8 research outputs found

    Sex and reproductive cycle affect lipid and fatty acid profiles of gonads of Arbacia dufresnii (Echinodermata: Echinoidea)

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    Analysis of the lipid composition of gonads allows differentiation between energy and structural lipids, which is important for understanding lipid utilization during gametogenesis. Fatty acids, which are frequently used as biomarkers in trophic ecology studies, are also a useful companion to lipid studies and provide a detailed understanding of a species' reproductive cycle. We examined the influence of sex and the reproductive cycle on the lipid and fatty acid profiles of gonads in the sea urchin Arbacia dufresnii. In a population from Nuevo Gulf, Argentina, we found significant changes in total lipid concentration, lipid profile and fatty acid profile throughout the reproductive cycle. Ovaries and testes containing fully mature gametes differed in total lipid concentration (higher in the ovaries), lipid profile (more energy lipids in ovaries and more structural lipids in testes) and fatty acid profile (differed by sex, not only in the variety of fatty acids present but in the degree of unsaturation). Our results show that differences in lipid and fatty acid profiles caused by sex and gonadal reproductive stage need to be considered when these tools are used as biomarkers in ecological studies.Fil: Zárate, Erica. The University of Auckland; Nueva ZelandaFil: Díaz de Vivar, María Enriqueta Adela. Universidad Nacional de la Patagonia; ArgentinaFil: Avaro, Marisa Gladis. Universidad Nacional de la Patagonia; ArgentinaFil: Epherra, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Sewell, Mary A.. The University of Auckland; Nueva Zeland

    Life cycle assessment (LCA) of newsprint production at an integrated mill

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    Overview of newsprint life cycle -- Critical environmental issues for integrated newsprint mills in Canada -- Overview of life cycle assessment (LCA) methodology -- Synthesis and critical review

    Las acciones lúdicas en los niños del nivel inicial

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    Trabajo académicoEn la presente monografía, haremos un recorrido por conceptos claves relacionados con el juego y sus principales concepciones, para luego detenernos en aquellos relacionados a de las actividades lúdicas y su incidencia en el desarrollo del niño, así como en el tratamiento de las teorías psicológicas, que constituye el eje central en este trabajo. La presente investigación bibliográfica tiene como objetivo principal: Analizar la importancia de las actividades lúdicas escolares en el niño del nivel inicial y, para su realización, se ha considerado como metodología la selección de diversas fuentes bibliográficas fiables que permitieron obtener los conceptos y las teorías pertinentes para esta investigación

    Nicotinic antagonist UFR2709 inhibits nicotine reward and decreases anxiety in zebrafish

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    Zebrafish is becoming a popular animal model in neuropharmacology and drug discovery, mainly due to its ease of handling and low costs involved in maintenance and experimental work. This animal displays a series of complex behaviours that makes it useful for assessing the e ects of psychoactive drugs. Here, adult zebrafish were used for assessment of the anxiolytic and anti-addictive properties of UFR2709, a nicotinic receptor (nAChR) antagonist, using two behavioural paradigms to test for addiction, the novel tank diving test to assess anxiety and the conditioned place preference (CPP). Furthermore, the expression of nAChR subunits 4 and 7 was measured in the zebrafish brain. The results show that UFR2709 exhibits an anxiolytic e ect on zebrafish and blocks the e ect evoked by nicotine on CPP. Moreover, UFR2709 significantly decreased the expression of 4 nicotinic receptor subunit. This indicates that UFR2709 might be a useful drug for the treatment of nicotine addiction.National Agency of Research and Development, Chile 115-0615 117-0662 120-047

    Risk of COVID-19 after natural infection or vaccinationResearch in context

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    Summary: Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health

    NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

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    Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data
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