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Virtual dissection of diffusion MRI tractograms is cumbersome and needs extensive knowledge of white matter anatomy. This virtual dissection often requires several inclusion and exclusion regions-of-interest that make it a process that is very hard to reproduce across experts. Having automated tools that can extract white matter bundles for tract-based studies of large numbers of people is of great interest for neuroscience and neurosurgical planning. The purpose of our proposed method, named RecoBundles, is to segment white matter bundles and make virtual dissection easier to perform. This can help explore large tractograms from multiple persons directly in their native space. RecoBundles leverages latest state-of-the-art streamline-based registration and clustering to recognize and extract bundles using prior bundle models. RecoBundles uses bundle models as shape priors for detecting similar streamlines and bundles in tractograms. RecoBundles is 100% streamline-based, is efficient to work with millions of streamlines and, most importantly, is robust and adaptive to incomplete data and bundles with missing components. It is also robust to pathological brains with tumors and deformations. We evaluated our results using multiple bundles and showed that RecoBundles is in good agreement with the neuroanatomical experts and generally produced more dense bundles. Across all the different experiments reported in this paper, RecoBundles was able to identify the core parts of the bundles, independently from tractography type (deterministic or probabilistic) or size. Thus, RecoBundles can be a valuable method for exploring tractograms and facilitating tractometry studies.

To investigate changes that e-coupons bring to consumers' coupon usage, the authors of this article developed and estimated models of coupon-usage intention. The models are based on the theory of reasoned action or the theory of planned behavior. Results show that the theory of planned behavior explains e-coupon usage intention better than the theory of reasoned action. On the other hand, the intention to use traditional coupons is effectively explained by the theory of reasoned action. Both perceived behavioral control and attitude toward Internet searching have significant effects on the intention to use e-coupons. Also, heavy users of e-coupons are different from those of traditional coupons. Light users of traditional coupons have relatively high intention to use

Abstract. The blood-brain barrier (BBB) is a complex functional barrier composed of endothelial cells, pericytes, astrocytic endfeets and neuronal cells. This highly organized complex express a selective permeability for molecules that bear, amongst other parameters, adequate molecular weight and sufficient liposolubility. Unfortunately, very few therapeutic agents currently available do cross the BBB and enters the CNS. As the BBB limitation is more and more acknowledged, many innovative surgical and pharmacological strategies have been developed to circumvent it. This review focuses particularly on the osmotic opening of the BBB, a well-documented approach intended to breach the BBB. Since its inception by Rapoport in 1972, pre-clinical studies have provided important information on the extent of BBB permeation. Thanks to Neuwelt and colleagues, the osmotic opening of the BBB made its way to the clinic. However, many questions remain as to the detailed physiology of the procedure, and its best application to the clinic. Using different tools, amongst which MRI as a real-time in vivo characterization of the BBB permeability and CNS delivery, we attempt to better define the osmotic BBB permeabilization physiology. These ongoing studies are described, and data related to spatial and temporal distribution of a molecule after osmotic BBB breaching, as well as the window of BBB permeabilization, are discussed. We also summarize recent clinical series highlighting promising results in the application of this procedure to maximize delivery of chemotherapy in the treatment of brain tumor patients.KEY WORDS: blood-brain barrier, blood-brain barrier disruption, brain tumors, CNS delivery; MRI.