523 research outputs found
Probing the atmosphere of HD189733b with the Na I and K I lines
High spectral resolution transmission spectroscopy is a powerful tool to
characterize exoplanet atmospheres. Especially for hot Jupiters, this technique
is highly relevant, due to their high altitude absorption e.g. from resonant
sodium (Na I) and potassium (K I) lines. We resolve the atmospheric K
I-absorption on HD189733b with the aim to compare the resolved K I -line and
previously obtained high resolution Na I-D-line observations with synthetic
transmission spectra. The line profiles suggest atmospheric processes leading
to a line broadening of the order of 10 km/s for the Na I-D-lines, and only a
few km/s for the K I-line. The investigation hints that either the atmosphere
of HD189733b lacks a significant amount of K I or the alkali lines probe
different atmospheric regions with different temperature, which could explain
the differences we see in the resolved absorption lines
ObjSim: Lightweight Automatic Patch Prioritization via Object Similarity
In the context of test case based automatic program repair (APR), patches
that pass all the test cases but fail to fix the bug are called overfitted
patches. Currently, patches generated by APR tools get inspected manually by
the users to find and adopt genuine fixes. Being a laborious activity hindering
widespread adoption of APR, automatic identification of overfitted patches has
lately been the topic of active research. This paper presents engineering
details of ObjSim: a fully automatic, lightweight similarity-based patch
prioritization tool for JVM-based languages. The tool works by comparing the
system state at the exit point(s) of patched method before and after patching
and prioritizing patches that result in state that is more similar to that of
original, unpatched version on passing tests while less similar on failing
ones. Our experiments with patches generated by the recent APR tool PraPR for
fixable bugs from Defects4J v1.4.0 show that ObjSim prioritizes 16.67% more
genuine fixes in top-1 place. A demo video of the tool is located at
https://bit.ly/2K8gnYV.Comment: Proceedings of the 29th ACM SIGSOFT International Symposium on
Software Testing and Analysis (ISSTA '20), July 18--22, 2020, Virtual Event,
US
The extended chromosphere of CoRoT-2A: Discovery and analysis of the chromospheric Rossiter-McLaughlin effect
The young G7V dwarf CoRoT-2A is transited by a hot Jupiter and among the most active planet host-stars known to date. We report on the first detection of a chromospheric Rossiter-McLaughlin effect observed in the Ca ii H and K emission-line cores. In Ca ii H and K, the transit lasts 15% longer than that observed in visual photometry, indicating that chromospheric emission extends 100 000 km beyond the photosphere. Our analysis is based on a time series of high-resolution UVES spectra obtained during a planetary transit and simultaneously obtained photometry observed with one of the PROMPT telescopes. The chromospheric Rossiter-McLaughlin effect provides a new tool to spatially resolve the chromospheres of active planet host-stars
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Health-related quality of life in Huntingtonâs Disease patients: a comparison of proxy assessment and patient self-rating using the disease-specific Huntingtonâs Disease health-related quality of life questionnaire (HDQoL)
Huntingtonâs disease (HD) is a fatal, neurodegenerative disease for which there is no known cure. Proxy evaluation is relevant for HD as its manifestation might limit the ability of persons to report their health-related quality of life (HrQoL). This study explored patientâproxy ratings of HrQoL of persons at different stages of HD, and examined factors that may affect proxy ratings. A total of 105 patientâproxy pairs completed the Huntingtonâs disease health-related quality of life questionnaire (HDQoL) and other established HrQoL measures (EQ-5D and SF-12v2). Proxyâpatient agreement was assessed in terms of absolute level (mean ratings) and intraclass correlation. Proxiesâ ratings were at a similar level to patientsâ self-ratings on an overall Summary Score and on most of the six Specific Scales of the HDQoL. On the Specific Hopes and Worries Scale, proxies on average rated HrQoL as better than patientsâ self-ratings, while on both the Specific Cognitive Scale and Specific Physical and Functional Scale proxies tended to rate HrQoL more poorly than patients themselves. The patientâs disease stage and mental wellbeing (SF-12 Mental Component scale) were the two factors that primarily affected proxy assessment. Proxy scores were strongly correlated with patientsâ self-ratings of HrQoL, on the Summary Scale and all Specific Scales. The patientâproxy correlation was lower for patients at moderate stages of HD compared to patients at early and advanced stages. The proxy report version of the HDQoL is a useful complementary tool to self-assessment, and a promising alternative when individual patients with advanced HD are unable to self-report
Green criminology: shining a critical lens on environmental harm
Green criminology provides for inter-disciplinary and multi-disciplinary engagement with environmental crimes and wider environmental harms. Green criminology applies a broad ââgreenââ perspective to environmental harms, ecological justice, and the study of environmental laws and criminality, which includes crimes affecting the environment and non-human nature. Within the ecological justice and species justice perspectives of green criminology there is a contention that justice systems need to do more than just consider anthropocentric notions of criminal justice, they should also consider how justice systems can provide protection and redress for the environment and other species. Green criminological scholarship has, thus, paid direct attention to theoretical questions of whether and how justice systems deal with crimes against animals and the environment; it has begun to conceptualize policy perspectives that can provide contemporary ecological justice alongside mainstream criminal justice. Moving beyond mainstream criminologyâs focus on individual offenders, green criminology also explores state failure in environmental protection and corporate offending and environmentally harmful business practices. A central discussion within green criminology is that of whether environmental harm rather than environmental crime should be its focus, and whether green ââcrimesââ should be seen as the focus of mainstream criminal justice and dealt with by core criminal justice agencies such as the police, or whether they should be considered as being beyond the mainstream. This article provides an introductory overview that complements a multi- and inter-disciplinary article collection dedicated to green criminological thinking and research
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