10,457 research outputs found
The Pauli Exclusion Principle and SU(2) vs. SO(3) in Loop Quantum Gravity
Recent attempts to resolve the ambiguity in the loop quantum gravity
description of the quantization of area has led to the idea that j=1 edges of
spin-networks dominate in their contribution to black hole areas as opposed to
j=1/2 which would naively be expected. This suggests that the true gauge group
involved might be SO(3) rather than SU(2) with attendant difficulties. We argue
that the assumption that a version of the Pauli principle is present in loop
quantum gravity allows one to maintain SU(2) as the gauge group while still
naturally achieving the desired suppression of spin-1/2 punctures. Areas come
from j=1 punctures rather than j=1/2 punctures for much the same reason that
photons lead to macroscopic classically observable fields while electrons do
not.Comment: This paper received an "honorable mention" in the 2003 Essay
Competition of the Gravity Research Foundation and should be appearing in a
special issue of Int. J. Mod. Phys.
Ground-based NIR emission spectroscopy of HD189733b
We investigate the K and L band dayside emission of the hot-Jupiter HD
189733b with three nights of secondary eclipse data obtained with the SpeX
instrument on the NASA IRTF. The observations for each of these three nights
use equivalent instrument settings and the data from one of the nights has
previously reported by Swain et al (2010). We describe an improved data
analysis method that, in conjunction with the multi-night data set, allows
increased spectral resolution (R~175) leading to high-confidence identification
of spectral features. We confirm the previously reported strong emission at
~3.3 microns and, by assuming a 5% vibrational temperature excess for methane,
we show that non-LTE emission from the methane nu3 branch is a physically
plausible source of this emission. We consider two possible energy sources that
could power non-LTE emission and additional modelling is needed to obtain a
detailed understanding of the physics of the emission mechanism. The validity
of the data analysis method and the presence of strong 3.3 microns emission is
independently confirmed by simultaneous, long-slit, L band spectroscopy of HD
189733b and a comparison star.Comment: ApJ accepte
Using Formative Research and Audience-Centric Intelligence to Develop the #JustBe Digital Magazine: An mHealth Strategy to Improve Adolescent Sexual Health
Digital strategies may help to overcome challenges in providing contraception education to overlooked and key sub-populations (older teens, ethnic minority youth, LGBTQ youth, high school dropouts and males). However, many current digital strategies are not culturally specific and often have limited information on the most effective contraceptive methods. In this article, we describe the preliminary steps used to develop #JustBe, a user-centered digital strategy for ethnic minority older youth and young adults with a specific focus contraception, sexual health, consent, and healthy relationships. Technology-based strategies such as #JustBe offer advantages over traditional face-to-face methods by utilizing a confidential way to retrieve sexual health information that may be sensitive and potentially embarrassing. Questions still remain regarding the feasibility and long-term effects of mobile health interventions for contraception use
Working With Faith-Based Communities to Develop an Education Tool kit on Relationships, Sexuality, and Contraception
Communities disproportionately affected from higher rates of unplanned teen births are in need of sustainable approaches to prevention strategies. One approach is to build the capacity of faith-based communities (FBCs) to address the sexual health needs of the surrounding community. However there is a need for comprehensive, user-friendly resources designed for FBCs that provide critical decision-making information related to pregnancy prevention inclusive of contraception. Using community-based, theoretical and practice-informed strategies, we developed a user-friendly sexuality education tool kit in five phases: (1) building relationships with faith leaders; (2) piloting educational sessions within churches; (3) gaining insight from participating faith leaders; (4) creating the tool kit; and (5) collecting feedback from training and implementation. Our findings suggest faith leaders remained motivated to overcome perceived barriers by their mission to serve their communities. A sexuality education tool kit that is respectful and guided by the input of FBCs can be a viable and innovative approach to address teen pregnancy
Primary and secondary eclipse spectroscopy with JWST: exploring the exoplanet parameter space
Eclipse exoplanet spectroscopy has yielded detection of H_2O, CH_4, CO_2 and
CO in the atmosphere of hot jupiters and neptunes. About 40 large terrestrial
planets are announced or confirmed, two of which are transiting, and another
deemed habitable. Hence the potential for eclipse spectroscopy of terrestrial
planets with James Webb Space Telescope (JWST) has become an active field of
study. We explore the parameter space (type of stars, planet orbital periods
and types, and instruments/wavelengths) in terms of the signal-to-noise ratio
(S/N) achievable on the detection of spectroscopic features. We use analytic
formula and model data for both the astrophysical scene and the instrument, to
plot S/N contour maps, while indicating how the S/N scales with the fixed
parameters. We systematically compare stellar photon noise-only figures with
ones including detailed instrumental and zodiacal noises. Likelihood of
occurring targets is based both on model and catalog star population of the
solar neighborhood. The 9.6 micron ozone band is detectable (S/N = 3) with
JWST, for a warm super-earth 6.7 pc away, using ~2% of the 5-year nominal
mission time (summing observations, M4V and lighter host star for primary
eclipses, M5V for secondary). If every star up to this mass limit and distance
were to host a habitable planet, there should be statistically ~1 eclipsing
case. Investigation of systematic noises in the co-addition of 5 years worth-,
tens of days separated-, hours-long observations is critical, complemented by
dedicated characterisation of the instruments, currently in integration phase.
The census of nearby transiting habitable planets must be complete before the
beginning of science operations.Comment: Accepted for publication in A&A, 16 pages, 19 figure
A feasibility study to evaluate a purposeful walk intervention with a distance goal using a commercially available activity monitor in elderly people post total hip replacement surgery
INTRODUCTION: Total hip replacement (THR) is performed in an increasing number of individuals around the world and while improvements in pain reduction and long-term enhancement of muscle strength are well documented, the improvement in daily activity does not follow the same trend. This study aimed to determine the feasibility of a 5-week intervention where a personalised outdoor walking distance is monitored using a commercial activity monitor (Fitbit Charge 4). METHOD: Data was collected on gait and activities of daily living using patient reported outcome measures. Following the completion of the intervention period, participants took part in a semi-structured interview to voice their opinion on the use of the activity monitor, their experiences, and any challenges in order to assess the feasibility of the intervention. All quantitative data were presented descriptively, using appropriate summary statistics. Interviews were analysed using thematic analysis. RESULTS: Five participants who had undergone total hip replacement surgery within the postoperative period of 3 to 6Â months were recruited from the local community. CONCLUSION: The findings suggest that the intervention was feasible and that it encouraged all participants to increase their daily activity. Therefore, it can be concluded that a follow-up effectiveness trial is warranted
Use of Heart Rate Reserve and Rating of Perceived Exertion to Prescribe Exercise Intensity in Diabetic Autonomic Neueropathy
Objective- Individuals with diabetic autonomic neuropathy (DAN) exhibit an increased resting heart rate but depressed maximal heart rate. Thus, the purpose of this study was to examine the validity of using either percent of heart rate reserve (HRR) or a rating of perceived exertion (RPE) scale to prescribe exercise intensity in diabetic individuals both with and without DAN. Research Design and Methods-The subjects consisted of 23 individuals with type 2 diabetes, ages 45-75 years, with (DAN; n=13) or without (No DAN; n=10) clinical signs of DAN, as assessed by heart rate variability using the expiration-to-inspiration ratio of the R-R interval. Peak aerobic capacity was determined using a graded protocol on a cycle ergometer, with RPE, heart rate, and Vo2 values recorded at each Stage. Results-The subjects were similar with the exception of depressed autonomic function in DAN subjects. Peak respiratory exchange ratio values were significantly higher (P\u3c0.05) in the DAN group (1.08 +/- 0.02 vs. 1.02 +/- 0.01 in No DAN subjects), although DAN subjects exhibited a significantly lower (P\u3c0.05) peak exercise heart rate. A similarly highly linear relationship between %HRR and percent Vo2 reserve (Vo2R) existed for both groups (r=0.98). A similar slightly weaker relationship (r=0.94) was found between RPE and %Vo2R. Conclusions-in conclusion, in diabetic individuals, %HRR provides an accurate prediction of %VO2R and can be used to prescribe and monitor exercise intensity, regardless of the presence of DAN. The RPE scale is, also a valid, albeit slightly less accurate, method to monitor exercise intensity in diabetic individuals
Why Do People Undergo THR and What Do They Expect to GainâA Comparison of the Views of Patients and Health Care Professionals
Little concerted effort has been made to understand why individuals undergo total hip replacement (THR) surgery and their rehabilitation goals. Similarly, insight of views and perspective of health care professionalsâ (HCPs) regarding surgery and what objective measures help them with decision-making is lacking. This patient and public involvement report aimed to explore both patientsâ and HCPsâ perspectives of THR surgery. Twenty patients, 10 pre-THR, 10 post-THR, 9 physiotherapists, and 6 surgeons took part. Results suggest a consensus among patients and HCPs on pain reduction being the main reason for undergoing THR. The inability to carry out simple daily activities such as dog walking and sleep deprivation had a significant effect on patientsâ mental and physical well-being. This article is the first to explore the views of THR patients and HCPs on reasons behind THR surgery amalgamated into a single report. As walking is important, wearable activity monitors are suggested as a possible motivator to enhance patient compliance to self-care rehabilitation and increase quality of life. A future research project on the use of such wearable activity monitors in enhancing mobility post-THR is therefore planned
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