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1.
The authors describe the cases of two women suffering from AL amyloidosis with affection of the heart muscle in particular. In one of the patients there were also massive amyloid deposits in the lungs which is an exceptional finding. The observations confirm the adverse prognosis of amyloidosis, the rapid progression of the disease after the onset of symptoms of cardiac failure. The first cardial manifestation in both patients were palpitations. The first patient, but not the second one, had a myeloma confirmed on necropsy.  相似文献   
2.
Internet information services replicate their servers to improve availability, response time, and fault tolerance. Traditional replication algorithms do not address the scale and administrative decentralization of today's internetworks. We have proposed and implemented a scalable and efficient tool to replicate wide-area, autonomously managed services. We target replication degrees of thousands of weakly consistent replicas. The main goal of our replication tool is to make traditional replication services scale in today's exponentially growing, autonomously managed internetworks. Our tool, which we call flood-d, allows servers to be organized in multiple replication groups. For each replication group, flood-d builds a logical update topology that is resilient to server failure, and tries to minimize the communication cost and propagation time needed to transmit updates. Flood-d's logical topologies are computed based on communication latency and available network bandwidth. This paper describes flood-d, and presents simulation results obtained when using flood-d to extend existing replication algorithms. Our results show the gains of organizing service replicas into multiple, smaller replication groups, and using network-cognizant logical topologies to propagate updates. We argue that existing as well as emerging Internet information services can benefit from flood-d's services  相似文献   
3.
Summary Soybean fatty acids were conjugated with alkali, and the contained, conjugated dienoic acids were isomerized with iodine to thetrans,trans configuration. Adducts were prepared from thesetrans,trans-conjugated acids by condensation with maleic anhydride and acrylic acid. The adducts were isolated, purified, and converted to esters by using a variety of alcohols, including methyl, ethyl,n-propyl,n-butyl, and allyl alcohols. Esters made from saturated alcohols were converted into the corresponding epoxy derivatives. All of the esters (except allyl) and all of the epoxy esters were compatible with an equal weight of polyvinyl chloride and appeared to be primary plasticizers for this plastic. The epoxy esters were effective in inhibiting heat deterioration of polyvinyl chloride. Presented at fall meeting. American Oil Chemists' Society, September 23–26, 1956, Chicago, Ill.  相似文献   
4.
Summary Adducts of dienophiles and alkali-conjugated safflower fatty acids containing conjugated linoleic acid in thecis,trans form were prepared by heating the reactants in the presence of selenium as a catalyst. The products appeared to be identical to those prepared fromtrans,trans conjugated linoleic acid so that isomerization ofcis-trans totrans,trans acids is eliminated as a separate step. Although yields of pure product were lower than desired because of difficulties in removing selenium, yields of crude adducts ranged from 64–82%. The adducts obtained could be epoxidized with hydrogen peroxide and an ion-exchange resin as catalyst in 80–93% yield or with peracetic acid in 89–98% yield. Presented at the meeting of the American Oil Chemists' Society, Cincinnati. O. September 30–October 2, 1957.  相似文献   
5.

We measured the dissipation resulting from internal friction in hcp solid 4He at temperatures between 0.8 K and 2.5 K. Solid 4He is contained inside an annular metal cell forming a part of a torsional oscillator. An oscillatory motion of the cell walls applies shear stress on the solid 4He. The resulting shear strain within the solid 4He generates dissipation because of the internal friction. The experimental sensitivity was high enough to detect dissipation caused by internal friction associated with elementary excitations of the solid. At temperatures below 1.6 K, internal friction is associated with diffusion of single point defects responsible for the climb of dislocations. At higher temperatures, the main mechanism of internal friction appears to be associated with phonon exchange between parts of the solid moving relative to each other under the applied shear stress. This particular dissipative mechanism was called “quantum phonon friction” [Popov in Phys. Rev. Lett. 83:1632–1635, 1999]. The physical mechanism associated with this type of friction involves an irreversible transfer of momentum from the phonons to the lattice via an Umklapp process. Our data are in a very good agreement with this model.

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6.
Analyses a multiround flow control algorithm that attempts to minimize the time required to multicast a message to a group of recipients and receive responses directly from each group member. Such a flow control algorithm may be necessary because the hurry of responses to the multicast can overflow the buffer space of the process that issued the multicast. The condition that each recipient directly respond to the multicast prevents the use of reliable multicast protocols based on software combining trees or negative-acknowledgments. The flow control analysed algorithm directs the responding processes to hold their responses for some period of time, called the backoff time, before sending them to the originator. The backoff time depends on the number of recipients that respond, the originator's available buffer space and buffer service time distribution, and the number of times that the originator is willing to retransmit its message. This paper develops an approximate analysis of the service time distribution of the limited-buffer preemptive queuing process that occurs within the protocol processing layers of a multiprogrammed operating system. It then uses this model to calculate multicast backoff times. The paper reports experimental verification of the accuracy of this service time model and discusses its application to the multicast flow control problem  相似文献   
7.
Obraczka  K. Danzig  P.B. Li  S.-H. 《Computer》1993,26(9):8-22
An overview of resource discovery services currently available on the Internet is presented. The authors concentrate on the following discovery tools: the Wide Area Information Servers (WAIS) project, Archie, Prospero, Gopher. The World-Wide Web (WWW), Netfind, the X.500 directory, Indie, the Knowbot Information Service (KIS), Alex, Semantic File Systems, and Nomenclator. The authors summarize the surveyed tools by presenting a taxonomy of their characteristics and design decisions. They also describe where to find and how to access several of the surveyed discovery services. They conclude with a discussion of future directions in the area of resource discovery and retrieval  相似文献   
8.
Many designs for integrated services networks offer a bounded delay packet delivery service to support real-time applications. To provide a bounded delay service, networks must use admission control to regulate their load. Previous work on admission control mainly focused on algorithms that compute the worst case theoretical queueing delay to guarantee an absolute delay bound for all packets. In this paper, we describe a measurement-based admission control algorithm (ACA) for predictive service, which allows occasional delay violations. We have tested our algorithm through simulations on a wide variety of network topologies and driven with various source models, including some that exhibit long-range dependence, both in themselves and in their aggregation. Our simulation results suggest that measurement-based approach combined with the relaxed service commitment of predictive service enables us to achieve a high level of network utilization while still reliably meeting the delay bound  相似文献   
9.
BACKGROUND: Extracorporeal shock wave lithotripsy is relatively contraindicated in patients with an implanted cardiac pacemaker. Shock waves can damage the pacemaker by mechanical pressure and also by electromagnetic induction. Since the distance between the applicator and the pacemaker is small during biliary lithotripsy, the risk of damaging the pacemaker is greater. In the following case, the patient presented with a stone in the common bile duct, and had an implanted pacemaker. Lithotripsy with non-synchronized shock waves was the method of choice since conventional surgery was high risk in this specific case. CASE REPORT: In an 84-year-old woman with a stone in the proximal part of the common bile duct, endoscopic attempts of extraction failed. Therefore, shock wave lithotripsy was indicated. This patient had serious heart disease with an interference of spontaneous heart action with the pacemaker at a ratio of 1:1. We decided to treat with shock wave lithotripsy. The application of shock waves was without side effects on the patient and the pacemaker. CONCLUSION: This case is interesting as it highlights the possibility of using the Czech made MEDILIT lithotriptor in the treatment of choledocholitiasis in patients with a pacemaker. Even so, it is necessary to monitor the patient's ECG to ensure the possibility of immediate external stimulation.  相似文献   
10.
An information-filtering system collects incoming data of specific interests described in a server profile. These systems can export their collections by submitting their profiles to a directory server, where users can query for relevant systems to answer their requests. We develop a new similarity measure to rank information-filtering systems for Boolean queries. Users can send queries to the top-ranked systems and obtain most of the relevant information. In contrast to an existing method developed by Radecki, our method requires less time and space complexity and has better recall and precision for higher-ranked systems.  相似文献   
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