1,161 research outputs found
Co-Teaching During Teacher Training Periods : Experiences of Finnish Special Education and General Education Teacher Candidates
publishedVersio
Adolescentsâ attitudes, preferences and perceived behaviours regarding healthy eating and whole grains from a gender and health interest perspective
Background: A healthy diet is important not only for the growth and development of the human body but also for the prevention of chronic diseases. However, most Swedish adolescents do not follow dietary recommen-dations, especially the intake of whole grain is very low. To create targeted conditions for healthy food choices amongst adolescents, comprehensive knowledge of factors related to adolescentsâ unhealthy and healthy eating is needed. Objective: To investigate adolescentsâ attitudes, preferences and perceived behaviours regarding healthy eating, with a specific focus on whole grains and to evaluate differences between genders and between adolescents with higher versus lower health interest. Design: A total of 1,178 Swedish adolescents responded to a questionnaire about their attitudes, preferences and perceived behabviours towards healthy eating and whole grains, and their general interest in nutrition and health. Results of girls and boys were compared, as well as adolescents with a higher versus lower health interest. Results: Displays information about healthy eating among adolescents and a comprehensive set of factors that may affect their ability to eat healthier. Overall, adolescents had a positive attitude towards food and health, but less than half felt that they managed to eat healthy. The consumption of different whole grain products was low, although the willingness to eat healthier and more whole grain was high. The most reported barrier to healthy eating, as well as increasing whole grain intake, was the unavailability of tasty healthy products, taste being even more important for adolescents with a low health interest than those with a high interest. Whole grain consumption and factors increasing the willingness of whole grain consumption were most prominent not only in adolescents with high health interest but also in girls compared with boys. Conclusion: The results show good potential to improve dietary habits amongst adolescents. Taste and avail-ability of healthy products were rated the most important, whilst knowledge about the productsâ healthiness was rated the least important, especially amongst those with low health interest. By focusing on the attitudes and preferences of adolescents, the effectiveness may increase of initiatives to improve their dietary habits
Dual EGFR inhibition in combination with anti-VEGF treatment: a phase I clinical trial in non-small cell lung cancer.
BackgroundPreclinical data indicate EGFR signals through both kinase-dependent and independent pathways and that combining a small-molecule EGFR inhibitor, EGFR antibody, and/or anti-angiogenic agent is synergistic in animal models.MethodsWe conducted a dose-escalation, phase I study combining erlotinib, cetuximab, and bevacizumab. The subset of patients with non-small cell lung cancer (NSCLC) was analyzed for safety and response.ResultsThirty-four patients with NSCLC (median four prior therapies) received treatment on a range of dose levels. The most common treatment-related grade â„2 adverse events were rash (n=14, 41%), hypomagnesemia (n=9, 27%), and fatigue (n=5, 15%). Seven patients (21%) achieved stable disease (SD) â„6 months, two achieved a partial response (PR) (6%), and two achieved an unconfirmed partial response (uPR) (6%) (total=32%). We observed SDâ„6 months/PR/uPR in patients who had received prior erlotinib and/or bevacizumab, those with brain metastases, smokers, and patients treated at lower dose levels. Five of 16 patients (31%) with wild-type EGFR experienced SDâ„6 months or uPR. Correlation between grade of rash and rate of SDâ„6 months/PR was observed (p less than 0.01).ConclusionThe combination of erlotinib, cetuximab, and bevacizumab was well-tolerated and demonstrated antitumor activity in heavily pretreated patients with NSCLC
How surface properties influence mineral dust emissions in the Sahelian region ? A modelling case study during AMMA
Tropical mesoscale convective systems (MCSs) are a prominent feature of the African meteorology. A continuous monitoring of the aeolian activity in an experimental site located in Niger shows that such events are responsible for the major part of the annual local wind erosion, i.e. for most of the Sahelian dust emissions [Rajot, 2001]. However, the net effect of these MCSs on mineral dust budget has to be estimated: on the one hand, these systems produce extremely high surface wind velocities leading to intense dust uptake, but on the other hand, rainfalls associated with these systems can efficiently remove the emitted dust from the atmosphere. High resolution modelling appears as a relevant approach to correctly reproduce the surface meteorology associated with such meteorological systems [Bouet et al., submitted]. The question now arising concerns the reliability of surface characteristics available for the Sahelian region, especially soil texture and surface roughness, which are critical parameters for dust emissions. Contrary to arid regions, which are now well documented, data is still missing to correctly characterize semi-arid regions like the Sahel. This is in particular due to the well pronounced annual cycles of precipitations and vegetation in these regions and to the impact of land-use on surface properties. This study focuses on a case study of dust emission associated with the passage of a MCS observed during one of the Special Observing Periods of the international African Monsoon Multidisciplinary Analysis (AMMA – SOPs 1-2) program. The simulations were made using the Regional Atmospheric Modeling System (RAMS, Cotton et al. [2003]) coupled online with the dust production model developed by Marticorena and Bergametti [1995] and recently improved by Laurent et al. [2008] for Africa. The sensitivity of dust emission associated with the passage of the MCS to surface features is investigated using different data sets of surface properties (Harmonized World Soil Database, HWSD) and land-use (GLOBCOVER). In-situ measurements of dust concentrations (both ground-based and airborne), and of dust emission flux are used to validate the simulations
Complex regeneration responses of eight tree species to partial harvest in mixedwood forests of northeastern North America
Ecosystem-based forest management associated with partial harvesting (PH) is intended to balance ecological
and economic values of sustainable forest management. The potential for delayed growth response and elevated
mortality of advance regeneration following PH remains a critical concern, and may present a barrier to more
widespread implementation of this approach. We used 835 permanent continuous forest inventory plots to
examine the rate and time course of species-specific regeneration growth and mortality of eight tree species in
the first fifteen years following operational partial harvests in the mixed-species forests of Maine, United States.
We aimed to provide a quantitative understanding on how regeneration of different species responded to PH in
terms of growth and mortality. In addition, we evaluated how the patterns and magnitudes of growth and
mortality responses developed over time, if these responses occur gradually or suddenly, and if the patterns of the
responses were persistent. We found that the response magnitude, temporal trajectories of responses, and the
length of initial lag-period largely varied across species, PH treatments, and the variables examined. For sapling
diameter growth, paper birch (Betula papyrifera Marshall) and red maple (Acer rubrum L.) showed immediate
responses to high-intensity PH, while a five-year lag-period was observed in balsam fir (Abies balsamea (L.) Mill.),
American beech (Fagus grandifolia Ehrh.), red spruce (Picea rubens Sarg.) and eastern hemlock (Tsuga canadensis
(L.) Carri`ere) and a 10-year lag period in northern white-cedar (Thuja occidentalis L.). The initial increase in
sapling mortality was observed in balsam fir, American beech, red maple and northern white-cedar, but not in
other species. Sapling survival reached a stable state irrespective of species after the initial five-years following
harvests. In partially harvested stands, identifying preharvest conditions related to postharvest density, growth,
and mortality was complex and interacted with time since harvest. Our results suggest that broad application of
PH only results in species-specific gains, losses, and delays in regeneration responses within mixed-species
stands. Future research should consider PH in combination with other treatments to initiate immediate responses
to a wider range of species.We thank to US Forest Service Forest Inventory and Analysis (FIA)
for access to the long-term database. Funding was provided by the
United States National ScienceFoundationâs Center for Advanced
Forestry Systems (#1915078) and R-II Track-2 FEC (#1920908) and
from NSRC Alliance (ALLRP 557166 - 20)
Automated analysis of short responses in an interactive synthetic tutoring system for introductory physics
Citation: Nakamura, C. M., Murphy, S. K., Christel, M. G., Stevens, S. M., & Zollman, D. A. (2016). Automated analysis of short responses in an interactive synthetic tutoring system for introductory physics. Physical Review Physics Education Research, 12(1), 16. doi:10.1103/PhysRevPhysEducRes.12.010122Computer-automated assessment of students' text responses to short-answer questions represents an important enabling technology for online learning environments. We have investigated the use of machine learning to train computer models capable of automatically classifying short-answer responses and assessed the results. Our investigations are part of a project to develop and test an interactive learning environment designed to help students learn introductory physics concepts. The system is designed around an interactive video tutoring interface. We have analyzed 9 with about 150 responses or less. We observe for 4 of the 9 automated assessment with interrater agreement of 70% or better with the human rater. This level of agreement may represent a baseline for practical utility in instruction and indicates that the method warrants further investigation for use in this type of application. Our results also suggest strategies that may be useful for writing activities and questions that are more appropriate for automated assessment. These strategies include building activities that have relatively few conceptually distinct ways of perceiving the physical behavior of relatively few physical objects. Further success in this direction may allow us to promote interactivity and better provide feedback in online learning systems. These capabilities could enable our system to function more like a real tutor
A Few Considerations on Structural and Logical Composition in Specification Theories
Over the last 20 years a large number of automata-based specification
theories have been proposed for modeling of discrete,real-time and
probabilistic systems. We have observed a lot of shared algebraic structure
between these formalisms. In this short abstract, we collect results of our
work in progress on describing and systematizing the algebraic assumptions in
specification theories.Comment: In Proceedings FIT 2010, arXiv:1101.426
Comparison of commonly used methods in random effects meta-analysis:Application to preclinical data in drug discovery research
Background Meta-analysis of preclinical data is used to evaluate the consistency of findings and to inform the design and conduct of future studies. Unlike clinical meta-analysis, preclinical data often involve many heterogeneous studies reporting outcomes from a small number of animals. Here, we review the methodological challenges in preclinical meta-analysis in estimating and explaining heterogeneity in treatment effects.Methods Assuming aggregate-level data, we focus on two topics: (1) estimation of heterogeneity using commonly used methods in preclinical meta-analysis: method of moments (DerSimonian and Laird; DL), maximum likelihood (restricted maximum likelihood; REML) and Bayesian approach; (2) comparison of univariate versus multivariable meta-regression for adjusting estimated treatment effects for heterogeneity. Using data from a systematic review on the efficacy of interleukin-1 receptor antagonist in animals with stroke, we compare these methods, and explore the impact of multiple covariates on the treatment effects.Results We observed that the three methods for estimating heterogeneity yielded similar estimates for the overall effect, but different estimates for between-study variability. The proportion of heterogeneity explained by a covariate is estimated larger using REML and the Bayesian method as compared with DL. Multivariable meta-regression explains more heterogeneity than univariate meta-regression.Conclusions Our findings highlight the importance of careful selection of the estimation method and the use of multivariable meta-regression to explain heterogeneity. There was no difference between REML and the Bayesian method and both methods are recommended over DL. Multiple meta-regression is worthwhile to explain heterogeneity by more than one variable, reducing more variability than any univariate models and increasing the explained proportion of heterogeneity
The ecology of methane in streams and rivers: patterns, controls, and global significance
Streams and rivers can substantially modify organic carbon (OC) inputs from terrestrial landscapes, and much of this processing is the result of microbial respiration. While carbon dioxide (COâ) is the major endâproduct of ecosystem respiration, methane (CHâ) is also present in many fluvial environments even though methanogenesis typically requires anoxic conditions that may be scarce in these systems. Given recent recognition of the pervasiveness of this greenhouse gas in streams and rivers, we synthesized existing research and data to identify patterns and drivers of CHâ, knowledge gaps, and research opportunities. This included examining the history of lotic CH4 research, creating a database of concentrations and fluxes (MethDB) to generate a globalâscale estimate of fluvial CHâ efflux, and developing a conceptual framework and using this framework to consider how human activities may modify fluvial CHâ dynamics. Current understanding of CHâ in streams and rivers has been strongly influenced by goals of understanding OC processing and quantifying the contribution of CHâ to ecosystem C fluxes. Less effort has been directed towards investigating processes that dictate in situ CHâ production and loss. CHâ makes a meager contribution to watershed or landscape C budgets, but streams and rivers are often significant CHâ sources to the atmosphere across these same spatial extents. Most fluvial systems are supersaturated with CHâ and we estimate an annual global emission of 26.8 Tg CHâ, equivalent to ~15â40% of wetland and lake effluxes, respectively. Less clear is the role of CHâ oxidation, methanogenesis, and total anaerobic respiration to whole ecosystem production and respiration. Controls on CHâ generation and persistence can be viewed in terms of proximate controls that influence methanogenesis (organic matter, temperature, alternative electron acceptors, nutrients) and distal geomorphic and hydrologic drivers. Multiple controls combined with its extreme redox status and low solubility result in high spatial and temporal variance of CHâ in fluvial environments, which presents a substantial challenge for understanding its largerâscale dynamics. Further understanding of CHâ production and consumption, anaerobic metabolism, and ecosystem energetics in streams and rivers can be achieved through more directed studies and comparison with knowledge from terrestrial, wetland, and aquatic disciplines."Support for this paper was provided by funding from the North Temperate Lakes LTER program, NSF DEBâ0822700."https://esajournals.onlinelibrary.wiley.com/doi/full/10.1890/15-102
Pig slurry characteristics, nutrient balance and biogas production as affected by separation and acidification
- âŠ