Dynamic probability control limits for risk‐adjusted Bernoulli CUSUM charts

The risk‐adjusted Bernoulli cumulative sum (CUSUM) chart developed by Steiner et al. (2000) is an increasingly popular tool for monitoring clinical and surgical performance. In practice, however, the use of a fixed control limit for the chart leads to a quite variable in‐control average run length performance for patient populations with different risk score distributions. To overcome this problem, we determine simulation‐based dynamic probability control limits (DPCLs) patient‐by‐patient for the risk‐adjusted Bernoulli CUSUM charts. By maintaining the probability of a false alarm at a constant level conditional on no false alarm for previous observations, our risk‐adjusted CUSUM charts with DPCLs have consistent in‐control performance at the desired level with approximately geometrically distributed run lengths. Our simulation results demonstrate that our method does not rely on any information or assumptions about the patients' risk distributions. The use of DPCLs for risk‐adjusted Bernoulli CUSUM charts allows each chart to be designed for the corresponding particular sequence of patients for a surgeon or hospital. Copyright © 2015 John Wiley & Sons, Ltd.     

呼吸机常见报警原因分析及处理措施

机械通气作为生命支持和呼吸治疗的有效手段,已广泛应用于临床各个领域,特别是近年来二级甲等医院急诊科建设不断完善、ICU陆续成立,使呼吸机的应用进一步普及。呼吸机报警是机械通气中经常发生的问题,如果处理不当,不仅影响到呼吸机的使用,而且有可能危及到患者的生命,因此正确判断和及时排除报警是极为重要的。对于不是非常熟悉呼吸机应用的临床医护人员对呼吸机报警感到紧张和压力,甚至对报警感到束手无策,不能迅速明确原因,及时正确处理。对呼吸机报警原因进行归纳分析,旨在为临床医护人员处理常见的呼吸机报警提供帮助,进一步提高危重症患者的抢救成功率。     

Demonstration of the reentrant circuit of verapamil-sensitive idiopathic left ventricular tachycardia: direct evidence for macroreentry as the underlying mechanism

The exact reentrant circuit of verapamil-sensitive idiopathic left ventricular tachycardia (ILVT) remains unclear. This case report demonstrates the reentrant circuit of ILVT. A 20-pole electrode catheter was placed along the left posterior fascicle during electrophysiologic study. ILVT was reproducibly induced by programmed ventricular stimulation. During the tachycardia, sequential diastolic potentials bridging the entire diastolic period were observed in the recordings from the electrodes positioned from left ventricular mid-septum to inferoapical septum. The slow conduction zone appeared to be composed of a false tendon in this patient. Entrainment of the ILVT from the right ventricular outflow tract at a different pacing cycle length revealed that a dominant conduction delay occurred at the proximal site of the slow conduction zone. Entrainment studies from several sites on the left ventricular septum confirmed that these sites where sequential electrical activity was recorded were included within the reentrant circuit. However, the left posterior fascicle itself seemed to be a bystander. This report provides the direct evidence of macroreentry as the underlying mechanism of this ILVT, adjacent to the left posterior fascicle.     

Using noise to probe and characterize gene circuits

Stochastic fluctuations (or “noise”) in the single-cell populations of molecular species are shaped by the structure and biokinetic rates of the underlying gene circuit. The structure of the noise is summarized by its autocorrelation function. In this article, we introduce the noise regulatory vector as a generalized framework for making inferences concerning the structure and biokinetic rates of a gene circuit from its noise autocorrelation function. Although most previous studies have focused primarily on the magnitude component of the noise (given by the zero-lag autocorrelation function), our approach also considers the correlation component, which encodes additional information concerning the circuit. Theoretical analyses and simulations of various gene circuits show that the noise regulatory vector is characteristic of the composition of the circuit. Although a particular noise regulatory vector does not map uniquely to a single underlying circuit, it does suggest possible candidate circuits, while excluding others, thereby demonstrating the probative value of noise in gene circuit analysis.     

Temporal changes in N‐acylethanolamine content and metabolism throughout the peri‐adolescent period

Fatty acid amide hydrolase (FAAH) regulates tissue concentrations of N‐acylethanolamines (NAEs), including the endocannabinoid, N‐arachidonylethanolamide (anandamide, AEA). FAAH activity and NAEs are widely distributed throughout the brain and FAAH activity regulates an array of processes including emotion, cognition, inflammation, and feeding. However, there is relatively little research describing how this system develops throughout adolescence, particularly within limbic circuits regulating stress and reward processing. Thus, this study characterized temporal changes in NAE content (AEA, oleoylethanolamine [OEA], and palmitoylethanolamide [PEA]) and FAAH activity across the peri‐adolescent period, in four corticolimbic structures (amygdala, hippocampus, prefrontal cortex, and hypothalamus). Brain tissue of male Sprague–Dawley rats was collected on postnatal days (PND) 25, 35, 45, and 70, representing pre‐adolescence, early‐ to mid‐adolescence, late adolescence, and adulthood, respectively. Tissue was analyzed for AEA, OEA, and PEA content as well as FAAH activity at each time point. AEA, OEA, and PEA exhibited a similar temporal pattern in all four brain regions. NAE concentrations were lowest at PND 25 and highest at PND 35. NAE concentrations decreased between PNDs 35 and 45 and increased between PNDs 45 and 70. FAAH activity mirrored the pattern of NAE content in which it decreased between PNDs 25 and 35, increased between PNDs 35 and 45, and decreased between PNDs 45 and 70. These age‐dependent patterns of NAE content and FAAH activity demonstrate temporal specificity to the development of this system and could contribute to alterations in stress sensitivity, emotionality, and executive function which also fluctuate during this developmental period. Synapse, 2013. © 2012 Wiley Periodicals, Inc.     

橡胶外科手套固定呼吸回路的应用

目的 探讨橡胶外科手套固定呼吸回路的应用效果.方法 选取本院收治的80例需上呼吸机患者作为研究对象,随机分为对照组和观察组,各40例.观察组采用橡胶外科手套配合固定,对照组采用呼吸机本身支架调节,比较两组的应用效果.结果 观察组的并发症发生率为0.O％,显著低于对照组的15.0％,差异有统计学意义（P＜0.05）.观察组的舒适度显著高于对照组,差异有统计学意义（P＜0.05）.结论 采用橡胶外科手套固定呼吸回路,操作简单,成本较低,值得临床推广使用.     

The Effect of Increasing the Amount of Indium Alloying Material on the Efficiency of Sacrificial Aluminium Anodes

Al-Zn-In alloys having 4.2% zinc content and various indium content in the range of 0.02–0.2% were tested with respect to the most important electrochemical properties of sacrificial anodes in a cathodic protection, i.e., the current capacity and potential of the operating anode. The distribution of In and Zn in the tested alloys was mapped by means of the EDX technique, which demonstrated that these elements dissolve well in the alloy matrix and are evenly distributed within it. The current capacity of such alloys was determined by means of the method of determining the mass loss during the dissolution by a current of known charge. The results obtained demonstrate that the current capacity of Al-Zn-In alloy decreases with the increase in the In content, which results in an increased consumption of anode material and shorter lifetime of anodes. With 0.02% In content, the capacity amounted to approx. 2500 Ah/kg, whereas the alloy with 0.2% In had as much as 30% lower capacity amounting to approx. 1750 Ah/kg. Microscopic examination for the morphology and surface profile of the samples after their exposure demonstrated that a higher indium content in the alloy results in a more uneven general corrosion pattern during the dissolution of such alloy, and the cavities (pits) appearing on the alloy surface are larger and deeper. As the indium content is increased from 0.02% to 0.05%, the Al-Zn-In alloy potential decreases by about 50 mV to −1100 mV vs. Ag/AgCl electrode, which is advantageous in terms of using this alloy as a sacrificial anode. When the indium content is further increased from 0.05% to 0.2%, the potential of the alloy is no longer changed to a more negative one. The results obtained from all these tests demonstrate that alloys containing up to 0.05% of In additive are practically applicable for cathodic protection.     

Effect of Copper Sulfate and Sulfuric Acid on Blind Hole Filling of HDI Circuit Boards by Electroplating

Here, in a certain high density interconnect (HDI) printed circuit board, the effect of copper sulfate and sulfuric acid on the filling effect of a blind hole with a certain diameter and depth was investigated by making a blind hole using a CO₂ laser drilling machine, filling the blind hole via electroplating by simulating the electroplating line in a Halin cell, and observing the cross-section of a micro blind hole after polishing using metallographic microscope, as well as the effect of hole filling, are evaluated. The results show that, under the conditions of a certain plating solution formula and electroplating parameters (current density and electroplating time), the sag degree decreases with the increase in the copper sulfate concentration. When the concentration of copper sulfate increases from 210 g/L to 225 g/L, the filling effect is good and the sag degree is about 0. However, with the increase in sulfuric acid concentration, the sag increases gradually. When the sulfuric acid concentration is 25–35 g/L, both the sag and copper coating thickness are in a small range. Under appropriate electroplating conditions, a better blind hole filling effect can be obtained. The volume of blind hole has a certain effect on the diffusion and exchange of copper sulfate and sulfuric acid, as well as on the concentration distribution of additives.     

Role of concealed conduction and allied phenomena in the genesis,maintenance, and termination of cardiac arrhythmias

Concealed conduction is a common electrocardiographic phenomenon whereby a series of events may occur as a result of incomplete propagation of an impulse. The occurrence, maintenance, and resolution (termination) of several events such as functional block and cardiac arrhythmias are linked to concealed conduction. This phenomenon should be suspected on the surface electrocardiogram whenever an arrhythmic event occurs unexpectedly. Several electrophysiological concepts such as transseptal conduction and linking phenomenon are close allies of concealed conduction. His‐bundle electrocardiography and comprehensive electrophysiology may be needed to verify this phenomenon.     

一种医用报警信号测试系统介绍

本文介绍了一种符合《YY0709-2009医用电气设备第1-8部分：安全通用要求并列标准：通用要求,医用电气设备和医用电气系统中报警系统的测试和指南》要求的报警信号测试系统,对系统的主要组成部分包括视觉和听觉报警信号采集装置、信号转换装置、报警信号处理装置分别作了介绍。针对本标准测试指标繁杂的特点,在报警信号处理过程中引入了智能判定系统,有效提高了报警信号测试的效率和准确性,实现了标准的测试要求。