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91.
A traumatic macular hole has never been seen immediately after the causal accident. We examined a case of macular hole within half an hour of the injury and photographed it within three hours. We comment on the genesis of traumatic macular edema. 相似文献
92.
Distinctions are drawn between three mean strain rates in extrusion: those averaged over the accumulated strain, the distance
travelled through the die, and the elapsed time. It is shown that when the strain rate varies, the mean strain rate based
on strain is always the greatest, and the mean strain rate based on time the smallest. Three further mean strain rates are
introduced, which are root mean power (RMP) values of the above strain rates. Conventional estimates of the extrusion pressure
for frictionless, homogeneous flow are based on rate insensitive analyses and lead to pressures proportional to the mean strain
rate based on time. When the rate sensitivity during flow is taken into account, the calculated pressure is shown to be a
function of the RMP strain rate based on accumulated strain, which is considerably greater than the mean strain rate based
on time. Experiments are described in which ice was extruded by the indirect process, leading to nearly frictionless, homogeneous
flow. Extrusion ratios of 4, 9, 25, 81, and 144 were used. In the first series of experiments, the ram velocity was adjusted
to give the samerate insensitive (i.e. time-based) mean strain rate for all the dies. In the second series of experiments, the ram velocity was adjusted to give
the samerate sensitive (i.e. RMP) mean strain rate for all the dies. In all cases the extrusion pressure was proportional to the RMP strain rate and not
to the time-based strain rate. The rate sensitivity correction factor is also described. 相似文献
93.
Electrically quantitated and controlled detrusor contraction can produce either minimal or excessive rise in intravesical pressure depending upon openness or occlusion of the bladder outlet. Higher rise in intravesical pressure thus does not imply stronger detrusor contraction but should be viewed as a reflection of the outflow resistance mechanism. Possible damaging hydrodynamic effect of sudden partial or complete functional occlusion of the bladder outlet by intermittent or sustained voluntary sphincter activity is illustrated. 相似文献
94.
Mataev SI Sukhoveĭ IuG Petrov SA Popov AV Unger IG Vasil'kova TN Argunova GA 《Voprosy pitaniia》2004,73(3):25-30
The decrease of calorie in ration content, insufficient consumption of proteins and lipids was found among the patients in the condition of penitentiary establishment, it results in decrease of characteristics of natural immunity and resistibility to various infections agents, to the action of toxic substances, stress and other negative conditions that take place in penitentiary establishment a disbalanse of regulatory subpopulation of cellular consistent of immunity and predominance of suppressive-cytotoxic influence was observed among the patients of the penitentiary establishment (with a reduced ration of nutrition) over halt a year. Considering a health problem, in the establishments of imprisonment one may probably state that a reduced ration of nutrition is one of the main courses of immune homeostasis shift leasing in the basis of specific and non-specific phenomena of morbidity. 相似文献
95.
We have developed a novel strategy to identify enzyme inhibitors that interact directly with their enzyme targets. In the approach, an enzyme is immobilized on a sensor chip, and it is determined whether the immobilized enzyme is still active by incubation with model substrates and mass spectrometric analysis of the products. Putative inhibitors or mixtures containing putative inhibitors are then injected over the sensor chip for binding analysis with surface plasmon resonance. It is then tested whether the bound compounds inhibit the enzymatic activity by subsequent incubation with the model substrate and mass spectrometric analysis. If the bound compound inhibits the enzyme, the inhibitor is eluted from the enzyme and characterized by mass spectrometry. To test the strategy, it has been applied to the well-characterized interaction between trypsin and pure bovine pancreas trypsin inhibitor. Furthermore, fractions of plant extracts were screened for binding to and inhibition of carboxypeptidase B. 相似文献
96.
Nonpolar lipids and sound velocity at different distances from the skin surface within a sample of pilot whale melon were
studied. Thin layer chromatography, sensitive radioisotopic methods, and an ultrasonic echo scanner were used. Wax esters
had a maximum concentration at 11–12 cm from the skin surface. Non- and monoisovalero triglycerides both exhibited a minimum
at 8–10 cm, whereas the diisovalero species increased steadily from the skin surface towards the center of the pilot whale
head. A minimum of sound velocity, ca. 1340 m/s, was found at 9–11 cm, thus coinciding with a region rich in isovaleric acid
esterified in wax and diisovalero triglycerides. These findings are compatible with predictions based on the known correlations
between lipid structure and sound velocity. Consequently, additional evidence for refraction of sound in pilot whale melon
is presented. This is important in understanding the system of echolocation of toothed whales. 相似文献
97.
R. Müller M. Schneider C. Janowitz R.-St. Unger T. Stemmler A. Krapf H. Dwelk R. Manzke K. Roßnagel L. Kipp M. Skibowski 《Journal of Superconductivity》2001,14(6):659-668
A first Fermi surface map of a single-layer high-T
c superconductor is presented. The experiments were carried out on optimally doped Bi2Sr2 – xLaxCuO6 + (x = 0.40) with synchrotron radiation which allow to discuss in detail the strong polarization dependence of the emissions near the Fermi edge. For the cuprates, only little is known about the impact of the electron–photon matrix element determining the photoelectron intensity. For the example of the model layered superconductor Bi2Sr2 – xLaxCuO6 + , it will be demonstrated that the polarization geometry has significant influence on the energy distribution curves at E
F, and consequently also for the determination of the topology and character of the Fermi surface (FS) by angle-resolved photoemission. For further clarification also, a FS map of the n = 2 material Bi-2212 has been measured applying a different polarization geometry as previously used by Saini et al. In the context of the current debate on the character of the FS of Bi-cuprates, our results confirm a hole-like FS for n = 1 as well as for n = 2 material, what might be the universal FS for high-T
c superconductors. 相似文献
98.
Anselmo Antunes Montenegro Luiz Velho Paulo C. P. Carvalho Jonas Sossai Jr. 《Journal of Mathematical Imaging and Vision》2007,29(2-3):119-130
In this work we propose a method for computing mesh representations of 3D objects reconstructed from a set of silhouette images.
Our method is based on the polygonization of volumetric reconstructions by using a modified version of the dual contouring method. In order to apply dual contouring on volumetric reconstruction from silhouettes we devised a method that is able
to determine the discrete topology of the surface in relation to the octree cells. We also developed a new scheme for computing
hermitian data representing the intersections of conic volumes with the octree cells and their corresponding normals with
subpixel accuracy. Due to the discrete and extremely noisy nature of the data used in the reconstruction we had to devise
a different criterion for mesh simplification that applies topological consistency tests only when the geometric error measure
is beyond a given tolerance. We present results of the application of the proposed method in the extraction of a mesh corresponding
to the surface of objects of a real scene. 相似文献
99.
Frese Michael; Krauss Stefanie I.; Keith Nina; Escher Susanne; Grabarkiewicz Rafal; Luneng Siv Tonje; Heers Constanze; Unger Jens; Friedrich Christian 《Canadian Metallurgical Quarterly》2007,92(6):1481
A model of business success was developed with motivational resources (locus of control, self-efficacy, achievement motivation, and self-reported personal initiative) and cognitive resources (cognitive ability and human capital) as independent variables, business owners' elaborate and proactive planning as a mediator, and business size and growth as dependent variables. Three studies with a total of 408 African micro and small-scale business owners were conducted in South Africa, Zimbabwe, and Namibia. Structural equation analyses partially supported the hypotheses on the importance of psychological planning by the business owners. Elaborate and proactive planning was substantially related to business size and to an external evaluation of business success and was a (partial) mediator for the relationship between cognitive resources and business success. The model carries important implications for selection, training, and coaching of business owners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Two-tier streaming settings are a typical dynamic environment where continuous skylines represent an important semantic indicator for multiple attributes. To monitor skylines over the dynamic data in such settings, one needs to continuously update the skyline query results in order to reflect the new data values. This paper tackles the problem of continuous skyline monitoring on a central query server over dynamic data from multiple data sites. Simply sending the updates of tuple values to the server is cost-prohibitive. Therefore, we propose an approach that allows the central server to collaborate with the data sites to monitor the possible skyline changes. By doing so, the processing load is distributed over all the data sites instead of only on the central server. Furthermore, this collaborative approach minimizes the bandwidth consumption between the server and the data sites, which is often critical in a widely distributed environment such as a wide-area sensor network. We give theoretical upper bounds for the computation costs and communication costs of the proposed collaborative approach. We also conduct extensive experiments on both synthetic and real data sets. The experimental results demonstrate that our collaborative approach is efficient, scalable and well-balanced in terms of communication costs and computation costs. 相似文献