Directional bias of illusory stream caused by relative motion adaptation

AbstractEnigma is an op-art painting that elicits an illusion of rotational streaming motion. In the present study, we tested whether adaptation to various motion configurations that included relative motion components could be reflected in the directional bias of the illusory stream. First, participants viewed the center of a rotating Enigma stimulus for adaptation. There was no physical motion on the ring area. During the adaptation period, the illusory stream on the ring was mainly seen in the direction opposite to that of the physical rotation. After the physical rotation stopped, the illusory stream on the ring was mainly seen in the same direction as that of the preceding physical rotation. Moreover, adapting to strong relative motion induced a strong bias in the illusory motion direction in the subsequently presented static Enigma stimulus. The results suggest that relative motion detectors corresponding to the ring area may produce the illusory stream of Enigma

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

Identification du sexe en fonction de l'état de maturité chez les poissons

Le but de ce travail est de mettre au point des techniques permettant de caractériser l'état de maturité et le sexe des poissons (et plus particulièrement des salmonidés) afin de répondre aux sollicitations des Ecologistes pour estimer le potentiel reproducteur des populations naturelles, et des pisciculteurs pour gérer leurs stocks de géniteurs

Growth reproduction interaction in salmonids

International audienc

Poissons d'eau douce : Tometes de Le Bail

Au sein des forêts, des savanes et des marais, dans les rivières, les mangroves ou le domaine marin, la faune de Guyane compte plus de 1500 espèces de vertébrés. L’état des lieux réalisé montre que 166 d’entre elles sont menacées et met en évidence les principales pressions pesant sur la faune et ses habitats naturels

Presence of insulin like growth factor binding protein (IGF-BP) in rainbow trout (Oncorhynchus mykiss) serum

Recombinant human IGF-I (hIGF-I) binding to rainbow trout serum fractions was studied in vitro. Binding protein preparations, from human and trout serum (hBP and tBP), which were obtained using size exclusion chromatography (AcA 54) under acid conditions, were used to characterize IGF binding protein. Mammalian protein binding assay, using hIGF-I as labeled hormone, was optimized (pH, Tris concentration, bound-free I-125-hIGF-I separation conditions by charcoal) for trout serum. The association kinetics (T = 4-degrees-C) of specific binding presented a plateau from 20-30 h, and nonspecific binding remained stable for the same time. Percentage of I-125-hIGF-I which was able to bind to tBP was at least 55%. In the same incubation conditions, hIGF-I binding to trout BP had a higher affinity (Ka = 2.8 10(10) M-1) than those obtained with human BP preparation (Ka = 0.17 10(10) M-1) which contains four molecular forms of BPs. The binding was saturable but its capacity was fourfold lower in trout (Bmax = 410 ng/ml of serum) than in human (Bmax = 1868 ng/ml) serum. Binding to trout BP is very specific for human IGF-I and for trout IGF serum extract. hIGF-II crossreacts partially but no binding was observed with porcine insulin. When trout serum was chromatographed on an analytic AcA 54 column (1 x 100 cm), the maximum hIGF-I activity was found in a peak which corresponded to 55 kDa. Two other peaks (34 and 23 kDa) also bound hIGF-I, but with a much lower activity. In Western-ligand-blot from SDS-PAGE, binding of I-125-hIGF-I to trout serum presented a major band (MW = 41.5 kDa) similar to the biggest form of IGF-BP-3 from human serum. These results suggest that IGF binding protein(s) exists in trout serum but the majority of IGF binding activity is carried only by one form (41.5 kDa), in contrast to mammals which have four forms of BP with a similar magnitude of serum concentration

Growth hormone and thyroid hormone levels during smolting in different populations of atlantic salmon

International audienc

Techniques d'identification du sexe et d'estimation de la maturite sexuellechez les poissons vivants

National audienc

Analyse et conception de systèmes de production végétale à l'échelle des bassins d'approvisionnement agro-alimentaires

Comme pour les questions environnementales, la gestion des productions agricoles requiert l'analyse du fonctionnement d'un territoire, ici le bassin d'approvisionnement agro-alimentaire, pour le diagnostic et la conception de nouvelles organisations de la production adaptées aux évolutions des demandes et des ressources. On montre que la simple somme des comportements individuels des agriculteurs et des utilisateurs de leurs récoltes ne suffit pas à dégager des solutions durables. L'article illustre les outils et les méthodes de l'agronome pour l'analyse de ces systèmes d'approvisionnement dans leurs trois composantes complémentaires : les composantes physiques et agricoles des bassins d'approvisionnement; les stratégies, objectifs et ressources des entreprises qui en constituent les acteurs ; les outils et dispositifs de coordination qui les organisent et contribuent à l'atteinte de leurs objectifs. Deux études de cas illustrent l'intérêt de ces démarches interdisciplinaires pour l'aide à la décision des acteurs privés ou publics