1,066 research outputs found
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Investigating the Foreign Language Needs of Professional School Students in International Affairs: A Case Study
On-going demographic changes and increasing globalization have challenged professional schools to prepare students for the plurilinguistic and pluricultural realities of the workplace both within and across national boundaries. Given these evolving workplace realities, professional schools may need to re-assess the degree to which their studentsâ career needs are being met by existing language programs, so that policy and resources can be adjusted accordingly. The current inquiry reports on a large-scale assessment designed to investigate the foreign language needs of students in the School of International and Public Affairs (SIPA) at Columbia University and to evaluate the degree to which these needs are being addressed. Recognizing that different stakeholders may have opposing perceptions of foreign language needs, this study utilized a conceptual model of needs assessment that surveyed multiple sources of data within and across a variety of stakeholder groups. These perceived needs were then examined and compared. The findings showed a disparity among the needs of the professional school students, foreign language instruction, and SIPAâs language policy. While these results were not entirely unexpected, they were highlighted by evidence from the different perspectives surveyed. The model of needs assessment used in this study served as an invaluable framework for examining the different dimensions of foreign language needs
New approach for precise computation of Lyman-alpha forest power spectrum with hydrodynamical simulations
Current experiments are providing measurements of the flux power spectrum from the Lyman-α forests observed in quasar spectra with unprecedented accuracy. Their interpretation in terms of cosmological constraints requires specific simulations of at least equivalent precision. In this paper, we present a suite of cosmological N-body simulations with cold dark matter and baryons, specifically aiming at modeling the low-density regions of the inter-galactic medium as probed by the Lyman-α forests at high redshift. The simulations were run using the GADGET-3 code and were designed to match the requirements imposed by the quality of the current SDSS-III/BOSS or forthcoming SDSS-IV/eBOSS data. They are made using either 2 Ă 7683 1 billion or 2 Ă 1923 14 million particles, spanning volumes ranging from (25 Mpc hâ1)3 for high-resolution simulations to (100 Mpc hâ1)3 for large-volume ones. Using a splicing technique, the resolution is further enhanced to reach the equivalent of simulations with 2 Ă 30723 58 billion particles in a (100 Mpc hâ1)3 box size, i.e. a mean mass per gas particle of 1.2 Ă 105Mâ hâ1. We show that the resulting power spectrum is accurate at the 2% level over the full range from a few Mpc to several tens of Mpc. We explore the effect on the one-dimensional transmitted-flux power spectrum of four cosmological parameters (ns, Ï8, Ωm and H0) and two astrophysical parameters (T0 and Îł) that are related to the heating rate of the intergalactic medium. By varying the input parameters around a central model chosen to be in agreement with the latest Planck results, we built a grid of simulations that allows the study of the impact on the flux power spectrum of these six relevant parameters. We improve upon previous studies by not only measuring the effect of each parameter individually, but also probing the impact of the simultaneous variation of each pair of parameters. We thus provide a full second-order expansion, including cross-terms, around our central model. We check the validity of the second-order expansion with independent simulations obtained either with different cosmological parameters or different seeds. Finally, a comparison to the one-dimensional Lyman-α forest power spectrum obtained with BOSS by [1] shows an excellent agreement
Tensions of Integration in Professional Formation: Investigating Development of Engineering Students\u27 Social and Technical Perceptions
Tensions of Integration in Professional Formation: Investigating Development of Engineering Students\u27 Social and Technical PerceptionsTwenty-first century engineers face incredible challenges and opportunities, many of which aresocially complex, transcending the traditional âtechnicalâ boundaries of engineering. Thetechnology produced by engineers must not only function as predicted by mathematical andtheoretical models but must also operate beneficially and seamlessly in complex social contexts.In this sense, engineers must embody an integrated social and technical â or sociotechnical âidentity rather than a dualistic social/technical one.A growing body of scholarship has discussed how dominant cultures of engineering shapestudentsâ and professionalsâ understandings of social and technical dimensions of their work.Further, engineering education research has advanced understanding of how engineering identityis formed by external, structural forces. Yet, from a psychological perspective, we know littleabout how engineering students come to perceive and embody their identities as engineers,especially in relation to social and technical dimensions of these identities. Thus, we organizedthis study around the following research questions.RQ0: How do students psychologically experience identity trajectories of becoming engineers?RQ1: How do students perceive the social and technical features of engineering identity?RQ2: How do students internally experience their identities as engineers, particularly with regard to social and technical dimensions of these identities?RQ3: How do social and technical perceptions of their engineering identity develop and change in the course of the engineering curriculum or in the transition to the workplace?To respond to these research questions, we have conducted two longitudinal studies usinginterpretative phenomenological analysis (IPA). One study focused on graduating seniors as theytransitioned into the workplace, and the second study focused on first-year students transitioningto engineering degree coursework. These investigations produced robust and nuancedunderstanding of studentsâ engineering identity trajectories throughout and beyond thecurriculum. These findings are being leveraged in order to provide our initial understanding in athematic analysis on sophomore engineering students.Thus far, the findings of the investigation highlight the complexity of becoming both engineers,specifically by demonstrating a somewhat contradictory relationship between what participantsperceived to be engineering and how they actually embodied an engineering-self. They furtherdemonstrate the manifold ways that participants realized and prioritized identities outside ofengineering and how these multiple selves interacted in ways that affected their engineeringidentities. Additionally, findings for both male and female groups suggest that somepsychological patterns might be related to gender. In sum, the findings depict a complex pictureof engineering-students-turned-engineers as whole persons. By focusing on how engineeringidentity development is embodied, the findings generate multiple theoretical insights that bearrelevance for engineering education research and provocative implications that bear significancefor engineering educators, students, and employers
Interleukin-1 plays a major role in vascular inflammation and atherosclerosis in male apolipoprotein E-knockout mice
Objective: To examine the role of the balance between interleukin (IL)-1 and IL-1 receptor antagonist (IL-1Ra) in atherosclerosis and vascular inflammation. Methods: Transgenic (Tg) mice overexpressing either secreted IL-1Ra or intracellular IL-1Ra1 as well as IL-1Ra-deficient mice (IL-1Ra â/â) were crossed with apolipoprotein E-deficient mice (ApoE â/â). Results: In males fed a cholesterol-rich diet for 10 weeks, average atherosclerotic lesion area within aortic roots was significantly decreased in ApoE â/â secreted IL-1Ra Tg (â47%) and ApoE â/â intracellular IL-1Ra1 Tg (â40%) mice as compared to ApoE â/â non-Tg controls. The extent of sudanophilic lesions was reduced within the thoraco-abdominal aorta in ApoE â/â secreted IL-1Ra (â53%) and ApoE â/â intracellular IL-1Ra1 (â67%) Tg mice. In parallel experiments, we observed early mortality and illness among double deficient mice, whereas ApoE â/â IL-1Ra +/+ and ApoE +/+ IL-1Ra â/â mice were apparently healthy. After 7 weeks of diet, ApoE â/â IL-1Ra â/â mice exhibited massive aortic inflammation with destruction of the vascular architecture, but no signs of atherosclerosis. ApoE â/â IL-1Ra +/+ had atherosclerosis and a moderate inflammatory reaction, whereas ApoE +/+ IL-1Ra â/â mice were free of vascular lesions. Macrophages were present in large amounts within inflammatory lesions in the adventitia of ApoE â/â IL-1Ra â/â mice. Conclusion: Our results demonstrate that the IL-1/IL-1Ra ratio plays a critical role in the pathogenic mechanisms leading to vascular inflammation and atherosclerosis in ApoE â/â mic
Constraint on neutrino masses from SDSS-III/BOSS Ly-alpha forest and other cosmological probes
International audienceWe present constraints on the parameters of the CDM cosmologicalmodel in the presence of massive neutrinos, using the one-dimensionalLy forest power spectrum obtained with the Baryon OscillationSpectroscopic Survey (BOSS) of the Sloan Digital Sky Survey (SDSS) byPalanque-Delabrouille et al. (2013), complemented by additional cosmologicalprobes. The interpretation of the measured Ly spectrum is done using asecond-order Taylor expansion of the simulated power spectrum. BOSS Ly data alone provide better bounds than previous Ly results,but are still poorly constraining, especially for the sum of neutrino masses, for which we obtain an upper bound of 1.1~eV (95\% CL), includingsystematics for both data and simulations. Ly constraints onCDM parameters and neutrino masses are compatible with CMB bounds fromthe Planck collaboration. Interestingly, the combination of Ly with CMBdata reduces the uncertainties significantly, due to very different directionsof degeneracy in parameter space, leading to the strongest cosmological boundto date on the total neutrino mass, ~eV at 95\% CL (with abest-fit in zero). Adding recent BAO results further tightens this constraintto ~eV at 95\% CL. This bound is nearly independent of thestatistical approach used, and of the different combinations of CMB and BAOdata sets considered in this paper in addition to Ly. Given themeasured values of the two squared mass differences , this resulttends to favor the normal hierarchy scenario against the inverted hierarchyscenario for the masses of the active neutrino species
Recurrence after laparoscopic and open Nissen fundoplication
Background: Laparoscopic Nissen fundoplication as treatment for gastroesophageal reflux disease (GERD) in adults has a reported recurrence rate of 2â17%. We investigated the rates and mechanisms of failure after laparoscopic Nissen fundoplication in children. Methods: All patients who underwent a laparoscopic Nissen fundoplication for GERD and who subsequently required a redo Nissen were reviewed ( n = 15). The control group consisted of the most recent 15 patients who developed recurrent GER after an open Nissen, fundoplication. Results: Between 1994 and 2000, laparoscopic Nissen fundoplication was performed in 179 patients. Fifteen patients (8.7%) underwent revision. The mechanisms of failure were herniation in four patients, wrap dehiscence in four, a too-short wrap in three, a loosened wrap in two, and other reasons in two. The reoperation was performed laparoscopically in five patients (33%). The failure mechanisms were different in the open patients: eight were due to slipped wraps; three to dehiscences; and two to herniations. Conclusion: The failure rate after laparoscopic Nissen is acceptably low. A redo laparoscopic Nissen can be performed safely after an initial laparoscopic approach.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41361/1/464_2002_Article_8515.pd
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Isolation of Angola-like Marburg virus from Egyptian rousette bats from West Africa.
Marburg virus (MARV) causes sporadic outbreaks of severe Marburg virus disease (MVD). Most MVD outbreaks originated in East Africa and field studies in East Africa, South Africa, Zambia, and Gabon identified the Egyptian rousette bat (ERB; Rousettus aegyptiacus) as a natural reservoir. However, the largest recorded MVD outbreak with the highest case-fatality ratio happened in 2005 in Angola, where direct spillover from bats was not shown. Here, collaborative studies by the Centers for Disease Control and Prevention, Njala University, University of California, Davis USAID-PREDICT, and the University of Makeni identify MARV circulating in ERBs in Sierra Leone. PCR, antibody and virus isolation data from 1755 bats of 42 species shows active MARV infection in approximately 2.5% of ERBs. Phylogenetic analysis identifies MARVs that are similar to the Angola strain. These results provide evidence of MARV circulation in West Africa and demonstrate the value of pathogen surveillance to identify previously undetected threats
Baryon Acoustic Oscillations in the Ly{\alpha} forest of BOSS DR11 quasars
We report a detection of the baryon acoustic oscillation (BAO) feature in the
flux-correlation function of the Ly{\alpha} forest of high-redshift quasars
with a statistical significance of five standard deviations. The study uses
137,562 quasars in the redshift range from the Data Release
11 (DR11) of the Baryon Oscillation Spectroscopic Survey (BOSS) of SDSS-III.
This sample contains three times the number of quasars used in previous
studies. The measured position of the BAO peak determines the angular distance,
and expansion rate, , both on a scale set by the sound
horizon at the drag epoch, . We find
and
where . The optimal
combination, is determined with a precision of
. For the value , consistent with the CMB power
spectrum measured by Planck, we find
and . Tests with mock
catalogs and variations of our analysis procedure have revealed no systematic
uncertainties comparable to our statistical errors. Our results agree with the
previously reported BAO measurement at the same redshift using the
quasar-Ly{\alpha} forest cross-correlation. The auto-correlation and
cross-correlation approaches are complementary because of the quite different
impact of redshift-space distortion on the two measurements. The combined
constraints from the two correlation functions imply values of and
that are, respectively, 7% low and 7% high compared to the
predictions of a flat CDM cosmological model with the best-fit Planck
parameters. With our estimated statistical errors, the significance of this
discrepancy is .Comment: Accepted for publication in A&A. 17 pages, 18 figure
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