143 research outputs found
Roles, Functions and Necessary Competences for Teachers’ Assessment in b-Learning Contexts
AbstractHigher Education Institutions are committed to ensure spaces of combined education or b-learning. Associated with this aim, there is a concern about the roles and functions that the teacher performs and how to assess them. This study is located at the intersection of research in educational assessment and b-learning in Higher Education. Under this foresight, this research is developed in a descriptive and propositive manner, adopting a qualitative approach which –through the implementation of grounded theory- encodes and analyzes 105 texts selected to present the characterization of the roles, functions and competences that the teachers must perform at the different stages of the process for developing a course based on b-learning methodology
Hacia un sistema energético sin emisiones de carbono
El calentamiento atmosférico y oceánico -con sus consecuentes alteraciones climáticas- , el envenenamiento del aire, el agua y el suelo por diversos contaminantes, las guerras por el control del petróleo y el gas natural, los derrames de crudo en los océanos, y las enormes fugas en depósitos y embarcaciones que transportan gas natural (que es esencialmente metano, un gas 25 veces peor que el C02 en el efecto invernadero) son consecuencias directas del actual sistema energético basado en combustibles fósiles. El doctor James E. Hansen y otros expertos han hecho notar que el valor seguro para 1a estabilidad climática es cuando mucho de 350 partes por millón (ppm) de C02 en la atmósfera. Actualmente. la concentración de C02 ha rebasado 393 ppm, es decir, estamos en gran riesgo. La masa de la atmósfera es de 5. l x 10 18 kg y cada ppm de C02 corresponde, en términos másicos, a casi 7.75 mil millones de rondadas de este gas. ¡Habría que retirar de la atmósfera una cantidad superior a 333 mil millones de toneladas de C02 equivalente para que la atmósfera recuperara su estabilidad! Sin embargo, se pretende que las emisiones continúen de manera que, si se toman medidas extraordinarias a nivel planetario, se estabilice el C02 atmosférico en no mucho más de 450 ppm. Obviamente, este tipo de metas conducen al desastre. L-t alternativa para salvar la atmósfera es una transición rápida hacia un sistema energético mundial basado en la energía solar y otras fuentes renovables, como el viento, las biomasas y la geotermia, entre otras, y aunado a una deforestación cero con recuperación de bosques y selvas para reducir la concentración de C02 a 350 ppm. La energía solar y las demás fuentes renovables de la misma podrían satisfacer cualquier necesidad energética de las presentes y futuras generaciones si se desarrollan, de manera económica, los sistemas para su aprovechamiento. En este artículo se esboza cómo eliminar las emisiones de C02 empleado tecnologías energéticas de cero emisiones de este óxido. Muchas de estas pueden ser desarrolladas en México, en nuestras universidades públicas, para aprovechar de la mejor manera los recursos renovables con las particularidades con que se presentan en nuestro país
In silico screening and heterologous expression of a Polyethylene Terephthalate hydrolase (PETase)- like enzyme (SM14est) with Polycaprolactone (PCL)-degrading activity, from the marine sponge-derived strain Streptomyces sp. SM14.
Plastics, such as the polyethylene terephthalate (PET), are widely used for various industrial applications, due to their physicochemical properties which are particularly useful in the packaging industry. However, due to improper plastic waste management and difficulties in recycling, post-consumer plastic waste has become a pressing issue for both the environment and for human health. Hence, novel technologies and methods of processing plastic waste are required to address these issues. Enzymatic-assisted hydrolysis of synthetic polymers has been proposed as a potentially more efficient and environment-friendly alternative to the currently employed methods. Recently, a number of PET hydrolases have been described, and in particular a PETase derived from Ideonella sakaiensis 201-F6 (IsPETase), which appears to be the most efficient and substrate-specific bacterial PET hydrolase enzyme discovered to date. In order to further investigate this class of PETase-like enzymes, we employed an in silico-based screening approach on the biotechnologically relevant genus Streptomyces, including terrestrial and marine isolates; in a search for potential PETase homologs. From a total of 52 genomes analyzed, we were able to identify three potential PETase-like enzymes, all of which were derived from marine-sponge associated Streptomyces isolates. A candidate PETase-like gene (SM14est) was identified in Streptomyces sp. SM14. Further in silico characterization of the SM14est protein sequence and its predicted three-dimensional structure were performed and compared to the well-characterized IsPETase. Both the serine hydrolase motif Gly-x1-Ser-x2-Gly and the catalytic triad Ser, Asp, His are conserved in both sequences. Molecular docking experiments indicated that the SM14est enzyme possessed the capacity to bind plastics as substrates. Finally, polyesterase activity was confirmed using a polycaprolactone (PCL) plate clearing assay which is a model substrate for the degradation of plastics; following heterologous expression of SM14est in Escherichia coli, with secretion being facilitated by the native Streptomyces signal peptide. These findings provide further insights into this important class of PETase-like enzymes
Comparative genomics of marine sponge-derived Streptomyces spp. isolates SM17 and SM18 with their closest terrestrial relatives provides novel insights into environmental niche adaptations and secondary metabolite biosynthesis potential
The emergence of antibiotic resistant microorganisms has led to an increased need for the discovery and development of novel antimicrobial compounds. Frequent rediscovery of the same natural products (NPs) continues to decrease the likelihood of the discovery of new compounds from soil bacteria. Thus, efforts have shifted toward investigating microorganisms and their secondary metabolite biosynthesis potential, from diverse niche environments, such as those isolated from marine sponges. Here we investigated at the genomic level two Streptomyces spp. strains, namely SM17 and SM18, isolated from the marine sponge Haliclona simulans, with previously reported antimicrobial activity against clinically relevant pathogens; using single molecule real-time (SMRT) sequencing. We performed a series of comparative genomic analyses on SM17 and SM18 with their closest terrestrial relatives, namely S. albus J1074 and S. pratensis ATCC 33331 respectively; in an effort to provide further insights into potential environmental niche adaptations (ENAs) of marine sponge-associated Streptomyces, and on how these adaptations might be linked to their secondary metabolite biosynthesis potential. Prediction of secondary metabolite biosynthetic gene clusters (smBGCs) indicated that, even though the marine isolates are closely related to their terrestrial counterparts at a genomic level; they potentially produce different compounds. SM17 and SM18 displayed a better ability to grow in high salinity medium when compared to their terrestrial counterparts, and further analysis of their genomes indicated that they possess a pool of 29 potential ENA genes that are absent in S. albus J1074 and S. pratensis ATCC 33331. This ENA gene pool included functional categories of genes that are likely to be related to niche adaptations and which could be grouped based on potential biological functions such as osmotic stress, defense; transcriptional regulation; symbiotic interactions; antimicrobial compound production and resistance; ABC transporters; together with horizontal gene transfer and defense-related features
Energetic metabolic profile of ewes presenting low body condition score induced to subclinical hypocalcemia in early postpartum
The aim of the present study is to assess plasma concentrations of metabolites related to energy balance in ewes showing low body condition score (BCS) induced to subclinical hypocalcemia in early postpartum. Sixteen crossbred ewes (Ideal x Corriedale) presenting BCS <3 were divided in two groups: 1) control group (n = 9), which received no treatment, and 2) hypocalcemia group (n = 7), which was subjected to twelve hours of induced subclinical hypocalcemia through intravenous Na2EDTA infusion six hours postpartum. Ionized calcium levels were monitored and kept between 0.62 and 0.87 mmol/L. All ewes were subjected to daily blood sampling for five days in order to set the postpartum metabolic profile. There was no interaction between day and treatment in total and ionized calcium concentrations (P>0.05), whereas the mean concentrations of these marks after five days were lower in the hypocalcemia group (P<0.05). However, neither the mean group were different at glucose, non-esterified fatty acids, beta-hydroxybutyrate and insulin (P>0.05) level. These results evidence that, despite the subclinical hypocalcemia induction at early postpartum, ewes presenting low body condition do not change the concentrations of energy balance-related metabolites in the following five days
Biomedical engineering in colombia: an undergraduate studies approach
El presente artículo expone el estado de la formación en Ingeniería Biomédica en Colombia a nivel de pregrado.
Se revisaron programas de la Unión Europea y los Estados Unidos. A nivel nacional, se revisaron, bajo la categoría de Ingeniería
Biomédica y Bioingeniería, los planes de estudio de quince instituciones de educación superior a partir de tres fuentes de información:
Páginas Web de Universidades, Sistema de Información de Educación Superior y Observatorio Laboral (Ministerio de Educación
Nacional). Se encontró que la oferta de los programas nacionales de Ingeniería Biomédica y Bioingeniería en su conjunto en la
ciudad de Bogotá D.C. representa el 30% de la totalidad de la oferta en el país, Antioquia (Medellín) representa el 27%, Valle del
Cauca (Cali) el 13% y los demás departamentos representan el 30% restante. Los programas de educación superior en Ingeniería
Biomédica muestran una uniformidad en cuanto a la duración y a las competencias a desarrollar con ligeras diferencias en los
énfasis y los perfiles de egreso. Actualmente existen al menos 528 Ingenieros Biomédicos y Bioingenieros graduados en el país
(0,27% del total de las ingenierías). La tasa de graduados por año, entre 2001 y 2007 es en promedio de 75 Ingenieros Biomédicos
y Bioingenieros. Se puede concluir que a pesar de la oferta de programas activos de Ingeniería Biomédica a nivel nacional, la tasa
de graduados es baja con relación a: la población colombiana que va en aumento, el incremento de personas con discapacidad y
adultos mayores y el número de graduados de otras ingenierías. Se propone la reflexión, sobre el reto que imponen los avances
científicos y tecnológicos mundiales que de alguna manera se convierten en directrices de formación.This academic paper presents the state of Colombia`s undergraduate education in Biomedical Engineering. Programs of
the European Union and of the United States were reviewed. In the national level, fifteen programs of different higher education institutions
were reviewed under the category of Biomedical Engineering and Bioengineering, based on three information sources: University official
Website, Information System on higher education and work observatory of the National Education Ministry. It was found that the total
offer of national undergraduate programs in Biomedical Engineering and Bioengineering in Bogota D.C represents the 30% of the total
offer in the country, Antioquia (Medellín) represents the 27%, Valle del Cauca (Cali) the 13% and the other departments represent the
30% left. The undergraduate programs in Biomedical Engineering show similar standards regarding length, and professional developing
competences with slight differences in the graduation profiles and the emphasis. In the present, there are at least 528 graduated Biomedical
Engineering and bioengineers in the country (0,27% of all engineering graduates). The rate of graduates per year, between 2001 and 2007,
is close to 75 biomedical Engineers and bioengineers. It can be concluded, that despite the offer of active programs in the national level,
the rate of graduates is low in relation to: the Colombian population which is growing, the growth of the number of people with disabilities
and elders, and the number of graduates from other engineering fields. A reflection is proposed, regarding the challenges that worldwide
scientific and technological advances present, which in some measure become formation directives
Effect of immunocastration on behaviour and blood parameters (cortisol and testosterone) of Holstein bulls
To evaluate the effect that immunocastration has on behaviour, testosterone and cortisol levels of feedlot Holstein bulls, 720 intact animals aged between 7 and 8 months, weighing 232±1.19 kg were randomly assigned to two treatments: immunocastration using the Bopriva vaccine and a placebo (360 animals per treatment). The bulls were slaughtered at day 239 of treatment. Animals were vaccinated on days 1, 21, 101, and 181, and on those same days testosterone levels were measured; while cortisol, glucose and creatin kinase measurements were done on day 181 and during exanguination at slaughter. Sexual, aggressive and social behaviours were evaluated and it was found that intact bulls showed a higher average of head butts, mounting, threats, flehmen sign and sniffing (P<0.05), no differences were found for vocalisations, lowering of the head and grooming (P>0.05). Testosterone levels in intact bulls remained at 0.47ng/mL throughout the study, however, by day 181 differences (P<0.05) were observed in immunised bulls, with values of 0.22ng/mL. At slaughter, testosterone levels were 0.21 ± 0.06 ng/mL in immunocastrated bulls and 0.54 ± 0.06 ng/mL in the placebo group. The use of immunocastration with Bopriva has shown to be effective to reduce testosterone, sexual and aggressive behaviours on Holstein bulls
Genome mining coupled with OSMAC-based cultivation reveal differential production of surugamide A by the marine sponge isolate Streptomyces sp. SM17 when compared to its terrestrial relative S. albidoflavus J1074
Much recent interest has arisen in investigating Streptomyces isolates derived from the marine environment in the search for new bioactive compounds, particularly those found in association with marine invertebrates, such as sponges. Among these new compounds recently identified from marine Streptomyces isolates are the octapeptidic surugamides, which have been shown to possess anticancer and antifungal activities. By employing genome mining followed by an one strain many compounds (OSMAC)-based approach, we have identified the previously unreported capability of a marine sponge-derived isolate, namely Streptomyces sp. SM17, to produce surugamide A. Phylogenomics analyses provided novel insights on the distribution and conservation of the surugamides biosynthetic gene cluster (sur BGC) and suggested a closer relatedness between marine-derived sur BGCs than their terrestrially derived counterparts. Subsequent analysis showed differential production of surugamide A when comparing the closely related marine and terrestrial isolates, namely Streptomyces sp. SM17 and Streptomyces albidoflavus J1074. SM17 produced higher levels of surugamide A than S. albidoflavus J1074 under all conditions tested, and in particular producing >13-fold higher levels when grown in YD and 3-fold higher levels in SYP-NaCl medium. In addition, surugamide A production was repressed in TSB and YD medium, suggesting that carbon catabolite repression (CCR) may influence the production of surugamides in these strains
Frecuencia de visitas al departamento de emergencias y hospitalizaciones debido a exacerbaciones de la enfermedad pulmonar obstructiva crónica en pacientes incluidos en dos modelos de atención
Introduction: Exacerbations of chronic obstructive pulmonary disease (COPD) have a huge impact on lung function, quality of life and mortality of patients. Emergency Department visits and hospitalizations due to exacerbations cause a significant economic burden on the health system.Objective: To describe the differences in the number of emergency visits and hospitalizations due to exacerbations of COPD among patients included in two models of care of the same institution.Materials and methods: A historical cohort study in which COPD patients who are users of two models of care were included: COPD integrated care program (CICP) and general consultation of pulmonology (GCP). The first model, unlike the second one, offers additional educational activities, 24/7 telephone service, and priority consultations. The number of emergency visits and hospitalizations due to COPD exacerbations in patients who had completed at least one year of follow-up was evaluated. The multivariable Poisson regression model was used for calculating the incidence rate (IR) and the incidence rate ratio (IRR) with an adjustment for confounding factors.Results: We included 316 COPD patients (166 from the CICP and 150 from the GCP). During the year of follow-up, the CICP patients had 50% fewer emergency visits and hospitalizations than patients from the GCP (IRR=0.50, 95%CI: 0.29-0.87, p=0.014). Conclusions: COPD patients in the CICP had fewer emergency visits and hospitalizations due to exacerbations. Prospective clinical studies are required to confirm the results and to evaluate the factors that contribute to the differences.Introducción. Las exacerbaciones de la enfermedad pulmonar obstructiva crónica (EPOC) tienen un gran impacto en la función pulmonar, la calidad de vida y la mortalidad de los pacientes. Las visitas al Departamento de Emergencias y las hospitalizaciones debido a las exacerbaciones, causan una carga económica importante para el sistema de salud.Objetivo. Describir las diferencias en el número de visitas de emergencia y hospitalizaciones debidas a exacerbaciones de la EPOC, entre los pacientes incluidos en dos modelos de atención de la misma institución. Materiales y métodos. Se trata de un estudio de cohorte histórica en el que se incluyeron pacientes que son usuarios de dos modelos de atención: el programa de atención integrada de la EPOC (CICP) y la consulta general de neumología (PCG). El primer modelo, a diferencia del segundo, ofrece actividades educativas adicionales, servicio telefónico las 24 horas del día y consultas prioritarias. Se evaluó el número de visitas de emergencia y hospitalizaciones debido a exacerbaciones de la EPOC en pacientes que habían completado, al menos, un año de seguimiento. Se utilizó el modelo de regresión multivariable de Poisson para calcular la tasa de incidencia (IR) y la razón de tasas de incidencia (IRR), con un ajuste para factores de confusión. Resultados. Se incluyeron 316 pacientes con EPOC, 166 del CICP y 150 de la PCG. Durante el año de seguimiento, los pacientes en el CICP tuvieron 50 % menos visitas de emergencia y hospitalizaciones que los pacientes en la PCG (IRR=0,50; IC95% 0,29-0,87; p=0,014). Conclusiones. Los pacientes con EPOC en el CICP, tuvieron menos visitas de emergencia y hospitalizaciones debido a las exacerbaciones. Se requieren estudios clínicos prospectivos para confirmar los resultados y evaluar los factores que contribuyen a las diferencias
Payment Systems Report - June of 2019
For the last decade, Banco de la República has provided oversight of the local financial infrastructure as an additional contribution to support the country’s financial stability. This is a function performed by most central banks the world over, because they recognize infrastructure as being an essential component of financial markets. Infrastructure that functions properly helps to maintain and promote financial stability, being that it plays a fundamental role in the financial system and in the economy. In the Colombian case, the oversight of the country’s financial infrastructures began formally a decade ago, when External Resolution 5/2009 was issued and the authority to oversight that infrastructures was given to Banco de la República by its Board of Directors. Since then, the oversight has been formal and systematic. To commemorate ublication of the tenth edition of the Payment Systems Report, which is one of the products of financial infrastructure oversight, a section describing this function is included herein, explaining its need, responsibilities, scope, and activities.
On this occasion, in addition to the traditional section providing figures on the local financial infrastructure and describing its behavior (Section One), we have included several highlights that underscore the more relevant aspects of how infrastructure for clearing and settling financial assets has evolved in the last decade. Special emphasis is afforded to the Colombian Central Counterparty Clearing House (CRCC), marking its ten years of operation. There also is a box describing how the company has increased its supply of products for clearing and settlement, and how, as a result, the open positions of its settlement members have performed likewise. At the same time, its risk management model has evolved structurally in response to regulatory adjustments, compliance with international standards, or decisions taken unilaterally by the CRCC, the idea being to have the necessary resources to mitigate exposure to counterparty and liquidity risk. In this way, the CRCC has become a undamentally important player in the Colombian financial market. Therefore, it is appropriate that the CRCC continue to be monitored by the country’s financial authorities.
Another box included in this report offers an analysis of the advantages and disadvantages of lengthening the cash market settlement period in Colombia, which is another topic of interest. Currently, the clearing and settlement time for a cash transaction in most international markets is two business days (t + 2). In Colombia, nearly all peso/dollar and government and private debt transactions on the spot market are cleared and settled on the same trading day (t + 0). This box analyzes the possible implications of Colombia approximating the international standard.
Retail-value payment systems (understood as operations carried out within the circuit of private individuals and companies), such as the use of payment instruments (cash, debit and credit cards, checks and electronic funds transfers), also must be monitored to identify their availability and the public’s preferences for these instruments and their acceptance by commercial establishments. With that in mind, three surveys have been conducted in the last decade to gauge how the use of payment instruments is perceived. A comparison of the findings of these three measurements is presented in a section of this report, and an analysis of that comparison indicates the use of payment instruments other than cash for daily payments is still low. Although their ownership and use by the general public is increasing, their acceptance by some commercial establishments remains limited.
In keeping with efforts to oversight innovations in payment processes, the report also includes a box that explores the participation of large, global technology companies in the retail-value payment market. The payment services they offer are associated with innovative payment methods, such as “non-contact” or indirect technology, or by means of devices such as mobile phones, the use of debit and credit cards via applications, and channels such as the mobile network, POS terminals, and the Internet. In other words, these innovations are concentrated in the first stage of the payment process, without altering the other stages, such as traditional payment instruments, channels and systems.
Finally, with respect to work in the area of applied research, the fourth section of this report describes how the cryptoasset system operates. It has two fundamental elements. The first is comprised of the agents who participate in the system; namely, cryptoasset users, and the agents who provide them with services. The second includes the digital asset and the underlying technology platform; together they support interaction between the agents in the crypto asset system. As explained in the respective box, the cryptoasset system is not isolated entirely from the financial system, which it pretends do without. In other words, users cannot extract themselves from the traditional financial system as long as cryptoassets have yet to be adopted on a mass scale, which so far assumes there is a connection between both systems.
Juan José Echavarría
Governo
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