991 resultados para beta regression
Resumo:
A 30 kDa beta-galactose-specific lectin named CVL was isolated from the polychaete marine worm Chaetopterus variopedatus (Annelida) and its anti-HIV-1 activity in vitro was determined. Results showed that CVL inhibited cytopathic effect induced by HIV-1 a
Resumo:
A variety of N-acetyl-o-aryl-1,2-didehydroethylamines were synthesized by direct reduction-acetylation of beta-aryl-nitroolefins and assayed as HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs) for the first time. Compound 7a exhibited a TI v
Resumo:
A beta-carboline compound, flazin isolated from Suillus granulatus has been shown weak anti-HIV-1 activity. Based on the structure of flazin, flazinamide [1-(5'-hydromethyl-2'-furyl)-beta-carboline-3-carboxamide] was synthesized and its anti-HIV activitie
Resumo:
The role of the collagen-platelet interaction is of crucial importance to the haemostatic response during both injury and pathogenesis of the blood vessel wall. Of particular interest is the high affinity interaction of the platelet transmembrane receptor, alpha 2 beta 1, responsible for firm attachment of platelets to collagen at and around injury sites. We employ single molecule force spectroscopy (SMFS) using the atomic force microscope (AFM) to study the interaction of the I-domain from integrin alpha 2 beta 1 with a synthetic collagen related triple-helical peptide containing the high-affinity integrin-binding GFOGER motif, and a control peptide lacking this sequence, referred to as GPP. By utilising synthetic peptides in this manner we are able to study at the molecular level subtleties that would otherwise be lost when considering cell-to-collagen matrix interactions using ensemble techniques. We demonstrate for the first time the complexity of this interaction as illustrated by the complex multi-peaked force spectra and confirm specificity using control blocking experiments. In addition we observe specific interaction of the GPP peptide sequence with the I-domain. We propose a model to explain these observations.
Resumo:
Despite its importance, choosing the structural form of the kernel in nonparametric regression remains a black art. We define a space of kernel structures which are built compositionally by adding and multiplying a small number of base kernels. We present a method for searching over this space of structures which mirrors the scientific discovery process. The learned structures can often decompose functions into interpretable components and enable long-range extrapolation on time-series datasets. Our structure search method outperforms many widely used kernels and kernel combination methods on a variety of prediction tasks.
Resumo:
We develop a convex relaxation of maximum a posteriori estimation of a mixture of regression models. Although our relaxation involves a semidefinite matrix variable, we reformulate the problem to eliminate the need for general semidefinite programming. In particular, we provide two reformulations that admit fast algorithms. The first is a max-min spectral reformulation exploiting quasi-Newton descent. The second is a min-min reformulation consisting of fast alternating steps of closed-form updates. We evaluate the methods against Expectation-Maximization in a real problem of motion segmentation from video data.