1,019 research outputs found
Minority Language Learners: A look at culturally relevant resources available at elementary schools in North Carolina
English language learners represent a growing population that requires educators to take a serious look at instructional programs to support these students' learning. The issue of educating these students has received increased emphasis due to the requirements of the No Child Left Behind Act and schools' accountability for achievement of various student populations. English language learner students are at an obvious academic disadvantage since content area curriculum is typically taught in English. This study will focus on theories of language acquisition, strategies to support the needs of English language learner teacher and learners, and specifically look at the library's role in providing resources
A novel spin wave expansion, finite temperature corrections and order from disorder effects in the double exchange model
The magnetic excitations of the double exchange (DE) model are usually
discussed in terms of an equivalent ferromagnetic Heisenberg model. We argue
that this equivalence is valid only at a quasi--classical level -- both quantum
and thermal corrections to the magnetic properties of DE model differ from any
effective Heisenberg model because its spin excitations interact only
indirectly, through the exchange of charge fluctuations. To demonstrate this,
we perform a novel large S expansion for the coupled spin and charge degrees of
freedom of the DE model, aimed at projecting out all electrons not locally
aligned with core spins. We generalized the Holstein--Primakoff transformation
to the case when the length of the spin is by itself an operator, and
explicitly constructed new fermionic and bosonic operators to fourth order in
1/\sqrt{S}. This procedure removes all spin variables from the Hund coupling
term, and yields an effective Hamiltonian with an overall scale of electron
hopping, for which we evaluate corrections to the magnetic and electronic
properties in 1/S expansion to order O(1/S^2). We also consider the effect of a
direct superexchange antiferromagnetic interaction between core spins. We find
that the competition between ferromagnetic double exchange and an
antiferromagnetic superexchange provides a new example of an "order from
disorder" phenomenon -- when the two interactions are of comparable strength,
an intermediate spin configuration (either a canted or a spiral state) is
selected by quantum and/or thermal fluctuations.Comment: 21 pages revtex, 11 eps figure
A Roadmap to Advance Marine and Coastal Monitoring, Biodiversity Assessment, and International Reporting: A Developing Nation Perspective
Despite the increasing number of tools and indicators to measure biodiversity status and
trends, many developing countries struggle to initiate and advance coastal and marine
assessments needed to monitor and track national and international progress in
biodiversity targets. We identified five key challenges that hinder progress in this
context, based on a national marine assessment workshop held in South Africa, and
developed recommendations and tangible actions to address these challenges drawing
from multiple national assessments, regional initiatives, and global collaborations over the
last 15 years. Challenges include a poor understanding of methods, limited capacity and
funding for assessments, a lack of systematic approaches to biodiversity assessment and
indicator development, and scattered efforts that often fail to link science to policy. Key
actions could enable the development of a coordinated framework to feed into policy and
decision-making at multiple scales. We provide South African examples to highlight a
developing country’s progress toward marine biodiversity assessment and provide a
roadmap to integrated monitoring, assessment, and reporting based on positive
outcomes. Recommendations to address challenges include building collective
understanding of assessment tools and methods, prioritizing pressures urgently
needing mitigation measures, using relevant indicators to support reporting at multiple
scales, applying coordinated approaches to identify gaps and opportunities,
codeveloping coordinated approaches with direct policy links, and leveraging resources
and technical capacity for iterative improvement. This roadmap can guide developing and
developed countries and support global best practices to collaboratively advance marine
and coastal ecosystem monitoring and assessment at multiple scales for meeting
many objective
Studies of group velocity reduction and pulse regeneration with and without the adiabatic approximation
We present a detailed semiclassical study on the propagation of a pair of
optical fields in resonant media with and without adiabatic approximation. In
the case of near and on resonance excitation, we show detailed calculation,
both analytically and numerically, on the extremely slowly propagating probe
pulse and the subsequent regeneration of a pulse via a coupling laser. Further
discussions on the adiabatic approximation provide many subtle understandings
of the process including the effect on the band width of the regenerated
optical field. Indeed, all features of the optical pulse regeneration and most
of the intricate details of the process can be obtained with the present
treatment without invoke a full field theoretical method. For very far off
resonance excitation, we show that the analytical solution is nearly detuning
independent, a surprising result that is vigorously tested and compared to
numerical calculations with very good agreement.Comment: 13 pages, 15 figures, submitted to Phys. Rev.
Driver glance behaviors and scanning patterns: Applying static and dynamic glance measures to the analysis of curve driving with secondary tasks
Performing secondary tasks (or non‐driving‐related tasks) while driving on curved roads may be risky and unsafe. The purpose of this study was to explore whether driving safety in situations involving curved roads and secondary tasks can be evaluated using multiple measures of eye movement. We adopted Markov‐based transition algorithms (i.e., transition/stationary probabilities, entropy) to quantify drivers’ dynamic eye movement patterns, in addition to typical static visual measures, such as frequency and duration of glances. The algorithms were evaluated with data from an experiment (Jeong & Liu, 2019) involving multiple road curvatures and stimulus‐response secondary task types. Drivers were more likely to scan only a few areas of interest with a long duration in sharper curves. Total head‐down glance time was longer in less sharp curves in the experiment, but the probability of head‐down glances was higher in sharper curves over the long run. The number of reliable transitions between areas of interest varied with the secondary task type. The visual scanning patterns for visually undemanding tasks were as random as those for visually demanding tasks. Markov‐based measures of dynamic eye movements provided insights to better understand drivers’ underlying mental processes and scanning strategies, compared with typical static measures. The presented methods and results can be useful for in‐vehicle systems design and for further analysis of visual scanning patterns in the transportation domain.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151975/1/hfm20798_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151975/2/hfm20798.pd
A Randomized Trial to Compare a Tailored Web-Based Intervention and Tailored Phone Counseling to Usual Care for Increasing Colorectal Cancer Screening
Background: Colorectal cancer mortality could be decreased with risk-appropriate cancer screening. We examined the efficacy of three tailored interventions compared with usual care for increasing screening adherence.
Methods: Women (n = 1,196) ages 51 to 74, from primary care networks and nonadherent to colorectal cancer guidelines, were randomized to (1) usual care, (2) tailored Web intervention, (3) tailored phone intervention, or (4) tailored Web + phone intervention. Average-risk women could select either stool test or colonoscopy, whereas women considered at higher than average risk received an intervention that supported colonoscopy. Outcome data were collected at 6 months by self-report, followed by medical record confirmation (attrition of 23%). Stage of change for colorectal cancer screening (precontemplation or contemplation) was assessed at baseline and 6 months.
Results: The phone (41.7%, P < 0.0001) and combined Web + phone (35.8%, P < 0.001) interventions significantly increased colorectal cancer screening by stool test compared with usual care (11.1%), with ORs ranging from 5.4 to 6.8 in models adjusted for covariates. Colonoscopy completion did not differ between groups except that phone significantly increased colonoscopy completion compared with usual care for participants in the highest tertile of self-reported fear of cancer.
Conclusions: A tailored phone with or without a Web component significantly increased colorectal cancer screening compared with usual care, primarily through stool testing, and phone significantly increased colonoscopy compared with usual care but only among those with the highest levels of baseline fear.
Impact: This study supports tailored phone counseling with or without a Web program for increasing colorectal cancer screening in average-risk women
An approach for the identification of targets specific to bone metastasis using cancer genes interactome and gene ontology analysis
Metastasis is one of the most enigmatic aspects of cancer pathogenesis and is
a major cause of cancer-associated mortality. Secondary bone cancer (SBC) is a
complex disease caused by metastasis of tumor cells from their primary site and
is characterized by intricate interplay of molecular interactions.
Identification of targets for multifactorial diseases such as SBC, the most
frequent complication of breast and prostate cancers, is a challenge. Towards
achieving our aim of identification of targets specific to SBC, we constructed
a 'Cancer Genes Network', a representative protein interactome of cancer genes.
Using graph theoretical methods, we obtained a set of key genes that are
relevant for generic mechanisms of cancers and have a role in biological
essentiality. We also compiled a curated dataset of 391 SBC genes from
published literature which serves as a basis of ontological correlates of
secondary bone cancer. Building on these results, we implement a strategy based
on generic cancer genes, SBC genes and gene ontology enrichment method, to
obtain a set of targets that are specific to bone metastasis. Through this
study, we present an approach for probing one of the major complications in
cancers, namely, metastasis. The results on genes that play generic roles in
cancer phenotype, obtained by network analysis of 'Cancer Genes Network', have
broader implications in understanding the role of molecular regulators in
mechanisms of cancers. Specifically, our study provides a set of potential
targets that are of ontological and regulatory relevance to secondary bone
cancer.Comment: 54 pages (19 pages main text; 11 Figures; 26 pages of supplementary
information). Revised after critical reviews. Accepted for Publication in
PLoS ON
Association of Accelerometry-Measured Physical Activity and Cardiovascular Events in Mobility-Limited Older Adults: The LIFE (Lifestyle Interventions and Independence for Elders) Study.
BACKGROUND:Data are sparse regarding the value of physical activity (PA) surveillance among older adults-particularly among those with mobility limitations. The objective of this study was to examine longitudinal associations between objectively measured daily PA and the incidence of cardiovascular events among older adults in the LIFE (Lifestyle Interventions and Independence for Elders) study. METHODS AND RESULTS:Cardiovascular events were adjudicated based on medical records review, and cardiovascular risk factors were controlled for in the analysis. Home-based activity data were collected by hip-worn accelerometers at baseline and at 6, 12, and 24 months postrandomization to either a physical activity or health education intervention. LIFE study participants (n=1590; age 78.9±5.2 [SD] years; 67.2% women) at baseline had an 11% lower incidence of experiencing a subsequent cardiovascular event per 500 steps taken per day based on activity data (hazard ratio, 0.89; 95% confidence interval, 0.84-0.96; P=0.001). At baseline, every 30 minutes spent performing activities ≥500 counts per minute (hazard ratio, 0.75; confidence interval, 0.65-0.89 [P=0.001]) were also associated with a lower incidence of cardiovascular events. Throughout follow-up (6, 12, and 24 months), both the number of steps per day (per 500 steps; hazard ratio, 0.90, confidence interval, 0.85-0.96 [P=0.001]) and duration of activity ≥500 counts per minute (per 30 minutes; hazard ratio, 0.76; confidence interval, 0.63-0.90 [P=0.002]) were significantly associated with lower cardiovascular event rates. CONCLUSIONS:Objective measurements of physical activity via accelerometry were associated with cardiovascular events among older adults with limited mobility (summary score >10 on the Short Physical Performance Battery) both using baseline and longitudinal data. CLINICAL TRIAL REGISTRATION:URL: http://www.clinicaltrials.gov. Unique identifier: NCT01072500
Magnetoelectric ordering of BiFeO3 from the perspective of crystal chemistry
In this paper we examine the role of crystal chemistry factors in creating
conditions for formation of magnetoelectric ordering in BiFeO3. It is generally
accepted that the main reason of the ferroelectric distortion in BiFeO3 is
concerned with a stereochemical activity of the Bi lone pair. However, the lone
pair is stereochemically active in the paraelectric orthorhombic beta-phase as
well. We demonstrate that a crucial role in emerging of phase transitions of
the metal-insulator, paraelectric-ferroelectric and magnetic disorder-order
types belongs to the change of the degree of the lone pair stereochemical
activity - its consecutive increase with the temperature decrease. Using the
structural data, we calculated the sign and strength of magnetic couplings in
BiFeO3 in the range from 945 C down to 25 C and found the couplings, which
undergo the antiferromagnetic-ferromagnetic transition with the temperature
decrease and give rise to the antiferromagnetic ordering and its delay in
regard to temperature, as compared to the ferroelectric ordering. We discuss
the reasons of emerging of the spatially modulated spin structure and its
suppression by doping with La3+.Comment: 18 pages, 5 figures, 3 table
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PINOT: an intuitive resource for integrating protein-protein interactions
The past decade has seen the rise of omics data, for the understanding of biological systems in health and disease. This wealth of data includes protein-protein interaction (PPI) derived from both low and high-throughput assays, which is curated into multiple databases that capture the extent of available information from the peer-reviewed literature. Although these curation efforts are extremely useful, reliably downloading and integrating PPI data from the variety of available repositories is challenging and time consuming.
We here present a novel user-friendly web-resource called PINOT (Protein Interaction Network Online Tool; available at http://www.reading.ac.uk/bioinf/PINOT/PINOT_form.html) to optimise the collection and processing of PPI data from the IMEx consortium associated repositories (members and observers) and from WormBase for constructing, respectively, human and C. elegans PPI networks.
Users submit a query containing a list of proteins of interest for which PINOT will mine PPIs. PPI data is downloaded, merged, quality checked, and confidence scored based on the number of distinct methods and publications in which each interaction has been reported. Examples of PINOT applications are provided to highlight the performance, the ease of use and the potential applications of this tool.
PINOT is a tool that allows users to survey the literature, extracting PPI data for a list of proteins of interest. The comparison with analogous tools showed that PINOT was able to extract similar numbers of PPIs while incorporating a set of innovative features. PINOT processes both small and large queries, it downloads PPIs live through PSICQUIC and it applies quality control filters on the downloaded PPI annotations (i.e. removing the need of manual inspection by the user). PINOT provides the user with information on detection methods and publication history for each of the downloaded interaction data entry and provides results in a table format that can be easily further customised and/or directly uploaded in a network visualization software
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