急性炎性疾病患者乳酸林格氏液液体动力学

目的:探索炎性疾病患者的乳酸林格氏液（Ringer's lactate,RL）液体动力学特征以及炎性生物标记物是否可以作为协变量影响RL分布和排泄。方法:本研究为前瞻性队列研究。选择40例美国麻醉医师分级（ASA）I-II级，腹腔镜下择期胆囊切除术（胆囊炎组，n=20）或者腹腔镜下急诊阑尾切除术（阑尾炎组，n=20）。所有患者麻醉诱导前开始输注RL，按15 mL/kg，35 min内输毕。采用酶联免疫（enzyme-linked immunosorbent assay,ELISA）方法测定血浆炎症（TNF-α,IL-10和CRP）或者内皮损伤生物标记物（syndecan-1,SDC-1）；利用血红蛋白（Hb）稀释-时间曲线和尿量，使用Phoenix软件，采用非线性混合效应模型分析计算RL液体动力学参数和协变量的影响。结果:与胆囊炎组相比，阑尾炎组RL从组织间隙到血浆的转运速率常数（k21）显著降低（14×10-3min-1 versus 35×10-3min-1;P=0.012）。阑尾炎组C反应蛋白（CRP）升高［中位数38.1(1.8-143.6) μg/mL versus 1.3(0.1-159.0) μg/mL;P<0.001］；与清醒状态相比，麻醉期间（输液开始后30～45 min），液体从中央室中到外周室的转运速率常数（k12）显著增加（57×10-3min-1 versus 32×10-3min-1；P<0.01）。清除速率常数（k10）降低90%（0.6×10-3min-1 versus 5.3×10-3min-1;P<0.001）。无论在清醒状态还是麻醉状态下低血压均能降低液体清除；炎症或者内膜损伤的生物标记物不能作为显著影响RL液体动力学参数的协变量。结论:阑尾炎或者胆囊炎患者术前输入液体后“炎症反应的生物标记物”不是RL的液体动力学的协变量，但是两组患者中，全身麻醉期间输入液体的清除率下降。     

Microscopic examination of the microstructure and deformation of conventional and auxetic foams

Auxetic materials have a negative Poisson’s ratio, that is, they expand laterally when stretched longitudinally. One way of obtaining a negative Poisson’s ratio is by using a re-entrant cell structure. Auxetic foam was fabricated from a conventional polymeric foam. Assuming similar mechanical properties for the solid material comprising the foams, the principle variable affecting the properties of the foam is the geometry of the cells. This means that the unusual mechanical properties of auxetic foams are attributed to the deformation characteristics of re-entrant microstructures. In this paper, the results of optical- and scanning electron-microscopic studies of the geometrical parameters for the different foams examined are presented. Examples of the microstructural deformation mechanisms observed are also presented. Comparison between the conventional foams and their auxetic conversions are also made. This revised version was published online in November 2006 with corrections to the Cover Date.     

我公司进行热电联产的可行性分析

大压差减温减压是能的严重贬值。根据公司供热现状，分析了热电联产的可行性，利用蒸汽余压发电后，再供生产系统各热用户，这样既节约了能源又缓解了集团公司用电紧张的局面，而且有相当可观的经济效益。     

非一致性采集资料地震振幅属性分析

油气藏开发过程的实质就是一个流体置换的过程,这就为非一致性采集资料地震监测提供了可能。本文基于gassmann方程,详细地分析了流体替代时储层物性参数(地震波速度,密度,泊松比等)的变化规律,建立了相应的孔隙度变化地震地质模型。最终对该模型所提取的振幅类属性进行优选技术处理,找到了适合本工区的两种敏感振幅属性,为准确预测目的储层段剩余油的分布奠定了基础。     

Discrete Adaptive Sliding Mode Control of a State-Space System with a Bounded Disturbance

This paper presents the discrete adaptive sliding mode control of a state-space system in the presence of a bounded disturbance. The delta form of the discrete state-space model is used as it closely resembles that of the continuous model. The control law takes into account of the effect of the disturbance by using its approximate value. The system behavior in the vicinity of the sliding surface is studied. It is shown that the adaptive controller leads to a stable closed-loop system. Also, simulation results are presented to illustrate the features of the proposed adaptive control strategy.     

像素值复合置乱的混沌图像加密方法

大部分混沌图像加密方法在进行图像像素值置乱时采用像素值整体处理方式（如异或运算等）,这在抵抗已知明文攻击时是非常脆弱的。针对这个问题,提出了一种基于离散Hopfield反馈神经网络的高维混沌图像加密方法。在进行图像像素值置乱时,操作对象是每个像素的每个比特位,每个像素单元的置乱是一个复合处理过程。通过实验验证了该方法的有效性。     

三维视频编码技术的发展与挑战

介绍了三维视频编码的核心技术。首先比较了纯视频格式和深度增强格式三维视频编码技术的发展方向及面临的挑战,其中重点分析了深度估计技术和视点合成技术的研究思路;然后概括了国际3DV/FTV标准的制定现状;最后对三维视频编码技术进行了总结和展望。     

不产桔霉素红曲诱变菌株的选育及色素发酵条件的优化

利用60Co辐照对原本具有桔霉素生产能力的红曲菌9908进行诱变,筛选得到1株不产桔霉素的菌株,命名为红曲菌9908A,32℃培养6d,色价高于1300U/g。分别采用YES、MSG液态培养和固态培养方式,对该菌株是否产桔霉素进行了详细的研究。结果发现,在这3种培养方式下,该菌株均不产桔霉素。在实验室基础上对该菌株产色素固态发酵条件进行了优化,优化条件为装料量50g、初始加水量60mL、拌料水初始pH5.0、ZnSO4浓度0.2%,优化后的色价维持在2000U/g左右。红曲米中未测出桔霉素。     

An algorithm for function restoration using eigenvectors†

This paper presents an algorithm for the restoration of the characteristics of a function from a finite number of observed points. The algorithm uses the eigenvectors of the Gramian of the observed vectors and is based on the assumption that the function to be constructed can be represented by a specified form. Convergence of the algorithm is proved for the noiseless case. When noise is present, a bound for the error is obtained. For functions not representable in the assumed form, the algorithm can be used to test the non-representability of the function. A numerical example is given to illustrate the theoretical investigation.     

A note on the potential function algorithm for pattern classification†

A system design engineer often resorts to redundancies while maximizing the probability of success of a system designed to perform a certain job over a period, This will have to be done within the resources available. The problem of maximizing system reliability, subject to some linear constraints such as cost, weight or volume, is considered in this paper- The usual problem is transformed to a suitable form and the least square concept is used to develop a solution technique. This type of approach is found to be very simple and faster than earlier methods although the solution is an approximate one.