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71.
Longitudinal analysis of the role of perceived self-efficacy for self-regulated learning in academic continuance and achievement. 总被引:1,自引:0,他引:1
Caprara Gian Vittorio; Fida Roberta; Vecchione Michele; Del Bove Giannetta; Vecchio Giovanni Maria; Barbaranelli Claudio; Bandura Albert 《Canadian Metallurgical Quarterly》2008,100(3):525
The present study examined the developmental course of perceived efficacy for self-regulated learning and its contribution to academic achievement and likelihood of remaining in school in a sample of 412 Italian students (48% males and 52% females ranging in age from 12 to 22 years). Latent growth curve analysis revealed a progressive decline in self-regulatory efficacy from junior to senior high school, with males experiencing the greater reduction. The lower the decline in self-regulatory efficacy, the higher the high school grades and the greater the likelihood of remaining in high school controlling for socioeconomic status. Reciprocal cross-lagged models revealed that high perceived efficacy for self-regulated learning in junior high school contributed to junior high school grades and self-regulatory efficacy in high school, which partially mediated the relation of junior high grades on high school grades and the likelihood of remaining in school. Socioeconomic status contributed to high school grades only mediationally through junior high grades and to school drop out both directly and mediationally through junior high grades. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
In this paper, a hierarchical algorithm, HierarchyScan, is proposed to efficiently locate one-dimensional subsequences within a collection of sequences with arbitrary length. The proposed algorithm performs correlation between the stored sequences and the template pattern in the transformed domain to identify subsequences in a scale- and phase-independent fashion. This is in contrast to those approaches based on the computation of Euclidean distance in the transformed domain. In the proposed hierarchical algorithm, the transformed domain representation of each original sequence is divided into multiple groups of coefficients. The matching is performed hierarchically from the group with the greatest filtering capability to the group with the lowest filtering capability. Only those subsequences whose maximum correlation value is higher than a predefined threshold will be selected for additional screening. This approach is compared to the sequential scanning and an order-of-magnitude speedup is observed. 相似文献
73.
Vittorio Murino Andrea Trucco 《International journal of imaging systems and technology》1997,8(4):386-395
This article describes a probabilistic technique for the restoration of underwater acoustic images that is based on the Markov random fields (MRFs) methodology. The beamforming is applied to rough acoustic data that derive from multibeam systems or acoustic cameras to build a three-dimensional (3D) map, that is associated point by point with the estimates of the reliability of such measures. Specifically, backscattered echoes that are received by a 2D array antenna are arranged to generate two images in which each pixel represents the distance (range) from the sensor plane and the confidence of the measures, respectively. Unfortunately, this kind of image is affected by several problems due to the nature of the signal and the related sensing system. In the proposed algorithm, the range and the confidence images are modeled as separate MRFs whose associated probability distributions embed knowledge of the acoustic system, of the considered scene, and of the noise affecting the measures. In particular, the confidence image is first restored and the result is used to reconstruct the 3D image to allow an active integration of the reliability information. Optimal (in the maximum a posteriori probability sense) estimates of the reconstructed 3D map and the restored confidence image are obtained by minimizing the energy functionals, using simulated annealing. Experimental results on synthetic and real images show the performance of the proposed approach. © 1997 John Wiley & Sons, Inc. Int J Imaging Syst Technol, 8, 386–395, 1997 相似文献
74.
Vittorio Ricchiuti Pietro Ciammaichella 《International Journal of Communication Systems》1998,11(6):351-357
The ‘maximum (relative) time interval error’ (MRTIE(τ)) is one of the parameters most used by international standardization bodies to characterize the stability of the clocks in modern SDH synchronization networks. Besides the original definition of MRTIE(τ), ITU-T has introduced a new MRTIE(τ) definition of percentile character. This new definition allows linking of the MRTIE(τ) parameter to the stochastic noise processes affecting the clocks in synchronization networks. In this paper, after a brief discussion about the original and percentile definitions of MRTIE(τ), the study focuses on the output stability of a slave clock based on a phase-locked loop (PLL) system. A PLL with internal phase noise sources and fixed bandwidth value is considered. The output slave clock stability is studied when there is a step change in the phase of the PLL reference signal. The need to consider the MRTIE(τ) parameter not only as a simple measure of wander (slow phase fluctuations) but also as a measure of fast phase fluctuations (jitter) on the clocks is emphasized, in spite of the latest ITU-T recommendations and ETSI standards. © 1998 John Wiley & Sons, Ltd. 相似文献
75.
Michele Russo Gianpiero Forte Mario Montanino Oliva Antonio Simone Lagan Vittorio Unfer 《International journal of molecular sciences》2021,22(16)
Human pregnancy is a sequence of events finely tuned by several molecular interactions that come with a new birth. The precise interlocking of these events affecting the reproductive system guarantees safe embryo formation and fetal development. In this scenario, melatonin and myo-inositol seem to be pivotal not only in the physiology of the reproduction process, but also in the promotion of positive gestational outcomes. Evidence demonstrates that melatonin, beyond the role of circadian rhythm management, is a key controller of human reproductive functions. Similarly, as the most representative member of the inositol’s family, myo-inositol is essential in ensuring correct advancing of reproductive cellular events. The molecular crosstalk mediated by these two species is directly regulated by their availability in the human body. To date, biological implications of unbalanced amounts of melatonin and myo-inositol in each pregnancy step are growing the idea that these molecules actively contribute to reduce negative outcomes and improve the fertilization rate. Clinical data suggest that melatonin and myo-inositol may constitute an optimal dietary supplementation to sustain safe human gestation and a new potential way to prevent pregnancy-associated pathologies. 相似文献
76.
Pier Vittorio Aureli 《Architectural Design》2011,81(1):32-37
Pier Vittorio Aureli focuses on the category of archetype as an alternative to the idea of type. Four examples – the axial streets of Renaissance Rome, the 17th-century Parisian place, the 19th-century independent block in Berlin and the 20th-century Viennese superblock – are explored here to describe the emergence of modern urban forms that explicitly embody power relations. 相似文献
77.
78.
Russo P López P Capozzi V de Palencia PF Dueñas MT Spano G Fiocco D 《International journal of molecular sciences》2012,13(5):6026-6039
Probiotics, prebiotics and synbiotics are frequently-used components for the elaboration of functional food. Currently, most of the commercialized probiotics are limited to a few strains of the genera Bifidobacteria, Lactobacillus and Streptococcus, most of which produce exopolysaccharides (EPS). This suggests that the beneficial properties of these microorganisms may be related to the biological activities of these biopolymers. In this work we report that a 2-substituted-(1,3)-β-d-glucan of non-dairy bacterial origin has a prebiotic effect on three probiotic strains. Moreover, the presence of this β-d-glucan potentiates in vitro adhesion of the probiotic Lactobacillus plantarum WCFS1 to human intestinal epithelial cells. 相似文献
79.
HL Chen H Seol KJ Brown H Gordish-Dressman A Hill V Gallo R Packer Y Hathout 《International journal of molecular sciences》2012,13(7):9380-9399
To bring insights into neurofibroma biochemistry, a comprehensive secretome analysis was performed on cultured human primary Schwann cells isolated from surgically resected plexiform neurofibroma and from normal nerve tissue. Using a combination of SDS-PAGE and high precision LC-MS/MS, 907 proteins were confidently identified in the conditioned media of Schwann cell cultures combined. Label free proteome profiling revealed consistent release of high levels of 22 proteins by the four biological replicates of NF1 Schwann cell cultures relative to the two normal Schwann cell cultures. Inversely, 9 proteins displayed decreased levels in the conditioned media of NF1 relative to normal Schwann cells. The proteins with increased levels included proteins involved in cell growth, angiogenesis and complement pathway while proteins with decreased levels included those involved in cell adhesion, plasminogen pathway and extracellular matrix remodeling. Retinoic acid receptor responder protein-1 (RARRES1), previously described as an integral membrane tumor suppressor, was found exclusively secreted by NF1 Schwann cells but not by normal Schwann cells. All-trans retinoic acid modulated secretion of RARRES1 in a dose dependent manner. This study shows altered secretion of key proteins in NF1 derived Schwann cells. The potential implication of these proteins in neurofibroma biology is discussed. 相似文献
80.
Since the beginning of the last century, when Freud introduced the couch in the psychoanalytic room, a number of “objects” have been removed or renovated, yet the couch has almost always remained in place, at least officially. This article has two distinct aims. The first is to offer a reconstruction of the psychoanalytic history of this element of the setting. The second is to rethink the couch, saving it from being reduced to a mere icon. Recent contributions coming from affective neurosciences, infant research, and psychotherapy research seem to question the utility of this element and the nature of the very mechanisms of its therapeutic action. The authors wonder whether the use of the couch is primarily protective for the therapist rather than necessarily helpful for all patients. Taking into account these observations implies bringing the couch out from a silent dimension and reflecting on its role in the conception of therapeutic action and mental functioning. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献