Miracle-dz/UniFAR-FTUs huggingface dataset:
Aceptación de los estudiantes universitarios en el uso de los sistemas e-learning Moodle desde la perspectiva del modelo TAM.// Acceptance of university students in the use of Moodle e-learning systems from the perspective of the TAM model.

El propósito de este artículo es presentar un estudio donde se consideraron los incentivos que tienen los estudiantes universitarios en el uso real de sistemas e-learning para promover el aprendizaje auto dirigido y colaborativo en el contexto de sus cursos universitarios. Además, se propone un esquema teórico de investigación en base al modelo TAM. Se construyó un cuestionario en línea, que se distribuyó por correo electrónico a todos los alumnos de la carrera de Finanzas y Auditoria de la Universidad de las Fuerzas Armadas. En total 128 estudiantes universitarios respondieron. Se realizó un análisis exploratorio y confirmatorio utilizando Mínimos Cuadrados Parciales (PLS) para validar el modelo de investigación. Se establecieron las relaciones existentes entre la experiencia, normas subjetivas, entretenimiento percibido, ansiedad por la computadora, auto eficiencia computacional, la utilidad percibida y la facilidad de uso percibida, la actitud de aprendizaje y el uso real de los sistemas e-learning. Como resultado en el modelo propuesto se obtuvo una varianza explicada del 49,7% en el uso de dicho sistema. También se encontró que la mayoría de los estudiantes se interesaron en aprender con la plataforma Moodle y lo consideraron como una herramienta de aprendizaje útil. AbstractThe purpose of this article is to present a study that considered the factors that university students have in the real use of e-learning systems to promote self-directed and collaborative learning in the context of their university courses. In addition, a theoretical research scheme based on the TAM model was proposed and an online questionnaire was constructed, which was distributed by e-mail to all students of the Finance and Audit career at the University of the Armed Forces. In total, 128 university students responded. An exploratory and confirmatory analysis was carried out using Partial Least Squares (PLS) to validate the research model. The relationships between experience, subjective norms, perceived entertainment, computer anxiety, computational self-efficiency, perceived usefulness and perceived ease of use, the learning attitude and the actual use of e-learning systems were made. As a result of the proposed model, an explained variance of 49.7% was obtained in the use of this system and it was found that most of the students were interested in learning with the Moodle platform and considered it a useful learning tool.
Understanding the Thermal Implications of Multi-Core Architectures

Multicore architectures are becoming the main design paradigm for current and future processors. The main reason is that multicore designs provide an effective way of overcoming instruction-level parallelism (ILP) limitations by exploiting thread-level parallelism (TLP). In addition, it is a power and complexity-effective way of taking advantage of the huge number of transistors that can be integrated on a chip. On the other hand, today's higher than ever power densities have made temperature one of the main limitations of microprocessor evolution. Thermal management in multicore architectures is a fairly new area. Some works have addressed dynamic thermal management in bi/quad-core architectures. This work provides insight and explores different alternatives for thermal management in multicore architectures with 16 cores. Schemes employing both energy reduction and activity migration are explored and improvements for thread migration schemes are proposed.
A Fast Image Reconstruction Algorithm of Electrical Capacitance Tomography Based on Engle Criterion

To improve the speed and quality of the reconstruction image for Electrical Capacitance Tomography (ECT), a fast image reconstruction algorithm based on Engle criterion is proposed. ECT image reconstruction is an ill-posed problem, and Tikhonov regularization is employed to get the stable solution. Engle criterion is used to choice regularization parameter. A further research about three-order method for fast choosing regularization parameter is proposed. Simulation results show that the proposed method has fast convergence rate and the reconstruction image quality is improved markedly.
Quadratic Programming Approach to Glottal Inverse Filtering by Joint Norm-1 and Norm-2 Optimization

This study proposes an approach for glottal inverse filtering of acoustic speech signals using quadratic programming (QPR). The method aims to jointly model the effect of vocal tract and lip radiation with a single filter whose coefficients are optimized using QPR. This optimization is based on the principles of closed phase analysis, where the contribution of the glottal source is attenuated in optimizing the inverse model of the vocal tract. By expressing the optimization problem in terms of the output of a filter, we can apply physically motivated optimization such as flatness of the closed phase. The proposed method was objectively evaluated using a synthetic Liljencrants–Fant model based test set of sustained vowels, as well as a real speech test set where the glottal flow estimates’ closed phases were compared in terms of their flatness. The results based on synthetic speech indicate that the proposed method is robust to changes in <inline-formula><tex-math notation="LaTeX">$f_0$</tex-math></inline-formula>, and state-of-the-art quality results were obtained for high-pitched voices, when <inline-formula> <tex-math notation="LaTeX">$f_0$</tex-math></inline-formula> is in the range 330–450 Hz. The results based on real speech indicate that the proposed method produces glottal flow estimates that have flatter closed phases with less formant ripple in comparison to estimates computed with known reference methods.
Imaging-Based Patient Selection and Endovascular Therapy of Ischemic Stroke

AbstractThe positive results of recent trials for the treatment of acute ischemic stroke have highlighted the importance of imaging selection before endovascular therapy. We performed a stratified meta-analysis to confirm this new understanding.We searched EMBASE, PubMed, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov in April 2015 for randomized controlled trials evaluating the effect of endovascular treatment in patients with acute ischemic stroke. The meta-analysis was stratified by whether computed tomographic angiography (CTA) was used to select patients. Outcome data were pooled using fixed-effects models.Seven randomized controlled trials with 2217 patients were included in this study. Endovascular therapy significantly increased the rate of 90-day functional independence (a modified Rankin score of 0–2) in patients with a CTA-confirmed large-vessel occlusion (relative risk [RR] = 1.75, 95% confidence interval [CI]: 1.48–2.06, I2 = 0.0%), and reduced 90-day mortality in patients with occlusion stroke with a small ischemic core (RR = 0.58, 95% CI: 0.37–0.89, I2 = 0.0%). The functional benefit was significantly greater in patients with CTA-based selection than in those without (Z = 5.04, P < 0.001). The mortality benefit was significantly greater in patients with a large-vessel occlusion and a small ischemic core than in those without CTA-based selection (Z = 2.04, P = 0.041). There was no evidence of between-study heterogeneity or publication bias.This meta-analysis showed the effect of vascular imaging on identifying patients with acute ischemic stroke with a proximal vessel occlusion and a small ischemic core, who would benefit from endovascular therapy.
A Nonlinear Attitude Observer Based on Active Vision and Inertial Measurements

This paper presents an experimentally evaluated solution to the problem of estimating the attitude of a rigid body using rate gyros and a pan-tilt camera. A nonlinear attitude observer combines angular velocity measurements obtained from rate gyros with images of a planar scene provided by the camera. By directly exploiting the sensor information, a stabilizing feedback law is introduced, and exponential convergence to the origin of the estimation errors is shown. Additionally, an active-vision system is proposed that relies on an image-based exponentially input-to-state-stable control law for the pan and tilt angular rates of the camera to keep the features in the image plane. Using recent results in geometric numerical integration, a multirate implementation of the observer is proposed, which exploits the complementary bandwidth of the sensors. Practical considerations, such as the lens-distortion compensation and the computation of suitable observer feedback gains, are considered. Experimental results obtained with a high-accuracy motion rate table demonstrate the high level of performance attained by the proposed solution.
Loss of F-box Only Protein 2 (Fbxo2) Disrupts Levels and Localization of Select NMDA Receptor Subunits, and Promotes Aberrant Synaptic Connectivity

NMDA receptors (NMDARs) play an essential role in some forms of synaptic plasticity, learning, and memory. Therefore, these receptors are highly regulated with respect to their localization, activation, and abundance both within and on the surface of mammalian neurons. Fundamental questions remain, however, regarding how this complex regulation is achieved. Using cell-based models and F-box Only Protein 2 (Fbxo2) knock-out mice, we found that the ubiquitin ligase substrate adaptor protein Fbxo2, previously reported to facilitate the degradation of the NMDAR subunit GluN1 in vitro, also functions to regulate GluN1 and GluN2A subunit levels in the adult mouse brain. In contrast, GluN2B subunit levels are not affected by the loss of Fbxo2. The loss of Fbxo2 results in greater surface localization of GluN1 and GluN2A, together with increases in the synaptic markers PSD-95 and Vglut1. These synaptic changes do not manifest as neurophysiological differences or alterations in dendritic spine density in Fbxo2 knock-out mice, but result instead in increased axo-dendritic shaft synapses. Together, these findings suggest that Fbxo2 controls the abundance and localization of specific NMDAR subunits in the brain and may influence synapse formation and maintenance.
Using Twitter to Predict Sales: A Case Study

This paper studies the relation between activity on Twitter and sales. While research exists into the relation between Tweets and movie and book sales, this paper shows that the same relations do not hold for products that receive less attention on social media. For such products, classification of Tweets is far more important to determine a relation. Also, for such products advanced statistical relations, in addition to correlation, are required to relate Twitter activity and sales. In a case study that involves Tweets and sales from a company in four countries, the paper shows how, by classifying Tweets, such relations can be identified. In particular, the paper shows evidence that positive Tweets by persons (as opposed to companies) can be used to forecast sales and that peaks in positive Tweets by persons are strongly related to an increase in sales. These results can be used to improve sales forecasts and to increase sales in marketing campaigns.
Macromolecular physiology of plastids. IX. Development of plastid membranes during greening of dark-grown barley seedlings.

The development of plastid membranes was studied in relation to chlorophyll accumulation in dark-grown barley seedlings of various ages after transfer to light. Quantitative electron microscopy showed that the prolamellar body membranes are reorganized into primary lamellar layers which contain sufficient membranes to support grana formation during 24 h of greening. Structural reorganization of the plastid membranes is completed rapidly in young seedlings, but is slow in older seedlings. Chlorophyll accumulates rapidly in young leaves after a short lag. In older leaves there is a longer lag phase before the onset of chlorophyll synthesis, and the final rate of synthesis is lower. Shortly after transferring to light, the crystalline prolamellar bodies in the etioplasts are transformed and then dispersed into lamellar layers with numerous perforations and protuberances. Before the phase of rapid chlorophyll synthesis, many small-diameter 2-disk grana are formed. When chlorophyll begins to accumulate, the perforations are rapidly eliminated from the lamellar layers and a maximum number of 2-disk grana are formed. As greening proceeds additional disks are added to these original 2-disk grana. During the phase of rapid chlorophyll synthesis, pairing of the lamellae is positively correlated with the accumulation of chlorophyll. During greening less chlorophyll appears to be incorporated into the paired regions of the lamellae in young leaves as compared to old leaves. The results on the structural aspects of plastid development are discussed in relation to the formation of photosynthetic capacity.
Complete mitochondrial genome of Muricea crassa and Muricea purpurea (Anthozoa: Octocorallia) from the eastern tropical Pacific

We sequenced the complete mitogenomes of two eastern tropical Pacific gorgonians, Muricea crassa and Muricea purpurea, using NGS technologies. The assembled mitogenomes of M. crassa and M. purpurea were 19,586 bp and 19,358 bp in length, with a GC-content ranging from 36.0% to 36.1%, respectively. The two mitogenomes had the same gene arrangement consisting of 14 protein-coding genes, two rRNAs and one tRNA. Mitogenome identity was 98.5%. The intergenic regions between COB and NAD6 and between NAD5 and NAD4 were polymorphic in length with a high level of nucleotide diversity. Based on a concatenated dataset of 14 mitochondrial protein-coding genes we inferred the phylogeny of 26 octocoral species.
Future real-time testing and evaluation computing environments

The authors explore the requirements for an integrated, high performance, real-time computing environment capable of testing and evaluating future aerospace systems. It is pointed out that the effective testing and evaluation of future aerospace systems will require the integration of theoretical, experimental, and computational methodologies. Integrating these methodologies will require the development of an integrated simulation framework that couples the computational capabilities that have evolved independently of one another to support these disciplines. The balanced architectures inherent within current and future supercomputing technologies can provide a high performance platform for facilitating this integration. Some examples of how these relationships among methodologies are being exploited are presented, including a nuclear weapon design example, a crash testing example, and a computational fluid dynamics example. <<ETX>>
Modelling volatility using GARCH models: evidence from Egypt and Israel

This paper examines the use of GARCH-type models for modelling volatility and explaining financial market risk. We use daily data from Egypt (CMA General index) and Israel (TASE-100 index). Various time series methods are employed, including the simple GARCH model, as well as exponential GARCH, threshold GARCH, asymmetric component GARCH, the component GARCH and the power GARCH model. We find strong evidence that daily returns can be characterised by the above models. For both markets, we conclude that increased risk will not necessarily lead to a rise in the returns. The most volatile series is CMA index from Egypt, because of the uncertainty in prices (and economy) over the examined period. These findings are strongly recommended to financial managers and modellers dealing with international markets.
An optimal replenishment strategy in energy harvesting wireless networks with a mobile charger

Energy harvesting wireless network is an emerging paradigm where the wireless nodes harvest energy to increase their lifetime. Due to high potential for a large variety of applications, such networks have drawn considerable attention in both industry and academia. In this paper, we consider the energy replenishment problem when the wireless nodes not only harvest energy from the ambient environment but also may receive energy from a mobile charger. We propose an optimal energy replenishment strategy using stochastic inventory theory to derive the optimal amount of energy supplied by the mobile charger. The simulation results show that our proposed scheme not only optimizes the energy utilization, but also improves the economic benefit of the wireless nodes.
Second-order Convex Splitting Schemes for Gradient Flows with Ehrlich-Schwoebel Type Energy: Application to Thin Film Epitaxy

We construct unconditionally stable, unconditionally uniquely solvable, and second-order accurate (in time) schemes for gradient flows with energy of the form $\int_\Omega ( F(\nabla\phi({\bf x})) + \frac{\epsilon^2}{2}|\Delta\phi({\bf x})|^2 ) d{\bf x}$. The construction of the schemes involves the appropriate combination and extension of two classical ideas: (i) appropriate convex-concave decomposition of the energy functional and (ii) the secant method. As an application, we derive schemes for epitaxial growth models with slope selection ($F({\bf y})= \frac14(|{\bf y}|^2-1)^2$) or without slope selection ($F({\bf y})=-\frac12\ln(1+|{\bf y}|^2)$). Two types of unconditionally stable uniquely solvable second-order schemes are presented. The first type inherits the variational structure of the original continuous-in-time gradient flow, while the second type does not preserve the variational structure. We present numerical simulations for the case with slope selection which verify well-known physical scaling laws for the long time coarsening process.
Optimal Asset Allocation under Quadratic Loss Aversion

We study the asset allocation of a quadratic loss-averse (QLA) investor and derive conditions under which the QLA problem is equivalent to the mean-variance (MV) and conditional value-at-risk (CVaR) problems. Then we solve analytically the two-asset problem of the QLA investor for a risk-free and a risky asset. We find that the optimal QLA investment in the risky asset is finite, strictly positive and is minimal with respect to the reference point for a value strictly larger than the risk-free rate. Finally, we implement the trading strategy of a QLA investor who reallocates her portfolio on a monthly basis using 13 EU and US assets. We find that QLA portfolios (mostly) outperform MV and CVaR portfolios and that incorporating a conservative dynamic update of the QLA parameters improves the performance of QLA portfolios. Compared with linear loss-averse portfolios, QLA portfolios display significantly less risk but they also yield lower returns.
Implementation and evaluation of alternative process schedulers in MINIX

Minix is a Unix clone Operating System, designed by Tanembaum ([2],[3]) to allow beginners to do practical training in Operating Systems area.In this context the present paper describes the work done by a group of students implementing alternative process schedulers disciplines and their evaluation comparing performance estimates.Some unexpected deviations in the original implementation (Minix V. 1.0), found during software development, are also reported.
Amyloid Beta Peptide‐Induced Cerebral Neuronal Loss Is Mediated By Caspase‐3 In Vivo

Amyloid beta peptide (Aβ) is widely believed to play a central and etiological role in Alzheimer disease (AD). Aβ has been shown to have cytotoxic effects in neural cells, although the mechanism by which it does this is still unclear. To examine the involvement of the apoptotic cascade in Aβ-induced cell death, we used mice deficient in caspase-3 (CPP 32), a key protease in this cascade. We microinjected Aβ1–40 into hippocampal regions of the brains of adult mice because AD is an adult-onset disease. We found significant cellular loss in the hippocampal regions of wild-type mice and dramatic rescue of neuronal cell death in caspase-3-deficient mice, with a gene dosage effect. In addition to adult mice, we observed little Aβ-induced death of cultured neurons prepared from fetal brains of caspase-3-deficient mice but did observe death of such neurons from wild-type mice. The difference in Aβ-induced neuronal death between wild-type and caspase-3-deficient mice was highly significant, indicating that Aβ-induced neuronal death is mediated in vivo as well as in vitro by the caspase-3 apoptotic cascade.
Novelty and Reinforcement Learning in the Value System of Developmental Robots

The value system of a developmental robot signals the occurrence of salient sensory inputs, modulates the mapping from sensory inputs to action outputs, and evaluates candidate actions. In the work reported here, a low level value system is modeled and implemented. It simulates the non-associative animal learning mechanism known as habituation effect. Reinforcement learning is also integrated with novelty. Experimental results show that the proposed value system works as designed in a study of robot viewing angle selection.
High-Level Modeling and Exploration of Reconfigurable MPSoCs

This paper presents a novel methodology for modeling partially dynamic reconfigurable hardware at transaction-level. We cover the lack of tools and mechanisms for the design of reconfigurable logic at system-level and for the exploration of the different configurations of such architectures. The presented mechanisms have been implemented in ReSP, a transaction-level simulation platform especially targeted to multi-processor embedded architectures. In our methodology we allow the definition of the reconfigurable functionalities through scripted languages, therefore the switching of any software function for a hardware one, the modeling the configuration delays, area use, etc., can be easily performed (even at runtime). Overall, the methodology enables a powerful exploration of the system's functionalities by switching between hardware and software components. Results show that our solution brings flexibility, accuracy, and fast alternative evaluation, as compared with RTL solutions, in the development and design of dynamically reconfigurable embedded systems.
Comparison of 4 numerical solvers for stiff and hybrid systems simulation

Numerical simulation of stiff and hybrid systems is widely used in various engineering domains. Numerical solvers, originally designed for purely continuous problems, are not sufficient for these systems. Modern simulation environments provide necessary modifications and extensions to solve the problem. The implementation details of solvers and run time systems greatly affect the performance of simulations regarding accuracy, velocity of simulation, compactness of results, and efficiency. Since no all-powerful solver exists, we assess four popular solvers (DASSL, LSODAR, DOPRI5, RADAU IIA), included in the all-purpose simulator Dymola® for different problems with continuous, stiff, and hybrid behavior. Key traits, including the number of steps, accuracy, CPU time and the event handling capability, are examined and advice for solver selection is given.