834 resultados para limitations of therapy
Resumo:
Three sibling species of shrews, the common shrew (Sorex araneus), the Valais shrew (S. antinorii) and the Jersey shrew (S. coronatus) are morphologically similar. Different techniques based on karyorypes, morphology, biochemistry and genetic markers have been developed to identify individuals from these taxa. In this paper, we have used multiple microsatellite markers (L13, L14 and L99) to identify 55 dead animals coming from the Tarentaise Valley in France. As some individuals showed an unclear pattern with loci previously thought to be diagnostic (Lugon-Moulin et al. 2000), we have used morphologic measurements (Hausser et al. 1991) to confirm the status of these animals. This analysis clearly showed the limitations of the use of genetic diagnostic markers that have been designed in local populations and then applied to a wider scale. Even if these markers have great advantages over other techniques (i.e. simple to use and do not require samples from living animals), they should always be used with caution. There is always a risk of a locus not being diagnostic in the sampling region or in finding individuals with hybrid genotypes. Additional genetic markers should then be used, simultaneously with other identification techniques, to be sure of the status of the individuals.
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When a bloodstream infection (BSI) is suspected, most of the laboratory results-biochemical and haematologic-are available within the first hours after hospital admission of the patient. This is not the case for diagnostic microbiology, which generally takes a longer time because blood culture, which is to date the reference standard for the documentation of the BSI microbial agents, relies on bacterial or fungal growth. The microbial diagnosis of BSI directly from blood has been proposed to speed the determination of the etiological agent but was limited by the very low number of circulating microbes during these paucibacterial infections. Thanks to recent advances in molecular biology, including the improvement of nucleic acid extraction and amplification, several PCR-based methods for the diagnosis of BSI directly from whole blood have emerged. In the present review, we discuss the advantages and limitations of these new molecular approaches, which at best complement the culture-based diagnosis of BSI.
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The paper concentrates on trust as a research topic that receives increasing attention from the side of different social disciplines. The author of this thesis attempts to identify the reasons of this phenomenon, as well as the decline in usage of the concepts conveying a congenial idea, such as, solidarity, cooperation, social cohesion, social capital or connectedness. The key hypotheses, such as paradigmatic change within the social sciences, emergence of risk society, proliferation of the postmodem condition, new infonnation and communication technologies and the crisis of democracy are considered through the works of the authors who now mainly responsible for the shaping of the discourse of trust. The concepts of Luhmann, Putnam, Sztompka, Fukuyama and Hardin are analyzed from an epistemological viewpoint in its ontological and political implications. The primary goal of the paper is to overview trust from the methodological viewpoint, illustrating the limitations of the concept as a research strategy as weII as it advantages in the epoch when the social sciences acquire a status of moral disciplines.
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The purpose ofthis study was to investigate the emotion assumptions underlying just-world theory. This theory proposes that people have a need to believe in a just world - a world where people get what they deserve. The first emotion assumption is that people, therefore, find injustices (Le., undeserved outcomes) threatening and thus emotionally arousing. Second, it is this arousal that is assumed to drive subsequent strategies for maintaining the belief in a just world. One strategy an individual may use to maintain this belief is derogating victims of injustice, or seeing their character in a more negative light. To test these two assumptions, 102 participants viewed a video depicting either a victim who presumably presented a high threat to people's belief in ajust world (she was innocent and, therefore, undeserving of her fate) or low threat (she was not innocent and, therefore, more deserving of her fate) while their heart rate and EDA was measured. Half of the participants were then given the opportunity to help the victim whereas the other half were not given this opportunity. The manipulations were followed by both explicit and indirect measures of evaluations ofthe victim as well as self-report measures of affect experienced while watching the victim video, and an individual difference scale assessing the strength of participants' just-world beliefs (as well as other measures that were part ofa larger study). Results indicated that participants did report feeling more threatened by the innocent victim. Although there was some evidence of victim derogation on the implicit measure of victim evaluation, there was no evidence that emotional arousal drove the negative evaluations of the victim who could not be helped. Some interaction effects with individual differences in just-world beliefs did occur, but these were not entirely consistent with the rationale behind the individual difference scales. These results provide only weak support for the first emotion assumption ofjust-world theory. Implications of these findings as well as limitations of the study and future directions concerning just-world theory are discussed.
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The purpose of this exploratory investigation was to provide a more precise understanding and basis from which to assess the potential role of the precautionary principle in tourism. The precautionary principle, analogous to the ideal of sustainable development, is a future-focused planning and regulatory mechanism that emphasizes pro-action and recognizes the limitations of contemporary scientific methods. A total of 100 respondents (80 tourism academics, 20 regional government tourism officials) from Canada, United States, United Kingdom, Australia and New Zealand completed the webbased survey between May and June 2003. Respondents reported their understanding of the precautionary principle, rated stakeholder involvement and education strategies, assessed potential barriers in implementation, and appraised steps of a proposed fi-amework for implementation. Due to low sub sample numbers, measures of central tendency were primarily used to compare groups, while inferential statistics were applied when warranted. Results indicated that most respondents (79%) felt the principle could be a guiding principle for tourism, while local and regional government entities were reported to have the most power in the implementation process. Findings suggested close links between the precautionary principle and sustainability, as concern for future generations was the most critical element of the principle for tourism. Overall, tourism academics were more supportive of the precautionary principle in tourism than were regional government tourism officials. Only minor variation was found in responses among regional groups across all variables. This study established basic ground for understanding the precautionary principle in tourism and has been effective in formulating more precise questions for future research.
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ABSTRACT Recombinant adenoviruses are currently under intense investigation as potential gene delivery and gene expression vectors with applications in human and veterinary medicine. As part of our efforts to develop a bovine adenovirus type 2 (BAV2) based vector system, the nucleotide sequence of BAV2 was determined. Sixty-six open reading frames (ORFs) were found with the potential to encode polypeptides that were at least 50 amino acid (aa) residue long. Thirty-one of the BAV2 polypeptide sequences were found to share homology to already identified adenovirus proteins. The arrangement of the genes revealed that the BAV2 genomic organization closely resembles that of well-characterized human adenoviruses. In the course of this study, continuous propagation of BAV2 over many generations in cell culture resulted in the isolation of a BAV2 spontaneous mutant in which the E3 region was deleted. Restriction enzyme, sequencing and PCR analyses produced concordant results that precisely located the deletion and revealed that its size was exactly 1299 bp. The E3-deleted virus was plaque-purified and further propagated in cell culture. It appeared that the replication of such a virus lacking a portion of the E3 region was not affected, at least in cell culture. Attempts to rescue a recombinant BAV2 virus with the bacterial kanamycin resistance gene in the E3 region yielded a candidate as verified with extensive Southern blotting and PCR analyses. Attempts to purify the recombinant virus were not successful, suggesting that such recombinant BAV2 was helper-dependent. Ten clones containing full-length BAV2 genomes in a pWE15 cosmid vector were constructed. The infectivity of these constructs was tested by using different transfection methods. The BAV2 genomic clones did appear to be infectious only after extended incubation period. This may be due to limitations of various transfection methods tested, or biological differences between virus- and E. co//-derived BAV2 DNA.
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This qualitative study investigated how a team of 7 hospital educators collaborated to develop e-curriculum units to pilot for a newly acquired learning -r management system at a large, multisite academic health sciences centre. A case study approach was used to examine how the e-Curriculum Team was structured, how the educators worked together to develop strategies to better utilize e-leaming in their ovwi practice, what e-curriculum they chose to develop, and how they determined their priorities for e-curriculum development. It also inquired into how they planned to involve other educators in using e-leaming. One set of semistructured interviews with the 6 hospital educators involved in the project, as well as minutes of team meetings and the researcher's journal, were analyzed (the researcher was also a hospital educator on the team). Project management structure, educator support, and organizational pressures on the implementation project feature prominently in the case study. This study suggests that implementation of e-leaming will be more successful if (a) educators involved in the development of e-leaming curriculum are supported in their role as change agents, (b) the pain of vmleaming current educational practice is considered, (c) the limitations of the software being implemented are recognized, (d) time is spent leaming about best practice, and (e) the project is protected as much as possible from organizational pressures and distractions.
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Health education is essential to the successful treatment of individuals with chronic illnesses. Self-management is a philosophical model of health education that has been shown to be effective in teaching individuals with chronic arthritis to manage their illness as part of their daily lives. Despite the proven results of arthritis self-management programs, some limitations of this form of health education were apparent in the literature. The present study attempted to address the problems of the self-management approach of health education such as reasons for lack of participation in programs and poor course outcomes. In addition, the study served to investigate the relationship between course outcomes and participation in programs with the theory upon which arthritis self-management programs are based, known as self-efficacy theory. Through a combination of qualitative and quantitative methodologies, data collection, and analysis, a deeper understanding of the self-management phenomenon in the treatment of chronic arthritic conditions was established. Findings of the study confirm findings of previous studies that suggest that arthritis self-management programs result in enhanced levels of self-efficacy and are effective in teaching individuals with arthritis to self-manage their health and health care. Findings of the study suggest that there are many factors that determine the choice of participants to participate in programs and the outcomes for the individuals who do choose to participate in programs. Some of the major determinants of enrollment and outcomes of programs include: the participant's personality, beliefs, attitudes and abilities, and the degree of emotional acceptance of the illness. Other determinants of course enrollment and outcomes included class size and length of time, timing of participation, and ongoing support after the program. The results of the study are consistent with the self-management literature and confirm the relationship between the underlying philosophies of adult education and Freire's model of education and self-management.
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The development, assessment, and implementation of a program evaluation instrument was carried out to evaluate the impact and efficacy of the EMPOWER Program. This intervention was created to educate residents at a shelter for abused women with an anticipated outcome of prevention. Participants included the staff and residents at 2 shelters in Southern Ontario. Client pre, post and follow-up measures were obtained and analyzed statistically and using keyword content analysis. A single staff measure was obtained and summarized using keyword content analysis. Qualitative results were suggestive of important change in participants. All women in the post and follow-up measures believed their participation in the EMPOWER Program provided them with the knowledge, skills, and confidence to avoid abusive relationships in the fliture. This transformational impact was repeatedly expressed in both resident and staff feedback. Limitations of this research, as well as suggestions for future study were discussed.
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The present study has both theoretical and practical aspects. The theoretical intent of the study was to closely examine the relationship between muscle activity (EMG) and EEG state during the process of falling asleep. Sleep stages during sleep onset (SO) have been generally defined with regards to brain wave activity (Recht schaff en & Kales (1968); and more precisely by Hori, Hayashi, & Morikawa (1994)). However, no previous study has attempted to quantify the changes in muscle activity during this same process. The practical aspect of the study examined the reliability ofa commercially developed wrist-worn alerting device (NovAlert™) that utilizes changes in muscle activity/tension in order to alert its user in the event that he/she experiences reduced wakefulness that may result in dangerous consequences. Twelve female participants (aged 18-42) sp-ent three consecutive nights in the sleep lab ("Adaptation", "EMG", and "NOVA" nights). Each night participants were given 5, twenty-minute nap opportunities. On the EMG night, participants were allowed to fall asleep freely. On the NOV A night, participants wore the Nov Alert™ wrist device that administered a Psychomotor Vigilance Test (PVT) when it detected that muscle activity levels had dropped below baseline. Nap sessions were scored using Hori's 9-stage scoring system (Hori et aI, 1994). Power spectral analyses (FFT) were also performed. Effects ofthe PVT administration on EMG and EEG frequencies were also examined. Both chin and wrist EMG activity showed reliable and significant decline during the early stages ofHori staging (stages HO to H3 characterized by decreases in alpha activity). All frequency bands studied went through significant changes as the participants progressed through each ofHori's 9 SO stages. Delta, theta, and sigma activity increased later in the SO continuum while a clear alpha dominance shift was noted as alpha activity shifted from the posterior regions of the brain (during Hori stages HO to H3) to the anterior portions (during Hori stages H7 to H9). Administration of the PVT produced significant increases in EMG activity and was effective in reversing subjective drowsiness experienced during the later stages of sleep onset. Limitations of the alerting effects of the PVTs were evident following 60 to 75 minutes of use in that PVTs delivered afterwards were no longer able to significantly increase EMG levels. The present study provides a clearer picture of the changes in EMG and EEG during the sleep onset period while testing the efficacy of a commercially developed alerting device. EMG decreases were found to begin during Hori stage 0 when EEG was - dominated by alpha wave activity and were maximal as Hori stages 2 to 5 were traversed (coincident with alpha and beta activity). This signifies that EMG decrements and the loss of resting alpha activity are closely related. Since decreased alpha has long been associated with drowsiness and impending sleep, this investigation links drops in muscle tone with sleepiness more directly than in previous investigations. The EMG changes were reliably demonstrated across participants and the NovAlert™ detected the EMG decrements when Hori stage 3 was entered. The alerting vibrations produced by the NovAlert™ occurred early enough in the SO process to be of practical importance as a sleepiness monitoring and alerting device.
Resumo:
BACKGROUND: Dyslipidemia is recognized as a major cause of coronary heart disease (CHD). Emerged evidence suggests that the combination of triglycerides (TG) and waist circumference can be used to predict the risk of CHD. However, considering the known limitations of TG, non-high-density lipoprotein (non-HDL = Total cholesterol - HDL cholesterol) cholesterol and waist circumference model may be a better predictor of CHD. PURPOSE: The Framingham Offspring Study data were used to determine if combined non-HDL cholesterol and waist circumference is equivalent to or better than TG and waist circumference (hypertriglyceridemic waist phenotype) in predicting risk of CHD. METHODS: A total of3,196 individuals from Framingham Offspring Study, aged ~ 40 years old, who fasted overnight for ~ 9 hours, and had no missing information on nonHDL cholesterol, TG levels, and waist circumference measurements, were included in the analysis. Receiver Operator Characteristic Curve (ROC) Area Under the Curve (AUC) was used to compare the predictive ability of non-HDL cholesterol and waist circumference and TG and waist circumference. Cox proportional-hazards models were used to examine the association between the joint distributions of non-HDL cholesterol, waist circumference, and non-fatal CHD; TG, waist circumference, and non-fatal CHD; and the joint distribution of non-HDL cholesterol and TG by waist circumference strata, after adjusting for age, gender, smoking, alcohol consumption, diabetes, and hypertension status. RESULTS: The ROC AUC associated with non-HDL cholesterol and waist circumference and TG and waist circumference are 0.6428 (CI: 0.6183, 0.6673) and 0.6299 (CI: 0.6049, 0.6548) respectively. The difference in the ROC AVC is 1.29%. The p-value testing if the difference in the ROC AVCs between the two models is zero is 0.10. There was a strong positive association between non-HDL cholesterol and the risk for non-fatal CHD within each TO levels than that for TO levels within each level of nonHDL cholesterol, especially in individuals with high waist circumference status. CONCLUSION: The results suggest that the model including non-HDL cholesterol and waist circumference may be superior at predicting CHD compared to the model including TO and waist circumference.
Resumo:
Background. West Nile Virus (WNV), a mosquito-borne flavivirus, is one of an increasing number of infectious diseases that have been emerging or re-emerging in the last two decades. Since the arrival ofWNV to Canada to present date, the Niagara Region has only reported 30 clinical cases, a small number compared to the hundreds reported in other regions of similar conditions. Moreover, the last reported human case in Niagara was in 2006. As it has been demonstrated that the majority of WNV infections are asymptomatic, the question remains whether the lack of clinical cases in Niagara truly reflects the lack of transmission to humans or if infections are still occurring but are mostly asymptomatic. Objectives. The general objective of this study was to establish whether or not active WNV transmission could be detected in a human population residing in Niagara for the 2007 transmission season. To fullfil this objective, a cross-sectional seroprevalence study was designed to investigate for the presence of anti-WNV antibodies in a sample of Mexican migrant agricultural workers employed in farms registered with the Seasonal Agricultural Workers Program (SAWP). Due to the Mexican origin of the study participants, three specific research objectives were proposed: a) determine the seroprevalence ofanti-WNV antibodies as well as anti-Dengue virus antibodies (a closely related virus prevalent in Mexico and likely to confound WNV serology); b) analyze risk factors associated with WNV and Dengue virus seropositivity; and c) assess the awareness of study participants about WNV infection as well as their understanding of the mode of transmission and clinical importance of the infection. Methodology: After obtaining ethics clearance from Brock University, farms were visited and workers invited to participate. Due to time constraints, only a small number of farms were enrolled with a resulting convenience and non-randomized study sample. Workers' demographic and epidemiological data were collected using a standardized questionnaire and blood samples were drawn to determine serum anti-WNV and anti- Dengue antibodies with a commercial ELISA. All positive samples were sent to the National Microbiology Laboratory in Winnipeg, Manitoba for confirmation with the Plaque Reduction Neutralization Test (PRNT). Data was analyzed with Stata 10.0. Antibody determinations were reported as seroprevalence proportions for both WNV and Dengue. Logistic regression was used to analyze risk factors that may be associated with seropositivity and awareness was reported as a proportion of the number of individuals possessing awareness over the total number of participants. Results and Discussion. In total 92 participants working in 5 farms completed the study. Using the commercial ELISA, seropositivity was as follows: 2.2% for WNV IgM, 20.7% for WNV IgG, and 17.1 % for Dengue IgG. Possible cross-reactivity was demonstrated in 15/20 (75.0%) samples that were positive for both WNV IgG and Dengue IgG. Confirmatory testing with the PRNT demonstrated that none of the WNV ELISA positive samples had antibodies to WNV but 13 samples tested positive for anti-Dengue antibodies (14.1 % Dengue sereoprevalence). The findings showed that the ELISA performance was very poor for assessing anti-WNV antibodies in individuals previously exposed to Dengue virus. However, the ELISA had better sensitivity and specificity for assessing anti-Dengue antibodies. Whereas statistical analysis could not be done for WNV seropositivity, as all samples were PRNT negative, logistic regression demonstrated several risk factors for Dengue exposure_ The first year coming to Canada appeared to be significantly associated with increased exposure to Dengue while lower socio-economic housing and the presence of a water basin in the yard in Mexico appeared to be significantly associated with a decreased exposure to Dengue_ These seemingly contradictory results illustrate that in mobile populations such as migrant workers, risk factors for exposure to Dengue are not easily identified and more research is needed. Assessing the awareness of WNV and its clinical importance showed that only 23% of participants had some knowledge of WNV, of which 76% knew that the infection was mosquito-borne and 47% recognized fever as a symptom. The identified lack of understanding and awareness was not surprising since WNV is not a visible disease in Mexico. Since WNV persists in an enzootic cycle in Niagara and the occurrence of future outbreaks is unpredictable, the agricultural workers remain at risk for transmission. Therefore it important they receive sufficient health education regarding WNV before leaving Mexico and during their stay in Canada. Conclusions. Human transmission of WNV could not be proven among the study participants even when due to their occupation they are at high risk for mosquito bites. The limitations of the study sample do not permit generalizable conclusions, however, the study findings are consistent with the absence of clinical cases in the Niagara Region, so it is likely that human transmission is indeed neglible or absent. As evidenced by our WNV serology results, PRNT must be utilized as a confirmatory test since false positivity occurs frequently. This is especially true when previous exposure to Dengue virus is likely.
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The present thesis outlines our latest findings on the reactivity of the Burgess reagent with oxiranes. Structural, mechanistic, and computational studies are presented. Included is the development of a (-)-menthyl version of the Burgess reagent and its application to the synthesis of enantiomerically pure ~-amino alcohols. This methodology has been exploited in the formal enantiodivergent synthesis of the (+)- and (-)-isomers of balanol. Also described is a second generation approach to both balanol enantiomers; each commencmg with the chemoenzymatic dihydroxylation of bromobenzene. This study also describes the steric and functional limitations of the toluene dioxygenase-mediated oxidation of benzoate esters. The metabolite derived from ethyl benzoate was employed in a formal synthesis of oseltamivir. Finally, several synthetic approaches to oseltamivir and its analogs are presented, each proceeding through a different vinyl aziridine derived from bromobenzene and ethyl benzoate.
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As identified in the literature, a lack of understanding of the functional properties and triggers of stereotypic behaviour exists. When looking at this behaviour from an Applied Behaviour Analysis (ABA) framework, limitations are evident around identifying specific sensory modalities and functional properties of such behaviour. Antecedents particularly are difficult to identify and interpret. Therefore an interdisciplinary approach to assessment using two types of professional services commonly received by individuals with autism was proposed. However before this approach could be investigated the current interpretations of Stereo typic behaviour by each professional must be examined along with perceptions of interdisciplinary collaboration. The purpose of this study was to use an in-depth qualitative analysis to reveal the interpretations of stereotypy and collaboration from the perspectives of two particular professionals. The results of the study demonstrated that occupational therapists and behaviour analysts likely have different interpretations of the same behaviour,that consultation is the common model used to interact with other disciplines, and that professionals may have mixed feelings toward interdisciplinary practices as an approach to stereotypic behaviour. Strengths and limitations of the study were highlighted along with specific directions for future research.
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Empirical research has consistently demonstrated a positive association between psychopathic traits and physical aggression (Campbell, Porter, & Santor, 2004; Gretton, Hare, & Catchpole, 2004; Raine et aI., 2006; Spain, Douglas, Poythress, & Epstein, 2004). Moreover, research has also found that the emotional/interpersonal (Factor 1) psychopathy traits tend to be more closely associated with goal oriented, proactive aggression, whereas the social deviance (Factor 2) psychopathy characteristics have been more closely linked to reactive aggression, which is perpetrated in response to threat or provocation (Flight & Forth, 2007). Blair (2004; 2005; 2006) has recently proposed the Integrated Emotions Systems Model (lES), which posits that the association between Factor 1 psychopathy traits and proactive aggression is due to amygdala dysfunction leading to failed moral socialization. Consequently, individuals who exhibit Factor 1 psychopathy traits do not experience affective empathy in response to distress cues exhibited by others, thus, preventing the inhibition of proactive aggression. The current investigation sought to test this model by examining the associations among the emotional/interpersonal (Factor 1) psychopathy traits, proactive aggression, and affective empathy. After accounting for head injury, Factor 2 psychopathy traits, reactive aggression, and cognitive empathy, it was hypothesized that 1) Factor 1 psychopathy traits would predict proactive aggression, and 2) that affective empathy is a common cause of Factor 1 psychopathy traits, proactive aggression, and of the relationship between these two constructs. This hypothesis assumed that (a) affective empathy would uniquely predict Factor 1 psychopathy traits, (b) that affective empathy would uniquely predict proactive aggression, and (c) that affective empathy would account for the relationship between Factor I psychopathy traits and proactive aggression. The total sample consisted of 137 male undergraduate students. Participants completed measures of psychopathy (SRP III; Paulhus, Hemphill, & Hare, in press), aggression (PCS; Marsee, Kimonis, & Frick, 2004; RPQ; Raine et at, 2006), dispositional cognitive and affective empathy (BES; Jolliffe & Farrington, 2006; TES; Spreng, McKinnon, Mar, & Levine, 2009), and situational cognitive and affective empathy in response to neutral and empathy eliciting video clips. Physiological indices (heart rate & electrodermal activity) of affective empathy were also obtained while participants viewed the neutral and empathy eliciting videos. Findings indicated that Factor I psychopathy traits predicted proactive aggression. In addition, results demonstrated that affective empathy predicted both Factor I psychopathy traits and proactive aggression. However, the association between affective empathy and proactive aggression appeared to be dependent on the conceptualization and measurement of affective empathy. Conversely, affective empathy did not appear to account for the relationship between Factor I psychopathy traits and proactive aggression. Overall, results demonstrated partial support for the IES model. Implications of the results, limitations of the study and future research directions are discussed.