Assignments as Influential Factor to Improve the Prediction of Student Performance in Online Courses

Studies on the prediction of student success in distance learning have explored mainly demographics factors and student interactions with the virtual learning environments. However, it is remarkable that a very limited number of studies use information about the assignments submitted by students as influential factor to predict their academic achievement. This paper aims to explore the real importance of assignment information for solving students’ performance prediction in distance learning and evaluate the beneficial effect of including this information. We investigate and compare this factor and its potential from two information representation approaches: the traditional representation based on single instances and a more flexible representation based on Multiple Instance Learning (MIL), focus on handle weakly labeled data. A comparative study is carried out using the Open University Learning Analytics dataset, one of the most important public datasets in education provided by one of the greatest online universities of United Kingdom. The study includes a wide set of different types of machine learning algorithms addressed from the two data representation commented, showing that algorithms using only information about assignments with a representation based on MIL can outperform more than 20% the accuracy with respect to a representation based on single instance learning. Thus, it is concluded that applying an appropriate representation that eliminates the sparseness of data allows to show the relevance of a factor, such as the assignments submitted, not widely used to date to predict students’ academic performance. Moreover, a comparison with previous works on the same dataset and problem shows that predictive models based on MIL using only assignments information obtain competitive results compared to previous studies that include other factors to predict students performance

El Recurso de Casación Civil en el Sistema Judicial Peruano en el bienio 2012 - 2013

La investigación se originó ante la necesidad de determinar, si la Casación Civil cuando declaró improcedentes los Recursos de Casación en el Perú en el Bienio 2012- 2013, cumplió su finalidad, puesto que si se tiene como finalidades del Recurso de Casación Civil, la protección de la norma jurídica, la unificación de la jurisprudencia, esta no puede lograrse si muchos Recursos de Casación Civil al ser declarados improcedentes, ni siquiera serán objeto de estudio o análisis. Frente al problema planteado se formuló la siguiente hipótesis: “La Casación Civil cuando declara improcedentes los Recursos de Casación en el Perú en el Bienio 2012- 2013, no ha cumplido su finalidad, porque en dichos casos no se llega a determinar la observancia correcta de la norma, ni uniformizar los criterios jurisprudenciales”.  La investigación fue dividida en dos fases: teórica y estadística. En la primera fase se hizo un análisis doctrinario, legal y jurisprudencial del tema de estudio.  En la segunda fase, se revisó y se procesó el total de Recursos de Casación Civil, que fueron declarados improcedentes, en el Bienio 2012-2013, registrando las características más relevantes de cada uno de ellos, como lo fueron: Los motivos de improcedencia, normas invocadas, pretensiones, tanto en la Sala Civil Permanente como en el Sala Civil Transitoria de la Corte Suprema de la República del Perú. Para la recolección de los datos se utilizaron las técnicas de la observación documental, y el fichaje, elaborándose diversos instrumentos como: las hojas de registro, fichas y cuadernillos de encuestas. Para el estudio de la información se utilizaron diversos métodos, entre ellos el método analítico, exegético y sistemático. Para la organización de la información y su presentación se emplearon figuras, tablas, y cuadros estadísticos. Los resultados evidenciaron que la Casación Civil cuando declara improcedentes los Recursos de Casación en el Perú en el Bienio 2012- 2013, no ha cumplido su finalidad, porque en dichos casos no se llega a determinar la observancia correcta de la norma, ni uniformiza los criterios jurisprudenciales, porque sustenta sus decisiones en estrictas y literales formalidades que impiden el desarrollo de la doctrina jurisprudencial, el acceso a la tutela judicial efectiva y el cumplimiento de la tercera finalidad de la Casación Civil, que es la finalidad dikelógica, que es la búsqueda  o consecución de justicia, que no se logra

Pneumonia Detection in Chest X-ray Images using Convolutional Neural Networks

Pneumonia is an infectious and deadly disease which strikes over millions of people. Usually, chest X-rays are used by radiotherapist to diagnose pneumonia. In this paper, a Computer- Aided Diagnosis (CAD) system for pneumonia detection in chest X-ray images is proposed. This system is based on Convolutional Neural Networks (CNNs) which are able to classify the image into two classes (pneumonia or normal). Experimental results show that the proposed system obtained an accuracy rate of 98.59%.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Bioaccumulation/bioconcentration of pharmaceutical active compounds in aquatic organisms: Assessment and factors database

There is increasing evidence that the presence of certain pharmaceuticals in the environment leads to biota exposure and constitute a potential risk for ecosystems. Bioaccumulation is an essential focus of risk assessment to evaluate at what degree emerging contaminants are a hazard both to the environment and the individuals that inhabit it. The main goals of the present review are 1) to summarize and describe the research and factors that should be taken into account in the evaluation of bioaccumulation of pharmaceuticals in aquatic organisms; and 2) to provide a database and a critical review of the bioaccumulation/bioconcentration factors (BAF or BCF) of these compounds in organisms of different trophic levels. Most studies fall into one of two categories: laboratory-scale absorption and purification tests or field studies and, to a lesser extent, large-scale, semi-natural system tests. Although in the last 5 years there has been considerable progress in this field, especially in species of fish andmolluscs, research is still limited on other aquatic species like crustaceans or algae. This revision includes >230 bioconcentration factors (BCF) and >530 bioaccumulation factors (BAF), determined for 113 pharmaceuticals. The most commonly studied is the antidepressant group, followed by diclofenac and carbamazepine. There is currently no reported accumulation data on certain compounds, such as anti-cancer drugs. BCFs are highly influenced by experimental factors (notably the exposure level, time or temperature). Field BAFs are superior to laboratory BCFs, highlighting the importance of field studies for reliable assessments and in true environmental conditions. BAF data appears to be organ, species and compound-specific. The potential impact on food web transfer is also considered. Among different aquatic species, lower trophic levels and benthic organisms exhibit relatively higher uptake of these compounds.MCIN/AEI/10.13039/501100011033/ (grant: PID2020-117641RB-I00)Consejería de Economía, Conocimiento, EmpresasUniversidad (Spanish regional Government of Andalucia)European funding from ERDF 2014–2020 program (grants B.RNM.362.UGR20 and P20_00556

Bioaccumulation/bioconcentration of pharmaceutical active compounds in aquatic organisms: Assessment and factors database

There is increasing evidence that the presence of certain pharmaceuticals in the environment leads to biota exposure and constitute a potential risk for ecosystems. Bioaccumulation is an essential focus of risk assessment to evaluate at what degree emerging contaminants are a hazard both to the environment and the individuals that inhabit it. The main goals of the present review are 1) to summarize and describe the research and factors that should be taken into account in the evaluation of bioaccumulation of pharmaceuticals in aquatic organisms; and 2) to provide a database and a critical review of the bioaccumulation/bioconcentration factors (BAF or BCF) of these compounds in organisms of different trophic levels. Most studies fall into one of two categories: laboratory-scale absorption and purification tests or field studies and, to a lesser extent, large-scale, semi-natural system tests. Although in the last 5 years there has been considerable progress in this field, especially in species of fish and molluscs, research is still limited on other aquatic species like crustaceans or algae. This revision includes >230 bioconcentration factors (BCF) and >530 bioaccumulation factors (BAF), determined for 113 pharmaceuticals. The most commonly studied is the antidepressant group, followed by diclofenac and carbamazepine. There is currently no reported accumulation data on certain compounds, such as anti-cancer drugs. BCFs are highly influenced by experimental factors (notably the exposure level, time or temperature). Field BAFs are superior to laboratory BCFs, highlighting the importance of field studies for reliable assessments and in true environmental conditions. BAF data appears to be organ, species and compound-specific. The potential impact on food web transfer is also considered. Among different aquatic species, lower trophic levels and benthic organisms exhibit relatively higher uptake of these compounds

In-vitro evaluation of the adhesion to polypropylene sutures of non-pigmented, rapidly growing mycobacteria

AbstractThe ability of non-pigmented, rapidly growing mycobacteria (NPRGM) to attach to polypropylene sutures was evaluated using an in-vitro assay. Thirty clinical isolates and five culture collection strains of NPRGM, together with Staphylococcus epidermidis ATCC 35983, were tested. Mycobacterium fortuitum and Mycobacterium chelonae showed the highest attachment ability, which differed significantly from the results obtained with Mycobacterium peregrinum. According to these results, NPRGM are able to attach to polypropylene sutures, and the species implicated most frequently in human infection showed increased levels of attachment in comparison with the other mycobacteria studied

An Overview of Analytical Methods to Determine Pharmaceutical Active Compounds in Aquatic Organisms

There is increasing scientific evidence that some pharmaceuticals are present in the marine ecosystems at concentrations that may cause adverse effects on the organisms that inhabit them. At present, there is still very little scientific literature on the (bio)accumulation of these compounds in different species, let alone on the relationship between the presence of these compounds and the adverse effects they produce. However, attempts have been made to optimize and validate analytical methods for the determination of residues of pharmaceuticals in marine biota by studying the stages of sample treatment, sample clean-up and subsequent analysis. The proposed bibliographic review includes a summary of the most commonly techniques, and its analytical features, proposed to determine pharmaceutical compounds in aquatic organisms at different levels of the trophic chain in the last 10 years.Ministerio de Ciencia e Innovación PID2020-117641RB-I00Junta de Andalucía B.RNM.362.UGR20, P20_0055

Compuestos perfluorados en equinodermos marinos: metodología analítica para su determinación y monitorización

Los disruptores endocrinos están en el punto de mira de estudios ambientales y ecotoxicológicos. Entre ellos destacan los compuestos perfluorados, tanto por su amplio uso industrial y doméstico como por su elevada actividad estrogénica. Se descargan al medio ambiente a través de efluentes industriales y de estaciones depuradoras de aguas residuales afectando principalmente a la biota donde pueden bioacumularse. En este trabajo se propone un método analítico para la determinación de seis compuestos perfluorados en organismos marinos (Holothuria tubulosa) y se lleva a cabo un programa de monitorización ambiental para el seguimiento de estos compuestos. El análisis de las muestras se realizó mediante extracción con disolventes, limpieza del extracto por extracción en fase sólida dispersiva y posterior determinación mediante cromatografía de líquidos con detección de espectrometría de masas en tándem. Las recuperaciones obtenidas se situaron en el rango de 84 a 101 % y límites de cuantificación inferior a 0,03 ng/g (peso seco (ps)). Todas las muestras dieron positivas en el análisis de los contaminantes con concentraciones entre 667 ng/g (ps) para el ácido perfluorooctanoico y 0,81 ng/g (ps) para el ácido perfluoropentanoico. Además, se observaron concentraciones más elevadas para los compuestos perfluorados de mayor cadena fluorocarbonada.In recent years endocrine disruptors have come into the spotlight of environmental and ecotoxicological studies. Among them, perfluorinated compounds stand out, both, for their wide industrial and domestic use and for their elevated estrogenic activity, showing adverse effects at trace level. They are released into the environment through industrial waste and wastewater discharges affecting to marine organisms, where they can accumulate. To contribute to this goal, this work proposes an analytical method for the simultaneous determination of six perfluorinated compounds in marine organisms (Holothuria tubulosa) and an environmental monitoring program is carried out in these organisms. The sample treatment involve steps of solvent extraction and clean-up of the extracts with dispersive sorbents prior to liquid chromatography–tandem mass spectrometry analysis. Recoveries between 84 and 101 %, precision (RSD < 9 %) and limits of quantification below 0.03 ng/g dry weight (d.w.) were achieved. All tested samples were positive in the analysis of contaminants with concentrations between 667 ng/g (dw) for perflorooctanoic acid (PFOA) and 0.81 ng/g (dw) for perfloropentanoic acid (PFPeA). In general, perfluorinated compounds of larger fluorocarbonated chain were quantified at higher concentration levels than those of shorter one.Plan Propio de la Universidad de Sevilla Proyecto: 2017/0000096

Solid-State Culture for Lignocellulases Production

Aspergillus sp. and Trametes versicolor solid-state monocultures produced high titers of xylanases and laccases activities (4617 ± 38 and 2759 ± 30 U/gsubstrate, respectively). Fungal biomass was quantified by estimating the ergosterol content of the mycelium, and by a simple material balance the corresponding residual substrate was obtained. Fungal growth and substrate consumption rates showed different behavior for these monocultures (μ = 0.03 and 0.11 h−1; rs = − 0.04 and − 0.0006 gsubstrate/h, respectively). In this case, xylanases production was directly linked to the growth, while laccases were produced during both growth and maintenance phases. Besides xylanases (42% of total Aspergillus enzyme), high titers of cellulases (15%), amylases (34%), and invertases (9%), as well as lignin and manganese peroxidases (10 and 24% of the total Trametes enzyme), were produced on the corresponding monocultures. When both fungi were used in a coculture mode, xylanases and laccases production decreased (around 85 and 70%), and the proportion of the hydrolases and oxidases changed. This suggested the need for most careful coculture design, in order to produce both enzymatic activities simultaneously even though the enzymatic extracts obtained by mono- or cocultures can be applied in several bioprocesses