5,225 research outputs found
Seasonal dynamic factor analysis and bootstrap inference : application to electricity market forecasting
Year-ahead forecasting of electricity prices is an important issue in the current context of electricity markets. Nevertheless, only one-day-ahead forecasting is commonly tackled up in previous published works. Moreover, methodology developed for the short-term does not work properly for long-term forecasting. In this paper we provide a seasonal extension of the Non-Stationary Dynamic Factor Analysis, to deal with the interesting problem (both from the economic and engineering point of view) of long term forecasting of electricity prices. Seasonal Dynamic Factor Analysis (SeaDFA) allows to deal with dimensionality reduction in vectors of time series, in such a way that extracts common and specific components. Furthermore, common factors are able to capture not only regular dynamics (stationary or not) but also seasonal one, by means of common factors following a multiplicative seasonal VARIMA(p,d,q)×(P,D,Q)s model. Besides, a bootstrap procedure is proposed to be able to make inference on all the parameters involved in the model. A bootstrap scheme developed for forecasting includes uncertainty due to parameter estimation, allowing to enhance the coverage of forecast confidence intervals. Concerning the innovative and challenging application provided, bootstrap procedure developed allows to calculate not only point forecasts but also forecasting intervals for electricity prices.Dynamic factor analysis, Bootstrap, Forecasting, Confidence intervals
Soft Skills: A Comparative Analysis Between Online and Classroom Teaching
Currently the Spanish universities are making a great effort to effectively incorporate the development and assessment of generic skills in their training programs. Information and communications technologies (ICT) offer a wide range of possibilities but create uncertainty among teachers about the process and results. It is considered of interest to conduct a study to analyze the extent to which social skills like commitment, communication and teamwork are acquired by students and teachers. It seeks to ascertain the influence of the learning context, online or classroom training, in the development of these personal skills among the participants in the sample. For this study two universities have been chosen, Universidad a Distancia de Madrid (UDIMA) offering online training environment, and Universidad Politécnica de Madrid (UPM) with classroom training modality. A total of 257 individuals, 230 students and 27 teachers have answered the survey called Evalsoft. This instrument was designed in the project with the same name by a research team from Universidad Complutense of Madrid (UCM). Some interesting conclusions can be highlighted: it is in the online context where there are higher levels of commitment and teamwork than in the classroom modality; teachers have higher social skills that students and these improve with age. Sex and the training program appear to influence these social skills
Assessing Creativity In Engineering Students: A Comparative Between Degrees and Sudents In First And Last Year
An online open access test (CREAX self-assessment) has been used in this work so that students from degrees in engineering in the Universidad Polite¿cnica of Madrid (UPM) could self-assess their creative competence after several classroom activities. Different groups from the first year course have been statistically compared using data from their assessment. These first year students had different professors in the subject ?Technical Drawing? and belonged to several degrees in the UPM. They were as well compared regarding sex and a group of first year students was also compared to another last year group of the degree so as to observe possible differences in the achievement of this competence. Only one difference was detected concerning sex in one of the degrees. Among degrees, the higher marks obtained by students who had done specific exercises for the development of creativity in class is highlighted. Finally, a significantly high mark was observed in students during their last year of degree with respect to first year students. The tool CREAX has become very useful in the assessment of this competence in the UPM degrees in which it has been implemented
Estudio cinético y mecanismos de reacciones en el proceso de depósito de aleaciones ternarias de Ni-P-Mo
Un depósito de Ni-P-Mo vía química genera un recubrimiento ingenieril empleado por su buena resistencia al desgaste y a la corrosión Los recubrimientos químicos Ni-P-Mo se obtienen por depósito auto catalítica empleando una solución de composición específica, en la que el sustrato cataliza la reacción. El objetivo de este trabajo es determinar la cinética de la reacción de depósito de recubrimientos autocatalíticos Ni-P-Mo de un baño de composición específica, a través de la determinación del consumo en reactivos, el incremento en peso del sustrato recubierto, el espesor y la microdureza del recubrimiento. Se encontró una velocidad media para el depósito de 1.61 mg.min-1cm-2, pero ésta es diferente para cada elemento. Durante la depósito, el factor determinante en la velocidad de depositación es el Mo debido a que (1) su depósito se inhibe por la presencia de fósforo en la solución que se codeposita con el níquel y (2) incrementos en la concentración de molibdato en la solución la hacen inestable. Los resultados obtenidos permiten proponer el mecanismo de codepósito Ni-P-Mo, a través del planteamiento de las reacciones que tienen lugar durante el proceso de depositación
Process simulation and economic feasibility assessment of the methanol production via tri-reforming using experimental kinetic equations
The purpose of this paper is to assess via techno-economic metrics the feasibility of a tri-reforming coupled methanol process. The simulation of the tri-reforming reactor considered empiric kinetic equations, developed by our group in previous studies. The flue gas coming from the furnace that provides the energy required by the reforming reactor was also used as feed, in order to reduce the CO2 emissions. A sensitivity analysis was carried out to determine the influence of the feed composition and temperature in the tri-reforming process results, studying H2O/CH4 and O2/CH4 ratios (0.5–1.5 and 0.35–0.40, respectively), and varying the temperature between 850 and 1050 °C. The methanol plant was also simulated, and an economical study was carried out to know if the proposed process would be economically feasible. The most relevant economic parameters (including the Net Present Value, the Internal Rate of Return, the Payback Period and the break-even) were calculated, showing a quite robust process from an economical point of view.El propósito de este documento es evaluar a través de métricas tecnoeconómicas la viabilidad de un proceso de metanol acoplado de triple reforma. La simulación del reactor de tri-reformado consideró ecuaciones cinéticas empíricas, desarrolladas por nuestro grupo en estudios previos. También se utilizó como alimentación el gas de combustión procedente del horno que proporciona la energía requerida por el reactor de reformado, con el fin de reducir las emisiones de CO 2 . Se realizó un análisis de sensibilidad para determinar la influencia de la composición y temperatura de la alimentación en los resultados del proceso de tri-reformado, estudiando H 2 O/CH 4 y O 2 /CH 4proporciones (0.5-1.5 y 0.35-0.40, respectivamente), y variando la temperatura entre 850 y 1050 °C. También se simuló la planta de metanol y se realizó un estudio económico para saber si el proceso propuesto sería económicamente factible. Se calcularon los parámetros económicos más relevantes (incluyendo el Valor Presente Neto, la Tasa Interna de Retorno, el Periodo de Recuperación y el punto de equilibrio), mostrando un proceso bastante robusto desde el punto de vista económico
Study cases methodology in process dynamic and industrial plants control subject
Dynamic simulation has been incorporated into Chemical Engineering Master
at the University of Castilla‐La Mancha as a teaching tool together with
working cases. Concretely, this study presents the activities, evaluating criteria
and a set of case of studies performed by master students in the process dynamic and industrial plants control course. It is described in detail, the Aspen
HYSYS® simulations carried out to study the influence of main tuning parameters of proportional, integral, and derivative controllers (gain, integral time,
and derivative time) and other relevant parameters such dead‐time, amplitude,
or period of sine wave disturbances. The dynamic simulation helps the students to understand the previously mentioned concepts, analyzing their effect
in the realistic behavior and control of simple processes. Finally, anonymous
online surveys were conducted to evaluate the effectiveness of the proposed
training activities and methodology. Students felt that Aspen HYSYS enhances
the control theory understanding from a chemical engineering perceptive,
eliminating the tediousness and time‐consuming aspect of process calculation.
Thus, this learning methodology promotes a successful achievement of
learning outcomesLa simulación dinámica se ha incorporado al Máster de Ingeniería Química
en la Universidad de Castilla-La Mancha como herramienta docente junto con
casos de trabajo. Concretamente, este estudio presenta las actividades, los criterios de evaluación
y un conjunto de casos de estudio realizados por los alumnos del máster en la asignatura de dinámica de procesos y control de plantas industriales. Se describe en detalle, las simulaciones Aspen
HYSYS® realizadas para estudiar la influencia de los principales parámetros de sintonía de los controladores proporcional, integral y derivativo (ganancia, tiempo integral
y tiempo de derivación) y otros parámetros relevantes como el tiempo muerto, la amplitud
o el periodo de las perturbaciones sinusoidales. La simulación dinámica ayuda a los estudiantes a comprender los conceptos mencionados anteriormente, analizando su efecto
en el comportamiento realista y el control de procesos sencillos. Por último, se realizaron encuestas anónimas
encuestas anónimas en línea para evaluar la eficacia de las actividades
actividades de formación y metodología propuestas. Los estudiantes consideraron que Aspen HYSYS mejora
la comprensión de la teoría de control desde la perspectiva de la ingeniería química
eliminando el aspecto tedioso y lento del cálculo de procesos.
Por lo tanto, esta metodología de aprendizaje favorece la consecución de
resultados del aprendizaj
Activation of Serine One-Carbon Metabolism by Calcineurin A beta 1 Reduces Myocardial Hypertrophy and Improves Ventricular Function
BACKGROUND In response to pressure overload, the heart develops ventricular hypertrophy that progressively decompensates and leads to heart failure. This pathological hypertrophy is mediated, among others, by the phosphatase calcineurin and is characterized by metabolic changes that impair energy production by mitochondria. OBJECTIVES The authors aimed to determine the role of the calcineurin splicing variant CnA beta 1 in the context of cardiac hypertrophy and its mechanism of action. METHODS Transgenic mice overexpressing CnAb1 specifically in cardiomyocytes and mice lacking the unique C-terminal domain in CnA beta 1 (CnA beta 1(Delta i12) mice) were used. Pressure overload hypertrophy was induced by transaortic constriction. Cardiac function was measured by echocardiography. Mice were characterized using various molecular analyses. RESULTS In contrast to other calcineurin isoforms, the authors show here that cardiac-specific overexpression of CnA beta 1 in transgenic mice reduces cardiac hypertrophy and improves cardiac function. This effect is mediated by activation of serine and one-carbon metabolism, and the production of antioxidant mediators that prevent mitochondrial protein oxidation and preserve ATP production. The induction of enzymes involved in this metabolic pathway by CnAb1 is dependent on mTOR activity. Inhibition of serine and one-carbon metabolism blocks the beneficial effects of CnA beta 1. CnA beta 1(Delta i12) mice show increased cardiac hypertrophy and declined contractility. CONCLUSIONS The metabolic reprogramming induced by CnAb1 redefines the role of calcineurin in the heart and shows for the first time that activation of the serine and one-carbon pathway has beneficial effects on cardiac hypertrophy and function, paving the way for new therapeutic approaches. (J Am Coll Cardiol 2018; 71: 654-67) (C) 2018 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation. This is an open access article under the CC BY-NC-ND license (http://creativecommons. org/licenses/by-nc-nd/4.0/).This work was supported by grants from the European Union (CardioNeT-ITN-289600 and CardioNext-608027 to Dr. Lara-Pezzi; Meet-ITN-317433 to Dr. Enriquez; UE0/MCA1108 to Dr. Acin-Perez), from the Spanish Ministry of Economy and Competitiveness (SAF2015-65722-R and SAF2012-31451 to Dr. Lara-Pezzi; SAF2015-71521-REDC, BFU2013-50448, and SAF2012-32776 to Dr. Enriquez; RyC-2011-07826 to Dr. Acin-Perez; BIO2012-37926 and BIO2015-67580-P to Dr. Vazquez), from the Spanish Carlos III Institute of Health (CPII14/00027 to Dr. Lara-Pezzi; RD12/0042/066 to Drs. Garcia-Pavia and Lara-Pezzi), from the Regional Government of Madrid (2010-BMD-2321 ``Fibroteam´´ to Dr. Lara-Pezzi; 2011-BMD-2402 ``Mitolab´´ to Dr. Enriquez) and the FIS-ISCIII (PRB2-IPT13/0001 and RD12/0042/0056-RIC-RETICS to Dr. Vazquez). This work was also supported by the Plan Estatal de IthornDthornI 2013-2016-European Regional Development Fund (FEDER) ``A way of making Europe,´´ Spain. The CNIC is supported by the Spanish Ministry of Economy and Competitiveness and by the Pro-CNIC Foundation and is a Severo Ochoa Center of Excellence (MINECO award SEV-2015-0505). Drs. Vazquez and Garcia-Pavia have served as consultants for VL39. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose. Drs. Padron-Barthe, Villalba-Orero, and Gomez-Salinero contributed equally to this work and are joint first authors. Robyn Shaw, MD, PhD, served as Guest Editor for this paper.S
A strategy for scaling up access to comprehensive care in adults with Chagas disease in endemic countries: The Bolivian Chagas Platform
BACKGROUND: Bolivia has the highest prevalence of Chagas disease
(CD) in the world (6.1%), with more than 607,186 people with
Trypanosoma cruzi infection, most of them adults. In Bolivia CD
has been declared a national priority. In 2009, the Chagas
National Program (ChNP) had neither a protocol nor a clear
directive for diagnosis and treatment of adults. Although
programs had been implemented for congenital transmission and
for acute cases, adults remained uncovered. Moreover, health
professionals were not aware of treatment recommendations aimed
at this population, and research on CD was limited; it was
difficult to increase awareness of the disease, understand the
challenges it presented, and adapt strategies to cope with it.
Simultaneously, migratory flows that led Bolivian patients with
CD to Spain and other European countries forced medical staff to
look for solutions to an emerging problem. INTERVENTION: In this
context, thanks to a Spanish international cooperation
collaboration, the Bolivian platform for the comprehensive care
of adults with CD was created in 2009. Based on the
establishment of a vertical care system under the umbrella of
ChNP general guidelines, six centres specialized in CD
management were established in different epidemiological
contexts. A common database, standardized clinical forms, a and
a protocolized attention to adults patients, together with
training activities for health professionals were essential for
the model success. With the collaboration and knowledge transfer
activities between endemic and non-endemic countries, the
platform aims to provide care, train health professionals, and
create the basis for a future expansion to the National Health
System of a proven model of care for adults with CD. RESULTS:
From 2010 to 2015, a total of 26,227 patients were attended by
the Platform, 69% (18,316) were diagnosed with T. cruzi, 8,567
initiated anti-parasitic treatment, more than 1,616 health
professionals were trained, and more than ten research projects
developed. The project helped to increase the number of adults
with CD diagnosed and treated, produce evidence-based clinical
practice guidelines, and bring about changes in policy that will
increase access to comprehensive care among adults with CD. The
ChNP is now studying the Platform's health care model to adapt
and implement it nationwide. CONCLUSIONS: This strategy provides
a solution to unmet demands in the care of patients with CD,
improving access to diagnosis and treatment. Further scaling up
of diagnosis and treatment will be based on the expansion of the
model of care to the NHS structures. Its sustainability will be
ensured as it will build on existing local resources in Bolivia.
Still human trained resources are scarce and the high staff
turnover in Bolivia is a limitation of the model. Nevertheless,
in a preliminary two-years-experience of scaling up this model,
this limitations have been locally solved together with the
health local authorities
Sostenibilidad en la Ingeniería Civil. Una experiencia piloto de formación profesional y aprendizaje cooperativo
A Pilot Experience on Cooperative Learning was developed with vocational training students of Advanced Level in Building Construction and Civil Engineering of the Atenea Secondary School (Ciudad Real). The aim was to improve their professional skills in the field of sustainability and, in particular, wastewater treatment by planning, designing, projecting and building artificial wetlands; this a innovative and distinctive competence that will facilitate their employment in an environment with demand for skilled technicians in water purification systems that are more sustainable in both environmental, energy and economical terms. For this purpose, a transdisciplinary team of university professors was formed, who are specialized on building and civil engineering, environmental technology, ecology, ecological engineering, hydraulics, hydrology, geotechnics, geology, geomorphology, geography, territorial planning, teaching and pedagogy. The methodology used was Project Based Learning (PBL), that has been used for some of the team members since 1999 in the Faculty of Civil Engineering of the Universidad de Castilla-La Mancha (UCLM). Students were asked to propose, design and project an artificial wetland to treat wastewater from a rural home, museum or restaurant that they had projected earlier to rehabilitate the ruins of a 19th century water-energy-industrial foundry known as Martinete de Los Pozuelos de Calatrava (Ciudad Real). The major milestones of the pilot experience were: i) Pre-assessment of students knowledge, ii) Lectures to provide new theoretical concepts essential to develop foreseen specific, iii) Independent student work supervised by teachers from closed scripts and supply of teaching materials and literature, iv) Classroom and field workshops, v) Continuous assessment of individual work in class (interest, participation, success in the resolution of the issues raised by the teacher), final evaluation in group through oral presentation and written report, and issuing diplomas for further recognition of free credits, vi) Evaluation of the pilot experience was done by surveying students about methodology, content and development of classes, results obtained and other comments that they wished to include, vii) Dissemination by opening an account in the facebook social network, writing a press release for publication in local media, and professional editing a CD with graphic and teaching materials. The most remarkable result of the pilot is that PBL methodology is a revolution for vocational training students, used to deal with tools and practicalities commonly based on closed standards and protocols; instead, cooperative learning requires facing real limitations, such as a relative lack of information, developing the project with this uncertainty, and making decisions on the level of complexity of the solutions to adopt. This has resulted in an overall very positive experience for the students (over 95%), who were especially pleased with the results (100%) and the content and development of educational activities (more than 95%)
Association of the microsatellite in the 3' untranslated region of the CD154 gene with rheumatoid arthritis in females from a Spanish cohort: a case-control study
CD40–CD154 interaction is an important mediator of inflammation and has been implicated in T helper type 1-mediated autoimmune diseases including rheumatoid arthritis (RA). Linkage studies have shown association of markers in the proximity of the CD154 gene. In the present work we investigated whether specific allele variants of the microsatellite in the 3' UTR of the CD154 gene might modulate the risk of RA. The study, in a case-control setting, included 189 patients and 150 healthy controls from the Canary Islands, Spain. The 24CAs allele was less represented in female patients than in controls (0.444 in controls versus 0.307 in patients, P = 0.006, odds ratio (OR) 0.556, 95% confidence interval (CI) 0.372 to 0.831) but not in males (0.414 versus 0.408), and only when homozygous (P = 0.012; OR 0.35, 95% CI 0.16 to 0.77). We also verified that CD154 association with RA was independent of human leukocyte antigen (HLA) phenotype. A further functional study showed that after stimulation anti-CD3, CD154 mRNA was more stable in CD4+ T lymphocytes from patients with RA bearing the 24CAs allele (mRNA half-life 208 minutes) than in patients without the 24CAs allele (109 minutes, P = 0.009). However, a lower percentage of CD154+CD4+ T lymphocytes was seen in freshly isolated peripheral blood mononuclear cells from patients carrying 24CAs alleles (mean 4.28 versus 8.12; P = 0.033), and also in CD4+ T lymphocytes stimulated with anti-CD3 (median 29.40 versus 47.60; P = 0.025). These results were concordant with the smaller amounts of CD154 mRNA isolated from stimulated T lymphocytes with 24CAs alleles. The CD154 microsatellite therefore seems to affect the expression of the gene in a complex manner that implies not only mRNA stability. These data suggest that the CD154 microsatellite contributes to the regulation of mRNA and protein expression, although further studies will be necessary to elucidate its role in disease predisposition
- …