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11.
Inflammation in nasal and airway tissue caused by allergens, microbial infection, and air pollution are likely to be regulated by inflammatory mediators produced by airway epithelial cells. We have therefore investigated the baseline expression of a number of cytokine genes known to be important inducers and modulators of inflammation, in freshly isolated human nasal epithelium. Cells were obtained by superficial scraping of turbinate tissue, and cDNA for polymerase chain reaction (PCR) amplification was reverse-transcribed directly from lysates of 3 x 10(3) to 5 x 10(3) epithelial cells using random hexamers. Constitutive expression of relatively high levels of interleukin-8 (IL-8) mRNA but undetectable levels (< 1 mRNA copy/cell) of granulocyte/macrophage colony-stimulating factor (GM-CSF), IL-6, IL-1, or tumor necrosis factor (TNF) mRNA were found after PCR amplification of the cDNA. IL-8 protein, but not IL-6, was identified in the nasal epithelial cells by immunocytochemistry. Infection with respiratory syncytial virus (RSV) or stimulation of nasal epithelium for 4 h with TNF or IL-1 in vitro resulted in a 4- to 10-fold increase in IL-8 mRNA expression but not in the expression of detectable levels of mRNA for the other cytokines. IL-8 was secreted by RSV-, IL-1-, and TNF-stimulated as well as unstimulated nasal epithelial cells after 6 to 20 h of culture. Neither IL-6, GM-CSF, nor TNF activity/immunoreactivity was detectable in the culture supernatants. Thus, it appears that IL-8 is a major cytokine of human nasal epithelium, constitutively expressed and readily secreted upon virus infection or stimulation with IL-1 and TNF. 相似文献
12.
The design of specialized processing array architectures, capable of executing any given arbitrary algorithm, is proposed. An approach is adopted in which the algorithm is first represented in the form of a dataflow graph and then mapped onto the specialized processor array. The processors in this array execute the operations included in the corresponding nodes (or subsets of nodes) of the dataflow graph, while regular interconnections of these elements serve as edges of the graph. To speed up the execution, the proposed array allows the generation of computation fronts and their cancellation at a later time, depending on the arriving data operands; thus it is called a data-driven array. The structure of the basic cell and its programming are examined. Some design details are presented for two selected blocks, the instruction memory and the flag array. A scheme for mapping a dataflow graph (program) onto a hexagonally connected array is described and analyzed. Two distinct performance measures-mapping efficiency and array utilization-and some performance results are discussed 相似文献
13.
The authors report measurements of the α-factor and linewidth of DBR (distributed Bragg reflector) lasers fabricated with weak grating constants. Such devices exhibit detuned-loading effects, and the measured values depend strongly on the tuning current of the Bragg section. α-factor behavior is found to agree with earlier theoretical predictions. Linewidth behavior is shown to be dominated by carrier shot noise in the tuning section. A theoretical analysis of the DBR laser is outlined including detuned loading and carrier shot noise effect 相似文献
14.
Raybon G. Young M.G. Koren U. Miller B.I. Chien M. Zirngibl M. Dragone C. Froberg N.M. Burrus C.A. 《Electronics letters》1995,31(14):1147-1149
Five wavelength multiplexed pulse streams are generated in an integrated 16×1 laser modulator array by sinusoidally driving five of the potential 16 electroabsorption modulators. At a repetition rate of 2.5 GHz, near transform-limited pulses spaced in wavelength over 7.6 nm are observed. Pseudorandom coding of one channel is achieved by applying an electrical RZ data signal to the modulator 相似文献
15.
The behavior of a multiprocessing system with a multistage interconnection network is studied in the presence of faulty components. Measures for the connectivity and performance of these systems are proposed, including the average number of operational paths, the average number of accessible processors and memories, the average number of fault-free processors (memories) that are connected to an accessible memory (processor), the bandwidth, and the processing power of the system. Based on these measures, a tight upper bound for the maximal fully connected system is suggested. The gracefully degrading system is then compared, through some numerical examples, to a system whose faulty components are repaired upon failure. Based on these comparisons, the anticipated reduction in system performance can be estimated and consequently, appropriate maintenance policies can be determined 相似文献
16.
Over the last decade, enhanced suffix arrays (ESA) have replaced suffix trees in many applications. Algorithms based on ESAs require less space, while allowing the same time efficiency as those based on suffix trees. However, this is only true when a suffix structure is used as a static index. Suffix trees can be updated faster than suffix arrays, which is a clear advantage in applications that require dynamic indexing. We show that for some dynamic applications a suffix array and the derived LCP-interval tree can be used in such a way that the actual index updates are not necessary. We demonstrate this in the case of grammar text compression with longest first substitution and provide the source code. The proposed algorithm has O(N2) worst case time complexity but runs in O(N) time in practice. 相似文献
17.
eWALL framework, under development in the European eWALL project (project no. 610658: “eWALL for Active Long Living”) is meant for care of population with age related impairments, mild dementia and COPD. Expanded eWALL (e2WALL) is planned to be an integrated quality framework for long-term care services which will cover very different types of care: all healthcare (both preventive and rehabilitative), societal services, care for cognitive diseases, services delivered at home as well as support for caregivers as an integral part of the quality improvement process. Thus, we present e2WALL home system that would encompass installation (setup) of e2WALL in homes (flats, houses and aging homes) and their management and maintenance across Europe, starting from the partners involved in eWALL (Austria, Bulgaria, Croatia, Denmark, Former Yugoslav Republic of Macedonia, Germany, Greece, Italy, Montenegro, The Netherlands and Romania) and expanding the partnership to the most of Europe (e.g. United Kingdom, Poland, Czech Republic…). This would be a direct application of the developed e2WALL platform and should be done through a network of collaborating small-to-medium sized enterprises (SMEs), each of whom would lead the process of setting up e2WALL system and continuing to provide support services to homes in their respective country. In this way, the growth of high tech and innovative SMEs will be ensured at pan European level, which will enable growth over restricted national market and stimulate European investments in SMEs and startups. Actually, the bigger platform will enable e2WALL European Ecosystem (e4WALL), which can then expand into other non-European markets (e.g. Asia, USA) and means sustainability beyond the life of the project. e2WALL will lead to connected tech start-up hubs to the larger European business ecosystem and will contribute to increased access of country-specific and customized new product to the pan European market, which will lead to increase of employed qualified individuals. Another important focus would be creating an energy efficient environment for a new social network where registered users would provide on-demand services. 相似文献
18.
Sixty-six class-II CAD/CAM-manufactured ceramic inlays (Cerec) were placed in 27 patients. Each patient received at least one inlay luted with a dual-cured resin composite and one inlay luted with a chemically cured resin composite. The inlays were examined 5 years after luting using the California Dental Association (CDA) criteria. Eighty-nine percent of the 66 inlays were rated 'satisfactory'. During the follow-up period replacement was required for 3 inlays because of inlay fractures (4.5%) and 1 inlay because of fracture of the tooth substance (1.5%). All those inlays were luted with the dual-cured resin composite luting agent. Of the remaining 62 inlays the CDA rating 'excellent' was given to 84% for color, 97% for surface, and 81% for anatomic form. 'Excellent' margin integrity was seen in 52% of the dual-cured resin composite luted inlays and in 61% of the chemically cured resin composite luted inlays. No statistically significant (P> 0.05) difference was observed between the two luting agents. 相似文献
19.
Hansen P.B. Raybon G. Koren U. Miller B.I. Young M.G. Newkirk M.A. Chien M.-D. Tell B. Burrus C.A. 《Electronics letters》1993,29(7):639-640
An electroabsorption modulator has been monolithically integrated with an extended-cavity laser, which incorporates a Bragg reflector. Actively modelocked at the fundamental cavity resonance frequency of 4.5 GHz, the laser provides a train of 6.3 ps pulses with a centre wavelength of 1544 nm onto which data is encoded by the modulator. This 4.5 Gbit/s single-chip transmitter is suitable for systems employing short optical pulses.<> 相似文献
20.
Yizheng Zhou Lakamraju V. Koren I. Krishna C.M. 《Parallel and Distributed Systems, IEEE Transactions on》2007,18(11):1539-1550
Emerging network technologies have complex network interfaces that have renewed concerns about network reliability. In this paper, we present an effective low-overhead fault tolerance technique to recover from network interface failures. Failure detection is based on a software watchdog timer that detects network processor hangs and a self-testing scheme that detects interface failures other than processor hangs. The proposed self-testing scheme achieves failure detection by periodically directing the control flow to go through only active software modules in order to detect errors that affect instructions in the local memory of the network interface. Our failure recovery is achieved by restoring the state of the network interface using a small backup copy containing just the right amount of information required for complete recovery. The paper shows how this technique can be made to minimize the performance impact to the host system and be completely transparent to the user. 相似文献