203 research outputs found

    Recent Transits of the Super-Earth Exoplanet GJ 1214b

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    We report recent ground-based photometry of the transiting super-Earth exoplanet GJ1214b at several wavelengths, including the infrared near 1.25 microns (J-band). We observed a J-band transit with the FLAMINGOS infrared imager and the 2.1-meter telescope on Kitt Peak, and we observed several optical transits using a 0.5-meter telescope on Kitt Peak and the 0.36-meter Universidad de Monterrey Observatory telescope. Our high-precision J-band observations exploit the brightness of the M-dwarf host star at this infrared wavelength as compared to the optical, as well as being significantly less affected by stellar activity and limb darkening. We fit the J-band transit to obtain an independent determination of the planetary and stellar radii. Our radius for the planet (2.61^+0.30_-0.11 Earth radii) is in excellent agreement with the discovery value reported by Charbonneau et al. based on optical data. We demonstrate that the planetary radius is insensitive to degeneracies in the fitting process. We use all of our observations to improve the transit ephemeris, finding P=1.5804043 +/- 0.0000005 days, and T0=2454964.94390 +/- 0.00006 BJD.Comment: Accepted for ApJ Letters, 7 pages, 3 Figures, 2 Table

    White Light-Informed Optical Properties Improve Ultrasound-Guided Fluorescence Tomography of Photoactive Protoporphyrin IX

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    Subsurface fluorescence imaging is desirable for medical applications, including protoporphyrin-IX (PpIX)-based skin tumor diagnosis, surgical guidance, and dosimetry in photodynamic therapy. While tissue optical properties and heterogeneities make true subsurface fluorescence mapping an ill-posed problem, ultrasound-guided fluorescence-tomography (USFT) provides regional fluorescence mapping. Here USFT is implemented with spectroscopic decoupling of fluorescence signals (auto-fluorescence, PpIX, photoproducts), and white light spectroscopy-determined bulk optical properties. Segmented US images provide a priori spatial information for fluorescence reconstruction using region-based, diffuse FT. The method was tested in simulations, tissue homogeneous and inclusion phantoms, and an injected-inclusion animal model. Reconstructed fluorescence yield was linear with PpIX concentration, including the lowest concentration used, 0.025  μg/ml . White light spectroscopy informed optical properties, which improved fluorescence reconstruction accuracy compared to the use of fixed, literature-based optical properties, reduced reconstruction error and reconstructed fluorescence standard deviation by factors of 8.9 and 2.0, respectively. Recovered contrast-to-background error was 25% and 74% for inclusion phantoms without and with a 2-mm skin-like layer, respectively. Preliminary mouse-model imaging demonstrated system feasibility for subsurface fluorescence measurement in vivo. These data suggest that this implementation of USFT is capable of regional PpIX mapping in human skin tumors during photodynamic therapy, to be used in dosimetric evaluations

    Extrasolar Planet Transits Observed at Kitt Peak National Observatory

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    We obtained J-, H- and JH-band photometry of known extrasolar planet transiting systems at the 2.1-m Kitt Peak National Observatory Telescope using the FLAMINGOS infrared camera between October 2008 and October 2011. From the derived lightcurves we have extracted the mid-transit times, transit depths and transit durations for these events. The precise mid-transit times obtained help improve the orbital periods and also constrain transit-time variations of the systems. For most cases the published system parameters successfully accounted for our observed lightcurves, but in some instances we derive improved planetary radii and orbital periods. We complemented our 2.1-m infrared observations using CCD z'-band and B-band photometry (plus two Hydrogen Alpha filter observations) obtained with the Kitt Peak Visitor's Center telescope, and with four H-band transits observed in October 2007 with the NSO's 1.6-m McMath-Pierce Solar Telescope. The principal highlights of our results are: 1) our ensemble of J-band planetary radii agree with optical radii, with the best-fit relation being: (Rp/R*)J = 0.0017 + 0.979 (Rp/R*)optical, 2) We observe star spot crossings during the transit of WASP-11/HAT-P-10, 3) we detect star spot crossings by HAT-P-11b (Kepler-3b), thus confirming that the magnetic evolution of the stellar active regions can be monitored even after the Kepler mission has ended, and 4) we confirm a grazing transit for HAT-P-27/WASP-40. In total we present 57 individual transits of 32 known exoplanet systems.Comment: 33 pages, 6 figures, accepted in Publications of the Astronomical Society of the Pacifi

    Recent Transits of the Super-Earth Exoplanet GJ 1214B

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    We report recent ground-based photometry of the transiting super-Earth exoplanet GJ1214b at several wavelengths, including the infrared near 1.25 microns (J-band). We observed a J-band transit with the FLAMINGOS infrared imager and the 2.1-meter telescope on Kitt Peak, and we observed several optical transits using a 0.5-meter telescope on Kitt Peak and the 0.36-meter Universidad de Monterrey Observatory telescope. Our high-precision J-band observations exploit the brightness of the M-dwarf host star at this infrared wavelength as compared to the optical, as well as being significantly less affected by stellar activity and limb darkening. We fit the J-band transit to obtain an independent determination of the planetary and stellar radii. Our radius for the planet (2.61 +0.30 / -0.11 Earth radii) is in excellent agreement with the discovery value reported by Charbonneau et al. based on optical data. We demonstrate that the planetary radius is insensitive to degeneracies in the fitting process. We use all of our observations to improve the transit ephemeris, finding P=1.5804043 +/- 0.0000005 days, and T0=2454964.94390 +/- 0.00006 BJD

    A new outcome measure for LUTS: Symptoms of Lower Urinary Tract Dysfunction Research Network Symptom Index‐29 (LURN SI‐29) questionnaire

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    AimsTo develop a representative, self‐report assessment of lower urinary tract symptoms (LUTS) for men and women, the symptoms of Lower Urinary Tract Dysfunction Research Network Symptom Index‐29 (LURN SI‐29).MethodsWomen and men seeking treatment for LUTS at one of six academic medical centers in the US were assessed at baseline, 3‐month and 12‐month intervals. Twelve‐month data on 78 LURN SI‐29 items were analyzed among 353 women and 420 men using exploratory factor analysis (EFA), with factor structure confirmed using confirmatory factor analysis (CFA). Internal consistency, reliability, and validity of the five developed scales were evaluated by assessing correlations with the American Urological Association Symptom Index (AUA‐SI), the genitourinary pain index (GUPI), and the Pelvic Floor Distress Inventory‐20 (PFDI‐20), and by examining expected sex differences in scores.ResultsEFA results (n = 150 women; 150 men) produced an interpretable eight‐factor solution, with three of the factors comprised of dichotomous items addressing LUTS‐associated sensations. The remaining five factors, confirmed with CFA in an independent sample of 473 participants, produced five scales: incontinence, urgency, voiding difficulty, bladder pain, and nocturia. Subscales and total LURN SI‐29 scores were correlated as expected with AUA‐SI, GUPI, and PFDI‐20. LURN SI‐29 scores also performed as expected in differentiating men from women based upon clinically expected differences, with men reporting more voiding difficulties and nocturia, and women reporting more urgency and incontinence.ConclusionsThe LURN SI‐29 questionnaire has the potential to improve research and clinical outcome measurement for both men and women with LUTS.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/150585/1/nau24067.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150585/2/nau24067_am.pd

    Antiretroviral Adherence Following Prison Release in a Randomized Trial of the imPACT Intervention to Maintain Suppression of HIV Viremia

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    Many people living with HIV (PLWH) pass through correctional facilities each year, a large proportion of whom do not maintain viral suppression following release. We examined the effects of imPACT, an intervention designed to promote post-release viral suppression, on antiretroviral therapy (ART) adherence. PLWH awaiting release from prisons in two southern states were randomized to imPACT (consisting of motivational interviewing, care linkage coordination, and text message medication reminders) versus standard care (SC). ART adherence, measured by unannounced monthly telephone pill counts, was compared between study arms over 6 months post-release. Of 381 participants eligible for post-release follow-up, 302 (79%) completed ≥ 1 of 6 possible pill counts (median: 4; IQR 1–6). Average adherence over follow-up was 80.3% (95% CI 77.5, 83.1) and 81.0% (78.3, 83.6) of expected doses taken in the imPACT and SC arms, respectively. There was no difference between arms when accounting for missing data using multiple imputation (mean difference = − 0.2 percentage points [− 3.7, 3.3]), controlling for study site and week of follow-up. Of the 936 (40.9%) pill counts that were missed, 212 (22.7%) were due to re-incarceration. Those who missed pill counts for any reason were more likely to be unsuppressed, suggesting that they had lower adherence. However, missingness was balanced between arms. Among PLWH released from prison, ART adherence averaged > 80% in both study arms over 6 months—a level higher than seen with most other chronic diseases. However, missing data may have led to an overestimate of adherence. Factors independent of the intervention influence ART adherence in this population and should be identified to inform future targeted interventions

    Principles and criteria in the development and optimization of topical therapeutic products : Sponsored by the American Association of Pharmaceutical Scientists (AAPS) and U.S. Food and Drug Administration (FDA)

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    This report derived from the dermatological workshop discusses the problems and issues in the development and optimization of topical therapeutic drug products. It provides a clear understanding and differentiation between transdermal and dermal products. The report also discusses the bioavailability/bioequivalence issues for topical therapeutic products.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30099/1/0000471.pd

    A13K-0336: Airborne Multi-Wavelength High Spectral Resolution Lidar for Process Studies and Assessment of Future Satellite Remote Sensing Concepts

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    NASA Langley recently developed the world's first airborne multi-wavelength high spectral resolution lidar (HSRL). This lidar employs the HSRL technique at 355 and 532 nm to make independent, unambiguous retrievals of aerosol extinction and backscatter. It also employs the standard backscatter technique at 1064 nm and is polarization-sensitive at all three wavelengths. This instrument, dubbed HSRL-2 (the secondgeneration HSRL developed by NASA Langley), is a prototype for the lidar on NASA's planned Aerosols- Clouds-Ecosystems (ACE) mission. HSRL-2 completed its first science mission in July 2012, the Two-Column Aerosol Project (TCAP) conducted by the Department of Energy (DOE) in Hyannis, MA. TCAP presents an excellent opportunity to assess some of the remote sensing concepts planned for ACE: HSRL-2 was deployed on the Langley King Air aircraft with another ACE-relevant instrument, the NASA GISS Research Scanning Polarimeter (RSP), and flights were closely coordinated with the DOE's Gulfstream-1 aircraft, which deployed a variety of in situ aerosol and trace gas instruments and the new Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR). The DOE also deployed their Atmospheric Radiation Measurement Mobile Facility and their Mobile Aerosol Observing System at a ground site located on the northeastern coast of Cape Cod for this mission. In this presentation we focus on the capabilities, data products, and applications of the new HSRL-2 instrument. Data products include aerosol extinction, backscatter, depolarization, and optical depth; aerosol type identification; mixed layer depth; and rangeresolved aerosol microphysical parameters (e.g., effective radius, index of refraction, single scatter albedo, and concentration). Applications include radiative closure studies, studies of aerosol direct and indirect effects, investigations of aerosol-cloud interactions, assessment of chemical transport models, air quality studies, present (e.g., CALIPSO) and future (e.g., EarthCARE) satellite calibration/validation, and development/assessment of advanced retrieval techniques for future satellite applications (e.g., lidar+polarimeter retrievals of aerosol and cloud properties). We will also discuss the relevance of HSRL-2 measurement capabilities to the ACE remote sensing concept
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