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991.
We give an overview of current methods for the detection of point mutations as well as small insertions and deletions in clinical diagnostics. For each method, the following characteristics are specified: (a) principle, (b) major modifications, (c) maximum fragment size that can be analyzed, (d) ratio and type of mutations that can be detected (e) minimum ratio of mutant to wild-type alleles at which mutations can be detected, and (j) detection methods. Special attention is paid to the possibilities of quality assessment and the potential for standardization and automation.  相似文献   
992.
993.
Preparation of Papers   总被引:8,自引:0,他引:8  
We motivate the study of a vector variational inequality by a practical flow equilibrium problem on a network, namely a generalization of the well-known Wardrop equilibrium principle. Both weak and strong forms of the vector variational inequality are discussed and their relationships to a vector optimization problem are established under various convexity assumptions.  相似文献   
994.
We classify smooth subvarieties of codimension twoXP n , 4≤n≤5, which are arithmetically Cohen-Macaulay and of non general type. By the way we exhibit some classes of non extendable subvarieties. Then we give new proofs of the classification of scrolls inP 4; finally we consider smooth surfaces of non general type inP 4 arising from rank three vector bundles.
Sunto Classifichiamo le sottovarietà lisce di codimensione dueXP n , 4≤n≤5, aritmeticamente Cohen-Macaulay e non di tipo generale. Nel contempo descriviamo alcune classi di sottovarietà non estendibili. Diamo poi due nuove dimostrazioni della classificazione degli scrolls inP 4; infine consideriamo superfici lisce inP 4, non di tipo generale, associate a fibrati di rango tre.
  相似文献   
995.
LetB1: n× N1m1,B2: n× N2m2andQ: m2m1be bilinear forms which are related as follows: ifμandνsatisfyB1(ξ, μ)=0 andB2(ξ, ν)=0 for someξ≠0, thenμτ=0. Supposep−1+q−1=1. Coifman, Lions, Meyer and Semmes proved that, ifuLp( n) andvLq( n), and the first order systemsB1(D, u)=0,B2(D, v)=0 hold, thenuτQvbelongs to the Hardy spaceH1( n), provided that both (i)p=q=2, and (ii) the ranks of the linear mapsBj(ξ, ·) : Njm1are constant. We apply the theory of paracommutators to show that this result remains valid when only one of the hypotheses (i), (ii) is postulated. The removal of the constant-rank condition whenp=q=2 involves the use of a deep result of Lojasiewicz from singularity theory.  相似文献   
996.
997.
The constrained optimization problem with a quadratic cost functional and two quadratic equality constraints has been studied by Bar-on and Grasse, with positive-definite matrix in the objective. In this note, we shall relax the matrix in the objective to be positive semidefinite. A necessary and sufficient condition to characterize a local optimal solution to be global is established. Also, a perturbation scheme is proposed to solve this generalized problem.  相似文献   
998.
Summary Th(IV) was quantitatively extracted from 1 . 10-3M HNO3 using 1 . 10-3M Cyanex302 in xylene and was stripped from the organic phase with 5M HCl. The effect of different parameters affecting the extraction was systematically studied to achieve optimum conditions for the extraction of thorium. Based on the data some separations of thorium from binary and complex mixtures and its recovery from monazite sand were achieved. The method is reproducible with a relative standard deviation of 0.4%.  相似文献   
999.
Complete and incomplete fusion cross sections for the 9Be + 144Sm reaction have been measured at near-barrier energies, using the delayed X-ray detection technique. At above-barrier energies these show a suppression of complete fusion for this weakly bound projectile on an intermediate mass target. The suppression factor, attributed to 9Be break-up, was deduced from a comparison of complete fusion yields with coupled-channels calculations, and appears consistent with measured incomplete fusion product yields. At ∼10%, it is considerably smaller than the value of ∼30% previously found for a 208Pb target. Simultaneous measurements of elastic and inelastic scattering permit a clearer picture of the reaction mechanisms.  相似文献   
1000.
We study the spectrum and eigenmodes of the QCD Dirac operator in a gauge background given by an instanton liquid model (ILM) at temperatures around the chiral phase transition. Generically we find the Dirac eigenvectors become more localized as the temperature is increased. At the chiral phase transition, both the low lying eigenmodes and the spectrum of the QCD Dirac operator undergo a transition to localization similar to the one observed in a disordered conductor. This suggests that Anderson localization is the fundamental mechanism driving the chiral phase transition. We also find an additional temperature dependent mobility edge (separating delocalized from localized eigenstates) in the bulk of the spectrum which moves toward lower eigenvalues as the temperature is increased. In both regions, the origin and the bulk, the transition to localization exhibits features of a 3D Anderson transition including multifractal eigenstates and spectral properties that are well described by critical statistics. Similar results are obtained in both the quenched and the unquenched case though the critical temperature in the unquenched case is lower. Finally we argue that our findings are not in principle restricted to the ILM approximation and may also be found in lattice simulations.  相似文献   
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