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71.
Beach Mark Bourse Didier Dillinger Markus Falk Rainer Farnham Tim Navarro-Prieto Raquel Wiebke Thomas 《电信纪事》2002,57(7-8):653-676
To date, research into reconfigurable mobile communications has predominantly focussed on the software radio concept, and specifically on the hardware technologies required to move physical layer processing into a programmable environment [1, 2, 3]. Although an interesting and necessary challenge, this only represents a fraction of the overall support and technology required to realise the potential of the concept. Other necessary developments include network/terminal cooperation for seamless inter-standard handoff, QoS management for software download and reconfiguration, a secure software download mechanism, terminal software and mobile radio network architecture supporting terminal reconfiguration, management for software downloads, configuration management, capability negotiation, radio resource management and spectrum allocation policies etc… This paper describes results from the EuropeanIst Trust (Transparently Reconfigurable UbiquitouS Terminal) [4] project concerning user and operator requirements, the proposed overall system environment, security issues, concerted radio resource management, and expected time frame for the development of reconfigurable terminals. 相似文献
72.
Pérez Conesa D Ros Berruezo G Periago Castón MJ 《Archivos latinoamericanos de nutrición》2002,52(2):193-202
The effect of technological process on essential and non essential amino acids contents in infant cereals, the protein and essential amino acids infant dietary requirements cover by infant cereals, and its quality using some chemical scores has been studied. Mix of raw flours, mix of roasted flours, mix of enzymatically, hydrolysed and drum dried flours and commercial infant cereals of four different types of infant cereals: "Multicereal" and "Wheat" (both with gluten), "Growth" and "Rice and carrot" (both gluten free) were evaluated. The technological process only show a significant effect on lysine, arginine (P < 0.05) and valine (P < 0.01) contents in "Rice and carrot" infant cereal. Protein of any studied infant cereals covers 17.4% of the daily infant requirements in, while for essential amino acids will cover about 25 to 200% until the third year of life. As we expected, the limitant amino acid was lysine in all flours. Chemical scores only were affected by technological treatment in "Rice and carrot" infant cereal, showing the gluten-free infant cereals higher values (36.7-69.5%) than gluten infant cereals (18.1%-30.7%) at the end of the processing. It should be standing out "Growth" infant cereal, because of it has a higher lysine content than other infant cereals due to the main ingredients rice and corn. 相似文献
73.
Study of the aromatic by-products formed from ozonation of anilines in aqueous solution 总被引:6,自引:0,他引:6
Aqueous solutions of aniline and p-chloroaniline were treated with ozone in order to study the reaction and oxidation by-products. Aniline solutions were ozonated at low and high pH, so as to compare both molecular and hydroxyl free radical mechanisms, respectively. The main identified aromatic by-products were nitrobenzene and azobenzene when the experiment was carried out at acid pH. Formation of nitrobenzene, azobenzene, azoxybenzene and 2-pyridine-carboxylic was observed when the ozonation was carried out at basic pH. p-Chloroaniline was treated with ozone only at high pH and the identified by-products were in accordance with those obtained in the ozonation of aniline: p-chloronitrobenzene, 4,4'-dichloroazobenzene and 4-chloro-2-pyridine-carboxylic acid. All the aromatic by-products found were less toxic than the raw materials. The pseudo-first-order constants in aniline concentration were calculated, whilst kinetic in p-chloroaniline concentration could not be adjusted to a first-order reaction. 相似文献
74.
Some accurate glow curve fitting functions for general and mixed order kinetics glow peaks are proposed and discussed. These mathematical expressions are used together with peak search and non-linear minimisation algorithms in order to provide a fast glow curve deconvolution for those materials which cannot be well fitted using first order kinetics. To test the accuracy of the proposed method. the result of the fitting of synthetic glow curves is compared with the original data giving negligible errors for values of parameters currently found in TL materials. 相似文献
75.
Table of Contents
Forthcoming Contributions 相似文献76.
Klibanoff Raquel S.; Levine Susan C.; Huttenlocher Janellen; Vasilyeva Marina; Hedges Larry V. 《Canadian Metallurgical Quarterly》2006,42(1):59
This study examined the relation between the amount of mathematical input in the speech of preschool or day-care teachers and the growth of children's conventional mathematical knowledge over the school year. Three main findings emerged. First, there were marked individual differences in children's conventional mathematical knowledge by 4 years of age that were associated with socioeconomic status. Second, there were dramatic differences in the amount of math-related talk teachers provided. Third, and most important, the amount of teachers' math-related talk was significantly related to the growth of preschoolers' conventional mathematical knowledge over the school year but was unrelated to their math knowledge at the start of the school year. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Macedo Carlos Eduardo; Martinez Raquel Chacon Ruiz; Brand?o Marcus Lira 《Canadian Metallurgical Quarterly》2006,120(3):625
Chemical stimulation of the inferior colliculus (IC) with semicarbazide--an inhibitor of the gamma aminobutyric acid synthesizing enzyme--functions as an unconditioned stimulus in the conditioned place aversion test (CPA), and electrolytic lesions of the basolateral amygdala (BLA) enhance the aversiveness of the IC stimulation. This study examined the effects of inactivation of the BLA with muscimol on the conditioned and unconditioned fear using semicarbazide injections into the IC of rats subjected to conditioned (CPA) or unconditioned (open field) fear tests. In both tests, the rats were injected with semicarbazide or saline into the IC and muscimol or saline into the BLA. Muscimol decreased the CPA and increased the unconditioned fear elicited by IC injections of semicarbazide. These findings indicate that distinct modulatory mechanisms in the BLA are recruited during the conditioned and unconditioned fear triggered by IC activation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
J Carratalà B Rosón A Fernández-Sevilla F Alcaide F Gudiol 《Canadian Metallurgical Quarterly》1998,158(8):868-872
BACKGROUND: Bacteremic pneumonia is a major cause of death among neutropenic patients with cancer. METHODS: We analyzed the causes, empirical antibiotic therapy, and outcome of 40 consecutive cases of bacteremic pneumonia identified among 408 episodes of bacteremia in adult neutropenic patients with cancer, prospectively documented from 1986 to 1995. RESULTS: The most frequent causative organisms were Pseudomonas aeruginosa (17 cases), Streptococcus pneumoniae (12 cases), Escherichia coli (5 cases), and Streptococcus mitis (3 cases). Overall, P. aeruginosa and S. pneumoniae caused 72.5% of all episodes of bacteremic pneumonia, compared with 11.4% of bacteremic episodes from other sources (P< .001). Thirty patients received ceftazidime and 10 patients received imipenem as the beta-lactam component of the initial empirical treatment. All strains of P. aeruginosa were susceptible to both agents. Forty-seven percent of streptococcal strains were penicillin resistant and showed a decreased susceptibility to ceftazidime (minimum inhibitory concentration ranged from 1 to 64 microg/mL). Five patients (12.5%) were considered to have received inappropriate empirical antibiotic therapy. Attributable mortality in patients with bacteremic pneumonia was higher than in patients with bacteremia from other sources; 22 (55%) of the 40 patients with bacteremic pneumonia died, whereas 39 (10.6%) of the 368 patients with bacteremia from other sources died (P<.001). CONCLUSIONS: Our data suggest that bacteremic pneumonia in neutropenic cancer patients is associated with a poor outcome and that empirical antibiotic therapy for neutropenic patients with pneumonia should include agents active against both P. aeruginosa and cephalosporin-resistant streptococci. 相似文献
79.
Pitx2 participates in the late phase of the pathway controlling left-right asymmetry 总被引:1,自引:0,他引:1
ME Piedra JM Icardo M Albajar JC Rodriguez-Rey MA Ros 《Canadian Metallurgical Quarterly》1998,94(3):319-324
BACKGROUND: We have studied the role of the different MHC (RT1) subregions in acute natural killer (NK) cell-mediated bone marrow allograft rejection in lethally irradiated, bone marrow cell (BMC) reconstituted rats. METHODS: We employed a series of MHC congenic and intra-MHC recombinant rat strains so that effects of mismatches in defined RT1 subregions could be studied systematically. BMC allograft survival was measured as 125IUdR uptake in the spleen between day 5 and day 7 after irradiation and BMC reconstitution. RESULTS: We found that in certain RT1 haplotype combinations, nonclassical RT1.C disparities by themselves could determine graft rejection (i.e., in the u/av1 recombinant haplotypes), whereas in another combination (between the av1 and c haplotypes) a mismatch for an isolated classical RT1.A region was decisive for engraftment. Thus, PVG.R1 BMC failed to proliferate in PVG rats, differing in the RT1.A region only, whereas in PVG.1U rats rejection could be determined by isolated differences in the RT1.C region (LEW.1WR1). Also, RT1 homozygous rats (RT1.U) rejected semi-allogeneic F1 hybrid BMC. The acute rejection of BMC was mediated by NK cells, as athymic nude rats, lacking alloreactive T cells but with normal alloreactive NK cells, showed the same patterns of rejection as did normal rats. Nude rats also rejected allogeneic lymphocytes, a previously documented NK-mediated phenomenon, with identical requirements of MHC disparity. CONCLUSIONS: This investigation shows that rat effector NK cells are radioresistant, independent of the thymus, and capable of recognizing and rejecting MHC mismatched transplanted BMC on the basis of mismatches in both classical and nonclassical class I regions in vivo. The studies underline the importance also of NK cells in determining BMC allograft survival. 相似文献
80.
M U?cinowicz M Kaczmarski M Szczepański J Wasilewska K Ros?an B Zapolska E Solarz 《Canadian Metallurgical Quarterly》1995,40(3):561-567
The frequency of erythrocyturia in children with diagnosed food allergy was evaluated. The analysed clinical and immunological allergic process indicators and one year's observation confirm the allergic background of erythrocyturia in 2.6% of the examined group. There are indications for an elimination diet and the application of anti-allergic treatment in the above cases. 相似文献