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Extraction of features from images has been a goal of researchers since the early days of remote sensing. This paper presents a statistical approach to detect dark curvilinear features due to ocean disturbances caused by wind, movements of surface or underwater objects, and oil spill from SAR images. The image is first enhanced to emphasize the dark curvilinear features using a statistical approach. Then, the curvilinear features are segmented using an iterative approach. The holes in the segmented image are then filled using a recursive scanning method. The image is thinned and unwanted branches are removed using a graph-theory-based technique. Finally, an efficient linking algorithm based on geometric properties is proposed to detect the disturbance features. Our algorithm is evaluated using on both synthetic images with by various levels of added Gaussian noise and on actual SAR images from ERS-2, SEASAT, ENVISAT, and RADARSAT. The results of our approach is compared with those from existing approaches. Results show that, in comparison with the algorithms in literature, our algorithm is more accurate in extracting the features both in terms of the area and shape. In addition, our algorithm runs significantly faster. [ABSTRACT FROM PUBLISHER]

The present study describes the activity of a nanomaterial on protoscoleces of Echinococcus granulosus, which exhibited morphological changes and apoptosis. Apoptotic changes were deduced on the basis of effector caspase activation and nucleosomal laddering. Invaginated protoscoleces maintained in vitro became evaginated and had hooks, presumptive suckers and stalks. Degenerative changes of protoscoleces were evidenced after treatment with praziquantel and nano-combination. Protoscoleces treated with praziquantel had distinct attestation of necrosis and nano-combination-treated protoscoleces had signatures of apoptosis. [ABSTRACT FROM PUBLISHER]

Object classifier often operates by making decisions based on the values of several shape properties measured from an image of the object. The paper introduces a unique definition of measure for 2-D geometrical object shape detection. Using this definition different object shapes can be identified on the basis of their degree of fitness parameter. Basically, we have fitted a 2-D polygon/curve on the object as a best fitted polygon/curve and computed the parameter degree of fitness which is the ratio of the matching area and non-matching area due to the fitted polygon/curve and the object both. The results show the effectiveness of the proposed measure. [ABSTRACT FROM AUTHOR]

1. The inheritance of various plumage colour variants and their underlying interactions were investigated in a large flock of Japanese quail maintained at CARI (India) by conducting reciprocal crosses between four breeding stocks inheriting Pharaoh, White Breasted, White and Brown plumages, followed by test crosses. 2. Based on the proportion of plumage-colour types in the progeny, putative genotypes were determined for parents and offspring for each of the crosses. 3. The White and Brown phenotypes were attributed to the Panda (S) and Roux (Br) loci respectively in agreement with contemporary quail stocks. 4. The White Breasted plumage type present in our stock was caused by a novel mutation with dominant gene action at an autosomal locus that was not allelic to either Panda or the White feather locus. 5. A recessive epistatic action of the Panda locus (S) on White Breasted (Wb) resulted in a White colour phenotype. 6. A novel phenotype, White Breasted-Brown was co-expressed with the Br and Wb loci. 7. It was concluded that breeding for customized feather colour phenotypes in Japanese quail using colour mutations was feasible and would be advantageous in order to overcome the limitations of legislation to protect wildlife in India. [ABSTRACT FROM PUBLISHER]

Circular or elliptic fit of an object is important in target detection, shape analysis, and biomedical image analysis problems. Here, the problems of fitting circle or ellipse to an object in 2-D are considered. At first, the problems is converted to quadratic equation of single unknown by some constraints. Then its solutions for all the border points of the object are found and averaged. The major and minor axes of ellipse are presented by least sum perpendicular distance of all points of the object. The other unknowns are found using the equations of constraints. In the proposed method, the main constraint used for the circular and elliptic fit is that the area of the fitting circle or ellipse is equal to the area of the object to be fitted. The approach appears to be less sensitive to the object border noise and is computationally attractive. Some examples are presented to show the effectiveness of the approach. A measure of degree of circularity, ellipticity, etc in fuzzy set theoretic framework is also proposed. [ABSTRACT FROM AUTHOR]

The following result gives a partial answer to a question of R. M. Wilson regarding the existence of group divisible designs of large order. Let k and u be positive integers, 2⩽k⩽u. Then there exists an integer m0=m0(k, u) such that there exists a group divisible design of group type mu with block size k and index one for all integer m⩾m0 if and only if (i) u−1≡0 mod(k−1), (ii) u(u−1)≡0 mod k(k−1). This is a generalization of the well-known result of Chowla, Erdo˝s, and Straus on the existence of transversal designs of large order. [Copyright &y& Elsevier]

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Recurrence of kala-azar after post kala-azar dermal leishmaniasis (PKDL) has remained uncommon. We report here two patients with recurrence of kala-azar (KA) after development of PKDL. In one case the second attack of KA was preceded by repeated attacks of malaria and tuberculosis, and in the other the recurrence of KA followed an attack of measles. While measles has earlier been suggested as co-factor in inducing transformation from sub-clinical to clinical kala-azar, malaria was demonstrated to enhance the virulence and invasiveness of Leishmania in an experimental model as well as under natural condition. We propose that in our cases, measles and repeated attacks of malaria or tuberculosis led to immunosuppression and recurrence of visceral leishmaniasis (VL). [ABSTRACT FROM AUTHOR]