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The Daniel K. Inouye Solar Telescope (DKIST) advances studies of solar magnetism through high-precision and accuracy in polarimetry at frontier spatial and temporal scales. A system model for polarization response in azimuth and altitude has been developed to calibrate DKIST instruments. The DKIST team has developed several new modeling and performance-estimation techniques coupled with thorough metrology. These efforts ensure that quality polarimetry is delivered to meet stringent accuracy requirements. A custom spectropolarimetric calibration system was designed, installed, and used to perform end-to-end calibration of the telescope using the beam within the Cryo-NIRSP instrument. Extensive optical and polarization characterization efforts allow for the reduction of systematic errors within a detailed system model that includes elliptical calibration retarders. Coating witness samples for every relevant optic in the system have been measured. Aperture-dependent variations in polarizer, retarder, and optic-coating performance have been measured and used to simulate both the polarization dependence on field angle and errors within the optical-system model. Multiple observations on-Sun and with a calibration lamp agree well with each other and with the system model. Upcoming multi-instrument observations are expected to be well calibrated with detailed understanding of major error limitations. [ABSTRACT FROM AUTHOR]

From the mid-1950s to the present time, creativity researchers have typically adopted the view that any new piece of work must be statistically novel as well as non-trivially valuable to some group of people if it is to be considered creative. A few scholars have suggested that a new piece of work must also be surprising, non-obvious, or interesting if it is to be considered truly creative. The utility of these traditional definitions of creativity has recently been sharply questioned in an article published in a previous volume of this journal (Weisberg, 2015). The commentary presented here took issue with a suggestion presented in that article that creativity researchers replace their traditional definitions of creativity with a simpler definition according to which any statistically novel and intentionally generated product is considered creative “regardless of whether it is ever of value to anyone” and with a logically related suggestion that the creativity of any intentionally-generated product be assessed purely in terms of its statistical novelty (Weisberg, 2015). After carefully evaluating both of these suggestions on conceptual and practical grounds, it was recommended that creativity researchers not follow either suggestion. [ABSTRACT FROM PUBLISHER]

This exploratory study was designed to expand the field’s understanding of talented adolescent visual artists and creative writers and their conscious motivations for engaging in these creative activities. Accordingly, 233 talented high school visual arts (n = 151) and creative writing (n = 82) students were asked to rate the degree to which they believed their creative activities were motivated by each of a wide range of possible motivations. The students in both fields reported being very strongly motivated by the opportunities their activities provided them to use their imaginations, feel free, sense that they were being their “true” selves, regulate their emotions, capture moments in time, deepen their self-understanding, express themselves, improve their skills, and enhance their self-esteem. Some of these motivations correspond closely to those highlighted by theories of intrinsic motivation, competence motivation, and self-actualization, several are similar to those which have been reported by professional artists and writers, and some suggest that the students may have derived important psychological benefits from their creative activities. Theoretically plausible differences between the motivational profiles of the visual and creative writing students were identified and discussed. [ABSTRACT FROM AUTHOR]

Spectropolarimetric measurements at moderate spectral resolutions are effective tracers of stellar magnetic fields and circumstellar environments when signal-to-noise ratios (S/Ns) above 2000 can be achieved. The LRISp spectropolarimeter is capable of achieving these S/Ns on faint targets with the 10 m aperture of the Keck telescope, provided several instrumental artifacts can be suppressed. We describe here several methods to overcome instrumental error sources that are required to achieve these high S/Ns on LRISp. We explore high S/N techniques such as defocusing and slit-stepping during integration with high spectral and spatial oversampling. We find that the instrument flexure and interference fringes introduced by the achromatic retarders create artificial signals at 0.5% levels in the red channel which mimic real stellar signals and limit the sensitivity and calibration stability of LRISp. Careful spectral extraction and data filtering algorithms can remove these error sources. For faint targets and long exposures, cosmic ray hits are frequent and present a major limitation to the upgraded deep depletion red-channel CCD. These must be corrected to the same high S/N levels, requiring careful spectral extraction using iterative filtering algorithms. We demonstrate here characterization of these sources of instrumental polarization artifacts and present several methods used to successfully overcome these limitations. We have measured the linear to circular cross-talk and find it to be roughly 5%, consistent with the known instrument limitations. We show spectropolarimetric signals on brown dwarfs are clearly detectable at 0.2% amplitudes with sensitivities better than 0.05% at full spectral sampling in atomic and molecular bands. Future LRISp users can perform high-sensitivity observations with high-quality calibration when following the described algorithms. [ABSTRACT FROM AUTHOR]

Objective: The main objective of this study was to describe the visceral and renal vessel involvement and the outcomes in thoracic dissections. Methods: Computed tomography scans of 39 patients were reviewed (30 type B, 9 type A). Visceral and renal arteries were recorded as perfused by the true lumen (TL) or false lumen (FL). Radiologic follow-up was 3.3 years (range 0-10). Results: A total of 156 vessels were analyzed, and 49 (31%) were supplied by the FL. The most common patterns were FL supply of a renal artery (RA) with the visceral arteries and contralateral RA from the TL. In the follow-up, branch vessel compromise occurred in 12 vessels and was more likely to occur when supplied by the FL (P ¼ .01). About 75% of the patients with at least 2 vessels supplied by the FL demonstrated aortic dilatation. Conclusions: Branch vessel occlusion is more likely in the vessels supplied by the FL. Aortic dilatation occurred more frequently when 2 or more vessels were supplied by the FL. [ABSTRACT FROM AUTHOR]

Background: Failure of endovascular repair (EVAR) of an abdominal aortic aneurysm can result in significant risk of morbidity and mortality. We review our experience with late conversions to open repair. Methods: We conducted a retrospective database review to identify all EVAR procedures performed between 1997 and 2010 and the number converted to open repair at our university-affiliated medical centre. Late conversion was defined as those occurring at least 30 days after initial EVAR. Results: In all, 892 EVARs took place during the study period. Six patients (0.7%) required late conversion to open repair. Their mean age was 71 (range 58-83) years, and half were women. Half of the initial EVARs were for ruptured aneurysms. The median time to conversion was 15.6 (range 1.7-61.3) months. Indications for secondary conversion (50% urgent, 50% elective) included persistent type I endoleak (n = 3), combined type II and III endoleak (n = 1), graft thrombosis (n = 1) and aneurysm rupture (n = 1). Supraceliac clamping was required in most patients (67%), and the mean transfusion requirement was 2.6 units. Total endograft explanation occurred in 2 patients (33%), whereas partial or total endograft preservation occurred in 4 (67%). Median length of stay in hospital after conversion was 7 (range 6-73) days. There were no instances of early or in-hospital mortality following conversion. Conclusion: Our EVAR experience includes a low rate of late conversion to open repair, with most conversions being a result of persistent aneurysm perfusion. Al - though technically challenging, late conversion can be safe. Our experience supports ongoing surveillance after EVAR. [ABSTRACT FROM AUTHOR]

Analyzes Hans J. Eysenck's claims about the close alliance between creativity and psychosis in an article published in the periodical 'Psychological Inquiry.' Problematic elevation of cognitive overinclusiveness present in Eysenck's article; Author's questions concerning the psychological meaning of the Psychoticism scale of the Eysenck Personality Questionnaire.

The Diffraction-Limited Near-Infrared Spectropolarimeter (DL-NIRSP) is one of the first-light instruments for the National Science Foundation's Daniel K. Inouye Solar Telescope (DKIST). DL-NIRSP is an integral-field, dual-beam spectropolarimeter intended for studying magnetically sensitive spectral lines in the Sun's photosphere, chromosphere, and corona with high spectral resolution and polarimetric accuracy. Two novel fiber-optic integral-field units (IFUs), paired with selectable feed optics and a field-scanning mirror provide great flexibility in spatial sampling ( 0.03 ″ , 0.08 ″ , and 0.5 ″ ) and field coverage ( 2 ′ × 2 ′ ). The IFUs allow DL-NIRSP to record all the spectra from a 2D field of view simultaneously, enabling the instrument to study the evolution of highly dynamic events. The spectrograph is an all-reflecting, near-Littrow design, which achieves a resolving power of approximately 125,000. Multiple wavelengths can be observed simultaneously using three spectral arms: one for visible wavelengths (500 – 900 nm) and two for infrared wavelengths (900 – 1350 nm and 1350 – 1800 nm). Each supporting camera sub-system is capable of a 30-Hz frame rate, making it possible to track dynamic phenomena on the Sun. [ABSTRACT FROM AUTHOR]

We examined the role of social comparison in changes in the artistic self-concept of adolescents attending an advanced arts programme. Unfavourable comparisons that promoted a sense of inferiority and favourable comparisons that promoted inspiration were measured just prior to, in the first week of, and at the end of the 6 week programme. Consistent with the 'big fish little pond effect', inferiority comparisons made during the programme were associated with negative changes in self-concept. Consistent with the social comparison literature, however, inspiration comparisons made during the programme were associated with positive changes in self-concept. Rather than suggesting that exposure to highly talented peers is necessarily unfavourable, results suggest that the interpretation of the comparisons made in situ determines the favourability of such exposure. [ABSTRACT FROM AUTHOR]

We present an overview of the National Science Foundation's Daniel K. Inouye Solar Telescope (DKIST), its instruments, and support facilities. The 4 m aperture DKIST provides the highest-resolution observations of the Sun ever achieved. The large aperture of DKIST combined with state-of-the-art instrumentation provide the sensitivity to measure the vector magnetic field in the chromosphere and in the faint corona, i.e. for the first time with DKIST we will be able to measure and study the most important free-energy source in the outer solar atmosphere – the coronal magnetic field. Over its operational lifetime DKIST will advance our knowledge of fundamental astronomical processes, including highly dynamic solar eruptions that are at the source of space-weather events that impact our technological society. Design and construction of DKIST took over two decades. DKIST implements a fast (f/2), off-axis Gregorian optical design. The maximum available field-of-view is 5 arcmin. A complex thermal-control system was implemented in order to remove at prime focus the majority of the 13 kW collected by the primary mirror and to keep optical surfaces and structures at ambient temperature, thus avoiding self-induced local seeing. A high-order adaptive-optics system with 1600 actuators corrects atmospheric seeing enabling diffraction limited imaging and spectroscopy. Five instruments, four of which are polarimeters, provide powerful diagnostic capability over a broad wavelength range covering the visible, near-infrared, and mid-infrared spectrum. New polarization-calibration strategies were developed to achieve the stringent polarization accuracy requirement of 5×10−4. Instruments can be combined and operated simultaneously in order to obtain a maximum of observational information. Observing time on DKIST is allocated through an open, merit-based proposal process. DKIST will be operated primarily in "service mode" and is expected to on average produce 3 PB of raw data per year. A newly developed data center located at the NSO Headquarters in Boulder will initially serve fully calibrated data to the international users community. Higher-level data products, such as physical parameters obtained from inversions of spectro-polarimetric data will be added as resources allow. [ABSTRACT FROM AUTHOR]