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31.
BACKGROUND: Serum amyloid A (SAA) proteins are a family of inflammatory apolipoproteins that may modify high-density lipoprotein structure and function. Elevations of SAA have been reported in unstable coronary syndromes, but the levels and types of SAA protein in humans with spontaneous or transplant-associated coronary artery disease are not known. METHODS AND RESULTS: SAA levels were analyzed using an ELISA in 76 sera from 36 patients after cardiac transplantation and in 346 other individuals, 85 patients with atherosclerotic coronary disease plus 261 of their relatives. The mean SAA level was 5-fold higher in transplant patients (203+/-181 microg/mL [23 to 934 microg/mL]) compared with normal subjects without coronary disease (36+/-16 microg/mL [2.8 to 193 microg/mL], P<.005). The mean SAA level was significantly elevated in patients with transplant coronary disease (206+/-160 microg/mL, n=23) compared with those without (140+/-104 microg/mL, n=12, P=.02). Elevated SAA levels were associated with increased mortality after transplantation. On multiple regression analysis, SAA levels were predicted by corticosteroid dose, pretransplant diagnosis of atherosclerotic coronary artery disease, and the presence of transplant coronary disease. SAA levels were elevated in patients with spontaneous atherosclerotic coronary disease (49+/-31 microg/mL) compared with unaffected relatives (39+/-36 microg/mL, mean+/-SD, P=.02). There was no evidence for a genetic contribution to SAA levels. All inducible human SAA protein types were documented by immunoblotting in both spontaneous and transplant coronary disease. CONCLUSIONS: Environmentally determined elevations in SAA levels in patients with both spontaneous and transplant coronary artery disease provide further evidence for a potential pathophysiological link between inflammation, lipoprotein metabolism, and the development of atherosclerosis.  相似文献   
32.
Containment structures such as bins and tanks commonly consist of an elevated cylindrical vessel with a conical closure at the base. The complete structure is typically supported by a ringbeam placed at the intersection of the cylinder and cone, and this in turn is supported on columns. In this paper, a comparative study is made of three ringbeam geometries under radial and vertical loading. The axial, flexural, torsional and distortional responses of the ringbeams are modelled by treating the ringbeam as an assembly of axisymmetric shells. The behaviour is shown to be complex and the stresses are found to be poorly described by existing ringbeam design methods.  相似文献   
33.
McNeill (1985) claimed that speech and its accompanying gestures "share a common computational stage" that is located early in the speech production process. This position depends on two crucial arguments that we believe are unsound: first, that gestures "are synchronized with linguistic units in speech" and, second, that gestures "have semantic and pragmatic functions that parallel those of speech." Careful analysis of the relevant data indicated that although the processes underlying gestural production are globally autonomous, they are linked to speech production at more than just one computational stage. An account is offered that explicates these links. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
34.
The effect of radio-frequency (RF) or low-frequency (LF) bias voltage on the for- mation of amorphous hydrogenated carbon (a-C:H) films was studied on silicon substrates with a low methane (CH4) concentration (2-10 vol.%) in CH4+Ar mixtures. The bias substrate was applied either by RF (13.56 MHz) or by LF (150 kHz) power supply. The highest hardness values (~18-22 GPa) with lower hydrogen content in the fihns (~20 at.%) deposited at 10 vol.% CH4, was achieved by using the RF bias, However, the films deposited using the LF bias, under similar RF plasma generation power and CH4 concentration (50 W and 10 vol.%, respectively), displayed lower hardness (~6-12 GPa) with high hydrogen content (~40 at.%). The structures analyzed by Fourier Transform Infrared (FTIR) and Raman scattering measurements provide an indication of trans-polyacetylene structure formation. However, its excessive formation in the films deposited by the LF bias method is consistent with its higher bonded hydrogen concentration and low level of hardness, as compared to the film prepared by the RF bias method. It was found that the effect of RF bias on the film structure and properties is stronger than the effect of the low-frequency (LF) bias under identical radio-frequency (RF) powered electrode and identical PECVD (plasma enhanced chemical vapor deposition) system configuration.  相似文献   
35.
We report direct optical observation of cavitation bubbles in liquid helium, both in classical viscous He I and in superfluid He II, close to the \(\lambda \)-transition. Heterogenous cavitation due to the fast-flowing liquid over the rough surface of prongs of a quartz tuning fork oscillating at its fundamental resonant frequency of \(4\,\mathrm {kHz}\) occurs in the form of a cluster of small bubbles rapidly changing its size and position. In accord with previous investigators, we find the cavitation threshold lower in He I than in He II. In He I, the detached bubbles last longer than one camera frame (10 ms), while in He II the cavitation bubbles do not tear off from the surface of the fork up to the highest attainable drive.  相似文献   
36.
Yet Another Resource Negotiator (YARN) is a framework to manage and allocate resource requests from applications that process big data stored in HDFS. However, dynamic power management methods are not efficient when YARN manage applications to process big data stored in the default data layout of HDFS. In this paper, we propose a new data layout scheme that can be implemented for HDFS. A comparison between our proposal and the existing HDFS data layout scheme shows that the new data layout algorithm significantly reduces the energy consumption at the slight expense of the mean response time of jobs.  相似文献   
37.
The increasing demand for video streaming services with a high Quality of Experience (QoE) has prompted considerable research on client-side adaptation logic approaches. However, most algorithms use the client’s previous download experience and do not use a crowd knowledge database generated by users of a professional service. We propose a new crowd algorithm that maximizes the QoE. We evaluate our algorithm against state-of-the-art algorithms on large, real-life, crowdsourcing datasets. There are six datasets, each of which contains samples of a single operator (T-Mobile, AT&T or Verizon) from a single road (I100 or I405). All measurements were from Android cellphones. The datasets were provided by WeFi LTD and are public for academic users. Our new algorithm outperforms all other methods in terms of QoE (eMOS).  相似文献   
38.

We present Assume-Guarantee-Repair (AGR)—a novel framework which verifies that a program satisfies a set of properties and also repairs the program in case the verification fails. We consider communicating programs—these are simple C-like programs, extended with synchronous actions over communication channels. Our method, which consists of a learning-based approach to assume–guarantee reasoning, performs verification and repair simultaneously: in every iteration, AGR either makes another step towards proving that the (current) system satisfies the required properties, or alters the system in a way that brings it closer to satisfying the properties. To handle infinite-state systems we build finite abstractions, for which we check the satisfaction of complex properties that contain first-order constraints, using both syntactic and semantic-aware methods. We implemented AGR and evaluated it on various communication protocols. Our experiments present compact proofs of correctness and quick repairs.

  相似文献   
39.
40.
Gil Y  Rotter N  Arnon S 《Applied optics》2012,51(18):4232-4239
There is an increasing demand for transdermal high-data-rate communication for use with in-body devices, such as pacemakers, smart prostheses, neural signals processors at the brain interface, and cameras acting as artificial eyes as well as for collecting signals generated within the human body. Prominent requirements of these communication systems include (1) wireless modality, (2) noise immunity and (3) ultra-low-power consumption for the in-body device. Today, the common wireless methods for transdermal communication are based on communication at radio frequencies, electrical induction, or acoustic waves. In this paper, we will explore another alternative to these methods--optical wireless communication (OWC)--for which modulated light carries the information. The main advantages of OWC in transdermal communication, by comparison to the other methods, are the high data rates and immunity to external interference availed, which combine to make it a promising technology for next-generation systems. In this paper, we present a mathematical model and experimental results of measurements from direct link and retroreflection link configurations with Gallus gallus domesticus derma as the transdermal channel. The main conclusion from this work is that an OWC link is an attractive communication solution in medical applications. For a modulating retroreflective link to become a competitive solution in comparison with a direct link, low-energy-consumption modulating retroreflectors should be developed.  相似文献   
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