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To constitute a factor linked to the permanence of the student at the university, the communicative skills install a concerning focus in several institutions. Since this assumption, this article, inscribed in the research project "Youth and Speech, Academic literacy and apprenticeship genres" in the Education Sciences School, endorsed by the Research, Science and Method Secretary of the Faculty of Philosophy and Humanities of the National University of Córdoba for the 2018-2019 biennium, deals with a qualitative perspective via self-reporting questionnaires the strategies of the Basic Cycle students when it comes to preparing their on-site, mid-term exams. For this purpose, it retrieves three core concepts: 1) academic enculturation-literacy (Bombini, 2017); 2) Student genres o text types aimed to instruction (Gardner & Nesi 2013; Navarro, 2014; Labeur & Bombini, 2017); and the university mid-term exam. (Grigüelo, 2005; Natale & Stagnaro, 2014) Although the material is at an analysis process, as a planned conclusion it could anticipate an extensive work with drafts that proofs writing planning and recursion, but also a limited contextualization from the texts offered by lectureships and a weakness that resides on the near absence of the rethoric and pragmatic dimensions. [ABSTRACT FROM AUTHOR]

Numerous new data on a total of 165 bee species from the Spanish provinces of Asturias and León are presented, including one (Nomada obtusifrons Nylander, 1848) that had not previously been reported from the Iberian Peninsula, with several first provincial records and information on the plants these species visit. Comments on the distribution range of the most remarkable species are also included. The paper is illustrated with field photographs of specimens in their natural environment, along with images taken through a binocular microscope showing the diagnostic details of some taxa that are either interesting or difficult to determine. [ABSTRACT FROM AUTHOR]

Bumblebees of the genus Bombus Latreille (Hymenoptera: Apidae) play an important role in maintaining natural ecosystems and agricultural production due to their ability as pollinators. Reduction of their populations and the extinction of some species have been verified in some European countries, in the United States, Brazil, Chile and Argentina. In Uruguay five Neotropical species and one exotic species have been reported. However in the last years only B. pauloensis and B. bellicosus have been found in the country. The aim of this study was to determine the bumblebee species currently present in Uruguay and their distribution in the country. We analyzed 1126 workers collected between 2009 and 2014 in 73 locations covering the 19 provinces of the country. Observation of the sting capsule of the females was used to identify the species. Of the six species reported for Uruguay, only the presence of B. pauloensis and B. bellicosus was confirmed in this study. The first one presented a wide distribution being present in all the provinces, while B. bellicosus was registered only in the south of the country. The results found about B. pauloensis and B. bellicosus distributions constitute a base line to monitor in the future the distribution of these species which face several challenges that threaten their populations. This information will be essential to develop appropriate management and protection strategies for these species. [ABSTRACT FROM AUTHOR]

The effect of insecticides on bees has gained great attention, however, there are few studies that explore this issue on Neotropical bees. Bombus atratus is a neotropical species broadly distributed in Colombia and is considered an important pollinator of both Andean ecosystems and agroecosystems. However, as for many wild bees species, the effect of insecticides on B. atratus is unknow. In this study we determined the acute median lethal dose (LD50) of commercial formulations of insecticides Imidacloprid, Spinosad and Thiocyclam hydrogen oxalate, widely used in Colombia to control several pests of important crops. The LD50 was carried out by oral and contact routes, following and modifying the EPPO and OECD guidelines to perform LD50 on A. mellifera. We evaluated five doses for each route and insecticide, in a total of 25 medium-size workers for each dose by duplicate. Mortality was registered at 24, 48 and 72 hours after the experiment; and data were analyzed with the Probit regression model. For Imidacloprid, contacts and oral LD50 were 0.048 μg/bee and 0.010 μg/bee, respectively. For Thiocyclam hydrogen oxalate, topical and oral LD50 were 0.244 μg/bee and 0.056 μg/bee, respectively. For Spinosad, the oral LD50 corresponded to 0.28 μg/bee; it was not possible to establish the LD50 for the contact route. The Hazard Quotient (HQ) and Index of Relative Toxicity indicated that all three active ingredients are highly toxic. We discussed the risk of the insecticides use on B. atratus, considering their chemical nature. [ABSTRACT FROM AUTHOR]

Nectary structure, nectar-chemical composition, and floral visitors were studied in natural populations of the monotypical genus Ligaria Tieghem. Blooming takes place from autumn to spring. Flowers are perfect, hexamerous, actinomorphic, chasmogamous, and protandrous. The showy red monochlamideous perianth forms a tube in its lower part due to interwoven papilla-like epidermal cells from contiguous repels. Stamens are adnate to the tube and anthers are dorsifixed and versatile. The ovary is inferior and the style is cylindrical bearing a stylar nectary in its base. Hemiparacytic stomata were found on the apical part of the nectary. This species is hummingbird-pollinated. Chlorostilbon aureoventris was observed cropping nectar. These hummingbirds tend to be intra-specifically territorial. Bumblebees (Xylocopa sp.) are L. cuneifolia (R. et P.) Tieghem nectar-robers piercing the tubular base of the perianth to take the nectar. Considering the nectar chemical composition, no significant variation was detected among the three studied samples of Ligaria growing on three different host plants. The mean sugar nectar composition was found to be of a sucrose-dominant species: 56.5%, 15.9%, and 27.5% for sucrose, fructose, and glucose respectively. Amino acids, lipids, reducing acids, and phenols were detected in all samples, whereas alkaloids and proteins were not. The range of sugar concentration was 28-36% according to the sample. [ABSTRACT FROM AUTHOR]