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The thesis entitled “Exploring Intermolecular Space by Charge Density Analysis in Molecular Crystals” consists of five chapters. A short introductory note highlights the importance of intermolecular interactions and presents the current status of charge density analysis to obtain insights into such interactions. Charge density analysis of crystalline materials by using high resolution X-ray diffraction data has become routine and enables derivation of reliable one electron properties associated with the electron density. The results obtained from single crystal X-ray diffraction data at low temperature have been compared with periodic theoretical calculations using B3LYP/6-31G** methods to unequivocally establish the nature of weak interactions. Chapter 1 describes the quantitative analysis of Cl∙∙∙Cl intermolecular interactions in compounds 2-chloro-3-quinolinyl methanol, 2-chloro-3-hydroxypyridine and 2-chloro-3-chloromethyl-8-methylquinoline, which are corresponding to type I (trans and cis) and type II (L) geometries of Cl∙∙∙Cl interactions respectively. The 3D static deformation density plots from charge density analysis unequivocally suggest that both ‘cis’ and ‘trans’ type I geometries show decreased repulsion whereas type II geometry is attractive based on the nature of “polar flattening” of the electron density around the Cl atom. The topological features derived at bond critical point (BCP) of Cl∙∙∙Cl interactions also support the observed results. Chapter 2 discusses hetero-halogen (Cl∙∙∙F) and homo-halogen (F∙∙∙F) intermolecular interactions involving “organic fluorine” in compounds 2-chloro-4-fluorobenzoic acid and 4-flurobenzamide respectively. Charge density distributions show polar flattening effects at both atoms Cl and F, however the extent of polarization is small on F in comparison with that of the Cl atom. 3D static deformation density plots depict δ+ ∙∙∙δ− interactions for Cl∙∙∙F intermolecular interactions while F∙∙∙F interactions show small decreased repulsion features. The topological properties of F∙∙∙F interactions bring out the similarity between F∙∙∙F and Cl∙∙∙Cl interactions. Chapter 3 describes the nature of C−Cl∙∙∙O=C halogen bond in 2, 5-dichloro-1, 4-benzoquinone, a molecule specifically chosen to depict this interaction dominantly. The topological values at bond critical point, three dimensional static deformation density features and electrostatic potential isosurfaces unequivocally establish the attractive nature of C−Cl∙∙∙O=C halogen bond in the crystalline lattice. Chapter 4 discusses the generation of multi-component systems (for example cocrystals and salts) of active pharmaceutical ingredients (API). Two systems associated with nicotinamide, one with salicylic acid and the other with oxalic acid as coformers resulting in 1:1 molecular complexes have been analyzed. The charge density analysis, particularly at the proton transfer region clearly bring out the differences between cocrystal and salt thus providing insights into the continuum in the proton transfer pathways in molecular crystals. Chapter 5 describes a new methodology [supramolecular synthon based fragment approach (SBFA)] concerning transferability of experimental charge density multipole parameters and building a database using well defined supramolecular synthons. The modularity and robustness of supramolecular synthons are used to transfer experimental charge density multipole parameters of synthons derived from a high resolution X-ray diffraction study to target molecules possessing these synthons as fragments in the crystalline lattice. The synthesized charge density and derived topological properties on target molecules using routine single crystal diffraction data are comparable with both experimental and theoretical charge density results. SBFA thus is expected to provide an additional database which can be applied to include intermolecular interactions space in the modeling directly unlike the available ones such as ELMAM, INVARIOM and UBDB. Further, SBFA approach can be extended to the determination and synthesis of charge density properties in macromolecules such as polypeptides, nucleic acids and proteins. APPENDIX contains reprints of the articles published which comprises of the work carried out in addition to the above five chapters.

This thesis examines banking efficiency and the productivity of thirteen transition Central and Eastern European banking systems during 1998-2003 using Data Envelopment Analysis (DEA). It proposes a non-parametric methodology for non-radial Russell output efficiency measure of banking firms, incorporating risk as an undesirable output. In addition, the proposed efficiency measure handles unrestricted data, i. e. both positive and negative. The Luenberger productivity index is suggested, which is applicable to technology where the desirable and undesirable outputs are jointly produced, and are possibly negative. Furthermore, the thesis addresses the main issue in the literature on banking performance measurement, which concerns the lack of consistency in the conceptual and theoretical considerations in describing the banking production process. Consequently, a metaanalysis tool, to examine the choice of inputs and outputs definitions in the banking efficiency literature, is suggested. In addition, the performance measures are estimated using three alternative definitions of the banking production process focusing on the risk and environmental dimensions of bank efficiency and productivity, with further comparative analysis using bootstrapping and kernel density techniques. Overall, the empirical results suggest that in Central and Eastern Europe Czech, Hungarian and Polish banks were the most technical efficient banks and the banking risk was mainly affected by external environmental factors during the analyzed period. Productivity analysis implies that the main driver of productivity change in the Central and Eastern European banks is the technological improvement. As meta-analysis revealed, the choice of particular approach of describing the banking production process is determined not by the availability of particular input or output variable information but the concepts of researcher's theoretical considerations. Statistical tests and density analysis indicate that efficiency scores, returns parameters and productivity indexes are sensitive to the choice of particular approaches.

The thesis entitled “Addressing subtle physicochemical features exhibited by molecular crystals via Experimental and Theoretical Charge Density Analysis” consists of five chapters. An introductory note provides a brief description of experimental and theoretical charge density methodology, followed by its utilization in obtaining certain physical and chemical properties in molecular crystals. Chapter 1 addresses not so easily accessed molecular property arising due to electron conjugation, highlighting antiaromaticity in tetracyclones. A systematic study of six tetracyclone derivatives with electron withdrawing and electron donating substituents has been carried out using experimental and theoretical charge density analysis. A three pronged approach based on quantum theory of atoms in molecules (QTAIM), nucleus independent chemical shifts (NICS), and source function (SF) has been employed to establish the degree of antiaromaticity of the central five-membered ring in all the derivatives. Electrostatic potentials mapped on the is density surface reveal the finer effects of different electron withdrawing and electron donating substituents on the carbonyl group. Chapter 2 presents a temperature induced reversible first order single crystal to single crystal phase transition (Room temperature Orthorhombic, P22121 to low temperature Monoclinic, P21) in a  hybrid peptide, Boc-γ4(R)Val-Val-OH. The thermal behavior accompanying the phase transition of the dipeptide crystal was characterized by differential scanning calorimetry, visual changes in birefringence of the sample during heating and cooling cycles on a hot-stage microscope with polarized light. Variable-temperature unit cell check measurements from 300 to 100 K showed discontinuity in the volume and cell parameters near the transition temperature, supporting the first-order behavior. The reversible nature of the phase transition is traced to be due to an interplay between enthalpy and entropy. Chapter 3 brings out an unusual stabilizing interaction involving a cooperative -hole and ¬hole character in a short NCS···NCS bond. This chapter describes structural features of four isothiocyanate derivatives, FmocXCH2NCS; X=Leu, Ile, Val and Ala. Among these it is observed that only FmocLeuCH2NCS which crystallizes in a tetragonal space group, P41, (a=b=12.4405(5) Å; c= 13.4141(8) Å) transforms isomorphously to a low temperature form, P41, (a=b=17.4665(1) Å; c= 13.1291(1) Å). The characteristics of the phase transition have been monitored by Differential Scanning Calorimetry, variable temperature IR and temperature dependent unit cell measurements. The short NCS···NCS intermolecular interaction (3.296(1) Å) is analyzed based on detailed experimental charge density analysis which reveals the nature of this stabilizing interaction. Chapter 4 explains a comparative study of syn and anti conformations of carboxylic acids in peptides from both structural aspect and charge density features. Single crystal structures of four peptides having syn conformations [BocLeuγ4(R)Valγ4(R)ValOH, BocLeuγ4(R)ValLeuγ4(R)ValOH, Boc3(S)Leu3(S)LeuOH] and one with anti conformation, BocLeuγ4(R)ValValOH have been analyzed. Experimental charge density analysis has been carried out exclusively on BocLeuγ4(R)ValValOH having anti form, because of its rare occurrence in literature. However, low temperature datasets on the four peptides with syn conformations were collected and theoretical charge density analysis has been carried out on two of these compounds. Electrostatic potentials mapped on is density surface bring out a significant difference at the oxygen atoms of the carboxyl group in the two conformations. However, lone pair orientation of different types of Oxygen atoms in the two forms (urethane, amide, acid) doesn’t exclusively indicate the differences in the corresponding charge density features. Chapter 5 addresses the issue of how sensitive are the charge density features associated with amino acid residues when the backbone conformational angles are varied. Three model systems, 1, L-alanyl–L-alanyl–L-alanine dehydrate; 2, anhydrous L-alanyl–L-alanyl–L¬alanine and 3, cyclo-(D,L-Pro)2(L-Ala)4 monohydrate have been chosen for this evaluation. Compound 1 has ant parallel alignment of tripe tide strands, and compound 2 has parallel alignment. All the alanine residues in compound 1 and 2 are in the -sheet region of the Ramachandran plot, whereas, the four Alanine residues in the cyclic hex peptide 3 span different regions of the Ramachandran plot. Theoretical multipole modelling has been carried out in order to explore the plausibility of transferring multipole parameters across different regions of Ramachandran Plot. Appendix I contains a brief description of charge shift bonding in Ph-CH2-Se-Se-CH2-Ph, as determined based on both experimental and theoretical charge density analysis. Appendix II contains a reprint of a published article on “Conformation-Changing Aggregation in Hydroxyacetone: A Combined Low-Temperature FTIR, Jet, and Crystallographic Study”.

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Baigiamojo darbo tikslas – radiolokatoriaus elektromagnetinio spinduliavimo srauto tankio skaičiavimas bei analizė, remiantis Europos Sąjungos bei Lietuvos higienos normomis impulsiniams elektromagnetinės spinduliuotės šaltiniams. Skaičiavimo ypatybė ta, kad atsižvelgiama į reljefo įtaką srauto kitimui erdvėje. Tyrimui naudojama Matlab duomenų analizės programa suteikia galimybę gauti maksimalų tikslumą bei ištirti galimą antenos aukščio mažinimą, neviršijant higienos normoje nustatyto 10µW/cm2 vidutinio elektromagnetinio srauto tankio vertės 1,5 m aukštyje gyvenamojoje zonoje. Parašytas programos kodas leidžia analizuoti bet kokio reljefo įtaką pasirinkto radiolokatoriaus spinduliavimo parametrams. Rezultatuose pateikiami dvimačiai bei trimačiai grafikai kaip pagrindą naudojant Palangos oro uosto teritorijos išplanavimą, taip pat skaičiavimai menamam reljefui bei esant skirtingiems antenos aukščio parametrams. Magistriniame darbe nustatyta, kad tiriamo radiolokatoriaus darbo zona atitinka higienos normas net ir sumažinus anteną iki minimalaus aukščio. Aptariami spinduliavimo mažinimo būdai, alternatyvių sistemų galimybė. / The object of this thesis is evaluation and analysis of spatial radar electromagnetic radiation density with reference to EU and Lithuania Hygiene Norm for pulse electromagnetic wave emitters. Relief influence on spatial electromagnetic radiation density distribution is taken into account. Calculations and analysis are processed using Matlab data analysis program and allows to upscale the precision and manipulate antenna height to reach its minimum value without exceeding 10μW/cm2 radiation density for inhabited area at a height of 1,5m as directed by Hygiene Norm. Written Matlab script enables to analyze various relief influence on a range of radar performance. Results are produced in the form of two and three dimensional charts having Palanga airport area as a base for building layout as well as the results for artificial relief including variable height of antenna. Results brought the conclusion of analyzed radar to be well ahead of the Hygiene Norm even with the minimum antenna height. Possible methods of minimizing radiation are explained in conjunction with new alternative aircraft detection systems being introduced.

The thesis entitled “Unravelling the Nature of Halogen and Chalcogen Intermolecular Interactions by Charge Density Analysis" consists of five chapters. A basic introductory section describes the topics relevant to the work and the methods and techniques utilized. The main focus of the present work is to characterize the interaction patterns devoid of strong classical hydrogen bonds. The case studies include halogen bonds and hydrogen bonds involving bromine (as a halogen bond donor and hydrogen bond acceptor), intermolecular chalcogen bond formation involving sulphur, type I Br Br contacts, type II F F and F S interactions and S-H S hydrogen bonds. Chapter 1 discusses experimental and theoretical charge density analyses on 2,2-dibromo-2,3-dihydroinden-1-one which has been carried out to quantify the topological features of a short C Br···O halogen bond with nearly linear geometry (2.922Å, C Br···O=172.7) and to assess the strength of the interactions using the topological features of the electron density. The electrostatic potential map indicates the presence of the “- hole” on bromine while the interaction energy is comparable to that of a moderate O-H O hydrogen bond. In addition, the energetic contribution of C-H···Br interaction is demonstrated to be on par with that of the C-Br···O halogen bond in stabilizing the crystal structure. Chapter 2 discusses an organic solid, 4,7-dibromo-5,6-dinitro-2,1,3-benzothiadiazole that has been designed to serve as an illustrative example to quantitatively evaluate the relative merits of halogen and chalcogen bonding in terms of charge density features. The compound displays two polymorphic modifications, one crystall zing in a non-centrosymmetric space group (Z =1) and the other in a centrosymmetric space group with two molecules in the asymmetric unit (=2). Topological analysis based on QTAIM clearly brings out the dominance of chalcogen bond over the halogen bond along with an indication that halogen bonds are more directional compared to chalcogen bonds. The cohesive energies calculated with the absence of both strong and weak hydrogen bonds as well as stacking interaction are indicative of the stabilities associated with the polymorphic forms. Chapter 3 discusses the role of a type I C-Br Br-C contact and what drives the contact i.e. how a dispersive interaction is stabilized by the remaining contacts in the structure. In the process we observe the role the Br2Cl motif which is quite unique in its nature. Also the role of the bromine atoms in stabilizing the stacking interactions has been shown by the electrostatic potentials which are oriented perpendicular to the plane of the benzene ring. Chapter 4 discusses the enigmatic type II C-F F-C and C-FS-C interactions in pentafluorophenyl 2,2- bithiazole. Both the interactions are shown to be realistic “-hole” interactions based on high resolution X-ray charge density analysis. As fluorine is the most electronegative element, its participation in halogen bonding wherein the electrostatic potential around the atom gets redistributed to form regions of electron depletion and accumulation had time and again been speculated but never observed. In this chapter the experimental charge dnsity analysis clearly identifies the “-hole” on fluorine and distinguishes the C-F S-C interaction as a halogen bond rather than the chalcogen bond. Chapter 5 discusses the experimental charge density analysis of the hitherto unexplored S-H S hydrogen bond in crystal structures. The work highlights how relatively small is the number of crystal structures which are constructed by the S-H S hydrogen bond compared to the X-H S hydrogen bond via Cambridge Structural Database (CSD) analysis. The potential S-H S hydrogen bond is studied in three isomeric mercaptobenzoic acids with experimental charge density collected on 2-mercaptobenzoic acid and theoretical estimates made on 3- and 4-mercaptobenzoic acid. The strength and directionality of the S-H S hydrogen bond is demonstrated to be mainly due to the conformation locking potential of intramolecular S O halogen bond.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A anÃlise de imagens mÃdicas por meio de tÃcnicas de visÃo computacional tornou-se bastante promissora, principalmente pelo fato de aperfeiÃoar a acurÃcia diagnÃstica de diversas patologias. Por essas razÃo, a Pneumologia à considerada atualmente uma Ãrea de concentraÃÃo de projetos que envolvem mÃtodos de Processamento Digital de Imagens. A segmentaÃÃo de vasos sanguÃneos pulmonares à de bastante auxÃlio na detecÃÃo de cardiopatias pulmonares. Esse processo à realizado atravÃs da anÃlise dos resultados obtidos por exame de diagnÃstico por imagem, os quais se destacam as radiografias torÃcicas, tomografia computadorizada (TC) do tÃrax, ressonÃncia magnÃtica, cintilografia pulmonar e angiografia. A hipertensÃo pulmonar e o cÃncer sÃo exemplos de doenÃas que podem ser diagnosticadas com menor subjetividade ao realizar a segmentaÃÃo de vasos, visualizaÃÃo em trÃs dimensÃes e extraÃÃo de seus atributos. Devido a essa importÃncia, diversos algoritmos sÃo desenvolvidos com intuito de obter uma segmentaÃÃo Ãtima destas estruturas. Dentre estes, encontram-se os mÃtodos por contornos ativos, LÃgica Fuzzy, Crescimento de RegiÃes, Filtragem Multi-escalar 3D e algoritmo Expectation Maximization (EM). Nesta dissertaÃÃo, sÃo segmentados os vasos sanguÃneos pulmonares de imagens de tomografia computadorizada do tÃrax utilizando-se trÃs mÃtodos: uma combinaÃÃo de Crescimento de RegiÃes 3D controlado por uma funÃÃo de pertinÃncia gaussiana e limiarizaÃÃo; um mÃtodo hÃbrido de segmentaÃÃo por Conectividade Fuzzy e limiarizaÃÃo; por m, a segmentaÃÃo utilizando o classicador K-mÃdias. Os resultados obtidos pelas segmentaÃÃes sÃo analisados e comparados por meio de uma anÃlise dos coecientes de similaridade e sensibilidade. Os resultados da aplicaÃÃo dos trÃs mÃtodos sÃo caracterizados aceitÃveis e compatÃveis com os observados na literatura. / Medical image analysis using computer vision techniques has become quite promising because of its improvement on the diagnostic accuracy of various pathologies. For this reason, pulmonology became an area of high concentration of projects involving methods of Digital Image Processing. The blood vessels segmentation in the lung is an important aid in the detection of pulmonary heart diseases. This process is performed by analyzing the results obtained with known diagnostic imaging exams, like chest Xrays, computed tomography (CT) scan, magnetic resonance imaging, scintigraphy and angiography. Pulmonary hypertension and cancer are examples of diseases that can be diagnosed with less subjectivity if performing vessels segmentation, three-dimensional visualization and attribute extraction of these images. Thus, several algorithms are developed with the objective of obtaining an optimal segmentation of these structures. Among those algorithms are active contours, fuzzy logic, 3D Region Growing, 3D multi-scale ltering algorithm and Expectation Maximization (EM). In this study, the blood vessels were extracted from lung CT scans of the chest using three methods. The rst is a combination of 3D Region Growing controlled by a Gaussian membership function and thresholding, the second is a hybrid segmentation by thresholding and Fuzzy Connectedness. Finally,the third refers to segmentation using the K-means classier. The results and evaluation of applying these algorithms are presented.

Coral reefs are an important resource world-wide. Unfortunately, coral reef conditions are declining in many areas due to both global and local stressors. The objective of this study was to survey stakeholders in southeast Florida to better understand reef use in the region. Stakeholders spatially identified where and how often they conducted their activities. These data were compiled and analyzed in GIS to determine spatial use patterns. Both location and intensity of use were analyzed to determine which areas may be under greater stress from recreational activities. It was found that reef use was not evenly distributed in the region but clustered around inlets and piers. Reef use differed between user groups (i.e. SCUBA divers, fishers) and demographics. It was also found that use in the Broward-Miami Coral Reef Ecosystem Region was spread out over a wider spatial scale than the use in the regions north and south.. These data are important as they have the potential to inform the recommendations being made to improve coral reef management in southeast Florida. The study can provide a better understanding of human-environmental relationships and the trade-offs involved so that recommendations can better decrease user conflicts, maximize economic productivity, and preserve the environment.

The largest Florida manatee (Trichechus manatus latirostris) aggregation at a natural warm-water refuge occurs in Kings Bay, Crystal River, FL. Over the last 32 years, the U.S. Fish and Wildlife Service and the State of Florida have created a network of manatee protection areas within Kings Bay including a year-round refuge designation and seven Federal manatee sanctuaries during the winter manatee season (November 15 – March 31). Aerial survey data collected between 1983 and 2012 was used to examine the seasonal change in manatee distribution within Kings Bay in order to assess the effectiveness of current sanctuary sizes and locations. Regression analysis indicated a significant change in manatee abundance among the winter seasons (p < 0.05). The average winter manatee counts increased by 4.81 animals per year over the 30 year period. In contrast, no significant changes in average or peak manatee abundance was detected among the summer seasons (p = 0.71 and p = 0.45 respectively). The average manatee counts increased by only 0.109 animals per year over the summer periods. Spatially explicit models using Geographic Information System (GIS) analysis revealed a strong correlation between high manatee density and artesian springs during the winter seasons. Highest abundances were identified at three locations: King’s Spring, Three Sisters Springs, and Magnolia Springs. These three locations coincide well with pre-existing sanctuary designations, but additional coverage is needed to support the overflow of manatees outside of sanctuary boundaries. Manatees continued to use Kings Bay in the summer seasons but in lower numbers and densities. Because density patterns were not uniform across summer periods, a heavier reliance on boat speed regulation is recommended to provide adequate protection to the endangered Florida manatee. Within a habitat type, the Magnolia Springs, South Banana Island, and Three Sisters Springs sanctuaries exhibited a significant influence on manatee density, suggesting differences in quality among sanctuaries. Years coinciding with extreme cold weather events also had a significant influence on manatee density. Using GIS to investigate seasonal shifts in manatees can be very informative regarding many issues including habitat selection and may improve the design and management of protected areas.