219 research outputs found
Review of high-contrast imaging systems for current and future ground- and space-based telescopes I. Coronagraph design methods and optical performance metrics
The Optimal Optical Coronagraph (OOC) Workshop at the Lorentz Center in
September 2017 in Leiden, the Netherlands gathered a diverse group of 25
researchers working on exoplanet instrumentation to stimulate the emergence and
sharing of new ideas. In this first installment of a series of three papers
summarizing the outcomes of the OOC workshop, we present an overview of design
methods and optical performance metrics developed for coronagraph instruments.
The design and optimization of coronagraphs for future telescopes has
progressed rapidly over the past several years in the context of space mission
studies for Exo-C, WFIRST, HabEx, and LUVOIR as well as ground-based
telescopes. Design tools have been developed at several institutions to
optimize a variety of coronagraph mask types. We aim to give a broad overview
of the approaches used, examples of their utility, and provide the optimization
tools to the community. Though it is clear that the basic function of
coronagraphs is to suppress starlight while maintaining light from off-axis
sources, our community lacks a general set of standard performance metrics that
apply to both detecting and characterizing exoplanets. The attendees of the OOC
workshop agreed that it would benefit our community to clearly define
quantities for comparing the performance of coronagraph designs and systems.
Therefore, we also present a set of metrics that may be applied to theoretical
designs, testbeds, and deployed instruments. We show how these quantities may
be used to easily relate the basic properties of the optical instrument to the
detection significance of the given point source in the presence of realistic
noise.Comment: To appear in Proceedings of the SPIE, vol. 1069
Revision of the genus Tapholeon Wells, 1967 (Copepoda, Harpacticoida, Laophontidae)
To date, only two species are known in the laophontid genus Tapholeon Wells, 1967 (Copepoda, Harpacticoida). In the present contribution, a redescription of the type species T. ornatus Wells, 1967, based on the type material, is provided. Furthermore, two new species are described from the coast of Kenya, T. inconspicuus sp. nov. and T. tenuis sp. nov. Two species, formerly attributed to Asellopsis Brady and Robertson, 1873 (namely A. arenicola Chappuis, 1954 and A. chappuisius Krishnaswamy, 1957), are allocated to Tapholeon based on the absence of sexual dimorphism in the swimming legs P2-P4. The former of the two species is redescribed based on additional material from the Comoros. An updated generic diagnosis and a key to the six species of Tapholeon are included
Diferencias intra e inter individuales en inteligencia social de estudiantes portugueses
Social intelligence is a favorable condition for career decision-making and development. The social intelligence indices
of Portuguese students in school years prior to a career transition are characterized and intra and interindividual differences are
analyzed. Participants were 1095 students (552, 50.4% women) with a mean age of 14.78 years (SD = 1.86), in the 8th (542,
49.5%), 10th (295, 26.9%) and 11th (258, 23.6%) grades. The Cognitive Test of Social Intelligence (PCIS) was administered at
two moments, six months apart. Results indicate that the 8th grade obtained higher average scores in Problem Solving, Motivation
and Self-confidence (time 1), while the 10th grade obtained better results in Problem Solving, Motivation and Familiarity (time 2).
Between the assessment moments, all school years register an increase in Problem Solving and Self-confidence in social situations.
These results constitute favorable psychological conditions for the promotion of ethical questioning in career guidance interventions.A inteligência social constitui uma condição favorável à tomada de decisão e ao desenvolvimento vocacional.
Este trabalho visa caracterizar os nÃveis de inteligência social, e analisar as diferenças intra e interindividuais, em alunos
portugueses em anos de pré-transição vocacional. Participaram 1095 alunos (552, 50% mulheres), com uma média de idades
de 14,78 anos (DP = 1,86), do 8º, 10º, e 11º nÃveis escolares. Administrou-se a Prova Cognitiva de Inteligência Social (PCIS),
em dois momentos (T1 e T2), com seis meses de intervalo. Os resultados indicam que o 8º ano obteve resultados médios
superiores, nos Ãndices de Resolução de Problemas, Motivação e Autoconfiança (T1), enquanto o 10º ano obteve resultados
superiores, em Resolução de Problemas, Motivação e Familiaridade (T2). Entre momentos de avaliação, registra-se, para
todos os nÃveis escolares, um aumento em Resolução de Problemas e Autoconfiança em situações sociais. Estes resultados
constituem condições psicológicas favoráveis à promoção do questionamento ético nas intervenções de orientação vocacional.La inteligencia social es una condición favorable para la toma de decisiones y el desarrollo de la carrera. Se
caracterizan los niveles de inteligencia social y sus diferencias intra e interindividuales en estudiantes portugueses en transición
pre-profesional. Participaron 1095 estudiantes (552, 50.4% mujeres) con una edad media de 14.78 (DE = 1.86), del 8º (542,
49,5%), 10º (295, 26.9%) y 11º (258, 23.6%) años escolares. Se administró la Prueba Cognitiva de Inteligencia Social (PCIS) en
dos ocasiones, con seis meses de diferencia. Los resultados indican que los estudiantes del 8º grado obtuvieron puntajes medios
más altos en la Resolución de Problemas, Motivación y Confianza (T1), mientras que los del 10º grado obtuvieron mejores
resultados en la Resolución de Problemas, Motivación y Familiaridad (T2). Entre momentos de evaluación se registra, para
todos los años, un aumento en la Resolución de Problemas y Confianza en situaciones sociales. Estos resultados constituyen
condiciones psicológicas favorables a la promoción del cuestionamiento ético en las intervenciones de orientación profesional.Project coordinated by the fourth author and co-funded by the
Foundation for Science and Technology and the Compete Program -
PTDC/CPE-CED/098896/200
Self-Reported Serious Illnesses in Rural Cambodia: A Cross-Sectional Survey
BACKGROUND: There is substantial evidence that ill-health is a major cause of impoverishment in developing countries. Major illnesses can have a serious economic impact on poor households through treatment costs and income loss. However, available methods for measuring the impact of ill-health on household welfare display several shortcomings and new methods are thus needed. To understand the potential complex impact of major illnesses on household livelihoods, a study on poverty and illness was conducted in rural Cambodia, as part of an international comparative research project. A cross-sectional survey was performed to identify households affected by major illness for further in-depth interviews. METHODOLOGY AND PRINCIPAL FINDINGS: 5,975 households in three rural health districts were randomly selected through a two-stage cluster sampling and interviewed. 27% of the households reported at least one member with a serious illness in the year preceding the survey and 15% of the household members reported suffering from at least one serious illness. The most reported conditions include common tropical infectious diseases, chronic diseases (notably hypertension and heart diseases) and road traffic accidents. Such conditions were particularly concentrated among the poor, children under five, women, and the elderly. Poor women often reported complications related to pregnancy and delivery as serious illnesses. CONCLUSIONS AND SIGNIFICANCE: Despite some methodological limitations, this study provides new information on the frequency of self-reported serious illnesses among the rural Cambodia's population, which serves as a basis for further in-depth investigation on 'major illnesses' and their economic consequences on poor households. This can in turn help policy makers to formulate appropriate interventions to protect the poor from the financial burden associated with ill-health. Our findings suggest that every year a considerable proportion of rural population in Cambodia, especially the poor and vulnerable, are affected by serious illnesses, both communicable and non-communicable diseases
Major basic protein, but not eosinophil cationic protein or eosinophil protein X, is related to atopy in cystic fibrosis
Ameiridae Boeck and Argestidae Por revisited, with establishment of Parameiropsidae, a new family of Harpacticoida (Crustacea, Copepoda) from deep-sea sediments
Coronagraphy for segmented apertures: results from demonstrations on the HICAT testbed
Instrumentatio
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