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81.
Lina Jaurigue Elizabeth Robertson Janik Wolters Kathy Lüdge 《Entropy (Basel, Switzerland)》2021,23(12)
Reservoir computing is a machine learning method that solves tasks using the response of a dynamical system to a certain input. As the training scheme only involves optimising the weights of the responses of the dynamical system, this method is particularly suited for hardware implementation. Furthermore, the inherent memory of dynamical systems which are suitable for use as reservoirs mean that this method has the potential to perform well on time series prediction tasks, as well as other tasks with time dependence. However, reservoir computing still requires extensive task-dependent parameter optimisation in order to achieve good performance. We demonstrate that by including a time-delayed version of the input for various time series prediction tasks, good performance can be achieved with an unoptimised reservoir. Furthermore, we show that by including the appropriate time-delayed input, one unaltered reservoir can perform well on six different time series prediction tasks at a very low computational expense. Our approach is of particular relevance to hardware implemented reservoirs, as one does not necessarily have access to pertinent optimisation parameters in physical systems but the inclusion of an additional input is generally possible. 相似文献
82.
83.
Summary.
For univariate functions the Kronecker theorem, stating the equivalence
between the existence of an infinite block in the table of Padé approximants
and the approximated function being rational, is well-known.
In [Lubi88] Lubinsky proved that if is not rational, then its Padé table
is normal almost everywhere: for an at most countable set of points the
Taylor series expansion of is such that it generates a non-normal
Padé table. This implies that the Padé operator is an almost always
continuous operator because it is continuous when computing a normal
Padé approximant [Wuyt81].
In this paper we generalize the above results to the case of multivariate
Padé approximation. We distinguish between two different approaches for
the definition of multivariate Padé approximants: the general order one
introduced in [Levi76, CuVe84] and the so-called homogeneous one discussed
in [Cuyt84].
Received December 19, 1994 相似文献
84.
We show that whole mount preparations of embryonic chick sterna can be analyzed with confocal laser scanning microscopy (CLSM). This technique replaces the traditional sectioning of cartilage or culturing of chondrocytes. Whole ‘chunks’ of cartilage can be stained with dyes, used for immunohistochemistry or in situ hybridization. Although other stains have been used, the stains presented include phalloidin and propidium iodide which stain filamentous actin (F-actin) and the DNA and RNA of cells, respectively. Collagen secreting endoplasmic reticulum (ER) was localized with a primary antibody to chick prolyl hydroxylase (CPH) that was detected with a secondary antibody conjugated to FITC. The intracellular localization of type II collagen mRNA was analyzed using in situ hybridization. The cDNA probe specific for the C-propeptide region of the 1 type (II) collagen mRNA was nick translated and labeled with biotin-16-dUTP. Biotin labeled probes were visualized with avidin-FITC. Depending on the intensity of the stain, we were able to analyze approximately 3–10 layers of chondrocytes. Stains penetrated into the cartilage better than antibodies and biotin-avidin labeled cDNA probes. The F-actin was located as bands of filaments in the superficial layers of the cartilage and was associated with the membranes that marked cell boundaries as deep as 10 layers of chondrocytes. The ER stained with anti-chick prolyl hydroxylase was prominent in perinuclear regions of the cells, but the antibody was only able to penetrate 4–5 cell layers. Single label in situ hybridization studies show that chondrocytes are positive for type II collagen mRNA. Similar to the immunohistochemistry, in situ hybridization probes were only able to penetrate 4–5 cell layers. The type II collagen mRNA appeared perinuclear in the chondrocytes, similar to the ER staining pattern. 相似文献
85.
86.
We prove results for the interlacing of zeros of Jacobi polynomials of the same or adjacent degree as one or both of the parameters are shifted continuously within a certain range. Numerical examples are given to illustrate situations where interlacing fails to occur. 相似文献
87.
88.
Background
C57BL/6 mice show a relationship during aging between NMDA receptor expression and spatial reference memory performance in a 12-day task. The present study was designed to determine if age-related deficits could be detected with a shorter testing protocol and whether these deficits showed a relationship with NMDA receptors. Mice were trained in a reference memory task for two days in a Morris water maze. Cued testing was performed either after or prior to reference memory testing. Crude synaptosomes were prepared from prefrontal/frontal cortex and hippocampus of the mice that underwent reference memory testing first. NMDA receptor subunit and syntaxin proteins were analyzed with Western blotting. 相似文献89.
Lipid-lowering effects of ethyl 2-phenacyl-3-aryl-1H-pyrrole- 4-carboxylates in rodents 总被引:3,自引:0,他引:3
Holub JM O'Toole-Colin K Getzel A Argenti A Evans MA Smith DC Dalglish GA Rifat S Wilson DL Taylor BM Miott U Glersaye J Lam KS McCranor BJ Berkowitz JD Miller RB Lukens JR Krumpe K Gupton JT Burnham BS 《Molecules (Basel, Switzerland)》2004,9(3):134-157
A series of substituted 2-phenacyl-3-phenyl-1H-pyrrole-4-carboxylates were prepared from substituted acetophenones in 6 steps. The final condensations between a chloroenal and an aminoketone were carried out under neutral conditions in parallel to yield the series listed below. Selected pyrrole derivatives proved to be potent hypolipidemic agents lowering serum triglyceride concentrations in CF-1 male mice after 14 days of I.P. administration. One agent orally lowered serum cholesterol in Sprague-Dawley male rats at 2mg/kg/day after 14 days. The agents demonstrated a lowering of mouse serum LDL- cholesterol levels and selected compounds showed an elevation of serum HDL-cholesterol levels. The cholesterol concentrations in the liver were raised while the cholesterol and triglyceride contents of the aorta were significantly lowered by the selected trisubstituted pyrrole. 相似文献
90.