Modernizing irrigation operations: Spatially differentiated resource allocations.

Water resource management / Irrigation canals / Property rights / Privatization / Social organization / Social participation / Leadership / Land ownership / Farmers' associations / Water users' associations / Equity / Farmer-agency interactions / Pakistan

Generic typology for irrigation systems operation

Irrigation management / Irrigation systems / Water use efficiency / Canals / Operations / Typology / Water delivery / Water distribution / Water conveyance / Water storage / Irrigation effects / Environmental effects / Gravity flow / Hydraulics / Constraints / Water supply / Networks / Case studies / Sri Lanka

Information techniques for irrigation systems: Selected proceedings of the Second International Network Meeting on Information Techniques for Irrigation Systems held in Lahore/Bahawalnagar, Pakistan, 5-8 December 1994

Irrigation management / Irrigation systems / Decision support tools / Decision making / Information systems / Computer techniques / Models / Water management / Malaysia / Pakistan / Sri Lanka

Physiological responses to temperature in Merizodus soledadinus (Col., Carabidae), a subpolar carabid beetle invading sub-Antarctic islands

International audienceRecent human activities and rising air temperature have increased the vulnerability of sub-Antarctic islands to alien species. At the Kerguelen Islands, the predaceous ground beetle Merizodus soledadinus is the only invasive insect originating from the southern cold temperate area (native from Patagonia, Tierra del Fuego and Falkland Islands). This austral origin raises the question of the limits of its physiological tolerance and capability to withstand (1) global change and (2) warmer climates of archipelagos where its accidental transportation could be facilitated from the Kerguelen Islands (namely Amsterdam and Saint Paul). Using gas chromatography/mass spectrometry metabolomics, we compared metabotypes of adults exposed to different temperatures (0, 4, 8, 12, 16, 20 °C). All individuals survived after 2 weeks regardless of the temperature they were exposed to. The physiological changes observed were consistent with increased metabolic rate at increased temperatures, without extreme metabotypes that are characteristic of acute stress. First cues of sublethal stress were observed after prolonged exposure to 20 °C, a warm regime unrealistic for such duration in sub-Antarctic Islands. Overall, M. soledadinus’ thermal tolerance exceeded temperatures currently experienced in nature, suggesting that climate warming may boost its invasion by eliciting its activity and broadening habitat suitability in both invaded and still pristine islands. This thermal tolerance may allow survival aboard ships and development in sub-Antarctic islands with conditions warmer than the Kerguelen Islands, such as Amsterdam and St Paul. Stringent biosecurity measures are thus needed to prevent transfer from Kerguelen to these islands. The native range of this predaceous beetle limited to the Falkland Islands and southernmost South America may be partly constrained by factors other than temperature, such as desiccation, predation or competitio

Utilisation d’outils interactifs de médiation et enrichissement de l’expérience de visite muséale

This research focuses on the use of interactive mediation tools during the art museum visit which is perceived by professional almost as a necessity. Is the museum visit experience influenced (positively or negatively) by the art museum audiences use of interactive mediation tools ? Which dimensions are concerned ? First, we present the experience and interactivity concepts that constitute our reseach theoretical foundations. Second, we analyse the results from the qualitative method we implemented. On a managerial level, the goal is to help museum professionnals to choose interactive mediation tools in order to satisfy and broaden their audiences

Assessing the museum visit experience

This contribution explores the influence of interactive mediation tools on the art museum visit experience. Its theoretical foundations are the consumption experiential approach (Bourgeon et Filser, 1995 ; Filser, 2002 ; Holbrook et Hirschman, 1982 ; Roederer, 2008) and the museum interactive visit experience (Doering et al. , 1999; N’Gary et Petr, 2012 ; Pallud et Monod, 2010 ; Walls et al. , 2011). We propose the development of a scale to measure the art museum visit experience. On a managerial level, this study may help museum professionnals to reach their different targeted audiences, to measure the contribution of their interactive mediation tools, and consequently increase frequentation

Tre1 GPCR initiates germ cell transepithelial migration by regulating Drosophila melanogaster E-cadherin

Despite significant progress in identifying the guidance pathways that control cell migration, how a cell starts to move within an intact organism, acquires motility, and loses contact with its neighbors is poorly understood. We show that activation of the G protein–coupled receptor (GPCR) trapped in endoderm 1 (Tre1) directs the redistribution of the G protein Gβ as well as adherens junction proteins and Rho guanosine triphosphatase from the cell periphery to the lagging tail of germ cells at the onset of Drosophila melanogaster germ cell migration. Subsequently, Tre1 activity triggers germ cell dispersal and orients them toward the midgut for directed transepithelial migration. A transition toward invasive migration is also a prerequisite for metastasis formation, which often correlates with down-regulation of adhesion proteins. We show that uniform down-regulation of E-cadherin causes germ cell dispersal but is not sufficient for transepithelial migration in the absence of Tre1. Our findings therefore suggest a new mechanism for GPCR function that links cell polarity, modulation of cell adhesion, and invasion

Chemical Abundance Constraints on White Dwarfs as Halo Dark Matter

We examine the chemical abundance constraints on a population of white dwarfs in the Halo of our Galaxy. We are motivated by microlensing evidence for massive compact halo objects (Machos) in the Galactic Halo, but our work constrains white dwarfs in the Halo regardless of what the Machos are. We focus on the composition of the material that would be ejected as the white dwarfs are formed; abundance patterns in the ejecta strongly constrain white dwarf production scenarios. Using both analytical and numerical chemical evolution models, we confirm that very strong constraints come from Galactic Pop II and extragalactic carbon abundances. We also point out that depending on the stellar model, significant nitrogen is produced rather than carbon. The combined constraints from C and N give $\Omega_{WD} h < 2 \times 10^{-4}$ from comparison with the low C and N abundances in the Ly$\alpha$ forest. We note, however, that these results are subject to uncertainties regarding the nucleosynthesis of low-metallicity stars. We thus investigate additional constraints from D and $^4$He, finding that these light elements can be kept within observational limits only for \Omega_{WD} \la 0.003 and for a white dwarf progenitor initial mass function sharply peaked at low mass (2$M_\odot$). Finally, we consider a Galactic wind, which is required to remove the ejecta accompanying white dwarf production from the galaxy. We show that such a wind can be driven by Type Ia supernovae arising from the white dwarfs themselves, but these supernovae also lead to unacceptably large abundances of iron. We conclude that abundance constraints exclude white dwarfs as Machos. (abridged)Comment: Written in AASTeX, 26 pages plus 4 ps figure