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71.
J. Dorn A. Prianichnikova J. Reisinger ÖVE 《e & i Elektrotechnik und Informationstechnik》2001,118(7-8):354-359
In this paper we describe the scheduling of processes, threads and messages for a distributed hard-and software system (for air traffic control) which is supported by heuristics. Furthermore, we show how such application specific heuristics are linked to a reusable application framework. 相似文献
72.
The liberalization of the electricity and telecommunications markets has paved the way for harnessing existing electricity supply networks to transfer data from the low-voltage transformer station right through to every mains socket in a building. Powerline communication (PLC) allows for coupling power supply with data transmission. The modulation or demodulation calls for state-of-the-art, fast chip technologies as well as algorithms. According to powerline companies, the first generation of products is to be launched in the year 2001. Further development of this system depends completely on the regulation of the respective frequency levels. If regulatory measures and the market were to favor powerline technology, electric utility companies could come to play a role as telecom providers. 相似文献
73.
BB rats are used as models of autoimmune human IDDM. Genetic control of IDDM in both species is complex, including both major histocompatibility complex (MHC)-linked and non-MHC-linked genes. DP-BB rats develop IDDM spontaneously. Expression of disease in these animals requires homozygosity at the lyp locus, which causes lymphopenia. All genetic analyses of BB rat diabetes to date have backcrossed to the DP-BB strain or used (DP-BB x non-BB)F2 animals to ensure that a fraction of progeny are homozygous for lyp. Here we report the analysis of a backcross of the DP-BB rat to the histocompatible WF rat. Neither WF nor (WF x DP-BB)F1 animals develop spontaneous IDDM. However, 95% of (WF x DP-BB)F1 rats and a fraction of (WF x DP-BB) x WF backcross animals readily develop IDDM after treatment with polyinosinic:polycytidylic acid and a cytotoxic anti-RT6.1 monoclonal antibody. Using simple sequence length polymorphism analysis, we have mapped loci on chromosomes 4 and 13 that show significant linkage to IDDM expression and insulitis. The susceptibility locus on chromosome 4 is linked to, but not identical to, lyp. We propose a disease model for the BB rat that requires 1) the RT1u MHC haplotype for disease susceptibility, 2) a new locus on chromosome 4 for disease initiation (as measured by insulitis), 3) a new locus on chromosome 13 for disease progression in response to environmental perturbation, and 4) lyp for spontaneous expression of disease. 相似文献
74.
A. Stelzer ÖVE IEEE Ch. G. Diskus IEEE 《e & i Elektrotechnik und Informationstechnik》2001,118(1):8-16
Using microwave technology for industrial sensing applications has the advantage of being insensitive to environmental influences. The presented near range radar has an accuracy of 0.1 mm. This high precision was achieved by using dynamic frequency divider chips for direct frequency measurement and a six-port for phase measurement at 35 GHz. A digital signal processor calculates the distance. 相似文献
75.
NEDJOUA CHEGHIB MOHAMED ABDAOUI THIERRY CRESTEIL GENEVIÈVE AUBERT JEAN-LOUIS KRAUS 《Polycyclic Aromatic Compounds》2013,33(3):143-153
Through the coupling of substituted benzaldehydes with 8-hydroxy 5-amino methyl quinoline scaffold, a series of new derivatives has been synthesized. In vitro growth inhibitory effects on cancer cell line model have been evaluated. Discussion on the chemical reactivity of these new polycyclic aromatic analogs to generate alkylating species led to the hypothesis that the presence of an imine moiety impedes the formation of quinone methide intermediate and consequently abolishes in part their antiproliferative activity. 相似文献
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78.
This study compared the effects of angiotensin converting enzyme (ACE) inhibitors captopril versus enalapril on left ventricular (LV) muscle mass and LV systolic and diastolic function in 58 patients with primary glomerulonephritis and moderate chronic renal failure. The design was a 6-8 week titration phase and 6-month maintenance phase. Mean myocardial mass calculated by M-mode echocardiography in the captopril group was 153 +/- 26 g/m2 before, and 130 +/- 14 g/m2 after 6 months of treatment, in enalapril group 147 +/- 22 g/m2 before, and 126 +/- 23 g/m2 after 6 months of treatment (p < 0.05). LV ejection fraction, early and late transmitral flow velocities and early to late LV inflow velocities ratio were not significantly affected by both ACE inhibitors. 相似文献
79.
The 43 nuclear tests conducted at Enewetak Atoll by the United States between 1948 and 1958 produced close-in fallout that contaminated the islands and lagoon of the atoll with radioactive fission and activation products, and unfissioned nuclear fuel. In 1972, the U.S. government announced that it would conduct a cleanup and restoration operation to return the atoll to the Enewetak people. The radiological cleanup began in 1977 and lasted to 1980 and focused on reducing the concentration of the transuranium elements (238,239,240Pu and 241Am = TRU) in soils on some of the islands that might eventually be used for residence or for subsistence agricultural. The cleanup plan called for relocating soil and some other contaminated debris to Runit Island on the eastern perimeter of the Atoll. Some of the contaminated soil was mixed with cement and the mixture placed below the water level in the Cactus Crater that was formed by a nuclear explosion in 1958. The remainder of the contaminated material was mixed with concrete and placed above ground over the crater in the shape of a dome. A concrete cap was constructed over the dome of soil. Concern has been expressed by the people of Enewetak and by others over the possible aquatic impacts from the radionuclides entombed in the crater. A National Academy of Sciences committee examined the dome and concluded that the containment structure and its contents present no credible health hazard to the people of Enewetak, either now or in the future. The committee suggested that "at least part of the radioactivity contained in the structure is available for transport to the groundwater and subsequently to the lagoon and it is important to determine whether this pathway may be a significant one." Therefore, a surveillance program was started in 1980, in conjunction with other research efforts, to study the radionuclides in samples of fish, groundwater, and lagoon seawater. Our data and conclusions support the findings suggested by the National Academy committee over a decade ago in that any assumption of rapid remobilization of all or any of the dome's transuranics or other radionuclides is an extreme one. Any fear that this structure contains amounts of activity whose release would cause damage to the environment that will result in greater effect on human health is unfounded. 相似文献
80.
MS Cookson PC Sogani P Russo J Sheinfeld H Herr G Dalbagni VE Reuter CB Begg WR Fair 《Canadian Metallurgical Quarterly》1997,79(3):432-438
OBJECTIVES: To assess the pathological staging and biochemical progression-free survival (assessed using serum prostate-specific antigen level) of patients with clinically localized prostate cancer using neoadjuvant androgen deprivation therapy (ADT) in combination with radical retropubic prostatectomy (RRP). PATIENTS AND METHODS: A prospective study was carried out on 69 patients with localized prostate cancer who were enrolled in a trial of 3 months of ADT followed by RRP (group 1). These patients were compared with 72 patients matched for age and clinical stage who declined ADT therapy and had RRP concurrently (group 2). Assignment to the individual treatment groups was thus determined by the patient's preference and not the physician's selection. Pathological staging and biochemical progression-free recurrence were compared between the groups. RESULTS: The rate of organ-confined (pT2) tumours was 74% in group 1 and 49% in group 2 (P < 0.01), and the rate of margin-negative tumours was 87% in group 1 and 64% in group 2 (P < 0.01). Within a median follow-up of 35 months, there was no significant difference in biochemical failure between the groups (P = 0.37). Patients with pT2 disease, regardless of treatment, had similar biochemical failure rates. In the patients with margin-positive disease, there was a significantly higher biochemical failure rate in group 1 (P = 0.02). CONCLUSIONS: The rates of organ- and specimen-confined disease were higher among the patients treated with ADT. The preliminary follow-up suggested that patients with pT2 disease after ADT have a biochemical progression-free recurrence rate similar to pT2 patients treated with RRP alone. Additionally, high biochemical failure rates in patients with margin-positive disease after ADT may identify a subset of more biologically aggressive tumours in need of early adjuvant treatment. 相似文献