380 research outputs found
An alternative to suburban housing,
Massachusetts Institute of Technology. Dept. of Architecture. Thesis. 1971. B.Arch.Bibliography: leaves 56-57.by Joan R. Fleischnick and Lois J. Stern.B.Arch
Dust in the 55 Cancri planetary system
The presence of debris disks around 1-Gyr-old main sequence stars
suggests that an appreciable amount of dust may persist even in mature
planetary systems. Here we report the detection of dust emission from 55
Cancri, a star with one, or possibly two, planetary companions detected through
radial velocity measurements. Our observations at 850m and 450m imply
a dust mass of 0.0008-0.005 Earth masses, somewhat higher than that in the the
Kuiper Belt of our solar system. The estimated temperature of the dust grains
and a simple model fit both indicate a central disk hole of at least 10 AU in
radius. Thus, the region where the planets are detected is likely to be
significantly depleted of dust. Our results suggest that far-infrared and
sub-millimeter observations are powerful tools for probing the outer regions of
extrasolar planetary systems.Comment: 8 pages and 2 figures, to appear in the Astrophysical Journa
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Language Universals Engage Broca's Area
It is well known that natural languages share certain aspects of their design. For example, across languages, syllables like blif are preferred to lbif. But whether language universals are myths or mentally active constraints—linguistic or otherwise—remains controversial. To address this question, we used fMRI to investigate brain response to four syllable types, arrayed on their linguistic well-formedness (e.g., blif≻bnif≻bdif≻lbif, where ≻ indicates preference). Results showed that syllable structure monotonically modulated hemodynamic response in Broca's area, and its pattern mirrored participants' behavioral preferences. In contrast, ill-formed syllables did not systematically tax sensorimotor regions—while such syllables engaged primary auditory cortex, they tended to deactivate (rather than engage) articulatory motor regions. The convergence between the cross-linguistic preferences and English participants' hemodynamic and behavioral responses is remarkable given that most of these syllables are unattested in their language. We conclude that human brains encode broad restrictions on syllable structure
A randomized trial to determine the impact on compliance of a psychophysical peripheral cue based on the Elaboration Likelihood Model
Objective: Non-compliance in clinical studies is a significant issue, but causes remain unclear. Utilizing the Elaboration Likelihood Model of persuasion, this study assessed the psychophysical peripheral cue ‘Interactive Voice Response System (IVRS) call frequency’ on compliance. Methods: 71 participants were randomized to once daily (OD), twice daily (BID) or three times daily (TID) call schedules over two weeks. Participants completed 30-item cognitive function tests at each call. Compliance was defined as proportion of expected calls within a narrow window (± 30 min around scheduled time), and within a relaxed window (− 30 min to + 4 h). Data were analyzed by ANOVA and pairwise comparisons adjusted by the Bonferroni correction. Results: There was a relationship between call frequency and compliance. Bonferroni adjusted pairwise comparisons showed significantly higher compliance (p = 0.03) for the BID (51.0%) than TID (30.3%) for the narrow window; for the extended window, compliance was higher (p = 0.04) with OD (59.5%), than TID (38.4%). Conclusion: The IVRS psychophysical peripheral cue call frequency supported the ELM as a route to persuasion. The results also support OD strategy for optimal compliance. Models suggest specific indicators to enhance compliance with medication dosing and electronic patient diaries to improve health outcomes and data integrity respectively
Lymphocyte Subpopulation Number and Function in Infancy
Normal values for percentages of lymphocyte subpopulations and functional responses
to mitogen stimulation in infancy are not well established. In the present study,
lymphocyte subpopulations were examined in umbilical cord blood samples and in
peripheral blood samples drawn before 7 and 24 months of age (mean age 10.4 months)
from a healthy population of infants born in Tucson, Arizona. Results indicate
significant increases occurred from birth to later infancy in the percentages of total T
cells (CD3), T-cell subsets (CD4, CD8) and B cells (CD20). The CD4/CD8 ratio and the
functional responses to ConA and PWM mitogens significantly decreased from birth to
later infancy. PHA responsiveness did not show a significant change. Results from
cross-sectional analyses (n=271) were supported in a smaller longitudinal subset (n=37).
There were no detectable ethnic- or gender-related differences in cord blood or samples
obtained in later infancy. The normal values established in this study will be useful in
studies of immune-system maturation and in the clinical evaluation of newborns,
infants, and toddlers suspected of either acquired or congenital immune-deficiency
states
NuSTAR Spectroscopy of Multi-Component X-ray Reflection from NGC 1068
We report on observations of NGC1068 with NuSTAR, which provide the best
constraints to date on its ~keV spectral shape. We find no strong
variability over the past two decades, consistent with its Compton-thick AGN
classification. The combined NuSTAR, Chandra, XMM-Newton, and Swift-BAT
spectral dataset offers new insights into the complex reflected emission. The
critical combination of the high signal-to-noise NuSTAR data and a spatial
decomposition with Chandra allow us to break several model degeneracies and
greatly aid physical interpretation. When modeled as a monolithic (i.e., a
single N_H) reflector, none of the common Compton-reflection models are able to
match the neutral fluorescence lines and broad spectral shape of the Compton
reflection. A multi-component reflector with three distinct column densities
(e.g., N_H~1.5e23, 5e24, and 1e25 cm^{-2}) provides a more reasonable fit to
the spectral lines and Compton hump, with near-solar Fe abundances. In this
model, the higher N_H components provide the bulk of the Compton hump flux
while the lower N_H component produces much of the line emission, effectively
decoupling two key features of Compton reflection. We note that ~30% of the
neutral Fe Kalpha line flux arises from >2" (~140 pc), implying that a
significant fraction of the <10 keV reflected component arises from regions
well outside of a parsec-scale torus. These results likely have ramifications
for the interpretation of poorer signal-to-noise observations and/or more
distant objects [Abridged].Comment: Submitted to ApJ; 23 pages (ApJ format); 11 figures and 3 tables;
Comments welcomed
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Multicenter Study of Predictors of Disease Course in Alzheimer Disease (the "Predictors Study"). I. Study Design, Cohort Description, and Intersite Comparisons
Clinicians should be able to provide the patient with Alzheimer disease (AD) and the family with an accurate prediction of what to expect, but the variability in the rate of disease progression precludes this. In several previous studies, specific clinical signs such as muscular rigidity, myoclonus, and hallucinations or delusions were associated with rapid progression to a more severe stage of dementia or death. The 'Predictors Study,' a longitudinal study at three independent sites, was designed to develop a predictor model of the natural history of Alzheimer disease. The study was conducted at three study sites, New York, Baltimore, and Boston in a cohort of 224 patients with early probable AD. This article describes the design and implementation of the Predictors Study, and compares features of the study cohort at baseline across sites. Patients were all at the mild stage of disease at entry and were relatively comparable across sites. Extrapyramidal signs and delusions were common, but myoclonus was rarely observed
Accessing Justice II: A Model for Providing Counsel to New York Immigrants in Removal Proceedings
The New York Immigrant Representation Study (“NYIR Study”) is a two-year project of the Study Group on Immigrant Representation to analyze and ameliorate the immigrant representation crisis—the acute shortage of qualified attorneys willing and able to represent indigent immigrants facing deportation. The crisis has reached epic proportions in New York and shows no signs of abating.
In its year-one report (issued in the fall of 2011), the NYIR Study analyzed the empirical evidence regarding the nature and scope of the immigrant representation crisis. In that report, we documented how many New Yorkers—27 percent of those not detained and 60 percent of those who were detained—face deportation, and the prospect of permanent exile from families, homes and livelihoods, without any legal representation whatsoever. These unrepresented individuals are often held in detention and include many lawful permanent residents (green card holders), asylees and refugees, victims of domestic violence, and other classes of vulnerable immigrants with deep ties to New York. The study confirmed that the impact of having counsel cannot be overstated: people facing deportation in New York immigration courts with a lawyer are 500 percent as likely to win their cases as those without representation. While, at one end, nondetained immigrants with lawyers have successful outcomes 74 percent of the time, those on the other end, without counsel and who were detained, prevailed a mere 3 percent of the time.
In its second year, the NYIR Study convened a panel of experts to use the data from the year-one report to develop ambitious, yet realistic, near- to medium-term ways to mitigate the worst aspects of the immigrant representation crisis here in New York. The year-two analysis and proposals are set forth in detail here, in the NYIR Study Report: Part II.
A comprehensive solution to the nationwide immigrant representation crisis will require federal action. However, such federal action does not appear on the horizon. Meanwhile, the costs of needless deportations are felt most acutely in places like New York, with vibrant and vital immigrant communities. In addition to the injustice of seeing New Yorkers deported simply because they lack access to counsel, the impact of these deportations on the shattered New York families left behind is devastating. Moreover, the local community then bears the cost of these deportations in very tangible ways: when splintered families lose wage-earning members, they become dependent on a variety of City and State safety net programs to survive; the foster care system must step in when deportations cause the breakdown of families; and support networks to families and children must accommodate the myriad difficulties that result when federal policies are enforced without regard for local concerns. Put simply, the City and State of New York bear a heavy cost as a result of the immigrant representation crisis
Total Fume and Metal Concentrations during Welding in Selected Factories in Jeddah, Saudi Arabia
Welding is a major industrial process used for joining metals. Occupational exposure to welding fumes is a serious occupational health problem all over the world. The degree of risk to welder’s health from fumes depends on composition, concentration, and the length of exposure. The aim of this study was to investigate workers’ welding fume exposure levels in some industries in Jeddah, Saudi Arabia. In each factory, the air in the breathing zone within 0.5 m from welders was sampled during 8-hour shifts. Total particulates, manganese, copper, and molybdenum concentrations of welding fumes were determined. Mean values of eight-hour average particulate concentrations measured during welding at the welders breathing zone were 6.3 mg/m3 (Factory 1), 5.3 mg/m3 (Factory 2), 11.3 mg/m3 (Factory 3), 6.8 mg/m3 (Factory 4), 4.7 mg/m3 (Factory 5), and 3.0 mg/m3 (Factory 6). Mean values of airborne manganese, copper, and molybdenum levels measured during welding were in the range of 0.010 mg/m3–0.477 mg/m3, 0.001 mg/m3–0.080 mg/m3 and 0.001 mg/m3–0.058 mg/m3 respectively. Mean values of calculated equivalent exposure values were: 1.50 (Factory 1), 1.56 (Factory 2), 5.14 (Factory 3), 2.21 (Factory 4), 2.89 (Factory 5), and 1.20 (Factory 6). The welders in factories 1, 2, 3, and 4 were exposed to welding fume concentration above the SASO limit value, which may increase the risk of respiratory health problems
Mercury in the marine environment of the Canadian Arctic: Review of recent findings
AbstractThis review summarizes data and information which have been generated on mercury (Hg) in the marine environment of the Canadian Arctic since the previous Canadian Arctic Contaminants Assessment Report (CACAR) was released in 2003. Much new information has been collected on Hg concentrations in marine water, snow and ice in the Canadian Arctic. The first measurements of methylation rates in Arctic seawater indicate that the water column is an important site for Hg methylation. Arctic marine waters were also found to be a substantial source of gaseous Hg to the atmosphere during the ice-free season. High Hg concentrations have been found in marine snow as a result of deposition following atmospheric mercury depletion events, although much of this Hg is photoreduced and re-emitted back to the atmosphere. The most extensive sampling of marine sediments in the Canadian Arctic was carried out in Hudson Bay where sediment total Hg (THg) concentrations were low compared with other marine regions in the circumpolar Arctic. Mass balance models have been developed to provide quantitative estimates of THg fluxes into and out of the Arctic Ocean and Hudson Bay.Several recent studies on Hg biomagnification have improved our understanding of trophic transfer of Hg through marine food webs. Over the past several decades, Hg concentrations have increased in some marine biota, while other populations showed no temporal change. Marine biota also exhibited considerable geographic variation in Hg concentrations with ringed seals, beluga and polar bears from the Beaufort Sea region having higher Hg concentrations compared with other parts of the Canadian Arctic. The drivers of these variable patterns of Hg bioaccumulation, both regionally and temporally, within the Canadian Arctic remain unclear. Further research is needed to identify the underlying processes including the interplay between biogeochemical and food web processes and climate change
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