Automatic Detection of Expanding HI Shells Using Artificial Neural Networks

The identification of expanding HI shells is difficult because of their variable morphological characteristics. The detection of HI bubbles on a global scale therefore never has been attempted. In this paper, an automatic detector for expanding HI shells is presented. The detection is based on the more stable dynamical characteristics of expanding shells and is performed in two stages. The first one is the recognition of the dynamical signature of an expanding bubble in the velocity spectra, based on the classification of an artificial neural network. The pixels associated with these recognized spectra are identified on each velocity channel. The second stage consists in looking for concentrations of those pixels that were firstly pointed out, and to decide if they are potential detections by morphological and 21-cm emission variation considerations. Two test bubbles are correctly detected and a potentially new case of shell that is visually very convincing is discovered. About 0.6% of the surveyed pixels are identified as part of a bubble. These may be false detections, but still constitute regions of space with high probability of finding an expanding shell. The subsequent search field is thus significantly reduced. We intend to conduct in the near future a large scale HI shells detection over the Perseus Arm using our detector.Comment: 39 pages, 11 figures, accepted by PAS

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Les niveaux de responsabilité dans l’intervention : L’exemple du suicide en milieu carcéral

Lorsque survient un suicide en milieu carcéral, le débat sur le partage des responsabilités se situe à au moins quatre niveaux qui ne sont pas toujours très explicites : celui de la société, en général, celui des institutions, celui des intervenants actifs dans ces institutions et, finalement, celui des personnes incarcérées elles-mêmes (qu’elles soient suicidaires ou pairs de suicidaires). Nous sommes tous interpellés à ces différents niveaux et, par-delà la culpabilisation qui pourrait en résulter, notre prise de conscience devrait plutôt nous amener à agir, de façon cohérente et proactive, dans les différentes sphères où nous pouvons avoir une emprise.When a suicide occurs in a prison environment, the debate on the sharing of responsibilities lies on four levels that are not always explicit: the societal level, in general, the institutional level, the level of caregivers working in these institutions and, lastly, the level of the incarcerated individuals themselves, either being suicidal or being the peer of a suicidal person. We are all called upon at these different levels and, beyond the placing guilt that may result, our awareness of the situation should rather bring us to take action, consistently and proactively, in the various spheres in which we may have some influence

Troubles mentaux et tentatives de suicide chez les détenus. Le rôle du trouble du déficit de l’attention avec hyperactivité

En milieu carcéral, la prévalence des troubles mentaux et des décès par suicide atteint des proportions largement supérieures à celles de la population générale, le risque de mourir par suicide étant de 11 à 14 fois plus élevé. À partir d’un échantillon de 565 individus nouvellement incarcérés, le lien entre les tentatives de suicide et les troubles mentaux a été étudié, en mettant l’accent sur le trouble du déficit de l’attention avec hyperactivité (TDAH). Les résultats démontrent que la présence possible d’un TDAH chez un détenu augmente la probabilité d’avoir déjà fait une tentative de suicide, au même titre que la présence d’un trouble de l’Axe I ou II.In prisons, the prevalence of mental disorders and death by suicide reach proportions far above that of the general population : the risk of suicide being 11 to 14 times higher. Based on a sample of 565 newly incarcerated individuals, the relationship between suicide attempts and mental disorders was studied, with an emphasis on the attention deficit hyperactivity disorder (ADHD). Results show that a possible presence of ADHD in a prisoner increases the likelihood of having already attempted suicide, as well as the presence of an Axis I and II disorders.En el medio carcelario, la prevalencia de trastornos mentales y de decesos por suicidio alcanza proporciones altamente superiores a aquélla de la población general ; el riesgo de morir por suicidio es de 11 a 14 veces más elevado. A partir de una muestra de 565 individuos recientemente encarcelados, ha sido estudiada la relación entre los intentos de suicidio y los trastornos mentales, poniendo énfasis sobre el trastorno de déficit de atención e hiperactividad (TDAH). Los resultados demuestran que la presencia posible de un TDAH en un detenido aumenta la probabilidad de haber realizado ya una tentativa de suicidio, al igual que la presencia de un trastorno del Eje I o II

2002 Research Honors Program Abstracts

Faculty in the College of Agriculture and Life Sciences at Cornell University mentor and guide undergraduate students who have chosen to pursue a research project and graduate with honors. These abstracts reflect the depth of their scholarship and intellectual ability. The research projects encompass work in animal science, biological science, entomology, natural resources, physical science, plant science, and social science