Identification des non-usagers de la bibliothèque HEIG-VD et de leurs besoins documentaires

La bibliothèque de la HEIG-VD à Yverdon-les-Bains a observé que son taux de pénétration était trop faible et a donc décidé d’identifier ses non-usagers et leurs besoins documentaires. A travers une enquête comprenant des questionnaires et des entretiens, le taux de non-usagers et leurs raisons de non-venue ont été identifiés, ainsi que les potentielles améliorations que la bibliothèque devrait effectuer afin de les faire venir. Le taux de participation élevée des non-usagers lors de l’enquête prouve qu’il n’y a pas un rejet de la bibliothèque et que cette thématique intéresse. Cette enquête a révélé que les non-usagers sont rarement conscients de leurs besoins documentaires, ou du moins pensent que les moteurs de recherche sur le Web sont suffisants pour pallier la bibliothèque. Le positionnement géographique a été confirmé comme un obstacle incontournable à la fréquentation. Grâce à l’analyse des résultats de l’enquête, ainsi qu’à l’état de l’art, des recommandations d’améliorations tels que des formations ou un service de référence en ligne ont été élaborées en tenant compte des contraintes de la bibliothèque. Ce travail démontre que ces recommandations ne peuvent être efficientes que si la bibliothèque est intégrée dans une stratégie globale de l’école

Musicothérapie et maladie d'Alzheimer: quels sont ses effets sur les symptômes comportementaux et psychologiques de la démence ?

A l’heure actuelle, la population vieillissante, en fulgurante croissance, développe des pathologies chroniques et des démences liées à l’âge. La démence la plus répandue est la maladie d’Alzheimer. Celle-ci s’accompagne de symptômes comportementaux et psychologiques (SCPD) qui engendrent une difficulté dans la prise en charge. Bien souvent, la gestion des manifestations se fait par le biais de médicaments lourds en effets secondaires. La musicothérapie peut être une alternative

Seasonal patterns in species diversity across biomes

A conspicuous season–diversity relationship (SDR) can be seen in seasonal environments, often with a defined peak in active species diversity in the growing season. We ask is this a general pattern and are other patterns possible? In addition, we ask what is the ultimate cause of this pattern and can we understand it using existing ecological theory? To accomplish this task, we assembled a global database on changes in species diversity through time in seasonal environments for different taxa and habitats and also conducted a modeling study in an attempt to replicate observed patterns. Our global database includes terrestrial and aquatic habitats, temperate, tropical, and polar environments, and taxa from disparate groups including vertebrates, insects, and plankton. We constructed nine alternative models that vary in assumptions on type of seasonal forcing, responses to that forcing, species niches, and types of species interactions. We found that most guilds of species exhibit a repeatable SDR across years. For north temperate ecosystems, active species diversity generally peaks mid‐year. The peak for a guild is generally more pronounced in terrestrial habitats than aquatic habitats and more pronounced in temperate and polar regions than the tropics. We now have evidence that at least several different habitat and taxa types are likely to have multiple peaks in diversity in a year, for example, guilds of both aquatic microbes and desert vertebrates can show a bimodal or multimodal SDR. We compared all nine candidate models in their ability to explain the patterns and match their assumptions to the data. Some performed considerably better than others in being able to match the different patterns. We conclude that a model that includes both temperature niches and environmental feedbacks is necessary to explain the different SDRs. We use such a model to make predictions about how the SDR could be impacted by climate change. More effort should be put into documenting and understanding baseline seasonal patterns in diversity in order to predict future responses to global change

On the existence of a dynamic critical point by using wet milling on (±) modafinil

This study has been carried out on the molecular compound (±) modafinil, which exhibits five pure polymorphic forms (I, III, IV, V and VI). At P = 1 atm, irrespective of temperature and without any milling energy, Form I is the stable form. Therefore, the other polymorphic forms (III, IV, V and VI) are of monotropic character. The steady states of (±) modafinil have been investigated as a function of wet milling parameters (milling intensity and water concentration). The results presented here suggest the existence of a dynamic critical point defined by Tc ≈ 40°C, Pc ≈ 1 atm, Ic ≈ k R; R=50, Xc = 2% mass percent of water, respectively the critical: mean temperature, global pressure, milling intensity proportional to R and water composition (in mass percent)

Diffusion Of Indigo Molecules Inside The Palygorskite Clay Channels

The search for durable dyes led several past civilizations to develop artificial pigments. Maya Blue (MB), manufactured in pre-Columbian Mesoamerica, is one of the best known examples of an organic-inorganic hybrid material. Its durability is due to the unique association of indigo molecule and palygorskite, a particular fibrous clay occurring in Yucatan. Despite 50 years of sustained interest, the microscopic structure of MB and its relation to the durability remain open questions. Combining new thermogravimetric and synchrotron X-ray diffraction analyses, we show that indigo molecules can diffuse into the channel of the palygorskite during the heating process, replacing zeolitic water and stabilizing the room temperature phases of the clay

Looking for the vector of the latest discovered geminivirus genus, Capulavirus. [P.48]

Viral metagenomics studies based on virion-associated nucleic acid extraction, sequence-independent amplification and next generation sequencing proved to be effective for discovering three highly divergent geminiviruses in South Africa, France and Finland. Although these geminiviral sequences were isolated from different continents, hemispheres and plant families, including Euphorbia caput-medusae (Euphorbiaceae), Medicago sativa (Fabaceae) and Plantago lanceolata (Plantaginaceae), they were clustered in the same phylogenetic group and were highly divergent from all the sequences classified in the seven established geminivirus genera. Based on sequence relatedness and genome organization, these new highly divergent geminivirus species were provisionally classified in a new geminivirus genus, tentatively named "Capulavirus". To estimate the epidemiological potential of these new geminiviruses but also to confirm their classification according to the criteria defined by the International Committee on Taxonomy of Viruses, including insect vector and host range, further studies were done with two capulaviruses available in our laboratory: Euphorbia caput medusae latent virus (EcmLV) from South Africa (Bernardo et al. 2013) and a capulavirus isolated from alfalfa in France provisionally named Alfalfa leaf curl virus (ALCV) according to the symptoms observed on infected plants. ALCV may cause yield losses because the infected plants exhibited stunting and distorted growth. ALCV was detected in Camargue, Provence Alpes Côte d'Azur, Languedoc Roussillon and Midi-Pyrénées. An infectious clone of EcmLV was prepared and used to determine the host range of EcmLV and test various phloem feeding insects reared in our laboratory, for vector transmission. Potentially infectious clones are presently prepared for ALCV for similar tests. In the meantime, a naturally infected alfalfa plant was transferred to a growth chamber and used as source plant for vector transmission. Potential vectors were also collected from infected alfalfa fields for testing ALCV transmission to alfalfa seedlings prepared in insect proof conditions. (Résumé d'auteur