PCT、IL-6、CysC联合检测对脓毒症急性肾损伤诊断及预后评估的价值

目的探讨降钙素原(PCT)、白细胞介素6(IL-6)、胱抑素(CysC)联合检测在脓毒症急性肾损伤(AKI)诊断及预后评估中的价值。方法100例脓毒症患者根据AKI发生情况分为AKI组(n=56)和无AKI组(n=44);AKI患者分为存活组(n=32)和死亡组(n=24)。收集患者临床资料,采用酶联免疫吸附试验检测PCT、IL-6、CysC水平;急性生理功能和慢性健康状况评分(APACHEⅡ)评估病情;采用受试者工作特征(ROC)曲线评估PCT、IL-6、CysC对脓毒症合并AKI诊断及死亡的预测价值。结果AKI组男性比例、年龄、高血压合并糖尿病比例、APACHEⅡ评分、血肌酐(Scr)、PCT、IL-6、CysC水平高于非AKI组,合并症比例、发病时间低于非AKI组(P<0.05)。ROC曲线结果显示,PCT、IL-6、CysC联合诊断脓毒症合并AKI的曲线下面积(AUC)为0.859,敏感度为91.07%,特异度为90.91%,联合诊断效能优于单一指标。死亡组APACHEⅡ评分、PCT、IL-6、CysC水平高于存活组(P<0.05)。ROC曲线结果显示,PCT、IL-6、CysC联合预测脓毒症合并AKI患者死亡的AUC为0.847,敏感度为91.67%,特异度为87.50%,联合预测效能优于单一指标。结论联合PCT、CysC、IL-6指标对脓毒症合并AKI诊断以及预后预测的价值更高。

Adaptability analysis and optimization of log suite for uncased wellbores of shale gas reservoirs:A case study of Sichuan Basin,China

Significant progress has been made in the exploration and development of unconventional gas resources in China since the beginning of the 21st century.With a rapid increase in yield,the exploration and development of shale gas have been upgraded to a level of national strategy.Logging is one of the core technologies in gas exploration and development.However,logging technologies face the challenges of complex geological conditions and well casing environment,high temperature,high pressure,and strong heterogeneity.Despite the rich experience accumulated,unified understanding and implementation specifications are yet to be established for shale gas well logging.Given the analysis and comparison of the effectiveness and adaptability of logging technologies at different stages of shale gas exploration and development for the Sichuan Basin,this study optimizes the log suite to meet the demand for highefficiency exploration and development of shale gas.According to the adaptability analysis of shale gas log suite,the mandatory logging items of exploratory wells should include caliper log(CAL),natural gamma ray spectrometry(NGS)log,spontaneous potential(SP)log,directional survey,borehole compensated sonic log,litho-density log(LDL),compensated neutron log(CNL),dual laterologmicrospherically focused log/dual induction-laterolog log/array induction log,temperature log,elemental capture spectroscopy(ECS)log,formation microimager(FMI)log,and array sonic log.The log suite of appraisal wells is almost the same as that for exploratory wells,excluding the ECS log and microresistivity scanning imaging.Meanwhile,for the logging of horizontal/highly-deviated holes,the log suite of vertical wells should be referred to according to specific well conditions.

不同单节理产状岩石力学性质数值模拟与强度预测模型

节理岩石力学性质对于各类岩体工程长期稳定具有重要意义,而岩石的力学性质受节理产状影响极大,甚至起决定作用。为研究节理产状对岩石强度和破坏模式的影响机制,基于节理产状参数准确预测岩石的单轴抗压强度,采用PFC软件建立了不同单节理产状的岩石数值模型,开展了一系列单轴压缩数值模拟试验,得到了节理尺寸和倾角对岩石力学特性的影响规律:随着节理尺寸增大,岩石破坏模式逐渐由沿一定角度的剪切破坏变为节理端部裂纹扩展破坏,单轴抗压强度逐渐减小;随节理倾角增大,当节理倾角小于内摩擦角时,岩石的单轴抗压强度逐渐减小,破坏模式主要是节理端部翼裂纹扩展破坏;当节理倾角超过内摩擦角继续增大时,岩石的单轴抗压强度则逐渐增大,破坏模式主要是沿一定角度穿切岩石或次生裂纹扩展的剪切破坏。在此基础上,结合损伤力学和断裂力学理论提出了单节理岩石单轴抗压强度预测模型,充分考虑了由单节理产状差异导致的不同破坏模式对岩石强度的影响,模型参数易于获取。经算例验证,模型具有较高精度,能够满足工程现场需求。

Steam reforming of acetic acid over Ni/biochar of low metal-loading:Involvement of biochar in tailoring reaction intermediates renders superior catalytic performance

Biochar is a reactive carrier as it may be partially gasified with steam in steam reforming,which could influence the formation of reaction intermediates and modify catalytic behaviors.Herein,the Ni/biochar as well as two comparative catalysts,Ni/Al_(2)O_(3) and Ni/SiO_(2),with low nickel loading(2%(mass))was conducted to probe involvement of the varied carriers in the steam reforming.The results indicated that the Ni/biochar performed excellent catalytic activity than Ni/SiO_(2) and Ni/Al_(2)O_(3),as the biochar carrier facilitated quick conversion of the -OH from dissociation of steam to gasify the oxygen-rich carbonaceous intermediates like C=O and C-O-C,resulting in low coverage while high exposure of nickel species for maintaining the superior catalytic performance.In converse,strong adsorption of aliphatic intermediates over Ni/Al_(2)O_(3) and Ni/SiO_(2) induced serious coking with polymeric coke as the main type(21.5%and 32.1%,respectively),which was significantly higher than that over Ni/biochar(3.9%).The coke over Ni/biochar was mainly aromatic or catalytic type with nanotube morphology and high crystallinity.The high resistivity of Ni/biochar towards coking was due to the balance between formation of coke and gasification of coke and partially biochar with steam,which created developed mesopores in spent Ni/biochar while the coke blocked pores in Ni/Al_(2)O_(3) and Ni/SiO_(2) catalysts.

Thermal pretreatment of willow branches impacts yield and pore development of activated carbon in subsequent activation with ZnCl_(2) via modifying cellulose structure

Development of pore structures of activated carbon(AC)from activation of biomass with ZnCl_(2) relies on content and structure of cellulose/hemicellulose in the feedstock.Thermal pretreatment of biomass could induce dehydration and/or aromatization to change the structure of cellulose/hemicellulose.This might interfere with evolution of structures of AC,which was investigated herein via thermal pretreatment of willow branch(WB)from 200 to 360℃and the subsequent activation with ZnCl_(2) at 550℃.The results showed that thermal pretreatment at 360℃(WB-360)could lead to substantial pyrolysis to form biochar,with a yield of 31.9%,accompanying with nearly complete destruction of cellulose crystals and remarkably enhanced aromatic degree.However,cellulose residual in WB-360 could still be activated to form AC-360 with specific surface area of 1837.9 m~2·g^(-1),which was lower than that in AC from activation of untreated WB(AC-blank,2077.8 m~2·g^(-1)).Nonetheless,the AC-200 from activation of WB-200 had more developed pores(2113.9 m~2·g^(-1))and superior capability for adsorption of phenol,due to increased permeability of ZnCl_(2) to the largely intact cellulose structure in WB-200.The thermal pretreatment did increase diameters of micropores of AC but reduced the overall yield of AC(26.8%for AC-blank versus 18.0%for AC-360),resulting from accelerated cracking but reduced intensity of condensation.In-situ infrared characterization of the activation showed that ZnCl_(2) mainly catalyzed dehydration,dehydrogenation,condensation,and aromatization but not cracking,suppressing the formation of derivatives of cellulose and lignin in bio-oil.The thermal pretreatment formed phenolic-OH and C=O with higher chemical innerness,which changed the reaction network in activation,shifting morphology of fibrous structures in AC-blank to“melting surface”in AC-200 or AC-280.

Distribution of modified Circumpolar Deep Water and its threat in Vincennes Bay,East Antarctica

The Antarctic Bottom Water formation site Vincennes Bay,East Antarctica is experiencing a substantial intrusion of modified Circumpolar Deep Water(mCDW),which may inhibit the formation of Dense Shelf Water(DSW)and drive basal melting of the ice shelves.Based on hydrographic data obtained from March to November in 2012,we evaluated the spatial spread of mCDW over the continental shelf region of Vincennes Bay and the associated temporal evolution of water properties,as well as the sea ice formation effect on water column in the coastal polynya.Results show that two branches of mCDW occupied the deep layers of the continental shelf,distinguished by the potential density(smaller than 27.8 kg/m^(3) or not)when potential temperatureθ=0.5°C in theθ-salinity space.The warmer and less dense branch observed on the east plateau,accessed the eastern ice shelves in the coastal polynya to drive basal melting of ice shelves.In contrast,the other colder and denser branch in the mid-depression reached the western Underwood Ice Shelf.DSW formation was detectable in the coastal polynya during September-November,proving the occurrence of deep convection.Surface heat loss and brine rejection during the intensive sea ice formation contributed to the destratification of the water column in the coastal polynya.It was estimated that at least 1.11±0.79 TW heat carried by mCDW into the inner part of the polynya.

一种基于阵列构型与阵元数量联合优化的分布式雷达主瓣干扰抑制方法

针对单基雷达无法有效抑制伴随式主瓣压制干扰的问题,可通过部署稀疏辅助阵形成等效大孔径阵列,从空域上将主瓣干扰与目标进行分离,但该方法易形成空域栅瓣。针对以上问题,该文提出了一种基于阵列构型与阵元数量双参数迭代优化框架,该框架由阵列构型优化与子阵阵元数量优化两部分组成,其中阵列构型优化固定子阵阵元数量,基于最小方差无失真响应准则在主瓣干扰方向形成零陷,利用改进自适应遗传粒子群算法在孔径尺寸、子阵最小间距和主瓣干扰方向零陷深度等约束条件下优化阵列构型,抑制波束栅瓣;子阵阵元数量优化通过改进自适应遗传粒子群算法在有限子阵阵元数量、主瓣干扰方向零陷深度等约束条件下优化子阵阵元数量,进一步抑制波束栅瓣。此外,通过数值仿真验证了相同参数条件下阵列构型与阵元数量双参数迭代优化框架的有效性。最后,针对典型分布式机动平台协同探测场景,探索了主瓣干扰抑制和栅瓣抑制性能边界。

Ship recognition based on HRRP via multi-scale sparse preserving method

In order to extract the richer feature information of ship targets from sea clutter, and address the high dimensional data problem, a method termed as multi-scale fusion kernel sparse preserving projection(MSFKSPP) based on the maximum margin criterion(MMC) is proposed for recognizing the class of ship targets utilizing the high-resolution range profile(HRRP). Multi-scale fusion is introduced to capture the local and detailed information in small-scale features, and the global and contour information in large-scale features, offering help to extract the edge information from sea clutter and further improving the target recognition accuracy. The proposed method can maximally preserve the multi-scale fusion sparse of data and maximize the class separability in the reduced dimensionality by reproducing kernel Hilbert space. Experimental results on the measured radar data show that the proposed method can effectively extract the features of ship target from sea clutter, further reduce the feature dimensionality, and improve target recognition performance.

Aid of Smart Nursing to Pressure Injury Prevention and Rehabilitation of Textile Cushions

Real-time monitoring of pressure and temperature in wheelchair patients is an effective method for preventing and rehabilitating pressure injuries.Nevertheless,few rehabilitation devices capable of monitoring temperature and pressure have been reported.Herein,we propose a fully textile-based scalable and designable dual-mode rehabilitation cushion for real-time monitoring of pressure and temperature.The different signal output modes(resistive and capacitive signals)enable noninterference between pressure and temperature.The cushion exhibits a wide pressure monitoring range of 2–160 kPa,a high sensitivity of 8.8399 kPa^(−1),and a repeatable stability exceeding 10,000 cycles.In addition,the cushion demonstrates excellent temperature responsiveness with a linearity of 0.995 and a TCR of 0.019 s℃^(−1).Furthermore,an intelligent monitoring system integrated with machine learning has been developed to realize large-range multipoint sensing and data visualization.The system can accurately recognize different sitting postures with an accuracy of 99.65%.Human application evaluations have demonstrated the feasibility of this cushion for preventing pressure injuries,which can stimulate further research on pressure injury prevention and rehabilitation in the future.

冠状动脉心肌桥与颈动脉斑块的相关性研究

目的探讨冠状动脉心肌桥(myocardial bridge,MB)与颈动脉斑块的关系。方法筛选2022年1月—2024年7月因胸痛怀疑冠心病在南京市中医院心内科就诊并行CCTA的368例患者。飞利浦EPIQ 7超声仪测量分析颈动脉斑块;西门子双源ForceCT进行冠脉造影检测心肌桥。结果研究共计纳入261例参与者,平均年龄(64.0±10.4)岁,心肌桥84例(32.2%)。与无心肌桥组患者相比,心肌桥组的冠心病比例较低(25%vs 39%;P=0.03)、左侧颈动脉斑块的比例也较低(40.5%vs 58.2%;P=0.007);颈动脉斑块的长度、厚度以及右侧颈动脉斑块的比例组间无明显差异(P≥0.14)。单变量和多变量逻辑回归分析显示,心肌桥组患者发生左侧颈动脉斑块的风险较低(OR分别为0.49和0.40;P≤0.014)。基于年龄、性别和冠心病等的分层分析显示MB与这些影响因素间对左侧CAS没有交互作用(P int≥0.19)。结论在住院患者中,心肌桥与左侧颈动脉斑块发生风险降低独立相关。

液体火箭发动机翻转对接工装的设计

液体火箭发动机与运载火箭箭体结构对接方式为空中吊装对接,工序多,难度大,耗时长,对接前后工装拆装不便,对接过程中需要吊车吊装保证安全。为解决对接的可靠性、便捷性、安全性问题,应用翻转对接工装,可以提高对接装配质量,缩短对接时间,优化对接工序,减小对接风险,操作更为简单。由此,设计了液体火箭发动机翻转对接工装。介绍了翻转对接工装的设计方案和结构,进行了位移和应力分析。

BArcherFuzzer:An Android System Services Fuzzier via Transaction Dependencies of BpBinder

By the analysis of vulnerabilities of Android native system services,we find that some vulnerabilities are caused by inconsistent data transmission and inconsistent data processing logic between client and server.The existing research cannot find the above two types of vulnerabilities and the test cases of them face the problem of low coverage.In this paper,we propose an extraction method of test cases based on the native system services of the client and design a case construction method that supports multi-parameter mutation based on genetic algorithm and priority strategy.Based on the above method,we implement a detection tool-BArcherFuzzer to detect vulnerabilities of Android native system services.The experiment results show that BArcherFuzzer found four vulnerabilities of hundreds of exception messages,all of them were confirmed by Google and one was assigned a Common Vulnerabilities and Exposures(CVE)number(CVE-2020-0363).

金属铀电子束熔炼实验及数值模拟研究

采用有限元方法对金属铀电子束熔炼过程进行数值模拟,研究了熔炼过程温度场分布。结果表明,单电子束枪熔炼时,熔池中的等温线近似呈半椭圆形,随着电子束功率增加,熔池温度增大,坩埚中被熔化的金属增多。采用双电子束枪熔炼时,可以获得更均匀的温度场,且当电子束功率大于25 kW时,可获得较大的熔池深度和宽度。根据数值模拟结果开展贫化铀电子束熔炼试验,获得的贫化铀铸锭中夹杂物主要集中在铸锭边缘,夹杂物含量明显降低。

基于稀疏采样阵列优化的APG-MUSIC算法

针对稀疏阵列下2维波达方向(DOA)估计问题,该文提出一种基于稀疏采样阵列优化的加速逼近梯度(APG)算法与多重信号分类(MUSIC)算法相结合的2D-DOA估计方法。首先,建立稀疏阵列下的2D-DOA估计信号模型,并证明其具备低秩特征,满足零空间性质(NSP)。其次,为提高稀疏阵列下矩阵填充方法重构接收信号矩阵性能和以此为基础的2D-DOA估计精度,提出基于遗传算法(GA)的稀疏采样阵列优化方法。最后,将APG和MUSIC算法相结合,在重构完整平面阵列接收信号矩阵的基础上完成2维波达方向估计。计算机仿真结果表明,该方法在保证2维波达方向估计精度前提下,大幅提高阵元利用率,有效降低空间谱平均旁瓣,与常规2D-DOA估计方法相比具有优势。

浆细胞性乳腺炎与乳腺导管内癌的超声及MRI影像特点观察

目的 分析浆细胞性乳腺炎与乳腺导管内癌的超声及MRI影像特点。方法 选取2018年12月至2020年12月在本院进行乳腺检查的患者50例作为研究对像,所有患者均接受超声和MRI检查,之后经病理学证实为乳腺导管内癌、浆细胞性乳腺炎患者,观察超声和MRI检查的影像学特点,并探讨联合应用超声和MRI检查的诊断准确率。结果 经病理证实50例患者中浆细胞性乳腺炎20例,乳腺导管内癌30例。与病理结果相比较,超声诊断结果的准确率为58.00%,敏感度55.00%,特异度60.00%;与病理结果相比较,超声联合MRI诊断结果的准确率为90.00%,敏感度85.00%,特异度93.33%。结论 超声和MRI两种检测方法各有优点,对于超声诊断困难的乳腺病患者,可联合MRI进行检测,提高乳腺疾病诊断的准确率,为临床医师治疗方案的制定提供参考依据,现报道如下。

复杂地质条件下巨型水电站岩锚梁开挖施工技术

岩锚梁的开挖施工是水电站地下厂房开挖施工中质量要求最高、工艺要求最严格、技术难度最大的关键部位,岩锚梁开挖的成型质量直接影响到后期岩锚梁的运行安全,是岩锚梁成败与否的第一关键要素。复杂地质条件下岩锚梁开挖难度更大,对技术要求更高。以白鹤滩水电站左岸地下厂房岩锚梁开挖为例,阐述了复杂地质条件下巨型水电站岩锚梁开挖施工技术。

细胞焦亡的研究进展

细胞焦亡(pyroptosis)是促炎形式的程序性细胞死亡,并且依赖于半胱氨酸天冬氨酸特异性蛋白酶(caspases)活性。由caspases通过切割gasermin D(GSDMD)的氨基端和羧基端的连接体调控,后者移位到膜上并穿孔,诱导水分渗透,细胞肿胀并释放炎性因子,继而发生细胞焦亡。细胞焦亡的形态学特征、发生及调控机制等均不同于凋亡、坏死等其他细胞死亡方式,其是机体一种重要的天然免疫反应,在抗击感染以及疾病中均有重要作用。通过对细胞焦亡的更深入研究,可以认知其在相关疾病中的作用,为临床提供新的治疗思路。

风力发电系统的风机齿轮箱故障预测研究

风机齿轮箱是风力发电系统的关键部件,风机齿轮箱故障预测研究是为了减少风机齿轮箱故障,提高齿轮箱运行可靠性。风机SCADA系统参数众多,具有高维度、非线性等特性,因此风机齿轮箱故障预测研究难点技术之一是解决风机高维度、非线性系统等故障预测问题。因此针对上述问题,提出了一种基于皮尔逊相关系数、支持向量回归和统计过程控制相结合的预测方法,首先,利用皮尔逊相关系数对特征变量进行筛选,减少冗余特征变量。然后,利用支持向量回归对风机齿轮箱的正常状态建立预测模型。最后,利用统计过程控制分析预测模型的残差分布,并设定齿轮箱故障预报警阈值。通过仿真,对比了齿轮箱正常与故障状态下的温度预测曲线以及残差分布曲线。仿真结果验证了所提方法对齿轮箱故障预测的有效性。

Cu-Ni合金凝固过程中的宏观偏析模拟

本文采用了有限元方法模拟了Cu-Ni(质量名义成分6.5%)合金铸锭在真空炉冷条件下,铸锭在凝固过程中元素分布与不同部位的凝固时间,模拟结果表明凝固前沿富集的溶质随液流传输到其他区域,导致凝固前沿的浓度有所回升,并在凝固过程中保持相对稳定,铸件完全凝固前,对流作用逐渐减弱,在最后凝固区域形成较大的贫Ni区域。

一种面向边缘环境的多实例服务链在线部署算法

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