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1.
On the capacities of bipartite Hamiltonians and unitary gates 总被引:2,自引:0,他引:2
Bennett C.H. Harrow A.W. Leung D.W. Smolin J.A. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2003,49(8):1895-1911
We consider interactions as bidirectional channels. We investigate the capacities for interaction Hamiltonians and nonlocal unitary gates to generate entanglement and transmit classical information. We give analytic expressions for the entanglement generating capacity and entanglement-assisted one-way classical communication capacity of interactions, and show that these quantities are additive, so that the asymptotic capacities equal the corresponding 1-shot capacities. We give general bounds on other capacities, discuss some examples, and conclude with some open questions. 相似文献
2.
DH Kang CL Coe DO McCarthy NN Jarjour EA Kelly RR Rodriguez WW Busse 《Canadian Metallurgical Quarterly》1997,17(8):481-487
T cell cytokines play an important role in mediating airway inflammation in asthma. The predominance of a Th2 cytokine profile, particularly interleukin (IL)-4 and IL-5, is associated with the pathogenesis and course of asthma. The aim of this study was to test the hypothesis that a stressful life event alters the pattern of cytokine release in asthmatic individuals. Thirteen healthy controls and 21 asthmatic adolescents gave blood samples three times over a semester: midsemester, during the week of final examinations, and 2-3 weeks after examinations. Interferon-gamma (IFN-gamma), IL-2, IL-4, and IL-5 were measured from supernatants of cells stimulated with PHA/PMA for 24 h. Cells from asthmatic subjects released significantly more IL-5 during the examination and postexamination periods, whereas cells from healthy controls released significantly more IL-2 during the midsemester and examination periods, thereby indicating a bias for a Th2-like pattern in asthmatics and a Th1-like pattern in healthy controls. IL-4 and IL-5 production showed a marked decrease during and after examinations in healthy controls, whereas this decline was absent in asthmatics. The ratios of IFN-gamma:IL-4 and IFN-gamma:IL-5 also revealed significant changes in the profile of cytokine release across the semester. These results indicate differential cytokine responses in asthmatics that may become pronounced during periods of cellular activation. 相似文献
3.
ME Sutherlin I Nishimori T Caffrey EP Bennett H Hassan U Mandel D Mack T Iwamura H Clausen MA Hollingsworth 《Canadian Metallurgical Quarterly》1997,57(21):4744-4748
The levels of mRNA expression of three UDP-N-acetyl-alpha-D-galactosamine:polypeptide GalNAc N-acetylgalactosaminyltransferases (GalNAc-transferases) were quantified for human adenocarcinoma cell lines from pancreas, colon, stomach, and breast. Two of the GalNAc-transferases, GalNAc-T1 and GalNAc-T2, were expressed constitutively and at low levels in most or all cell lines examined. A third GalNAc-transferase, GalNAc-T3, was differentially expressed. Well-differentiated adenocarcinoma cell lines expressed high levels and moderately differentiated cell lines expressed lower levels of GalNAc-T3. Cell lines classified as poorly differentiated failed to express GalNAc-T3 mRNA at levels that could be detected by Northern blot analysis. Differential expression of the GalNAc-T3 protein was confirmed in these cell lines by Western blotting. We propose that glycosylation in tumor cell lines may be regulated in part by differential expression of GalNAc-transferases, and we suggest that GalNAc-T3 gene expression may be a molecular indicator of differentiated adenocarcinoma. 相似文献
4.
CL Mesh BL Cmolik DW Van Heekeren JH Lee D Whittlesey LM Graham AS Geha SJ Bowlin 《Canadian Metallurgical Quarterly》1997,11(6):612-619
A premise of cardiac risk stratification is that the added risk of coronary artery bypass grafting (CABG) is offset by the improved safety of subsequent vascular reconstruction (VR). We questioned if elective CABG is patients with severe peripheral vascular disease (PVD) is a relatively high-risk procedure. A cohort study of 680 elective CABG patients from January 1993 to December 1994 was performed using three mutually exclusive outcomes of complication-free survival, morbidity, and mortality. Patient characteristic, operative, and outcome data were prospectively collected. Retrospective review determined that 58 patients had either a standard indication for or a history of VR. Overall CABG mortality was 2.5%, with statistically similar but relatively higher rates for PVD as compared to non-PVD patients. In contrast, major morbidity occurred at rates 3.6-fold higher in PVD patients (39.7%) than in disease-free patients (16.7%) after adjustment for the effects of patient and operative variables (odds ratio [OR] 3.67, 95% confidence interval [CI] 1.93-6.99). CABG morbidity in the PVD patient was most likely in those patients with aortoiliac (OR 9.51, CI 3.20-28.27) and aortic aneurysmal (OR 5.24, CI 1.28-21.41) disease types. CABG in PVD patients is associated with significant major morbidity. Such morbidity may preclude or alter the timing of subsequent VR. 相似文献
5.
S Mahanty CL King V Kumaraswami J Regunathan A Maya K Jayaraman JS Abrams EA Ottesen TB Nutman 《Canadian Metallurgical Quarterly》1993,151(7):3704-3711
Helminth infections in humans and animals are associated with strong T helper 2 (Th2) responses. To determine whether parasite-derived Ag preferentially expand a Th2-like cell population, a filter immunoplaque assay was used to enumerate the frequencies (F0) of PBMC and CD4(+)-enriched PBMC from individuals with helminth infections secreting selected cytokines in response to parasite-derived (PAg) and nonparasite antigens (NPAg). In 20 individuals with lymphatic filariasis, frequency analysis of PBMC secreting IL-4 and IFN-gamma indicated that the F0 of PAg-specific IL-4-secreting cells (geometric mean F0 (GM): 1/12,100) was 57-fold higher than the corresponding F0 of NPAg-reactive cells (GM: 1/692,000; p < 0.02). In marked contrast, the F0 of IFN-gamma-secreting cells responding to PAg (GM: 1/2,700) did not differ from those of cells specific for NAPg (GM: 1/3,400; p = 0.83). In another group of helminth-infected individuals, the F0 of highly enriched CD4+ cells secreting IL-4 and IL-5 in response to PAg (GMs: 1/2,600 and 1/5,600 CD4+ cells, respectively) were also found to be significantly higher than those specific for NPAg (GMs: 1/291,000 and 1/303,000 CD4+; p < 0.05 and p < 0.01, respectively), whereas the corresponding F0 of IFN-gamma- and granulocyte-macrophage-CSF-secreting cells were equivalent for PAg and NPag. Furthermore, the proportion of PAg-specific IL-4- and IL-5-secreting CD4+ cells relative to all cells secreting the given cytokine were approximately 29-fold higher than the proportion of NPAg-specific cells secreting these cytokines. Again, the corresponding proportions of Ag-specific IFN-gamma-and GM-CSF-secreting CD4+ cells were equivalent for PAg and NPAg. Thus, in this ex vivo system, a circulating population of IL-4- and IL-5-secreting (Th2-like) cells has been shown to exist in humans; PAg appears to expand these cells preferentially. 相似文献
6.
BB Horswell CL Castiglione AE Poole LA Assael 《Canadian Metallurgical Quarterly》1993,51(2):145-9; discussion 149-50
The double-reversing Z-plasty of Furlow for closure of the soft palate was used in 34 children with various types of cleft palate. Mean age at repair was 12.8 months. Intraoperative experience was favorable, with acceptable operating time and blood loss. Length of hospitalization averaged 1.9 days. Postoperatively, two children experienced temporary stridor, which resolved within 24 to 48 hours. One child had dehiscence of the hard palate (Von Lagenbeck repair) 4 weeks postoperatively, and three children developed small oronasal fistulae. Early speech evaluation demonstrated adequate soft palate mobility in 33 of 34 patients, with observable velopharyngeal function. Twelve children had mild velar compromise, with eight exhibiting slight nasal air escape. 相似文献
7.
8.
Three sporulation-specific genes (orfA, sigE, sigG) from clostridium acetobutylicum ATCC 824 are arranged in a cluster, encoding the putative sigma E-processing enzyme, sigma E, and sigma sigma G respectively. When they were transformed into Clostridium acetobutylicum while on a plasmid functional in this organism, transformants did not survive. Three kinds of recombinations were then attempted with nonreplicative plasmids: duplication of orfA and sigE, replacement of all of the three genes, and inactivation of orfA. While the wild-type strain ceased to grow and produce solvents in batch cultures after approximately 24 h, mutant strains were isolated that showed sustained growth for a much longer time and produced a threefold increase in acetone and butanol in test tube cultures. In addition, one of the derived strains showed a significantly higher growth rate. Features of the restriction maps of the recombinants did not correlate with expected maps, indicating possible complications occurring during the recombination events. 相似文献
9.
Occupational airway diseases are now receiving attention in industry, although study is hampered by a lack of readily-available data. The interpretation of the data that is available, and also of the root problems themselves, is itself a difficult problem. This paper has been written as a literature review which it is hoped that other researchers can take either as a starting point or as a refresher. 相似文献
10.
Larry Bennett 《Journal of Urban Affairs》1987,9(3):263-276
ABSTRACT: In 1983 Chicago elected its first black mayor, Harold Washington. During Washington's first term of office, his administration not only reordered municipal priorities in such a fashion as to benefit his core, minority voting constituency, but also defined a municipal agenda emphasizing greater attention to neighborhood needs and more open government. In 1984 an important neighborhood coalition, the Save Our Neighborhoods/Save Our City Coalition (SON/SOC), proposed a linked development policy to tap downtown investment for neighborhood projects. Although SON/SOC's proposal was compatible with the Washington neighborhood agenda, this mainly white organization and the Washington administration experienced considerable difficulty in forging a mutually acceptable proposal The linked development debate in Chicago demonstrates the salience of race, class-cultural factors, and alternative approaches to neighborhood mobilization as barriers to the development of progressive coalitions in city politics. 相似文献