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11.
This commmunication describes some current applications tions of adaptive filtering to the processing of microwave Doppler signals for heart rate monitoring. The problem has been approached in the past using signal processing techniques such as peak detection or autocorrelation. These methods either require large amounts of data or tend to be unreliable. This communication utilizes some recent techniques used in speech processing and applies them to heartbeat detection, thus allowing on-line processing of sampled microwave heart signals. The presentation includes a model for the signal, brief discussions of the algorithms evaluated, and qualitative analysis of performance compared to EKG measurements.  相似文献   
12.
Energy is the most abundant and valuable natural resource of Central Asia and northwest China1 and includes oil, gas, coal, electricity, and renewables. Kazakhstan has large reserves of oil and coal. Turkmenistan and Uzbekistan have significant reserves of gas. Kyrgyzstan produces significant amounts of hydroelectric power. Xinjiang, China has significant coal resources and an uncertain, although generally promising, potential for oil in the Tarim basin. These energy reserves form the basis for future economic growth and development in the region, and energy exports are beginning to generate important foreign exchange revenues. Although Central Asia enjoys vast energy development potential, there are obstacles to exploiting these resources, including limited infrastructure for transporting energy—notably oil and gas pipelines and electric transmission lines—in the region, political turmoil, payment difficulties, and inadequate energy policies. Despite these challenges, however, with appropriate government planning Central Asia is poised to become a significant world supplier of energy, especially in the oil and gas sectors, and the region is likely to diminish OPEC's influence of the global oil market over the long term.  相似文献   
13.
Aggressive pursuit of high-quality health care had guided the Health Service of the United States Army to establish a labor analgesia program within its hospitals. A dedicated Labor Epidural Service can be quite expensive, especially from the manpower standpoint. Therefore, the Anesthesia Service at Reynolds Army Community Hospital, Fort Sill, Oklahoma, implemented a program of intrathecal narcotic injection as an alternative to costly labor epidural analgesia. After reviewing a patient fact sheet, 150 laboring patients volunteered for labor intrathecal analgesia (LIA). Once active labor began, the patient received intrathecal morphine (0.25 mg) and fentanyl (25 micrograms). The pain level before and after the LIA was evaluated by the visual analog schedule method. At 2 weeks follow-up the intrathecal narcotic-assisted labor was subjectively reported by the patients. Ninety-four percent of the patients agreed that the LIA worked well and that they would do it again. LIA was found to be a well-accepted, cost-saving, very effective approach to labor analgesia.  相似文献   
14.
From a database of 130 implantable cardiac defibrillator recipients, 2 patients (1.5%) with sudden cardiac death as a presenting symptom, leading to diagnosis of primary hyperaldosteronism, are described. This is a newly described cause of sudden cardiac death, possibly more frequent than suspected, which should be considered in patients with malignant arrhythmias and hypokalemia.  相似文献   
15.
The aim of this study was to develop a technique for separating monocytic cells in suspension from peripheral blood to measure the intracellular penetration of three fluoroquinolones (ofloxacin, ciprofloxacin and sparfloxacin). Mononucleated cells were isolated from the blood on a density gradient with lymphoprep and purified by a specific technique of adhesion and disadhesion on fibronectin. The monocytes were obtained in suspension with 76.8% purity and 97.9% viability. This was a convenient form for measurement of intracellular accumulation by use of the velocity-centrifugation technique. Intra-monocytic penetration of ciprofloxacin, ofloxacin and sparfloxacin was measured at equilibrium after 30-min incubation in the presence of 16 microg mL(-1) antibiotic. The results revealed low intra-monocytic accumulation of ciprofloxacin (intracellular-extracellular = 1.76) and ofloxacin (intracellular-extracellular = 1.42). The penetration of sparfloxacin was significantly higher (intracellular-extracellular = 2.4). This study confirms the important differences between human immunocompetent cells in terms of their ability to concentrate quinolones. It also underlines the importance of monocyte-macrophage cellular differentiation as a determinant of antibiotic penetration.  相似文献   
16.
正科帕卡格拉纳位于新多瑙河12.5公里处,毗邻Reichsbrücke大桥。出于同旧有设计保持协调性考虑,力求能让大楼融入当地环境,迎合自身功能性需要,GERNER GERNER PLUS团队充分考虑现有周边环境,对大楼重新规划设计。新的设计突显建筑的特殊性和重要性,面向河流的立面是科帕卡格拉纳大楼最重要的部分,所以设计的重点也放在了这里。现有的城市中轴线是一个参照物,为了视觉上和氛围上形成一体化城市的感  相似文献   
17.
Nanoparticle‐based voluminous 3D networks with low densities are a unique class of materials and are commonly known as aerogels. Due to the high surface‐to‐volume ratio, aerogels and xerogels might be suitable materials for applications in different fields, e.g. photocatalysis, catalysis, or sensing. One major difficulty in the handling of nanoparticle‐based aerogels and xerogels is the defined patterning of these structures on different substrates and surfaces. The automated manufacturing of nanoparticle‐based aerogel‐ or xerogel‐coated electrodes can easily be realized via inkjet printing. The main focus of this work is the implementation of the standard nanoparticle‐based gelation process in a commercial inkjet printing system. By simultaneously printing semiconductor nanoparticles and a destabilization agent, a 3D network on a conducting and transparent surface is obtained. First spectro‐electrochemical measurements are recorded to investigate the charge–carrier mobility within these 3D semiconductor‐based xerogel networks.  相似文献   
18.
The article provides a unique opportunity to study a large white‐clawed crayfish mitigation exercise on the River Wansbeck, Northumberland in North East England. The translation was necessary to allow the construction of a dam on the river to reduce flood risk to the town of Morpeth. The study provides an assessment of the methodology used for the capture and translocation activities, and provides an insight into the speed of colonisation and population establishment in a 300‐m diversion channel and the structure of translocated populations. Over 3500 + white‐clawed crayfish were caught when the natural channel was dewatered, with 5400 animals removed the following year when the diversion channel was closed. Average density based on the number of white‐clawed crayfish caught was estimated as in excess of 5 per 1 m2. The study demonstrates the importance of the River Wansbeck for white‐clawed crayfish.  相似文献   
19.
Nondestructive evaluation of thermal barrier coating (TBC) degradation during service operation has received a wide attention for service life prediction of advanced gas turbines. In this work, TBC on nickel base superalloy degraded at various degrees by thermal aging is investigated. Particularly, TBC and Metal–Chromium–Aluminum–Yttrium alloy (McrAlY) (M indicates iron (Fe), cobalt (Co), nickel (Ni) or these combinations) bond coating interface where a detrimental reaction takes place and forms various reaction products during thermal aging, is studied in detail. Formation kinetics and physical properties of the reaction layer are evaluated by means of Impedance Spectroscopy (IS). Specimens aged at higher temperature and a longer aging time shows larger impedance. The impedance behavior of TBC and bond coating is found to be markedly changed by the formation of the reaction layer. Physical properties and thickness of the reaction layer are evaluated using the change of the impedance. A mechanistic interpretation of the cause of change in the physical properties and IS behavior are described.  相似文献   
20.
An anthracenyl‐modified chiral bis(oxazoline) copper complex has been demonstrated to efficiently promote nitroaldol reactions between structurally varying aldehydes and nitromethane or nitroethane. The catalyst was recovered through formation of a charge transfer complex between the chiral ligand and trinitrofluorenone and its subsequent precipitation with pentane. The efficiency of this procedure was proved through several consecutive catalytic cycles that allowed the sturdy formation of the expected product with a high enantioselectivity. The catalyst′s stability was also put to the test in an original multi‐substrate procedure. Following the same recovery concept, a new heterogeneous procedure was tested for which trinitrofluorenone was covalently linked to a silica support. Asymmetric heterogeneous catalysis was performed under these conditions as one of the few examples demonstrating the potential catalyst recycling in nitroaldol reactions through reversible, non‐covalent interactions.  相似文献   
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