Comparison of Executive Functions in School Children Aged 7 to 12 Years in a State of Malnutrition Due to Thinness, Risk of Thinness and a Control Group of an Educational Institution of the Locality of Ciudad Bolívar- Bogotá, D.C.

The aim of this research was to compare the neuropsychological performance of executive functions of school children in a state of malnutrition caused by thinness and risk of thinness and a control group of a District educational institution of the locality of Ciudad Bolívar in Bogotá, Colombia. The research used a descriptive cross-sectional comparative design, where children aged between 7 and 12 years were selected based on the diagnosis of malnutrition. The executive functions assessed were fluency, working memory, problem solving, inhibitory control and cognitive flexibility, through the Neuropsychological Battery for Children [ENI, for its Spanish acronym] and the original version of Stroop and Wisconsin tests. Results showed statistically significant differences in executive functioning between the children with thinness, thinness risk and the control group. The students with thinness showed a low performance in verbal fluency, visual fluency, working memory, cognitive flexibility and inhibitory control compared with students in a state of malnutrition due to thinness risk and those with normal weight (control group). In conclusion, a strong association was found between the effect of child malnutrition and poor performance in executive tasks where there is evidence that executive functioning is more affected in children with malnutrition due to thinness (severe malnutrition) than in children with malnutrition due to thinness risk and in those of the control group

Implication of the PAMELA antiproton data for dark matter indirect detection at LHC

Since the PAMELA results on the "anomalously" high positron fraction and the lack of antiproton excess in our Galaxy, there has been a tremendous number of studies advocating new types of dark matter, with larger couplings to electrons than to quarks. This raises the question of the production of dark matter particles (and heavy associated coloured states) at LHC. Here, we explore a very simple benchmark dark matter model and show that, in spite of the agreement between the PAMELA antiproton measurements and the expected astrophysical secondary background, there is room for large couplings of a WIMP candidate to heavy quarks. Contrary to what could have been naively anticipated, the PAMELA pbar/p measurements do not challenge dark matter model building, as far as the quark sector is concerned. A quarkophillic species is therefore not forbidden.Owing to these large couplings, one would expect that a new production channel opens up at the LHC, through quark--quark and quark--gluon interactions. Alas, when the PDF of the quark is taken into account, prospects for a copious production fade away.Comment: 7 pages, 2 figures, captions of some figures modified, main conclusion unchange

Effects of the insecticide fipronil in freshwater model organisms and microbial and periphyton communities

Fipronil is a broad-spectrum insecticide whose release in the environment damages many non-target organisms. This study evaluated the toxicity of fipronil at two biological levels using in vivo conditions and environmentally relevant concentrations: the first based on two model organisms (aquatic invertebrate Daphnia magna and the unicellular freshwater alga Chlamydomonas reinhardtii) and a second based on three natural communities (river periphyton and freshwater and soil microbial communities). The physicochemical properties of fipronil make it apparently unstable in the environment, so its behaviour was followed with high performance liquid chromatography (HPLC) under the different test conditions. The most sensitive organism to fipronil was D. magna, with median lethal dose (LC50) values from 0.07 to 0.38 mg/L (immobilisation test). Toxicity was not affected by the media used (MOPS or river water), but it increased with temperature. Fipronil produced effects on the photosynthetic activity of C. reinhardtii at 20 °C in MOPS (EC50 = 2.44 mg/L). The freshwater periphyton presented higher sensitivity to fipronil (photosynthetic yield EC50 of 0.74 mg/L) in MOPS and there was a time-dependent effect (toxicity increased with time). Toxicity was less evident when periphyton and C. reinhardtii tests were performed in river water, where the solubility of fipronil is poor. Finally, the assessment of the metabolic profiles using Biolog EcoPlates showed that bacteria communities were minimally affected by fipronil. The genetic identification of these communities based on 16S rRNA gene sequencing revealed that many of the taxa are specialists in degrading high molecular weight compounds, including pesticides. This work allows us to better understand the impact of fipronil on the environment at different levels of the food chain and in different environmental conditions, a necessary point given its presence in the environment and the complex behaviour of this compound

Growth, age estimation and corroboration of northeast Atlantic chub mackerel (Scomber colias) in northern Iberian waters: a first attempt.

Updated information on growth of Atlantic chub mackerel in several areas of its distribution is required for the first stock assessment. Its growth pattern in Northern Iberian waters (2011-2017) is here analyzed with different approaches: those based on otoliths analyses (direct age estimation-DAE, back-calculation-BC and otolith marginal analyses) and those based on length frequency analyses (Bhattacharya, SLCA and PROJMAT methods). Two main different growth patterns are obtained, a "slow" one based on DAE, BC and LFDA from surveys; and a "fast" one based on Bhattacharya and LFDA from commercial landings. The divergence between both patterns begins to be evident at age 3 and older. Otolith marginal analyses that show an annual periodicity in the formation of the hyaline and opaque edge, the unimodal distribution of the annuli radius and the similarity of the back-calculated mean lengths to those obtained by DAE, support the age estimation criteria used in our analysis. The VBGF growth parameters (L∞=45.34, k=0.28, t0=1.18) obtained by otolith age estimation are available for the upcoming stock assessment process