1,752 research outputs found
Interactive Supercomputing with MIT Matlab
This paper describes MITMatlab, a system that enables users of supercomputers or networked PCs to work on large data sets within Matlab transparently. MITMatlab is based on the Parallel Problems Server (PPServer), a standalone 'linear algebra server' that provides a mechanism for running distributed memory algorithms on large data sets. The PPServer and MITMatlab enable high-performance interactive supercomputing. With such a tool, researchers can now use Matlab as more than a prototyping tool for experimenting with small problems. Instead, MITMatlab makes is possible to visualize and operate interactively on large data sets. This has implications not only in supercomputing, but for Artificial Intelligence applicatons such as Machine Learning, Information Retrieval and Image Processing
A preliminary investigation of the AUDIT and DUDIT in comparison to biomarkers for alcohol and drug use among HIV-infected clinic attendees in Cape Town, South Africa
Objective: There is growing concern about the effect of substance use on HIV treatment outcomes. The study objectives included: (i) evaluating whether the use of validated questionnaires (AUDIT and DUDIT) provide useful and consistent information of alcohol and drug consumption when compared with the use of biomarkers of alcohol in (urine and hair) and drugs in (urine) and (ii) assessing the feasibility of using self-report measures compared with urine and hair tests.Method: Participants were HIV positive patients attending an HIV community health clinic in Kraaifontein, Cape Town. Hair and urine samples were collected and analysed for alcohol, in Fatty Acid Ethyl Esters (FAEE) and in Ethyl Glucuronide and (EtG), and drugs. Biological markers were compared with self-report measures of alcohol and drug consumption in terms of sensitivity, specificity. Forty-three participants completedthe self-report measures, while 30 provided hair and urine samples. Results: On the AUDIT, 18 (41.9%) participants screened positive for harmful and hazardous drinking and 13 (30.2%) participants on the DUDIT screened positive for having a drug-related problem. Two of 30 participants (7%) tested positive for alcohol abuse on FAEE analysis. For EtG, 6 of 24 (25%) participants tested positive for alcohol abuse. On hair drug analysis, all 30 participants tested negative for cannabis, amphetamines, opiates, cocaine, PCP and methaqualone. On the urinalysis, 1of 30 participants tested positive for cannabis and everyone tested negative for all otherdrugs included in the screening.Conclusion: Substance use among patients attending HIV clinics appears to be a problem, especially alcohol. Self-report measures seem to be a more cost effective option for screening of alcohol and drug abuse inresource poor settings
A new fireworm (Amphinomidae) from the Cretaceous of Lebanon identified from three-dimensionally preserved myoanatomy
© 2015 Parry et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The attached file is the published version of the article
Reaching Backward and Stretching Forward: Teaching for Transfer in Law School Clinics
In thinking about education, teachers may spend more time considering what to teach than how to teach. Unfortunately, traditional teaching techniques have limited effectiveness in their ability to help students retain and apply the knowledge either in later classes or in their professional work. What, then, is the value of our teaching efforts if students are unable to transfer the ideas and skills they have learned to later situations? Teaching for transfer is important to the authors of this article, four clinical professors and one psychologist. The purpose of this article is to provide an introduction to some of the techniques that can improve the transfer of teaching. While this article focuses on applications in the law clinic, the procedures can be profitably used in doctrinal classes as well. It is the goal of the authors of this article to help you improve your teaching so that your students will understand, remember, and be able to later use what you teach them. While this may appear overly ambitious, we are not selling snake oil. Rather, we are relying on established tenets of psychology and pedagogy that have proved successful in other areas of learning.In the first section, psychologist Shaun Archer will summarize the latest research results on memory and how to best teach so that students can retain and use information. Before transferring information or ideas from a class to a new situation, one must first anchor the concept in the mind. To do this, the student must attach the new information to the existing scaffolding in the studentâs memory. Attached to the wrong structure, the new information cannot easily be used in a later application. For example, if you are told that both a successful asylum application and chlorophyll contain five elements, you might be momentarily chagrined since the word âelementsâ is used in two very different contexts. Your mind must travel down various discrete neural pathways to make correct sense of the use of the word in each phrase. This insight from psychology is the core of teaching for transfer. Tonya Kowalski will then introduce the principles of teaching for transfer, emphasizing âreaching backwardâ and âstretching forwardâ techniques. She will then suggest applications of these procedures in clinical teaching. In reaching backward, a student thinks back to past experiences or concepts to find existing mental scaffolding that can be used to bear the weight and provide an accessible resting place for the new material that is being taught. In stretching forward, a student consciously envisions potential future applications of the material being learned. Colleen Shanahan will demonstrate backward-reaching transfer techniques for teaching students skills and knowledge, using the examples of initial client interviews, soliciting facts from witnesses, researching eviction procedures, and developing an effective oral advocacy style. Jim Kelly will provide specific examples of stretching-forward transfer techniques. These range from âhugging,â identifying very similar future applications, such as the business record litany, to âbridging,â preparing students to be able to use new foundational skills or knowledge in complex and extremely varied situations
A preliminary investigation of the AUDIT and DUDIT in comparison to biomarkers for alcohol and drug use among HIV-infected clinic attendees in Cape Town, South Africa
Constraining mass ratio and extinction in the FU Orionis binary system with infrared integral field spectroscopy
We report low resolution near infrared spectroscopic observations of the
eruptive star FU Orionis using the Integral Field Spectrograph Project 1640
installed at the Palomar Hale telescope. This work focuses on elucidating the
nature of the faint source, located 0.5" south of FU Ori, and identified in
2003 as FU Ori S. We first use our observations in conjunction with published
data to demonstrate that the two stars are indeed physically associated and
form a true binary pair. We then proceed to extract J and H band
spectro-photometry using the damped LOCI algorithm, a reduction method tailored
for high contrast science with IFS. This is the first communication reporting
the high accuracy of this technique, pioneered by the Project 1640 team, on a
faint astronomical source. We use our low resolution near infrared spectrum in
conjunction with 10.2 micron interferometric data to constrain the infrared
excess of FU Ori S. We then focus on estimating the bulk physical properties of
FU Ori S. Our models lead to estimates of an object heavily reddened, A_V
=8-12, with an effective temperature of ~ 4000-6500 K . Finally we put these
results in the context of the FU Ori N-S system and argue that our analysis
provides evidence that FU Ori S might be the more massive component of this
binary syste
A New High Contrast Imaging Program at Palomar Observatory
We describe a new instrument that forms the core of a long-term high contrast
imaging program at the 200-inch Hale Telescope at Palomar Observatory. The
primary scientific thrust is to obtain images and low-resolution spectroscopy
of brown dwarfs and young Jovian mass exoplanets in the vicinity of stars
within 50 parsecs of the Sun. The instrument is a microlens-based integral
field spectrograph integrated with a diffraction limited, apodized-pupil Lyot
coronagraph, mounted behind the Palomar adaptive optics system. The
spectrograph obtains imaging in 23 channels across the J and H bands (1.06 -
1.78 microns). In addition to obtaining spectra, this wavelength resolution
allows suppression of the chromatically dependent speckle noise, which we
describe. We have recently installed a novel internal wave front calibration
system that will provide continuous updates to the AO system every 0.5 - 1.0
minutes by sensing the wave front within the coronagraph. The Palomar AO system
is undergoing an upgrade to a much higher-order AO system ("PALM-3000"): a
3388-actuator tweeter deformable mirror working together with the existing
241-actuator mirror. This system will allow correction with subapertures as
small as 8cm at the telescope pupil using natural guide stars. The coronagraph
alone has achieved an initial dynamic range in the H-band of 2 X 10^-4 at 1
arcsecond, without speckle noise suppression. We demonstrate that spectral
speckle suppression is providing a factor of 10-20 improvement over this
bringing our current contrast at an arcsecond to ~2 X 10^-5. This system is the
first of a new generation of apodized pupil coronagraphs combined with
high-order adaptive optics and integral field spectrographs (e.g. GPI, SPHERE,
HiCIAO), and we anticipate this instrument will make a lasting contribution to
high contrast imaging in the Northern Hemisphere for years.Comment: Accepted to PASP: 12 pages, 12 figure
Finitely presented wreath products and double coset decompositions
We characterize which permutational wreath products W^(X)\rtimes G are
finitely presented. This occurs if and only if G and W are finitely presented,
G acts on X with finitely generated stabilizers, and with finitely many orbits
on the cartesian square X^2. On the one hand, this extends a result of G.
Baumslag about standard wreath products; on the other hand, this provides
nontrivial examples of finitely presented groups. For instance, we obtain two
quasi-isometric finitely presented groups, one of which is torsion-free and the
other has an infinite torsion subgroup.
Motivated by the characterization above, we discuss the following question:
which finitely generated groups can have a finitely generated subgroup with
finitely many double cosets? The discussion involves properties related to the
structure of maximal subgroups, and to the profinite topology.Comment: 21 pages; no figure. To appear in Geom. Dedicat
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