5,600 research outputs found
Gentrification in (re)construction: Talca's neighbourhoods post 2010 earthquake
PURPOSE: This paper aims to explore the complex relationship between post-earthquake
reconstruction processes and gentrification in neighborhoods of intermediate cities,
calling on the critical role of recovery strategies in altering neighborhoods physical and
social urban structure identities.
DESIGN/METHODOLOGY/APPROACH: The paper uses a case study; the reconstruction process
of the neighborhoods post 2010 earthquake in Talca, Chile and analyses in a six year
timeline its socio-spatial changes. The latter based on mixed methods; primary data from
strategic interviews with key stakeholders, cadasters of land value and real estate housing
projects and neighborhood polls, and secondary data from official documents such as
plans and policies.
FINDINGS: Findings suggest patterns of incipient gentrification are an outcome of the
reconstruction strategies. Acknowledging the intricate interplay among urban neoliberal
conditions, historical heritage and identities, and post disaster recovery, inadequate
housing subsidies and normative plans are causing the displacement of hundreds of
historical residents and resistance, arrival of newcomers with higher debt capacity in new
housing typologies, and increasing land value. Process related to neoliberal politics of
state led new-build gentrification.
ORIGINALITY/VALUE: Gentrification and reconstruction are both processes that modify urban
structures, society and perceptions, and yet their socio spatial effects have never been
studied in a cumulative and integrated manner, even more, in intermediate cities. The
value is to rethink the critical role of recovery strategies in halting and containing
gentrification in fast transforming secondary cities
Optical and Infrared Photometry of the Unusual Type Ia Supernova 2000cx
We present optical and infrared photometry of the unusual Type Ia supernova
2000cx. With the data of Li et al. (2001) and Jha (2002), this comprises the
largest dataset ever assembled for a Type Ia SN, more than 600 points in
UBVRIJHK. We confirm the finding of Li et al. regarding the unusually blue B-V
colors as SN 2000cx entered the nebular phase. Its I-band secondary hump was
extremely weak given its B-band decline rate. The V minus near infrared colors
likewise do not match loci based on other slowly declining Type Ia SNe, though
V-K is the least ``abnormal''. In several ways SN 2000cx resembles other slow
decliners, given its B-band decline rate (Delta m_15(B) = 0.93), the appearance
of Fe III lines and weakness of Si II in its pre-maximum spectrum, the V-K
colors and post-maximum V-H colors. If the distance modulus derived from
Surface Brightness Fluctuations of the host galaxy is correct, we find that the
rate of light increase prior to maximum, the characteristics of the bolometric
light curve, and the implied absolute magnitude at maximum are all consistent
with a sub-luminous object with Delta m_15(B) ~ 1.6-1.7 having a higher than
normal kinetic energy.Comment: 46 pages, 17 figures, to be published in Publications of the
Astronomical Society of the Pacifi
Low Arousal Threshold Estimation Predicts Failure of Mandibular Advancement Devices in Obstructive Sleep Apnea Syndrome
Introduction: The treatment of choice for obstructive sleep apnea syndrome (OSAS) is continuous positive airway pressure (CPAP). However, CPAP is usually poorly tolerated and mandibular advancement devices (MADs) are an alternative innovative therapeutic approach. Uncertainty still remains as to the most suitable candidates for MAD. Herein, it is hypothesized that the presence of low arousal threshold (low ArTH) could be predictive of MAD treatment failure.
Methods: A total of 32 consecutive patients, with OSAS of any severity, who preferred an alternate therapy to CPAP, were treated with a tailored MAD aimed at obtaining 50% of their maximal mandibular advancement. Treatment response after 6 months of therapy was defined as AHI 58.3%.
Results: There were 25 (78.1%) responders (p-value < 0.01) at 6 months. Thirteen patients (40.6%) in the non-severe group reached AHI lower than 5 events per hour. MAD treatment significantly reduced the median AHI in all patients from a median value of 22.5 to 6.5 (74.7% of reduction, p-value < 0.001). The mandibular advancement device reduced AHI, whatever the disease severity. A significant higher reduction of Delta AHI, after 6 months of treatment, was found for patients without low ArTH.
Conclusions: Low ArTH at baseline was associated with a poorer response to MAD treatment and a lower AHI reduction at 6 months. A non-invasive assessment of Low ArTH can be performed through the Edwards' score, which could help to identify an endotype with a lower predicted response to oral appliances in a clinical setting
Type Ia supernova SN 2003du: optical observations
UBVRI photometry and optical spectra of type Ia supernova SN 2003du obtained
at the Indian Astronomical Observatory for nearly a year since discovery are
presented.
The apparent magnitude at maximum was B=13.53 +/- 0.02 mag, and the colour
(B-V) = -0.08 +/- 0.03 mag. The luminosity decline rate, Delta(m_{15}(B)) =
1.04 +/- 0.04 mag indicates an absolute B magnitude at maximum of M_B = -19.34
+/- 0.3 mag and the distance modulus to the parent galaxy as mu=32.89 +/-
0.4.The light curve shapes are similar, though not identical, to those of SNe
1998bu and 1990N, both of which had luminosity decline rates similar to that of
SN 2003du and occurred in spiral galaxies. The peak bolometric luminosity
indicates that 0.9 Msun mass of 56Ni was ejected by the supernova. The spectral
evolution and the evolution of the Si II and Ca II absorption velocities
closely follows that of SN 1998bu, and in general, is within the scatter of the
velocities observed in normal type Ia supernovae.
The spectroscopic and photometric behaviour of SN 2003du is quite typical for
SNe Ia in spirals.
A high velocity absorption component in the Ca II (H & K) and IR-triplet
features, with absorption velocities of ~20,000 km/s and ~22,000 km/s
respectively, is detected in the pre-maximum spectra of days -11 and -7.Comment: 10 pages, 10 figures; Accepted for publication in A&
Telehealth and Mobile Health Applied To IntegratedBehavioral Care: OpportunitiesFor Progress In New Hampshire
This paper is an accompanying document to a webinar delivered on May 16, 2017, for the New Hampshire Citizens Health Initiative (Initiative). As integrated behavioral health efforts in New Hampshire gain traction, clinicians, administrators, payers, and policy makers are looking for additional efficiencies in delivering high quality healthcare. Telehealth and mobile health (mHealth) have the opportunity to help achieve this while delivering a robust, empowered patient experience.
The promise of video-based technology was first made in 1964 as Bell Telephone shared its Picturephone® with the world. This was the first device with audio and video delivered in an integrated technology platform. Fast-forward to today with Skype, FaceTime, and webinar tools being ubiquitous in our personal and business lives, but often slow to be adopted in the delivery of medicine.
Combining technology-savvy consumers with New Hampshire’s high rate of electronic health record (EHR) technology adoption, a fairly robust telecommunications infrastructure, and a predominately rural setting, there is strong foundation for telehealth and mHealth expansion in New Hampshire’s integrated health continuum
Three-dimensional modeling of Type Ia supernovae - The power of late time spectra
Late time synthetic spectra of Type Ia supernovae, based on three-dimensional
deflagration models, are presented. We mainly focus on one
model,"c3_3d_256_10s", for which the hydrodynamics (Roepke 2005) and
nucleosynthesis (Travaglio et al. 2004) was calculated up to the homologous
phase of the explosion. Other models with different ignition conditions and
different resolution are also briefly discussed. The synthetic spectra are
compared to observed late time spectra. We find that while the model spectra
after 300 to 500 days show a good agreement with the observed Fe II-III
features, they also show too strong O I and C I lines compared to the observed
late time spectra. The oxygen and carbon emission originates from the
low-velocity unburned material in the central regions of these models. To get
agreement between the models and observations we find that only a small mass of
unburned material may be left in the center after the explosion. This may be a
problem for pure deflagration models, although improved initial conditions, as
well as higher resolution decrease the discrepancy. The relative intensity from
the different ionization stages of iron is sensitive to the density of the
emitting iron-rich material. We find that clumping, with the presence of low
density regions, is needed to reproduce the observed iron emission, especially
in the range between 4000 and 6000 AA. Both temperature and ionization depend
sensitively on density, abundances and radioactive content. This work therefore
illustrates the importance of including the inhomogeneous nature of realistic
three-dimensional explosion models. We briefly discuss the implications of the
spectral modeling for the nature of the explosion.Comment: 20 pages, 9 figures, resolution of Fig 1 is reduced to meet astro-ph
file size restriction, submitted to A&
Type Ia Supernovae as Sites of p-process: Two-Dimensional Models Coupled to Nucleosynthesis
We explore SNe Ia as p-process sites in the framework of two-dimensional SN
Ia delayed detonation and pure deflagration models. The WD precursor is assumed
to have reached the Chandrasekhar mass in a binary system by mass accretion
from a giant/main sequence companion. We use enhanced s-seed distributions,
obtained from a sequence of thermal pulse instabilities both in the AGB phase
and in the accreted material. We apply the tracer-particle method to
reconstruct the nucleosynthesis by the thermal histories of Lagrangian
particles, passively advected in the hydrodynamic calculations. For each
particle we follow the explosive nucleosynthesis with a detailed network for
all isotopes up to 209Bi. We find that SNe Ia can produce a large amount of
p-nuclei, both the light p-nuclei below A=120 and the heavy-p nuclei, at quite
flat average production factors, tightly related to the s-process seed
distribution. For the first time, we find a stellar source able to produce
both, light and heavy p-nuclei almost at the same level as 56Fe, including the
very debated neutron magic 92,94Mo and 96,98Ru. We also find that there is an
important contribution from p-process nucleosynthesis to the s-only nuclei
80Kr, 86Sr, to the neutron magic 90Zr, and to the neutron-rich 96Zr. Finally,
we investigate the metallicity effect on p-process. Starting with different
s-process seed distributions, for two metallicities Z = 0.02 and Z = 0.001,
running SNe Ia models with different initial composition, we estimate that SNe
Ia can contribute to, at least, 50% of the solar p-process composition.Comment: 62 pages, 14 figures, 5 tables, ApJ in pres
The ESSENCE Supernova Survey: Survey Optimization, Observations, and Supernova Photometry
We describe the implementation and optimization of the ESSENCE supernova
survey, which we have undertaken to measure the equation of state parameter of
the dark energy. We present a method for optimizing the survey exposure times
and cadence to maximize our sensitivity to the dark energy equation of state
parameter w=P/rho c^2 for a given fixed amount of telescope time. For our
survey on the CTIO 4m telescope, measuring the luminosity distances and
redshifts for supernovae at modest redshifts (z~0.5 +- 0.2) is optimal for
determining w. We describe the data analysis pipeline based on using reliable
and robust image subtraction to find supernovae automatically and in near
real-time. Since making cosmological inferences with supernovae relies
crucially on accurate measurement of their brightnesses, we describe our
efforts to establish a thorough calibration of the CTIO 4m natural photometric
system. In its first four years, ESSENCE has discovered and spectroscopically
confirmed 102 type Ia SNe, at redshifts from 0.10 to 0.78, identified through
an impartial, effective methodology for spectroscopic classification and
redshift determination. We present the resulting light curves for the all type
Ia supernovae found by ESSENCE and used in our measurement of w, presented in
Wood-Vasey et al, 2007.Comment: Submitted to ApJ. Companion paper to Wood-Vasey et al (2007).
Electronic tables available at http://www.ctio.noao.edu/essence/wresult
The Rise Time of Type Ia Supernovae from the Supernova Legacy Survey
We compare the rise times of nearby and distant Type Ia supernovae (SNe Ia)
as a test for evolution using 73 high-redshift spectroscopically-confirmed SNe
Ia from the first two years of the five year Supernova Legacy Survey (SNLS) and
published observations of nearby SN. Because of the ``rolling'' search nature
of the SNLS, our measurement is approximately 6 times more precise than
previous studies, allowing for a more sensitive test of evolution between
nearby and distant supernovae. Adopting a simple early-time model (as in
previous studies), we find that the rest-frame rise times for a fiducial SN
Ia at high and low redshift are consistent, with values
and
days, respectively; the statistical significance of this difference is only 1.4
\sg . The errors represent the uncertainty in the mean rather than any
variation between individual SN. We also compare subsets of our high-redshift
data set based on decline rate, host galaxy star formation rate, and redshift,
finding no substantive evidence for any subsample dependence.Comment: Accepted for publication in AJ; minor changes (spelling and
grammatical) to conform with published versio
The effect of progenitor age and metallicity on luminosity and 56Ni yield in Type Ia supernovae
Timmes, Brown & Truran found that metallicity variations could theoretically
account for a 25% variation in the mass of 56Ni synthesized in Type Ia
supernovae (SNe Ia), and thus account for a large fraction of the scatter in
observed SN Ia luminosities. Higher-metallicity progenitors are more
neutron-rich, producing more stable burning products relative to radioactive
56Ni. We develop a new method for estimating bolometric luminosity and 56Ni
yield in SNe Ia and use it to test the theory with data from the Supernova
Legacy Survey. We find that the average 56Ni yield does drop in SNe Ia from
high metallicity environments, but the theory can only account for 7%--10% of
the dispersion in SN Ia 56Ni mass, and thus luminosity. This is because the
effect is dominant at metallicities significantly above solar, whereas we find
that SN hosts have predominantly subsolar or only moderately above-solar
metallicities. We also show that allowing for changes in O/Fe with the
metallicity [Fe/H] does not have a major effect on the theoretical prediction
of Timmes, Brown & Truran, so long as one is using the O/H as the independent
variable. Age may have a greater effect than metallicity -- we find that the
luminosity weighted age of the host galaxy is correlated with 56Ni yield, and
thus more massive progenitors give rise to more luminous explosions. This is
hard to understand if most SNe Ia explode when the primaries reach the
Chandrasekhar mass. Finally, we test the findings of Gallagher et al., that the
residuals of SNe Ia from the Hubble diagram are correlated with host galaxy
metallicity, and we find no such correlation.Comment: ApJ, accepted, 34 pages, 11 figures, apologies for one column format
-- necessary for the equation
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