129 research outputs found

    Speckle Space-Time Covariance in High-Contrast Imaging

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    We introduce a new framework for point-spread function (PSF) subtraction based on the spatio-temporal variation of speckle noise in high-contrast imaging data where the sampling timescale is faster than the speckle evolution timescale. One way that space-time covariance arises in the pupil is as atmospheric layers translate across the telescope aperture and create small, time-varying perturbations in the phase of the incoming wavefront. The propagation of this field to the focal plane preserves some of that space-time covariance. To utilize this covariance, our new approach uses a Karhunen-Lo\'eve transform on an image sequence, as opposed to a set of single reference images as in previous applications of Karhunen-Lo\'eve Image Processing (KLIP) for high-contrast imaging. With the recent development of photon-counting detectors, such as microwave kinetic inductance detectors (MKIDs), this technique now has the potential to improve contrast when used as a post-processing step. Preliminary testing on simulated data shows this technique can improve contrast by at least 10-20% from the original image, with significant potential for further improvement. For certain choices of parameters, this algorithm may provide larger contrast gains than spatial-only KLIP.Comment: Accepted to A

    Are Autistic Traits in Youth Meaningful? A Replication study in Non-referred Siblings of Youth with and without Attention-Deficit/Hyperactivity Disorder

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    Background: We previously described the high prevalence and burden of significant autistic traits (ATs) in youth with attention-deficit/hyperactivity disorder (ADHD). These traits are associated with significantly greater impairment in psychopathological, interpersonal, educational, and neuropsychological functioning. Because the sample consisted of referred ADHD youth, uncertainty remained regarding whether these findings are generalizable to non-referred populations of youths with and without ADHD. Objective: The aim of the current study was to assess the prevalence and implications of ATs in a non-referred population of siblings of probands with and without ADHD. Method: Participants were non-referred siblings of probands with ADHD (N = 257) and control probands (N = 234) of longitudinal, case-control family studies conducted at Massachusetts General Hospital. Assessments included measures of psychiatric, psychosocial, educational, and cognitive functioning. The presence of significant ATs was operationalized using the Child Behavior Checklist AT profile, which consists of combined aggregate T-scores of ≥ 195 on the Withdrawn, Social, and Thought Problems subscales. Results: ATs were significantly more prevalent among the siblings of probands with ADHD as compared with siblings of control probands (6% vs. 1%; P = .02). Siblings of probands with ADHD with a positive AT profile (N = 15) were significantly more impaired than those without an AT profile (N = 242) with regard to psychopathological, interpersonal, educational, and neuropsychological functioning. Conclusions: The current study reports a higher-than-expected prevalence of ATs in a non-referred sample of siblings of youth with ADHD, which is consistent with previous findings regarding ATs in a referred sample of youth with ADHD. The presence of ATs is associated with higher levels of morbidity and dysfunction

    Nordic Crop Wild Relative conservation : A report from two cooperation projects 2015-2019

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    The report summarizes results from a cooperation among all the Nordic countries during the period 2015 – 2019 (two projects). The work has focused on the conservation of Crop Wild Relatives (CWR), i.e. wild plant species closely related to crops. They are of special importance to humanity since traits of potential value for food security and climate change adaptation can be transferred from CWR into crops. The projects represent the first joint action on the Nordic level regarding in situ conservation of CWR. Substantial progress has been made regarding CWR conservation planning, including development of a Nordic CWR checklist and identification of suitable sites for CWR conservation. A set of recommended future actions was developed, with the most important one being initiation of active in situ conservation of CWR in all Nordic countries

    Development and validation of the Ulcerative Colitis patient-reported outcomes signs and symptoms (UC-pro/SS) diary

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    Abstract Background The clinical course of ulcerative colitis (UC) and the effects of treatment are assessed through patient-reported signs and symptoms (S&S), and endoscopic evidence of inflammation. The Ulcerative Colitis Patient-Reported Outcomes Signs and Symptoms (UC-PRO/SS) measure was developed to standardize the quantification of gastrointestinal S&S of UC in clinical trials through direct report from patient ratings. Design The UC-PRO/SS was developed by collecting data from concept elicitation (focus groups, and individual interviews), then refined through a process of cognitive interviews of 57 UC patients. Measurement properties, including item-level statistics, scaling structure, reliability, and validity, were evaluated in an observational, four-week study of adults with mild to severe UC (N = 200). Results Findings from qualitative focus groups and interviews identified nine symptom items covering bowel and abdominal symptoms. The final UC-PRO/SS daily diary includes two scales: Bowel S&S (six items) and Abdominal Symptoms (three items), each scored separately. Each scale showed evidence of adequate reliability (α = 80 and 0.66, respectively); reproducibility (intraclass correlation coefficient = 0.81, 0.71) and validity, including moderate-to-high correlations with the Partial Mayo Score (0.79; 0.45) and Inflammatory Bowel Disease Questionnaire (IBDQ) total score (− 0.70; − 0.61). Scores discriminated by level of disease severity, as defined by the Partial Mayo Score, Patient Global Rating, and Clinician Global Rating (p < 0.0001). Conclusions Results suggest that the UC-PRO/SS is a reliable and valid measure of gastrointestinal symptom severity in UC patients. Additional longitudinal data are needed to evaluate the ability of the UC-PRO/SS scores to detect responsiveness and inform the selection of responder definitions.https://deepblue.lib.umich.edu/bitstream/2027.42/143869/1/41687_2018_Article_49.pd

    Clonal spread of methicillin-resistant Staphylococcus pseudintermedius in Europe and North America: an international multicentre study

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    Objectives The aim of this study was to determine the phenotypic and genotypic resistance profiles of methicillin-resistant Staphylococcus pseudintermedius (MRSP) and to examine the clonal distribution in Europe and North America. Methods A total of 103 MRSP isolates from dogs isolated from several countries in Europe, the USA and Canada were characterized. Isolates were identified by PCR-restriction fragment length polymorphism (RFLP), antimicrobial susceptibility was determined by broth dilution or gradient diffusion, and antimicrobial resistance genes were detected using a microarray. Genetic diversity was assessed by multilocus sequence typing (MLST), PFGE and spa typing. Staphylococcal cassette chromosome mec (SCCmec) elements were characterized by multiplex PCR. Results Thirteen different sequence types (STs), 18 PFGE types and 8 spa types were detected. The hybrid SCCmec element II-III described in a MRSP isolate was present in 75 (72.8%) isolates. The remaining isolates either had SCCmec type III (n = 2), IV (n = 6), V (n = 14) or VII-241 (n = 4) or were non-typeable (n = 2). The most common genotypes were ST71(MLST)-J(PFGE)-t02(spa)-II-III(SCCmec) (56.3%) and ST68-C-t06-V (12.6%). In addition to mecA-mediated β-lactam resistance, isolates showed resistance to trimethoprim [dfr(G)] (90.3%), gentamicin/kanamycin [aac(6′)-Ie-aph(2′)-Ia] (88.3%), kanamycin [aph(3′)-III] (90.3%), streptomycin [ant(6′)-Ia] (90.3%), streptothricin (sat4) (90.3%), macrolides and/or lincosamides [erm(B), lnu(A)] (89.3%), fluoroquinolones (87.4%), tetracycline [tet(M) and/or tet(K)] (69.9%), chloramphenicol (catpC221) (57.3%) and rifampicin (1.9%). Conclusions Two major clonal MRSP lineages have disseminated in Europe (ST71-J-t02-II-III) and North America (ST68-C-t06-V). Regardless of their geographical or clonal origin, the isolates displayed resistance to the major classes of antibiotics used in veterinary medicine and thus infections caused by MRSP isolates represent a serious therapeutic challeng

    PsAID12 Provisionally Endorsed at OMERACT 2018 as Core Outcome Measure to Assess Psoriatic Arthritis-specific Health-related Quality of Life in Clinical Trials

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    OBJECTIVE: The Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) and Outcome Measures in Rheumatology (OMERACT) psoriatic arthritis (PsA) working group is developing a Core Outcome Measurement Set for PsA clinical trials [randomized controlled trials (RCT) and longitudinal observational studies (LOS)] using the OMERACT Filter 2.1 instrument selection algorithm. Our objective was to assess the Psoriatic Arthritis Impact of Disease questionnaire (PsAID12) for the measurement of the core domain PsA-specific health-related quality of life (HRQOL).METHODS: PsAID12 measurement property evidence gathered in a systematic literature review, and additional analyses conducted in LOS, were used to inform a consensus process. Analyses that had not been published were independently reviewed by the OMERACT technical advisory group. Data and process were presented, discussed in breakout groups, and voted on at the OMERACT conference (Terrigal, Australia, May 2018).RESULTS: PsAID12 fulfilled the green (good to go) OMERACT standards for domain match, feasibility, reliability, and construct/longitudinal construct validity. Discrimination and thresholds of meaning were amber (caution but good enough to go forward). The overall working group recommendation was amber/provisional endorsement of PsAID12 for measuring PsA-specific HRQOL in RCT and LOS. Of 96 participants who voted at the PsA OMERACT workshop, 87.5% (84) voted "yes" to endorse this recommendation; 14 of the 96 were patient research partners (PRP) and 93% of them (13) voted "yes"; 82 participants were not PRP and 87% of them (71) voted "yes."CONCLUSION: At OMERACT 2018, PsAID12 was the first patient-reported outcome measure provisionally endorsed as a core outcome measure for disease-specific HRQOL in PsA clinical trials. PsAID12 discrimination and improvement thresholds will be studied in future RCT.</p

    Updating the Psoriatic Arthritis (PsA) core domain set:A report from the PsA workshop at OMERACT 2016

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    OBJECTIVE: To include the patient perspective in accordance with the Outcome Measures in Rheumatology (OMERACT) Filter 2.0 in the updated Psoriatic Arthritis (PsA) Core Domain Set for randomized controlled trials (RCT) and longitudinal observational studies (LOS).METHODS: At OMERACT 2016, research conducted to update the PsA Core Domain Set was presented and discussed in breakout groups. The updated PsA Core Domain Set was voted on and endorsed by OMERACT participants.RESULTS: We conducted a systematic literature review of domains measured in PsA RCT and LOS, and identified 24 domains. We conducted 24 focus groups with 130 patients from 7 countries representing 5 continents to identify patient domains. We achieved consensus through 2 rounds of separate surveys with 50 patients and 75 physicians, and a nominal group technique meeting with 12 patients and 12 physicians. We conducted a workshop and breakout groups at OMERACT 2016 in which findings were presented and discussed. The updated PsA Core Domain Set endorsed with 90% agreement by OMERACT 2016 participants included musculoskeletal disease activity, skin disease activity, fatigue, pain, patient's global assessment, physical function, health-related quality of life, and systemic inflammation, which were recommended for all RCT and LOS. These were important, but not required in all RCT and LOS: economic cost, emotional well-being, participation, and structural damage. Independence, sleep, stiffness, and treatment burden were on the research agenda.CONCLUSION: The updated PsA Core Domain Set was endorsed at OMERACT 2016. Next steps for the PsA working group include evaluation of PsA outcome measures and development of a PsA Core Outcome Measurement Set.</p
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