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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
291

The effect of chiropractic spinal adjustive therapy of the cervical and/or upper thoracic spine on eye-hand co-ordination

Ross, Stuart Paul 11 October 2011 (has links)
M.Tech. / The aim of this study was to determine whether Chiropractic cervical spine and/or upper thoracic adjustments had an effect on eye-hand co-ordination in asymptomatic participants presenting with cervical and/or upper thoracic spine dysfunction. Forty eight asymptomatic participants took part in this study. The participants were divided into three groups of sixteen participants each, each group consisting of eight male and eight female participants. Group 1 participants received Chiropractic adjustive therapy to dysfunctional segments in the C0-C3 spinal segments and C5-T1 spinal segments. In Group 2 the participants received Chiropractic spinal adjustive therapy to dysfunctional spinal segments in the C0-C3 region. Group 3 acted as the control group and participants received detuned ultrasound applied to the posterior cervical spine region. Two computer tests were involved in this study, namely the 2HAND test and the B19 test which had to be completed successively. The subjects were allowed to have a trial run each time they were tested to get a “hand’s-on feel” for the equipment. After the trial run the participants were tested, their respective treatment was carried out and the participants were then re-tested. Overall the study was able to show that Chiropractic adjustive therapy had no effect on eye-hand co-ordination in asymptomatic participants. Group 1 did not show any greater improvement in eye-hand co-ordination when compared to Group 2 where Group 1 received upper cervical spine and upper thoracic adjustments and Group 2 received only upper cervical adjustments. Gender was seen to play a significant role in the study, mainly during the B19 test. Overall it can be said that Chiropractic adjustive therapy had no effect on speed (OMD) or accuracy (OPED) during the test. Future research is needed on the possible effects of Chiropractic adjustive therapy on speed and accuracy as the study design showed some potential positive influences but may have been merely due to coincidence because of the small sample sizes. When testing eye-hand co-ordination it was noted that after the participants received Chiropractic adjustive therapy the length of mistakes in percent (LMP) decreased, meaning that the participants were able to correct any mistakes made at a faster rate after receiving Chiropractic adjustive therapy, but only when delivered to the spinal levels C0-C3 and/or C5-T1 (i.e. Group 1) for male participants only. Statistically significant results were noted when testing the number of mistakes made (NM) but only for male participants receiving Chiropractic adjustments to the C0-C3 levels only (i.e. Group 2). Future research needs to be done on the gender discrepancies noted for the different manner that Chiropractic adjustive therapy affected the different genders.
292

Contrôle de la stéréochimie du centre Ln dans des complexes base de Schiff 3d-4f : application à l'élaboration de molécules-aimants chirales / Control the stereochemistry of the Ln center in 3d-4f schiff base complexes : application to the development of chira molecule magnets

El Rez, Bahjat 06 February 2015 (has links)
Dans le cadre de cette thèse de doctorat nous nous sommes intéressés à la préparation de composés moléculaires magnétiques chiraux dont le centre métallique, siège de l'anisotropie magnétique, est également centre de chiralité. Notre étude a porté sur le contrôle de la stéréochimie du polyèdre de coordination d'un ion Ln, en particulier dans des complexes base de Schiff 3d-4f. L'approche originale que nous avons explorée consiste à induire la stéréochimie du centre Ln par un ligand-chélate anionique chiral directement lié au métal. L'anion-ligand que nous avons considéré est la forme déprotonée du trifluoroacétyl-3-camphre (abrégée Camph-). Pour des complexes de type base de Schiff 3d-4f, deux anions chiraux viennent s'ancrer sur l'ion Ln et, par transfert de chiralité, permettent de fixer la stéréochimie de la sphère de coordination de la terre-rare. Une stéréochimie Delta ou Lambda est ainsi obtenue en fonction de l'énantiomère de l'anion-chiral mis en œuvre dans la synthèse. Cette approche a permis la synthèse de plusieurs familles de composés énantiopurs (ex. [LMe2Ni(H2O)Ln(camph)2(CF3SO3)]; [LMe2Zn(Cl)Ln(camph)2(MeOH)]). Dans chaque cas une stéréochimie Lambda est associée à l'énantiomère R-(+) de l'anion chiral et une stéréochimie Delta à l'énantiomère S-(-). Cependant une telle stéréo-sélectivité n'est pas systématique, la dissymétrie de l'espace de la sphère de coordination de la terre-rare associée à son troisième anion ou à un ligand ancillaire semble jouer un rôle important.Selon la même approche, nous avons également considéré la préparation de complexes 4f mono-métalliques chiraux de formulation [Ln(Camph)4]-. L'étude des comportements magnétiques a mis en évidence des comportements de type SMM (Single Molecule Magnet) pour plusieurs composés contenant les ions Tb ou Dy. / The research work described in this thesis deals with the design, the synthesis and magnetic property investigation of magnetic low dimensional molecular materials (i.e. single Molecule Magnets, SMM), especially in 3d-4f Schiff-base complexes, involving magnetically anisotropic lanthanide (Ln) metal centers in conjunction with chirality. The aim of this investigation was to provide an efficient access to enantiopure SMMs chiral at metal (Ln). We developed an original chemical approach that consists in introducing a chiral chelating diketonate ligand directly bonded to the Ln metal center. Thus transfer of chirality from chiral ligand to the coordination polyhedron of the metal center can be achieved. Deprotonated 3-trifluoroacetyl-camphor (Camph-) has been utilized as the chiral chelating ligand to synthesize several 3d-4f Schiff-base complexes, where two chiral anions are anchored on Ln ion rendering chiral coordination sphere around the rare-earth metal center. Depending on the enantiomer of the ligand employed in the synthesis, either Delta or LAmbda stereochemistry of the Ln polyhedron is obtained. This approach allowed synthesis of several families of enantiopurs SMMs chiral at Ln such as [LMe2Ni(H2O)Ln(camph)2(CF3SO3)] or [LMe2Zn(Cl)Ln(camph)2(MeOH)], where LMe2 = bicompartmental Schiff-base ligand. In each case, reaction with the R-(+) Camph ligand results in a Lambda stereochemistry, while a Delta stereochemistry is yielded upon reaction with the S-(-) Camph ligand. However, such a stereo-selectivity is not systematic. The third anion or an ancillary ligand associated with the rare-earth metal centers appears to play an important role in controlling the stereochemistry of the coordination sphere around the rare-earth metal centers. Using the same approach, we have also successfully isolated mono-metallic chiral 4f complexes of general formulae [Ln(Camph)4]-. The study of magnetic behaviors revealed Single Molecule Magnet (SMM) behavior for several complexes containing Tb or Dy ions.
293

X-ray diffraction studies of co-ordination compounds

Mais, R. H. B. January 1965 (has links)
No description available.
294

Nouveaux complexes métallylènes du groupe 14-fer pour la préparation de nanoalliages : synthèse et caractérisation / New group 14 metallylene iron complexes for the preparation of nano-alloys : synthesis and characterization

El Ezzi, Mohammad 27 March 2015 (has links)
Ce travail porte sur la conception de nouvelles espèces divalentes du groupe 14 (germanium, étain) et sur l'étude de leurs propriétés de coordination vis-à-vis des métaux de transition et plus particulièrement le fer. Une première série de métallylènes stabilisés par coordination intramoléculaire avec des ligands N-chélatants de type amidinate a été synthétisée et caractérisée. Dans un second temps, nous avons envisagé l'utilisation d'un nouveau système O,C,O chélatant faisant intervenir des groupements arylsulfones. L'intérêt de ce ligand de type " pince " est de coupler une stabilisation cinétique grâce à l'encombrement stérique des sulfones et une stabilisation thermodynamique par coordination des oxygènes avec l'élément du groupe 14. L'effet ortho directeur des groupements sulfonyles a permis des réactions de métallation sélectives et l'obtention des premiers chloro-germylène et -stannylène à ligand arylsulfone. Une dernière méthode de stabilisation des chlorogermylènes par coordination intermoléculaire utilisant des carbènes N-hétérocycliques (NHC) comme co-ligands a été également développée. Quelques tests spécifiques de réactivité (réactions d'oxydation par une orthoquinone et réactions de complexation avec des métaux de transition) ont confirmé le caractère divalent de ces espèces. Une série de nouveaux complexes de fer à ligand germylène a été préparée. A côté de leur intérêt sur le plan fondamental, une des applications de ces complexes est de pouvoir constituer des précurseurs monosources d'alliages GeFe. En effet, leur bas degré d'oxydation (+2) ainsi que la présence de ligands labiles devrait faciliter l'accès à des nanomatériaux dans des conditions douces. / This work concerns the design of new divalent group 14 species (germanium, tin) and the study of their coordinative properties to transition metals and especially iron. A first set of intramolecularly stabilized metallylenes with N-chelating ligands such as amidinate was synthesized and characterized. In a second step, we envisaged the use of a new OCO chelating system involving arylsulfonyl groups. The advantage of this pincer-ligand is to allow a kinetic stabilization (sterically hindering sulfones) and thermodynamic stabilization (intramolecular coordination between oxygen and group element 14. Thanks to the ortho-director effect of the sulfonyl group, selective metalation reactions were performed and the first chlorogermylene and chlorostannylene containing arylsulfone substituent were isolated. In the next step, intermolecular stabilization was developed. It involves the use of N-heterocyclic carbene (NHC) as stabilizing co-ligand of metallylenes. We have prepared and characterized various NHC stabilized dichlorogermylenes. Some specific reactivity tests were carried out such as oxidation reactions in the presence of an orthoquinone and coordination reactions with transition-metals which have confirmed their specific character of divalent sites. We were able to prepare a series of variously stabilized germylene-iron complexes. Besides their interest on the fundamental level, one of the applications of these complexes is to be used as single-source precursors of GeFe nanoalloys. Indeed, their low oxidation state (+2) and the presence of labile ligands should facilitate the access of nanomaterials in the mild conditions.
295

Novel aspects of platinum-amine coordination compounds: their chemistry and anticancer application

Bouwer, Yolanda January 2008 (has links)
The aim in this thesis, was to synthesize novel platinum coordination compounds, in order to develop compounds with improved anticancer action which could lead to an improved understanding of the mechanism by which they operate and at the same time, improve synthetic methods for their products. The initial work included the development of a novel synthetic method for 1R,2R-diaminocyclohexaneoxalato-platinum(II) (oxaliplatin), by using an essentially non-aqueous solvent medium and direct ligand exchange at elevated temperatures. This was done by a study of the kinetics of the reaction in a variety of conditions; such as relative reagent concentrations and ratios as well as solvent mixtures. An effective method was developed which could be applied industrially. An international patent was taken out on this method. Various amine complexes of platinum(II) were synthesized using chloro, bromo and oxalato groups as leaving groups. The non-leaving groups were selected having certain specific characteristics in mind. Novel mononitroplatinum(IV) complexes were synthesized, mostly with oxalato leaving groups. One of these in particular, had excellent anticancer behaviour. Another trichloromononitro complex was also synthesized with very good anticancer properties. Two international patents were filed for the latter two compounds. As far as possible, all compounds were studied by spectrometric, chromatographic and thermal methods. They were also tested against 3 cancer cell lines namely cervical (Hela), Colon (HT29) and Breast (MCF7) cancer cells.
296

Advances in platinum-amine chemotherapeutic agents : their chemistry and applicationc

Jaganath, Yatish January 2009 (has links)
The research conducted in this study focussed on advancing the knowledge database of diamineplatinum complexes on two frontiers: 1) the development of novel anticancer complexes, and 2) improvements in their synthetic chemistry. Novel square-planar dichloro and oxalato platinum(II) complexes were synthesized as potential anticancer agents in accordance with a comprehensive set of factors identified as being significant in optimizing such action. The nonleaving ligands consisted of asymmetric chelating chiral diamines of the form 1- (1-R-imidazol-2yl)(R')methanamine (R representing methyl, butyl and R' methyl, phenyl). The complexes were characterized by a host of spectral, thermal and crystallographic techniques. In addition, the stabilities of the complexes were monitored in aqueous and saline solutions. Cytotoxicity screening on three cultured cancer cell lines (MCF-7, HeLa and HT29) indicated the compounds, present as their respective racemates, to have rather modest activities relative to cisplatin; with complexes having the smallest substituents, R,R' = methyl, being most active. In recognition of the limitations of traditional silver-based syntheses of oxalatoplatinum(II) complexes, innovative non-silver methods were developed using the well known cancer drug, oxaliplatin, (trans-R,R-1,2- diaminocyclohexane)oxalatoplatinum(II), as a prototype. These involved direct ligand exchange reactions of the dichloro precursor, (trans-R,R-1,2- diaminocyclohexane)dichloroplatinum(II), with tetrabutylammonium oxalate in essentially non-aqueous solvents. A 90:10 mixture of isoamyl alcohol (3-methyl- 1-butanol):water, proved to be a promising solvent, enabling the recovery of pure oxaliplatin (~98 percent) after 9 hours at 88 °C in yields of up to 86 percent. In light of the perceived unique mode of anticancer action available to mononitroplatinum(IV) complexes (i.e. their STAT3-binding potential), octahedral diamineoxalatoplatinum(IV) complexes containing axially-coordinated nitro and halo co-ligands were synthesized and extensively characterized. Electrochemical studies revealed trends in reduction potential which could be correlated to structural / chemical traits of the coordinated diamine and axial ligands. The similarities of the determined cytotoxicities of the platinum(IV) compounds and their respective platinum(II) analogues, implicated reduction as a means of activation of the platinum(IV) complexes.
297

Thiatriazines: Building Blocks Towards Molecular Materials

Kleisath, Elizabeth January 2016 (has links)
Post-functionalization of 3,5-bis(2-pyridyl)-4-hydro-1,2,4,6-thiatriazine (Py2TTAH) and its synthetic precursors have been explored through alkylation, arylation, and coordination. While alkylation was initially pursued at the central nitrogen atom of Py2TTAH, functionalization instead occurred on the sulfur atom. Consequently, the proclivity of the sulfur towards alkylation and arylation was studied. Neutral 3,5-bis(2-pyridyl)-S-methyl-1,2,4,6-thiatriazine (S-Me-Py2TTA) and 3,5-bis(2-pyridyl)-S-ethyl-1,2,4,6-thiatriazine were achieved via either anionic or cationic intermediates, and all isolable species were fully characterized. In addition, an aromatic derivative, 3,5-bis(2-pyridyl)-S-phenyl-1,2,4,6-thiatriazine was obtained through reactions using hypervalent iodide as an electrophile. Functionalization of Py2TTAH and S-Me-Py2TTA was also explored through coordination with iron. The synthesis and crystal structures of two different iron complexes are described. The incorporation of boron with Py2TTAH and its precursor, N-2-pyridylimidoyl-2-pyridylamidine was also considered. Both compounds afforded the same boratriazine ring. Overall, this thesis describes the groundwork for future functionalization of the Py2TTA framework, and its potential for molecular materials applications.
298

Federalism and the institutional dynamics of intergovernmental spatial policy coordination in Canada

Webb, Brian Norman January 2011 (has links)
This thesis discusses the governmental institutional dynamics that structure the formulation and coordination of spatial policy within the federal Canadian intergovernmental system and presents methods to improve it. The research utilises the three traditions of new institutionalism - historical, rational choice and sociological - to develop a crosscutting assessment of intergovernmental spatial policy coordination. An embedded case study approach is then used to discuss intergovernmental spatial policy coordination between the governments of Canada, British Columbia, Alberta and Saskatchewan. Research findings highlight the uniqueness of the institutional environments that exist within each government, and to a lesser extent each department, which structure policymakers’ understandings of intergovernmental spatial policy coordination. Policymakers demonstrate a distinct awareness of spatial issues, but they are often constrained in their ability formally to articulate this in the development of public policy, particularly in relation to intergovernmental interactions. The decentralised federal nature of Canada is shown to be a highly influential reason for this, with issues of history, equity, politics and strong regional government cultures playing important roles in impeding intergovernmental spatial policy coordination. The thesis explores these constraints, discussing how both formal and informal institutional structures interact to discourage the use of spatial policy, and discusses the ways in which intergovernmental spatial policy coordination could be enhanced in the specific context of Canada. The institutional framework developed in this research is shown to be a useful method for conceptualising the competing federal principles of unity and diversity in the study of intergovernmental spatial policy coordination. Ultimately this thesis argues that while intergovernmental spatial policy coordination is poorly developed in Canada, policymaker awareness of spatial issues influences the decision-making processes employed to develop and coordinate public policy.
299

Coordination of primary health care

Foskett-Tharby, Rachel Christine January 2014 (has links)
Background: Improving coordination of care is a major challenge for health systems internationally. Tools are required to evaluate alternative approaches to improve coordination from the patient perspective. This study aimed to develop and validate a new measure of coordination for use in a primary care setting. Methods: Four methods were used. Firstly, a concept analysis was undertaken to identify the essential attributes of coordination drawing upon literature from health and organisational studies and to establish its boundaries with related concepts such as continuity of care, integration and patient centred care. Secondly, existing measures of coordination were reviewed to assess the extent to which item content reflected the definition arising from the concept analysis and to appraise psychometric properties. Thirdly, a new instrument, the Care Coordination Questionnaire (CCQ), was developed utilising items from existing questionnaires and others developed following focus groups with 30 patients. Ten cognitive interviews were used to evaluate the items generated. Finally, the CCQ was administered in a cross sectional survey to 980 patients. Item and model analyses were performed. Test-retest reliability was evaluated through a second administration of the CCQ after two weeks. Concurrent validity was evaluated through correlation with the Client Perceptions of Coordination Questionnaire (CPCQ). Construct validity was evaluated through correlation with responses to a global coordination item and a satisfaction scale and the testing of two a prior hypotheses: i) coordination scores would decrease with increasing numbers of providers and ii) coordination scores would decrease with increasing numbers of long-term conditions. Results: The concept analysis suggested that coordination should be considered as a process for the organisation of patient care characterised by: purposeful activity, information exchange, knowledge of roles and responsibilities, and responsiveness to change. The systematic review identified 5 existing measures of coordination and a further 10 measures which incorporated a coordination subscale. Only one demonstrated conceptual coverage but had poor psychometric properties. A new instrument was therefore developed and tested as described above. 299 completed surveys were returned. Respondents were predominantly elderly and of white ethnicity; approximately half were female. Five items were deleted following item analyses. Model analysis suggested a four factor two-level model of coordination comprising of 18 items. This correlated well with the CPCQ, the global coordination item and satisfaction scale. The a priori hypotheses were upheld. Retest reliability was acceptable at the patient group level. Conclusions: The CCQ has demonstrated good psychometric characteristics in terms of item responses, reliability and construct validity. Further exploration of these properties is required in a larger, more diverse sample before it can be recommended for widespread use, but it shows potential utility in the evaluation of different approaches to coordinating care.
300

Synthesis and Design of Thiophene Materials: Effects of Ring Fusion and Metal Coordination

Konkol, Kristine Louise January 2019 (has links)
Conjugated organic materials comprise a field of materials chemistry focused on the development of semiconducting organic plastics, popular applications of which are plastic solar cells and display technologies. One of the reasons these materials have gained so much attention is that their optical and electronic properties can be tuned through engineering at the molecular level. Thiophene, an aromatic heterocycle, is a popular building block in the synthesis of many conjugated materials, prized for both the ease in which it can be synthetically functionalized and its ability to form highly conductive and low band gap materials. The Rasmussen group has previously reported on the generation of two classes of materials, the inorganic metal thiophenedithiolenes and the fused-ring heterocycle unit thieno[3,4-b]pyrazine (TP), both of which have applications in conducting materials. In an effort to expand upon the applicability and versatility of these materials, a series of interconnected projects were performed to further tune their optical, electronic, and physical (e.g. solubility) properties. This involved synthetic molecular design, including judicious consideration of structure-function relationships, and characterization of the resulting materials. Highlights include a sterics vs. electronics consideration of the catalyzed hydrodebromination of the molecular building-block 2,3,5-tribromothiophene, variation of the coordinating metal in thiophenedithiolenes to tune the optics and electronics, and characterization of the effects of ring-fusion on TP-based terthienyl homopolymers. Additionally, a new application of the TP monomer was found, whereby it was successfully incorporated as a bridging ligand into a multi-metallic Ru(II) supramolecular assembly, which demonstrated good metal-metal communication.

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