1,558 research outputs found
Developing a complex portrait of content teaching for multilingual learners via nonlinear theoretical understandings
Utilizing a complex theory of teacher learning and practice, this chapter analyzes ~120 empirical studies of content teacher development (both pre- and inservice) for working with multilingual learners as well as research on content teaching for multilingual students. Our analysis identified three dimensions of quality content teaching for multilingual learners that are complex and intricately connected: context, orientations and pedagogy. This chapter explores the results of our literature analysis and argues for improving content teaching for multilingual students through improved theoretically grounded research that embraces, explores and accounts for the expansive complexities inherent in teacher learning and practice
Pilot interaction with automated airborne decision making systems
Progress was made in the three following areas. In the rule-based modeling area, two papers related to identification and significane testing of rule-based models were presented. In the area of operator aiding, research focused on aiding operators in novel failure situations; a discrete control modeling approach to aiding PLANT operators was developed; and a set of guidelines were developed for implementing automation. In the area of flight simulator hardware and software, the hardware will be completed within two months and initial simulation software will then be integrated and tested
The SAMPLE Experiment and Weak Nucleon Structure
One of the key elements to understanding the structure of the nucleon is the
role of its quark-antiquark sea in its ground state properties such as charge,
mass, magnetism and spin. In the last decade, parity-violating electron
scattering has emerged as an important tool in this area, because of its
ability to isolate the contribution of strange quark-antiquark pairs to the
nucleon's charge and magnetism. The SAMPLE experiment at the MIT-Bates
Laboratory, which has been focused on s-sbar contributions to the proton's
magnetic moment, was the first of such experiments and its program has recently
been completed. In this paper we give an overview of some of the experimental
aspects of parity-violating electron scattering, briefly review the theoretical
predictions for strange quark form factors, summarize the SAMPLE measurements,
and place them in context with the program of experiments being carried out at
other electron scattering facilities such as Jefferson Laboratory and the Mainz
Microtron.Comment: 61 pages, review articl
Cultural Competency Observation Tool
This observational assessment rubric includes rating of the elements of patient centered communication defined in the Kalamazoo Consensus Statement regarding patient centered communication: These are augmented with sections that highlight factors that emerged in our observations specific to intercultural communication such as language and interpreters, nonverbal communication, mental and social issues with a large cultural overlay (mental health, pain, and disability). In addition, the tool incorporates issues specific to the medical context such as professional competence and professional regard. The rubric is also informed by the developmental model of intercultural sensitivity and Dreyfus\u27s phenomenology of skill acquisition with skill levels progressing through the stages: novice, beginner, competence, proficient, mastery
Non-thermal excitation and ionization in supernovae
We incorporate non-thermal excitation and ionization processes arising from
non-thermal electrons that result from \gamma-ray energy deposition, into our
radiative transfer code CMFGEN. The non-thermal electron distribution is
obtained by solving the Spencer-Fano equation using the procedure of Kozma &
Fransson (1992). We applied the non-thermal calculations to the blue supergiant
explosion model whose early evolution was studied in Dessart & Hillier (2010).
Non-thermal processes generally increase excitation and ionization and decrease
the temperature of the ejecta. We confirm that non-thermal processes are
crucial for modeling the nebular spectra. Both optical HI and HeI lines are
significantly strengthened. While optical HeI lines are not easily discerned in
observational spectra due to severe blending with other lines, HeI 2.058 \mu m
provides an excellent opportunity to infer the influence of non-thermal
processes. We also discuss the processes controlling the formation of the HeI
lines during the nebular epoch. Most lines of other species are only slightly
affected. We also show that the inclusion of FeI has substantial
line-blanketing effects on the optical spectra. Our model spectra and synthetic
light curves are compared to the observations of SN 1987A. The spectral
evolution shows broad agreement with the observations, especially H\alpha. The
uncertainties of the non-thermal solver are studied, and are expected to be
small. With this new addition of non-thermal effects in CMFGEN, we now treat
all known important processes controlling the radiative transfer of a supernova
ejecta, whatever the type and the epoch.Comment: 18 pages, 22 figures, accepted to MNRA
The Nature of Radio Emission from Distant Galaxies: The 1.4 GHz Observations
We have conducted a deep radio survey with the Very Large Array at 1.4 GHz of
a region containing the Hubble Deep Field. This survey overlaps previous
observations at 8.5 GHz allowing us to investigate the radio spectral
properties of microjansky sources to flux densities greater than 40 Jy at
1.4 GHz and greater than 8 Jy at 8.5 GHz. A total of 371 sources have been
catalogued at 1.4 GHz as part of a complete sample within 20\arcmin ~of the
HDF. The differential source count for this region is only marginally
sub-Euclidean and is given by
srJy. Above about 100 Jy the radio source count is
systematically lower in the HDF as compared to other fields. We conclude that
there is clustering in our radio sample on size scales of 1\arcmin - 40\arcmin
\.
The 1.4 GHz selected sample shows that the radio spectral indices are
preferentially steep () and the sources are
moderately extended with average angular size = 1.8\arcsec . Optical
identification with disk-type systems at 0.5-0.8 suggests that
synchrotron emission, produced by supernovae remnants, is powering the radio
emission in the majority of sources. The 8.5 GHz sample contains primarily
moderately flat spectrum sources (), with less than
15% inverted. We argue that we may be observing an increased fraction of
optically thin bremsstrahlung over synchrotron radiation in these distant
star-forming galaxies.Comment: 31 pages, 5 tables, 10 figures, to appear in Jan. 2000 Ap
Why do women seek ultrasound scans from commercial providers during pregnancy?
The commercial availability of ultrasound scans for pregnant women has been controversial yet little is known about why women make use of such services. This article reports on semi-structured interviews with women in the UK who have booked a commercial scan, focusing on the reasons women gave for booking commercially provided ultrasound during a low-risk pregnancy. Participantsâ reasons for booking a scan are presented in five categories: finding out the sex of the foetus; reassurance; seeing the baby; acquiring keepsakes and facilitating bonding. Our analysis demonstrates that women's reasons for booking commercial scans are often multiple and are shaped by experiences of antenatal care as well as powerful cultural discourses related to âgoodâ parenting and the use of technology in pregnancy. Sociological and public debate about the availability of commercial ultrasound and its social and personal impacts should consider the wider sociocultural context that structures women's choices to make use of such services
Development of a new pan-European testate amoeba transfer function for reconstructing peatland palaeohydrology
In the decade since the first pan-European testate amoeba-based transfer function for peatland palaeohydrological reconstruction was published, a vast amount of additional data collection has been undertaken by the research community. Here, we expand the pan-European dataset from 128 to 1799 samples, spanning 35° of latitude and 55° of longitude. After the development of a new taxonomic scheme to permit compilation of data from a wide range of contributors and the removal of samples with high pH values, we developed ecological transfer functions using a range of model types and a dataset of âŒ1300 samples. We rigorously tested the efficacy of these models using both statistical validation and independent test sets with associated instrumental data. Model performance measured by statistical indicators was comparable to other published models. Comparison to test sets showed that taxonomic resolution did not impair model performance and that the new pan-European model can therefore be used as an effective tool for palaeohydrological reconstruction. Our results question the efficacy of relying on statistical validation of transfer functions alone and support a multi-faceted approach to the assessment of new models. We substantiated recent advice that model outputs should be standardised and presented as residual values in order to focus interpretation on secure directional shifts, avoiding potentially inaccurate conclusions relating to specific water-table depths. The extent and diversity of the dataset highlighted that, at the taxonomic resolution applied, a majority of taxa had broad geographic distributions, though some morphotypes appeared to have restricted ranges
Innovative solutions to sticky situations: Antiadhesive strategies for treating bacterial infections
ABSTRACT
Bacterial adherence to host tissue is an essential process in pathogenesis, necessary for invasion and colonization and often required for the efficient delivery of toxins and other bacterial effectors. As existing treatment options for common bacterial infections dwindle, we find ourselves rapidly approaching a tipping point in our confrontation with antibiotic-resistant strains and in desperate need of new treatment options. Bacterial strains defective in adherence are typically avirulent and unable to cause infection in animal models. The importance of this initial binding event in the pathogenic cascade highlights its potential as a novel therapeutic target. This article seeks to highlight a variety of strategies being employed to treat and prevent infection by targeting the mechanisms of bacterial adhesion. Advancements in this area include the development of novel antivirulence therapies using small molecules, vaccines, and peptides to target a variety of bacterial infections. These therapies target bacterial adhesion through a number of mechanisms, including inhibition of pathogen receptor biogenesis, competition-based strategies with receptor and adhesin analogs, and the inhibition of binding through neutralizing antibodies. While this article is not an exhaustive description of every advancement in the field, we hope it will highlight several promising examples of the therapeutic potential of antiadhesive strategies.</jats:p
- âŠ