Investigation of the Clinical Diagnostic Significance of the T-Cell Test for Tuberculosis combined with Erythrocyte Sedimentation Test in Pulmonary Tuberculosis

Objective:To investigate the clinical diagnostic significance of peripheral blood T-cell test(T-spot test)for tuberculosis(TB)infection combined with erythrocyte sedimentation rate(ESR)in pulmonary TB.Methods:41 patients with a clinical diagnosis of TB during hospitalization from January 2020 to April 2023 in our hospital were selected as the experimental group,and 45 patients without TB(bronchopneumonia patients)were selected as the control group.The diagnostic specificity,sensitivity,and accuracy of the T-spot TB test,ESR test,and the combined test of the two were calculated respectively.Results:The sensitivity,specificity,and accuracy of the T-spot TB test combined with ESR for the diagnosis of TB in the experimental group were significantly higher than the individual results of the T-spot TB test and ESR test alone(P<0.05).Conclusion:The T-spot TB test combined with the ESR test for TB diagnosis has greater clinical value than carrying out the tests individually.

NHPP-based software reliability model considering testing effort and multivariate fault detection rate

In recent decades,many software reliability growth models（SRGMs） have been proposed for the engineers and testers in measuring the software reliability precisely.Most of them is established based on the non-homogeneous Poisson process（NHPP）,and it is proved that the prediction accuracy of such models could be improved by adding the describing of characterization of testing effort.However,some research work indicates that the fault detection rate（FDR） is another key factor affects final software quality.Most early NHPPbased models deal with the FDR as constant or piecewise function,which does not fit the different testing stages well.Thus,this paper first incorporates a multivariate function of FDR,which is bathtub-shaped,into the NHPP-based SRGMs considering testing effort in order to further improve performance.A new model framework is proposed,and a stepwise method is used to apply the framework with real data sets to find the optimal model.Experimental studies show that the obtained new model can provide better performance of fitting and prediction compared with other traditional SRGMs.

Deformation behaviour in advanced heat resistant materials during slow strain rate testing at elevated temperature

In this study, slow strain rate tensile testing at elevated temperature is used to evaluate the influence of temperature and strain rate on deformation behaviour in two different austenitic alloys. One austenitic stainless steel （AISI 316L） and one nickel-base alloy （Alloy 617） have been investigated. Scanning electron microscopy related techniques as electron channelling contrast imaging and electron backscattering diffraction have been used to study the damage and fracture micromechanisms. For both alloys the dominante damage micromech- anisms are slip bands and planar slip interacting with grain bounderies or precipitates causing strain concentrations. The dominante fracture micromechanism when using a slow strain rate at elevated temperature, is microcracks at grain bounderies due to grain boundery embrittlement caused by precipitates. The decrease in strain rate seems to have a small influence on dynamic strain ageing at 650℃.

Advanced test methods of material property characterization:high strain-rate testing and experimental simulation of multiaxial stress states

Optimum utilization of the loading capability of engineering materials is an important and active contribution to protect nature's limited resources,and it is the key for economic design methods.In order to make use of the materials' resources,those must be known very well;but conventional test methods will offer only limited informational value.The range of questions raised is as wide as the application of engineering materials,and partially they are very specific.The development of huge computer powers enables numeric modelling to simulate structural behaviour in rather complex loading environments-so the real material behaviour is known under the given loading conditions.Here the art of material testing design starts.To study the material behaviour under very distinct and specific loading conditions makes it necessary to simulate different temperature ranges,loading speeds, environments etc.and mostly there doesn't exist any commonly agreed test standard.In this contribution two popular,non-standard test procedures and test systems will be discussed on the base of their application background,special design features as well as test results and typically gained information:The demand for highspeed tests up to 1000 s^(-1) of strain rate is very specific and originates primarily in the automotive industry and the answers enable CAE analysis of crashworthiness of vehicle structures under crash conditions.The information on the material behaviour under multiaxial loading conditions is a more general one.Multiaxial stress states can be reduced to an equivalent stress,which allows the evaluation of the material's constraint and criticality of stress state.Both discussed examples shall show that the open dialogue between the user and the producer of testing machines allows custom-tailored test solutions.

The Extension Rate of the Medial Collateral Ligament of the Knee Joint during the Valgus Stress Test: Two Case Reports

This study aimed to evaluate the influence of measuring the length of the medial collateral ligament (MCL) to compare the MCL burden when the knee joint is placed under valgus stress in the open and closed and closed kinetic chain. Two examiners conducted the examination. The MCL length was measured using ultrasonography. Two subjects were measured in unload bearing and load-bearing positions, with and without valgus stress test at the knee joint extension and 30° flexion, under eight different measurement conditions. The MCL of the subject was delineated in the longitudinal direction using an ultrasound system. The attachment points of the medial femoral and tibial condyle of the MCL were identified, and the ligament length was measured. The MCL rate before and after the valgus stress test in the loading and unloading positions was calculated. The MCL length increased by an average of 8.9% when the external stress test was performed in the non-weight bearing and knee extension positions and by an average of 17.0% when external stress was applied in the non-weight bearing and knee flexion positions. The MCL length increased by an average of 12.2% when the external stress test was performed in the load-bearing and knee extension positions and an average of 8.9% when the valgus stress test was applied in load-bearing and knee flexion positions. In conclusion, the effect of valgus stress on the MCL differs between load-bearing and non-load-bearing positions. It is considered that the dynamic stabilization mechanism works in the knee joint flexion position in the load position and works simultaneously as the static stabilization mechanism, which limits the knee joint valgus and reduces the extension rate of MCL. Therefore, this study reconsiders the shifting of traditional therapy from open kinetic chain to close kinetic chain.

Ministries Design Exchange Rate Stress Test for Labor-Intensive Industries

China’s Ministry of Commerce(MOFCOM)and the Ministry of Industry and Information Technology(MIIT)have designed a stress-test for China’s labor-intensive industries,

The Changes of Heart Rate Power Spectral Density during Head-up Tilt Test

To study the role of autonomic nervous system in the period of developing syncope induced by head-up tilt test(HUT), we analysed the changes of heart rate power spectral density(HRPSD) in 50 patients with unexplained syncope, including 15 positive patients (Group 1) and 35 negative patients(Group 2), and 15 negative healthy persons(Group 3) in 5 minute periods before and after tilting and 5 minutes before the end of test. HRPSD and their changes in total(T), very low-frequence(VLF), low-frequence(LF), high-frequence(HF) and the ratio of low/high frequence(LF/HF) were similar (P>0.05) 5 minutes before and after tilting among three groups. Five minutes before the end of test, Group 1 had obvious increase of T, VLF, LF and LF/HF while Group 2 and 3 had not such significant changes. There was significant difference(P<0.01) compared Group 1 with Group 2, 3. The results showed that the abnormal regulatory function of autonomic nervous system played an important role in the mechanism of symcope induced by HUT, the positive group had abnormal increase of sympathetic tone and imbalance of sympathetic/parasympathetic neural tone before syncope appeared.

腹膜透析相关性腹膜炎的致病菌及药敏试验分析

目的回顾性分析该院腹膜透析相关性腹膜炎(PDAP)的病原菌谱特点及预后转归情况,为该院腹膜炎的防治提供科学依据。方法回顾性选取2017年1月至2023年2月该院收治的69例PDAP患者的临床资料,分析其发病原因、病原菌谱特点及预后转归情况。结果69例PDAP患者腹膜透析透出液共培养出病原菌43例,阳性率为62.32%,43例病原菌中革兰阳性菌23例(53.49%),革兰阴性菌17例(39.53%),真菌3例(6.98%)。43例病原菌感染原因包括肠道感染18例(41.86%),换液操作不规范11例(25.58%),呼吸道感染8例(18.60%),原因不明6例(13.95%)。革兰阳性菌以表皮葡萄球菌(10例)为主,革兰阴性菌以大肠埃希菌(7例)为主。革兰阳性菌对万古霉素、利奈唑胺、替加环素、替考拉宁、莫西沙星均敏感,对克林霉素(52.17%)、红霉素(56.52%)、阿莫西林/克拉维酸(60.87%)、青霉素G(78.26%)耐药;革兰阴性菌对美罗培南、亚胺培南、黏菌素均敏感,对阿莫西林/克拉维酸(47.06%)、头孢呋辛(47.06%)、头孢唑啉(52.94%)、氨苄西林(82.35%)耐药;真菌对氟康唑、伏立康唑、两性霉素B和卡泊芬净均敏感。69例PDAP患者共治愈53例,退出14例,死亡2例,治愈率为76.81%,真菌性PDAP患者退出率明显高于革兰阳性菌、革兰阴性菌及培养阴性的PDAP患者。结论该院腹膜透析患者发生PDAP的主要原因为换液操作不规范和肠道感染,PDAP相关致病菌以革兰阳性菌为主,真菌性PDAP患者退出率较高。

A FAMILY OF SUMMARY CHISQUARE TESTS FOR COMPARING SURVIVAL RATES RATHER THAN CONDITIONAL PROBABILITIES DYING

Objective This paper propses a family of summary chi square tests for comparing survival rates at all points of time between two groups. Methods They are respectively derived from the Peto et al. expression for the log rank test, the Mantel Haenszel expression for the log rank test, and the generalized Wilcoxon test by means of using the homogenetic effective sample size in place of the number at risk and using the corresponding numerator of the conditional probability surviving in place of the death number. Results After such derivations they become clearer in clinical significance, more powerful, and free from the assumption of proportional hazard. Conclusion These tests can be employed in analyzing the clinical data of cancer. A worked example illustrates the methodology.

无量纲化方法选择及最优无量纲化方法构建

文章针对综合评价过程中无量纲化方法难以选择的问题,首先,基于分布特征不变性和变异特征不变性对无量纲化方法进行初步筛选,结果发现,只有伸缩法能同时保持指标的分布特征和变异特征不变;其次,构建无量纲化有效性的统计检验方法,并检验各种伸缩法的有效性,结果发现,并非所有的伸缩法都能有效消除指标间的量纲差异;然后,建立无量纲化信息损失速率的度量模型,提出无量纲化方法选择的主要步骤,并以无量纲化应在有效消除指标间量纲差异的情况下尽可能减小指标内的信息损失速率为原则,构建一种最优无量纲化模型;最后,通过大量的数值模拟实验来进行无量纲化方法选择,并求解最优无量纲化模型。结果发现,基于以上步骤能更加科学准确地进行无量纲化方法选择;构建的最优无量纲化方法不同于任何一种现有的无量纲化方法,其不仅可以有效消除指标间的量纲差异,而且可以防止对数据的过度处理,造成不必要的信息损失。

An Interconnection between Elevated SCC Levels in Milk around the First Artificial Insemination and Pregnancy Rate in Dairy Cows

The aim of this study was to evaluate the impact of the somatic cell count (SCC) levels measured at 28-test-day intervals or pregnancy rate at the first artificial insemination of Holstein Friesian cows. All necessary information was taken from test day and farm records. Levels of SCC in milk, 30 days before, and 30 days after the first artificial insemination (FAI) date were divided into 4 categories and their interconnection with pregnancy rate (PR) at FAI was evaluated by applying logistic models. A SCC threshold of 150.000 cells/ml of milk was used to differentiate uninfected udders and infected udders of Holstein Friesian cows. A level of SCC > 150.000 cells/ml in milk, and a level of SCC < 150.000 cells/ml before and after FAI respectively were considered udders with new infections. A level of SCC > 150.000 cells/ml in milk before FAI as well as after FAI, was considered chronically infected udders or subclinical intramammary infections (IMI). Data from 792 FAIs from farm and test day records over a 4-year period (2019-2022) were evaluated. The outcome of this study revealed that the risk for low PR at the first AI was increased in cows with infected udders (OR = 1.33, CI 0.99 - 1.78), compared with uninfected udders. Increased levels of SCC after FAI had a negative effect on PR, while before FAI was not affected. To achieve a good PR, mastitis control measures must be fully adopted to a large extent around the first AI.

Autonomic Function in Individuals with Slow Heart Rate Response following an Exercise Stress Test

Objective: To examine the autonomic function using HRV measures in apparently healthy individuals undergoing exercise stress test (EST) and demonstrating slow HRR response. Methods: HRV was measured with 12 lead ECGs during graded EST and analyzed via a post-processing method. Autonomic function was determined by Power Spectral Analysis of the very low frequency (VLF), low frequency (LF), high frequency (HF), and the ratio of LF/HF. We correlated HRV indices with resting, exercise, and recovery data. Results: No differences were found in anthropometric measurements, peak EST HR, and METS between individuals with slow HRR (below 18 b/min) compared with controls (HRR > 18 b/min). Only the VLF component of the HRV indices was statistically different (p = 0.03) at one-minute post-exercise compared with controls. Additionally, a significant correlation between HRR and resting LF and HF indices was found in the individuals with slow HRR but not in the controls. Conclusion: In apparently healthy individuals with slow HRR post-EST, autonomic function did not demonstrate any differences at any phase of the EST, including at one minute of recovery. However, a significant correlation was found between resting LF and HF powers and HRR in individuals with slow vagal reactivation post-exercise. The clinical and prognostic implications of such observation deserve further investigation.

系统级单粒子效应试验方法研究

为评估星载电子系统抗单粒子效应敏感性及验证系统级加固方法有效性,本文开展了系统级单粒子效应试验方法的相关研究。验证了采用地面模拟装置以逐一辐照系统中器件方式评估系统功能中断率的可行性,提出可通过多种方式获取器件的敏感性数据,指出直接将系统中器件对应的功能中断截面进行加和求取系统截面曲线的不合理之处,本研究为开展系统级单粒子效应试验提供了技术支撑。

加速碳化条件下不同养护制度对碱矿渣混凝土钢筋锈蚀的影响

研究了加速碳化环境(CO_(2)浓度为20%)下,标准养护、饱和Ca(OH)_(2)溶液养护和蒸压养护对CaO+Na_(2)CO_(3)为激发剂的碱矿渣混凝土(CNC)中钢筋锈蚀的影响。结果表明,与标准养护相比,饱和Ca(OH)_(2)溶液养护不改变CNC的水化产物,但使其早期水化更加充分,因此平均孔径减小;蒸压养护使CNC水化产物由C-S-H凝胶转化为水榴石与11-?型的托勃莫来石,平均孔径和总孔隙率显著减小。在相同的加速碳化龄期下,与标准养护相比,饱和Ca(OH)_(2)溶液养护和蒸压养护的CNC碳化深度降低、CNC中钢筋发生高概率锈蚀时间延缓、钢筋失重率下降。与相同养护条件下的普通硅酸盐混凝土相比,标准养护和饱和Ca(OH)_(2)溶液养护的CNC中钢筋抗锈蚀能力远小于普通硅酸盐混凝土,而蒸压养护的CNC中钢筋抗锈蚀能力大于普通硅酸盐混凝土。

一类Lindley模型参数的经验Bayes检验收敛速度的改进

利用递归核估计和单调性,构造了Lindley模型参数的经验Bayes检验函数,并在适当的条件下,证明了收敛速度的阶可任意接近O(n^(-1)).

低应变率冲击荷载下节理花岗岩的动力响应规律

岩体中节理面的存在是引起冲击应力波衰减的主要原因,会造成爆炸能量的衰减及降低爆破效果。为探讨低应变率下不同节理倾角花岗岩在冲击荷载作用下的动态力学性质、应力波传递规律和能量传递规律,利用分离式霍普金森压杆(split Hopkinson pressure bar,简称SHPB)试验装置对低应变率下3种不同冲击气压、4种不同倾角的节理花岗岩进行冲击试验。结果表明:(1)在含节理的岩样中,其峰值应力随节理倾角的增大呈下降趋势,随冲击荷载的增大呈上升趋势;(2)透射系数随节理倾角的增加先增大后减小,随冲击荷载的增大先减小后增大;(3)能量传递系数随节理倾角的增加先增高后降低,完整岩样、节理倾角θ=0º和45º的岩样,其能量传递系数都随着冲击荷载的增大而减小,而节理倾角θ=15º和30º的岩样,其能量传递系数随着冲击荷载的增大先减小后增大。

桥式同心配水器结构优化及其在南堡油田的应用

南堡油田注水开发已处于油藏中后期,为满足油藏“注上水、注够水”的开发需求,大斜度井分注需求逐年增加。此前,大斜度井采用同心分层注水工艺技术后,存在调不动和漏失量大等问题。针对同心配水器存在的问题,对水嘴形状和结构进行优化改进,开展模拟测试并应用于矿场试验。该技术已在油田58口井上成功应用,应用井的最大井斜62.08°,施工成功率100%,初次测调成功率100%,测调效率提升2倍。

某高导热绝缘胶在星载端机可靠性应用评价

针对星载端机对高导热绝缘底填胶可靠性应用需求,开展双组分高导热绝缘胶可靠性及环境适应性综合影响评估。通过导热绝缘胶性能测试标准样件,测试验证本征性能指标及工艺性指标,并分析评估其合格性;设计制作典型BGA菊花链网络结构样件,采用导热胶填充工艺技术,验证导热绝缘胶空洞率对BGA器件焊点的影响,评价其工艺适应性;设计制作星载端机载荷,开展星载产品验收级环境与可靠性试验,验证端机载荷具有经受工作应力和环境应力的能力。该高导热绝缘胶满足星载产品散热及抗高载荷的需求,实现可靠性应用。

西南地区东部夏季降水转化率特征及成因分析

利用格点化降水观测数据集(CN05.1)以及ECMWF再分析资料(ERA5),分析1961—2020年夏季西南地区东部(Eastern Southwest China,ESWC)的降水、水汽含量及降水转化率特征,并利用天气学分析方法初步探究地形分布对降水转化率空间分布差异的影响,最后利用中尺度数值模式WRF4.0(Weather Research and Forecasting Model)设计地形敏感性试验验证地形对西南地区东部夏季降水的作用。结果表明:(1)1961—2020年夏季西南地区东部的降水呈现东多西少的分布特征,但水汽含量却在其东南部和西北部存在两个大值区,水汽大值区降水转化率偏低,强降水区与水汽含量大值区分布存在明显差异,通过分析强降水区与水平风场及垂直速度场的形势配合发现地形是导致此差异的重要因素。(2)WRF模式能较好地模拟出西南地区东部夏季降水的空间分布特征,通过地形敏感性试验发现,区域内大娄山、方斗山及大巴山组成的西南-东北向山地地形分布对降水强度有显著影响,地形高度的降低将导致区域东南部降水量显著减少。(3)敏感性试验中将区域地形高度分别降低一半和去除地形后,区域东南部的降水在月时间尺度中将分别减少9.89%和19.90%。地形高度的改变也会引起区域垂直速度、水平风场、水汽输送及水汽辐合量发生改变,当地形高度降低后,上升运动及西南风明显减弱,水汽输送强度降低,水汽辐合量减少,不利于降水形成。

高应变率冲击荷载下节理花岗岩损伤机制研究

针对冲击荷载作用下贯通节理花岗岩动力响应特征和能量演化规律这一研究目标,以含不同倾角节理花岗岩为研究对象,基于不同倾角节理岩体损伤力学理论模型,开展了高应变率下不同节理倾角花岗岩的分离式霍普金森压杆(split Hopkinson pressure bar,简称SHPB)冲击试验,完成了高应变率下花岗岩的损伤特征研究,获取了岩体动态力学性质和能量耗散特征。研究结果表明:(1)基于Druck-Prager准则和Weibull强度分布准则,结合弹性波理论,建立了不同倾角节理岩体的应力-应变理论模型,该模型能够较好地反映花岗岩的抗压强度、弹性模量随节理倾角变化的动态力学特性,具有较强的倾角效应;(2)相同冲击荷载下,随节理倾角的增大,能量反射系数呈线性上升趋势,能量传递系数呈线性下降趋势,岩样的峰值应力逐渐而减小;相同节理倾角下,随冲击荷载增大,能量反射系数先增大后减小,能量传递系数先减小再增大,能量吸收率随节理倾角的增大而减小;(3)当冲击荷载相同时,完整岩样、节理倾角θ=0°和θ=15°岩样的破碎程度较大,而节理倾角θ=30°和θ=45°岩样的破碎程度较小;当节理倾角相同时,随冲击荷载增大,超过岩样最大抗压强度时,岩样由剪切和拉伸破坏逐渐转化成压碎破坏,且破碎程度也随之增大。