Hard X-ray emitting energetic electrons and photospheric electric currents

The energy released during solar flares is believed to be stored in non-potential magnetic fields associated with electric currents flowing in the corona. While no measurements of coronal electric currents are presently available, maps of photospheric electric currents can now be derived from SDO/HMI observations. Photospheric electric currents have been shown to be the tracers of the coronal electric currents. Particle acceleration can result from electric fields associated with coronal electric currents. We revisit here some aspects of the relationship between particle acceleration in solar flares and electric currents in the active region. We study the relation between the energetic electron interaction sites in the solar atmosphere, and the magnitudes and changes of vertical electric current densities measured at the photospheric level, during the X2.2 flare on February 15 2011 in AR NOAA 11158. X-ray images from RHESSI are overlaid on magnetic field and electric current density maps calculated from the spectropolarimetric measurements of SDO/HMI using the UNNOFIT inversion and Metcalf disambiguation codes. X-ray images are also compared with EUV images from SDO/AIA to complement the flare analysis. Part of the elongated X-ray emissions from both thermal and non-thermal electrons overlay the elongated narrow current ribbons observed at the photospheric level. A new X-ray source at 50-100 keV (produced by non-thermal electrons) is observed in the course of the flare and is cospatial with a region in which new vertical photospheric currents appeared during the same period (increase of 15%). These observational results are discussed in the context of the scenarios in which magnetic reconnection (and subsequent plasma heating and particle acceleration) occurs at current-carrying layers in the corona

Vision as OfferingInterview of Kamau Daaood Monday April 9, 2012, by Nicole Ollier and Sophie Rachmuhl, edited by Sophie Rachmuhl and Kamau Daaood

The Journey into a Poem Interviewers: Could you tell us how you work? There are several kinds of poems it seems, like the one about your father or the one about Lady Day, which are a bit more narrative than some others. And the one that you start your concerts with, “Liberator of the Spirit,” (hear it on youtube at: https://www.youtube.com/watch?v=4btOXkGpwA8) maybe that’s less narrative. Kamau Daaood: You know the writing process with me is different. There’s no one set way that I write. I’..

Enhancing strategic management using a quantified VRIO: Adding value with the MCDA approach

The field of strategic management has been popularized since the 1960s, as an aid for the search of success factors amongst the internal and external surroundings of an organization. Strategic management has observed and created strategies that are considered as pillars in the present way of applying contemporary management operations. Even though strategic management relies on managers’ capability to comprehend the current economic trends, this area has left a variety of questions unanswered, especially regarding the analyses of the combination of quantitative and qualitative decision criteria. This dissertation aims to enhance strategic management by developing a quantified valuable, rare, inimitable and organized (VRIO) framework, with the aid of the multiple criteria decision analysis (MCDA) approach. To accomplish this objective, the VRIO framework is combined with the Choquet integral (CI) and a real-life application is carried out to support strategic management. The dual methodology used in this dissertation offers an innovative process for business improvement. The benefits and limitations are also presented and discussed

Leptin receptor in the chicken ovary: potential involvement in ovarian dysfunction of ad libitum-fed broiler breeder hens

In hens, the ovarian follicles committed to ovulation are arranged in an ordered follicular hierarchy. In standard broiler breeders hens genetically selected for high growth rate the reproductive function is clearly dysfunctional. Feed restriction is needed during reproductive development to limit the formation of excessive numbers of ovarian yellow follicles arranged in multiple hierarchies. To determine whether leptin is involved in the nutritional and reproductive interactions controlling follicular hierarchy in hens, blood leptin levels and ovarian expression of the leptin receptor mRNA were determined during follicle maturation in three chicken lines; a slow growing broiler "Label" genotype without reproductive dysfunction, a fast growing "Standard" genotype fed ad libitum or restricted and a fast growing "Experimental" line with intermediate reproductive performance levels. Whereas expression of the leptin receptor mRNA did not change in the theca, it clearly decreased with follicular differentiation in the granulosa of slow growing hens. In fast growing standard hens fed ad libitum and presenting significant reproductive dysfunction, the decrease was disrupted and dramatic up-regulation of granulosa cell expression of the leptin receptor was observed. On the other hand, feed restriction decreased the overall level of expression of the leptin receptor mRNA and restored the decrease with follicular growth. The level of expression of the leptin receptor probably modulates the action of leptin on follicular differentiation. Since blood leptin and other metabolic factors were not affected by the genotype or by nutritional state, the factors involved in the regulation of leptin receptor gene expression remain to be determined. This study demonstrates the involvement of leptin in the nutritional control of reproduction in birds. Leptin action on the ovary probably controls follicular hierarchy through the regulation of steroidogenesis

The impact of observation spatial and temporal densification in an ensemble Kalman Filter

Hydrodynamic

Digital Remembrance: Archives and the 100th Anniversaries of World War I

These presentations were part of panel at MARAC Buffalo in October of 2017. The title of the panel was Digital Remembrance: Archives and the 100th Anniversaries of World War I. The panel looked at using modern approaches to digitization and audience engagement in service of remembering WWI and those impacted by the war - families, volunteers and soldiers

Disparités interindustrielles dans les taux de départs volontaires : une étude empirique

L’objet de cet article est d’utiliser le modèle d’estimation LISREL dans l’étude empirique des départs volontaires au Québec. Il s’agit d’un modèle d’estimation de coefficients inconnus d’un ensemble d’équations structurelles linéaires avec variables latentes. Les données utilisées sont au niveau de l’industrie. Elles portent sur l’année 1982 et proviennent de diverses sources.Le modèle estimé contient trois variables endogènes latentes : les départs volontaires, les occasions économiques et les facteurs de risque. Le modèle retient aussi dix variables exogènes portant sur les caractéristiques personnelles des travailleurs, leur formation, leur milieu de travail et l’état des relations de travail. La majorité des résultats obtenus confirment nos anticipations. Par ailleurs, nous avons trouvé un résultat très significatif voulant que les « facteurs de risque » (indice composé de l’incidence et de la gravité des accidents du travail) réduisent les départs volontaires. Ce résultat s’ajoute au peu de résultats empiriques à ce sujet, mais est contraire à ces derniers. Nous avons donc été amenés à examiner de plus près les fondements théoriques des attentes sur cette relation pour en conclure que l’attente traditionnelle d’une relation positive n’était pas fondée et que l’on pouvait tout à fait appuyer une relation négative entre les « facteurs de risque » et les départs volontaires.Notre analyse détaillée des résultats empiriques fait ressortir l’intérêt du modèle LISREL dans l’étude du phénomène complexe des départs volontaires.Mots clés : départs volontaires, salaires, risques d’accidents, LISREL.This article refers to a LISREL specification to study empirically the determinants of job mobility in Quebec. A LISREL approach is particularly useful for a system of simultaneous equations with latent variables. The industry level data used in this study are for 1982 and combine various statistical sources. The job mobility model includes three endogenous latent variables: job mobility, economic opportunity and risk factors. There are ten exogenous variables associated with labor personal characteristics, human capital, labor environment and labor relations. In general, the results confirm our anticipations. A significative result suggests that risk factors reduce job mobility. This is contrary to previous results, but can be explained from theoretical considerations. The use of LISREL helps to explain the complex issue of job mobility.Key words: job mobility, wages, risk factors, LISREL

MiST: a large-scale annotated resource and neural models for functions of modal verbs in English scientific text

Modal verbs (e.g., can, should or must) occur highly frequently in scientific articles. Decoding their function is not straightforward: they are often used for hedging, but they may also denote abilities and restrictions. Understanding their meaning is important for accurate information extraction from scientific text.To foster research on the usage of modals in this genre, we introduce the MIST (Modals In Scientific Text) dataset, which contains 3737 modal instances in five scientific domains annotated for their semantic, pragmatic, or rhetorical function. We systematically evaluate a set of competitive neural architectures on MIST. Transfer experiments reveal that leveraging non-scientific data is of limited benefit for modeling the distinctions in MIST. Our corpus analysis provides evidence that scientific communities differ in their usage of modal verbs, yet, classifiers trained on scientific data generalize to some extent to unseen scientific domains