1,229 research outputs found
The Effect of Achievement Goals on Self-Explanation and Transfer: Investigating the Role of Motivation on Learning
The role of student motivation in learning is an important issue for research to address, both for theoretical and practical purposes. The present research study tested a hypothesized behavioral pathway for previously documented benefits of student motivation – in particular, mastery-approach achievement goals – on learning and transfer (Belenky & Nokes-Malach, 2012). Achievement goals are the reasons students have for engaging in academic settings, such as wanting to develop their competence (mastery-approach goal), wanting to do better than their peers (performance-approach goal), or not wanting to do any worse than their peers (performance-avoidance goal). The present study manipulated achievement goals (mastery-approach, performance-approach, or performance-avoidance) that participants adopted while learning, and subsequently being tested on, basic statistical knowledge and procedures. It was predicted that mastery-approach goals would lead to higher levels of knowledge transfer. Additionally, talk aloud protocols were collected and coded to test hypothesis that mastery-approach goals would lead to more constructive learning processes, such as self-explanation. Finally, it was expected that the degree of self-explanations a student engaged in would be predictive of transfer. These hypotheses were not supported. Contrary to expectations, the performance-avoidance condition produced higher levels of transfer than the mastery-approach condition. Additionally, there were no differences between conditions in the amount of self-explanations generated. The amount of self-explanations was itself not predictive of transfer. These results are discussed in terms of possible ways the methodology may have reduced the difficulty of transfer, as well as what the results may mean for achievement goal theory, more broadly
Positive exchange bias in ferromagnetic La0.67Sr0.33MnO3 / SrRuO3 bilayers
Epitaxial La0.67Sr0.33MnO3 (LSMO)/ SrRuO3 (SRO) ferromagnetic bilayers have
been grown on (001) SrTiO3 (STO) substrates by pulsed laser deposition with
atomic layer control. We observe a shift in the magnetic hysteresis loop of the
LSMO layer in the same direction as the applied biasing field (positive
exchange bias). The effect is not present above the Curie temperature of the
SRO layer (), and its magnitude increases rapidly as the temperature is lowered
below . The direction of the shift is consistent with an antiferromagnetic
exchange coupling between the ferromagnetic LSMO layer and the ferromagnetic
SRO layer. We propose that atomic layer charge transfer modifies the electronic
state at the interface, resulting in the observed antiferromagnetic interfacial
exchange coupling.Comment: accepted to Applied Physics Letter
Evaluating Use of Custom Survey Reports by Local Health Departments
This report demonstrates how providing survey feedback, like comparative reports, to survey respondents can result in improvement activities. For each of the past three years (2010-2013), the North Carolina Institute for Public Health (NCIPH) has invited local health departments (LHDs) from 40 states to participate in a preparedness capacities survey. In addition, NCIPH fielded a six-question evaluation survey to a subset of LHDs (n=70) to determine how LHDs use these reports. LHDs that reported using their custom reports compared their preparedness capacities to other LHDs, conducted strategic planning (e.g., benchmarking, setting preparedness goals), planned staff trainings, and disseminated the report both internally and to external preparedness partners. Through evaluation of custom report use, we have found that survey feedback is a valuable part of a participatory research approach that promotes and encourages discussion, motivates improvement, and provides opportunities to identify potential solutions relevant to both researchers and LHDs
Nrt1 and Tna1-Independent Export of NAD+ Precursor Vitamins Promotes NAD+ Homeostasis and Allows Engineering of Vitamin Production
NAD+ is both a co-enzyme for hydride transfer enzymes and a
substrate of sirtuins and other NAD+ consuming enzymes.
NAD+ biosynthesis is required for two different regimens
that extend lifespan in yeast. NAD+ is synthesized from
tryptophan and the three vitamin precursors of NAD+: nicotinic
acid, nicotinamide and nicotinamide riboside. Supplementation of yeast cells
with NAD+ precursors increases intracellular
NAD+ levels and extends replicative lifespan. Here we show
that both nicotinamide riboside and nicotinic acid are not only vitamins but are
also exported metabolites. We found that the deletion of the nicotinamide
riboside transporter, Nrt1, leads to increased export of nicotinamide riboside.
This discovery was exploited to engineer a strain to produce high levels of
extracellular nicotinamide riboside, which was recovered in purified form. We
further demonstrate that extracellular nicotinamide is readily converted to
extracellular nicotinic acid in a manner that requires intracellular
nicotinamidase activity. Like nicotinamide riboside, export of nicotinic acid is
elevated by the deletion of the nicotinic acid transporter, Tna1. The data
indicate that NAD+ metabolism has a critical extracellular
element in the yeast system and suggest that cells regulate intracellular
NAD+ metabolism by balancing import and export of
NAD+ precursor vitamins
Negotiating professional and social voices in research principles and practice
This paper draws on work conducted for a qualitative interview based study which explores the gendered racialised and professional identifications of health and social care professionals. Participants for the project were drawn from the professional executive committees of recently formed Primary Care Trusts. The paper discusses how the feminist psychosocial methodological approach developed for the project is theoretically, practically and ethically useful in exploring the voices of those in positions of relative power in relation to both health and social care services and the social relations of gender and ethnicity. The approach draws on psychodynamic accounts of (defended) subjectivity and the feminist work of Carol Gilligan on a voice-centred relational methodology. Coupling the feminist with the psychosocial facilitates an emphasis on voice and dialogic communication between participant and researcher not always captured in psychosocial approaches which tend towards favouring the interviewer as ‘good listener’. This emphasis on dialogue is important in research contexts where prior and ongoing relationships with professional participants make it difficult and indeed undesirable for researchers to maintain silence
Decoherence and energy loss in QCD cascades in nuclear collisions
The medium modifications in the properties of QCD cascades are considered. In
particular, the changes in the intrajet rapidity distributions due to
medium-induced decoherence, collisional losses of cascade gluons and those of
final prehadrons are analyzed
Gell-Mann--Okubo Mass Formula for an SU(4) Meson Hexadecuplet
Using a linear mass spectrum of an meson hexadecuplet, we derive the
Gell-Mann--Okubo mass formula for the charmed mesons, in good agreement with
experiment. Possible generalization of this method to a higher symmetry group
is briefly discussed.Comment: 11 pages, LaTe
Coinfection With Influenza A Virus and Klebsiella oxytoca: An Underrecognized Impact on Host Resistance and Tolerance to Pulmonary Infections
Pneumonia is a world health problem and a leading cause of death, particularly affecting children and the elderly (1, 2). Bacterial pneumonia following infection with influenza A virus (IAV) is associated with increased morbidity and mortality but the mechanisms behind this phenomenon are not yet well-defined (3). Host resistance and tolerance are two processes essential for host survival during infection. Resistance is the host's ability to clear a pathogen while tolerance is the host's ability to overcome the impact of the pathogen as well as the host response to infection (4–8). Some studies have shown that IAV infection suppresses the immune response, leading to overwhelming bacterial loads (9–13). Other studies have shown that some IAV/bacterial coinfections cause alterations in tolerance mechanisms such as tissue resilience (14–16). In a recent analysis of nasopharyngeal swabs from patients hospitalized during the 2013–2014 influenza season, we have found that a significant proportion of IAV-infected patients were also colonized with Klebsiella oxytoca, a gram-negative bacteria known to be an opportunistic pathogen in a variety of diseases (17). Mice that were infected with K. oxytoca following IAV infection demonstrated decreased survival and significant weight loss when compared to mice infected with either single pathogen. Using this model, we found that IAV/K. oxytoca coinfection of the lung is characterized by an exaggerated inflammatory immune response. We observed early inflammatory cytokine and chemokine production, which in turn resulted in massive infiltration of neutrophils and inflammatory monocytes. Despite this swift response, the pulmonary pathogen burden in coinfected mice was similar to singly-infected animals, albeit with a slight delay in bacterial clearance. In addition, during coinfection we observed a shift in pulmonary macrophages toward an inflammatory and away from a tissue reparative phenotype. Interestingly, there was only a small increase in tissue damage in coinfected lungs as compared to either single infection. Our results indicate that during pulmonary coinfection a combination of seemingly modest defects in both host resistance and tolerance may act synergistically to cause worsened outcomes for the host. Given the prevalence of K. oxytoca detected in human IAV patients, these dysfunctional tolerance and resistance mechanisms may play an important role in the response of patients to IAV
Gender, age and the MBA: An analysis of extrinsic and intrinsic career benefits
Against the background of an earlier UK study, this paper presents the findings of a Canadian based survey of career benefits from the MBA. Results indicate firstly that gender and age interact to influence perceptions of career outcomes (young men gain most in terms of extrinsic benefits of career change and pay), and secondly that both men and women gain intrinsic benefits from the MBA. However, intrinsic benefits vary by gender: men in the study were more likely to say they gained confidence from having a fuller skill set while women were more likely to say they gained confidence from feelings of self worth; men emphasised how they had learned to give up control while women argued that they had gained a ‘voice’ in the organization. The role of the MBA in career self- management and the acquisition of key skills are examined as well as the implications for the design of programmes in meeting the varied need of men and women in different age groups
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