Medical Image Registration and 3D Object Matching

The great challenge in image registration and 3D object matching is to devise computationally efficient algorithms for aligning images so that their details overlap accurately and retrieving similar shapes from large databases of 3D models. The first problem addressed is this thesis is medical image registration, which we formulate as an optimization problem in the information-theoretic framework. We introduce a viable and practical image registration method by maximizing an entropic divergence measure using a modified simultaneous perturbation stochastic approximation algorithm. The feasibility of the proposed image registration approach is demonstrated through extensive experiments. The rest of the thesis is devoted to a joint exploitation of geometry and topology of 3D objects for as parsimonious as possible representation of models and its subsequent application in 3D object representation, matching, and retrieval problems. More precisely, we introduce a skeletal graph for topological 3D shape representation using Morse theory. The proposed skeletonization algorithm encodes a 3D shape into a topological Reeb graph using a normalized mixture distance function. We also propose a novel graph matching algorithm by comparing the relative shortest paths between the skeleton endpoints. Moreover, we describe a skeletal graph for 3D object matching and retrieval. This skeleton is constructed from the second eigenfunction of the Laplace-Beltrami operator defined on the surface of the 3D object. Using the generalized eigenvalue decomposition, a matrix computational framework based on the finite element method is presented to compute the spectrum of the Laplace-Beltrami operator. Illustrating experiments on two standard 3D shape benchmarks are provided to demonstrate the feasibility and the much improved performance of the proposed skeletal graphs as shape descriptors for 3D object matching and retrieval

Enhancement of Antimicrobial Sensitivity of Salmonella and Escherichia coli Strains Isolated from Chickens Using Silver Nanoparticles in Assiut Governorate

Before the era of complete resistance to antibiotics due to their extensive use in poultry farms, new strategies were discovered, one of them was the use of nanoparticles to enhance the action of antibiotics. Therefore, this study was carried out to find out the antibacterial effect of silver nanoparticles (AgNPs) either separately or in combination with antibiotics. The obtained data showed the antibacterial activity of AgNPs against the tested Escherichia coli and Salmonella strains with MIC level of 0.85 µg/mL. Synergistic effects of AgNPs with antibiotics against E. coli revealed two-fold drop in MIC of ciprofloxacin and amoxicillin. Meanwhile, there was three-fold drop in MIC of gentamicin, cefotaxime and neomycin. Significant finding was observed in the case of the synergism of AgNPs with amoxicillin and gentamicin, the examined E. coli O2 resistant to amoxicillin and gentamicin became sensitive when the antibiotics were combined with AgNPs. It could be concluded that AgNPs can be easily produced by Rosemary aqueous extracts as low-cost, eco-friendly method for generating AgNPs. New generations of bactericidal compounds containing AgNPs could be successfully used in poultry farms for prevention and treating E. coli infections

Subgroup of the Jacobian of a Family of Superelliptic Curves

In this paper, we describe the structure of the subgroup generated by the images of the 2-sextactic points under the Abel- Jacobi map in the Jacobian of a 1-parameter family (Ca)a∈C\{0,1} of smooth projective plane curves of degree four. Each curve Ca ⊂ P2(C) of (Ca)a∈C\{0,1} is given b

Subgroup of the Jacobian of a Family of Superelliptic Curves

In this paper, we describe the structure of the subgroup generated by the images of the 2-sextactic points under the Abel- Jacobi map in the Jacobian of a 1-parameter family (Ca)a∈C\{0,1} of smooth projective plane curves of degree four. Each curve Ca ⊂ P2(C) of (Ca)a∈C\{0,1} is given b

Effect of Sperm Separation Methods on Morphology and Functions of Frozen Buffalo Spermatozoa

This work was planned to compare three methods for selection of active buffalo spermatozoa, examine the effects of these separation methods on morphology, viability and functions of spermatozoa used for IVF purposes. Ten frozen straws per trial (10 times) were pooled and divided into 4 aliquots:  A) First aliquot was considered as control without any separation method. B) Second aliquot was subjected to sperm selection by density gradient method (percoll:PureSperm) using 40-80% double density gradient. C) The third aliquot was subjected to swim-up in sp-TALP. D) The fourth aliquot was subjected to washing by centrifugation with sp-TALP. The percentage of motility increased for Percoll, swim up and washing than control (86.0, 73.0, and 66.5 vs. 56.5) respectively. Sperm abnormalities % was significantly decreased after Percoll, swim up and sperm wash separation methods. Spermatozoa obtained by Swim up and Percoll had the highest percentage of intact membrane. Different spermatozoa separation methods significantly increased the lytic activity of the recovered spermatozoa. Live spermatozoa percentage with reacted acrosome significantly increased after both swim up separation and washing. The percentage of dead spermatozoa with reacted acrosome significantly decreased after percoll separation but it did not change when the swim up method was used. Finally it is concluded that, density gradient centrifugation using PureSperm® could be considered as the method of choice for selection of frozen thawed buffalo spermatozoa and presumably with a high potential fertilizing ability. density gradient centrifugation using PureSperm® could be considered as the method of choice for selection of frozen thawed buffalo spermatozoa

Redox Regulation of Heart Regeneration: An Evolutionary Tradeoff

Heart failure is a costly and deadly disease, affecting over 23 million patients worldwide, half of which die within 5 years of diagnosis. The pathophysiological basis of heart failure is the inability of the adult heart to regenerate lost or damaged myocardium. Although limited myocyte turnover does occur in the adult heart, it is insufficient for restoration of contractile function1-6. In contrast to lower vertebrates which can regenerate their myocardium through cardiomyocyte proliferation,7-13, adult mammalian heart cardiomyogenesis very limited1-5. Studies in the late 90s elegantly demonstrated that mammalian cardiomyocytes continue to divide for a few days after birth 14-16, only to undergo permanent cell cycle arrest shortly thereafter. Recently, we demonstrated that resection of up to 15% of the apex of the left ventricle of postnatal day 1 (P1) mice results in complete regeneration within 21 days following injury, without significant fibrosis and cardiac dysfunction17. Moreover, we described a similar regenerative response following ischemic myocardial infarction 18. This response was well characterized by robust cardiomyocyte proliferation, with gradual restoration of normal cardiac morphology and function. In addition to the histological evidence of proliferating myocytes, genetic fate-mapping studies confirmed that the majority of newly formed cardiomyocytes are derived from proliferation of preexisting cardiomyocytes17. Intriguingly, this regenerative capacity is lost by P7, after which injury results in the cardiomyocyte hypertrophy and scar-formation, which coincides with binucleation and cell cycle exit of cardiomyocytes 14, 19. An important approach to understanding the loss of regenerative ability of the mammalian heart is to first consider why, and not only how, this happens. The regenerative ability of the early postnatal heart following resection or ischemic infarction involves regeneration of the lost myocardium and vasculature with restoration of normal myocardial thickness and architecture, and long-term functional recovery. Why would the heart permanently forego such a remarkable regenerative program shortly after birth? The answer may lie in within the fundamental principal of evolutionary tradeoff