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121.
Abstract  In this paper we study smooth, non-special scrolls S of degree d, genus g ≥ 0, with general moduli. In particular, we study the scheme of unisecant curves of a given degree on S. Our approach is mostly based on degeneration techniques. Keywords Ruled surfaces, Hilbert schemes of scrolls, Moduli, Embedded degenerations Mathematics Subject Classification (2000) 14J26, 14D06, 14C20, (Secondary) 14H60, 14N10  相似文献   
122.
Intact protein masses from immortal, nontransformed MCF10A, a human breast epithelial cell line, and its malignant derivative MCF10CA1a.cl1 have been mapped using a combination of all-liquid separations and automated data interpretation. Preparative liquid isoelectric focusing combined with nonporous silica reverse-phase high-performance liquid chromatography allows efficient separation of a large number of proteins in complex mixtures such as whole-cell lysates. Molecular weight determination of these proteins is achieved using electrospray-time of flight-mass spectrometry, however, manual data analysis for these separations is both complex and time-consuming. Protein mass mapping can be significantly enhanced by automating deconvolution functions typically performed manually, with resulting reductions in hands-on analysis time from 20-30 h per chromatogram to approximately 15 min. This reduction in analysis time allows for rapid screening of cancer cell lines for potential biomarkers over a wider pI range than would otherwise be possible.  相似文献   
123.

Background  

Annexin A7 is a member of the annexin protein family, which is characterized by its ability to interact with phospholipids in the presence of Ca2+-ions and which is thought to function in Ca2+-homeostasis. Results from mutant mice showed altered Ca2+-wave propagation in astrocytes. As the appearance and distribution of Annexin A7 during brain development has not been investigated so far, we focused on the distribution of Annexin A7 protein during mouse embryogenesis in the developing central nervous system and in the adult mouse brain.  相似文献   
124.
We describe an innovative implementation of the Shack-Hartmann wave-front sensor that is designed to correct the perspective elongation of a laser guide beacon in adaptive optics. Subapertures are defined by the segments of a deformable mirror rather than by a conventional lenslet array. A bias tilt on each segment separates the beacon images on the sensor's detector. One removes the perspective elongation by dynamically driving each segment with a predetermined open-loop signal that would, in the absence of atmospheric wave-front aberration, keep the corresponding beacon image centered on the subaperture's optical axis.  相似文献   
125.
(Trialkylsilyl)vinylketenes react with lithium ynolates to produce highly substituted phenols in a new benzannulation strategy that proceeds via the 6pi electrocyclization of an intermediate 3-(oxido)dienylketene. [reaction: see text]  相似文献   
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127.
We give several classes of facets for the convex hull of incidence vectors of stable sets in a K1,3-free graph, including facets with (a, a + 1)-valued coefficients, where a = 1, 2, 3,…. These provide counterexamples to three recent conjectures concerning such facets. We also give a necessary and sufficient condition for a minimal imperfect graph to be an odd hole or an odd antihole and indicate that minimal imperfect K1,3-free graphs satisfy the condition.  相似文献   
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129.
Ohne Zusammenfassung
Comparative examinations on the determination of amylase activity
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130.
The present work investigated the temporal tuning of the auditory motion aftereffect (aMAE) by measuring the time course of adaptation and recovery to auditory motion exposure. On every trial, listeners were first exposed to a broadband, horizontally moving sound source for either 1 or 5 seconds, then presented moving test stimuli after delays of 0, 2/3, or 1 2/3 seconds. All stimuli were synthesized from head related transfer functions recorded for each participant. One second of motion exposure (i.e., a single pass of the moving source) produced clearly measurable aMAEs which generally decayed monotonically after adaptation ended, while five seconds exposure produced stronger aftereffects that remained largely unattenuated across test delays. These differences may imply two components to the aMAE: a short time-constant motion illusion and a longer time-constant response bias. Finally, aftereffects were produced only by adaptor movement toward but not away from listener midline. This aftereffect asymmetry may also be a consequence of brief adaptation times and reflect initial neural response to auditory motion in primate auditory cortex.  相似文献   
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