45 research outputs found

    Escribir papers bajo el régimen del management académico: Cuerpo, afectos y estrategias

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    Indexación: Scopus.Chile is a landmark case in opening up higher education to the free market and in the reformulation of the logics that regulate scientific production in universities. This translates into a management system for academic staff oriented by productivity bonuses associated with high-impact publications, by the distribution of research funds conditional on the productivity of researchers and by the rank of academic tasks. In this article, we present the results of a study that sought to explore and understand how highly productive social science academics describe scientific writing from everyday labor practice framed in new regulations of scientific production. Through the analysis of 20 interviews, we propose 3 categories: affectivity, fragility and strategy. These give an account of everyday aspects, as well as tensions and conflicts present in the process of scientific writing.https://atheneadigital.net/article/view/v20-1-fardela-carriel-lazcano-et-a

    Fixação de fósforo por um latossolo vermelho escuro-orto

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    This paper deals with an experiment carried out in pots with the aim of studying the fixation of P in a Dark Red Latosol, from the Municipality of Piracicaba, State of Sao Paulo, Brazil. The main conclusions were as follows: a) about 90% of the fixed P remained soluble in 0,05N H2SO4 solution; b) Fe and Al contributed to increase the quantities of fixed P; c) the pre-treatment of the soil with Ca(H2PO4)2. H2O decreased its capacity for fixing P.Este trabalho relata os resultados de um ensaio realizado com o objetivo de estudar a fixação de P por um Latossolo Vermelho Escuro-Orto, serie Iracema, de Piracicaba, Estado de São Paulo. O ensaio foi realizado em vasos de plástico, cada um recebendo 500 g de terra e os tratamentos, correspondentes a 0, 100, 200, 400, 600 e 1.200 kg/ha de P2O5 na forma de Ca (H2PO4)2. H2O. Houve 4 repetições de cada tratamento. Seguiu-se um período de incubação de 3 semanas, durante o qual as parcelas permaneceram umidecidas, entre 40 e 70% do poder de retenção de umidade. Depois foram feitos trabalhos necessários do que se concluiu que: a) grande proporção do P fixado permaneceu solúvel em H2SO4 0,05 N; b) o Fe e o Al foram importantes na fixação do P; c) o pré-tratamento do solo com Ca (H2P0(4))2· H2O reduziu-lhe a capacidade de fixação de fosfato

    Effect of particle concentration on the microstructural and macromechanical properties of biocompatible magnetic hydrogels

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    We analyze the effect of nanoparticle concentration on the physical properties of magnetic hydrogels consisting of polymer networks of the human fibrin biopolymer with embedded magnetic particles, swollen by a water-based solution. We prepared these magnetic hydrogels by polymerization of mixtures consisting mainly of human plasma and magnetic nanoparticles with OH- functionalization. Microscopic observations revealed that magnetic hydrogels presented some cluster-like knots that were connected by several fibrin threads. By contrast, nonmagnetic hydrogels presented a homogeneous net-like structure with only individual connections between pairs of fibers. The rheological analysis demonstrated that the rigidity modulus, as well as the viscoelastic moduli, increased quadratically with nanoparticle content following a square-like function. Furthermore, we found that time for gel point was shorter in the presence of magnetic nanoparticles. Thus, we can conclude that nanoparticles favor the cross-linking process, serving as nucleation sites for the attachment of the fibrin polymer. Attraction between the positive groups of the fibrinogen, from which the fibrin is polymerized, and the negative OH- groups of the magnetic particle surface qualitatively justifies the positive role of the nanoparticles in the enhancement of the mechanical properties of the magnetic hydrogels. Indeed, we developed a theoretical model that semiquantitatively explains the experimental results by assuming the indirect attraction of the fibrinogen through the attached nanoparticles. Due to this attraction the monomers condense into nuclei of the dense phase and by the end of the polymerization process the nuclei (knots) of the dense phase cross-link the fibrin threads, which enhances their mechanical properties. This journal is © The Royal Society of Chemistry 2017

    Conceptions of learning factors in postgraduate health sciences master students: a comparative study with nonhealth science students and between genders

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    Background: The students’ conceptions of learning in postgraduate health science master studies are poorly understood. The aim of this study was to compare the factors influencing conceptions of learning in health sciences and non-health sciences students enrolled in postgraduate master programs in order to obtain information that may be useful for students and for future postgraduate programs. Methods: A modified version of the Learning Inventory Conception Questionnaire (COLI) was used to compare students’ conception learning factors in 131 students at the beginning of their postgraduate studies in health sciences, experimental sciences, arts and humanities and social sciences. Results: The present study demonstrates that a set of factors may influence conception of learning of health sciences postgraduate students, with learning as gaining information, remembering, using, and understanding information, awareness of duty and social commitment being the most relevant. For these students, learning as a personal change, a process not bound by time or place or even as acquisition of professional competences, are less relevant. According to our results, this profile is not affected by gender differences. Conclusions: Our results show that the overall conceptions of learning differ among students of health sciences and non-health sciences (experimental sciences, arts and humanities and social sciences) master postgraduate programs. These finding are potentially useful to foster the learning process of HS students, because if they are metacognitively aware of their own conception or learning, they will be much better equipped to self-regulate their learning behavior in a postgraduate master program in health sciences.Supported by CTS-115 (Tissue Engineering Group of the University of Granada). The funding body did not took part in the design of the study and collection, analysis and interpretation of data and in writing the manuscript

    Anti-HIV-1 Activity of a New Scorpion Venom Peptide Derivative Kn2-7

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    For over 30 years, HIV/AIDS has wreaked havoc in the world. In the absence of an effective vaccine for HIV, development of new anti-HIV agents is urgently needed. We previously identified the antiviral activities of the scorpion-venom-peptide-derived mucroporin-M1 for three RNA viruses (measles viruses, SARS-CoV, and H5N1). In this investigation, a panel of scorpion venom peptides and their derivatives were designed and chosen for assessment of their anti-HIV activities. A new scorpion venom peptide derivative Kn2-7 was identified as the most potent anti-HIV-1 peptide by screening assays with an EC50 value of 2.76 µg/ml (1.65 µM) and showed low cytotoxicity to host cells with a selective index (SI) of 13.93. Kn2-7 could inhibit all members of a standard reference panel of HIV-1 subtype B pseudotyped virus (PV) with CCR5-tropic and CXCR4-tropic NL4-3 PV strain. Furthermore, it also inhibited a CXCR4-tropic replication-competent strain of HIV-1 subtype B virus. Binding assay of Kn2-7 to HIV-1 PV by Octet Red system suggested the anti-HIV-1 activity was correlated with a direct interaction between Kn2-7 and HIV-1 envelope. These results demonstrated that peptide Kn2-7 could inhibit HIV-1 by direct interaction with viral particle and may become a promising candidate compound for further development of microbicide against HIV-1

    Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)

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    Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; P = 0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, P = 0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic

    Telecontrol de pesaje y ordeño mecánico de ganado vacuno

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    Este proyecto presenta el prototipo de un sistema de telecontrol de pesaje y ordeño mecánico de ganado vacuno. Para la implementación se usa software y hardware libre de fácil acceso, se utilizan sensores, celdas de carga. El primero, a través de cálculos matemáticos nos permite conocer el peso del balanceado que se le proporciona a la vaca después de que ha culminado la etapa de ordeño. Para el monitoreo del estado y valores en tiempo real de las variables del sistema de telecontrol se implementa un servidor web.GuayaquilIngeniero en Telemátic
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