Évaluation de l’effet insecticide de l’extrait acétonique des feuilles séchées de Calotropis procera Ait. (Asclepiadaceae) chez les adultes de Anopheles gambiae, Maroua (Cameroun)

L’efficacité de l’extrait acétonique des feuilles de Calotropis procera a été évaluée sur les adultes de Anopheles gambiae de la ville de Maroua (Cameroun) par la méthode de la moustiquaire imprégnée. La poudre des feuilles de cette plante a été extraite à l’acétone et dilué à l’hexane à des concentrations suivantes : 8,45mg ; 23,35mg, 42,25mg ; 59,15mg et 84,5mg pour imprégner une surface de moustiquaire de 1,69 cm2. Les parcelles de moustiquaire imprégnées sont fixées à la base des cônes calqués sur le modèle des cônes-OMS. Après 24 heures d’exposition, nous avons obtenu 100% de mortalité des moustiques aux concentrations 59,15mg et 84,5mg. La concentration létale 50 (CL50) est de 3,03 g/m² et l’heure létale 50 (HL50) est de 7 h 31 min17s. Toutefois, ces valeurs de CL50 et HL50 sont très élevées comparativement à la Moustiquaire Imprégnée (MILDA) de l’Insecticide Deltaméthrine (55 mg/m2) qui est à Longue Durée d’Action et efficace à la CL50 de 2,30 x10-4 g/m2 et HL50 de 2h11mn13s. Ce qui signifie que la moustiquaire-MILDA est plus efficace que l’extrait des feuilles de Calotropis procera.Mots clés: Calotropis procera, effet insecticide, moustiquaire imprégnée, Anopheles gambiae, Maroua, Cameroun

Non-commutative geometry and the standard model vacuum

The space of Dirac operators for the Connes-Chamseddine spectral action for the standard model of particle physics coupled to gravity is studied. The model is extended by including right-handed neutrino states, and the S0-reality axiom is not assumed. The possibility of allowing more general fluctuations than the inner fluctuations of the vacuum is proposed. The maximal case of all possible fluctuations is studied by considering the equations of motion for the vacuum. Whilst there are interesting non-trivial vacua with Majorana-like mass terms for the leptons, the conclusion is that the equations are too restrictive to allow solutions with the standard model mass matrix.Comment: 21 pages. v2: some comments improve

Non-commutative fermion mass matrix and gravity

The first part is an introductory description of a small cross-section of the literature on algebraic methods in non-perturbative quantum gravity with a specific focus on viewing algebra as a laboratory in which to deepen understanding of the nature of geometry. This helps to set the context for the second part, in which we describe a new algebraic characterisation of the Dirac operator in non-commutative geometry and then use it in a calculation on the form of the fermion mass matrix. Assimilating and building on the various ideas described in the first part, the final part consists of an outline of a speculative perspective on (non-commutative) quantum spectral gravity. This is the second of a pair of papers so far on this project.Comment: To appear in Int. J. Mod. Phys. A Previous title: An outlook on quantum gravity from an algebraic perspective. 39 pages, 1 xy-pic figure, LaTex Reasons for new version: added references, change of title and some comments more up-to-dat

Distribution and Size of Short-finned Squid (Illex illecebrosus) Larvae in the Northwest Atlantic from Winter Surveys in 1969, 1981 and 1982

During a plankton survey along the edge of the continental shelf south of New Jersey in February 1969. Illex sp. larvae were caught in the vicinity of the Florida Current between Cape Hatteras and central Florida (28°30'N 80° 00'W). The larva from the latter area represents the most southwesterly capture that has been reported to date. Illex sp. larvae were also caught during surveys in February-March of 1981 and 1982 south of Newfoundland in the northern partof the Gulf Stream, the most easterly capture being at 40°09'N 53°00'W and northerly capture at 41°00'N 56°00'W. The larvae taken off Florida were 1.1-6.2 mm mantle length (ML) and those from the region south of Newfoundland were 2.4-6.6 mm. From the observed distribution and sizes of larvae in relation to water masses associated with the Gulf Stream System and in the light of recent observations on Illex illecebrosus spawning in captivity and temperatures required for embryonic development, it is considered that spawning probably occurs pelagically a in the winter months within the Gulf Stream or in the Gulf Stream-Slope Water frontal zone south of Cape Hatteras

Lessons from Expert Focus Groups on how to Better Support Adults with Mild Intellectual Disabilities to Engage in Co-Design

Co-design techniques generally rely upon higher-order cognitive skills, such as abstraction and creativity, meaning they may be inaccessible to people with intellectual disabilities (ID). Consequently, investigators must adjust the methods employed throughout their studies to ensure the complex needs of people with ID are appropriately catered to. Yet, there are a lack of guidelines to support researchers in this process, with previous literature often neglecting to discuss the decisions made during the development of their study protocols. We propose a new procedure to overcome this lack of support, by utilizing the knowledge of “experts” in ID to design a more accessible workshop for the target population. 12 experts across two focus groups were successful in identifying accessibility barriers throughout a set of typical early co-design activities. Recommendations to overcome these barriers are discussed along with lessons on how to better support people with ID to engage in co-design