We report the discovery of 76 new T dwarfs from the UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS). Near-infrared broad- and narrow-band photometry and spectroscopy are presented for ...the new objects, along with Wide-field Infrared Survey Explorer (WISE) and warm-Spitzer photometry. Proper motions for 128 UKIDSS T dwarfs are presented from a new two epoch LAS proper motion catalogue. We use these motions to identify two new benchmark systems: LHS 6176AB, a T8p+M4 pair and HD 118865AB, a T5.5+F8 pair. Using age constraints from the primaries and evolutionary models to constrain the radii, we have estimated their physical properties from their bolometric luminosity. We compare the colours and properties of known benchmark T dwarfs to the latest model atmospheres and draw two principal conclusions. First, it appears that the H − 4.5 and J − W2 colours are more sensitive to metallicity than has previously been recognized, such that differences in metallicity may dominate over differences in T
eff when considering relative properties of cool objects using these colours. Secondly, the previously noted apparent dominance of young objects in the late-T dwarf sample is no longer apparent when using the new model grids and the expanded sample of late-T dwarfs and benchmarks. This is supported by the apparently similar distribution of late-T dwarfs and earlier type T dwarfs on reduced proper motion diagrams that we present. Finally, we present updated space densities for the late-T dwarfs, and compare our values to simulation predictions and those from WISE.
Opsoclonus-ataxia, also called "dancing eye syndrome," is a serious neurologic condition that is often a paraneoplastic manifestation of occult neuroblastoma in early childhood. Despite resection of ...tumor and immunosuppressive therapy, outcome generally includes significant developmental and behavioral sequelae. There is controversy about how treatment alters outcome. The goals of this study were to understand the ongoing neurologic and developmental deficits of children who are treated for opsoclonus-ataxia with associated neuroblastoma; to relate treatment history to outcome; and to quantify objectively the acute changes in motor function, speech, mood, and behavior related to intravenous immunoglobulin (IVIg) treatment.
Patients were children with opsoclonus-ataxia caused by neuroblastoma, regardless of interval since diagnosis. Records were reviewed, and children underwent comprehensive evaluations, including neurologic examination and tests of cognitive and adaptive function, speech and language, and fine and gross motor abilities. Psychiatric interview and questionnaires were used to assess current and previous behavior. In 6 children, a videotaped standardized examination of eye movements was performed. Additional examinations were performed immediately before and 2 to 3 days after treatment with IVIg in 5 children.
Seventeen children, ages 1.75 to 12.62 years, were examined. All had a stage I or II neuroblastoma resected 3 months to 11 years previously. None received any other treatment for the tumor. All but 1 had received at least 1 year of either oral corticosteroids or corticotropin (ACTH); 12 had received 1 or more courses of IVIg, 2 g/kg. Three had received other immunosuppressive treatment, including cyclophosphamide. Cognitive development and adaptive behavior were delayed or abnormal in nearly all children. Expressive language was more impaired than receptive language. Speech was impaired, including both intelligibility and overall output. Fine and gross motor abilities were impaired. Increased age was strikingly associated with lower scores in all areas. Behavioral problems early in the course included severe irritability and inconsolability in all; later, oppositional behavior and sleep disorders were reported. Opsoclonus abated in all, but abnormalities in pursuit eye movements were found in all 6 children cooperative with standardized examination. Outcome did not differ in children who were treated with ACTH versus oral steroids. Three children who had received cyclophosphamide fared poorly. Immediate versus delayed treatment was not associated with better outcome. IVIg improved both gross and fine motor and speech function acutely, but we could not confirm long-term benefit of IVIg. Total number of courses of IVIg was not associated with outcome.
Opsoclonus-ataxia caused by neuroblastoma causes substantial developmental sequelae that are not adequately prevented by current treatment. The increased deficits in older children raise concern that this represents a progressive encephalopathy rather than a time-limited single insult. Although the study is cross-sectional and neither randomized nor blinded, we were unable to confirm a purported advantage of either ACTH over corticosteroids or of cyclophosphamide. A randomized study is needed but is difficult for this rare condition.
We previously reported on children with opsoclonus-ataxia and found pervasive neurodevelopmental deficits, years after onset, without a clear relationship to treatment modality or timing of ...treatment. A significant negative correlation of functional status with age at testing raised a question of whether opsoclonus-ataxia is a progressive encephalopathy. We attempted to answer this question with serial testing. In addition, we examined the relationship between clinical course and developmental outcome.
Thirteen of 17 children with opsoclonus-ataxia, all with neuroblastoma, who were previously reported were reevaluated a second time 2 to 4 years after the initial assessment. One subject who lived out of state was partially reevaluated and is included. Five new subjects (2 with neuroblastoma and 3 without) were also enrolled. Each was evaluated twice at a minimum interval of 1 year between sessions. Intercurrent medical course was recorded, emphasizing medication and relapse history. Cognitive, adaptive behavior, academic, speech and language, and motor abilities were assessed.
For the group as a whole, overall standardized, age-adjusted cognitive scores improved. Generally, younger subjects' cognitive and adaptive behavior scores improved more than older subjects. Although all subjects had gains in speech, language, and motor function, some progressed at a slow pace, and in some instances, standard scores dropped. There was a striking influence of clinical course. Although initial presentation was severe and all subjects required high doses of corticosteroids or corticotropin, 5 had a monophasic course and were able to be weaned from treatment without relapses. Fourteen had multiple relapses over the years, generally with reduction of medication or intercurrent illnesses. Of the 5 children with monophasic course, 4 are currently functioning in the average range with a full-scale IQ of > or =90 and age-appropriate academic and adaptive skills.
The results continue to raise concern that opsoclonus-ataxia is sometimes a progressive encephalopathy. A minority of children with opsoclonus-ataxia have a monophasic course. Despite initial severity of symptoms, these children may have a more benign prognosis. For the majority of children with opsoclonus-ataxia, the course includes multiple relapses and requires prolonged treatment. Developmental sequelae are significant in these children with chronic course.
This article reviews the efforts of HBO & Company in the production of a first phase clinical alerting system based on the Arden Syntax. The alerting system was integrated with a clinical data ...repository and clinical workstation to process returning laboratory results. Investigations with expert systems resulted in a C language alerting system. GUI prototyping of an authoring environment led to a Smalltalk language authoring system. Future development is expected to broaden the system scope and address the evolution of the Arden Syntax.
Outcomes research, measurement, and management have become hot topics well beyond the realm of the academic medical research community that first popularized the concept. While the ultimate outcomes ...information system will be some time in coming, it is nevertheless possible to foresee the day when patients, providers, and payers can finally answer the questions, What are our health care options? What are results of those practices? and how can we do better.
In addition to providing value today, information systems should pave the way for greater systems' value tomorrow. An organization that begins now to transform its administrative decision support ...system into a clinically oriented decision support system has taken one significant step in the direction of the future.
We report the discovery of 76 new T dwarfs from the UKIDSS Large Area Survey (LAS). Near-infrared broad and narrow-band photometry and spectroscopy are presented for the new objects, along with WISE ...and warm-Spitzer photometry. Proper motions for 128 UKIDSS T dwarfs are presented from a new two epoch LAS proper motion catalogue. We use these motions to identify two new benchmark systems: LHS 6176AB, a T8+M4 pair and HD118865AB, a T5.5+F8 pair. Using age constraints from the primaries and evolutionary models to constrain the radii we have estimated their physical properties from their bolometric luminosity. We compare the colours and properties of known benchmark T dwarfs to the latest model atmospheres and draw two principal conclusions. Firstly, it appears that the H - 4.5 and J - W2 colours are more sensitive to metallicity than has previously been recognised, such that differences in metallicity may dominate over differences in Teff when considering relative properties of cool objects using these colours. Secondly, the previously noted apparent dominance of young objects in the late-T dwarf sample is no longer apparent when using the new model grids and the expanded sample of late-T dwarfs and benchmarks. This is supported by the apparently similar distribution of late-T dwarfs and earlier-type T dwarfs on reduced proper motion diagrams that we present. Finally, we present updated space densities for the late-T dwarfs, and compare our values to simulation predictions and those from WISE.
We present 197 planet candidates discovered using data from the first year of the NASA K2 mission (Campaigns 0-4), along with the results of an intensive program of photometric analyses, stellar ...spectroscopy, high-resolution imaging, and statistical validation. We distill these candidates into sets of 104 validated planets (57 in multi-planet systems), 30 false positives, and 63 remaining candidates. Our validated systems span a range of properties, with median values of R P = 2.3 {R}\oplus , P = 8.6 days, {T}{eff} = 5300 K, and Kp = 12.7 mag. Stellar spectroscopy provides precise stellar and planetary parameters for most of these systems. We show that K2 has increased by 30% the number of small planets known to orbit moderately bright stars (1-4 R ⊕, Kp = 9-13 mag). Of particular interest are 76 planets smaller than 2 R ⊕, 15 orbiting stars brighter than Kp = 11.5 mag, 5 receiving Earth-like irradiation levels, and several multi-planet systems—including 4 planets orbiting the M dwarf K2-72 near mean-motion resonances. By quantifying the likelihood that each candidate is a planet we demonstrate that our candidate sample has an overall false positive rate of 15%-30%, with rates substantially lower for small candidates (\lt 2{R}\oplus ) and larger for candidates with radii \gt 8{R}\oplus and/or with P\lt 3 {{days}}. Extrapolation of the current planetary yield suggests that K2 will discover between 500 and 1000 planets in its planned four-year mission, assuming sufficient follow-up resources are available. Efficient observing and analysis, together with an organized and coherent follow-up strategy, are essential for maximizing the efficacy of planet-validation efforts for K2, TESS, and future large-scale surveys.
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