981 resultados para QSAR-2D


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L’objectiu del projecte és la creació d’un motor gràfic id’esdeveniments per a jocs RPG per a plataformes mòbils, en aquest casper a Nintendo DS. S’ha de remarcar que el que s’està proposant no és laprogramació d’un videojoc, sinó que el que es desenvoluparà és el motorde joc. Aquest motor comptarà no solament amb la funcionalitat bàsica devisualització i animació d’escenaris i personatges, detecció de col•lisionsentre personatges i elements de l’escenari, sinó que a més, comptarà ambles funcionalitats pròpies dels jocs més sofisticats (esdeveniments). Aquestmotor és compatible per a Nintendo DS i/o qualsevol emulador d’aquestaplataforma per a PC

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The Cognitive Reflection Test (CRT) is a test introduced by S. Frederick (2005) Cognitive reflection and decision making, J Econ Perspect 19(4): 25-42. The task is designed to measure the tendency to override an intuitive response that is incorrect and to engage in further reflection that leads to the correct response. The consistent sex differences in CRT performance may suggest a role for gonadal hormones, particularly testosterone. A now widely studied putative marker for fetal testosterone is the second-to-fourth digit ratio (2D:4D). This paper tests to what extent 2D:4D, as a proxy for prenatal exposure to testosterone, can predict CRT scores in a sample of 623 students. After controlling for sex, we observe that a lower 2D:4D (reflecting a higher exposure to testosterone) is significantly associated with a higher number of correct answers. The result holds for both hands? 2D:4Ds. In addition, the effect appears to be sharper for females than for males. We also control for patience and math proficiency, which are significantly related to performance in the CRT. But the effect of 2D:4D on performance in CRT is not reduced with these controls, implying that these variables are not mediating the relationship between digit ratio and CRT.

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The aim of the present study is to determine the level of correlation between the 3-dimensional (3D) characteristics of trabecular bone microarchitecture, as evaluated using microcomputed tomography (μCT) reconstruction, and trabecular bone score (TBS), as evaluated using 2D projection images directly derived from 3D μCT reconstruction (TBSμCT). Moreover, we have evaluated the effects of image degradation (resolution and noise) and X-ray energy of projection on these correlations. Thirty human cadaveric vertebrae were acquired on a microscanner at an isotropic resolution of 93μm. The 3D microarchitecture parameters were obtained using MicroView (GE Healthcare, Wauwatosa, MI). The 2D projections of these 3D models were generated using the Beer-Lambert law at different X-ray energies. Degradation of image resolution was simulated (from 93 to 1488μm). Relationships between 3D microarchitecture parameters and TBSμCT at different resolutions were evaluated using linear regression analysis. Significant correlations were observed between TBSμCT and 3D microarchitecture parameters, regardless of the resolution. Correlations were detected that were strongly to intermediately positive for connectivity density (0.711≤r(2)≤0.752) and trabecular number (0.584≤r(2)≤0.648) and negative for trabecular space (-0.407 ≤r(2)≤-0.491), up to a pixel size of 1023μm. In addition, TBSμCT values were strongly correlated between each other (0.77≤r(2)≤0.96). Study results show that the correlations between TBSμCT at 93μm and 3D microarchitecture parameters are weakly impacted by the degradation of image resolution and the presence of noise.

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El proyecto consistirá en diseñar desde cero un juego para smartphones que utilicen el sistema operativo Android. El objetivo del juego será sobrevivir a las oleadas de enemigos, que aparecerán en el extremo derecho de la pantalla y se dirigirán al lado opuesto, durante el tiempo suficiente para superar el nivel actual. Al mismo tiempo tendremos que tratar de esquivar los obstáculos y recoger los objetos que nos proporcionarán un bonus de puntos. En el juego habrá un número finito de niveles, cada uno más difícil que el anterior.

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Flood simulation studies use spatial-temporal rainfall data input into distributed hydrological models. A correct description of rainfall in space and in time contributes to improvements on hydrological modelling and design. This work is focused on the analysis of 2-D convective structures (rain cells), whose contribution is especially significant in most flood events. The objective of this paper is to provide statistical descriptors and distribution functions for convective structure characteristics of precipitation systems producing floods in Catalonia (NE Spain). To achieve this purpose heavy rainfall events recorded between 1996 and 2000 have been analysed. By means of weather radar, and applying 2-D radar algorithms a distinction between convective and stratiform precipitation is made. These data are introduced and analyzed with a GIS. In a first step different groups of connected pixels with convective precipitation are identified. Only convective structures with an area greater than 32 km2 are selected. Then, geometric characteristics (area, perimeter, orientation and dimensions of the ellipse), and rainfall statistics (maximum, mean, minimum, range, standard deviation, and sum) of these structures are obtained and stored in a database. Finally, descriptive statistics for selected characteristics are calculated and statistical distributions are fitted to the observed frequency distributions. Statistical analyses reveal that the Generalized Pareto distribution for the area and the Generalized Extreme Value distribution for the perimeter, dimensions, orientation and mean areal precipitation are the statistical distributions that best fit the observed ones of these parameters. The statistical descriptors and the probability distribution functions obtained are of direct use as an input in spatial rainfall generators.

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Abstract Objective: To compare the diagnostic performance of the three-dimensional turbo spin-echo (3D TSE) magnetic resonance imaging (MRI) technique with the performance of the standard two-dimensional turbo spin-echo (2D TSE) protocol at 1.5 T, in the detection of meniscal and ligament tears. Materials and Methods: Thirty-eight patients were imaged twice, first with a standard multiplanar 2D TSE MR technique, and then with a 3D TSE technique, both in the same 1.5 T MRI scanner. The patients underwent knee arthroscopy within the first three days after the MRI. Using arthroscopy as the reference standard, we determined the diagnostic performance and agreement. Results: For detecting anterior cruciate ligament tears, the 3D TSE and routine 2D TSE techniques showed similar values for sensitivity (93% and 93%, respectively) and specificity (80% and 85%, respectively). For detecting medial meniscal tears, the two techniques also had similar sensitivity (85% and 83%, respectively) and specificity (68% and 71%, respectively). In addition, for detecting lateral meniscal tears, the two techniques had similar sensitivity (58% and 54%, respectively) and specificity (82% and 92%, respectively). There was a substantial to almost perfect intraobserver and interobserver agreement when comparing the readings for both techniques. Conclusion: The 3D TSE technique has a diagnostic performance similar to that of the routine 2D TSE protocol for detecting meniscal and anterior cruciate ligament tears at 1.5 T, with the advantage of faster acquisition.

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QSAR studies based on flow microcalorimetric bioassay data for interaction of homologous series of m-alkoxyphenols and p-hydroxybenzoates with E. coli cells were carried out applying factorial design. Results for both series showed a linear relationship between log(dose)max and log Po/w. Analysis of these data allows the identification of contributions toward the derived bioactivity from the parent structures (the molecule minus n-CH2 groups present in the side-chain) and the lipophilic groups, CH2. These results are discussed with respect to drug quantitative structure-relationship.

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The synthesis and NMR analysis of seven new 4-(aryl)amino-5-carboethoxy-1,3-dimethyl-1H-pyrazolo[3,4- b]pyridines (7-13) are described. The synthetic approach used involved the preparation of intermediates 5-aminopyrazol (4), the enamine derivative (5) and the 4-chloro-1H-pyrazolo[3,4-b]pyridine (6). Compounds (7-13) were obtained by treatment of 6 with the desired aniline. The structures of new heterocyclic compounds and their precursors intermediates were assigned on the basis of spectral analysis including 1D and 2D NMR experiments [¹H; 13C{¹H} and DEPT; ¹H x ¹H - COSY; ¹H x13C - COSY, nJ CH, n = 1, 2 or 3 (HETECOR and COLOC)].

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A view of the general aspects involving the 2D NMR spectroscopy using inverse detection and field gradient techniques is presented through the analysis of a sesquiterpene.

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The comparative QSAR is a tool for validating any statistical model that seems to be reasonable in describing an interaction between a bioactive new chemical entity, BIONCE, and the biological system. In order to deeper the understanding of the relationships and the meaning of parameters within the model it is necessary some kind of lateral validation. This validation can be accomplished by chemical procedures using physicochemical organic reactions and by means of biological systems. In this paper we review some of such comparisons and also present a lateral validation between the same set of antimicrobial hydrazides acting against Saccharomyces cerevisiae yeast and Escherichia coli bacterium cells. QSARs are presented to shed light in this important way of stating that the QSAR model is not the endpoint, but the beginning.

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The process of building mathematical models in quantitative structure-activity relationship (QSAR) studies is generally limited by the size of the dataset used to select variables from. For huge datasets, the task of selecting a given number of variables that produces the best linear model can be enormous, if not unfeasible. In this case, some methods can be used to separate good parameter combinations from the bad ones. In this paper three methodologies are analyzed: systematic search, genetic algorithm and chemometric methods. These methods have been exposed and discussed through practical examples.

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A new model for the H2 antagonists binding site is postulated based on adsorption coefficient values of sixteen antagonists, in the affinities constants of the primary and secondary binding sites, and in the chemical characterization of these sites by 3D-QSAR. All study compounds are in the extended conformation and deprotonated form. The lateral validation of the QSARs, CoMFA analysis, affinity constants and chemical similarity data suggest that the antagonists block the proton pump in the H2 receptor interacting with two tyrosines - one in the helix 5, and other in the helix 6.