶段产前筛查有效可行的方法。

NT联合血清AFP、β-hGG检测对胎儿先天性心脏病早期筛查价值

目的:探究超声检测孕妇胎儿颈项透明层(NT)厚度联合血清甲胎蛋白(AFP)、人绒毛膜促性腺激素(β-hGG)检测对胎儿先天性心脏病早期筛查价值。方法:选取2015年6月—2018年6月到本院产前检查孕妇2315例,在妊娠11~14周时超声检测胎儿NT厚度,15~21周采集外周静脉血,采用时间分辨荧光法检测血清AFP、β-hGG水平。对不同检测结果进行诊断价值分析。结果:NT、AFP、β-hGG,NT联合AFP,NT联合β-hGG,AFP联合β-hGG及3者联合对胎儿先天性心脏病检出率分别为5.7%、4.8%、6.4%、1.4%、1.4%、1.3%、1.2%,且年龄>35岁孕妇胎儿先天性心脏病检出率(5.8%)高于20~35岁孕妇(0.4%)(P<0.05)。血清β-hGG单独检测特异度、准确度低于NT、AFP单独检测,误诊率高于NT、AFP单独检测(P<0.05)。NT、AFP、β-hGG联合检测特异度(99.7%)、阳性预测值(74.1%)、准确度(99.6%)均高于两两联合或单独检测,误诊率(13.0%)最低(P<0.05)。结论:超声NT厚度检查联合血清AFP、β-hGG水平检测胎儿先天性心脏病提高了检测的特异度、阳性预测值,降低误诊率,对孕期胎儿不良预后诊断有重要意义。

超声联合血清学检测在孕早中期序贯筛查21-三体综合征的意义

目的探讨孕早中期采用超声序贯血清学检测对筛查21三体综合征的意义。方法应用超声检测8 375例孕11~13+6周孕妇胎儿颈项透明层厚度(NT)及鼻骨(NB)情况,应用时间分辨荧光免疫法检测孕14~20+6周孕妇血清甲胎蛋白(AFP)及游离人绒毛膜促性腺激素β亚单位(Freeβ-h CG)水平。对筛查结果为高危的孕妇的绒毛或羊水样本进行核型检测。并对其进行随访,观察妊娠结局。结果孕早期超声检查联合孕中期血清学筛查,其灵敏度(88.46%)、特异度(99.96%)较单独超声或血清学筛查均显著升高(P<0.05),假阳性率(76.77%)与假阴性率(0.04%)均降低(P<0.05)。结论孕早期超声检查联合孕中期血清学筛查可以提高21-三体综合征产前筛查的灵敏度和特异度,降低假阳性率和假阴性率,可以广泛开展。

丝网印刷工艺制备高T_c Ba-Y-Cu氧化物超导厚膜

本文报道以化学共沉淀法制备 Ba-Y-Cu 氧化物粉料,用丝网漏印技术在兰宝石晶体和氧化铝陶瓷衬底号印刷成膜,经多段温度下的热处理,获得超导转变温度>90K、零电阻温度达84K 以上的超导材料膜。膜层厚度一般为20～50μm。扫描电镜观测表明,材料层致密、气孔很少。时效试验表明膜层超导电性相当稳定。该技术为超导材料膜的器件应用提供了一条途径。

PbO和Bi_2O_3-Li_2CO_3助烧剂对Pb(Zr_(0.9)Ti_(0.1))O_3厚膜热释电性能的影响

采用丝网印刷工艺制备了Pb(Zr0.9T0.1)O3(PZT)厚膜,研究了过量PbO和Bi2O3-Li2CO3共同助烧对PZT厚膜低温烧结特性、微观结构、相构成以及介电和热释电性能的影响。结果表明:随着过量PbO及Bi2O3-Li2CO3添加量的增加,PZT厚膜的烧结温度和晶粒尺寸均逐渐降低。当PbO过量6.4%(质量分数)、Bi2O3-Li2CO3添加量为5.4%(质量分数)时,PZT厚膜可在900℃低温下致密成瓷,且其热释电系数和探测率优值均得到大幅提高;所得样品在30℃时的热释电系数为10.6×10–8C.cm–2.K–1,探测率优值为8.2×10–5Pa–1/2。

L-乳酸菌的选育及在酒糟基质中的培养

从市售酸乳、泡菜中筛选得到产L-乳酸细菌,通过NTG诱变选育和摇瓶发酵试验,选出两株利用葡萄糖较好的菌株m-58和m-16,以玉米浓醪酒糟清液为基质对2株乳酸细菌进一步驯化培养,得出m-58菌株,更能较好地发酵玉米酒糟清液,产生乳酸,m-58菌株在48h发酵含糖63g/L的玉米浓醪酒糟清液产生50g/L的L-乳酸,m-58菌株适合用于发酵玉米酒糟产乳酸。(孙悟)

S-rough sets and knowledge separation

The conceptions of the knowledge screen generated by S-rough sets are given: f- screen and - screen , and then puts forward - filter theorem, - filter theorem of knowledge. At last, the applications of knowledge separation are given according to - screen and - screen.

Variable elliptical vibrating screen: Particles kinematics and industrial application

Traditional vibrating screen usually adopts the linear centralized excitation mode,which causes the difficulty in particles loosening and low screening efficiency.The variable elliptical vibrating screen(VEVS)trajectory is regulated to adapt the material mass along the direction of the screen length,improving the particles distribution as well as the screening efficiency.In this work,a theoretical model was developed for analyzing the screen surface motion law during VEVS-based screening process.An equation was obtained to show the relationship between the horizontal amplitude and the vertical amplitude.The materials kinetic characteristics were studied by using high-speed camera during screening process.Compared with equal-amplitude screen(EAS),the material moving velocity was increased by 13.03%on the first half but decreased by 3.52% on the second half,and the total screening time was reduced by 9.42% by using VEVS.In addition,-6 mm screening test was carried out.At the length of VEVS equaled to 1.2 m,the screening efficiency and the total misplaced material content were 92.50% and 2.90%,respectively.However,the screening efficiency was 89.91% and the total misplaced material content was 3.76% during EAS-based screening process.Furthermore,when external moisture is 5.96%,the screening efficiency of VEVS could reach 86.95%.The 2 TKB50113 type VEVS with double-layered screen surface used in Huoshizui Coal Mine was 5.0 m in width and 11.3 m in length.The areas of single layer and double layer were 56.5 and 113 m~2,respectively.In industrial production,the processing capacity was 2500-3000 t/h and the screening efficiency was larger than 90%.