148 research outputs found
Evaluación técnica Económica entre Alternativas de pavimento flexibles carpeta Asfáltica y Adoquín para el tramo de Carretera Empalme Portillo el Cuá
Efectuar la evaluación técnica-económica de pavimento de carpeta asfáltica y adoquín para el tramo de carretera empalme El Portillo-El Cuá 11.59 km, el cual permita adoptar la opción más viable para su construcción; as como, el análisis de impacto ambiental
Process control by personal computer
This article covers the operation, design procedures and the applications of a microcomputer-based digital dynamic control system (d.d.c.) and underlines how the addition of a simple analogue interface on a small personal computer allows the designer to be come familiar with the digital dynamic control techniques in a real (not simulated) environment. The system described consists of an eight multiplexed input a-to-d converter, a d-to-a converter with power outputs and a six input adder. Thus multiple feedback controlling only one output variable is possible. Alternative interfaces are also described; their object is acquiring data and simplifying the software which the microprocessor needs to make data conversion.Peer ReviewedPostprint (published version
Effects of high-intensity interval versus continuous exercise training on post-exercise heart rate recovery in coronary heart-disease patients.
Background: Heart rate recovery (HRR) has been considered a prognostic and
mortality indicator in both healthy and coronary patients. Physical exercise
prescription has shown improvements in VO2peak and HRR, but most of the studies
have been carried out applying continuous training at a moderate intensity, being very
limited the use of protocols of high intensity interval training in coronary patients.
We aimed to compare the effects of a moderate continous training (MCT) versus a
high intensity interval training (HIIT) programme on VO2 peak and HRR.
Methods: Seventy three coronary patients were assigned to either HIIT or MCT groups
for 8 weeks. Incremental exercise tests in a cycloergometer were performed to obtain
VO2peak data and heart rate was monitored during and after the exercise test to
obtain heart rate recovery data.
Results: Both exercise programmes significantly increase VO2peak with a higher
increase in the HIIT group (HIIT: 4.5± 4.46 ml/kg/min vs MCT: 2.46±3.57 ml/kg/min;
P=0.039). High intensity interval training resulted in a significantly increase in HRR at
the first and second minute of the recovery phase (15,44±7,04 vs 21,22 ±6,62, P
<0,0001 and 23,73±9,64 vs 31,52±8,02, p <0,0001, respectively).
Conclusions: The results of our research show that the application of HIIT to patients
with chronic ischemic heart disease of low risk resulted in an improvement in VO2peak,
and also improvements in post-exercise heart-rate recovery, compared with
continuous training.pre-print792 K
Cambios en los parámetros fisiológicos por diarrea neonatal en crías de alpaca
Alpacas in the pre-weaning stage often present neonatal diarrhoea, usually of infectious type, causing high mortality. This study determined the physiological parameters and their changes in animals with diarrhoea. In total, 79 neonate alpacas less than 60 days of age from Pasco and Junín regions, Peru, were used. Of them, 60 had clinical diarrhoea lasting 1 to 3 days, and 19 were healthy (controls). Heart and respiratory rate, peripheral capillary oxygen saturation, body temperature, capillary refill time, and mucous color were determined. A significant increase in heart rate in crias with diarrhea compared to healthy ones was found (p<0.05). Besides, no differences in other physiological parameters between diseased and apparently healthy offspring was found.Las crías de alpaca en la etapa pre-destete cursan con frecuencia con cuadros diarreicos, por lo general de tipo infeccioso, causantes de alta mortalidad. El presente estudio determinó los parámetros fisiológicos y sus cambios en animales con diarrea. Se utilizaron 79 alpacas neonatas menores de 60 días de edad de las zonas de Pasco y Junín, Perú. De ellas, 60 cursaban con cuadros de diarrea entre 1 a 3 días y 19 estaban sanas (controles). Se determinó la frecuencia cardiaca y respiratoria, saturación de la sangre por la presión parcial de oxígeno, temperatura corporal, tiempo de llenado capilar y coloración de las mucosas. Se encontró un aumento significativo de la frecuencia cardiaca (p<0.05) en crías con diarrea en comparación a las sanas, no habiendo diferencias en los demás parámetros fisiológicos entre crías enfermas y aparentemente sanas
The Los Murcianos zeolite deposit (San José, Almería)
El Yacimiento de Zeolitas de “Los Murcianos”, situado en la provincia de Almería cerca de la localidad de San José (Cabo de Gata), es el único yacimiento de zeolitas en explotación actualmente en España. Se emplaza en rocas volcánicas explosivas de tipo ignimbrita dacítica de la caldera de “Los Frailes”. La alteración hidrotermal de los materiales ignimbríticos ha originado dos tipos de materiales diferentes: zeolitas y bentonitas, estando su disposición controlada por la facturación de la zona. Las zeolitas son mordenitas muy ricas en sílice, de elevada pureza y fórmula estructural Na1.92 K0.52 Ca1.51 Fe0.17 Mg0.15 (Al7.43 Si40.92 O96) 28 H2O. Las bentonitas son montmorillonitas de fórmula (Si7.97Al0.03) O20 (Al2.36Fe3+0.18Mg1.47) (OH)4 [Na0.21K0.13Ca0.13] con cantidades variables de sílice amorfa. Existe una enorme similitud composicional entre zeolitas e ignimbritas, mientras que las bentonitas son claramente diferentes, incluso existen variaciones significativas dentro de ellas. Todos los datos permiten deducir que las génesis de ambos materiales responde a dos procesos diferentes de alteración. La formación de la zeolita no supone una variación de la composición química global de la roca, por lo que las ignimbritas debieron quedar confinadas y alterarse a mordenita mediante un proceso de alteración hidrotermal consistente en desvitrificación e hidratación de la ignimbrita, mientras que, posteriormente, tuvo lugar un proceso de alteración en un sistema abierto ocasionado por la circulación de fluidos a favor de las fracturas, los cuales lixiviaron parte de los elementos alcalinos y alcalino-térreos de las ignimbritas y aportaron otros como Mg, necesarios para la formación de las esmectitas.Los Murcianos is the only zeolite mine in Spain and is located near San José, in the province of
Almería (SE Spain). The mine is located on the western side of the Los Frailes volcanic complex, and the
mineral deposit is emplaced in Miocene dacitic ignimbrites and tuffs. These rocks have been
hydrothermally altered and replaced by zeolites and smectites. The main conduits for hydrothermal fluids
were NW and N-S trending faults that bound the economic mineralization. The zeolite is a silica-rich
mordenite, with a mean formula of Na1.92 K0.52 Ca1.51 Fe0.17 Mg0.15 (Al7.43 Si40.92 O96) 28 H2O, whereas that
of the smectite corresponds to montmorillonite: (Si7.97Al0.03) O20 (Al2.36Fe3+
0.18Mg1.47) (OH)4
[Na0.21K0.13Ca0.13] with variable amounts of amorphous silica. The chemical composition of the zeolites
resembles that of the ignimbrite, whereas the chemistry of the smectites is very different. This suggests
that zeolite formation occurred under confined, isochemical conditions. In addition, the textural study
indicates that devitrification and hydration, during hydrothermal alteration, played a major role in
zeolite formation. On the other hand, movement of fluids along faults would have resulted in leaching of
alkaline and alkaline earth elements with the exception of Mg which was introduced to the system. We
further suggest the mineral deposit formed during at least two episodes of fluid circulation.Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEInstituto Geológico y Minero de Españapu
Mechanical efficiency of high versus moderate intensity aerobic exercise in coronary heart disease patients: A randomized clinical trial.
Background: Mechanical efficiency (ME) refers to the ability of an individual to transfer energy
consumed by external work. A decreased ME, could represent an increased energy cost during exercise
and may, therefore, be limited in terms of physical activity. This study aimed to compare the influence
of two different exercise protocols: moderate continuous training (MCT) versus high intensity interval
training (HIIT), as part of a cardiac rehabilitation program on ME values among coronary patients.
Methods: One hundred and ten coronary patients were assigned to either HIIT or MCT groups for
8 weeks. Incremental exercise tests in a cycle ergometer were performed to obtain VO2peak. Net energy
expenditure (EE) and ME were obtained at intensities corresponding to the first (VT1) and second (VT2)
ventilatory thresholds, and at VO2peak.
Results: Both exercise programs significantly increase VO2peak with a higher increase in the HIIT
group (2.96 ± 2.33 mL/kg/min vs. 3.88 ± 2.40 mL/kg/min, for patients of the MCT and HIIT groups,
respectively, p < 0.001). The ME at VO2peak and VT2 only significantly increased in the HIIT group.
At VT1, ME significantly increased in both groups, with a greater increase in the HIIT group (2.20 ±
± 6.25% vs. 5.52 ± 5.53%, for patients of the MCT and HIIT groups, respectively, p < 0.001).
Conclusions: The application of HIIT to patients with chronic ischemic heart disease of low risk resulted in a greater improvement in VO2peak and in ME at VT1, than when MCT was applied. Moreover,
only the application of HIIT brought about a significant increase in ME at VT2 and at VO2peak. (Cardiol
J 2019; 26, 2: 130–137)post-print251 K
Functionality and Quality of Life with Parkinson’s Disease after Use of a Dynamic Upper Limb Orthosis: A Pilot Study
Parkinson’s disease (PD) is a chronic, neurodegenerative movement disorder, whose symptoms have a negative impact on quality of life and functionality. Although its main treatment is pharmacological, non-pharmacological aids such as the dynamic elastomeric fabric orthosis (DEFO) merit an evaluation. Our objective is to assess the DEFO in upper limb (UL) functional mobility and in the quality of life of PD patients. A total of 40 patients with PD participated in a randomized controlled crossover study, and were assigned to a control group (CG) and to an experimental group (EG). Both groups used the DEFO for two months, the experimental group the first two months of the study and the control group the last two. Motor variables were measured in the ON and OFF states at the baseline assessment and at two months. Differences from the baseline assessment were observed in some motor items of the Kinesia assessment, such as rest tremor, amplitude, rhythm or alternating movements in the ON and OFF states with and without orthosis. No differences were found in the unified Parkinson’s disease rating scale (UPDRS) or the PD quality-of-life questionnaire. The DEFO improves some motor aspects of the UL in PD patients but this does not translate to the amelioration of the standard of functional and quality-of-life scales
Optimización en el diseño de lagunas de estabilización con programación no lineal
El estudio presenta un modelo matemático de optimización para el diseño de sistemas lagunares integrado por dos lagunas: facultativa y de maduración. El modelo tiene como función objetivo el costo y considera cuatro variables de decisión: tiempo de retención hidráulico y número de mamparas en la laguna facultativa; en la laguna de maduración, también número de mamparas y tiempo de retención. Se consideran como restricciones los coliformes fecales y la materia orgánica. Dicho modelo resultó ser no lineal, ya que las relaciones entre las variables no son proporcionales. Se diseñó un sistema lagunar utilizando la metodología tradicional adoptada por la Comisión Nacional del Agua para México, luego se aplicó el modelo matemático. Se lleva a cabo una comparación de los resultados, los cuales indican una reducción del tiempo de retención de 14.16% y una disminución del costo de 12.04%. El resultado anterior es importante, ya que la principal desventaja de estos sistemas es el requerimiento de terreno. Se incluye, además, el análisis de sensibilidad de la función objetivo y las restricciones consideradas. El citado análisis es sensible a la variación de los parámetros. Ambos estudios cumplen perfectamente con las condiciones de calidad del agua tratada que indica la normatividad para el vertido a los cuerpos receptores. Se recomienda llevar a cabo otros estudios de optimización, considerando diferentes configuraciones
Use of mixed methods research in intervention studies to increase young people’s interest in STEM: A systematic methodological review
IntroductionMixed methods research intervention studies integrate quantitative evaluation approaches, such as randomized controlled trials and quasi-experimental designs, with qualitative research to evaluate the effectiveness, efficacy, or other results of an intervention or program. These types of studies, which have attracted growing attention in recent years, enhance the scope and rigor of the evaluation. While various frameworks that summarize the justifications for carrying out these types of studies and provide implementation guidance have been published in the last few years in the health sciences, we do not know whether such frameworks have been properly implemented in the social and educational sciences. This review examined the methodological features and reporting practices of mixed methods intervention studies aimed at increasing young people’s interest in STEM.MethodsA systematic search was carried out in APA PsycNET, ERIC, ProQuest, Scopus, and Web of Science, and a hand search in 20 journals. We included peer-reviewed English-language articles that reported intervention studies with a quantitative component measuring outcomes specific to increasing secondary school students’ interest in STEM fields, a qualitative component conducted before, during, or after the quantitative component, and evidence of integration of both components. Qualitative content analysis and ideal-type analysis were used to synthesize the findings.ResultsWe found 34 studies; the majority published in the last ten years. Several patterns of mixed methods application were described in these studies, illustrating the unique insights that can be gained by employing this methodology. The reporting quality of the included studies was generally adequate, especially regarding the justification for using a mixed methods intervention design and the integration of the quantitative and qualitative components. Nonetheless, a few reporting issues were observed, such as a lack of detail in the presentation of the mixed methods design, an inadequate description of the qualitative sampling and analysis techniques, and the absence of joint displays for representing integration.DiscussionAuthors must pay attention to these issues to ensure that the insights obtained by the use of mixed methods research are effectively communicated
La ciudad empática. Hacia un nuevo modelo de sociabilidad urbana
La ciudad es una construcción física y social realizada por el hombre,
que afecta a la vida cotidiana y diaria de los ciudadanos y que, por tanto, se ha
convertido en el foco principal de las relaciones sociales y humanas, con capacidad
para responder a las necesidades y garantizar una mejora de la calidad de vida.
Es por ello que, se hace necesario el análisis y estudio de la habitabilidad y calidad
de vida en los contextos urbanos, como paradigma y referencia para el desarrollo
de la vida colectiva y social a través del espacio público y el tejido urbano. La
ciudad actual ha relegado los espacios de convivencia y relación de ámbitos públicos
a privados, como consecuencia, entre otras, de la presencia de nuevos elementos
que paulatinamente han adquirido más protagonismo, como es el coche o la
inexistencia de equipamientos que cualifiquen el espacio público. De este modo,
los procesos emergentes de renovación urbana son esenciales para el disfrute de la
vida en la ciudad, especialmente los basados en procesos participativos.
La investigación busca generar una metodología de análisis cualitativo del espacio
público a través de una investigación-acción que desarrollará una herramienta,
DEU (Diagnóstico de Empatía Urbana), que permitirá, por un lado, realizar una
evaluación de las localizaciones por parte del técnico y, por otro, obtener la valoración
que la población implicada otorgue a las mismas. Este proceso nos permitirá
evaluar el grado de empatía que los contextos a estudiar ofrecen a los usuarios
para los que están destinados y, además, disponer de elementos de mejora para
poder definir estrategias y propuestas transformadoras que provengan directamente
de la propia experiencia de dichos usuario
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