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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
451

E2F and survivin - key players in cellular proliferation and transformation

Maiti, Baidehi. January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 128-138).
452

Assessment of protective factors for violence risk

Neil, Clare January 2015 (has links)
There is increasing interest in protective factors for violence risk and it has been proposed that consideration of protective factors in addition to risk factors may lead to more balanced and accurate violence risk assessments. Part 1: A systematic review of the literature was conducted to explore the predictive and incremental validity of protective factors assessed using structured professional judgment (SPJ) violence risk assessment tools. Eighteen studies were identified which reported the predictive validity of protective factors for violent behaviour in adolescent and adult males using five different SPJ risk assessment tools. Overall, most studies found that protective factors were associated with the absence of violence. The evidence to support the incremental validity of protective factors (in addition to risk factors) was however less robust and most studies were identified as having a risk of bias which impacted on the potential accuracy and generalisability of the findings. Part 2: Using a pseudo-prospective design, the predictive and incremental validity of protective factors was explored using the Structured Assessment of Protective Factors (SAPROF) and Historical Clinical Risk Management-20 (HCR-20V3) guidelines in a sample of 75 male patients in a high secure forensic mental health inpatient setting. The SAPROF was associated with the absence of different types of violence within the hospital setting (with AUC values for the total SAPROF score ranging from .69 to .74). The SAPROF did not appear to significantly add to the predictive validity of the dynamic risk factors in the HCR-20V3. The Integrative Final Risk Judgment however demonstrated strong predictive validity (with AUC values for different types of violence ranging from .74 to .81) and incremental validity in the prediction of violent behaviour.
453

An exploratory study of the adoption of mobile telecommunications service in order to improve mobile health service development

Grego-Nagel, Anne C. January 1900 (has links)
Doctor of Philosophy / Department of Industrial & Manufacturing Systems Engineering / Malgorzata J. Rys / This dissertation is the result of exploring the phenomenon of the adoption of a service innovation, in particular mobile telecommunications service, with the goal of informing the design of mobile health services. A grounded research study led to the finding that older adults may not abandon a legacy service, such as landline telecommunications service, when they adopted mobile telecommunications service. To further understand the results of the first study, a multidisciplinary literature review was undertaken and resulted in a typology of the factors of individual-level innovation adoption that can be applied by human factors professionals in the field. The three categories of factors included macro environmental, innovation-specific, and human factors. A research analysis of a study done by a county health department provided insights into what older adults contributed to the service production process in healthcare services including which common proxies do not accurately reflect the situations of older adults. A three-state process model of individual-level innovation adoption, which incorporated the role of a legacy system, was developed using the adoption patterns of mobile telecommunications services. In this model, individuals move from a state of using a legacy system to adopting a innovative system while still using the legacy system. After a period of time, the individual moves from the state of dual use to fully abandoning the legacy system and using only the innovative system. A compartmental mathematical model is developed to allow the model to be simulated and future service demand needs can be better predicted. Two decision-making processes were identified to be employed by individuals in the abandonment of a landline telecommunications services. Finally, recommendations for the design of mobile health services are provided.
454

Fighter pilot's performance and mental workload

Mansikka, H. P. January 2016 (has links)
Human information processing consists of multiple and limited resources; some of them are shared while some are separate and non-interchangeable. High pilot mental workload (PMWL) - and the subsequent decline in performance - results from the imbalance between the mental resources available to perform the task and the amount of resources needed to perform it. When the pilot’s proficiency is evaluated, s/he should deliver an acceptable performance while being able to reserve enough mental capacity for the unexpected, additional resource demands. The task demands and cognitive stressors of air combat have potential to degrade pilot performance to an unacceptable level. Therefore, it is important to understand the amount of mental workload the pilots are experiencing and how much spare capacity they have available to cope with the possible additional resource demands. This thesis was aimed at understanding the relationship between PMWL and performance. The approach presented in this thesis was expected to support the development of reliable metrics for predicting the pilot performance under the stress of combat. In terms of practical applications, this thesis contributed to the development of the methodological principles that could help assuring the pilots’ ability to cope with the task demands higher than those experienced during training or proficiency checks. Heart rate (HR) and heart rate variation (HRV) were used as indexes of PMWL. The selection was done for several reasons. HR and HRV measures were accepted by the pilots as they were non-intrusive and they appeared to be objective. In addition, the implementation requirements were by no means excessive. Considering the aims of this thesis, the low diagnosticity of HR/HRV was not an issue. Finally, HR and HRV proved to be sensitive measures of varying task demands – especially when measured together with the pilots’ awareness of the mission requirements. Simulated fighter missions were used to manipulate the pilots’ task demand and to measure their performance and HR/HR. The thesis is constructed around three studies. In the first study, the subjects were required to fly instrument approaches in a high fidelity simulator under various levels of task demand. The task demand was manipulated by increasing the load on the subjects by reducing the range at which they commenced the approach. HR and the time domain components of HRV were used as measures of PMWL. The findings indicated that HR and HRV were sensitive to varying task demands. HR and HRV were able to distinguish the level of PMWL after which the subjects were no longer able to cope with the increasing task demands and their performance fell to a sub-standard level. The major finding of the first study was the HR/HRV’s ability to differentiate the sub-standard performance approaches from the high performance approaches. In the second study, fighter pilots’ performance and PMWL were both measured during a real instrument flight rules proficiency check in an F/A-18 simulator. PMWL was measured using HR and HRV. Performance was rated using Finnish Air Force’s official rating scales. Results indicated that HR and HRV were able to differentiate varying task demands in situations where variations in performance were insignificant. It was concluded that during a proficiency check, PMWL should be measured together with the task performance measurement. In the third study, fighter pilots’ HRV and performance were examined during instrument approaches and air combat. The subjects’ performance was rated by a weapons instructor. In addition, the subjects’ HRV was measured and used as an indicator of PMWL. During the instrument approaches, low performance was associated with high PMWL as expected. However, during the combat phases of the mission, low performance was associated with low PMWL. When the subject’s awareness of the mission requirements was studied, it was found that the combination of low performance and low PMWL was associated with the subjects’ low awareness of the mission requirements. The major finding was that unless the subjects’ awareness of the mission requirements is examined, the relationship between the mental workload and performance during a complex combat mission may be difficult to explain. It is concluded that HR and HRV are sensitive measures of PMWL in a simulated fighter aviation environment. HR and HRV proved to be associated with the changes in task demands and pilots’ performance during simulated instrument approaches and air combat. However, the results of this thesis suggest that measuring just PMWL and performance is not sufficient – especially if the task of interest is complex and dynamic. To fully understand the pilot performance in such environment, the relationship between awareness of the mission requirements, workload and performance needs to be untangled. While this thesis provides encouraging results to understand this phenomena, further research is still needed before awareness of the situation requirements (or more broadly, situation awareness), performance and mental workload can be measured simultaneously, objectively and in real time.
455

Análise da expressão gênica de MyoD, MRF4, miogenina e miostatina nos músculos Bíceps femoris e Gastrocnemius lateralis em duas linhagens de Gallus gallus (corte e postura)

Marchesin, Marcelo de Lima [UNESP] 14 August 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-14Bitstream added on 2014-06-13T19:49:26Z : No. of bitstreams: 1 marchesin_ml_me_rcla.pdf: 512126 bytes, checksum: f1af03206b1ca9a151524c3b6960cca3 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A formação da musculatura esquelética nos membros de frango é um processo complexo, dividido em várias etapas, desde a formação do somito, progenitor da musculatura, até o músculo propriamente dito. O presente trabalho teve o objetivo de caracterizar o perfil de expressão de genes associados aos fatores miogênicos MyoD, MRF4 e Miogenina (responsáveis pela formação e manutenção da musculatura) e Miostatina. Utilizaram-se 40 animais de duas linhagens (20 de corte e 20 de postura), cujos tecidos das coxas e sobrecoxas foram coletados em duas idades (21 e 42 dias póseclosão). A técnica de PCR quantitativa foi empregada nas análises da expressão gênica e os dados obtidos foram analisados com a utilização do programa REST (Ferramenta para análise de expressão relativa - Relative Expression Software Tool) que se baseia em quantificação relativa. Devido à divergência fenotípica no padrão de crescimento das linhagens estudadas, esperava-se encontrar diferenças na expressão de miostatina, as quais não foram confirmadas. Por outro lado, foram verificadas diferenças para MRF4 nos músculos Gastrocnêmio (coxa) e Biceps (sobrecoxa) em ambas as idades, e 9 para Miogenina, em Gastrocnêmio, aos 42 dias; com maior expressão na linhagem CC. A caracterização dos genes estudados foi parcial, abrindo a possibilidade para que outros genes possam ser selecionados com intuito de compreender o desenvolvimento muscular em frangos. / The development of the chicken limb muscles is a complex process, divided into several stages from the initial somite formation to the muscle itself. This study aimed to characterize expression profile of genes associated to myogenic factors MyoD, MRF4 and Miogenin (responsible for muscle formation and maintenance) and Miostatin. It was used 40 animals from two lines (20 broiler and 20 layer), whose thigh and drumstick tissues were collected at two ages (21 and 42 days post-hatch). Gene expression employed techniques of quantitative PCR and data were analyzed by REST program, which is based on a relative quantification. Due to phenotypic divergence in the growth pattern of the strains studied, it was expected to find differences in the expression of miostatin that were not confirmed. On the other hand, differences were found for MRF4, with highest expression in CC line. The characterization of genes studied was partial, opening the possibility that other genes may be selected in order to understand the muscle development in chickens.
456

Estudo de amostras de Staphylococcus coagulase-negativa quanto a formação de biofilme /

Bernardi, Adilson César Abreu. January 2005 (has links)
Orientador: Antonio Carlos Pizzolitto / Banca: Isabel Yoko Ito / Banca: Sérgio Aparecido Torres / Banca: Maria de Lourdes Ribeiro de Souza / Banca: Clarice Queico Fujimura Leite / Resumo: Os Staphylococcus coagulase-negativa, particularmente, os Staphylococcus epidermidis são a causa mais freqüente de infecções relacionadas ao cateter por sua habilidade em aderir a uma superfície e entre si (aderência intercelular) formando biofilme em multicamadas sobre superfícies de polímeros. O objetivo do presente estudo foi avaliar cepas hospitalares de Staphylococcus coagulasenegativa isoladas de cateteres intravenosos, quanto à resistência a oxacilina, produção de slime, aderência ao poliestireno, habilidade de formar biofilme sobre superfícies abióticas (cateter esterilizado) e a presença de genes icaAD. Na presente pesquisa, a presença de icaA e icaD foi determinada pelo método PCR, em uma coleção de 27 amostras Staphylococcus coagulase-negativa (10 Staphylococcus epidermidis, 4 S. haemolyticus, 2 S. hominis, 2 S. lugdunensis, 1 S. saprophyticus, 1 S. schleiferi, 2 S. xylosus e 4 S. warneri). Os genes icaAD foram detectados em dez cepas S. epidermidis... (Resumo completo, clicar acesso eletrônmico abaixo) / Abstract: Coagulase-negative Staphylococcus, particularly, Staphylococcus epidermidis are frequent cause of infections associated with catheters and is attributed to the attachment ability on a surface and each other (intercellular adhesion) forming a multilayered biofilm on polymeric surfaces. The objective of the present study was to evaluate coagulase-negative Staphylococcus strains isolated from intravenous catheters by oxacillin resistance, slime production (qualitative method) and spectrophotometric assay (quantitative method), ability to form biofilm on abiotic surfaces (steriled catheter) and the presence of icaAD genes. In the present study icaA and icaD were determined by PCR method, in a collection of 27 coagulasenegative Staphylococcus (10 Staphylococcus epidermidis, 4 S. haemolyticus, 2 S. hominis, 2 S. lugdunensis, 1 S. saprophyticus, 1 S. schleiferi, 2 S. xylosus and 4 S. warneri). The icaA genes were detected in nine S. epidermidis and icaD in ten. The slime-producing ability was determined by culture on Congo red agar plates in which slime-producing strains formed black colonies in 10 S. epidermidis, 4 S.haemolyticus, 4 S. warneri, 2 S. xylosus and 1 S. chromogenes, while nonslimeformingones develop red colonies. The quantitative assay of coagulase-negative Staphylococcus was observed in 19 strains, including: 10 S. epidermidis, 3 S.haemolyticus, 3 S. warneri, 2 S. xylosus, 1 S. chromogenes. The ability of coagulasenegative Staphylococcus to form biofilm embedded in an amorphous substance wasobserved by scanning electronic microscope on abiotic surface in 10 S. epidermidis,3 S. haemolyticus, 2 S. hominis, 2 S. lugdunensis, 1 S. saprophyticus, 1 S. schleiferi,2 S. xylosus and 3 S. warneri. The oxacillin resistance was observed in 9 strains S.epidermidis, 3 S. haemolyticus, 3 S. warneri, 1 S. xylosus and 1 S. chromogenes. All strains of staphylococci were susceptible... (Complete abstract, click eletronic address below) / Doutor
457

Adult age differences in the effect of positive and negative mood on memory for pleasant and unpleasant daily events

Davidson, Heather Anne 15 June 2018 (has links)
This study examined the influence of experimentally induced mood change on the learning and recall of a list of pleasant and unpleasant daily events in young (18-35 years) and old (58-75 years) women. Mild mood changes were induced by having 166 subjects read emotionally descriptive accounts of tragic or uplifting life experiences. For half the subjects, the mood induction was presented before they learned a list describing 15 pleasant and 15 unpleasant daily events. For the remaining subjects, the mood induction occurred before they recalled the list. Baseline memory performance was assessed by having all subjects learn and recall one list in a neutral mood. Two dependent variables were used to look at mood induced changes in level (Total recall) and content (Affective Bias = Pleasant Events - Unpleasant events) of memory recall. Only the 128 subjects who met prespecified criteria for mood change were used in these analyses. Compared to performance in the neutral mood condition, significant mood content effects were observed only for negative moods induced at time of recall. Equivalent changes in affective bias were found across age groups, however, were due to increased recall of mood congruent memory items for the young, and decreased recall of mood incongruent memory items for the old. This mood content effect contributed to an overall decrease in total recall for old participants that was not found for young subjects. Because significant group differences in baseline memory performance were found between and within age groups, analysis of covariance was employed, using baseline memory performance as a covariate. No differences in the pattern of significant effects were found. Similarly, the use of pre-experimental mood, verbal ability, and affective response to the memory stimuli as covariates did not change the results, suggesting observed age differences in mood-induced memory change could not be attributed to these factors. These findings suggest that the locus of mood congruent memory selectivity occurs at time of retrieval. Mood-related memory cuing appears to be equally effective for young and old. The observed qualitative age differences in mood congruent memory were the reverse of the predicted pattern, however, it was suggested that more effective use of mood control strategies by the older women could have produced these effects. Results also suggest that the elderly may be more sensitive to the disruptive effects of negative mood on memory processing / Graduate
458

The excess of automatic refraction over subjective refraction: dependence on age

Joubert, Leoni 12 September 2012 (has links)
M.Phil. / Using newly developed statistical analysis methods for refractive error this study examines the difference between autorefraction and subjective refraction and how it is related to age. The term autorefractive excess refers to the amount obtained by subtracting the subjective refraction from the autorefraction. The clinical sample consisted of five groups of fifty subjects each. The subjects in group 1 ranged in age from 1 to 10 years, group 2 from 11 to 20 years, group 3 from 21 to 30 years, group 4 from 31 to 40 years and group 5 from 41 years and older. Only one examiner (the author) and one autorefractor (Allergan-Humphrey 580) were used. The study found that there was a difference between the mean autorefractive excesses for the different age groups and that the difference between autorefraction and subjective refraction was statistically significant in both the left and the right eyes of all age groups. Left and right eyes exhibited similar behavior. The autorefractive excess for both the left and the right eyes together of group 1 was approximately -0.25/-0.18 x180 in conventional and (-0.25 0.00 -0.43)' in h-notation. The autorefractive excess increases by approximately (0.10 0.00 0.10)' per decade. There is an astigmatic component of approximately -0.18 x180 in both eyes of all age groups. Approximately 60% of the subjects had sphere-equivalent strengths of autorefractive excesses of under 0.50 D. Therefore 60% of subjects might be content with a prescription given from the autorefractor reading. Approximately 50% of subjects had cylinderequivalent strengths of autorefractive excesses of under 0.50 D.
459

Refractive status of children : intra-ocular variation and inter-ocular spread

Richter, Susarah Maria 22 September 2015 (has links)
M.Phil. / The aim of this study was to use auto refraction to investigate both the short-term intra-ocular variation of refractive status among primary school children and the spread of refractive status across eyes. The sample consisted of 90 Caucasian school children from a primary school in a small town, Eloff, in the Mpumalanga province of South Africa ...
460

Interplay between 2-oxoglutarate oxygenases and cancer : studies on the aspartyl/asparaginyl-β-hydroxylase

Pfeffer, Inga January 2014 (has links)
No description available.

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