1,238 research outputs found
Complex Spiral Structure in the HD 100546 Transitional Disk as Revealed by GPI and MagAO
We present optical and near-infrared high-contrast images of the transitional disk HD 100546 taken with the Magellan Adaptive Optics system (MagAO) and the Gemini Planet Imager (GPI). GPI data include both polarized intensity and total intensity imagery, and MagAO data are taken in Simultaneous Differential Imaging mode at Hα. The new GPI H-band total intensity data represent a significant enhancement in sensitivity and field rotation compared to previous data sets and enable a detailed exploration of substructure in the disk. The data are processed with a variety of differential imaging techniques (polarized, angular, reference, and simultaneous differential imaging) in an attempt to identify the disk structures that are most consistent across wavelengths, processing techniques, and algorithmic parameters. The inner disk cavity at 15 au is clearly resolved in multiple data sets, as are a variety of spiral features. While the cavity and spiral structures are identified at levels significantly distinct from the neighboring regions of the disk under several algorithms and with a range of algorithmic parameters, emission at the location of HD 100546 "c" varies from point-like under aggressive algorithmic parameters to a smooth continuous structure with conservative parameters, and is consistent with disk emission. Features identified in the HD 100546 disk bear qualitative similarity to computational models of a moderately inclined two-armed spiral disk, where projection effects and wrapping of the spiral arms around the star result in a number of truncated spiral features in forward-modeled images
Improved Test Planning and Analysis Through the Use of Advanced Statistical Methods
The goal of this work is, through computational simulations, to provide statistically-based evidence to convince the testing community that a distributed testing approach is superior to a clustered testing approach for most situations. For clustered testing, numerous, repeated test points are acquired at a limited number of test conditions. For distributed testing, only one or a few test points are requested at many different conditions. The statistical techniques of Analysis of Variance (ANOVA), Design of Experiments (DOE) and Response Surface Methods (RSM) are applied to enable distributed test planning, data analysis and test augmentation. The D-Optimal class of DOE is used to plan an optimally efficient single- and multi-factor test. The resulting simulated test data are analyzed via ANOVA and a parametric model is constructed using RSM. Finally, ANOVA can be used to plan a second round of testing to augment the existing data set with new data points. The use of these techniques is demonstrated through several illustrative examples. To date, many thousands of comparisons have been performed and the results strongly support the conclusion that the distributed testing approach outperforms the clustered testing approach
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Psychosocial burden and healthcare disillusionment in recurrent UTI: a large-scale international survey of patient perspectives
ObjectivesRecurrent UTI (rUTI) is a debilitating health condition that is associated with persistent mental, physical, and social burdens. People living with rUTI face inconsistencies in diagnostic testing and fragmented treatment pathways alongside their symptoms, which are likely to add considerably to their illness-related burdens. This study aimed to characterize the factors negatively impacting this population using the qualitative perspectives of people living with the condition.MethodsQualitative data were collected via free-text responses using an online survey hosted by an rUTI patient advocacy website. Female participants with self-reported rUTI (n = 1,983) described the factors that were most salient to their experience of living with the condition. Data were analyzed using a coding reliability approach to thematic analysis.ResultsTwo overarching themes were identified: (1) the patient burden of rUTI, which describes the multifaceted biopsychosocial impact of the illness, and (2) healthcare disillusionment, which describes patient dissatisfaction with healthcare received, both in terms of the treatments offered and communication with healthcare professionals. The patient burden of rUTI encompassed four subordinate themes: facing ongoing uncertainty; symptom salience; sex is not simple anymore; and perceived UTI stigma. Healthcare disillusionment included three subordinate themes: discomfort with frequent antibiotic use; fragmented treatment pathways; and devalued patient perspectives.ConclusionsThe findings demonstrated that ambiguity in the diagnosis of rUTI and inconsistencies in the subsequent treatment pathway are exacerbated by poor patientâclinician communication. The extent of the female-specific burden of rUTI symptoms confirmed the harmful effects of illness-related stigma. This novel qualitative reporting of rUTI symptom burden and life impact highlights the urgent need for increased patient-centered care for those living with rUTI. More effective rUTI management could have a major impact on treatment outcomes and patient-reported psychosocial wellbeing
Speech and communication in Parkinsonâs disease: a cross-sectional exploratory study in the UK
Objective: To assess associations between cognitive status, intelligibility, acoustics and functional communication in PD. Design: Cross-sectional exploratory study of functional communication, including a within-participants experimental design for listener assessment. Setting: A major academic medical centre in the East of England, UK. Participants: Questionnaire data were assessed for 45 people with Parkinsonâs disease (PD), who had self-reported speech or communication difficulties and did not have clinical dementia. Acoustic and listener analyses were conducted on read and conversational speech for 20 people with PD and 20 familiar conversation partner controls without speech, language or cognitive difficulties. Main outcome measures: Functional communication assessed by the Communicative Participation Item Bank (CPIB) and Communicative Effectiveness Survey (CES). Results: People with PD had lower intelligibility than controls for both the read (mean difference 13.7%, p=0.009) and conversational (mean difference 16.2%, p=0.04) sentences. Intensity and pause were statistically significant predictors of intelligibility in read sentences. Listeners were less accurate identifying the intended emotion in the speech of people with PD (14.8% point difference across conditions, p=0.02) and this was associated with worse speaker cognitive status (16.7% point difference, p=0.04). Cognitive status was a significant predictor of functional communication using CPIB (F=8.99, p=0.005, η2 = 0.15) but not CES. Intelligibility in conversation sentences was a statistically significant predictor of CPIB (F=4.96, p=0.04, η2 = 0.19) and CES (F=13.65, p=0.002, η2 = 0.43). Read sentence intelligibility was not a significant predictor of either outcome. Conclusions: Cognitive status was an important predictor of functional communicationâthe role of intelligibility was modest and limited to conversational and not read speech. Our results highlight the importance of focusing on functional communication as well as physical speech impairment in speech and language therapy (SLT) for PD. Our results could inform future trials of SLT techniques for PD
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Confirmatory structural validation and refinement of the Recurrent Urinary Tract Infection Symptom Scale
AbstractObjectivesTo confirm the structural validity of the Recurrent Urinary Tract Infection Symptom Scale (RUTISS), determining whether a bifactor model appropriately fits the questionnaire's structure and identifying areas for refinement. Used in conjunction with established clinical testing methods, this patientâreported outcome measure addresses the urgent need to validate the patient perspective.Patients and methodsA clinically and demographically diverse sample of 389 people experiencing recurrent UTI across 37 countries (96.9% female biological sex, aged 18â87 years) completed the RUTISS online. A bifactor graded response model was fitted to the data, identifying potential items for deletion if they indicated significant differential item functioning (DIF) based on sociodemographic characteristics, contributed to local item dependence or demonstrated poor fit or discrimination capability.ResultsThe final RUTISS comprised a 3âitem symptom frequency section, a 1âitem global rating of change scale and an 11âitem general ârUTI symptom and pain severityâ subscale with four subâfactor domains measuring âurinary symptomsâ, âurinary presentationâ, âUTI pain and discomfortâ and âbodily sensationsâ. The bifactor model fit indices were excellent (root mean square error of approximation [RMSEA] = 0.041, comparative fit index [CFI] = 0.995, standardised root mean square residual [SRMSR] = 0.047), and the meanâsquare fit statistics indicated that all items were productive for measurement (mean square fit indices [MNSQ] = 0.64 â 1.29). Eightyâone per cent of the common model variance was accounted for by the general factor and subâfactors collectively, and all factor loadings were greater than 0.30 and communalities greater than 0.60. Items indicated high discrimination capability (slope parameters > 1.35).ConclusionThe 15âitem RUTISS is a patientâgenerated, psychometrically robust questionnaire that dynamically assesses the patient experience of recurrent UTI symptoms and pain. This brief tool offers the unique opportunity to enhance patientâcentred care by supporting shared decisionâmaking and patient monitoring
Adipose Tissue Inflammation in Diabetic versus Non-diabetic Pregnancies
Objective: Beyond weight associated with fetus, placenta, amniotic fluid and increased blood volume, adipose tissue (AT) expansion is an accepted and expected component of pregnancy weight gain. Normal pregnancy is associated with relative insulin resistance (IR). In non-pregnant humans, AT expansion has been associated with IR and AT inflammation. However, it is not known whether AT expansion and IR in pregnancy are also associated with AT inflammation. This pilot study examined relationships between AT expansion and inflammation in control versus diabetic pregnancies.
Methods: Eligible subjects undergoing scheduled Cesarean delivery for obstetric indications were prospectively enrolled. Subjects provided demographic and anthropometric data, and biologic specimens. Immunofluorescence microscopy was performed on subcutaneous (SQ) and omental (OM) AT samples to evaluate macrophage infiltration. Included gravidas had paired AT samples and either negative glucola screening (controls) or gestational or pre-gestational Type 2 diabetes mellitus (T2DM).
Results: 13 subjects with SQ and OM AT samples were evaluated (10-controls, 3-diabetics (2-T2DM and 1-GDM)). Mean BMI and gestational weight gain of controls was 27.8 kg/m2 (range 19.5-42) and 27.6 pounds (range 15-36) and of diabetics was 30.6 kg/m2 (range 30-33) and 19 pounds (range -3-30), respectively. Macrophage infiltration was seen in OM AT from 2/ 3 diabetics and 0/ 10 controls (see figure).
Conclusions: These results indicate that AT expansion in non-diabetic pregnancies is not accompanied by macrophage infiltration. Thus, the IR of normal pregnancy is unlikely to be related to AT inflammation, and AT expansion per se does not lead to AT inflammation. However, as has been reported for T2DM in non-pregnant humans, the presence (T2DM) or development (GDM) of diabetes in pregnancy is associated with macrophage infiltration of AT. Despite the small sample size, the observed large differences in macrophage infiltration between controls and diabetics suggest that these findings will persist in a larger cohort
Dynamical Mass Measurement of the Young Spectroscopic Binary V343 Normae AaAb Resolved With the Gemini Planet Imager
We present new spatially resolved astrometry and photometry from the Gemini
Planet Imager of the inner binary of the young multiple star system V343
Normae, which is a member of the beta Pictoris moving group. V343 Normae
comprises a K0 and mid-M star in a ~4.5 year orbit (AaAb) and a wide 10" M5
companion (B). By combining these data with archival astrometry and radial
velocities we fit the orbit and measure individual masses for both components
of M_Aa = 1.10 +/- 0.10 M_sun and M_Ab = 0.290 +/- 0.018 M_sun. Comparing to
theoretical isochrones, we find good agreement for the measured masses and JHK
band magnitudes of the two components consistent with the age of the beta Pic
moving group. We derive a model-dependent age for the beta Pic moving group of
26 +/- 3 Myr by combining our results for V343 Normae with literature
measurements for GJ 3305, which is another group member with resolved binary
components and dynamical masses.Comment: 12 pages, 7 figures. Accepted to A
Improving and Assessing Planet Sensitivity of the GPI Exoplanet Survey with a Forward Model Matched Filter
We present a new matched filter algorithm for direct detection of point
sources in the immediate vicinity of bright stars. The stellar Point Spread
Function (PSF) is first subtracted using a Karhunen-Lo\'eve Image Processing
(KLIP) algorithm with Angular and Spectral Differential Imaging (ADI and SDI).
The KLIP-induced distortion of the astrophysical signal is included in the
matched filter template by computing a forward model of the PSF at every
position in the image. To optimize the performance of the algorithm, we conduct
extensive planet injection and recovery tests and tune the exoplanet spectra
template and KLIP reduction aggressiveness to maximize the Signal-to-Noise
Ratio (SNR) of the recovered planets. We show that only two spectral templates
are necessary to recover any young Jovian exoplanets with minimal SNR loss. We
also developed a complete pipeline for the automated detection of point source
candidates, the calculation of Receiver Operating Characteristics (ROC), false
positives based contrast curves, and completeness contours. We process in a
uniform manner more than 330 datasets from the Gemini Planet Imager Exoplanet
Survey (GPIES) and assess GPI typical sensitivity as a function of the star and
the hypothetical companion spectral type. This work allows for the first time a
comparison of different detection algorithms at a survey scale accounting for
both planet completeness and false positive rate. We show that the new forward
model matched filter allows the detection of fainter objects than a
conventional cross-correlation technique with a Gaussian PSF template for the
same false positive rate.Comment: ApJ accepte
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