Curve segmentation using directional information, relation to pattern detection

©2005 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or distribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.Presented at the 2005 International Conference on Image Processing (ICIP)September 11-14, 2005, Genova, Italy.DOI: 10.1109/ICIP.2005.1530175We propose an extension of the conformal (or geodesic) active contour framework in which the conformal factor depends not only on the position of the curve but also on the direction of its tangent. We describe several properties for variational curve segmentation schemes that justify the construction of optimal conformal factors (i.e., learning) in strong connection with pattern matching. The determination of optimal curves (i.e., segmentation) can be performed using either the calculus of variations or dynamic programming. The technique is illustrated on a road detection problem for different signal to noise ratios

Finsler Active Contours

©2008 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or distribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.DOI: 10.1109/TPAMI.2007.70713In this paper, we propose an image segmentation technique based on augmenting the conformal (or geodesic) active contour framework with directional information. In the isotropic case, the euclidean metric is locally multiplied by a scalar conformal factor based on image information such that the weighted length of curves lying on points of interest (typically edges) is small. The conformal factor that is chosen depends only upon position and is in this sense isotropic. Although directional information has been studied previously for other segmentation frameworks, here, we show that if one desires to add directionality in the conformal active contour framework, then one gets a well-defined minimization problem in the case that the factor defines a Finsler metric. Optimal curves may be obtained using the calculus of variations or dynamic programming-based schemes. Finally, we demonstrate the technique by extracting roads from aerial imagery, blood vessels from medical angiograms, and neural tracts from diffusion-weighted magnetic resonance imagery

Lake Ontario Atlas: Chemistry

The chemical and water quality characteristics of Lake Ontario reported prior to the International Field Year for the Great Lakes (IFTGL, 1972-1973) study have been reviewed and summarized. The low surface-to-volume ratio of this lake has allowed it to retain oligotrophic characteristics based upon biological parameters. However, some of the chemical paramerters, including the nutrient inputs and concentrations, suggest that eutrophication is imminent. In general, the water quality of Lake Ontario is good and projected increased in the loadings of major ions do not pose a threat to the use of this natural water resource during the rest of this century. The input of trace materials, such as the heavy metals and refractory organic compounds, is cause for concern since a significant contribution is made by an uncontrollable source, namely atmospheric precipitation. More stringent controls on the discharge of phosphorus, trace elements and synthetic organic compounds is recommended to preserve the integrity of Lake Ontario for the continued benefit of all users of its waters

Nuclear Ribosomal ITS Region Sequences for Differentiation of Rubus Genotypes

Previous molecular investigations into Rubus species diversity have yielded significant knowledge about species relatedness. However, little work has been focused at the cultivar level. Random amplified polymorphic DNA(RAPD)-PCR studies have successfully differentiated closely related cultivars. The ability to definitively distinguish blackberry and red raspberry cultivars based on other molecular methods could prove useful in many aspects of breeding and proprietary protection. In this study, the nuclear ribosomal DNA internal transcribed spacer regions (ITS) of six Rubus cultivars were sequenced. DNA sequencing revealed little genetic variation among blackberry cultivars, but revealed distinctions between blackberry and red raspberry cultivars. Analysis by maximum-parsimony and maximum-likelihood confirmed the small variation among blackberry cultivars, although cultivars Apache, Brazos, and APF-12 did organize a weak sub-cluster within the blackberry genotypes. However, ITS region sequences do not appear to differentiate among closely related blackberry genotypes for purposes of cultivar discrimination or plant patent protection

Bactericidal activity of extended 9-glycyl-amido-minocyclines

The need for self-protecting polymer or alloy implants resistant to a broad spectrum of bacterial challenges led us to investigate covalent bonding of minocycline (MIN), a tetracycline derivative, to polystyrene beads and to titanium alloy foils by oligoethylene glycol spacers. 9-Hydrazino-acetyl-amido-MIN, and simpler glycylcycline derivatives, retained minimum inhibitory concentration (MIC) against Staphylococcus aureus comparable to MIN. However, PEG-glycyl-amido-MIN showed very low activity. Hence, we coupled 9-hydrazino-acetyl-amido-MIN to the aldehyde termini of oligoethylene glycol spacers bonded to polystyrene and titanium alloy surfaces to form acid-releasable hydrazone linkages. 9-Hydrazino-acetyl-amido-MIN was released from the monolayers more rapidly at pH 5.0 than at pH 7.4