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1.
L Bini B Magi B Marzocchi F Arcuri S Tripodi M Cintorino JC Sanchez S Frutiger G Hughes V Pallini DF Hochstrasser P Tosi 《Canadian Metallurgical Quarterly》1997,18(15):2832-2841
Reference two-dimensional (2-D) gels are presented for human breast ductal carcinoma and histologically normal tissue. Whole biopsy fragments were analyzed, including epithelial and nonepithelial components. Thirty-five spots have been assigned by gel matching to the human liver SWISS-2DPAGE reference map and/or to the human primary keratinocyte IPG map from the Danish Center for Human Genome. N-terminal microsequencing was applied to confirm randomly chosen matching assignments and to identify six new spots. Protein expression profiles in ductal carcinoma and in normal breast tissue appeared to be similar, except for a pattern consisting of 32 spots, which were highly expressed in all carcinoma specimens, and less intense and occasionally undetectable in normal tissue. This difference was statistically significant. Assignment has been obtained for several spots, namely GRP94, GRP78, GRP75, mitochondrial HSP60, calreticulin, protein disulfide isomerase, peptidyl-prolyl cis-trans isomerase, collagen-binding protein 2, fructose bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, thioredoxin, cytochrome c oxidase VA subunit, tubulin beta isoform and macrophage migration inhibitory factor (MIF). The cancer- and tissue-specificity of the described pattern was assessed by matching to the Swiss-2DPAGE human liver, hepatoma, lymphoma, erythroleukemia reference maps. The pattern of 32 spots was found to be indicative of epithelial neoplasia. 相似文献
2.
It is well known that the performance of computer controlled systems is heavily affected by delays and jitter occurring in
the control loops, which are mainly caused by the interference introduced by other concurrent activities. A common approach
adopted to reduce delay and jitter in periodic task systems is to decrease relative deadlines as much as possible, but without
jeopardizing the schedulability of the task set.
In this paper, we formally characterize the region of admissible deadlines so that the system designer can appropriately select
the desired values to maximize a given performance index defined over the task set. Finally we also provide a sufficient region
of feasible deadlines which is proved to be convex.
相似文献
Giorgio ButtazzoEmail: |
3.
Summary We assessed the contribution of Brazilian limnologists (freshwater ecologists) in international journals in the period 1970-2004.
Brazilian contribution was low and regular in the 1970's, but increased steeply after 1980 with no signs of stabilization
until the present. Articles authored by Brazilians tend to be less cited than articles authored by non-Brazilians, although
this difference is reduced in co-authored articles with international researchers. Brazilian articles are not distributed
homogenously among the sub-areas of Limnology, but present some biases that can be explained by intellectual legacy. Brazil
has invested since the 1970's in establishing postgraduate courses in Brazil and in the last years has turned the focus to
a better qualification of these courses. We believe these are the main reasons for the conspicuous development of Brazilian
Limnology. 相似文献
4.
We present a practical modification of the recent divide-and-conquer algorithms of [3] for approximating the eigenvalues of a real symmetric tridiagonal matrix. In this modified version, we avoid the numerical stability problems of the algorithms of [3] but preserve their insensitivity to clustering the eigenvalues and the possibility to give a priori upper bounds on their computational cost for any input matrix. We confirm the theoretical effectiveness of our algorithms by numerical experiments. 相似文献
5.
S Guarini C Bazzani GM Ricigliano A Bini A Tomasi A Bertolini 《Canadian Metallurgical Quarterly》1996,119(1):29-34
The protein fusion technique was applied in the synthesis of an artificial dimer of ribonuclease H (305 residues). 1H NMR spectroscopy was used to analyze the structure of this dimer. Spectral profiles and pKa values of the histidine residues obtained using 1H NMR indicate that the dimer retains the secondary and tertiary structures of the intact monomer. Selective spin-lattice relaxation measurements suggest that the two monomeric units in the dimer are in tight contact. Furthermore, the 2D 1H NMR and paramagnetic relaxation filter results show that the two monomers bind together through interactions between the N- and C-terminal sites of the linked regions. 相似文献
6.
Polymerization processes are probably the most relevant example of a chemical reaction activated by catalysts or radical initiators. Among polymers, polyethylene is by far the most common and largely produced. Here we present a high-pressure synthesis of high-density crystalline polyethylene by using only physical tools such as pressure and light. Low-density polyethylene is obtained by compressing ethylene at room temperature above 3 GPa in the ordered crystal phase, and a highly crystalline polymer is produced in the fluid phase at pressures lower than 1 GPa by using continuous-wave laser lines (lambda < or = 460 nm) as an optical catalyst. The photo-activation is based on a two-photon absorption process to pi* antibonding states, where the change in molecular geometry favours the polymeric chain formation. The high yield and crystallinity of the polymer recovered by the photoinduced reaction and the simplicity of the synthesis make this process appealing for large-scale applications. 相似文献
8.
Sensitivity analysis for fixed-priority real-time systems 总被引:1,自引:1,他引:0
At early stages in the design of real-time embedded applications, the timing attributes of the computational activities are often incompletely specified or subject to changes. Later in the development cycle, schedulability analysis can be used to check the feasibility of the task set. However, the knowledge of the worst-case response times of tasks is often not sufficient to precisely determine the actions that would correct a non-schedulable design. In these situations, sensitivity analysis provides useful information for changing the implementation, by giving a measure of those computation times that must be reduced to achieve feasibility, or those that can be increased in case of a product extension, or providing the range of feasible periods for selecting the proper task activation rates. In this work, we exploit the concept of feasibility region to propose a faster and more concise solution to the sensitivity analysis problem with respect to existing techniques based on binary search. Furthermore, we show how the formalization of other problems in the feasibility domain, such as managing overloads through elastic scheduling, can be extended to the exact analysis. 相似文献
9.
André Andrian Padial João Carlos Nabout Tadeu Siqueira Luis Mauricio Bini José Alexandre Felizola Diniz-Filho 《Scientometrics》2010,85(1):1-12
Citation frequency has been considered a biased surrogate of publication merit. However, previous studies on this subject
were based on small sample sizes and were entirely based on null-hypothesis significance testing. Here we evaluated the relative
effects of different predictors on citation frequency of ecological articles using an information theory framework designed
to evaluate multiple competing hypotheses. Supposed predictors of citation frequency (e.g., number of authors, length of articles)
accounted for a low fraction of the total variation. We argue that biases concerning citation are minor in ecology and further
studies that attempt to quantify the scientific relevance of an article, aiming to make further relationships with citation,
are needed to advance our understanding of why an article is cited. 相似文献
10.
E. Serra A. Calza Bini G. Cosoli L. Pilloni 《Journal of the American Ceramic Society》2005,88(1):15-18
The aim of this work is to measure the hydrogen transport and solubility parameters in the commercial alumina. Measurements are conducted using a time-dependent permeation method over the temperature range 1273–1673 K with hydrogen driving pressures in the range 104 –105 Pa (100–1000 mbar). A half-power pressure dependence (diffusion-limited permeation) of the permeation flux for alumina is observed. The Arrhenius expressions for the hydrogen permeability, diffusivity, and Sieverts' constant values obtained from a fitting to the whole temperature range are as follows: