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    Structural studies of organic crystals of pharmaceutical relevance. Correlation of crystal structure analysis with recognised non-bonded structural motifs in the organic solid state

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    Thesis-Abstract,table of contents.pdf (338.2Kb)
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    Thesis introduction-chapter one.pdf (483.8Kb)
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    Thesis-experimental-chapter 2.pdf (197.5Kb)
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    Chalcones-chapter 3.pdf (1.147Mb)
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    cryptolepines -chapter 4.pdf (1.108Mb)
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    Biguanides-chapter 5.pdf (1.088Mb)
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    xanthines-chapter 6.pdf (1.503Mb)
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    CONCLUSION -chapter 7.pdf (47.30Kb)
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    references.pdf (159.0Kb)
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    Thesis-Appendix-A,B and C.pdf (239.4Kb)
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    INFRA_RED-Appendix D.pdf (981.8Kb)
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    PXRD-Appendix E.pdf (1.071Mb)
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    Raman-Appendix F.pdf (776.0Kb)
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    Mass Spec-Appendix G.pdf (302.6Kb)
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    NMR-Appendix H.pdf (2.749Mb)
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    structures.pdf (28.45Kb)
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    Publication date
    2010-10-07T11:36:24Z
    Author
    Essandoh, Ernest
    Supervisor
    Scowen, Ian J.
    Edwards, Howell G.M.
    Keyword
    Single crystal structure
    ; Structural motifs
    ; Pharmaceutical solids
    ; Polymorph
    ; Physico-chemical stability
    ; Chalcones
    ; Cryptolepines
    ; Biguanides
    ; Xanthines
    ; Crystallization studies
    Rights
    Creative Commons License
    The University of Bradford theses are licenced under a Creative Commons Licence.
    Institution
    University of Bradford
    Department
    School of Pharmacy
    Awarded
    2009
    
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    Abstract
    Pharmaceutical solids tend to exist in different physical forms termed as polymorphs. Issues about pharmaceutical systems are mainly concerned with the active ingredient's physico-chemical stability and bioavailability. The main aim of this study is to investigate the non-bonded interactions in pharmaceutical solids that govern the physical pharmaceutics performance of such materials and through the use of structural techniques and correlation of these results with crystal structural database to establish the presence of physical motifs in selected systems. Structural motifs were identified by the use of single crystal and crystal packing analysis on diverse range of pharma-relevant materials including chalcones, cryptolepines, biguanides and xanthines. These selected systems were validated using functional group and molecular analysis and correlating them to the Cambridge Structural Database. Crystallization studies are done on these selected systems as well as exploiting those using synthetic analogues. A total of 51 crystal structures were investigated including 16 new structure determinations. Addition synthesis of new xanthines to investigate novel intermolecular patterns was also undertaken. The understanding and exploitation of intermolecular interactions involving hydrogen bonds and coordination complexation during packing can be used in the design and synthesis of solid state molecular structures with desired physical and chemical properties.
    URI
    http://hdl.handle.net/10454/4444
    Type
    Thesis
    Qualification name
    PhD
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      Organisation, practice and experiences of mouth hygiene in stroke unit care: a mixed methods study.

      Horne, Maria; McCracken, G.; Walls, A.; Tyrrell, P.J.; Smith, C.J. (2015-03)
      Aims and objectives To (1) investigate the organisation, provision and practice of oral care in typical UK stroke units; (2) explore stroke survivors', carers' and healthcare professionals' experiences and perceptions about the barriers and facilitators to receiving and undertaking oral care in stroke units. Background Cerebrovascular disease and oral health are major global health concerns. Little is known about the provision, challenges and practice of oral care in the stroke unit setting, and there are currently no evidence-based practice guidelines. Design Cross-sectional survey of 11 stroke units across Greater Manchester and descriptive qualitative study using focus groups and semi-structured interviews. Methods A self-report questionnaire was used to survey 11 stroke units in Greater Manchester. Data were then collected through two focus groups (n = 10) with healthcare professionals and five semi-structured interviews with stroke survivors and carers. Focus group and interview data were recorded, transcribed verbatim and analysed using framework approach. Results Eleven stroke units in Greater Manchester responded to the survey. Stroke survivors and carers identified a lack of oral care practice and enablement by healthcare professionals. Healthcare professionals identified a lack of formal training to conduct oral care for stroke patients, inconsistency in the delivery of oral care and no set protocols or use of formal oral assessment tools. Conclusion Oral care post-stroke could be improved by increasing healthcare professionals' awareness, understanding and knowledge of the potential health benefits of oral care post-stroke. Further research is required to develop and evaluate the provision of oral care in stroke care to inform evidence-based education and practice.
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