Mechanical analysis of Genoa 03 stirling engine

Due to the new technologies development based on renewable sources of energy, in recent years Stirling engines have become very important in the energetic sector. Many of them do not allow the use of fluid lubricants and, thus, the effect of friction losses is important. For this purpose, a mathematical model has been developed based on the force balance in the crankshaft using the pressure distribution in the cylinders. The aim of this work is to characterize the mechanical losses in a Genoa 03 Stirling engine using a numerical model and experimentally via the drag method. The results of this model have been compared with those obtained experimentally on Genoa 03 Stirling engine. In the experimental results, a proportional increase in friction torque due to the average pressure and the speed of the crankshaft is observed. The first of these is caused by an increase of dry friction forces and the second, by the viscous friction between the working fluid and the inner walls of the engine. Also in this paper, irreversible processes in a beta type Stirling engine have been investigated in order to highlight the impact of losses on mechanical power and its performance. This article develops the first study of the mechanical losses of Genoa 03 experimental Stirling engine, which has an output power of 3 kW. Although the model response follows the same trends as the experiments, those simplifications provide errors which become more significant as the engine speed increases.Ministerio de Economía y Competitividad ENE2013-43465-

Interactions of AChE with Aβ Aggregates in Alzheimer’s Brain: Therapeutic Relevance of IDN 5706

Acetylcholinesterase (AChE; EC 3.1.1.7) plays a crucial role in the rapid hydrolysis of the neurotransmitter acetylcholine, in the central and peripheral nervous system and might also participate in non-cholinergic mechanism related to neurodegenerative diseases. Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by a progressive deterioration of cognitive abilities, amyloid-β (Aβ) peptide accumulation and synaptic alterations. We have previously shown that AChE is able to accelerate the Aβ peptide assembly into Alzheimer-type aggregates increasing its neurotoxicity. Furthermore, AChE activity is altered in brain and blood of Alzheimer’s patients. The enzyme associated to amyloid plaques changes its enzymatic and pharmacological properties, as well as, increases its resistant to low pH, inhibitors and excess of substrate. Here, we reviewed the effects of IDN 5706, a hyperforin derivative that has potential preventive effects on the development of AD. Our results show that treatment with IDN 5706 for 10 weeks increases brain AChE activity in 7-month-old double transgenic mice (APPSWE–PS1) and decreases the content of AChE associated with different types of amyloid plaques in this Alzheimer’s model. We concluded that early treatment with IDN 5706 decreases AChE–Aβ interaction and this effect might be of therapeutic interest in the treatment of AD

A Comparative Analysis of Phytovolume Estimation Methods Based on UAV-Photogrammetry and Multispectral Imagery in a Mediterranean Forest

Management and control operations are crucial for preventing forest fires, especially in Mediterranean forest areas with dry climatic periods. One of them is prescribed fires, in which the biomass fuel present in the controlled plot area must be accurately estimated. The most used methods for estimating biomass are time-consuming and demand too much manpower. Unmanned aerial vehicles (UAVs) carrying multispectral sensors can be used to carry out accurate indirect measurements of terrain and vegetation morphology and their radiometric characteristics. Based on the UAV-photogrammetric project products, four estimators of phytovolume were compared in a Mediterranean forest area, all obtained using the difference between a digital surface model (DSM) and a digital terrain model (DTM). The DSM was derived from a UAV-photogrammetric project based on the structure from a motion algorithm. Four different methods for obtaining a DTM were used based on an unclassified dense point cloud produced through a UAV-photogrammetric project (FFU), an unsupervised classified dense point cloud (FFC), a multispectral vegetation index (FMI), and a cloth simulation filter (FCS). Qualitative and quantitative comparisons determined the ability of the phytovolume estimators for vegetation detection and occupied volume. The results show that there are no significant differences in surface vegetation detection between all the pairwise possible comparisons of the four estimators at a 95% confidence level, but FMI presented the best kappa value (0.678) in an error matrix analysis with reference data obtained from photointerpretation and supervised classification. Concerning the accuracy of phytovolume estimation, only FFU and FFC presented differences higher than two standard deviations in a pairwise comparison, and FMI presented the best RMSE (12.3 m) when the estimators were compared to 768 observed data points grouped in four 500 m2 sample plots. The FMI was the best phytovolume estimator of the four compared for low vegetation height in a Mediterranean forest. The use of FMI based on UAV data provides accurate phytovolume estimations that can be applied on several environment management activities, including wildfire prevention. Multitemporal phytovolume estimations based on FMI could help to model the forest resources evolution in a very realistic way

Formulación de un plan de negocios para el desarrollo y comercialización de un aplicativo móvil encaminado a la gestión de reservas de canchas deportivas en el sector de Chapinero y Teusaquillo

EmprendimientoEl aplicativo desarrollado permitirá la gestión de reserva de canchas deportivas, facilitando al usuario el acceso y brindando un servicio de calidad. Se realiza un estudio de mercados para identificar la población objetivo y los establecimientos rentables para la adquisición de nuestro producto, posteriormente se elabora un estudio organizacional, técnico y financiero los cuales permite determinar la rentabilidad del aplicativo.INTRODUCCIÓN 1. GENERALIDADES 2. ESTUDIO DE MERCADO 3. ESTUDIO ADMINISTRATIVO 4. ESTUDIO TÉCNICO 5. ESTUDIO FINANCIERO 6. CONCLUSIONES 7. RECOMENDACIONES BIBLIOGRAFÍAPregradoIngeniero Industria

Excited state quantum phase transitions in the bending spectra of molecules

We present an extension of the Hamiltonian of the two dimensional limit of the vibron model encompassing all possible interactions up to four-body operators. We apply this Hamiltonian to the modeling of the experimental bending spectrum of fourteen molecules. The bending degrees of freedom of the selected molecular species include all possible situations: linear, bent, and nonrigid equilibrium structures; demonstrating the flexibility of the algebraic approach, that allows for the consideration of utterly different physical cases with a general formalism and a single Hamiltonian. For each case, we compute predicted term values used to depict the quantum monodromy diagram, the Birge-Sponer plot, the participation ratio. We also show the bending energy functional obtained using the coherent --or intrinsic-- state formalism.Comment: 67 pages, 18 tables and 15 figure

Anharmonicity-induced excited-state quantum phase transition in the symmetric phase of the two-dimensional limit of the vibron model

We acknowledge useful discussions with José Miguel Arias, Manuel Calixto, Pedro Pérez Fernández, and Lea Santos. This project received funding from the European Union's Horizon 2020 research and innovation program under Marie Skłodowska-Curie Grant Agreement No. 872081 and from Grant No. PID2019-104002GB-C21 funded by MCIN/AEI/ 10.13039/501100011033 and, as appropriate, by ERDF A way of making Europe, by the European Union, or by the European Union NextGenerationEU/PRTR. This work was also partially supported by the Consejería de Transformación Económica, Industria, Conocimiento y Universidades, Junta de Andalucía, and European Regional Development Fund through Grants No. UHU-1262561 (J.K.-R. and F.P.-B.) and No. PY2000764 and by the Ministerio de Ciencia, Innovación y Universidades (Grant No. COOPB20364) (M.C.). Computing resources supporting this work were provided by the CEAFMC and Universidad de Huelva High Performance Computer located at the Campus Universitario el Carmen and funded by FEDER/MINECO Project No. UNHU-15CE-2848.In most cases, excited-state quantum phase transitions can be associated with the existence of critical points (local extrema or saddle points) in a system’s classical limit energy functional. However, an excited-state quantum phase transition might also stem from the lowering of the asymptotic energy of the corresponding energy functional. One such example occurs in the two-dimensional (2D) limit of the vibron model, once an anharmonic term in the form of a quadratic bosonic number operator is added to the Hamiltonian. This case has been studied in the broken-symmetry phase [Pérez-Bernal and Álvarez-Bajo, Phys. Rev. A 81, 050101 (2010)]. In the present work we delve further into the nature of this excited-state quantum phase transition and we characterize it in the symmetric phase of the model, making use of quantities such as the effective frequency, the expected value of the quantum number operator, the participation ratio, the density of states, and the quantum fidelity susceptibility. In addition to this, we extend the usage of the quasilinearity parameter, introduced in molecular physics, to characterize the phases in the spectrum of the anharmonic 2D limit of the vibron model and a practical analysis is included with the characterization of the critical energies for the linear isomers HCN and HNC.CEAFMCConsejería de Transformación Económica, Industria, Conocimiento y Universidades, Junta de AndalucíaEuropean Union NextGenerationEU/PRTRMCINUniversidad de Huelva High Performance ComputerMinisterio de Ciencia, Innovación y Universidades COOPB20364European CommissionMinisterio de Economía y Competitividad UNHU-15CE-2848Horizon 2020 872081, PID2019-104002GB-C21European Regional Development Fund PY2000764, UHU-1262561Junta de AndalucíaAgencia Estatal de Investigació

An Approach to Global Rovibrational Analysis Based on Anharmonic Ladder Operators: Application to Hydrogen Selenide (H80 2 Se)

An algebraic approach to perform global rovibrational analysis of molecular spectra is presented. The approach combines the onedimensional limit of the vibron model with rotational degrees of freedom. The model is based on the expression of the phase space Hamiltonian in terms of anharmonic ladder operators and the use of a symmetry-adapted basis set given by the linear combination of products of local vibrational and rotational wavefunctions. As an example we model the rovibrational spectra of a bent triatomic molecule, providing a global analysis for vibrational bands up to polyad 12 and Jmax=5 of Hydrogen Selenide (H2Se). Satisfactory fits of vibrational and rovibrational energies are obtained. A prediction of 2579 rovibrational energies up to J ≤ 5 and polyad 12 for the 140 lowest vibrational bands is also obtained. A possible extension of the model to reach spectroscopic quality results in larger molecular systems is also given

Evaluación de factores de riesgo de enfermedades crónicas no transmisibles durante primer semestre 2015, en escolares de sexo femenino bajo el proyecto Vida Sana de la Municipalidad de Providencia

Tesis (Tecnólogo Médico, mención bioanálisis clínico, inmunohematología y banco de sangre)Hoy en día, la obesidad es un tema muy importante de salud pública, ya que día a día el porcentaje de personas obesas, tanto en Chile como en el mundo aumenta por los altos índices de sedentarismo en la población y el desorden alimenticio que presentan. Más alarmante aún es cuando hablamos de la obesidad infantil, se dice que es el problema de salud pública más grave del siglo XXI según consigna la Organización Mundial de la Salud (OMS). Según fuentes de la OMS este problema, está afectando progresivamente a países de bajos y medianos ingresos principalmente, sobre todo en el medio urbano, y se calcula que en 2010 hay 42 millones de niños con sobrepeso en todo el mundo, de los que cerca de 35 millones viven en países en vías de desarrollo. En Chile la obesidad infantil va en incremento, por lo mismo, el Ministerio de Salud (MINSAL) junto con la Municipalidad de Providencia idearon en conjunto el proyecto “Vida Sana”, donde invitan a niños y adolescentes de colegios de la comuna a inscribirse en el programa para disminuir los factores de riesgo asociados a Enfermedades Crónicas No Transmisibles (ECNTs), las cuales son enfermedades de larga duración, lenta progresión, que no se resuelven espontáneamente y que rara vez logran una curación total, como la Diabetes Mellitus (DM) , la Hipertensión Arterial y la obesidad. Nuestro propósito es evaluar si el objetivo general del proyecto se cumple, a través de exámenes bioquímicos, tales como HOMA, colesterol total, triglicéridos y glicemia en ayunas, para evidenciar si existe una disminución en el riesgo a desarrollar una ECNT, debido a que éstos exámenes aportan parámetros cuantificables, los cuales están estrechamente relacionados, debido a que un descenso en éstos implica una disminución en el riesgo de contraer alguna de éstas enfermedades