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This study evaluated cellulose nanofibers from bolaina blanca wood (Guazuma crinita) obtained at different heights of the longitudinal axis of the shaft of trees from a three-and-a-half-year-old plantation. The wood was subjected to pulping, bleaching and subsequent mechanical milling using a Changsha Samy XYQM-2L planetary ball mill to obtain cellulose nanofibers. The product was characterised using analytical techniques: scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy. Additionally, the degree of polymerisation was determined. The effect of longitudinal position on cellulose nanofibers characteristics was evaluated by comparing means using ANOVA and Kruskal–Wallis statistical tests. The yield of cellulose nanofibers production from the high, middle and basal sections was 32,1 %, 33,6 % and 31 %, respectively. The obtained cellulose nanofibers exhibited a significantly larger diameter for the high zone (84 nm) compared with the middle (75 nm) and basal (69 nm) zones; the length remained above the micrometre range. With respect to degree of polymerisation, a decrease was evidenced with respect to the increase in shaft height; the basal zone exhibited a degree of polymerisation of 300, a significantly higher value than the middle and high zones, which exhibited degree of polymerisation of 249 and 211, respectively. The product showed typical cellulose type I polymorphism and crystallinity indexes of 76 %, 93 % and 96 % for the high, middle and basal sections, respectively. Regarding the thermostability of cellulose nanofibers, the maximum degradation rate of cellulose nanofibers occurred between 335 °C and 341 °C, with cellulose nanofibers from the basal area being the most stable. The adsorption of the methylene blue dye on cellulose nanofibers was evaluated; an efficiency > 60 % was found., Este estudio evaluó nanofibras de celulosa de madera de bolaina blanca (Guazuma crinita) obtenidas a diferentes alturas del eje longitudinal del fuste de árboles de una plantación de tres años y medio. La madera fue sometida a despulpado, blanqueo y posterior molienda mecánica utilizando un molino planetario de bolas Changsha Samy XYQM-2L para obtener nanofibras de celulosa. El producto se caracterizó mediante técnicas analíticas: microscopía electrónica de barrido, difracción de rayos X, análisis termogravimétrico, espectroscopia infrarroja por transformada de Fourier, espectroscopia ultravioleta-visible. Además se determinó el grado de polimerización. El efecto de la posición longitudinal sobre las características de las nanofibras de celulosa se evaluó comparando medias utilizando las pruebas estadísticas ANOVA y Kruskal-Wallis. El rendimiento de la producción de nanofibras de celulosa de las secciones alta, media y basal fue de 32,1 %, 33,6 % y 31 %, respectivamente. Las nanofibras de celulosa obtenidas exhibieron un diámetro significativamente mayor para la zona alta (84 nm) en comparación con las zonas media (75 nm) y basal (69 nm); la longitud se mantuvo por encima del rango micrométrico. Con respecto al grado de polimerización, se evidenció una disminución con respecto al aumento de la altura del eje; la zona basal exhibió un grado de polimerización de 300, un valor significativamente más alto que las zonas media y alta, que exhibieron un grado de polimerización de 249 y 211, respectivamente. El producto presentó polimorfismo típico de celulosa tipo I e índices de cristalinidad de 76 %, 93 % y 96 % para las secciones alta, media y basal, respectivamente. En cuanto a la termoestabilidad de las nanofibras de celulosa, la tasa máxima de degradación de las nanofibras de celulosa se produjo entre 335 °C y 341 °C, siendo las nanofibras de celulosa de la zona basal las más estables. Se evaluó la adsorción del colorante azul de metileno sobre nanofibras de celulosa

This study evaluated cellulose nanofibers from bolaina blanca wood (Guazuma crinita) obtained at different heights of the longitudinal axis of the shaft of trees from a three-and-a-half-year-old plantation. The wood was subjected to pulping, bleaching and subsequent mechanical milling using a Changsha Samy XYQM-2L planetary ball mill to obtain cellulose nanofibers. The product was characterised using analytical techniques: scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy. Additionally, the degree of polymerisation was determined. The effect of longitudinal position on cellulose nanofibers characteristics was evaluated by comparing means using ANOVA and Kruskal–Wallis statistical tests. The yield of cellulose nanofibers production from the high, middle and basal sections was 32,1 %, 33,6 % and 31 %, respectively. The obtained cellulose nanofibers exhibited a significantly larger diameter for the high zone (84 nm) compared with the middle (75 nm) and basal (69 nm) zones; the length remained above the micrometre range. With respect to degree of polymerisation, a decrease was evidenced with respect to the increase in shaft height; the basal zone exhibited a degree of polymerisation of 300, a significantly higher value than the middle and high zones, which exhibited degree of polymerisation of 249 and 211, respectively. The product showed typical cellulose type I polymorphism and crystallinity indexes of 76 %, 93 % and 96 % for the high, middle and basal sections, respectively. Regarding the thermostability of cellulose nanofibers, the maximum degradation rate of cellulose nanofibers occurred between 335 °C and 341 °C, with cellulose nanofibers from the basal area being the most stable. The adsorption of the methylene blue dye on cellulose nanofibers was evaluated; an efficiency > 60 % was found., Este estudio evaluó nanofibras de celulosa de madera de bolaina blanca (Guazuma crinita) obtenidas a diferentes alturas del eje longitudinal del fuste de árboles de una plantación de tres años y medio. La madera fue sometida a despulpado, blanqueo y posterior molienda mecánica utilizando un molino planetario de bolas Changsha Samy XYQM-2L para obtener nanofibras de celulosa. El producto se caracterizó mediante técnicas analíticas: microscopía electrónica de barrido, difracción de rayos X, análisis termogravimétrico, espectroscopia infrarroja por transformada de Fourier, espectroscopia ultravioleta-visible. Además se determinó el grado de polimerización. El efecto de la posición longitudinal sobre las características de las nanofibras de celulosa se evaluó comparando medias utilizando las pruebas estadísticas ANOVA y Kruskal-Wallis. El rendimiento de la producción de nanofibras de celulosa de las secciones alta, media y basal fue de 32,1 %, 33,6 % y 31 %, respectivamente. Las nanofibras de celulosa obtenidas exhibieron un diámetro significativamente mayor para la zona alta (84 nm) en comparación con las zonas media (75 nm) y basal (69 nm); la longitud se mantuvo por encima del rango micrométrico. Con respecto al grado de polimerización, se evidenció una disminución con respecto al aumento de la altura del eje; la zona basal exhibió un grado de polimerización de 300, un valor significativamente más alto que las zonas media y alta, que exhibieron un grado de polimerización de 249 y 211, respectivamente. El producto presentó polimorfismo típico de celulosa tipo I e índices de cristalinidad de 76 %, 93 % y 96 % para las secciones alta, media y basal, respectivamente. En cuanto a la termoestabilidad de las nanofibras de celulosa, la tasa máxima de degradación de las nanofibras de celulosa se produjo entre 335 °C y 341 °C, siendo las nanofibras de celulosa de la zona basal las más estables. Se evaluó la adsorción del colorante azul de metileno sobre nanofibras de celulosa

In this paper, the energy and exergy performance of a vapour-compression refrigeration cycle of a water dispenser unit has been analyzed theoretically using different refrigerants as possible alternative substitutes to R134a. The selected low ?Global Warming Potential (GWP) ? refrigerants are: HydroFluoroOlefins (HFO) R1234yf and R1234ze(E), HydroCarbons (HC) R290 and R600a, and HydroFluoroCarbon (HFC) R152a. The process was evaluated based on the evaporator and condenser temperatures, which range between -10 and 5?C and between 30 and 45?C, respectively. The theoretical model based on the first and second laws of thermodynamics has been developed using the Matlab environment. The performances of the vapor compression cycle are discussed in terms of coefficient of performance, exergy destruction and exergy efficiency. The results show that the maximum COP achieved is 5.12 and 5.10 for R152a and R600a respectively, the highest total exergy destruction is about 82.82 W for R290, the highest exergy efficiency is about 55.12% for R600a., Communication présentée lors du congrès international tenu conjointement par Canadian Society for Mechanical Engineering (CSME) et Computational Fluid Dynamics Society of Canada (CFD Canada), à l’Université de Sherbrooke (Québec), du 28 au 31 mai 2023.

FP8 formats are gaining popularity to boost the computational efficiency for training and inference of large deep learning models. Their main challenge is that a careful choice of scaling is needed to prevent degradation due to the reduced dynamic range compared to higher-precision formats. Although there exists ample literature about selecting such scalings for INT formats, this critical aspect has yet to be addressed for FP8. This paper presents a methodology to select the scalings for FP8 linear layers, based on dynamically updating per-tensor scales for the weights, gradients and activations. We apply this methodology to train and validate large language models of the type of GPT and Llama 2 using FP8, for model sizes ranging from 111M to 70B. To facilitate the understanding of the FP8 dynamics, our results are accompanied by plots of the per-tensor scale distribution for weights, activations and gradients during both training and inference.

El projecte consisteix en la creació d'un entorn virtual, a partir de les màquines vulnerables disponibles de Metasploitable, el qual comptarà amb diferents màquines vulnerables. La finalitat és exposar les vulnerabilitats trobades en el projecte de Metasploitable, el qual compta amb diferents màquines vulnerables, i es realitzarà explotació d'aquestes mostrant les possibles vies d'atac amb les quals un ciberdelinqüent pot beneficiar-se. Finalment, s'exposaran els resultats en l'informe tècnic. Aquest document explora, també, la matriu de Mitre[1], el qual és una base de coneixements, contínuament actualitzada des del 2013, que mostra els elements tàctics, tècnics, subtècniques, de procediment i d'altres que intervenen en el desplegament d'un atac des de la perspectiva d'un atacant. Per cada màquina identificada s'estudiaran les tècniques, tàctiques i procediments aplicats amb relació al framework de Mitre Att&ck, on s'estudiarà la utilitat que podria tenir en l'àmbit dels Blue Teams i en els Red Teams., The project consists of the creation of a virtual environment, from the available vulnerable machines of Metasploitable, which will have different vulnerable machines. The purpose is to expose the vulnerabilities found in the Metasploitable project, which has different vulnerable machines, and will exploit them showing the possible avenues of attack with which a cybercriminal can benefit. Finally, the results will be presented in the technical report. This document also explores the Miter matrix [1], which is a knowledge base, continuously updated since 2013, which shows the tactical, technical, sub-technical, procedural and other elements involved in the deployment of Miter. 'an attack from the perspective of an attacker. For each machine identified, the techniques, tactics and procedures applied in relation to the Miter Att & ck framework will be studied, where the usefulness it could have in the field of Blue Teams and Red Teams will be studied., El proyecto consiste en la creación de un entorno virtual, a partir de las máquinas vulnerables disponibles de Metasploitable, que contará con diferentes máquinas vulnerables. La finalidad es exponer las vulnerabilidades encontradas en el proyecto de Metasploitable, que cuenta con diferentes máquinas vulnerables, y se realizará explotación de éstas mostrando las posibles vías de ataque con las que un ciberdelincuente puede beneficiarse. Por último, se expondrán los resultados en el informe técnico. Este documento explora, también, la matriz de Mitre[1], que es una base de conocimientos, continuamente actualizada desde 2013, que muestra los elementos tácticos, técnicos, subtécnicas, de procedimiento y otros que intervienen en el despliegue de un ataque desde la perspectiva de un atacante. Por cada máquina identificada se estudiarán las técnicas, tácticas y procedimientos aplicados en relación con el framework de Mitre Att&ck, donde se estudiará la utilidad que podría tener en el ámbito de los Blue Teams y en los Red Teams.

System identification, also known as learning forward models, transfer functions, system dynamics, etc., has a long tradition both in science and engineering in different fields. Particularly, it is a recurring theme in Reinforcement Learning research, where forward models approximate the state transition function of a Markov Decision Process by learning a mapping function from current state and action to the next state. This problem is commonly defined as a Supervised Learning problem in a direct way. This common approach faces several difficulties due to the inherent complexities of the dynamics to learn, for example, delayed effects, high non-linearity, non-stationarity, partial observability and, more important, error accumulation when using bootstrapped predictions (predictions based on past predictions), over large time horizons. Here we explore the use of Reinforcement Learning in this problem. We elaborate on why and how this problem fits naturally and sound as a Reinforcement Learning problem, and present some experimental results that demonstrate RL is a promising technique to solve these kind of problems., Comment: Accepted in Neurips Deep Reinforcement Learning Workshop 2022: https://openreview.net/forum?id=fGcbpWQIJZV

[EN] Translanguaging is a new approach to language use, bilingual acquisition, and bilingual education that sees all acquired languages (or those being acquired) as components of one bi/multilingual repertoire (García & Wei, 2014). However, discussions of specific pedagogical applications of translingualism have remained limited and speculative (Gervers, 2018; Matsuda, 2014). Hence, it is still unclear how such pedagogies would address the needs of bi/multilingual student writers. Based on the need to further understand the use of translanguaging in the classroom, the present article explores the translingual practices and attitudes of students in a Spanish undergraduate writing class. Participants were 9 undergraduate students from a university in the United States. Data collection involved an online questionnaire, individual interviews —which focused on attitudes towards translanguaging— and the student’s submission of their final project, which allowed the researchers to observe whether students reflected the translanguaging practices in the project. Results from online questionnaire and interviews suggest that students can better focus on the message they want to convey without linguistic pressure that forces them to use one language only. Additionally, pairing students for collaborative writing enhanced their overall drafting development. Results from the final projects reflect that students tend to not reflect translanguaging in their final version.

[EN] Translanguaging is a new approach to language use, bilingual acquisition, and bilingual education that sees all acquired languages (or those being acquired) as components of one bi/multilingual repertoire (García & Wei, 2014). However, discussions of specific pedagogical applications of translingualism have remained limited and speculative (Gervers, 2018; Matsuda, 2014). Hence, it is still unclear how such pedagogies would address the needs of bi/multilingual student writers. Based on the need to further understand the use of translanguaging in the classroom, the present article explores the translingual practices and attitudes of students in a Spanish undergraduate writing class. Participants were 9 undergraduate students from a university in the United States. Data collection involved an online questionnaire, individual interviews —which focused on attitudes towards translanguaging— and the student’s submission of their final project, which allowed the researchers to observe whether students reflected the translanguaging practices in the project. Results from online questionnaire and interviews suggest that students can better focus on the message they want to convey without linguistic pressure that forces them to use one language only. Additionally, pairing students for collaborative writing enhanced their overall drafting development. Results from the final projects reflect that students tend to not reflect translanguaging in their final version.

[EN] Translanguaging is a new approach to language use, bilingual acquisition, and bilingual education that sees all acquired languages (or those being acquired) as components of one bi/multilingual repertoire (García & Wei, 2014). However, discussions of specific pedagogical applications of translingualism have remained limited and speculative (Gervers, 2018; Matsuda, 2014). Hence, it is still unclear how such pedagogies would address the needs of bi/multilingual student writers. Based on the need to further understand the use of translanguaging in the classroom, the present article explores the translingual practices and attitudes of students in a Spanish undergraduate writing class. Participants were 9 undergraduate students from a university in the United States. Data collection involved an online questionnaire, individual interviews —which focused on attitudes towards translanguaging— and the student’s submission of their final project, which allowed the researchers to observe whether students reflected the translanguaging practices in the project. Results from online questionnaire and interviews suggest that students can better focus on the message they want to convey without linguistic pressure that forces them to use one language only. Additionally, pairing students for collaborative writing enhanced their overall drafting development. Results from the final projects reflect that students tend to not reflect translanguaging in their final version.

Effective training of today's large language models (LLMs) depends on large batches and long sequences for throughput and accuracy. To handle variable-length sequences on hardware accelerators, it is common practice to introduce padding tokens, so that all sequences in a batch have the same length. We show in this paper that the variation in sequence lengths in common NLP datasets is such that up to 50% of all tokens can be padding. In less common, but not extreme, cases (e.g. GLUE-cola with sequence length 128), the ratio is up to 89%. Existing methods to address the resulting inefficiency are complicated by the need to avoid cross-contamination in self-attention, by a reduction in accuracy when sequence ordering information is lost, or by customized kernel implementations only valid for specific accelerators. This paper introduces a new formalization of sequence packing in the context of the well-studied bin packing problem, and presents new algorithms based on this formulation which, for example, confer a 2x speedup for phase 2 pre-training in BERT. We show how existing models can be adapted to ensure mathematical equivalence between the original and packed models, meaning that packed models can be trained with existing pre-training and fine-tuning practices., Comment: Significantly new version with different authors and much more content. Much larger variety in experiments and exhaustive SOTA analysis

We propose finite-volume schemes for the Cahn-Hilliard equation which unconditionally and discretely preserve the boundedness of the phase field and the dissipation of the free energy. Our numerical framework is applicable to a variety of free-energy potentials, including Ginzburg-Landau and Flory-Huggins, to general wetting boundary conditions, and to degenerate mobilities. Its central thrust is the upwind methodology, which we combine with a semi-implicit formulation for the free-energy terms based on the classical convex-splitting approach. The extension of the schemes to an arbitrary number of dimensions is straightforward thanks to their dimensionally split nature, which allows to efficiently solve higher-dimensional problems with a simple parallelisation. The numerical schemes are validated and tested through a variety of examples, in different dimensions, and with various contact angles between droplets and substrates.

We assess the benefit of including an image inpainting filter before passing damaged images into a classification neural network. For this we employ a modified Cahn-Hilliard equation as an image inpainting filter, which is solved via a finite volume scheme with reduced computational cost and adequate properties for energy stability and boundedness. The benchmark dataset employed here is MNIST, which consists of binary images of handwritten digits and is a standard dataset to validate image-processing methodologies. We train a neural network based of dense layers with the training set of MNIST, and subsequently we contaminate the test set with damage of different types and intensities. We then compare the prediction accuracy of the neural network with and without applying the Cahn-Hilliard filter to the damaged images test. Our results quantify the significant improvement of damaged-image prediction due to applying the Cahn-Hilliard filter, which for specific damages can increase up to 50% and is in general advantageous for low to moderate damage., Comment: An interactive jupyter notebook with the code of this work is available at https://github.com/sergiopperez/Image_Inpainting. The MNIST dataset employed in this work can be downloaded from http://yann.lecun.com/exdb/mnist

We propose high-order well-balanced finite-volume schemes for a broad class of hydrodynamic systems with attractive-repulsive interaction forces and linear and nonlinear damping. Our schemes are suitable for free energies containing convolutions of an interaction potential with the density, which are essential for applications such as the Keller-Segel model, more general Euler-Poisson systems, or dynamic-density functional theory. Our schemes are also equipped with a nonnegative-density reconstruction which allows for vacuum regions during the simulation. We provide several prototypical examples from relevant applications highlighting the benefit of our algorithms elucidate also some of our analytical results.

We introduce a finite-volume numerical scheme for solving stochastic gradient-flow equations. Such equations are of crucial importance within the framework of fluctuating hydrodynamics and dynamic density functional theory. Our proposed scheme deals with general free-energy functionals, including, for instance, external fields or interaction potentials. This allows us to simulate a range of physical phenomena where thermal fluctuations play a crucial role, such as nucleation and other energy-barrier crossing transitions. A positivity-preserving algorithm for the density is derived based on a hybrid space discretization of the deterministic and the stochastic terms and different implicit and explicit time integrators. We show through numerous applications that not only our scheme is able to accurately reproduce the statistical properties (structure factor and correlations) of the physical system, but, because of the multiplicative noise, it allows us to simulate energy barrier crossing dynamics, which cannot be captured by mean-field approaches.

Well balanced and free energy dissipative first- and second-order accurate finite volume schemes are proposed for a general class of hydrodynamic systems with linear and nonlinear damping. The natural Liapunov functional of the system, given by its free energy, allows for a characterization of the stationary states by its variation. An analog property at the discrete level enables us to preserve stationary states at machine precision while keeping the dissipation of the discrete free energy. These schemes allow for analysing accurately the stability properties of stationary states in challeging problems such as: phase transitions in collective behavior, generalized Euler-Poisson systems in chemotaxis and astrophysics, and models in dynamic density functional theories; having done a careful validation in a battery of relevant test cases., Comment: Videos from the simulations of this work are available at https://figshare.com/projects/Well-balanced_finite_volume_schemes_for_hydrodynamic_equations_with_general_free_energy/60122

We give a detailed review of two algorithms that solve the minimization case of the assignment problem. The Bertsekas' auction algorithm and the Goldberg & Kennedy algorithm. We will show that these algorithms are equivalent in the sense that both perform equivalent steps in the same order. We also present experimental results comparing the performance of three algorithms for the assignment problem. They show the auction algorithm performs and scales better in practice than algorithms that are harder to implement but have better theoretical time complexity., Comment: 21 pages, 6 figures

This paper presents the design and characterization of a new analog voltage follower for low-voltage applications. The main idea is based on the “Flipped” Voltage Follower and the use of the quasi-floating gate technique for achieving class AB operation. A test cell was simulated and fabricated using a 0,5 μm CMOS technology. When the proposed circuit is supplied with VDD = 1,5 V, it presents a power consumption of only 413 μW. Measurement and experimental results show a gain bandwidth product of 10 MHz and a total harmonic distortion of 1,12 % at 1 MHz., En este trabajo se presenta el diseño y caracterización de un nuevo seguidor de voltaje analógico para aplicaciones de bajo voltaje. La idea principal aquí desarrollada, está basada en el Seguidor de Voltaje “Volteado” y el uso de técnicas de compuerta casiflotante para lograr un funcionamiento de clase AB. Usando una tecnología CMOS de 0.5 μm, se simuló y se fabricó una celda de prueba. Cuando el circuito propuesto se alimenta con VDD = 1,5 V, este presenta un consumo de potencia de tan solo 413 μW. Las mediciones y los resultados experimentales muestran un producto ganancia-ancho de banda de 10 MHz y una distorsión harmónica total de 1,12 % a 1 MHz.

[EN] New emerging technologies have proven their efficacy in aiding people in their rehabilitation. The tests that are usually used to evaluate usability (in general) or user satisfaction (in particular) of this technology are not specifically focused on virtual rehabilitation and patients. The objective of this contribution is to present and evaluate the USEQ (User Satisfaction Evaluation Questionnaire). The USEQ is a questionnaire that is designed to properly evaluate the satisfaction of the user (which constitutes part of usability) in virtual rehabilitation systems. Forty patients with balance disorders completed the USEQ after their first session with ABAR (Active Balance Rehabilitation), which is a virtual rehabilitation system that is designed for the rehabilitation of balance disorders. Internal consistency analysis and exploratory factor analysis were carried out to identify the factor structure of the USEQ. The six items of USEQ were significantly associated with each other, and the Cronbach alpha coefficient for the questionnaire was 0.716. In an analysis of the principal components, a one-factor solution was considered to be appropriate. The findings of the study suggest that the USEQ is a reliable questionnaire with adequate internal consistency. With regard to patient perception, the patients found the USEQ to be an easy-to-understand questionnaire with a convenient number of questions.

[EN] New emerging technologies have proven their efficacy in aiding people in their rehabilitation. The tests that are usually used to evaluate usability (in general) or user satisfaction (in particular) of this technology are not specifically focused on virtual rehabilitation and patients. The objective of this contribution is to present and evaluate the USEQ (User Satisfaction Evaluation Questionnaire). The USEQ is a questionnaire that is designed to properly evaluate the satisfaction of the user (which constitutes part of usability) in virtual rehabilitation systems. Forty patients with balance disorders completed the USEQ after their first session with ABAR (Active Balance Rehabilitation), which is a virtual rehabilitation system that is designed for the rehabilitation of balance disorders. Internal consistency analysis and exploratory factor analysis were carried out to identify the factor structure of the USEQ. The six items of USEQ were significantly associated with each other, and the Cronbach alpha coefficient for the questionnaire was 0.716. In an analysis of the principal components, a one-factor solution was considered to be appropriate. The findings of the study suggest that the USEQ is a reliable questionnaire with adequate internal consistency. With regard to patient perception, the patients found the USEQ to be an easy-to-understand questionnaire with a convenient number of questions.

[EN] Objectives: Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by motor clinical alterations among others. Postural problems have serious consequences for patients, not only limiting their daily life but also increasing some risks, like the risk of fall. Inadequate postural control and postural instability is a major problem in PD patients. A Virtual Motor Rehabilitation System (VMR) has been tested in patients with PD in the intervention period. Our pur-pose was to analyze the evolution of the spatial postural control during the intervention period, to see if there are any changes caused precisely by this intervention. Methods: Ten people with PD carried out 15 virtual rehabilitation sessions. We tested a groundbreaking system based on Virtual Motor Rehabilitation in two periods of time (baseline evaluation and final evaluation). In the training sessions, the participants performed a customizable treatment using a low-cost system, the Active Balance Rehabilitation system (ABAR). We stored the pressure performed by the participants every five hundredths of a second, and we analyzed the patients' pressure when they maintained their body on the left, on the right, and in the center in sitting position. Our system was able to measure postural control in every patient in each of the virtual rehabilitation sessions. Results: There are no significant differences in the performance of postural control in any of the positions evaluated throughout the sessions. Moreover, the results show a trend to an improvement in all positions. This improvement is especially remarkable in the left/right positions, which are the most important positions in order to avoid problems such as the risk of fall. With regard to the suitability of the ABAR system, we have found outstanding results in enjoyment, success, clarity, and helpfulness. Conclusions: Although PD is a progressive neurodegenerative disorder, the results demonstrate that patients with PD ma

In this paper, we present an automated feature engineering based approach to dramatically reduce false positives in fraud prediction. False positives plague the fraud prediction industry. It is estimated that only 1 in 5 declared as fraud are actually fraud and roughly 1 in every 6 customers have had a valid transaction declined in the past year. To address this problem, we use the Deep Feature Synthesis algorithm to automatically derive behavioral features based on the historical data of the card associated with a transaction. We generate 237 features (>100 behavioral patterns) for each transaction, and use a random forest to learn a classifier. We tested our machine learning model on data from a large multinational bank and compared it to their existing solution. On an unseen data of 1.852 million transactions, we were able to reduce the false positives by 54% and provide a savings of 190K euros. We also assess how to deploy this solution, and whether it necessitates streaming computation for real time scoring. We found that our solution can maintain similar benefits even when historical features are computed once every 7 days.

This survey summarizes and illustrates the main qualitative properties of hydrodynamics models for collective behavior. These models include a velocity consensus term together with attractive-repulsive potentials leading to non-trivial flock profiles. The connection between the underlying particle systems to the swarming hydrodynamic equations is performed through kinetic theory modelling arguments. We focus on Lagrangian schemes for the hydrodynamic systems showing the different qualitative behavior of the systems and its capability of keeping properties of the original particle models. We illustrate known results concerning large time profiles and blow-up in finite time of the hydrodynamic systems to validate the numerical scheme. We finally explore unknown situations making use of the numerical scheme showcasing a number of conjectures based on the numerical results., Comment: 36 pages, 67 figures

[EN] Introduction: This article is part of the Focus Theme of Methods of Information in Medicine on "New Methodologies for Patients Rehabilitation". Objectives: For Guillain-Barre patients, motor rehabilitation programs are helpful at the onset to prevent the complications of paralysis and in cases of persistent motor impairment. Traditional motor rehabilitation programs may be tedious and monotonous, resulting in low adherence to the treatments. A Virtual Motor Rehabilitation system has been tested in Guillain-Barre patients to increase patient adherence and to improve clinical results. Methods: Two people with Guillain-Barre performed 20 rehabilitation sessions. We tested a novel system based on Motor Virtual Rehabilitation in three periods of time (baseline evaluation, final evaluation, and follow-up. In the training program, the participants carried out a specific treatment using the Active Balance Rehabilitation system (ABAR). The system is composed of customizable virtual games to perform static and dynamic balance rehabilitation. Results: Significant improvements in clinical results were obtained by both participants, with significant results in the static balance clinical test of the Anterior Reach test in the standing position and unipedal stance time. Other significant results were found in dynamic balance clinical tests in the Berg Balance Scale test and the 30-second Sit-to-Stand test. With regard to acceptance of the system, both patients enjoyed the experience, and both patients thought that this system was helpful for their rehabilitation. Conclusions: The results show that Virtual Motor Rehabilitation for Guillain-Barre patients provides clinical improvements in an entertaining way.

[EN] Introduction: This article is part of the Focus Theme of Methods of Information in Medicine on "New Methodologies for Patients Rehabilitation". Objectives: For Guillain-Barre patients, motor rehabilitation programs are helpful at the onset to prevent the complications of paralysis and in cases of persistent motor impairment. Traditional motor rehabilitation programs may be tedious and monotonous, resulting in low adherence to the treatments. A Virtual Motor Rehabilitation system has been tested in Guillain-Barre patients to increase patient adherence and to improve clinical results. Methods: Two people with Guillain-Barre performed 20 rehabilitation sessions. We tested a novel system based on Motor Virtual Rehabilitation in three periods of time (baseline evaluation, final evaluation, and follow-up. In the training program, the participants carried out a specific treatment using the Active Balance Rehabilitation system (ABAR). The system is composed of customizable virtual games to perform static and dynamic balance rehabilitation. Results: Significant improvements in clinical results were obtained by both participants, with significant results in the static balance clinical test of the Anterior Reach test in the standing position and unipedal stance time. Other significant results were found in dynamic balance clinical tests in the Berg Balance Scale test and the 30-second Sit-to-Stand test. With regard to acceptance of the system, both patients enjoyed the experience, and both patients thought that this system was helpful for their rehabilitation. Conclusions: The results show that Virtual Motor Rehabilitation for Guillain-Barre patients provides clinical improvements in an entertaining way.

In this work, the calculation modules for the desulfurizers of the hydrodesulfurization section of the ammonia plant of the Morón Petrochemical Complex, Carabobo, Venezuela, are developed. For the development of the calculation modules, the analysis of the various technologies used in the natural gas hydrodesulfurization stage was carried out, the mathematical models corresponding to the desulfurizers were established, these modules were developed in the Java programming language, they were designed a graphical interface of interaction between the user and the simulator, in the same language as the modules and finally the validation of the calculation modules developed for the simulator was carried out comparing the results obtained with those generated by the commercial simulator SUPER PRO DESIGNER 4.7 . Based on the results, it can be concluded that the Dubinin-Radushkevic mathematical model used to represent the physical adsorption of H2 S and in the development of the calculation module of the desulfurization stage, was acceptable, because of the low registered deviation percentages compared to the results obtained by the commercial simulator, lower than 5%., En este trabajo se desarrollan los módulos de cálculo para los desulfuradores de la sección de hidrodesulfuración de la planta de amoníaco del Complejo Petroquímico Morón, Carabobo, Venezuela. Para el desarrollo de los módulos de cálculo se hizo el análisis de las diversas tecnologías que se emplean en la etapa de hidrodesulfuración del gas natural, se establecieron los modelos matemáticos correspondientes a los desulfuradores, se desarrollaron dichos módulos en lenguaje de programación Java, se diseñó una interfaz gráfica de interacción entre el usuario y el simulador, en el mismo lenguaje que los módulos y por último se realizó la validación de los módulos de cálculo desarrollados para el simulador comparando los resultados obtenidos con los generados por el simulador comercial SUPER PRO DESIGNER 4.7. En base a los resultados se puede concluir que, el modelo matemático de Dubinin-Radushkevic utilizado para representar la adsorción de carácter física del H2 S y en el desarrollo del módulo de cálculo de la etapa de desulfuración, resultó aceptable, en razón a los bajos porcentajes de desviación registrados en comparación con los resultados obtenidos por el simulador comercia, inferiores a un 5%.

The kinetics of the esterification reaction that occurs in a reactor per load, used in the production of polyester, installed in a chemical plant in the Valencia industrial zone of Venezuela was studied. With this information, and that of a set of variables influencing the process such as: temperature, acidity index, viscosity; the thermal evaluation of the reactor was carried out. Different batches elaborated in the studied reactor were followed, where temperature data of the heating system, the condensers, the cooling system and the reaction mixture were taken during all the stages of the process. At the same time, the variation in the properties of the resin during the process was measured, taking samples of the product in each stage of the process, determining: acidity index, viscosity and specific gravity. A laboratory-level study was carried out with equipment and conditions similar to the plant process, modifying the original molar ratio of the reactants and the process temperature, in order to study their influence on the kinetics, by means of consecutive measurements of the acidity index of the mixture. in the reactorExperimental throughout the process.At the process conditions, the synthesis reaction of the polyester resin has a velocity constant of 0.00031461 kg2 / eq2. s, the heats exchanged are between: 17000-7000 J / s heating stage,Between 7000-5000 J / s stage of heating with reaction, between 5400-4500J / s stage of atmospheric esterification and between 4500-2200J / s stage of vacuum esterification., Se estudió la cinética de la reacción de esterificación que ocurre en un reactor por carga, empleado en la producción de poliéster, instalado en una planta química en la zona industrial Valencia de Venezuela. Con esta información, y la de un conjunto de variables influyentes al proceso como: temperatura, índice de acidez, viscosidad; se realizó la evaluación térmica del reactor. Se hizo un seguimiento a distintos lotes elaborados en el reactor estudiado, donde se tomaron datos de temperaturas del sistema de calentamiento, de los condensadores, del sistema de enfriamiento y de la mezcla de reacción, durante todas las etapas del proceso. Paralelamente se midió la variación en las propiedades de la resina durante el proceso, tomando muestras de producto en cada etapa del mismo, determinándose: índice de acidez, viscosidad y gravedad específica. Se realizó un estudio a nivel de laboratorio con equipos y condiciones semejantes al proceso en planta, modificando la relación molar original de los reactantes y la temperatura de proceso, para estudiar su influencia en la cinética, mediante mediciones consecutivas del índice de acidez de la mezcla en el reactor Experimental a lo largo del proceso. A las condiciones de proceso, la reacción de síntesis de la resina de poliéster presenta una constante de velocidad de 0,00031461 kg2 /eq2. s, los calores intercambiados están comprendidos entre: 17000-7000 J/s etapa de calentamiento, Entre 7000-5000 J/s etapa de calentamiento con reacción, entre 5400-4500J/s etapa de esterificación atmosférica y entre 4500-2200J/s etapa de esterificación al vacío.

The material characterization toolbox has recently experienced a number of parallel revolutionary advances, foreshadowing a time in the near future when material scientists can quantify material structure evolution across spatial and temporal space simultaneously. This will provide insight to reaction dynamics in four-dimensions, spanning multiple orders of magnitude in both temporal and spatial space. This study presents the authors’ viewpoint on the material characterization field, reviewing its recent past, evaluating its present capabilities, and proposing directions for its future development. Electron microscopy; atom probe tomography; x-ray, neutron and electron tomography; serial sectioning tomography; and diffraction-based analysis methods are reviewed, and opportunities for their future development are highlighted. Advances in surface probe microscopy have been reviewed recently and, therefore, are not included [D.A. Bonnell et al.: Rev. Modern Phys. in Review]. In this study particular attention is paid to studies that have pioneered the synergetic use of multiple techniques to provide complementary views of a single structure or process; several of these studies represent the state-of-the-art in characterization and suggest a trajectory for the continued development of the field. Based on this review, a set of grand challenges for characterization science is identified, including suggestions for instrumentation advances, scientific problems in microstructure analysis, and complex structure evolution problems involving material damage. The future of microstructural characterization is proposed to be one not only where individual techniques are pushed to their limits, but where the community devises strategies of technique synergy to address complex multiscale problems in materials science and engineering., United States. Dept. of Energy. Office of Basic Energy Sciences (Council of Materials Science and Engineering), National Science Foundation (U.S.) (Grant DMR-0855402)

Mitochondrial Ca(2+) uptake via the uniporter is central to cell metabolism, signaling, and survival. Recent studies identified MCU as the uniporter's likely pore and MICU1, an EF-hand protein, as its critical regulator. How this complex decodes dynamic cytoplasmic [Ca(2+)] ([Ca(2+)]c) signals, to tune out small [Ca(2+)]c increases yet permit pulse transmission, remains unknown. We report that loss of MICU1 in mouse liver and cultured cells causes mitochondrial Ca(2+) accumulation during small [Ca(2+)]c elevations but an attenuated response to agonist-induced [Ca(2+)]c pulses. The latter reflects loss of positive cooperativity, likely via the EF-hands. MICU1 faces the intermembrane space and responds to [Ca(2+)]c changes. Prolonged MICU1 loss leads to an adaptive increase in matrix Ca(2+) binding, yet cells show impaired oxidative metabolism and sensitization to Ca(2+) overload. Collectively, the data indicate that MICU1 senses the [Ca(2+)]c to establish the uniporter's threshold and gain, thereby allowing mitochondria to properly decode different inputs.

The use of anonymity-based infrastructures and anonymisers is a plausible solution to mitigate privacy problems on the Internet. Tor (short for The onion router) is a popular low-latency anonymity system that can be installed as an end-user application on a wide range of operating systems to redirect the traffic through a series of anonymising proxy circuits. The construction of these circuits determines both the latency and the anonymity degree of the Tor anonymity system. While some circuit construction strategies lead to delays which are tolerated for activities like Web browsing, they can make the system vulnerable to linking attacks. We evaluate in this paper three classical strategies for the construction of Tor circuits, with respect to their de-anonymisation risk and latency performance. We then develop a new circuit selection algorithm that considerably reduces the success probability of linking attacks while keeping a good degree of performance. We finally conduct experiments on a real-world Tor deployment over PlanetLab. Our experimental results confirm the validity of our strategy and its performance increase for Web browsing., Comment: 34

Castellano: El objetivo principal de este proyecto es el de investigar, experimentar, desarrollar componentes y construir un prototipo demostrador que ilustre como desarrollar y albergar una aplicación en la nube (en concreto Azure de Microsoft) para que esta i) pueda ser accedida de forma segura mediante el uso de tecnologías de federación (Interidy IdP, InfoCards, SAML) con autenticación única (SSO Single Sign-On) entre todos los sistemas y aplicaciones, y ii) pueda incluir mecanismos de seguridad, como la firma electrónica, que también se ofrecen como servicio (TrustedX) y que pueden estar albergados también en la nube.

The SOAP (Study of Open Access Publishing) project has run a large-scale survey of the attitudes of researchers on, and the experiences with, open access publishing. Around forty thousands answers were collected across disciplines and around the world, showing an overwhelming support for the idea of open access, while highlighting funding and (perceived) quality as the main barriers to publishing in open access journals. This article serves as an introduction to the survey and presents this and other highlights from a preliminary analysis of the survey responses. To allow a maximal re-use of the information collected by this survey, the data are hereby released under a CC0 waiver, so to allow libraries, publishers, funding agencies and academics to further analyse risks and opportunities, drivers and barriers, in the transition to open access publishing., Comment: Data manual available at http://bit.ly/gI8nct Compressed CSV data file available at http://bit.ly/gSmm71 Alternative data formats: CSV http://bit.ly/ejuvKO XLS http://bit.ly/e6gE7o XLSX http://bit.ly/gTjyvy

The material characterization toolbox has recently experienced a number of parallel revolutionary advances, foreshadowing a time in the near future when material scientists can quantify material structure evolution across spatial and temporal space simultaneously. This will provide insight to reaction dynamics in four-dimensions, spanning multiple orders of magnitude in both temporal and spatial space. This study presents the authors' viewpoint on the material characterization field, reviewing its recent past, evaluating its present capabilities, and proposing directions for its future development. Electron microscopy; atom probe tomography; x-ray, neutron and electron tomography; serial sectioning tomography; and diffraction-based analysis methods are reviewed, and opportunities for their future development are highlighted. Advances in surface probe microscopy have been reviewed recently and, therefore, are not included [D.A. Bonnell et al.: Rev. Modern Phys. in Review]. In this study particular attention is paid to studies that have pioneered the synergetic use of multiple techniques to provide complementary views of a single structure or process; several of these studies represent the state-of-the-art in characterization and suggest a trajectory for the continued development of the field. Based on this review, a set of grand challenges for characterization science is identified, including suggestions for instrumentation advances, scientific problems in microstructure analysis, and complex structure evolution problems involving material damage. The future of microstructural characterization is proposed to be one not only where individual techniques are pushed to their limits, but where the community devises strategies of technique synergy to address complex multiscale problems in materials science and engineering.

The SOAP (Study of Open Access Publishing) project has compiled data on the present offer for open access publishing in online peer-reviewed journals. Starting from the Directory of Open Access Journals, several sources of data are considered, including inspection of journal web site and direct inquiries within the publishing industry. Several results are derived and discussed, together with their correlations: the number of open access journals and articles; their subject area; the starting date of open access journals; the size and business models of open access publishers; the licensing models; the presence of an impact factor; the uptake of hybrid open access., Comment: Submitted to PLoS ONE

Over the last few years there have been significant developments in the field of three-dimensional atom probe (3DAP) analysis. This article reviews some of the technical compromises that have led to different instrument designs and the recent improvements in performance. An instrument has now been developed, based around a novel reflectron configuration combining both energy compensation and focusing elements, that yields a large field of view and very high mass resolution. The use of laser pulsing in the 3DAP, together with developments in specimen preparation methods using a focused ion-beam instrument, have led to a significant widening in the range of materials science problems that can be addressed with the 3DAP. Recent studies of semiconductor materials and devices are described., info:eu-repo/semantics/published

El objetivo principal del trabajo consiste en la optimización de la geometría general de un tipo específico de aeronaves, los Flying Wings. Estas aeronaves difieren del concepto de avión actual, por la inexistencia de un cuerpo cilíndrico y de cola. Por este motivo, los Flying Wings reciben su nombre, ya que se asemejan a una única ala en vuelo. Para la optimización han sido utilizadas técnicas DFC (Dinámica de Fluidos Computacional), permitiendo simular diversas geometrías en diferentes condiciones de vuelo. Primero se explica el concepto e idea de los Flying Wing y las técnicas DFC. Incluyendo algunos conceptos de aerodinámica que facilitarán el entendimiento del trabajo. Para la simulación de cualquier geometría es necesario un proceso de creación, el cual está explicado detalladamente. La forma más conveniente y más lógica de optimizar un Flying Wing, consiste en la creación de varias geometrías diferentes, para escoger una como la geometría óptima. Así, posteriormente, se utiliza esta geometría optimizada, para aplicar cambios sobre ella, intentando mejorarla. Estos cambios consisten en variar el diedro y la flecha de la aeronave, así como añadir un winglet y redondear la forma de la geometría. Por último se analiza la geometría optimizada, para poder observar la distribución de presiones de la misma.