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排序方式: 共有159条查询结果,搜索用时 78 毫秒
11.
J.?Bartels M.?Braun G.?P.?VaccaEmail author 《The European Physical Journal C - Particles and Fields》2005,40(3):419-433
We analyze the momentum space triple pomeron vertex in perturbative QCD. In addition to the standard form of this vertex which is used in the context of total cross sections at high energies and in the QCD reggeon field theory, there exists an alternative form which has to be used in the study of high-mass diffraction. We review and analyze the relation between these two versions. We discuss some implications for the BK equation. In the second part of our paper we extend this analysis to the pomeron-odderon-odderon vertex.Received: 11 January 2005, Revised: 24 January 2005, Published online: 3 March 2005 相似文献
12.
Oliveira JS Sousa EH Basso LA Palaci M Dietze R Santos DS Moreira IS 《Chemical communications (Cambridge, England)》2004,(3):312-313
The in vitro kinetics of inactivation of both wild-type and I21V InhA enzymes by [FeII(CN)5(INH)]3- indicate that this process requires no activation by KatG, and no need for the presence of NADH. This inorganic complex may represent a new class of lead compounds to the development of anti-tubercular agents aiming at inhibition of a validated target. 相似文献
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Jannik Matuschke S. Thomas McCormick Gianpaolo Oriolo Britta Peis Martin Skutella 《Operations Research Letters》2017,45(1):53-59
We present a new robust optimization model for the problem of maximizing the amount of flow surviving the attack of an interdictor. Given some path flow, our model allows the interdictor to specify the amount of flow removed from each path individually. In contrast to previous models, for which no efficient algorithms are known, the most important basic variants of our model can be solved in poly-time. We also consider extensions where there is a budget to set the interdiction costs. 相似文献
17.
A spectrophotometric flow injection procedure involving N,N-dimethyl-p-phenylenediamine (DMPD) is applied to the sulfide monitoring of a sugar fermentation by Saccharomyces cerevisiae under laboratory conditions. The gaseous chemical species evolving from the fermentative process, mainly CO2, are trapped allowing a cleaned sample aliquot to be collected and introduced into the flow injection analyzer. Measurement rate, signal repeatability, detection limit and reagent consumption per measurement were estimated as 150 h−1, 0.36% (n = 20), 0.014 mg L−1 S and 120 μg DMPD, respectively. The main characteristics of the monitoring record are discussed. The strategy is worthwhile for selecting yeast strain, increasing the industrial ethanol production and improving the quality of wines. 相似文献
18.
Sperb F Werlang IC Margis-Pinheiro M Basso LA Santos DS Pasquali G 《Applied biochemistry and biotechnology》2011,165(2):652-665
Erythropoietin (EPO) is a hormone belonging to a group of hematopoietic growth factors that control the proliferation and
differentiation of bone marrow cells. It induces the production of erythrocytes, thereby increasing the amount of circulating
hemoglobin and oxygen. Previous attempts to transgenically express human EPO in plants failed to succeed because the plants
exhibited abnormal morphology and infertility. In the present work, we describe the generation of fertile transgenic tobacco
plants able to express a synthetic version of human EPO. A 582-bp fragment of the human EPO gene was synthesized using a PCR-based
method and ligated into pCR-Blunt. After sequencing, the human EPO fragment was transferred to pWUbi.tm1 and the expression
cassette was then transferred to the binary vector pWBVec4a. After Agrobacterium-mediated transformation of Nicotiana tabacum SR1 plants, integration of the transgene into T0 and T1 plant genomes was confirmed by PCR. The human EPO gene was found to be expressed in tobacco leaves at the mRNA and protein
levels. Self-crossing allowed us to obtain T1 plants exhibiting Mendelian segregation of the transgene. None of the plants presented any kind of malformation or deformity. 相似文献
19.
De Moliner F Banfi L Riva R Basso A 《Combinatorial chemistry & high throughput screening》2011,14(9):782-810
The reaction of isocyanides with electron deficient alkynes has been first reported in 1969, about ten years after the first reports on the famous Ugi four component reaction. However it took about thirty years to realise that the zwitterionic intermediate originating from interaction of the two species could be trapped by a third component, thus giving the start to a novel class of isocyanide-based multicomponent reactions. From that first report dated 1996 there has been an ongrowing interest that has produced, so far, about 150 distinct scientific papers. This review is aimed at rationalising and cathegorising these reports and at offering an overview of all the possible applications of this novel methodology. 相似文献
20.
Alessandra Basso Sabine L. Flitsch Ian Brazendale Paolo Linda Lucia Gardossi 《Tetrahedron》2005,61(4):971-976
Hydrolytic yields as high as 80% were obtained by using penicillin G amidase (PGA) on substrates anchored on optimized positively charged PEGA polymers. By increasing the amount of permanent charges inside the polymer, electrostatic interactions between the positively charged PEGA+ and the negatively charged PGA (pI=5.2-5.4) were strengthened, thus favouring the accessibility of the bulky enzyme (MW=88 kDa) inside the pores. The effect of different amounts of charges on polymer swelling and protein retention inside the polymer was investigated and correlated to the enzyme efficiency demonstrating that electrostatic interactions predominate over swelling properties in determining enzyme accessibility. 相似文献