895 research outputs found
The Economic Case for Form-Based Codes
As many communities across the US look to Form-Based Codes (FBCs) as an alternative policy tool to segregated land-use zoning, increased research seeks to understand their impact beyond the physical built environment. FBCs have received both criticism and praise by academics, lawmakers, and citizens for desired or resultant social and economic effects. However, there are limits to what FBCs can and should control as a policy tool, and as each iteration is created uniquely for a given area, the intent and principles that form the basis of that code are, potentially, more influential on the repercussions experienced than the type of code employed. As such, criticisms and praise are often wrongly ascribed to FBCs. There is little research to determine the scope of misunderstanding surrounding FBCs and the varied players involved in their implementation. Additionally, as modern FBCs are still relatively new as implemented policy governing the built environment, examples of mature development formed under their direction, or academic studies of the resultant social and economic effects of those developments, are few. This gap in knowledge allows for the continued dissemination of misleading information attributed to FBCs, both positive and negative. Using a mixed-method approach, I will perform a comparative economic analysis of mature developments formed under both conventional segregated land-use zoning and FBCs in Kendall, Florida. This analysis will aid lawmakers in making evidenced-based decisions for community economic development and will help inform planners and government officials of clarifications needed during the participatory process
Escaping Particle fluxes in the atmospheres of close-in exoplanets: I. model of hydrogen
A multi-fluid model for an atomic hydrogen-proton mixture in the upper
atmosphere of extrosolar planet is presented when the continuity and momentum
equations of each component have been already solved with an energy equation.
The particle number density, the temperature distribution and the structure of
velocity can be found by means of the model. We chose two special objects, HD
209458b and HD 189733b, as discussion samples and the conclusion is that their
mass loss rates predicted by the model are in accordance with those of
observation. The most important physical process in coupling each component is
charge exchange which tightly couples atomic hydrogen with protons. Most of the
hydrogen escaping from hot Jupiters is protons, especially in young star-planet
system. We found that the single-fluid model can describe the escape of
particles when the mass loss rate is higher than a few times g/s while
below g/s the multi-fluid model is more suitable for it due to the
decoupling of particles. We found that the predicted mass loss rates of HD
189733b with the assumption of energy-limit are a factor of 10 larger than that
calculated by our models due to the high ionization degree. For the ionized
wind which is almost compose of protons, the assumption of energy-limit is no
longer effective. We fitted the mass loss rates of the ionized wind as a
function of by calculating the variation of the mass loss rates with
UV fluxes.Comment: 35 pages, 6 figures, submitted to Ap
Conjugated Linoleic Acid Supplementation Does Not Reduce Visceral Adipose Tissue in Middle-Aged Men Engaged in a Resistance-Training Program
Conjugated linoleic acid (CLA) supplementation has shown convincing effects at reducing body fat in animals; yet human study results have been somewhat inconclusive. The purpose of this study is to determine whether four weeks of CLA supplementation, the approximate length of a commercial package, can result in a positive change in visceral adipose tissue in resistance-trained middle-aged men. Thirty overweight and moderately obese, but otherwise healthy male subjects (aged 35 to 55 years) currently involved in resistance training, were randomly assigned into CLA and placebo groups in a double-blind, placebo controlled approach. The study lasted for 12 weeks and consisted of three four-week periods. During the first four weeks (run-in period) each subject received placebo (4 g safflower oil). Throughout the next four weeks (supplementation period), the placebo group continued receiving placebo, while the CLA group received 3.2 g/d of CLA. During the final four weeks (run-out period) all subjects received the placebo. Computed tomography (CT) scans were used to measure visceral adipose tissue (VAT) at weeks 4, 8 and 12. No significant reduction in VAT cross-sectional area was determined in the CLA group during the study. On the contrary, a significant reduction in cross-sectional area of VAT of 23.12 cm2 during the supplementation period was measured in the placebo group, which was abated during the run-out period. Our results suggest that CLA supplementation of 3.2 g/d for four weeks does not promote decreases in VAT in middle-aged men currently participating in a resistance-training program
Vicarious Revolutionaries: Martial Discourse and the Origins of Mass Party Competition in the United States, 1789-1848
Evaluation of a web-based asthma self-management system: a randomised controlled pilot trial
Background
Asthma is the most common chronic condition of childhood and disproportionately affects inner-city minority children. Low rates of asthma preventer medication adherence is a major contributor to poor asthma control in these patients. Web-based methods have potential to improve patient knowledge and medication adherence by providing interactive patient education, monitoring of symptoms and medication use, and by facilitation of communication and teamwork among patients and health care providers. Few studies have evaluated web-based asthma support environments using all of these potentially beneficial interventions. The multidimensional website created for this study, BostonBreathes, was designed to intervene on multiple levels, and was evaluated in a pilot trial.
Methods
An interactive, engaging website for children with asthma was developed to promote adherence to asthma medications, provide a platform for teamwork between caregivers and patients, and to provide primary care providers with up-to-date symptom information and data on medication use. Fifty-eight (58) children primarily from inner city Boston with persistent-level asthma were randomised to either usual care or use of BostonBreathes. Subjects completed asthma education activities, and reported their symptoms and medication use. Primary care providers used a separate interface to monitor their patients’ website use, their reported symptoms and medication use, and were able to communicate online via a discussion board with their patients and with an asthma specialist.
Results
After 6-months, reported wheezing improved significantly in both intervention and control groups, and there were significant improvements in the intervention group only in night-time awakening and parental loss of sleep, but there were no significant differences between intervention and control groups in these measures. Emergency room or acute visits to a physician for asthma did not significantly change in either group. Among the subgroup of subjects with low controller medication adherence at baseline, adherence improved significantly only in the intervention group. Knowledge of the purpose of controller medicine increased significantly in the intervention group, a statistically significant improvement over the control group.
Conclusions
This pilot study suggests that a multidimensional web-based educational, monitoring, and communication platform may have positive influences on pediatric patients’ asthma-related knowledge and use of asthma preventer medications
Children's reading profiles on exiting the Reading Recovery programme: do they predict sustained progress?
© UKLA. The aim of this study was to identify reading profiles, which predict the literacy progress of Reading Recovery graduates. Reading Recovery is an intensive remediation for children after the first year of school. Children were assessed at exit from the programme and at 3-month, 6-month and 12-month follow-up points. Text Reading Level made unique contributions to word reading, spelling and writing at all time points and was consistently the best predictor of word reading. Phonological processing also made unique contributions to word reading and spelling. Reading comprehension was found to be the best predictor of National Curriculum sublevels for reading and writing, 12months later. These findings indicate that levelled texts, as employed in Reading Recovery, provide a good indication of progress in word reading, spelling and writing after the programme has been discontinued, but also present a case for assessing other reading skills (e.g., phonological processing and reading comprehension) in order to help predict sustained progress in literacy
Migration then assembly: Formation of Neptune mass planets inside 1 AU
We demonstrate that the observed distribution of `Hot Neptune'/`Super-Earth'
systems is well reproduced by a model in which planet assembly occurs in situ,
with no significant migration post-assembly. This is achieved only if the
amount of mass in rocky material is -- interior to 1
AU. Such a reservoir of material implies that significant radial migration of
solid material takes place, and that it occur before the stage of final planet
assembly.
The model not only reproduces the general distribution of mass versus period,
but also the detailed statistics of multiple planet systems in the sample.
We furthermore demonstrate that cores of this size are also likely to meet
the criterion to gravitationally capture gas from the nebula, although
accretion is rapidly limited by the opening of gaps in the gas disk. If the
mass growth is limited by this tidal truncation, then the scenario sketched
here naturally produces Neptune-mass objects with substantial components of
both rock and gas, as is observed.
The quantitative expectations of this scenario are that most planets in the
`Hot Neptune/Super-Earth' class inhabit multiple-planet systems, with
characteristic orbital spacings. The model also provides a natural division
into gas-rich (Hot Neptune) and gas-poor (Super-Earth) classes at fixed period.
The dividing mass ranges from at 10 day orbital periods to
at 100 day orbital periods. For orbital periods
days, the division is less clear because a gas atmosphere may be significantly
eroded by stellar radiation.Comment: 41 pages in preprint style, 15 figures, final version accepted to Ap
Reinterpreting the development of reading skills
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/88027/1/RRQ.40.2.3.pd
Mean Motion Resonances in Extrasolar Planetary Systems with Turbulence, Interactions, and Damping
This paper continues previous work on the effects of turbulence on mean
motion resonances in extrasolar planetary systems. Turbulence is expected to
arise in the disks that form planets, and these fluctuations act to compromise
resonant configurations. This paper extends previous work by considering how
interactions between the planets and possible damping effects imposed by the
disk affect the outcomes. These physical processes are studied using three
approaches: numerical integrations of the 3-body problem with additional
forcing due to turbulence, model equations that reduce the problem to
stochastically driven oscillators, and Fokker-Planck equations that describe
the time evolution of an ensemble of systems. With this combined approach, we
elucidate the physics of how turbulence can remove extrasolar planetary systems
from mean motion resonance. As expected, systems with sufficiently large
damping (dissipation) can maintain resonance, in spite of turbulent forcing. In
the absence of strong damping, ensembles of these systems exhibit two regimes
of behavior, where the fraction of the bound states decreases as a power-law or
as an exponential. Both types of behavior can be understood through the model
developed herein. For systems with weak interactions between planets, the model
reduces to a stochastic pendulum, and the fraction of bound states decreases as
a power-law. For highly interactive systems, the dynamics are more complicated
and the fraction of bound states decreases exponentially. We show how planetary
interactions lead to drift terms in the Fokker-Planck equation and account for
this exponential behavior. In addition to clarifying the physical processes
involved, this paper strengthens the finding that turbulence implies that mean
motions resonances should be rare.Comment: accepted to ApJ, 42 pages, 7 figure
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