Why so many stents?

BETTER THAN ANGIOPLASTY: Prolonging inflation with a perfusion balloon decreases the risk of acute coronary occlusion after angioplasty. The longer the artery remains patent, the greater the chances of 0% residual stenosis. This is what the sent allows. Stent act on both mechanisms of stenosis: elastic recoil and fibrous remodeling of the arterial plaque. TARGETTED ACTION: Stents improve angioplasty prevention of acute stenosis. They have a real action on preventing degeneration of the saphenous graft and lead to a significant reduction in the rate of restenosis of the dilated site. There are however two specific complications: subacute occlusion and greater incidence of vascular events. Stents are particularly indicated for the treatment of restenosis and chronic occlusions. TWO IMPROVEMENTS: Risks related to the implantation of a foreign body in the vascular system have been reduced with the use of ticlopidine and high-pressure stent implantation. POSITIVE RESULTS: Stents have produced better angiographic results. They limit restenosis and the number of revascularizations required in treated patients. Several questions concerning indications remain open.     

Dissociation between peripheral and central heat loss mechanisms induced by neonatal capsaicin.

Peripheral desensitization was induced in 36 2–4 day old Wistar male rats by sc administration of capsaicin in increasing doses (350; 700; 1,400; 2,100; and 2,800 μg) on 5 consecutive days. When adult, 9 treated and 5 control Ss were chronically implanted with a lateral icv guide cannula. This tube was used for icv capsaicin injection. 11 treated Ss and 6 controls were implanted with a hypothalamic thermode. Hypothalamic heating was activated with the aid of this water-perfused thermode. 28 Ss, 12 control and 16 treated, were injected ip and sc with capsaicin. Results show that in control Ss, icv, ip, and sc capsaicin injections produced a fall in body (core) temperature and an increase in cutaneous temperature. These changes are attributed to cutaneous vasodilation. In capsaicin-treated Ss, sc and ip injections had no effect on body temperature. However, neonatal treatment did not inhibit the effect of capsaicin on body temperature. Furthermore, in these Ss thermoregulatory behavior for fresh air was identical to that of controls at all ambient temperatures before and during hypothalamic heating. Results suggest that the central heat receptors responsible for autonomic and behavioral thermoregulation in the treated Ss functioned normally when icv capsaicin was injected or when the hypothalamus was heated. In contrast, neonatal injection of capsaicin produced an inhibition of the heat loss mechanisms induced by ip or sc capsaicin (i.e., by stimulation of the peripheral nervous system). (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Full‐wave analysis of azimuthally magnetized ferrite‐loaded circular structures using the one‐dimensional finite difference frequency domain method

Full‐wave analysis of circular guiding structures completely filled with ferrite by using the finite difference frequency domain method is presented. The ferrite is assumed to be azimuthally magnetized to remanence. Emphasis is placed on the TE_0m modes that are rotationally symmetric. These modes exhibit nonreciprocal behavior that could be exploited to build phase shifters and microwave isolators. Dispersion diagrams for these modes are given for both forward and reverse waves, and the effect of various ferrite parameters is studied. It is shown that the dispersion diagram may exhibit a region of negative slope, which gives rise to backward wave. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009.     

基于时间序列的数据挖掘在证券中的应用

为更好地对股票数据进行分析,从理论上对数据挖掘中时间序列的产生、应用进行了研究,通过对时间序列处理以及相关性搜索的多种方法的比较和分析,设计一个以股票预测为对象的小型系统。该系统首先对时间序列进行适当的处理,然后进行相似性搜索,分析未来的短时间的走势是否是历史上的重现。同时对得到的结果进行了分析,实验结果表明,该方法能找到股票数据中历史上相似走势,并通过历史走势分析当前的走势。     

Design of coplanar waveguide elliptic low pass filters

This article proposes three design topologies of coplanar waveguide elliptic low pass filters. The design procedure is simple and explained in detail for the first topology. Numerical results are provided using the commercially available simulation softwares IE3D and HFSS to show the validity of the design with very good agreement. The proposed filters yield less than 0.1 dB attenuation in the passband (0–2 GHz), with a controllable slope of the transition between passband and stopband. The width of the rejection band is increased by simple filter cascading resulting in a passband to stopband ratio of up to 1:6. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009.     

GFAAS Determination of Zinc in Fish Feed and Feces Using Slurry Sampling

This paper presents a simple, fast, and sensitive method to determine zinc in samples of feces and fish feed by electrothermal atomic absorption spectrometry through the direct introduction of slurries of the samples into the spectrometer’s graphite tube. The procedure is based on the injection of 10 μL of an acidified aqueous solution containing 0.50% w/v of feces or feed and 0.50% v/v HNO₃ into graphite tube. The limits of detection and quantification calculated for 20 readings of the blank of the standard slurries (0.50% w/v of feces or feed devoid of zinc) were 0.04 and 0.13 μg L⁻¹ for the standard feces slurries and 0.05 and 0.17 μg L⁻¹ for the standard feed slurries. The proposed method was applied in studies of digestibility of zinc in different fish feeds, and their results proved compatible with that obtained from samples mineralized by acid digestion using microwave oven.     

New miniature broadband CPW-to-slotline transitions

This paper proposes a novel class of uniplanar coplanar waveguide (CPW)-to-slotline transitions, which is particularly suitable for monolithic millimeter-wave integrated circuits. Instead of using CPW series stub printed in the ground plane, as is the case in classical CPW-to-slotline transition, this paper shows the capability to use a CPW series stub printed in the center conductor of the CPW. Compared to classical CPW-to-slotline transitions, the proposed transitions have the following advantages: additional degrees of freedom, lower radiation loss, larger bandwidth, higher compactness, and a major reduction of the number of air bridges that are potentially expensive to build. One alternative configuration that appears to have some merit involves the use of the slotline ring resonator, which does not suffer from open-end or short-end effects and, therefore, gives more accurate resonance frequency, provides an accurate localized zero or infinite impedance point, and maintains low- or high-input impedance values over a wide frequency range, depending on the feed type. A principle of achieving such high-quality transitions is detailed and also confirmed by experimental and theoretical results, which are in good agreement up to 50 GHz. A maximum fractional bandwidth of 160% is achieved for a 10-dB return loss, and the corresponding insertion loss is less than or equal to 2 dB     

Theoretical and experimental characterization of coplanar waveguidediscontinuities for filter applications

A full-wave analysis of shielded coplanar waveguide (CPW) two-port discontinuities based on the solution of an appropriate surface integral equation in the space domain is presented. Frequency-dependent scattering parameters for open-end and short-end CPW stubs are computed using this method. The numerically derived results are compared with measurements performed in the frequency range 5-25 GHz and show very good agreement. From the scattering parameters, lumped-element equivalent circuits have been derived to model the discontinuities. The inductors and capacitors of these models have been represented by closed-form equations, as functions of the stub length, to compute the circuit element values for these discontinuities     

Chronic recurrent transverse myelitis or multiple sclerosis

Electron microscopy of HEp-2 cells infected with respiratory syncytial virus (RSV) strain Long revealed the maturation of RSV on an ultrastructural level. The results showed that the virus maturated by two different pathways. In one of them, the virus assembled and matured before reaching the plasma membrane on the internal vesicle membrane within cytoplasm. The mature virus was delivered to the plasma membrane and to the extracellular space most likely by the transport vesicles and exocytosis. In the other pathway, the virus matured on the plasma membrane as described with other members of the family Paramyxoviridae. Using monoclonal antibodies (MoAbs), we localized viral nucleoprotein (NP) and envelope proteins in cytoplasm by immunoelectron microscopy (IEM).     

Doppler-derived pulmonary arterial systolic pressure in patients with known systemic arterial pressures

In the present study, we evaluated Doppler-derived systolic pulmonary artery pressure in 476 hypertensive patients. Clinical interpretation of systolic pulmonary arterial pressure should take into account age, body size, and systolic blood pressure values.