977 resultados para SELF-CONSISTENT


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Microwave annealing is an emerging technique for achieving ordered patterns of block copolymer films on substrates. Little is understood about the mechanisms of microphase separation during the microwave annealing process and how it promotes the microphase separation of the blocks. Here, we use controlled power microwave irradiation in the presence of tetrahydrofuran (THF) solvent, to achieve lateral microphase separation in high- lamellar-forming poly(styrene-b-lactic acid) PS-b-PLA. A highly ordered line pattern was formed within seconds on silicon, germanium and silicon on insulator (SOI) substrates. In-situ temperature measurement of the silicon substrate coupled to condition changes during "solvo-microwave" annealing allowed understanding of the processes to be attained. Our results suggest that the substrate has little effect on the ordering process and is essentially microwave transparent but rather, it is direct heating of the polar THF molecules that causes microphase separation. It is postulated that the rapid interaction of THF with microwaves and the resultant temperature increase to 55 degrees C within seconds causes an increase of the vapor pressure of the solvent from 19.8 to 70 kPa. This enriched vapor environment increases the plasticity of both PS and PLA chains and leads to the fast self-assembly kinetics. Comparing the patterns formed on silicon, germanium and silicon on insulator (SOI) and also an in situ temperature measurement of silicon in the oven confirms the significance of the solvent over the role of substrate heating during "solvo-microwave" annealing. Besides the short annealing time which has technological importance, the coherence length is on a micron scale and dewetting is not observed after annealing. The etched pattern (PLA was removed by an Ar/O-2 reactive ion etch) was transferred to the underlying silicon substrate fabricating sub-20 nm silicon nanowires over large areas demonstrating that the morphology is consistent both across and through the film.

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All teachers participate in self-directed professional development (PD) at some point in their careers; however, the degree to which this participation takes place varies greatly from teacher to teacher and is influenced by the leadership of the school principal. The motivation behind why teachers choose to engage in PD is an important construct. Therefore, there is a need for better understanding of the leader’s role with respect to how and why teachers engage in self-directed professional development. The purpose of the research was to explore the elementary teachers’ motivation for and the school principal’s influence on their engagement in self-directed professional development. Three research questions guided this study: 1. What motivates teachers to engage in self-directed professional development? 2. What are the conditions necessary for promoting teachers’ engagement in self-directed professional development? 3. What are teachers’ perceptions of the principal’s role in supporting, fostering, encouraging, and sustaining the professional development of teachers? A qualitative research approach was adopted for this study. Six elementary teachers from one south-eastern Ontario school board, consisting of three novice and three more experienced teachers, provided their responses to a consistent complement of 14 questions. Their responses were documented via individual interviews, transcribed verbatim, and thematically analysed. The findings suggested that, coupled with the individual motivating influences, the culture of the school was found to be a conditional dynamic that either stimulated or dissuaded participation in self-directed PD. The school principal provided an additional catalyst or deterrence via relational disposition. When teachers felt their needs for competency, relatedness, and autonomy were satisfied, the conditions necessary to motivate teachers to engage in PD were fulfilled. A principal who personified the tenets of transformational leadership served to facilitate teachers’ inclinations to take on PD. A leadership style that was collaborative and trustful and allowed for personal autonomy was a dominant foundational piece that was critical for participant participation in self-directed PD. Finally, the principals were found to positively impact school climate by partaking in PD alongside teachers and ensuring there was a shared vision of the school so that teachers could tailor PD to parallel school interests.

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Self-report measures of cognitive problems may have value, but there are indications that scores on such measures are influenced by other factors such as personality. In an online correlational study, 523 non-clinical volunteers completed measures of personality, digit span, and the Prospective and Retrospective Memory Questionnaire. Self-reported prospective and retrospective memory failures were associated positively with neuroticism and negatively with conscientiousness, but not with digit span performance. These findings are consistent with other indications that conscientiousness and neuroticism may underpin self-reports of cognitive problems.

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LEÃO, Adriano de Castro; DÓRIA NETO, Adrião Duarte; SOUSA, Maria Bernardete Cordeiro de. New developmental stages for common marmosets (Callithrix jacchus) using mass and age variables obtained by K-means algorithm and self-organizing maps (SOM). Computers in Biology and Medicine, v. 39, p. 853-859, 2009

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LEÃO, Adriano de Castro; DÓRIA NETO, Adrião Duarte; SOUSA, Maria Bernardete Cordeiro de. New developmental stages for common marmosets (Callithrix jacchus) using mass and age variables obtained by K-means algorithm and self-organizing maps (SOM). Computers in Biology and Medicine, v. 39, p. 853-859, 2009

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In the present studies I investigated whether college students’ perceptions of effort source influenced their perceptions of the relation between levels of their own effort and ability in mathematics. In Study 1 (N = 210), I found using hypothetical vignettes that perceptions of task-elicited effort (i.e., effort that arises due to the subjective difficulty or ease of the task) led to perceptions of an inverse relation between one’s effort and ability, and perceptions of self-initiated effort (i.e., effort that arises due to one’s own motivation or lack of motivation) led to perceptions of a positive relation between one’s effort and ability, consistent with my hypotheses and prior research. In Study 2 (N = 160), participants completed an academic task and I used open-ended questions to manipulate their perceptions of effort source. I found that participants in the task-elicited condition endorsed no overall relation between effort and ability, and participants in the self-initiated condition endorsed an overall inverse relation, which is inconsistent with my hypotheses and prior research. Possible explanations for the findings, as well as broader theoretical and educational implications are discussed.

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Background To identify those characteristics of self-management interventions in patients with heart failure (HF) that are effective in influencing health-related quality of life, mortality, and hospitalizations. Methods and Results Randomized trials on self-management interventions conducted between January 1985 and June 2013 were identified and individual patient data were requested for meta-analysis. Generalized mixed effects models and Cox proportional hazard models including frailty terms were used to assess the relation between characteristics of interventions and health-related outcomes. Twenty randomized trials (5624 patients) were included. Longer intervention duration reduced mortality risk (hazard ratio 0.99, 95% confidence interval [CI] 0.97–0.999 per month increase in duration), risk of HF-related hospitalization (hazard ratio 0.98, 95% CI 0.96–0.99), and HF-related hospitalization at 6 months (risk ratio 0.96, 95% CI 0.92–0.995). Although results were not consistent across outcomes, interventions comprising standardized training of interventionists, peer contact, log keeping, or goal-setting skills appeared less effective than interventions without these characteristics. Conclusion No specific program characteristics were consistently associated with better effects of self-management interventions, but longer duration seemed to improve the effect of self-management interventions on several outcomes. Future research using factorial trial designs and process evaluations is needed to understand the working mechanism of specific program characteristics of self-management interventions in HF patients.

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There are several studies that suggest that different people deposit different quantities of their own DNA on items they touch, i.e. some are good shedders and others are bad shedders. It is of interest to determine if individuals deposit consistent quantities of their own DNA, no matter the occasion, as well as the degree of variability among individuals. To investigate this, participants were tested for their ability to deposit DNA by placing right and left handprints on separate DNA-free glass plates at three set times during the day (morning, midday and afternoon) on four different days spaced over several weeks. Information regarding recent activities performed by the individual was recorded, along with information on gender, hand dominance and hand size. A total of 240 handprint deposits were collected from 10 individuals and analyzed for differences in DNA quantity and the type of the DNA profile obtained at different times of the day, on different days, between the two hands of the same individual, and between different individuals. Furthermore, the correlation between the deposit quantity and the ratio of self to non-self DNA in the mixed deposits was analyzed to determine if the amount of non-self DNA has an effect on overall DNA quantities obtained. In general, this study has shown that while there is substantial variation in the quantities deposited by individuals on different occasions, some clear trends were evident with some individuals consistently depositing significantly more or less DNA than others. Non-self DNA was usually deposited along with self DNA and, in most instances, was the minor component. Incidents where the non-self portion was the major component were very rare and, when observed, were associated with a poor depositor/shedder. Forensic DNA scientists need to consider the range and variability of DNA a person deposits when touching an object, the likelihood of non-self DNA being co-deposited onto the handled object of interest and the factors that may affect the relative quantity of this component within the deposit.

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Teamwork is generally assessed either solely by academic staff or by both academic staff andstudents themselves confidentially as well as collaboratively. Peer- and self-assessments have beenused primarily to assess teamwork process and teacher assessment to assess teamwork product.Peer- and self-assessments are useful to elicit team members’ contribution towards teamwork and toconvert team mark into individual marks, provided the scores are reliable (the extent to which thescores are consistent). However, not all peer- and self-assessment scores are reliable. Anecdotal andliterature evidence suggest that there are several cases of inconsistencies in these scores. Individualcontribution scores given by teammates to an assessee (including himself/herself) can sometimesvary significantly due to both intentional and unintentional reasons. Simply using total individual ratingscores without considering an assessor’s reliability to estimate individual contribution factors cansometime results unfair grades and becomes hindrance to learning through teamwork.PURPOSEThis study proposes an extended approach to adjust inconsistent and/or distorted minority peer andself-assessment scores of teamwork using standard normal probability concept.APPROACHIn order to adjust inconsistent and/or distorted minority peer-and self-assessment scores of teamwork,an extended approach has been proposed. The approach uses the reliability of assessor’s scores ofan assessee using standard normal probability curve. The evaluation of the extended approach isconducted by comparing with the existing approaches using two case examples of peer- and selfassessmentof teamwork where minority team members’ scores are inconsistent.RESULTSThe evaluation of the extended approach shows that the proposed method is superior to the availableapproaches in order to adjust inconsistent peer- and self-assessment scores for special cases wherescores of minority team members are inconsistent. The extended approach helps both to automaticallydetect such scoring anomalies and to adjust the scores so that the fairer contributions to the teamworkwould be obtained and utilised.CONCLUSIONSThe extended approach is useful in that it helps both to automatically detect scoring anomalies and todevise the methods to adjust them. However, the approach does not address the issue of scoringinconsistencies by majority of team members as it uses average score as a basis for identifyinginconsistencies. Moreover, the approach needs to be implemented in the real teamwork environmentin order to identify the impacts of these scoring adjustments in teamwork process and teamworkproduct.

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This paper discusses a framework in which catalog service communities are built, linked for interaction, and constantly monitored and adapted over time. A catalog service community (represented as a peer node in a peer-to-peer network) in our system can be viewed as domain specific data integration mediators representing the domain knowledge and the registry information. The query routing among communities is performed to identify a set of data sources that are relevant to answering a given query. The system monitors the interactions between the communities to discover patterns that may lead to restructuring of the network (e.g., irrelevant peers removed, new relationships created, etc.).