1,170 research outputs found
The Impact of Physical Classroom Environment on Student Satisfaction and Student Evaluation of Teaching in the University Environment
Recently, many colleges and universities have made significant investments in upgraded classrooms and learning centers, incorporating such factors as tiered seating, customized lighting packages, upgraded desk and seat quality, and individual computers. To date, few studies have examined the impact of classroom environment at post-secondary institutions. The purpose of this study is to analyze the impact of classroom environment factors on individual student satisfaction measures and on student evaluation of teaching in the university environment. Two-hundred thirty-seven undergraduate business students were surveyed regarding their perceptions of classroom environment factors and their satisfaction with their classroom, instructor, and course. The results of the study indicate that students do perceive significant differences between standard and upgraded classrooms. Additionally, students express a preference for several aspects of upgraded classrooms, including tiered seating, lighting, and classroom noise control. Finally, students rate course enjoyment, classroom learning, and instructor organization higher in upgraded classrooms than in standard classrooms. The results of this study should benefit administrators who make capital and infrastructure decisions regarding college and university classroom improvements, faculty members who develop and rely upon student evaluations of teaching, and researchers who examine the factors impacting student satisfaction and learning
Lambda-Cold Dark Matter, Stellar Feedback, and the Galactic Halo Abundance Pattern
(Abridged) The hierarchical formation scenario for the stellar halo requires
the accretion and disruption of dwarf galaxies, yet low-metallicity halo stars
are enriched in alpha-elements compared to similar, low-metallicity stars in
dwarf spheroidal (dSph) galaxies. We address this primary challenge for the
hierarchical formation scenario for the stellar halo by combining chemical
evolution modelling with cosmologically-motivated mass accretion histories for
the Milky Way dark halo and its satellites. We demonstrate that stellar halo
and dwarf galaxy abundance patterns can be explained naturally within the LCDM
framework. Our solution relies fundamentally on the LCDM model prediction that
the majority of the stars in the stellar halo were formed within a few
relatively massive, ~5 x 10^10 Msun, dwarf irregular (dIrr)-size dark matter
halos, which were accreted and destroyed ~10 Gyr in the past. These systems
necessarily have short-lived, rapid star formation histories, are enriched
primarily by Type II supernovae, and host stars with enhanced [a/Fe]
abundances. In contrast, dwarf spheroidal galaxies exist within low-mass dark
matter hosts of ~10^9 Msun, where supernovae winds are important in setting the
intermediate [a/Fe] ratios observed. Our model includes enrichment from Type Ia
and Type II supernovae as well as stellar winds, and includes a
physically-motivated supernovae feedback prescription calibrated to reproduce
the local dwarf galaxy stellar mass - metallicity relation. We use
representative examples of the type of dark matter halos we expect to host a
destroyed ``stellar halo progenitor'' dwarf, a surviving dIrr, and a surviving
dSph galaxy, and show that their derived abundance patterns, stellar masses,
and gas masses are consistent with those observed for each type of system.Comment: 10 pages, 3 figures, version accepted by Ap
Quasiparticle transport in the vortex state of YBa_2Cu_3O_6.9
The effect of vortices on quasiparticle transport in cuprate superconductors
was investigated by measuring the low temperature thermal conductivity of
YBa_2Cu_3O_6.9 in magnetic fields up to 8 T. The residual linear term (as T \to
0) is found to increase with field, directly reflecting the occupation of
extended quasiparticle states. A study for different Zn impurity concentrations
reveals a good agreement with recent calculations for a d-wave superconductor,
thereby shedding light on the nature of scattering by both impurities and
vortices. It also provides a quantitative measure of the gap near the nodes.Comment: 4 pages, 2 included eps figures, significant new analysis wrt other
experiments, to appear in Phys Rev Lett 29 March 199
Safety and immunogenicity of boosting BCG vaccinated subjects with BCG: comparison with boosting with a new TB vaccine, MVA85A.
OBJECTIVES: To investigate the safety and immunogenicity of a booster BCG vaccination delivered intradermally in healthy, BCG vaccinated subjects and to compare with a previous clinical trial where BCG vaccinated subjects were boosted with a new TB vaccine, MVA85A. DESIGN: Phase I open label observational trial, in the UK. Healthy, HIV-negative, BCG vaccinated adults were recruited and vaccinated with BCG. The primary outcome was safety; the secondary outcome was cellular immune responses to antigen 85, overlapping peptides of antigen 85A and tuberculin purified protein derivative (PPD) detected by ex vivo interferon-gamma (IFN-gamma) ELISpot assay and flow cytometry. RESULTS AND CONCLUSIONS: BCG revaccination (BCG-BCG) was well tolerated, and boosting of pre-existing PPD-specific T cell responses was observed. However, when these results were compared with data from a previous clinical trial, where BCG was boosted with MVA85A (BCG-MVA85A), MVA85A induced significantly higher levels (>2-fold) of antigen 85-specific CD4+ T cells (both antigen and peptide pool responses) than boosting with BCG, up to 52 weeks post-vaccination (p = 0.009). To identify antigen 85A-specific CD8+ T cells that were not detectable by ex vivo ELISpot and flow cytometry, dendritic cells (DC) were used to amplify CD8+ T cells from PBMC samples. We observed low, but detectable levels of antigen 85A-specific CD8+ T cells producing IFNgamma (1.5% of total CD8 population) in the BCG primed subjects after BCG boosting in 1 (20%) of 5 subjects. In contrast, in BCG-MVA85A vaccinated subjects, high levels of antigen 85A-specific CD8+ T cells (up to 14% total CD8 population) were observed after boosting with MVA85A, in 4 (50%) of 8 subjects evaluated. In conclusion, revaccination with BCG resulted in modest boosting of pre-existing immune responses to PPD and antigen 85, but vaccination with BCG-MVA85A induced a significantly higher response to antigen 85 and generated a higher frequency of antigen 85A-specific CD8+ T cells. TRIAL REGISTRATION: ClinicalTrials.gov NCT00654316 NCT00427830
Using kinematic analyses to explore sensorimotor control impairments in children with 22q11.2 deletion syndrome
Background: The 22q11.2 deletion is associated with psychiatric and behavioural disorders, intellectual disability and multiple physical abnormalities. Recent research also indicates impaired coordination skills may be part of the clinical phenotype. This study aimed to characterise sensorimotor control abilities in children with 22q11.2 deletion syndrome (22q11.2DS) and investigate their relationships with co-occurring IQ impairments and psychopathology. Methods: Fifty-four children with 22q11.2DS and 24 unaffected sibling controls, comparable in age and gender, underwent kinematic analysis of their hand movements, whilst performing a battery of three visuo-manual coordination tasks that measured their tracking, aiming and steering abilities. Additionally, standardised assessments of full-scale IQ (FSIQ), attention deficit hyperactivity disorder, indicative autism spectrum disorder (ASD) and anxiety disorder symptomatology were conducted. Results: Children with 22q11.2DS showed deficits on seven of eight kinematic descriptors of movement quality across the three coordination tasks, compared to controls. Within 22q11.2DS cases, the extent of impairment on only three kinematic descriptors was significantly related to FSIQ after correction for multiple testing. Moreover, only error whilst visuo-manually tracking was nominally associated with ADHD symptom counts. Conclusions: Impairments in sensorimotor control are seen on a range of visuo-manual tasks in children with 22q11.2DS but the extent of these impairments are largely unrelated to the severity of other psychopathological and intellectual impairments commonly found in children with 22q11.2DS.</p
Boosting BCG with recombinant modified vaccinia ankara expressing antigen 85A: Different boosting intervals and implications for efficacy trials
Objectives. To investigate the safety and immunogenicity of boosting BCG with modified vaccinia Ankara expressing antigen
85A (MVA85A), shortly after BCG vaccination, and to compare this first with the immunogenicity of BCG vaccination alone and
second with a previous clinical trial where MVA85A was administered more than 10 years after BCG vaccination. Design. There
are two clinical trials reported here: a Phase I observational trial with MVA85A; and a Phase IV observational trial with BCG.
These clinical trials were all conducted in the UK in healthy, HIV negative, BCG naı¨ve adults. Subjects were vaccinated with BCG
alone; or BCG and then subsequently boosted with MVA85A four weeks later (short interval). The outcome measures, safety
and immunogenicity, were monitored for six months. The immunogenicity results from this short interval BCG prime–MVA85A
boost trial were compared first with the BCG alone trial and second with a previous clinical trial where MVA85A vaccination
was administered many years after vaccination with BCG. Results. MVA85A was safe and highly immunogenic when
administered to subjects who had recently received BCG vaccination. When the short interval trial data presented here were
compared with the previous long interval trial data, there were no significant differences in the magnitude of immune
responses generated when MVA85A was administered shortly after, or many years after BCG vaccination. Conclusions. The
clinical trial data presented here provides further evidence of the ability of MVA85A to boost BCG primed immune responses.
This boosting potential is not influenced by the time interval between prior BCG vaccination and boosting with MVA85A. These
findings have important implications for the design of efficacy trials with MVA85A. Boosting BCG induced anti-mycobacterial
immunity in either infancy or adolescence are both potential applications for this vaccine, given the immunological data
presented here. Trial Registration. ClinicalTrials.Oxford University was the sponsor for all the clinical trials reported here
Development and Application of an Interdisciplinary Rapid Message Testing Model for COVID-19 in North Carolina
Introduction
From the onset of the COVID-19 pandemic, public health officials have sought to develop evidence-based messages to reduce COVID-19 transmission by communicating key information to media outlets and the public. We describe the development of an interdisciplinary rapid message testing model to quickly create, test, and share messages with public health officials for use in health campaigns and policy briefings.
Methods
An interdisciplinary research team from the University of North Carolina at Chapel Hill assembled in March 2020 to assist the state health department in developing evidence-based messages to influence social distancing behaviors in the state. We developed and iteratively executed a rapid message testing model; the components of the 4-step model were message creation, survey development, survey administration, and analysis and presentation to health department officials. The model was executed 4 times, each during a 7-day period in April and May, and each subsequent survey included new phrasing and/or messaging informed by the previous week’s survey. A total of 917 adults from North Carolina participated in the 4 surveys.
Results
Survey participants rated messages focused on protecting oneself and others higher than messages focused on norms and fear-based approaches. Pairing behaviors with motivations increased participants’ desire to social distance across all themes and subgroups. For example, adding “Protect your grandmother, your neighbor with cancer, and your best friend with asthma,” to messaging received a 0.9-point higher score than the base message, “Stay 6 feet apart from others when out in public.”
Practice Implications
Our model to promote social distancing in North Carolina during the COVID-19 pandemic can be used for rapid, iterative message testing during public health emergencies
The role of the RACK1 ortholog Cpc2p in modulating pheromone-induced cell cycle arrest in fission yeast
The detection and amplification of extracellular signals requires the involvement of multiple protein components. In mammalian cells the receptor of activated C kinase (RACK1) is an important scaffolding protein for signal transduction networks. Further, it also performs a critical function in regulating the cell cycle by modulating the G1/S transition. Many eukaryotic cells express RACK1 orthologs, with one example being Cpc2p in the fission yeast Schizosaccharomyces pombe. In contrast to RACK1, Cpc2p has been described to positively regulate, at the ribosomal level, cells entry into M phase. In addition, Cpc2p controls the stress response pathways through an interaction with Msa2p, and sexual development by modulating Ran1p/Pat1p. Here we describe investigations into the role, which Cpc2p performs in controlling the G protein-mediated mating response pathway. Despite structural similarity to Gβ-like subunits, Cpc2p appears not to function at the G protein level. However, upon pheromone stimulation, cells overexpressing Cpc2p display substantial cell morphology defects, disorientation of septum formation and a significantly protracted G1 arrest. Cpc2p has the potential to function at multiple positions within the pheromone response pathway. We provide a mechanistic interpretation of this novel data by linking Cpc2p function, during the mating response, with its previous described interactions with Ran1p/Pat1p. We suggest that overexpressing Cpc2p prolongs the stimulated state of pheromone-induced cells by increasing ste11 gene expression. These data indicate that Cpc2p regulates the pheromone-induced cell cycle arrest in fission yeast by delaying cells entry into S phase
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