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Britt, Michelle L. "Culture and identity : the academic setting in Philip Roth's The Human Stain and Francine Prose's Blue angel /." Electronic version (PDF), 2003. http://dl.uncw.edu/etd/2003/brittm/michellebritt.pdf.
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McKnight, Nathan L. "Strain and strain rate mechanotransduction in human vascular smooth muscle cells /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2002. http://wwwlib.umi.com/cr/ucsd/fullcit?p3076345.
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Mitchell, Judy Anne. "Human metapneumovirus: Investigation of epidemiology strain diversity and human immune response." Thesis, Open University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486510.
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Human metapneumovirus (hMPV) is a newly described respiratory virus belonging to the Paramyxoviridae family, first identified in respiratory samples of ·children with acute respiratory tract infection (ARTI). Since its discovery hMPV has been associated with ARTI worldwide, however, important questions remain as to the contribution ofhMPV to respiratory illness, and its impact on public health. Extensive surveillance ofhMPV within different populations of the United Kingdom (UK) demonstrates it is an important cause of ART! in the elderly, and influenza like illness ~ (ILl) in people of all ages in the community. Furthermore it is a frequent cause of hospitalisation in young children. Recombinant baculovirus expressed hMPV nucleocapsid protein (N) proved to be a useful source of antigen for the development of an hMPV specific ELISA. Analysis of age stratified sera from the UK indicates that a majority of children are infected by the age of 6 years with primary infections occurring throughout infancy. Virtually all adults have detectable levels ofhMPV antibody; however, reinfection with hMPV is common, raising questions concerning acquisition and duration of immunity. Sequence analysis of the attachment glycoprotein (0), shows a high degree of nucleotide and amino acid variation and extensive glycosylation. Frequent nucleotide insertions or deletions result in frame shift mutations which can drastically alter the appearance of the protein and often results in premature termination. Antibody recognition of hMPV 0 is likely to be highly strain specific and dependent on the extent of glycosylation, suggesting an involvement of 0 in immune evasion. Phylogenetic analysis of hMPV 0 gene sequence shows that whilst a large degree of variation exists within this gene, strains circulating within the UK are genetically similar to strains circulating elsewhere in the world, and similar strains circulate throughout different years and populations within the UK.
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Akter, Parvis. "Transcript mapping in human cytomegalovirus strain AD169." Thesis, University of Glasgow, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394827.
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Parise, Maria Cecilia Isatto [UNIFESP]. "As colorações da alma na análise da pessoa humana segundo Edith Stein." Universidade Federal de São Paulo (UNIFESP), 2014. http://repositorio.unifesp.br/handle/11600/39261.
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Neste trabalho, investigamos o conceito de alma e sua importância para a compreensão da pessoa humana segundo Edith Stein. Mostraremos, a partir de O problema da empatia (1916), A estrutura da pessoa humana (1932) e Ciência da cruz (1942), três obras de momentos distintos da vida da autora, um paralelo entre o modo como ela aprofunda a análise fenomenológica da alma, mantendo-se sempre vinculada ao método aprendido de Edmund Husserl, e sua vivência existencial de relação pessoal com Deus. Constatamos que em sua tese de 1916, O problema da empatia, Edith Stein já havia elaborado uma concepção estrutural da alma que passa a ser ampliada e aprofundada nas demais obras, sem sofrer grandes alterações. Desse modo, a análise fenomenológica do conceito de alma empreendida por Edith Stein nessas obras nos permite apontar para uma notável coerência e continuidade de seu pensamento nos diferentes períodos de sua vida, assim como sua estreita vinculação ao método fenomenológico de Edmund Husserl.
This study addresses the concept of the soul according to Edith Stein as a foundation for understanding her notion of human person. We will show through three studies published by the author at distinctly different moments: Zum Problem der Einfühlung (1916), Der Aufbau der menschlichen Person (1932) and Kreuzeswissenschaft (1942)], a parallel between the way she delves into the phenomenological analysis of the soul, very much influenced by the phenomenological method taught by Edmund Husserl, and her own existential experience in her intimate relation with God. We found that in her 1916 thesis, On the problem of Empathy, Edith Stein had already elaborated a structural concept of soul which, while enhanced and amplified, remained largely unaltered throughout her subsequent works. Thus, the phenomenological analysis of the concept of soul manifested in these three works, allows us to observe a profound coherence and continuity of thought throughout an significant period of her life, as well as her unswerving adherence to Edmund Husserl’s phenomenological method.
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Vijayakumar, Vinod. "Stress/strain environments in healing human tibial fractures." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275202.
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Wilkinson, Gavin William Grahame. "Regulation of human cytomegalovirus strain AD169 gene expression." Thesis, University of Warwick, 1987. http://wrap.warwick.ac.uk/2540/.
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Human cytomegalovirus (HCMV) strain AD169 encodes a single abundant 1.95kb immediate early (IE) mRNA and a single abundant 2.7kb early RNA. The major IE gene (0.756-0.745 map units) was shown in nuclease protection experiments to encode a spliced molecule of 1,736 nucleotides (excluding the poly(A) tail) consisting of four exons of 121, 88, 185 and 1,342 nucleotides. Three introns of 827, 114 and 170 nucleotides were located near the 5' end of the gene. The structural analysis of the major IE gene enabled the amino acid sequence of the major IE polypeptide to be deduced from the DNA sequence. The major early gene, which is contained in both copies of the HCMV long repeat, was found not to be spliced. A translation product of the 2.7kb early RNA has yet to be identified. Reporter genes were used in transient DNA transfection experiments to monitor expression from HCMV and other viral promoters. HCMV infections trans-activated expression from the transfected SV40 early, Rous Sarcoma virus, HSV-1 thymidine kinase (TK), the HCMV major IE and the HCMV major early promoters. Expression from both the HCMV IE and the HSV-1 TK promoters was stimulated much more gradually by HCMV than by HSV-1 infections. Experiments performed using u.v.-irradiated virus and inhibitors of HCMV replication indicated that the transfected IE promoter was stimulated primarily by a de novo synthesised HCMV-encoded gene product(s). When the concentration of the plasmids IEPlcatIEterm and AccHincat transfected into cells was lowered sufficiently, HCMV infection was observed to repress expression from the transfected IE promoter. A sequence in the HCMV major IE gene between -299 and + 69 apparently contains a cis-acting signal which responds to an HCMV-induced repressor. Competitive co-transfection experiments indicated that an HCMV-induced repressor of IE transcription interacts with at least three distinct regions within the IE promoter.
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Potkalitsky, Nicolas J. "Refracted Realism and the Ethical Dominant in Contemporary American Fiction." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1563283222402333.
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Carneiro, Suzana Filizola Brasiliense. "A formação humana em contexto de violência: uma compreensão clínica a partir da Fenomenologia de Edith Stein." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/47/47133/tde-16082016-115100/.
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Este estudo, baseado na Fenomenologia de Edith Stein, teve por objetivo compreender as vivências fundamentais de pessoas que vivem em um contexto marcado pela violência, bem como investigar as repercussões dessas vivências em seu processo formativo. A pesquisa foi realizada no bairro do Uruguai, em Salvador (BA), região conhecida como Alagados. A apreensão das vivências ocorreu pelos registros de um diário de bordo e por 15 entrevistas abertas com os moradores. A análise foi realizada em dois momentos. No primeiro, selecionamos 4 entrevistas (2 homens e 2 mulheres) e realizamos uma análise individual dos participantes, tomando como referência as dimensões constitutivas da pessoa segundo Edith Stein (vivências psicofísicas, espirituais e interpessoais, aspectos éticos e religiosos). No segundo, selecionamos, das 15 entrevistas, vivências significativas para os participantes do ponto de vista formativo e as agrupamos em 8 vivências fundamentais: 1) vivência do improviso (da urgência da vida); 2) vivência da morte; 3) vivência da chaga; 4) vivência de violência; 5) vivência da solidariedade; 6) vivência da periferia; 7) vivência da maternidade e 8) vivência da religiosidade. A análise individual dos 4 participantes possibilitou identificar um movimento formativo comum, caracterizado por vivências psicofísicas de forte intensidade que culminaram com a experiência do limite pessoal a partir de uma situação de morte eminente. Esta última, por sua vez, motivou a vivência da escuta de si e do reconhecimento de um apelo interior de realização (núcleo pessoal), dando origem ao propósito de dar novo rumo à própria vida. Entretanto, a concretização desse propósito não se deu de modo automático, mas foi marcado por momentos de luta interior entre essa decisão (própria da dimensão espiritual) e o movimento psíquico reativo de busca de bem-estar e segurança, que apontava para a permanência da pessoa no status quo. O último momento reconhecido foi a decisão livre de seguir o apelo sentido, dando início a um processo de transformação da pessoa e do contexto em que ela se insere. Constatamos também, nesse processo, que não basta o reconhecimento do apelo do núcleo pessoal para que a pessoa assuma a direção da própria vida, mas que ela necessita de uma quantidade mínima de força vital para realizar-se nesta direção. Nesse sentido, identificamos 5 fontes de força espiritual para os participantes, que os auxiliam nesse processo, o que pode servir de orientação para intervenções futuras: 1) a história do bairro; 2) a arte (dança, música, filmes); 3) a vivência da solidariedade; 4) a própria história de vida da pessoa (testemunho) e 5) a religiosidade. Também levantamos como orientação para futuras intervenções a necessidade de um trabalho que auxilie os moradores na expressão de suas vivências e no desenvolvimento da dimensão espiritual (intelecto e vontade). Finalmente, pudemos constatar a beleza e a força da pessoa humana, as quais nenhum contexto de violência é capaz de anularThis study, based on Edith Steins Phenomenology, has aimed to understand the fundamental lived experiences of people living in a context of violence, as well as to inquire into the repercussions of these lived experiences to their formative process. The research was conducted in Salvador, Bahia, in the Uruguai neighborhood, an area known as Alagados. The gathering of the lived experiences was done by means of a daily journal and 15 open ended interviews with inhabitants of the area. The analysis was executed in two moments. At first, we selected four interviews (2 men and 2 women) and did an individual analysis of the participants, in the light of the constitutive dimensions of the person according to Edith Stein (psycho-physical, spiritual and interpersonal lived experiences, religious and ethical aspects). For the second moment we selected, from among the 15 interviews, meaningful lived experiences for the participants from a formative standpoint, and grouped them according to 8 fundamental lived experiences: 1) the lived experience of improvisation (the urgency of life); 2) the lived experience of death; 3) the lived experience of woundedness; 4) the lived experience of violence; 5) the lived experience of solidarity; 6) the lived experience of the periphery; 7) the lived experience of maternity; and 8) the lived experience of religiosity. The individual analysis of the 4 participants allowed us to identify a common formative movement, featuring high intensity psycho-physical lived experiences which culminated in the experience of personal limits in the face of a situation of imminent death. This latter experience, in its turn, led to the experience of the listening of the self and the recognition of an interior appeal towards fulfillment (the personal nucleus), originating the purpose of giving life a new direction. However, this purposes achievement did not take place automatically, but was characterized by moments of inner struggle between this decision (proper to the spiritual dimension) and the reactive psychological movement of the search of welfare and security, which pointed towards keeping the person in her status quo. The last recognized moment was the free decision to follow the sensed appeal, setting off a process of transformation of the person and her context. We observed, also, during this process, that the recognition of the personal nucleuss appeal is not enough for the person to take over her lifes direction, but that she needs a minimal amount of vital force in order to be fulfilled in this direction. Accordingly, we have identified 5 sources of the spiritual vital force that will support the participants in this process, which may serve as signposts for future interventions: 1) the neighborhoods history; 2) art (dance, music, films); 3) the experience of solidarity; 4) the persons own life history (witness); and 5) religiosity. We have also discovered, as orientation points for future interventions, the need of work that allows the inhabitants to express their lived experiences and to develop their spiritual dimension (intellect and will). Finally, we have been able to witness the beauty and the strength of the human person, both of which no violent context has the power to dispel
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Voorhies, Katherine Desiree. "Static and Dynamic Stress/Strain Properties for Human and Porcine Eyes." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/31867.
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Every year, more than 2.4 million eye injuries occur in the United States, with over 30,000 of those injured left blind in at least one eye as a result. Computer modeling is one of the most versatile ways to study ocular trauma, however, existing models lack accurate stress and strain properties for ocular globe rupture. A pressure system was built to examine static and dynamic globe rupture pressures for healthy postmortem human and porcine (pig) eyes. Maximum rupture stress for the quasi-static tests was found to be 11.17MPa for human tissue and 12.08MPa for porcine tissue, whereas stress for the dynamic tests was found to be 30.18MPa for human tissue and 26.01MPa for porcine tissue. Maximum rupture stress results correlate well with static material properties used in published research (9.4MPa), and dynamic properties of 23MPa found in published research. Healthy postmortem human eyes were ruptured statically and dynamically to determine the relationship between stress and strain for the ocular globe under intraocular pressure loading. Stress-strain relationships were investigated and values for the elastic modulus were found to be slightly lower than that previously published. This research shows that it is important to differentiate between tissue type, and static versus dynamic failure properties before drawing conclusions from computer models and other published research. Now that rupture can be accurately determined, safety systems designed to protect eyesight in automotive, sports, and military applications can also be applied to protect the quality of life for humans in these applications.Master of Science
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Jones, Eleanor. "Investigation of the effects of mechanical strain in human tenocytes." Thesis, University of East Anglia, 2012. https://ueaeprints.uea.ac.uk/42329/.
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Tendinopathies are a range of diseases characterised by pain and insidious degeneration. Although poorly understood, onset is often associated with physical activity. Metalloproteinases are regulated differentially in tendinopathy causing disruptions in extracellular matrix (ECM) homeostasis. An increase in the anti-inflammatory cytokine TGFβ has also been documented. This project aims to investigate the effect of cyclic tensile strain loading and TGFβ stimulation on protease and ECM protein expression by human tenocytes and begin to characterise the pathway of mechanotransduction. Human tenocytes were seeded at 1.5x106 cells/ml into collagen gels (rat tail type I, 1mg/ml) and stretched using a sinusoidal waveform of 0-5% at 1Hz using the Flexcell FX4000T™ system. Cultures were treated with or without 1ng/ml TGFβ1 or inhibitors of TGFβRI, metalloproteinases, RGD, Mannose-6-phosphate, integrin β1 and a thrombospondin as appropriate. qRT-PCR and a cell based luciferase assay were used to assess RNA and TGFβ activity respectively. The prolonged application of 5% cyclic mechanical strain in a 3D culture system induced an anabolic response in protease and matrix genes. In most genes changes in gene expression with loading was mirrored with TGFβ stimulation. We also demonstrated that the inhibition of the TGFβRI abrogated the strain induced changes in mRNA. TGFβ activity was increased with 48 hours mechanical strain although there was no increase in mRNA or total TGFβ. This indicates that TGFβ activation plays an important role in the mechanoregulation of gene expression. Inhibition of potential mechanisms of TGFβ activation including; serine protease or metalloproteinase activity, integrin or thrombospondin interaction with latent TGFβ showed no effect upon TGFβ activation or gene regulation with strain. Therefore strain mediated TGFβ activation may occur via a novel mechanism. By understanding mechanotransduction, we may be able to determine whether dysregulation of this system is involved in the development of tendinopathy.
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Murrell, Isa. "Developing a Human Cytomegalovirus strain for better in vitro research." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/70849/.
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Investigations into Human Cytomegalovirus (HCMV) pathogenesis should be based on strains that closely reflect the causative agent of disease, however HCMV invariably mutates in vitro, generating phenotypically distinct laboratory-adapted strains. In particular, mutations are selected in the HCMV genome UL128 locus (UL128L) that encodes sub-units of a virion envelope pentameric complex that impedes virus propagation in fibroblasts (the cell type most commonly used in vitro), but is required for infection of several naturally targeted cell-types (e.g. epithelial, endothelial, and myeloid cells). Addressing this issue, the genome of wildtype HCMV strain Merlin was cloned as a stable bacterial artificial chromosome (BAC), however similarly to clinical isolates, viruses reconstituted from the Merlin-BAC grow poorly and are prone to de novo mutation in cell culture. Direct comparison to viruses from the Merlin-BAC revealed that viruses from the BACcloned versions of strains TR (TR-BAC), TB40E (TB40-BAC4) and VR1814 (FIX-BAC) could be propagated more efficiently in fibroblasts, despite containing intact UL128L ORFs. Unique nucleotide variations identified in TB40-BAC4 and FIX-BAC UL128L ORFs were transferred into the Merlin-BAC, generating variants that produced greater titres of cell-free virus following reconstitution. Virions from these novel Merlin variants displayed reduced pentameric complex content, but remained able to infect epithelial cells, albeit with slightly compromised efficiency. The greater fitness of viruses from these novel Merlin-BAC variants alleviated the selective pressures for the selection of de novo UL128L mutations in fibroblasts. The Merlin virion proteome was determined, with up to 30 novel components identified to provide a more comprehensive picture of wildtype HCMV virion composition. Comparison of virions from several Merlin variants demonstrated that varying pentameric complex content impacted the incorporation of other components, however virions from the novel Merlin variants produced in this work closely matched those from the parental Merlin variant containing wildtype UL128L ORFs. Thus, the novel Merlin-BAC variants produced in this work represent valuable reagents for future HCMV research.
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Tamimi, Ehab A., Jeffrey D. Pyne, Dominic K. Muli, Katelyn F. Axman, Stephen J. Howerton, Matthew R. Davis, Christopher A. Girkin, and Geest Jonathan P. Vande. "Racioethnic Differences in Human Posterior Scleral and Optic Nerve Stump Deformation." ASSOC RESEARCH VISION OPHTHALMOLOGY INC, 2017. http://hdl.handle.net/10150/626003.
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PURPOSE. The purpose of this study was to quantify the biomechanical response of human posterior ocular tissues from donors of various racioethnic groups to better understand how differences in these properties may play a role in the racioethnic health disparities known to exist in glaucoma. METHODS. Sequential digital image correlation (S-DIC) was used to measure the pressure-induced surface deformations of 23 normal human posterior poles from three racioethnic groups: African descent (AD), European descent (ED), and Hispanic ethnicity (HIS). Regional in-plane principal strains were compared across three zones: the optic nerve stump (ONS), the peripapillary (PP) sclera, and non-PP sclera. RESULTS. The PP scleral tensile strains were found to be lower for ED eyes compared with AD and HIS eyes at 15 mm Hg (P = 0.024 and 0.039, respectively). The mean compressive strains were significantly higher for AD eyes compared with ED eyes at 15 mm Hg (P = 0.018). We also found that the relationship between tensile strain and pressure was significant for those of ED and HIS eyes (P < 0.001 and P = 0.004, respectively), whereas it was not significant for those of AD (P = 0.392). CONCLUSIONS. Our results suggest that, assuming glaucomatous nerve loss is caused by mechanical strains in the vicinity of the optic nerve head, the mechanism of increased glaucoma prevalence may be different in those of AD versus HIS. Our ONS strain analysis also suggested that it may be important to account for ONS geometry and material properties in future scleral biomechanical analysis.
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Campbell, Katherine Gillian. "An investigation into strain within the patellar tendon." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/12050/.
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Tendon injuries have, for many years, frustrated clinicians and patients alike due to their longevity and resistance to therapy. In recent years there has been good response in the extensor tendons of the lower limb to an intense painful eccentric exercise protocol. As yet there is no established reason known why a tendon should develop degeneration within its structure or why it should respond to the eccentric exercises. We do however know that, like bone, tendons are biologically active and rapidly adapt to the mechanical environment to which they are exposed. Recent investigations have revealed that within a tendon such as the Achilles or the patellar tendon there may be regions that experience different strains to the rest of the tendon. Much of this work has been in vitro and an ultimate goal would be the development of a non-invasive method by which intra-tendinous strain might be measured. The basis of this thesis is the validation of an existing grey-scale speckle pattern matching software programme developed for tracking motion through serial ultrasound images. Through in vitro and in vivo work we have developed its use for tracking the unique type of speckle found in tendons. By verifying, in vitro, that the displacements tracked in phantoms and tendons alike are representative of reality we provide confidence in the use of an exciting tool for measuring tendon motion in vivo. Furthermore, we have established the method by which the tracking can be adapted to accurately represent tendon strain in vitro which again provides assurance for its reliability when applied to examine tendon strain in vivo. The methods of data collection and analysis developed in this study provide the foundations for an exciting avenue of research into tendon biomechanics.
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Marecki, Andrew T. (Andrew Thomas). "Skin strain analysis software for the study of human skin deformation." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/74986.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 58).
Skin strain studies have never been conducted in a precise and automated fashion. Previous in vivo strain investigations have been labor intensive and the data resolution was extremely limited such that their results were largely qualitative. There is a need for a better system to collect, compute, and output strain measurements of the skin in vivo for the purpose of designing better mechanical interfaces with the body. Interfaces that have the same strain behavior as human skin can minimize shear forces and discomfort for the user. One particular application is improving the design of prosthetic liners for amputees, creating a second skin sleeve that provides support without hindering movement. A custom approach offering high resolution marker density, automatic point tracking and correspondences, and computational transparency is presented in this thesis. The entire computational toolbox is presented, which takes in high resolution digital photographs, tracks points on the surface of the body, corresponds points between body poses, computes a series of strain measures, and graphically displays these data. The results of studies of a full bodied human knee and a transtibial amputee's residual limb are presented here as well.
by Andrew T. Marecki.
S.M.
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Sayeur, Mathieu. "Mechanical Modeling of Human Platelets Membrane." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32876.
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In an effort to help understand the mechanical properties of human platelets, their deformations were measured using micropipette experiments over an aspiration pressure range of 1-5 cmH2O, in steps of 1 cmH2O. The experiments confirmed the previously reported linear relationship between deformation and pressure. The experimental results were used to determine the material constants of a thin-axisymmetric shell model based on a strain-energy constitutive relation to describe the platelet deformations under aspiration. The model was successful in capturing the experimental deformations. It also suggested that the mechanical properties of human platelets are not significantly influenced by their volumes, but do vary depending on the platelets’ undeformed shape ratios. In addition, the model suggested that platelet membrane ruptures due to micropipette aspiration may be strain-related. The limitations of the experimental methods arising from direct contact with reactive cells such as platelets are highlighted, prompting the need for developing new methods which will not require the use of inhibition agents that alter the platelets’ mechanical properties.
Afin d’approfondir les connaissances des propriétés mécaniques des plaquettes humaines, leurs déformations ont été mesurées lors d’expériences avec des micropipettes pour des pressions d’aspiration de 1-5 cmH2O, par intervalles de 1 cmH2O. Les expériences ont confirmé la relation linéaire entre les déformations et la pression d’aspiration telle que précédemment publié. Les données expérimentales ont été utilisées pour déterminer les constantes matérielles d’un modèle de membrane mince axisymétrique basé sur une loi de comportement caractérisant l’énergie de déformation. Le modèle simule bien les déformations des plaquettes sous aspiration; il suggère également que les propriétés mécaniques des plaquettes humaines ne sont pas influencées significativement leur volume, mais varient en fonction de leurs formes avant déformation. De plus, le modèle suggère que les ruptures de la membrane des plaquettes sous aspiration seraient reliées aux déformations. Les limites des méthodes expérimentales utilisées, du fait du contact direct avec des cellules aussi réactives que les plaquettes sont soulignées, et mettent l’emphase sur le besoin de mettre au point de nouvelles méthodes ne requérant pas d’agents d’inhibitions qui altèrent les propriétés mécaniques des plaquettes.
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Mok, Yu-Keung. "Studies on the DNA binding domain human papillomavirus strain 16 E2 protein." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264157.
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Berns, Madalyn S. (Madalyn Sarah). "Enhancing human metabolic economy in stair climbing via an elastic crutch mechanism." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68936.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 77-79).
Crutching provides a significant increase in mobility for those with limited walking ability. While level ground walking with crutches has been studied in many different forms, stair climbing is a more energetically taxing activity and the upper arm and shoulder strength required is not always available in weaker or severely injured patients. We posit that the introduction of parallel springs spanning the elbow joint will improve the crutching experience by helping patients attain a metabolic reduction compared to unassisted locomotion. Here, we present a foundation for achieving metabolic reduction with joint-spanning elastic elements. Our approach includes three parts. First, we present an augmented crutch design with an elbow spring that can be modified with different stiffnesses. Second, we put forth a clinical testing protocol in which we measure metabolic economy via the pulmonary gas exchange technique (Vo2avg). Simultaneously recording electromyographic (EMG) signals from the primary active muscles provides a neuromuscular interpretation of the crutching activity not captured by the black-box metabolic techniques. We complete the picture by modeling the energetics of the effective elbow muscle by incorporating empirical measurements of maximum angular velocity achieved under a range of isotonic conditions. The metabolic data exhibits trends consistent with our hypothesis of metabolic reduction; although, more subjects are needed to confirm these results. All subjects reported a feeling of augmentation at the optimal stiffness condition. An analysis of the EMG results show a clear transition in muscle usage patterns from a triceps only power stroke to a combined usage of both triceps and biceps. Where the triceps are maximally active during the non-augmented state, as stiffness increases the biceps become more active and the total activation level drops, suggesting the this shift is at least partially responsible for the observed metabolic reduction. While the model correctly predicts the relative shape of the observed curve, the optimal stiffness predictions are higher than their empirical equivalents. This is most likely due to the extra help the triceps muscles received from active stabilization and power muscles not considered in the model. With a more complete muscular picture one could begin to construct an accurate method of prediction and tuning of optimal stiffness.
by Madalyn S. Berns.
S.M.
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Lautridou, Jacky. "Determination of inherited or acquired factors involved in decompression sickness : creation of a DCS resistant rat strain." Thesis, Brest, 2017. http://www.theses.fr/2017BRES0135.
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L’Accident de Décompression présente un risque majeur pour les plongeurs. Il est admis que la formation de bulles circulantes est à l’origine de l’ADD. Cependant, une forte variabilité inter individuelle existe entre plongeurs, avec une faible corrélation entre bulles et symptômes de l’ADD. Plusieurs mécanismes physiologiques ont été liés à l’ADD, mais aucun d’entre eux ne semble déterminant dans la mise en place de la pathologie. Dans ce contexte, des techniques issues de la médecine de précision pourraient apporter de nouveaux éléments de compréhension.Durant cette thèse, nous avons effectué des études protéomiques afin d’étudier les possibles changements du protéome plasmatique de rats et de plongeurs suite à une plongée avec ou sans ADD, dans le but de trouver de potentiels biomarqueurs de développement précoce de l’ADD. Nous avons de plus mis en évidence une potentielle implication de processus inflammatoires dans la mise en place des symptômes de l’ADD. Un protocole de sélection a ensuite été utilisé dans le but de créer une nouvelle souche de rats résistante à l’ADD. Une résistance à l’ADD est apparue en l’espace d’une génération chez les femelles, deux chez les mâles. Une caractérisation physiologique de la souche résistante a montré une potentielle implication d’une région spécifique du chromosome X, ainsi que des modifications du fonctionnement du muscle lisse vasculaire, de la résistance aux espèces réactives de l’oxygène, de la consommation d’oxygène mitochondriale, et du système immunitaire. Les suites de cette caractérisation se focaliseront sur des études transcriptomiques et génétiques, en particulier sur la région d’intérêt du chromosome XDecompression Sickness is one of the most serious hazards for divers. It is usually admitted that DCS origins from circulating bubbles. However, a strong inter-individual variability exists between divers, resulting in a poor correlation between bubble grade and DCS symptoms. Several physiological mechanisms have been linked with DCS, but none of them appeared to be determinant in the onset of the pathology. In this context, medicine precision techniques may offer new insights, with a broader approach.During this thesis, we used proteomics to investigate changes of the plasma proteome of rats and divers during diving, with and without DCS, and aimed at finding biomarkers of early DCS development. We found that acute inflammation may play a role in the onset on DCS, and that proteomics may be fitted to look for new biomarkers. We also used a selection protocol to create a new DCS resistant rat strain, which was significantly more resistant than classic Wistar rats. Moreover, DCS resistance was gained in a matter of only 2 reproductions cycles (only 1 for females), which gives evidence of heritable components of DCS resistance/susceptibility that might be carried out by the X chromosome. A characterization of this DCS resistant strain showed a number of physiological adaptations gained during the selection process. Indeed, DCS resistant rats showed a decreased mitochondrial oxygen global consumption, a decrease of vascular smooth muscle contraction and relaxation as well as a raise of neutrophils count among males.Further characterization of the DCS resistant strain will focus on transcriptomic and genetic studies, especially on the genomic region of interest located on the X chromosome
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Bisplinghoff, Jill Aliza. "Biomechanical Response of the Human Eye to Dynamic Loading." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/31880.
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Blindness due to ocular trauma is a significant problem in the United States considering that each year approximately 500,000 years of eyesight are lost. The most likely sources of eye injuries include sports related impacts, automobile accidents, consumer products, and military combat. Out of the 1.9 million total eye injuries in the country, more than 600,000 sports injuries occur each year and 40,000 of them require emergency care. In 2007, approximately 66,000 people suffered from vehicle related eye injuries in the United States. Of the vehicle occupants sustaining an eye injury during a crash, as many as 15% to 25% sustained severe eye injuries and it was shown that within these severe eye injuries as many as 45% resulted in globe rupture.
The purpose of this thesis is to characterize the biomechanical response of the human eye to dynamic loading. A number of test series were conducted with different loading conditions to gather data. A drop tower pressurization system was used to dynamically increase intraocular pressure until rupture. Results for rupture pressure, stress and strain were reported. Water streams that varied in diameter and velocity were developed using a customized pressure system to impact eyes. Intraocular pressure, normalized energy and eye injury risk were reported. A Facial and Ocular Countermeasure Safety (FOCUS) headform was used to measure the force applied to a synthetic eye during each hit from projectile shooting toys. The risk of eye injury for each impact was reported. These data provide new and significant research to the field of eye injury biomechanics to further the understanding of eye injury thresholds.
Master of Science
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Kusano, Mariana Bar. "A antropologia de Edith Stein: entre Deus e a filosofia." Pontifícia Universidade Católica de São Paulo, 2009. https://tede2.pucsp.br/handle/handle/2136.
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Previous issue date: 2009-12-15Conselho Nacional de Desenvolvimento Científico e Tecnológico
The purpose of this project is the study of Edith Stein s (1891-1942) philosophical and theological anthropology and its implications on pedagogy. In this sense, Stein s anthropology presents itself as a great effort to comprehend the human being s profound structure, considering the relations established with things, with other human beings and, finally , with God. Her analysis start based on Husserl s phenomenological method and, afterwards, are submitted to Tomas de Aquino s metaphisical indagations. On this movement between Husserl s phenomenology and Tomas de Aquino s metaphisics, Edith Stein describes the essencial constitution of the human being as constituent of body, soul and spirit as well as this essencial structure s individuation. Edith Stein s analysis on the human being comes from a pedagogical requirement and, for this reason, this project presents as a hypothesis the attempt to demonstrate how the anthropology of philosophical nature and the anthropology that lies on Revealed data can constitute as the fundaments of the pedagogy practice and theory. For that, many writings from the author and from scholars of the author have been studied in order to exemplify and confirm the analysis and interpretations on the subject-matter
O objeto deste trabalho é voltado para o estudo da antropologia filosófica e teológica de Edith Stein (1891-1942) e as suas implicações com a pedagogia. Neste sentido, a antropologia de Stein se apresenta como um largo esforço em compreender a estrutura profunda do ser humano, tanto na relação que ele estabelece com as coisas, como na relação que ele mantém com outros seres humanos e, por fim, na sua relação com Deus. Suas análises procedem do método fenomenológico de Husserl para serem, posteriormente, submetidas à indagação metafísica de Tomás de Aquino e, neste movimento, que vai da fenomenologia ao tomismo, Stein descreve a constituição essencial do ser humano, enquanto formado por corpo, alma e espírito, bem como a individuação dessa estrutura essencial. A análise steiniana sobre o homem parte de uma exigência pedagógica e, por esta razão, o presente trabalho apresenta como hipótese a tentativa de demonstrar de que maneira a antropologia de cunho filosófico e a antropologia que repousa sobre os dados Revelados, constituem o fundamento da prática e da teoria pedagógica. Para isso, foram solicitados diversos textos da autora e alguns estudiosos de sua obra, a fim de iluminar, exemplificar e constatar as análises e interpretações sobre o tema aqui pesquisado
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Cavers, Andrew. "Mechanical strain bioreactor design and assessment for culture of human airway smooth muscle." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/59236.
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Bioreactors capable of subjecting cells and tissues to time-varying mechanical strain are one aspect of simulating in vivo conditions. A bioreactor to impart arbitrary strain waveforms on cells or tissue scaffolds for loading conditions found in the airway was designed and developed and, in the process, it was determined that there are sources of experimental error which could invalidate bioreactor experiments if not properly mitigated. Without effective design and validation, bioreactors can impart significantly different stimuli than the assumed experimental conditions. Cyclic strain is thought to play a role in airway remodeling by mediating cytoskeletal contraction of the airway smooth muscle. In vitro experiments have demonstrated varying changes to the cytoskeleton depending on experimental conditions. Based on literature review, the strain waveform, magnitude, mechanical properties of the substrate, and anisotropy of the strain stimulus may all affect airway smooth muscle (ASM) differentiation. A bioreactor capable of imparting a broad range of strain stimulus was developed using stepper motors as actuators to allow open-loop control. Any changes in the cells subjected to cyclic strain in these bioreactors would be assumed to correlate with cyclic strain, but a poorly designed bioreactor could introduce confounding experimental stimuli which could easily invalidate the experiment. Heat generated by the actuators can overheat the cell cultures. Vibration might alter the cytoskeletal response. Strain response across the substrate can drastically vary from modeling predictions depending on the loading conditions and how the substrate has been constrained. Methods of mitigating heat generation and transfer were developed. The vibrations emitted by the two stepper motor options were evaluated. A method of mapping the substrate was developed such that nonplanar strains across the substrate surface could be characterized to validate the experimental conditions prior to testing. Finally, ASM cells were subjected to cyclic and static strain on PDMS substrates and cell realignment evaluated. Cells were noted to realign in the cyclic strain tests, as has been reported in several earlier publications, but also realigned under static strain conditions. The bioreactor design objectives were met.Applied Science, Faculty of
Graduate
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Towler, James Charles. "Transcriptome activity of human cytomegalovirus (strain Merlin) in fibroblasts, epithelial cells and astrocytes." Thesis, Connect to e-thesis record to view abstract. Move to record for print version, 2007. http://theses.gla.ac.uk/42/.
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Thesis (Ph.D.) - University of Glasgow, 2007.Ph.D. thesis submitted to the Division of Virology, Institute of Biomedical and Life Sciences, University of Glasgow, 2007. Includes bibliographical references. Print version also available.
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Dong, Honglin. "The immunomodulatory effect of a probiotic strain Lactobacillus casei Shirota on human volunteers." Thesis, University of Reading, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541970.
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Marriott, H. M. "Unstructured tetrahedral elements for explicit large strain, dynamic impact on human body components." Thesis, Swansea University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638006.
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Modelling the human body during impact with the use of the finite element method is of great interest and importance and is frequently used within the car and sport industry. The difficulties in using the finite element method for those situations described, lies in modelling the complex geometries of the human body successfully and being able to simulate the material properties of the human body. This thesis explores different numerical techniques that have been developed to model the human body more effectively. Structured hexahedral element are insufficient to model complex human geometries, hence tetrahedral elements have been concentrated on. In previous research a standard constant pressure tetrahedra and an average nodal pressure tetrahedra have been developed. This thesis explores new tetrahedral formulations, so as to overcome the inadequacies of the standard constant pressure and average nodal pressure tetrahedra. A split operator developed for solids, by Zienkiewicz et al based on a fluid mechanics algorithm which incorporates the time step splitting procedure originally proposed by Chorin is implemented. In addition a combined algorithm of the average nodal pressure and the split operator was proposed. The average nodal pressure was also noted to have poor behaviour when modelling bending dominated problems. The average deformation gradient tensor tetrahedra was developed and comparisons were made with the standard hexahedral element. Due to the average deformation gradient tensor tetrahedral element not exhibiting excessive stiffness the deformations under impact can create distorted elements and negative element volumes can occur, hence mesh quality enhancement was introduced. Finally several numerical examples are presented to demonstrate the applicability of the numerical techniques discussed within the thesis. The human body component used to demonstrate the theory is the lower leg.
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Aldujaily, Esraa Abdulaal. "An investigation of tumour-associated macrophages and statin therapy in human pulmonary adenocarcinoma." Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/43086.
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Introduction: Pulmonary adenocarcinoma represents a major area of unmet clinical need in cancer treatment. Recent advances in immunotherapy which target the PD-L1 immune checkpoint promise great improvements in outcomes for some patients. The immune system offers several other possible targets. Tumour associated macrophages (TAMs) are a common feature of lung tumour stroma. Epidemiological data have indicated a possible role of statins in reducing cancer mortality via their anti-inflammatory effects, but the mechanisms underpinning this are not clear. The possible roles of pro-tumour versus anti-tumour macrophages were investigated in lung adenocarcinomas, and the possibility of influencing this axis with statin drugs. Methods: Immunohistochemical evaluation was used with phenotyping of TAMs using multiplex immunohistochemistry in tissue microarray sections of about 300 lung adenocarcinomas with matched clinicopathological data. Quantitative digital pathology, using Hamamatsu scanner images and Visiopharm software to count and phenotype TAMs in TMA sections. Results: It has been found that the pro-tumourigenic (CD68+CD163+) TAM numbers are elevated in invasive versus in situ tumour regions. Interestingly, statin users have significantly lower protumourigenic macrophage numbers than non-statin users, significantly in areas of in situ tumour growth in comparison to invasive lesions. Tumours in statin users were also of significantly lower histological grade, showing a higher percentage of in situ components than non-statin users. Conclusion: Automated image analysis methods efficiently count and classify macrophages in tumour tissue. Statin therapy is related to macrophage class, specifically within in situ lesions. These data support a model whereby statins target protumourigenic TAMs in early disease, highlighting their potential as cancer-preventive agents.
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Jensen, Elisabeth Rose. "In vivo quantification of three dimensional volumetric strain in the human tibialis anterior." Thesis, College of Medicine - Mayo Clinic, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10111521.
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Intramuscular pressure (IMP), which is closely correlated with both active and passive muscle tension, may become a useful supplement to current clinical tools as a means to quantify individual muscle-generated force. A continuing challenge associated with this measure is its non-uniform distribution, which is not yet fully understood. Several studies have observed that pressure increases with muscle depth. Conservation of mass suggests that these regional pressure differences may result from non-uniformly distributed changes in local tissue volume. Therefore, the overarching goal of this work was to characterize volumetric strain distribution in skeletal muscle as a means to better understand the mechanism driving the non-uniform IMP distribution.
Three-dimensional volumetric strain distribution had not been previously quantified in skeletal muscle; therefore the bulk of this thesis work revolved around developing and validating a method for this purpose using cine Phase Contrast (CPC) magnetic resonance imaging (MRI). CPC MRI has been previously used to quantify 2D strain distribution in skeletal muscle. Fortunately, the method lends itself to 3D measurements using multiple slice data collection, but this requires a lengthy data acquisition time. We chose to develop the method during passive tension of the human tibialis anterior (TA), because passive tension is closely correlated with IMP and the motion repeatability is more readily controlled and maintained for an extended duration than active tension.
As hypothesized, volumetric strain was found to be non-uniformly distributed during passive tension of the human TA with a decreasing trend from the anterior (superficial) to the posterior (deep) muscle regions. These data align with previously observed trends of decreasing IMP near the muscle surface and may provide important insight into ideal sensor placement regions to maximize measurement repeatability. These results advance our understanding of the tension-IMP relationship in muscle by providing insight into the mechanism behind the non-uniform distribution of IMP. Furthermore, this work has strong potential to contribute to a computational model relating IMP to muscle tension by way of volumetric strain.
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Diston, David. "Characterisation and UV inactivation of bacteriophages infecting human-specific Bacteroides strain GB-124." Thesis, University of Brighton, 2010. https://research.brighton.ac.uk/en/studentTheses/5de499d2-4802-476e-b163-e4d37087df54.
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The pathogens contained in human faecal material can present a significant risk to human health, when discharged into surface waters. A recently isolated strain of Bacteroides spp., (GB-124) has shown good ability to detect viruses (phages) in waters exclusively contaminated by human faecal material, with widespread geographical applicability, proving a low-cost microbial source tracking tool (MST). However, little is known about the morphology, ecology and inactivation of phages capable of infecting strain GB-124 during UV-B (representing the primary germicidal portion of sunlight) and UV-C radiation (a common tertiary disinfection stage in wastewater treatment). Therefore in order to address this knowledge gap, a total of twenty phages were isolated from municipal wastewater and characterised using transmission electron microscopy (TEM) and host range assessment. Ultraviolet radiation (UV) inactivation kinetics were determined using two phases of laboratorybased collimated beam experiments using UV-B and UV-C wavelengths.
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Rostvik, Maia. ""Hemma på min gata i stan..." : Tillhörighet, identitetsskapande och fritid bland unga flickor i Gottsunda." Thesis, Uppsala universitet, Kulturgeografiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-145239.
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Kemper, Andrew Robb. "Material Properties of Human Rib Cortical Bone from Dynamic Tension Coupon Testing." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/43709.
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The purpose of this study was to develop material properties of human rib cortical bone using dynamic tension coupon testing. This study presents 117 human rib cortical bone coupon tests from six cadavers, three male and three female, ranging in age from 18 to 67 years old. The rib sections were taken from the anterior, lateral, and posterior regions on ribs 1 through 12 of each cadaver's rib cage. The cortical bone was isolated from each rib section with a low speed diamond saw, and milled into dog bone shaped tension coupons using a small computer numerical control machine. A high-rate servo-hydraulic Material Testing System equipped with a custom slack adaptor, to provide constant strain rates, was used to apply tension loads to failure at an average rate of 0.5 strains/sec. The elastic modulus, yield stress, yield strain, ultimate stress, ultimate strain, and strain energy density were determined from the resulting stress versus strain curves. The overall average of all cadaver data gives an elastic modulus of 13.9 GPa, a yield stress of 93.9 MPa, a yield strain of 0.883 %, an ultimate stress of 124.2 MPa, an ultimate strain of 2.7 %, and a strain energy density of 250.1 MPa-strain. For all cadavers, the plastic region of the stress versus strain curves was substantial and contributed approximately 60 strain % to the overall response and over 80 strain % in the tests with the 18 year old cadaver. The rib cortical bone becomes more brittle with increasing age, shown by an increase in the modulus (p < 0.01) and a decrease in peak strain (p < 0.01). In contrast to previous three-bending tests on whole rib and rib cortical bone coupons, there were no significant differences in material properties with respect to rib region or rib level. When these results are considered in conjunction with the previous three-point bending tests, there is regional variation in the structural response of the human rib cage, but this variation appears to be primarily a result of changes in the local geometry of each rib while the material properties remain nearly constant within an individual.Master of Science
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Howes, Meghan K. "Injury Mechanisms, Tissue Properties, and Response of the Post-Mortem Human Abdomen in Frontal Impact." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/24382.
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Motor vehicle collisions (MVCs) are a leading cause of injuries and injury-related fatalities in the United States. The National Highway Traffic Safety Administration (NHTSA) reported over 21,250 vehicle occupant fatalities in 2011, with 1,240,000 injuries sustained by passenger car occupants alone. MVCs are a common cause of blunt abdominal injuries. It has been reported that approximately 9,000 front seat occupants sustain moderate to severe abdominal injuries in frontal MVCs in the United States each year. A detailed understanding of the occurrence and mechanisms of abdominal injuries, as well as knowledge of the biomechanical response and tolerance of the abdomen in crash-specific loading modes, could benefit the reduction of abdominal organ injury incidence in MVCs. Therefore, the objective of the research presented in this dissertation was to characterize abdominal injury mechanisms, tissue failure thresholds, and internal organ response to blunt impacts of the abdomen. Field accident data from the Crash Injury Research and Engineering Network (CIREN) database were analyzed to determine the occupant and crash characteristics associated with crash-induced hollow abdominal organ injuries. Dynamic equibiaxial tension tests were conducted on tissue samples obtained from the human post-mortem stomach, small intestine, and colon to characterize the material properties and failure tolerance of these tissues. The effects of cadaver orientation on the relative position of the abdominal organs of two cadavers were quantified, and high-speed biplane x-ray imaging was used to investigate the relative kinematics of the thoracic and abdominal organs of four cadavers in response to crash-specific loading modes. Test configurations included blunt abdominal and thoracic impacts and driver-shoulder seatbelt loading. The motivation for this research was to advance efforts toward abdominal organ injury mitigation in MVCs, with each aspect of this research generating novel injury biomechanics data with applications for future experimental testing and finite element modeling.Ph. D.
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Tsantrizos, Anthony. "Internal deformation and strain of human lumbar intervertebral discs subjected to multi-axial loads." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86056.
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Morphological and clinical signs of lumbar intervertebral disc disruption are pronounced in the posterior and postero-lateral inner annulus fibrosus. The regional intervertebral disc predisposition to disruption suggests that intradiscal stresses and strains may also be region specific and possibly initiate the disruption. Quantitative data describing intradiscal deformations have been limited to the mid-sagittal plane using techniques that compromise the intervertebral disc integrity. No experimental study has quantified intradiscal strain patterns. The initial objectives of the present work were to use experimental cadaveric methods and finite element techniques to develop and validate methods of measuring intradiscal deformations and strains along the complete mid-transversal plane using a fine wire grid.Subsequently, these methods were used to quantify intradiscal deformations and strains in healthy and degenerated intervertebral discs during sub-maximal loads. Eighteen healthy and degenerated intervertebral discs were subjected with wires placed within and beads glued along their mid-traversal plane surface, to compression, extension, flexion and lateral bending. Cramo-caudal radiographs at unloaded and loaded steps documented wire and bead positions. Intradiscal nucleus pulposus displacements, circumferential, radial and shear strains in the annulus fibrosus and transitional zone under load were compared among all anatomical regions and between healthy and degenerated intervertebral discs.
The methods develop to estimate intradiscal strains from intradiscal wire intersection displacements demonstrated a relative overall accuracy of 2.9% (i.e. percent error from theoretical estimations). Generally, intradiscal circumferential and radial strains decreased from the transitional zone to the annulus fibrosus and increased at the side of bending during all bending conditions. Circumferential and radial strain peaks were observed in the postero-lateral regions even in healthy intervertebral discs during extension and lateral bending. Shear strains were generally uniform within the healthy intervertebral disc. Degeneration significantly increased intradiscal circumferential, radial and shear strains during all bending conditions (particularly in the postero-lateral regions). The increased nucleus pulposus migration in degenerative intervertebral discs appeared to have caused the increases in circumferential and radial strains and to some extent perhaps increases in shears strains.
The inner postero-lateral annulus fibrosus is predisposed to excessive normal circumferential and radial strains early on which coincide with morphological changes observed in the same regions. This observation suggests a predisposition to failure likely due to an inability of resisting delaminating normal strains. Furthermore, the increased nucleus pulposus migration observed in degenerated intervertebral discs appears to shift the pivot point during bending movements more posterior, which consequently forces the postero-lateral regions to consistently experience higher circumferential and radial strains. These effects may contribute to the segmental instability observed in degenerated motion segments prior to intervertebral disc failure.
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Demarchi, Luciana. "A CONCEPÇÃO SOBRE SER HUMANO PARA O DISCENTE DO CURSO DE ADMINISTRAÇÃO: APROXIMAÇÕES COM A FENOMENOLOGIA DE EDITH STEIN." Universidade Metodista de São Paulo, 2013. http://tede.metodista.br/jspui/handle/tede/45.
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Previous issue date: 2013-09-12Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The great revolutions that the official story reports, present a common aspect: the evolution of the communication process coupled with technological developments. Since the twentieth century, the information began to circulate in scalar number and speed. The interdependence and interconnectedness of countries, nations and people narrowed because mobility in virtual space, progressively relativizing distances and geophysical spaces. However, the amount of knowledge, scientific improvement and economic development is not enogh to answer, specifically, issues that spread among the human kind. In this scenario, the present work aims to close the gap among the concept of human being based on students from the administration and the existential categories presents at Edith Stein s studies, focused on specific objectives: Understand what is human being is for to the administration course students in a HEI Confessional at the ABC Paulista ; describe what human being is based on the Edith Stein s phenomenological theory; seek convergence, divergence and / or idiosyncrasies between reports from administration students in an HEI Confessional at ABC Paulista and Edith Stein s theory. To this end, five reports of administration students were obtained, which allowed approximations, convergence-divergence with the analytic conception categories of the human being at the Edith Stein s theory for each subject, based on the master question: " what is human to you? ". After that, the interviews were analyzed with reference in the work of Edith Stein ( eidetic phenomenology ) , Castro (2003 ) , Flauzino (2012 ) and Stanislaus (2010 ) , fulfilling the following steps : naive reports lateralization, sense units assesment, phenomenological categories survey and analysis, which enabled the inter subjective and objective dialogue, with the theoretical assumptions about the topic in spot. Those categories are: 1. Physical and Living Body. 2. Soul; Psychophysical Subject 3. Community. From the analysis of the categories, it was observed that the concept of human being converges to the unity of the being concept, being concept that this is composed of a living body, psyche and soul, in order to facilitate their relationship with each other and with the environment. You can not be human, without an encounter with other human being, without mutual respect, without the freedom to be what you are. The communitarian dimension, in which it is only possible to carry humanity through acts of freedom, respect and compassion, came up from the reports. It was also unveiled within these reports, that when it human life is performed smoothly when it is achieved entirety. Power will then through prove the phenomenon , get a new way of looking, thinking and questioning practices experienced in Administration Science, contributing to the critical mass for applied social sciences administration built, reflecting on what's the core and more structuring at the administration student.
As grandes Revoluções que a história oficial relata apresentam um aspecto comum: a evolução do processo de comunicação aliada à evolução tecnológica. A partir do Século XX, as informações passaram a circular em número e em velocidade escalares. A interdependência e a interligação dos países, nações e pessoas estreitaram-se, pois a mobilidade no espaço virtual, progressivamente, relativiza as distâncias e os espaços geofísicos. Todavia, a avalanche de conhecimento, de aprimoramento científico e de desenvolvimento econômico parece não ser suficiente para responder, concretamente, as questões que ainda assolam a humanidade. Neste cenário, o presente trabalho tem por objetivo aproximar a concepção de ser humano para discentes do curso de administração com as categorias existenciais presentes no pensamento de Edith Stein, por meio dos objetivos específicos: Compreender o que é ser humano para o discente do curso de administração em uma IES Confessional do ABC Paulista; descrever o que é ser humano a partir do pensamento fenomenológico de Edith Stein; buscar convergências, divergências e/ou idiossincrasias entre os relatos de discentes do curso de administração em uma IES Confessional do ABC Paulista e o pensamento de Edith Stein. Para tal, foram colhidos cinco relatos de discentes de administração, por meio dos quais foram feitas aproximações, convergências-divergências com as categorias analíticas da concepção de ser humano no pensamento de Edith Stein para cada sujeito, tendo como questão norteadora: o que é ser humano para você ? Após a coleta, as entrevistas foram analisadas tendo como referência os trabalhos de Edith Stein (fenomenologia eidética), Castro (2003), Flauzino (2012) e Estanislau (2010), cumprindo as seguintes etapas: literalização dos relatos ingênuos, levantamento das unidades de sentido, levantamento e análise fenomenológica das categorias, as quais possibilitaram o diálogo intersubjetivo e objetivo com os pressupostos teóricos sobre o tema em pauta. Categorias estas denominadas de: 1. Corpo Físico e Corpo Vivente; 2. Espírito; Sujeito Psicofísico; 3. Comunidade. A partir da análise das categorias, observou-se que a concepção de ser humano conflui para a unidade do ser, ser este que é composto por corpo vivente, psique e espírito, de forma a possibilitar relações com o outro e com o ambiente. Não é possível ser humano sem um encontro com o outro, sem o respeito mútuo, sem a liberdade de ser o que se é. Emerge a dos relatos a dimensão comunitária, somente na qual se é possível realizar a humanidade, por meio de atos de liberdade, respeito e de compaixão. Desvelou-se também dentro destes relatos, que quando se é humano, a vida em seu todo é realizada de forma harmoniosa. Poder-se-á, então, por meio do revelar-se do fenômeno, obter uma nova forma de olhar, de pensar e questionar as práticas vivenciadas na Administração, contribuindo com a formação de uma massa crítica para as ciências sociais aplicadas da administração, ao refletir sobre o que há de mais estruturante e nuclear no discente de administração.
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Calkins, Thomas B. "Nanocomposite High Displacement Strain Gauges for use in Human-Machine Interfaces: Applications in Hand Pose Determination." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2627.
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Conductive nanocomposites are finding many uses as multi-functional materials. One recent development involves the creation of high displacement strain gauges, which have potential applications in a variety of engineering roles. The piezoresistive nature of the gauges makes possible their strain sensing capability. The intent of this research is to show that specific High Displacement Strain Gauges can successfully be used in one human-machine interface application that will demonstrate their potential for a range of other human-machine interface applications. This will be shown in the development of these sensors to accomplish hand pose determination. The flexible and inexpensive gauges are attached to several locations on a glove. It is then shown that by linking this glove with software, the position of the hand can be interpreted into the letters of the American Sign Language alphabet. This use of this nanocomposite sensor establishes the potential for future applications. Issues such as accuracy of response, cyclability, recalibration and reliability are discussed. A design of experiments is accomplished in order to evaluate the effects of modification of the gauges in order to overcome these issues. This work develops the potential of these sensors for use in human-machine interface applications such as computer games, remote controls, robotics, prosthetics and virtual reality applications.
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Gao, Liang. "Ultrasound Elasticity Imaging of Human Posterior Tibial Tendon." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/338897.
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Posterior tibial tendon dysfunction (PTTD) is a common degenerative condition leading to a severe impairment of gait. There is currently no effective method to determine whether a patient with advanced PTTD would benefit from several months of bracing and physical therapy or ultimately require surgery. Tendon degeneration is closely associated with irreversible degradation of its collagen structure, leading to changes to its mechanical properties. If these properties could be monitored in vivo, it could be used to quantify the severity of tendonosis and help determine the appropriate treatment. Ultrasound elasticity imaging (UEI) is a real-time, noninvasive technique to objectively measure mechanical properties in soft tissue. It consists of acquiring a sequence of ultrasound frames and applying speckle tracking to estimate displacement and strain at each pixel. The goals of my dissertation were to 1) use acoustic simulations to investigate the performance of UEI during tendon deformation with different geometries; 2) develop and validate UEI as a potentially noninvasive technique for quantifying tendon mechanical properties in human cadaver experiments; 3) design a platform for UEI to measure mechanical properties of the PTT in vivo and determine whether there are detectable and quantifiable differences between healthy and diseased tendons. First, ultrasound simulations of tendon deformation were performed using an acoustic modeling program. The effects of different tendon geometries (cylinder and curved cylinder) on the performance of UEI were investigated. Modeling results indicated that UEI accurately estimated the strain in the cylinder geometry, but underestimated in the curved cylinder. The simulation also predicted that the out-of-the-plane motion of the PTT would cause a non-uniform strain pattern within incompressible homogeneous isotropic material. However, to average within a small region of interest determined by principal component analysis (PCA) would improve the estimation. Next, UEI was performed on five human cadaver feet mounted in a materials testing system (MTS) while the PTT was attached to a force actuator. A portable ultrasound scanner collected 2D data during loading cycles. Young's modulus was calculated from the strain, loading force and cross sectional area of the PTT. Average Young's modulus for the five tendons was (0.45±0.16GPa) using UEI. This was consistent with simultaneous measurements made by the MTS across the whole tendon (0.52±0.18GPa). We also calculated the scaling factor (0.12±0.01) between the load on the PTT and the inversion force at the forefoot, a measurable quantity in vivo. This study suggests that UEI could be a reliable in vivo technique for estimating the mechanical properties of the human PTT. Finally, we built a custom ankle inversion platform for in vivo imaging of human subjects (eight healthy volunteers and nine advanced PTTD patients). We found non-linear elastic properties of the PTTD, which could be quantified by the slope between the elastic modulus (E) and the inversion force (F). This slope (ΔE/ΔF), or Non-linear Elasticity Parameter (NEP), was significantly different for the two groups: 0.16±0.20 MPa/N for healthy tendons and 0.45±0.43 MPa/N for PTTD tendons. A receiver operating characteristic (ROC) curve revealed an area under the curve (AUC) of 0.83±0.07, which indicated that the classifier system is valid. In summary, the acoustic modeling, cadaveric studies, and in vivo experiments together demonstrated that UEI accurately quantifies tendon mechanical properties. As a valuable clinical tool, UEI also has the potential to help guide treatment decisions for advanced PTTD and other tendinopathies.
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Hurley, Nicole Elizabeth. "Modulating the Functional Contributions of c-Myc to the Human Endothelial Cell Cyclic Strain Response." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19822.
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With each heartbeat, major arteries experience circumferential expansion due to internal pressure changes. This pulsatile force is called cyclic strain and has been implicated in playing a pivotal role in the genetic regulation of vascular physiology and pathology. This dissertation investigates the hypothesis that in human umbilical vein endothelial cells (HUVEC), pathological levels of cyclic strain activate the c-Myc promoter, leading to c-Myc transcription and downstream gene induction. To determine expression and time-dependency of c-Myc in HUVEC, mRNA and protein expression of c-Myc under physiological (6-10% cyclic strain) and pathological conditions (20% cyclic strain) were studied. Both c-Myc mRNA and protein expression increased more than three-fold in HUVEC (P4-P5) cyclically-strained at 20%. This expression occurred in a time-dependent manner, peaking in the 1.5-2 hour range and falling to basal levels by 3 hours. Subsequently, the mechanism of c-Myc transcription was investigated by using specific inhibitors to modulate c-Myc transcriptional activation. These compounds, obtained from the University of Arizona Cancer Center, attenuated cyclic-strain-induced c-Myc transcription by about 50%. Having established this reduction in expression, it was investigated how these effects modulate downstream genes that are regulated by c-Myc. The results indicate that direct targeting of the c-Myc promoter may decrease stretch-induced gene expression of vascular endothelial growth factor (VEGF), proliferating cell nuclear antigen (PCNA) and heat shock protein 60 (HSP60). These findings may help in the development of a novel therapeutic opportunity in vascular diseases.
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Pang, Kam-man. "The bacteriology, structure and composition of black stains on human permanent teeth in Hong Kong." [Hong Kong] : The University of Hong Kong, 1995. http://sunzi.lib.hku.hk/HKUTO/record/B38627966.
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El-Hossary, Wafaa Hassanein Hassan. "The effect of cyclic tensile strain on gene expression of cultured human periodontal ligament cells." Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509041.
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Objectives: To analyse the changes in gene expression in a population of human periodontal ligament (HPDL) cells exposed to cyclic tensile strain in a three dimensional culture system. Results: Cells derived from extracted teeth were shown to represent a mixed population with greater than 95% of cells expressing markers characteristic of periodontal ligament fibroblasts with an oestobastic phenotype with a smaller sub-population (2-3%) of stem cells. Cells from several different donors were subjected to an applied tensile strain (5%) and compared to unstressed controls. RNA extracted immediately post-stress was analysed to determine changes in gene expression. Microarray data indicated a total of 164 genes responding to the applied strain, 38% of which have no known function. qRT-PCR analysis of HAS1, NR4A2, FOS, INHBA, FOSL2, RUNX2, ATF4, FOSL1, SP7, COL1A1, COL3A1, MMP1, MMP2, MMP3 and TIMP3 expression levels confirmed the microarray data. Further analysis of the data highlighted changes in expression of CLDN4, BCOR, PROK2 and INHBA genes known to be associated with inherited orofacial disorders. Conclusion: This study has shown that the periodontal ligament fibroblasts derived from extracted teeth and cultured in vitro in 3D 'in-vivo-like' constructs can be induced to respond to mechanical stimuli. The molecular events detected in periodontal ligament cells subjected to cyclic tensile strain direct the cell population to remodel the entire periodontium (cells and matrices) in a process involving cell migration. This study presents several new findings including the first report of the involvement of HAS1, NR4A2 and FOSL2 in the response of HPDL cells to mechanical stimulation, the first report for the of modulation CLDN4, BCOR, and PROK2 genes by mechanical perturbation, and the differential induction of SP7 isoforms by mechanical stimulation in HPDL.
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彭錦文 and Kam-man Pang. "The bacteriology, structure and composition of black stains on human permanent teeth in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B38627966.
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Cavazzoni, Giulia. "In vitro characterization of the three-dimensional strain pattern in human vertebrae affected by metastases." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/22880/.
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La colonna vertebrale è la principale sede di metastasi, le quali possono alterare la normale distribuzione dei tessuti ossei e ridurre la capacità della vertebra di sostenere carichi. L’instabilità spinale causata dalle metastasi, tuttavia, è di difficile determinazione. La caratterizzazione meccanica delle vertebre metastatiche permetterebbe di identificare e, di conseguenza trattare, quelle ad alto rischio di frattura.
In questo studio, ho valutato il comportamento meccanico a rottura di vertebre umane affette da metastasi misurando in vitro il campo di deformazione.
Undici provini, costituiti da due vertebre centrali, una metastatica e una sana, sono stati preparati e scansionati applicando carichi graduali di compressione in una micro-tomografia computerizzata (μCT). Le deformazioni principali sono state misurate attraverso un algoritmo globale di Digital Volume Correlation (DVC) e successivamente sono state analizzate.
Lo studio ha rivelato che le vertebre con metastasi litiche raggiungono deformazioni maggiori delle vertebre sane. Invece, le metastasi miste non assicurano un comportamento univoco in quanto combinano gli effetti antagonisti delle lesioni litiche e blastiche. Dunque la valutazione è stata estesa a possibili correlazioni tra il campo di deformazione e la microstruttura della vertebra. L'analisi ha identificato le regioni in cui parte la frattura (a più alta deformazione), senza identificare, in termini microstrutturali, una zona preferenziale di rottura a priori. Infatti, alcune zone con un pattern trabecolare denso, presunte più rigide, hanno mostrato deformazioni maggiori di quelle dei tessuti sani, sottolineando l’importanza della valutazione della qualità del tessuto osseo.
Questi risultati, generalizzati su un campione più ampio, potrebbero essere utilizzati per implementare nuovi criteri negli attuali sistemi di valutazione dell'instabilità spinale.
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Sandora, Normalina. "Regeneration of decellularised tendon by human mesenchymal stem cells in response to uniaxial tensile strain." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/16429/.
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Injury of ligaments is very common, and a total tear of the anterior cruciate ligament (ACL) demands replacement. Ideally, a graft for ligament replacement should be able to regenerate into a native like ligament, and restore physiological and anatomical function immediately after transplantation. The University of Leeds has developed a protocol to generate an acellular tendon scaffold derived from allograft/ xenograft using decellularisation technology. The aims of the study were to study the differentiation of human bone marrow derived multipotential stromal cells (BM-MSC) seeded onto the decellularised porcine patella tendon scaffold in response to cyclic tensile strain. Porcine patellar tendons were harvested and decellularised using the Leeds protocol. The decellularised tendon scaffolds were then characterised to determine their: (i) acellularity, (ii) histoarchitecture, (iii) extracellular matrix components (iv) levels of DNA (v) sterility, and (vi) biocompatibility. The decellularisation protocol was found to have minimal effect on the tissue histoarchitecture, and consistently generated sterile, non-toxic acellular scaffolds among different batches, with 98 – 99 % DNA removal compared to native tissue. Both porcine and human BM-MSCs were characterised using a range of antibodies to CD markers and trilineage differentiation and shown to have properties consistent with multipotential stromal cells. Human BM-MSCs were seeded directly onto appropriately sized samples of porcine patella tendon scaffolds at 1 x 105 cells.cm-2 for 12 hours, and then transferred to culture wells of TenCell-1 (a physically interactive rig for delivery of cyclic tensile strain). The cell-seeded tendon scaffolds were cultured either statically or with 4, 6 or 8 % cyclic tensile strain for 4/24 hours at 1 Hz, for 7 days. The response of the cells to cyclic tensile strain was investigated using viability assays (Live/Dead assay and ATPlite™ assay), histology, immunohistochemistry and gene expression analysis (RT-qPCR and gel electrophoresis). The mechanical properties of the scaffolds before and after incubation with cells were determined using uniaxial tensile testing. Under 4, 6 and 8 % cyclic tensile strain, the cell seeded scaffolds had a histological appearance of tendon-like tissue. When cultured under 6 and 8 % cyclic tensile strain, there was evidence that the MSCs were differentiating into tenogenic cells by expressing scleraxis, tenascin C, collagen I and collagen III genes. Cell-seeded scaffolds cultured under 6 % cyclic tensile strain had the highest viability and the matrix stiffness, was significantly increased compared to cell-seeded scaffolds cultured at 4 or 8 % cyclic tensile strain. The cell-seeded scaffolds incubated statically for 7 days showed matrix disorganization, had lower cell viability and less cell infiltration compared to samples incubated with cyclic strain.
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Manara, Serena. "Strain-level (meta)genomic profiling of bacteria from hospital pathogens to non-human primate commensals." Doctoral thesis, Università degli studi di Trento, 2019. http://hdl.handle.net/11572/243715.
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Studying microbial organisms at the level of single genetic variants (strains) is key not only for human pathogens but also for commensal members of the human microbiome. However, several limitations make isolation-based methods only partially effective in surveying the complexity of host-associated microbial communities. Novel biotechnological advances are revolutionizing the study of host-associated microbes, enabling the transition from low-resolution cultivation-based typing to cultivation-free metagenomic characterizations. In my doctoral work, I tested the hypothesis that appropriate analytical tools applied to genomic and metagenomic data can provide information about microbes at a resolution comparable to that of cultivation-based methods. To this end, I employed a set of integrated methods to reconstruct the genome and analyse the functional and transmission patterns of pathogenic and commensal microbes across human and non-human hosts in different contexts. We initially focused on the whole-genome sequencing of a cohort of 184 Staphylococcus aureus infections from patients with a set of diverse diseases at multiple departments of Meyer’s Children Hospital in Florence, Italy. By applying a combination of isolation-based techniques and computational analysis, we surveyed the epidemiology, transmission patterns, and genomic features associated with both highly-studied and under-investigated S. aureus clones. We identified new infective clones and two novel variants of the beta-lactam resistance cassette. We moreover profiled the virulence and resistance factors typically associated with this opportunistic pathogen, observed the dispensability of genes previously considered as putative targets for vaccine development, and tracked the transmission of a newly-emerging epidemic clone. We then focused on the challenging task of extracting strain-level genomic information from cultivation-free metagenomic sequencing of stool samples obtained from mothers and their infants during the first year of life. By applying genetic and pangenomic profiling tools, we showed that the spread of microbiome members can be inferred from metagenomes directly, and we tracked the vertical transmission of microbial strains from mother to her infant and their corresponding transcriptional profiles. This pilot study laid the foundations for larger cohort studies investigating microbiome transmission via metagenomic sequencing. The next step was the application of cultivation-free approaches to identify and survey currently neglected host-associated microbes. In order to explore those species lacking relatively close already sequenced genomes, we performed a large-scale assembly-based analysis to reconstruct high-quality microbial genomes for species and strains in the under-investigated microbiome of non-human primates (NHPs). Overall, less than one-quarter of the recovered genomes were assigned to known species or species previously observed in the human microbiome. The remaining genomes were assigned to over 1,000 new species, which improved the mappable fraction of NHP metagenomes by over 600%. The analysis of this newly-established catalog of NHP-associated species in the context of available human-associated microbial genomes further exposed the loss of biodiversity from wild and captive NHPs to non-Westernized and Westernized human populations, showing that microbiome members shared between NHPs and humans mostly belong to uncharacterized species that are heavily lifestyle-dependent. Through characterization of a cohort of Staphylococcus aureus isolates, tracking of transmission of commensals from mother to infant, and recovering of microbial dark matter associated with non-human primates, we showed that cultivation-free profiling of known and unknown host-associated species can achieve a resolution for comparative genomics that is close to that available for isolate sequencing.
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Stein-Kaempfe, Jacqueline [Verfasser]. "Human Security - Völkerrechtliche Aspekte eines internationalen Sicherheitskonzeptes zu Beginn des 21. Jahrhunderts. / Jacqueline Stein-Kaempfe." Berlin : Duncker & Humblot, 2008. http://d-nb.info/1238359493/34.
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Sinitski, Dzmitry [Verfasser], and Hans-Joachim [Akademischer Betreuer] Schnittler. "Strain-specific interactions of Staphylococcus aureus with human endothelium / Dzmitry Sinitski ; Betreuer: Hans-Joachim Schnittler." Münster : Universitäts- und Landesbibliothek Münster, 2016. http://d-nb.info/1141683342/34.
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Fisher, Ian Alexander. "A mathematical investigation of the influence of skeletal geometry on the mechanics of a prosthetic human hip joint." Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/7881.
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Neal, Emily R. "ESCHERICHIA COLI STRAIN DIVERSITY IN HUMANS: EFFECTS OF SAMPLING EFFORT AND METHODOLOGY." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/984.
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Studies investigating Escherichia coli strain diversity and demographics in human hosts are frequently inconsistent regarding sampling effort and methodology while current strain typing methods are often expensive or laborious. To rectify these inconsistencies, sampling effort was investigated by comparing the diversity of 15-isolate collections to 100-isolate collections from 3 human subjects. Temporal variation in E. coli strain diversity was also studied by collecting 15 isolates once every 6 months. Additionally, strain identification and diversity collected by different sampling methods (fecal swabs vs. anal swabs collected at different times around defecation) were compared to identify any inherent biases in sampling method. This study employed pyroprinting, a new inexpensive and simple strain typing method using pyrosequencing, to generate DNA fingerprints (or pyroprints) based on the Intergenic Transcribed Spacer sequences in the ribosomal RNA operon to differentiate E. coli strains. Differences in strain diversity were apparent when comparing sampling efforts. The sampling effort investigation suggested that certain subjects hosted very large and highly diverse E. coli strain populations such that even 100 isolates may not fully represent E. coli strain populations in human hosts. Instead, the sampling effort required to accurately represent strain demographics may depend on strain richness and evenness within each host. The temporal investigation yielded similar or greater strain abundance and diversity compared to other typing methods in the literature suggesting pyroprinting is a similarly discriminating tool. When agglomerated over time or by subject, no significant differences in diversity were observed between subjects or between sampling methods despite visible differences in strain richness and evenness.
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Tolson, Carla E. "Molecular analysis of Mycobacterium kansasii from human and potable water specimens." Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/103981/1/Carla_Tolson_Thesis.pdf.
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This research investigated whether the environmental mycobacteria Mycobacterium kansasii is linked to outbreaks of pulmonary disease in Queensland. The prevalence of pulmonary disease due to environmental mycobacteria is increasing, however, it's not clear if waterborne M. kansasii are the same as those that cause disease in humans. She developed and compared three DNA-based methods to determine the likely source of M. kansasii and found that Brisbane's municipal water is unlikely to be the infection source. However, waterborne M. kansasii cannot be excluded from areas associated with mining and industry. These findings have been presented at several national and international conferences.
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Bishop, Matthew T. "Role of PRNP codon 129 genotype in defining strain transmission properties of human transmissible spongiform encephalopathy." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4236.
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The human prion protein (PrP) gene (PRNP) codon 129 (M/V) polymorphism is a susceptibility factor for variant Creutzfeldt-Jakob Disease (vCJD) and a major determinant of clinico-pathological phenotype in sporadic CJD. The role of codon 129 in defining susceptibility and strain transmission properties has been investigated in three lines of transgenic mice that express human PrP. The human PRNP gene has directly replaced the murine version, by gene targeting, and variation at codon 129 has given the three genotype lines (HuMM, HuMV, and HuVV). The genetics of these three mouse lines are otherwise identical, and therefore differences in transmission properties can be directly attributable to the codon 129 genotype. vCJD inoculation has shown that all three codon 129 genotype mice are susceptible with a ranking of transmission efficiency of HuMM>HuMV>HuVV. HuMM mice develop the most widespread neuropathology with features similar to human vCJD. Subclinical infection was noted in each mouse line. These data suggest that the vCJD strain is transmissible to humans of each of the three codon 129 genotypes, implying that non-MM cases of human infection with bovine spongiform encephalopathy (BSE) may exist but with long subclinical incubation periods. Inoculation of material from blood transfusion associated vCJD showed no change in transmission properties suggesting that the threat of a future epidemic of human-to-human vCJD infection has not been increased by adaptation of the vCJD strain. However the route of infection, for example via blood transfusion or surgery, may be more efficient that the original oral route of BSE infection. sCJD is classified into six subgroups according to clinico-pathological features, and defined by codon 129 genotype and electrophoretic mobility type (1 or 2) of disease associated PrPSc (MM1, MM2, MV1, MV2, VV1, VV2). Typical cases from each subgroup have shown specific transmission properties suggesting that the subgrouping is defining separate disease strains. The commonest subgroup (MM1) was the most transmissible and the HuVV mouse line the most susceptible host. These data outline the transmission risk from all sCJD types to recipients of each codon 129 genotype should an infection event occur, and show the significant role of recipient codon 129 genotype in defining the clinical or subclinical state and the success or failure of transmission. This is important for determining individual risk following known exposure, and for modelling the potential of iatrogenic infection from sCJD patients.
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Kimber, Philip. "Mechanical strain-induced regulation of vascular endothelial growth factor production by human vascular smooth muscle cells." Thesis, University of Leicester, 2001. http://hdl.handle.net/2381/29387.
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The present thesis investigates the effect of cyclical mechanical strain on the expression of vascular endothelial growth factor (VEGF); a potent cytokine produced by human vascular smooth muscle cells (VSMC). The initial investigations observed the expression of VEGF mRNA and peptide over time and then the effect of increasing the magnitude of strain applied to the cells.;The second area of study was to identify the effect of strain on a candidate intracellular signalling pathway, the mitogen activated protein kinase (MAPK) cascade. The experiments observed the effect of strain on the level of phosphorylated MAPK within the cells and the actual activity of MAPK isolated from cultured human VSMC. The effect of a MAPK pathway inhibitor (PD98059) on the phosphorylated peptide activity was also analysed.;The data submitted in this thesis demonstrates that the expression of VEGF mRNA and peptide are increased in a dose-dependent manner when exposed to cyclical mechanical strain and that the level of phosphorylated MAPK increases likewise. Furthermore, the addition of a MAPK inhibitor not only reduces the level of MAPK activation, but also the expression of VEGF. Taken together, these data identify a potential mechanism whereby strain can directly effect vascular permeability by regulating the expression of VEGF peptide through the MAP kinase cascade.
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Burford, Eva-Maria. "The analysis of the strain level and the predicted human error probability for critical hospital tasks." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1005182.
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South African hospitals, as a result of numerous factors, have the problem of an increasing workload for nursing staff, which in turn may affect patient treatment quality. This project aimed at addressing patient treatment quality specifically from the perspective of worker capabilities by investigating the strain level and predicted human error probability associated with specific patient-centered tasks in the South African health care sector. This was achieved through two independent yet interlinked studies which focused on seven patient-centred tasks. The tasks analysed were the tasks of setting up and changing intravenous medication, administering injection and pill medication, measuring blood glucose, temperature and heart rate and blood pressure. In the first study, work environment and task characteristics, task structure and execution were analysed. In addition to the task execution, the resulting strain levels, in the form of heart rate measures and subjective ratings of workload, were studied. The second study determined the error protocols and predictive error probability within the healthcare environment for the seven pre-defined tasks. The results for the first study established that different organizational and environment factors could affect task complexity and workload. The individual task components and information processing requirements for each task was also established. For the strain analysis, significant results for the tasks were determined for heart rate frequency and the heart rate variability measures, but some of these were contradictory. For the second study, specific error protocols and error reporting data were determined for the hospital where this research was conducted. Additionally the predictive error probability for the pre-defined tasks was determined. This combined approach and collective results indicate that strain and predictive error probability as a result of task workload can be determined in the field as well as being able to identify which factors have an effect on task strain and error probability. The value of this research lies in the foundation that the gathered information provides and the numerous potential applications of this data. These applications include providing recommendations aimed at improving nursing work environment with regards to workload, improving patient treatment as a result of a reduction in errors and the potential foundation these results provide for future research