Automated detection of vascular structures is of great importance in understanding the mechanism, diagnosis, and treatment of many vascular pathologies. However, automatic vascular detection continues to be an open issue because of difficulties posed by multiple factors, such as poor contrast, inhomogeneous backgrounds, anatomical variations, and the presence of noise during image acquisition. In this paper, we propose a novel 2-D/3-D symmetry filter to tackle these challenging issues for enhancing vessels from different imaging modalities. The proposed filter not only considers local phase features by using a quadrature filter to distinguish between lines and edges, but also uses the weighted geometric mean of the blurred and shifted responses of the quadrature filter, which allows more tolerance of vessels with irregular appearance. As a result, this filter shows a strong response to the vascular features under typical imaging conditions. Results based on eight publicly available datasets (six 2-D data sets, one 3-D data set, and one 3-D synthetic data set) demonstrate its superior performance to other state-of-the-art methods.

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Recent studies have emphasized group creativity as a social-cultural conception, but they lack a focus on the relationship between group creativity and knowledge creation. This paper aims to build a framework for group creativity in a learning context which includes both theoretical understanding and empirical methodology. Thus, a literature review is led by the following questions: How has creativity theory been developed from individual to group level? From a social-cultural perspective, how can group creativity, knowledge creation, and their relationship be understood? And what methods have been employed to study group creativity? As the review demonstrates, creativity theory has been driven by new insights from recent sociology studies. Three focuses have been shaped from group creativity studies: 1) group creativity in context, 2) group-level creative synergy, and 3) strategies for developing group creativity. Individual knowledge is a potential resource for group creativity, and group creativity could be a driver of knowledge creation. Empirically, group creativity can be examined through both qualitative and quantitative approaches, which also calls for a creative combination of methodologies in future studies

Cooperative learning has many pedagogical benefits. However, if the cooperative learning teams become ineffective, these benefits are lost. Accordingly, this study developed a computer-aided assessment method for identifying ineffective teams at their early stage of dysfunction by using the Mahalanobis distance metric to examine the difference between the sequential test scores of the unknown team and the test scores of a reference group of functioning teams. The effectiveness of the proposed method was verified by conducting field experiments over an 18-week engineering course in Taiwan. Forty-eight students were randomly assigned to cooperative learning teams. The students' learning performance was evaluated by means of unit tests and homework tests. The functioning of the cooperative teams was examined at seven different points during the course of the study. The ineffective teams were identified with quantified type I errors. It was found that some teams failed persistently. Such teams require some form of external intervention to remedy the group dynamics. The results also showed that teams can become ineffective at any stage of the cooperative learning process. Thus, continuous monitoring is required to ensure that appropriate remedial actions are taken in a timely manner.

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The mechanical discontinuities in the upper crust (i.e., faults and related fractures) lead to the uprising of geothermal fluids to the Earth’s surface. If fluids are enriched in Ca2+ and HCO3-, masses of CaCO3 (i.e., travertine deposits) can form mainly due to the CO2 leakage from the thermal waters. Among other things, fissure-ridge-type deposits are peculiar travertine bodies made of bedded carbonate that gently to steeply dip away from the apical part where a central fissure is located, corresponding to the fracture trace intersecting the substratum; these morpho-tectonic features are the most useful deposits for tectonic and paleoseismological investigation, as their development is contemporaneous with the activity of faults leading to the enhancement of permeability that serves to guarantee the circulation of fluids and their emergence. Therefore, the fissure ridge architecture sheds light on the interplay among fault activity, travertine deposition, and ridge evolution, providing key geo-chronologic constraints due to the fact that travertine can be dated by different radiometric methods. In recent years, studies dealing with travertine fissure ridges have been considerably improved to provide a large amount of information. In this paper, we report the state of the art of knowledge on this topic refining the literature data as well as adding original data, mainly focusing on the fissure ridge morphology, internal architecture, depositional facies, growth mechanisms, tectonic setting in which the fissure ridges develop, and advantages of using the fissure ridges for neotectonic and seismotectonic studies.