77 research outputs found

    Removal of Heavy Metals Using Adsorption Processes Subject to an External Magnetic Field

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    Adsorption is a broadly used process for the removal of heavy metals and the world trend is directed to the application of new technologies to intensify existing processes. The properties of the magnetic field (intensity and arrangement) and the intrinsic magnetic properties of the adsorbent and the adsorbate are decisive for satisfactory results. The intensity of the magnetic field is important, because this implies that the greater number of spins present will align with the magnetic field according to the magnetic nature present, allowing the mobility of the adsorbate and generating heterogeneity on the surface of the adsorbent. Similarly, the arrangement of the magnetic field will determine the direction of the magnetic field lines. The application of a magnetic field as an alternative for the intensification of the adsorption process based on the consideration that the magnetic field is safe, environmentally friendly and economic

    Clase espejo como estrategia de enseñanza en Matemáticas Financieras: Un caso de estudio.

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    El caso de estudio expone como objetivo resolver un planteamiento de preguntas acerca de la estrategia didáctica denominada clase espejo, a través de una metodología que delimita un alcance descriptivo y un enfoque mixto. Se diseña un instrumento de recolección de datos compuesto de 33 ítems se emplea software estadístico IBM-SPSS, la muestra, de tipo no probabilístico es de 67 estudiantes de la asignatura Matemáticas financieras dentro de dos programas de estudios de nivel superior de dos instituciones: FACPYA y la Fundación Universitaria Konrad Lorenz. Se presenta un análisis estadístico de los resultados por medio de tablas y gráficos. El instrumento que se utilizó mide factores de motivación: atención, relevancia, confianza y satisfacción. Se obtuvieron resultados con valores muy altos. Los estudiantes señalan que las clases espejo son atractivas y su aprendizaje sencillo. También, muestran su interés por volver a vivir la experiencia en un futuro. Destacan la relevancia y pertinencia de los contenidos de la clase espejo; refieren comentarios positivos de la actividad desarrollada, dejando claro su agradecimiento por este tipo de experiencias. Al evaluar la participación de los maestros y compañeros sugieren un juicio de valor positivo. Se identificaron áreas de oportunidad

    Capacitación laboral en herramientas digitales

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    Los cambios tecnológicos han originado que las personas se capaciten y realicen de forma diferente su trabajo adoptando las nuevas tecnologías, sin embargo, la capacitación no solo concierne al trabajador sino también a los empleadores e instituciones educativas o quienes se encargan de capacitar, todos ellos tienen la obligación de cubrir los perfiles profesionales que demande el mercado laboral. El estudio tuvo como objetivo determinar si los estudiantes de maestría de una universidad pública del noreste de México se están capacitando o no en herramientas digitales. La metodología se definió como alcance de tipo exploratorio descriptivo, se creó y aplicó una encuesta integrada por 16 preguntas cerradas y 3 abiertas. La muestra fue no probabilística integrada por 550 estudiantes. Los resultados muestran una disminución de capacitación del 24.2% durante el año 2020 respecto al 2019 y esto no es debido a un problema de desempleo originado por la pandemia Covid-19, además se identifica que el 41.5% presentan una capacitación o ninguna al año. El porcentaje más alto de capacitación se da en las herramientas básicas de Microsoft Office con un 30% (Word, Excel y PowerPoint), seguida de los paquetes especializados con un 28.2%, tales como, SPSS, Contpaqi, Aspel SAE, ERP SAP, Photoshop, entre otros. Es importante que universidades, corporaciones y gobiernos generen una alianza a fin de aumentar significativamente el porcentaje de capacitación a fin de satisfacer las necesidades del mercado laboral, así como analizar el costo-beneficio que se puede dar de una capacitación presencial a una en línea

    Nivel de satisfacción mostrado en la interacción entre estudiantes de nivel superior y la plataforma Schoology en un curso de matemáticas financieras de modalidad presencial

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    In the present article describes the satisfaction level forupper level students when interacting with the Schoologyplatform in a fase to face class of financial mathematics.The sample is not probabilistic or directed, the study presented a quantitative, exploratory-descriptive approach.The CUSAUF questionnaire was used as an instrument,adapted to the needs of the research with five dimensions,which revealed a reliability and internal consistency ofα = 0.969. To show the relationship between items, thePearson correlation coefficient was calculated. The elements that stood out in the results are the role of the teacher as a facilitator, the quality of the work materials,the communication and feedback of activities in the platform. It was observed that students are willing to use thistool in other learning units.En el presente artículo se describió el grado de satisfacción de estudiantes de nivel superior al interactuar conla plataforma Schoology en una clase presencial de matemáticas financieras. La muestra es no probabilísticao dirigida, el estudio presento un enfoque cuantitativo,exploratorio-descriptivo. Se utilizó como instrumento elcuestionario del CUSAUF, adaptado a las necesidadesde la investigación con cinco dimensiones, el cual reveló una fiabilidad y consistencia interna de α=0.969. Paramostrar la relación entre ítems, se calculó el coeficientede correlación de Pearson. Los elementos que destacaronen los resultados son el rol del docente como facilitador,la calidad de los materiales de trabajo, la comunicación yretroalimentación de actividades en la plataforma. Se observó que los estudiantes están dispuestos a utilizar estaherramienta en otras unidades de aprendizaje

    Heterosis y aptitud combinatoria para producción y calidad de forraje en seis poblaciones de maíz

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    Six corn populations drawn from outstanding forage quality germplasm, and 15 of their direct crosses were assessed in four sites located between 1,117 and 1,932 m asl. The purpose of the present study was to determine general and specific combining ability and mid parent heterosis for whole plant dry matter (TDM), ear dry matter (EDM), stover dry matter (SDM), in vitro dry matter digestibility (IVDMD), neutral detergent fiber content (NDF) and crude protein (CP). Populations showed significant differences for all dry matter yield characteristics, but not for forage quality, while crosses showed differences for EDM and IVDMD. General combining ability effects (GCA) were high and significant only for TDM, while specific combining ability effects (SCA) were significant for IVDMD. Population P3 had the highest GCA for TDM (0.66 t ha-1) and P5F for EDM (0.49 t ha-1). Early cross P1*P2 had the highest heterosis for TDM (17.6 %) and highly significant SCA effects for both TDM and IVDMD (1.48 t ha-1 and 22.6 g kg-1, respectively), while crosses P2*P5F, P1*P4 and P1*P6F had high mid parent heterosis for EDM, with values ranging from 18.6 % to 26.2 %. None of the crosses showed mid parent heterosis for forage traits of importance.Seis poblaciones de maíz derivadas de fuentes de germoplasma sobresalientes por sus cualidades forrajeras y sus 15 cruzas directas se evaluaron en cuatro localidades entre 1,117 y 1,932 m sobre el nivel del mar. El objetivo fue determinar la aptitud combinatoria general y específica, y la heterosis media para variables de producción: materia seca total (MST), de elote (MSEL) y de rastrojo (MSRAS) y variables de calidad del forraje: digestibilidad in vitro de la materia seca (DIVMS), contenido de fibra detergente neutro (FDN) y proteína cruda (PC). Las poblaciones difirieron significativamente en las tres variables de producción, pero no en calidad forrajera, en cambio las cruzas difirieron en producción de MSEL y en DIVMS. Los efectos de aptitud combinatoria general (ACG) fueron significativos sólo para MST y MSEL, mientras que los efectos de aptitud combinatoria específica (ACE), lo fueron adicionalmente para DIVMS. La población P3 tuvo la mayor ACG para MST (0.66 t ha-1), y la población P5F para MSEL (0.49 t ha-1). La cruza precoz P1xP2 presentó la heterosis media más alta para MST con 17.6 % y efectos positivos y significativos de ACE para MST y DIVMS con valores de 1.48 t ha-1 y 22.6 g kg-1. En cambio, las cruzas P2xP5F, P1xP4 y P1xP6F tuvieron los valores de heterosis más altos para MSEL con valores de 18.1 a 26.2 %. Ninguna cruza tuvo heterosis media importante para caracteres de calidad de forraje

    Transcriptional analysis reveals the metabolic state of Burkholderia zhejiangensis CEIB S4-3 during methyl parathion degradation

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    Burkholderia zhejiangensis CEIB S4-3 has the ability to degrade methyl parathion (MP) and its main hydrolysis byproduct p-nitrophenol (PNP). According to genomic data, several genes related with metabolism of MP and PNP were identified in this strain. However, the metabolic state of the strain during the MP degradation has not been evaluated. In the present study, we analyzed gene expression changes during MP hydrolysis and PNP degradation through a transcriptomic approach. The transcriptional analysis revealed differential changes in the expression of genes involved in important cellular processes, such as energy production and conversion, transcription, amino acid transport and metabolism, translation, ribosomal structure and biogenesis, among others. Transcriptomic data also exhibited the overexpression of both PNP-catabolic gene clusters (pnpABA′E1E2FDC and pnpE1E2FDC) present in the strain. We found and validated by quantitative reverse transcription polymerase chain reaction the expression of the methyl parathion degrading gene, as well as the genes responsible for PNP degradation contained in two clusters. This proves the MP degradation pathway by the strain tested in this work. The exposure to PNP activates, in the first instance, the expression of the transcriptional regulators multiple antibiotic resistance regulator and Isocitrate Lyase Regulator (IclR), which are important in the regulation of genes from aromatic compound catabolism, as well as the expression of genes that encode transporters, permeases, efflux pumps, and porins related to the resistance to multidrugs and other xenobiotics. In the presence of the pesticide, 997 differentially expressed genes grouped in 104 metabolic pathways were observed. This report is the first to describe the transcriptomic analysis of a strain of B. zhejiangensis during the biodegradation of PNP

    Lo glocal y el turismo. Nuevos paradigmas de interpretación.

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    El estudio del turismo se realiza desde múltiples escalas y enfoques, este libro aborda muchos temas que es necesario discutir desde diversas perspectivas; es el caso de la reflexión sobre la propia disciplina y sus conceptos, así como los asuntos específicos referidos al impacto territorial, los tipos de turismo, las cuestiones ambientales, el tema de la pobreza, la competitividad, las políticas públicas, el papel de las universidades, las áreas naturales protegidas, la sustentabilidad, la cultura, el desarrollo, la seguridad, todos temas centrales documentados y expuestos con originalidad y dominio del asunto. Lo multiescalar es básico para la comprensión del sistema turístico, sistema formado de procesos globales, regionales y locales. El eje de discusión del libro es lo glocal, esa interacción entre lo nacional y local con lo global

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

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    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions

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    Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41–6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain.Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000–2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively.Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p &lt; 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2–79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999–2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin.Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics
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