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The incidence of candidemia in healthcare centers is associated with high morbidity and mortality. Frequency varies significantly among regions, with some species being more prevalent than others in Latin America. In this study, 191 clinical Candida isolates were collected from a major hospital in Ecuador from January 2019 to February 2020 aiming to assess their prevalence and distribution. After data processing, 168 isolates characterized by the VITEK 2 system were subsequently identified by ITS sequencing. Results showed diverse Candida species distributions, with C. albicans and C. tropicalis being the most prevalent across different clinical sources. In hospitalized individuals, C. tropicalis (38%) and C. albicans (37%) were the most prevalent, followed by, C. parapsilosis (16%), C. glabrata (5%), and other non-Candida albicans (NCA) species (6%). Conversely, C. parapsilosis (48%), C. albicans (20%), and C. glabrata (14%), associated with candidemia, were the most common in blood and CSF. Additionally, uncommon NCA species such as C. haemulonii, C. kefyr, and C. pelliculosa were identified in Ecuador for the first time. Discrepancies in species identification were observed between the VITEK 2 system and ITS sequencing, coinciding at 85%. This highlights the need for ongoing surveillance and identification efforts in Ecuador's clinical and epidemiological settings. [ABSTRACT FROM AUTHOR]

Gender classification on normalized iris images has been previously attempted with varying degrees of success. In these previous studies, it has been shown that occlusion masks may introduce gender information; occlusion masks are used in iris recognition to remove non-iris elements. When, the goal is to classify the gender using exclusively the iris texture, the presence of gender information in the masks may result in apparently higher accuracy, thereby not reflecting the actual gender information present in the iris. However, no measures have been taken to eliminate this information while preserving as much iris information as possible. We propose a novel method to assess the gender information present in the iris more accurately by eliminating gender information in the masks. This consists of pairing iris with similar masks and different gender, generating a paired mask using the OR operator, and applying this mask to the iris. Additionally, we manually fix iris segmentation errors to study their impact on the gender classification. Our results show that occlusion masks can account for 6.92% of the gender classification accuracy on average. Therefore, works aiming to perform gender classification using the iris texture from normalized iris images should eliminate this correlation. [ABSTRACT FROM AUTHOR]

In this work, we design a control strategy to be applied in a port-Hamilton representation of a liquid-mirror telescope for an alt-azimuth configuration. Starting from a dynamical model for an alt-azimuth liquid-mirror telescope based on Lagrange mechanics, a transformation to the port-Hamilton form is made. Such a dynamical model is obtained by computing the kinetic and potential energy of the telescope and substituting them in the Euler–Lagrange equation of motion. Then, for the transformation to the port-Hamiltonian form, we obtain the relation between the Hamiltonian and the Lagrangian. The resulting open-loop model based on the Hamiltonian function is controlled using an extension of the interconnection and damping-assignment passivity-based control aiming for a robust and accurate steady behavior in the closed loop while tracking a star's position. For comparison purposes, two different control strategies are applied to the Lagrangian model, inverse-dynamics control and sliding mode super-twisting control. Since the light is collected by the principal mirror of the telescope while tracking a star, we make a description of the liquid mirror's behavior. The tracking star's position is described as a function of the observer's position and the star's coordinates as well as the date of observation. The simulations' results show that the port-Hamilton control has a good transitory and steady response as well as great accuracy competing with that of inverse-dynamics control but with greater robustness and no chattering drawback. [ABSTRACT FROM AUTHOR]

Hospitality makes possible things we don't expect, and one of its marvellous fruits is friendship. Here I bear witness to a spiritual movement that seeks to free us from the traps that imprison many people into retaining control, domination and privilege in times of horror. The power of the Ruah takes us into the very web of life that emerges filled with hope as a result of the courage of many people who have embraced their deepest dignity by embracing the dignity of all generations and of Mother Earth. [ABSTRACT FROM AUTHOR]

This article analyzes the involvement of mothers, fathers, and legal guardians in the active learning of children in primary and secondary schools in a particular scenario: online learning during the COVID-19 pandemic in Ecuador. For this purpose, a 45-question survey was applied to a sample of 6,206 people, segmented according to their geographic areas. In the rural area, the degree of involvement in virtual teaching-learning processes is reflected, in particular, in the establishment of sleep schedules and the acknowledgement by student of criticisms of their activities. For the urban area, children's anger management and the recognition of their strengths in subject matters are evident. In terms of strategies, in rural areas, parents put more pressure on students to carry out school activities, whereas in urban areas, parents talk more with their children when they lose control, paying more attention to their emotions and needs. Thus, the differentiation is summarized in the following expression: in rural areas, mothers, fathers, and guardians focus on discipline, while in urban areas they are oriented towards the academic and emotional spectrum. [ABSTRACT FROM AUTHOR]

This article presents an accurate analytical model (AM) for synchronous reluctance machine (SynRM) that incorporates the effect of stator slots on the air gap flux density and torque waveforms. From the formulation of magnetic potential in the air gap for both the stator and rotor, the flux density is obtained, considering the first harmonic of the flux density and the electric loading, the average torque is calculated using the Lorentz’s force. The ripple torque is obtained from the energy stored in magnetic circuit. The method is developed for a rotor with one flux barrier per pole and then extended to a larger number of barriers. To validate the results obtained by the AM proposed finite element analysis have been carried out. Several comparisons have been derived considering different rotor positions as well as different harmonic orders, and the pros and cons of the method are highlighted. The model performs fast and can predict results with high accuracy, and can be adopted to speed up the preliminary design and optimizations of this type of motors, with respect to finite element. In addition, from the analytical expressions it is possible to obtain all the correlations between electrical, magnetic, and geometrical characteristics of the machine, with the advantage of enabling a faster machine design. [ABSTRACT FROM AUTHOR]

This paper proposes a new method to estimate behavioural curves from Near-Infra-Red (NIR) iris images for classifying Fitness for Duty using a biometric capture device. Fitness for Duty (FFD) techniques detect whether a subject is Fit to safely perform a given task, which means no reduced alertness condition and security, or the subject is unfit, that could impact a reduced alertness condition by sleepiness or consumption of alcohol and drugs. The analysis showed essential differences in pupil and iris behaviour to classify the workers in "Fit" or "Unfit" conditions. The best results can distinguish subjects robustly under alcohol, drug consumption, and sleep conditions. The Multi-Layer-Perceptron and Gradient Boosted Machine reached the best results in all groups with an overall accuracy for Fit and Unfit classes of 74.0% and 75.5%, respectively. These results open a new application for iris capture devices. • This work is a step forward in Iris biometric applications. • This research proposes a new database and method to detect Fitness for Duty. • This paper proposes a new method to estimate behavioural curves from iris images • Fitness for Duty allows us to detect Fit/Unfit subjects and save lives • This method classifies alcohol, drug, and sleepiness using an iris image. [ABSTRACT FROM AUTHOR]

The LivDet‐2020 competition focuses on Presentation Attacks Detection (PAD) algorithms, has still open problems, mainly unknown attack scenarios. It is crucial to enhance PAD methods. This can be achieved by augmenting the number of Presentation Attack Instruments (PAI) and Bona fide (genuine) images used to train such algorithms. Unfortunately, the capture and creation of PAI and even the capture of Bona fide images are sometimes complex to achieve. The generation of synthetic images with Generative Adversarial Networks (GAN) algorithms may help and has shown significant improvements in recent years. This paper presents a benchmark of GAN methods to achieve a novel synthetic PAI from a small set of periocular near‐infrared images. The best PAI was obtained using StyleGAN2, and it was tested using the best PAD algorithm from the LivDet‐2020. The synthetic PAI was able to fool such an algorithm. As a result, all images were classified as Bona fide. A MobileNetV2 was trained using the synthetic PAI as a new class to achieve a more robust PAD. The resulting PAD was able to classify 96.7% of synthetic images as attacks. BPCER10 was 0.24%. Such results demonstrated the need for PAD algorithms to be constantly updated and trained with synthetic images. [ABSTRACT FROM AUTHOR]

A mathematical model for the kinetics, composition and molar mass development of the bulk reversible addition-fragmentation chain transfer (RAFT) copolymerization of glycidyl methacrylate (GMA) and styrene (St), at several GMA molar feed fractions at 103 °C, in the presence of 2-cyano isopropyl dodecyl trithiocarbonate as the RAFT agent and 1,1′-azobis(cyclohexane carbonitrile), as the initiator, is presented. The copolymerization proceeded in a controlled manner and dispersities of the copolymers remained narrow even at high conversions. Experimental data and calculated profiles of conversion versus time, composition versus conversion and molar mass development for the RAFT copolymerization of St and GMA agreed well for all conditions tested, including high-conversion regions. The kinetic rate constants associated with the RAFT- related reactions and diffusion-controlled parameters were properly estimated using a weighted nonlinear multivariable regression procedure. The mathematical model developed in this study may be used as an aid in the design and upscaling of industrial RAFT polymerization processes. [ABSTRACT FROM AUTHOR]

Background: The burden of musculoskeletal conditions continues to grow in low‐ and middle‐income countries. Among thousands of surgical outreach trips each year, few organizations electronically track patient data to inform real‐time care decisions and assess trip impact. We report the implementation of an electronic health record (EHR) system utilized at point of care during an orthopedic surgical outreach trip. Methods: In March 2023, we implemented an EHR on an orthopedic outreach trip to guide real‐time care decisions. We utilized an effectiveness‐implementation hybrid type 3 design to evaluate implementation success. Success was measured using outcomes adopted by the World Health Organization, including acceptability, appropriateness, feasibility, adoption, fidelity, and sustainability. Clinical outcome measures included adherence to essential quality measures and follow‐up numerical rating system (NRS) pain scores. Results: During the 5‐day outreach trip, 76 patients were evaluated, 25 of which underwent surgery beforehand. The EHR implementation was successful as defined by: mean questionnaire ratings of acceptability (4.26), appropriateness (4.12), feasibility (4.19), and adoption (4.33) at least 4.00, WHO behaviorally anchored rating scale ratings of fidelity (6.8) at least 5.00, and sustainability (80%) at least 60% follow‐up at 6 months. All clinical quality measures were reported in greater than 80% of cases with all measures reported in 92% of cases. NRS pain scores improved by an average of 2.4 points. Conclusions: We demonstrate successful implementation of an EHR for real‐time clinical use on a surgical outreach trip. Benefits of EHR utilization on surgical outreach trips may include improved documentation, minimization of medical errors, and ultimately improved quality of care. [ABSTRACT FROM AUTHOR]

Face Morphing Attacks pose a threat to the security of identity documents, especially with respect to a subsequent access control process, because they allow both involved individuals to use the same document. Several algorithms are currently being developed to detect Morphing Attacks, often requiring large data sets of morphed face images for training. In the present study, face embeddings are used for two different purposes: first, to pre-select images for the subsequent large-scale generation of Morphing Attacks, and second, to detect potential Morphing Attacks. Previous studies have demonstrated the power of embeddings in both use cases. However, we aim to build on these studies by adding the more powerful MagFace model to both use cases, and by performing comprehensive analyses of the role of embeddings in pre-selection and attack detection in terms of the vulnerability of face recognition systems and attack detection algorithms. In particular, we use recent developments to assess the attack potential, but also investigate the influence of morphing algorithms. For the first objective, an algorithm is developed that pairs individuals based on the similarity of their face embeddings. Different state-of-the-art face recognition systems are used to extract embeddings in order to pre-select the face images and different morphing algorithms are used to fuse the face images. The attack potential of the differently generated morphed face images will be quantified to compare the usability of the embeddings for automatically generating a large number of successful Morphing Attacks. For the second objective, we compare the performance of the embeddings of two state-of-the-art face recognition systems with respect to their ability to detect morphed face images. Our results demonstrate that ArcFace and MagFace provide valuable face embeddings for image pre-selection. Various open-source and commercial-off-the-shelf face recognition systems are vulnerable to the generated Morphing Attacks, and their vulnerability increases when image pre-selection is based on embeddings compared to random pairing. In particular, landmark-based closed-source morphing algorithms generate attacks that pose a high risk to any tested face recognition system. Remarkably, more accurate face recognition systems show a higher vulnerability to Morphing Attacks. Among the systems tested, commercial-off-the-shelf systems were the most vulnerable to Morphing Attacks. In addition, MagFace embeddings stand out as a robust alternative for detecting morphed face images compared to the previously used ArcFace embeddings. The results endorse the benefits of face embeddings for more effective image pre-selection for face morphing and for more accurate detection of morphed face images, as demonstrated by extensive analysis of various designed attacks. The MagFace model is a powerful alternative to the often-used ArcFace model in detecting attacks and can increase performance depending on the use case. It also highlights the usability of embeddings to generate large-scale morphed face databases for various purposes, such as training Morphing Attack Detection algorithms as a countermeasure against attacks. [ABSTRACT FROM AUTHOR]

The study of this article mainly focuses on the assessment and performance of current and voltage inverters in ozone generation, applying power density modulation (PDM) and typical operation. The topologies designed were a voltage-source full-bridge inverter (VSFBI), a current-source full-bridge inverter (CSFBI), and a CSFBI without considers the PDM. The inverters were analyzed and implemented considering an inductor–capacitor–capacitor (LCC) series–parallel resonant tank for the VSFBI and an LC parallel resonant tank for the CSFBI. The duty cycle impact (Dm) of the modulation signal was analyzed, and all inverters were compared. Based on the results, the decrease in Dm allows increasing the ozone generation because of avoiding the dissociation of the ozone molecules. The maximum concentration and efficacy presented by the VSFBI in ozone production were 620 gr/m3 and 0.155 gr/min. Also, the maximum electrical efficiency was 91%; it was presented by the CSFBI without PDM. [ABSTRACT FROM AUTHOR]

Background and Objectives: There is much interest in adding social variables to hospital performance assessments. Many of the existing analyses, however, already include patients' diagnosis data, and it is not clear that adding a social adjustment variable would improve the quality of the results: the growing literature on this issue provides mixed results. The purpose in this study was to add evidence from a developing country into this discussion. Methods: We estimate the efficiency of hospitals controlling for casemix, with and without adjusting the hospital's casemix for the patients' sociodemographic variables. The magnitude of the adjustment is based on the observed impact of age, sex, and income on length of stay, conditional on the diagnosis related group (DRG). We use a data envelopment analysis (DEA) to assess the efficiency of 50 Chilean hospitals' discharges, including 780 DRGs and covering about 60% of total discharges in Chile from 2013 to 2015. Results: We found that the sociodemographic adjustment introduces very small changes in the DEA estimation of efficiency. The underlying reason is the relatively low influence of sociodemographics on hospital costs, conditional on DRG, and the changing pattern of sociodemographics across DRGs for any given hospital. Conclusion: We conclude that the casemix-adjusted estimation of hospital efficiency is robust to the heterogeneity of patients' sociodemographic heterogeneity across hospitals. These results confirm, in a developing country, what has been observed in developed countries. For management purposes, then, the processing costs of adding social variables into hospitals' performance assessments might not be justified. [ABSTRACT FROM AUTHOR]

Historias de resistencia que atesoran el misterio de la dignidad humana son evocadas e invocadas como discernimiento inicial de los cambios que vienen aconteciendo, como señales de esperanza, en los contextos de la violencia global. Analizamos un cambio de temporalidad aunado a un cambio epistémico y antropológico, que constituyen una invitación a ser recibidos en lo hondo de las heridas que subyacen en el no-lugar de los ciclos de dominación, condenación y sacrificio, para recibir allí la fuerza mesiánica de la redención. [ABSTRACT FROM AUTHOR]

Starting from stories of resistance that store the mystery of human dignity, the article examines the changes taking place, as signs of hope, in the contexts of global violence. It analyses a change in the quality of time, combined with an epistemological and anthropological change, that constitutes and invitation to be received in the depths of the wounds existing in the nowhere of cycles of domination, condemnation and sacrifice in order to receive there the messianic force of redemption. [ABSTRACT FROM AUTHOR]

Most gender classifications methods from near‐infrared (NIR) images have used iris information. Recent work has explored the use of the whole periocular iris region which has surprisingly achieved better results. This suggests the most relevant information for gender classification is not located in the iris as expected. In this work, the authors analyse and demonstrate the location of the most relevant features that describe gender in periocular NIR images and evaluate their influence in classification. Experiments show that the periocular region contains more gender information than the iris region. They extracted several features (intensity, texture, and shape) and classified them according to their relevance using the XgBoost algorithm. Support vector machine and nine ensemble classifiers were used for testing gender accuracy when using the most relevant features. The best classification results were obtained when 4000 features located on the periocular region were used (89.22%). Additional experiments with the full periocular iris images versus the iris‐occluded images were performed. The gender classification rates obtained were 84.35 and 85.75%, respectively. From results, they suggest focusing only on the surrounding area of the iris. This allows us to realise a faster classification of gender from NIR periocular images. [ABSTRACT FROM AUTHOR]

This paper presents an igniter circuit for high-intensity-discharge (HID) lamps based on an inverter and a resonant tank that has been adapted to stabilize inductively an HID lamp by means of applying low-frequency quasi-square waveforms to voltage and current in the lamp in order to reduce the presence of the acoustic resonances. With the proposed improvement, the igniter circuit performs three different functions: 1) the lamp ignition; 2) the arc stabilization; and 3) the acoustic resonances reduction. This proposal allows the use of fewer components, and less energy processing is minimized, so the resulting ballast is cheaper and more efficient than other ballast that avoids the acoustic resonances when they are working with square waveforms in the lamp voltage and current. The circuit was validated experimentally by using a 70 W conventional high-pressure sodium lamp, which is operated with a frequency of 2 kHz. The results were an electrical efficiency of 94%, a crest factor in the lamp current of 1.41, and it was not observed the presence of acoustic resonances. [ABSTRACT FROM AUTHOR]

The use of reactive tri-block copolymers of styrene (S), glycidyl methacrylate (GMA), and butyl acrylate (BA) synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization as chain extenders of recycled poly (ethylene terephthalate) (R-PET) by melt processing is reported. Emphasis is placed on the influence of controlled copolymer structures and glycidyl methacrylate content on physical properties, thermal properties and rheological behavior of recycled PET. RAFT-synthesized reactive copolymers turned out to be very effective chain extenders leading to an increase in the molar mass intrinsic viscosity and diminished melt flow, indicating better melt elasticity and processability of R-PET. Tensile and impact analysis showed that functional GMA blocks reacted with PET end groups, causing a dramatic increase in the elongation-at-break and significant improvement of impact and tensile strength. Complex viscosity and rheological moduli of R-PET also increase greatly, indicating that flexibility of modified R-PET is improved. The van Gurp–Palmen plot of chain-extended R-PET confirms the increase in melt elasticity. Image 10 • Reactive copolymers synthesized by RAFT polymerization permit an efficient chain extension process for rPET. • The melt flow index and intrinsic viscosity increase to values close to those of virgin PET. • The addition of reactive block copolymers increases the complex viscosity and moduli of the modified rPET. • The polymer modifications increase the elastic properties and the viscosity of rPET by the addition of a chain extender. [ABSTRACT FROM AUTHOR]

Abstract The use of multi-block copolymers of styrene (S), maleic anhydride (MA), and butyl acrylate (BA) (poly((S-alt-MA)-block-S-block-BA-block-S-block-(S-alt-MA))) synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization as asphalt modifiers, is reported. Emphasis is placed on the influence of controlled copolymer structures and maleic anhydride content on physical properties, morphology, thermal stability and rheological behavior of asphalt blends. Our results show that the degree of asphalt modification is a function of both, copolymer structure and maleic anhydride content. Rheological, thermal and microstructure analyses reveal that the addition of reactive copolymers increases chemical interactions with asphalt polar fractions. Significant improvement of viscosity, elasticity, and storage stability are observed in the blends with SMA-S-BA-S-SMA copolymers at MA concentrations of 2–6% compared to copolymers without functional groups. Graphical abstract Image 1083238 Highlights • Copolymers with controlled functionalities were synthesized by RAFT polymerization. • Reactive multi-block copolymers turned out to be effective asphalt modifiers. • Functional SMA blocks react with asphalt reactive groups to render stable dispersions. • Reactive copolymers improved compatibility and rheological performance of asphalt. [ABSTRACT FROM AUTHOR]

Summary: In this paper, the analysis, design, and implementation of a power supply based on a multi‐stage‐shunt class E amplifier applied to ozone generation are presented. The proposed topology operates with pulsating waveforms and allows unidirectional energy flow from the power supply to the load with no energy return. Furthermore, due to the multi‐stage operation, it presents a lower stress in the switches compared with other similar topologies. To validate the proposed topology, a prototype was designed to feed a set of ozone generating cells in a power range of 0 to 500 W. This prototype provides an efficiency of 95% with an ozone production of 10.5 g/h and efficacy of 22.89 g/kWh. The proposed power supply is an alternative to feed any other type of dielectric barrier discharge load while keeping the efficiency of the power supply above 90%. The analysis, design, and implementation of a power supply based on a multi‐stage‐shunt class E amplifier applied to ozone generation are presented; due to the multi‐stage operation, it presents a lower stress in the switches compared with other similar topologies and higher efficiency. To validate the proposed topology, a prototype was designed to feed a set of ozone generating cells in a power range of 0 to 500 W. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The RAFT polymerization of styrene and maleic anhydride monitored by DSC is addressed. • Temperature and monomeric composition modifies the polymerization rate and molar mass. • At low conversions, activation and deactivation are chemically controlled. • At high conversion the activation energy decrease due to diffusion controlled effects. • Diffusion effects on the macro-radicals leads to increased polymerization rates. Abstract A kinetic study of the copolymerization of styrene (S) and maleic anhydride (MA) in the presence of dibenzyl trithiocarbonate (DBTTC) as RAFT agent monitored by differential scanning calorimetry, is presented. The results obtained indicate that the polymerization proceeded in a controlled manner. The average activation energy (E) of the copolymerization obtained by Ozawa and Kissinger methods (62 ± 2 kJ mol−1) showed good agreement with the E value obtained by the isothermal method (67 ± 2 kJ mol−1). These values agree well with the value of 65 kJ mol−1 reported for the nitroxide-mediated copolymerization of S and MA. Calculations using isoconversional methods show that Ea is not constant within the whole conversion range. As the reaction proceeds and higher conversions are reached, Ea decreases to lower values due to diffusion-controlled effects. A first-order reaction model is applied to determine overall kinetic rate constants at different temperatures and different MA molar feed fractions. Polymerization rate increased approximately four orders of magnitude when temperature changed from 90 °C to 110 °C. Polymerization rate is also strongly affected by MA content. It increased by a factor of about three when MA changed from 30% to 50% molar content in the copolymer. [ABSTRACT FROM AUTHOR]

Soft consensus is a relevant topic in group decision making problems. Soft consensus measures are utilized to reflect the different agreement degrees between the experts leading the consensus reaching process. This may determine the final decision and the time needed to reach it. The concept of coincidence has led to two main approaches to calculating the soft consensus measures, namely, concordance among expert preferences and concordance among individual solutions. In the first approach the coincidence is obtained by evaluating the similarity among the expert preferences, while in the second one the concordance is derived from the measurement of the similarity among the solutions proposed by these experts. This paper performs a comparative study of consensus approaches based on both coincidence approaches. We obtain significant differences between both approaches by comparing several distance functions for measuring expert preferences and a consensus measure over the set of alternatives for measuring the solutions provided by experts. To do so, we use the nonparametric Wilcoxon signed-ranks test. Finally, these outcomes are analyzed using Friedman mean ranks in order to obtain a quantitative classification of the considered measurements according to the convergence criterion considered in the consensus reaching process. [ABSTRACT FROM AUTHOR]

In many parts of the nervous system, signals pass across multiple synaptic relays on their way to a destination, but little is known about how these relays form and the function they serve. To get some insight into this question we ask how the connectivity patterns are organized at two successive synaptic relays in a simple, cholinergic efferent pathway. We found that the organization at successive relays in the parasympathetic nervous system strongly resemble each other despite the different embryological origin and physiological properties of the pre- and postsynaptic cells. Additionally, we found a similar developmental synaptic pruning and elaboration strategy is used at both sites to generate their adult organizations. The striking parallels in adult innervation and developmental mechanisms at the relays argue that a general strategy is in operation. We discuss why from a functional standpoint this structural organization may amplify central signals while at the same time maintaining positional targeting. [ABSTRACT FROM AUTHOR]

This paper presents a methodology to produce hybrid multifunctional materials based on graphene coated-metal nanoparticles supported on carbon nanotubes (M-CNT). These hybrid materials were synthetized by impregnation-reduction-decoration (IRD) methodology. Supported metal nitrates, were decomposed and reduced in-situ with CNT. After the reducing procedure, metal particles were treated with methane pulses at temperatures between 700 °C and 900 °C to encapsulate them into a few graphene sheets. These hybrid materials were characterized through different analytical techniques. In-situ X-ray diffraction analysis showed that the decomposition of nitrates occurs simultaneously with an in-situ reduction of metal particles by utilizing CNT as reducing agent. The nucleation of these metal particles preferentially starts over carbon nanotubes defects. Synthetized metal nanoparticles are active for methane decomposition, allowing the deposition of carbonaceous materials and their crystallization as graphene layers covering the metal particles (between one and four graphene layers). Magnetic characterization suggests that these hybrid materials can be used for development of magnetic storage devices, while their multifunctional properties could be potentially exploited for development of a variety of catalysts and sensors. [ABSTRACT FROM AUTHOR]

Year 2013 revealed that nearly a thousand students who had obtained the highest general average at their respective high schools could not apply to universities via the Chilean university admission process -Sistema Único de Admisión (SUA)-, because they did not reach the minimum score requirement at the standardized university selection test called Prueba de Selección Universitaria (PSU). Universidad de Santiago then initiated a pilot project to a) make a timely contact with at least some of these students; b) exempt them from their PSU score requirement; c) invite them to access the Science and Humanities College Program; and d) accompany them until they became academically indistinguishable from their peers. During 2015, 10 students entered Universidad de Santiago in this process and in 2016; there were 26 new students in the university. This paper presents the latter early results in terms of average grades and retention, compared to those of students who entered via PSU. [ABSTRACT FROM AUTHOR]

This paper is aimed to report the consequences in the use of the well-known bootstrap technique in single-phase current-fed full-bridge resonant inverters (SPCFFBRIs) operating with and without reactive energy. Based on both simulations (using the PSPICE software) and experiments it is shown that this technique is not feasible for this type of inverters when the load is predominantly reactive. The bootstrap technique conveniently operates when the load is purely resistive or resonant. The unfeasibility in the use of the bootstrap technique with reactive or nonresonant loads comes from the fact that the load voltage is applied to the bootstrap capacitor and, consequently, to the gate of the floating MOSFET, producing an imminent damage both in the control circuit and in the floating MOSFET. Therefore, other alternatives for feeding the floated MOSFETs must be considered. [ABSTRACT FROM AUTHOR]

We propose a numerical surface integral method to study complex acoustic systems, for interior and exterior problems. The method is based on a parametric representation in terms of the arc's lengths in curvilinear orthogonal coordinates. With this method, any geometry that involves quadric or higher order surfaces, irregular objects or even randomly rough surfaces can be considered. In order to validate the method, the modes in cubic, spherical and cylindrical cavities are calculated and compared to analytical results, which produced very good agreement. In addition, as examples, we calculated the scattering in the far field and the near field by an acoustic sphere and a cylindrical structure with a rough cross-section. [ABSTRACT FROM AUTHOR]

The early detection of drowsiness has become vital to ensure the correct and safe development of several industries' tasks. Due to the transient mental state of a human subject between alertness and drowsiness, automated drowsiness detection is a complex problem to tackle. The electroencephalography signals allow us to record variations in an individual's brain's electrical potential, where each of them gives specific information about a subject's mental state. However, due to this type of signal's nature, its acquisition, in general, is complex, so it is hard to have a large volume of data to apply techniques of Deep Learning for processing and classification optimally. Nevertheless, Capsule Neural Networks are a brand-new Deep Learning algorithm proposed for work with reduced amounts of data. It is a robust algorithm to handle the data's hierarchical relationships, which is an essential characteristic for work with biomedical signals. Therefore, this paper presents a Deep Learning-based method for drowsiness detection with CapsNet by using a concatenation of spectrogram images of the electroencephalography signals channels. The proposed CapsNet model is compared with a Convolutional Neural Network, which is outperformed by the proposed model, which obtains an average accuracy of 86,44 % and 87,57% of sensitivity against an average accuracy of 75,86% and 79,47% sensitivity for the CNN, showing that CapsNet is more suitable for this kind of datasets and tasks. • A Capsule Network for drowsiness detection method is proposed. • The system is based on spectrogram images concatenate information from Fz and Pz. • The traditional drowsiness detection methods need a big number of data. • The proposed method improves the results even with a small number of images. • The proposed method outperforms state of the art in comparison with CNN and ML. [ABSTRACT FROM AUTHOR]

This paper deals with the contribution of expanded polystyrene (EPS) particles on fire resistance, thermal conductivity and compressive strength of foamed concrete. The foamed (FC) and polystyrene foamed (PFC) concrete were designed for densities ranging from 1200 kg/m 3 to 150 kg/m 3 with an EPS volume range of 0–82.22% and water-cement ratio of 0.33. The foamed concrete (FC) with a density of 800 kg/m 3 and an EPS volume of 0% was designed as reference for polystyrene foamed concrete. The results indicated that increasing the volume of EPS causes a significant reduction of thermal conductivity, fire endurance and compressive strength of concrete. [ABSTRACT FROM AUTHOR]

In this work, we propose a two-dimensional photonic crystal-photonic crystal heterostructure that possesses the requirements for exciting an electromagnetic interface mode and investigate its interaction with photonic crystal waveguide modes. To study the interaction and coupling of both types of modes, the proper conditions to excite them are analyzed. Photonic crystal guided modes can appear in nearly any band gap when the photonic crystal has a line of defects within its lattice. Photonic crystal-photonic crystal surface modes can be excited at the junction of two different photonic crystals that share translation symmetry along the interface direction and have overlapped frequency band gaps. When this condition is met, dispersion relations of photonic crystal-photonic crystal surface modes will lie in the common region of both band gaps. Once the proper conditions are provided to excite these two modes, an interaction between them is possible. In the resulting calculations, a symmetric supercell and a plane wave basis are defined to numerically solve the wave equation. [ABSTRACT FROM AUTHOR]

In this study, bioleaching was carried out for the recovery of metals (copper, zinc, tin, lead, gold and silver) from printed circuit boards residues (PCBs), one of the most important wastes from electrical and electronic equipment, using an acidophilic iron-oxidizing bacterial consortium enriched with minerals from a gold mine in the Arequipa region, Peru. High-throughput sequencing and analysis of the 16S rRNA biomarker revealed that this consortium was predominantly composed of Tissierella, Acidiphilium and Leptospirillum bacteria, from which the latter is known to grow by chemolithotrophy through iron oxidation. After the enrichment process, the acidophilic iron-oxidizing consortium was first tested for its tolerance to different PCBs concentrations, showing best growth up to 10 g/L of PCBs and a tolerance index of 0.383. Based on these results, the bioleaching efficiency of the consortium was investigated for 10 g/L of PCBs in stirred tank reactors coupled to an aeration system, for 18 days. High bioleaching efficiencies were achieved for copper and zinc (69% and 91%, respectively), indicating that these two metals can be easily extracted in this leaching system. Lower extraction efficiencies were achieved for tin (16%) and gold (28%), while for lead and silver only a residual recovery (<0.25%) was detected. These results indicate that the enriched bacterial consortium originating from the Arequipa region, Peru, has a high capacity to recover different metals of economic importance. [ABSTRACT FROM AUTHOR]

Thalamus is a potent driver of cortical activity even though cortical synapses onto excitatory layer 4 neurons outnumber thalamic synapses 10 to 1. Previous in vitro studies have proposed that thalamocortical (TC) synapses are stronger than corticocortical (CC) synapses. Here, we investigated possible anatomical and physiological differences between these inputs in the rat in vivo. We developed a high-throughput light microscopy method, validated by electron microscopy, to completely map the locations of synapses across an entire dendritic tree. This demonstrated that TC synapses are slightly more proximal to the soma than CC synapses, but detailed compartmental modeling predicted that dendritic filtering does not appreciably favor one synaptic class over another. Measurements of synaptic strength in intact animals confirmed that both TC and CC synapses are weak and approximately equivalent. We conclude that thalamic effectiveness does not rely on enhanced TC strength, but rather on coincident activation of converging inputs. [ABSTRACT FROM AUTHOR]

In this work, the parallel implementation of a segmentation algorithm based on the gradient vector flow (GVF) deformable model in a graphics processing unit (GPU) is presented. The proposed implementation focuses on the parallelization of the computation of the GVF field. In order to make a performance comparison of the proposed GPU algorithm, an OpenMP-based implementation is presented too. We also present an analysis of the textures and global memory performance in the computing of the GVF field. To improve the efficiency and the performance of the active contour segmentation, a novel snaxel reallocation method is proposed. The main advantage of the reallocation process is the small linear system needed to perform the segmentation and its low computational load. To assure the convergence of the active contour deformation, we propose a stopping criterion based on the root mean square error for the iterative solution of the evolution equations. [ABSTRACT FROM AUTHOR]

In this article, we propose a mathematical model using the port-Hamiltonian formalism for a satellite's three-axis attitude system comprising fluid rings. Fluid rings are an alternative to reaction wheels used for the same purpose, since, for the same mass, they can exert a greater torque than a reaction wheel as the fluid can circulate the periphery of the satellite. The port-Hamiltonian representation lays the foundation for a posterior controller that is feasible, stable, and robust based on the interconnection of the system to energy shaping and/or damping injection components, and by adding energy routing controllers. The torques exerted by the fluid rings are modeled using linear regression analysis on the experimental data got from a prototype of a fluid ring. Since the dynamics of turbulent flows is complex, the torques obtained by the prototype lead to a simpler first approach, leaving its uncertainties to a controller. Thus, the attitude system model could be tested in a future prototype before considering a spatial environment. [ABSTRACT FROM AUTHOR]

High power machine has become a large market for wind power and ship propulsion electric, among other applications. Since the size of these machines is much larger than conventional industrial ones, optimum design must be considered in order to reduce the material cost and increase profitability. In this paper, a simple analytic optimization algorithm is used to maximize the apparent airgap power transferred under tangential stress constraint. In this approach, close related expressions between the main design variables, operational restrictions, and external dimensions are derived to build the mathematical structure of the optimization process. To improve the torque capacity estimation of the designed machine, a correction procedure, based on the previous result, is used to remove the idealizations considered for the initial design. Close agreement with the finite element analysis results are found with this approach, which is based on analytical method. [ABSTRACT FROM AUTHOR]

A mathematical model for the anionic polymerization of isoprene using n-butyl lithium (n-BuLi) as initiator and N,N,N′,N′-tetramethylethylenediamine (TMEDA) as microstructure modifier, considering a system similar to a tetrapolymerization and a scheme of reaction that considers that the active sites are different in configuration, has been developed. Experimental data of conversion versus time and structure development (1,4-cis, 1,4-trans, vinyl or isopropenyl units) were taken from the literature. Since 1,4-cis structural units are difficult to measure, directly, we used reports based on indirect measurements for natural polyisoprene. The cis structural unit fraction was varied from 0.1 to 0.9 (referred to cis+trans content) in order to provide enough data for parameter estimation purposes. Rate expressions for monomer consumption as well as microstructure and dyad development were obtained from the proposed scheme of reaction. The fraction of active sites and dyad distribution were calculated using Markov chains theory, based on conditional probabilities. The kinetic model correctly describes the performance anionic polymerizations with and without TMEDA. [ABSTRACT FROM AUTHOR]

Summary: Using light and serial electron microscopy, we show profound refinements in motor axonal branching and synaptic connectivity before and after birth. Embryonic axons become maximally connected just before birth when they innervate ∼10-fold more muscle fibers than in maturity. In some developing muscles, axons innervate almost every muscle fiber. At birth, each neuromuscular junction is coinnervated by approximately ten highly intermingled axons (versus one in adults). Extensive die off of terminal branches occurs during the first several postnatal days, leading to much sparser arbors that still span the same territory. Despite the extensive pruning, total axoplasm per neuron increases as axons elongate, thicken, and add more synaptic release sites on their remaining targets. Motor axons therefore initially establish weak connections with nearly all available postsynaptic targets but, beginning at birth, massively redistribute synaptic resources, concentrating many more synaptic sites on many fewer muscle fibers. Analogous changes in connectivity may occur in the CNS. Video Abstract: Display Omitted [ABSTRACT FROM AUTHOR]

Normal aging and neurodegenerative diseases both lead to structural and functional alterations in synapses. Comparison of synapses that are generally similar but respond differently to insults could provide the basis for discovering mechanisms that underlie susceptibility or resistance to damage. Here, we analyzed skeletal neuromuscular junctions (NMJs) in 16 mouse muscles to seek such differences. We find that muscles respond in one of three ways to aging. In some, including most limb and trunk muscles, age-related alterations to NMJs are progressive and extensive during the second postnatal year. NMJs in other muscles, such as extraocular muscles, are strikingly resistant to change. A third set of muscles, including several muscles of facial expression and the external anal sphinter, succumb to aging but not until the third postnatal year. We asked whether susceptible and resistant muscles differed in rostrocaudal or proximodistal position, source of innervation, motor unit size, or fiber type composition. Of these factors, muscle innervation by brainstem motor neurons correlated best with resistance to age-related decline. Finally, we compared synaptic alterations in normally aging muscles to those in a mouse model of amyotrophic lateral sclerosis (ALS). Patterns of resistance and susceptibility were strikingly correlated in the two conditions. Moreover, damage to NMJs in aged muscles correlated with altered expression and distribution of CRMP4a and TDP-43, which are both altered in motor neurons affected by ALS. Together, these results reveal novel structural, regional and molecular parallels between aging and ALS. [ABSTRACT FROM AUTHOR]

In this article we report a new method for gender classification from frontal face images using feature selection based on mutual information and fusion of features extracted from intensity, shape, texture, and from three different spatial scales. We compare the results of three different mutual information measures: minimum redundancy and maximal relevance (mRMR), normalized mutual information feature selection (NMIFS), and conditional mutual information feature selection (CMIFS). We also show that by fusing features extracted from six different methods we significantly improve the gender classification results relative to those previously published, yielding 99.13% of the gender classification rate on the FERET database. [ABSTRACT FROM AUTHOR]

At birth, synaptic sites in developing rodent muscles are innervated by numerous motor axons. During subsequent weeks, this multiple innervation disappears as one terminal strengthens, and all the others are eliminated. Experimental perturbations that alter neuromuscular activity affect the rate of synaptic refinement, with more activity accelerating the time to single innervation and neuromuscular blockade retarding it. However, it remains unclear whether patterns of muscle use (driven by endogenous neuronal activity) contribute to the rate of synapse elimination. For this reason we examined the timing of supernumerary nerve terminal elimination at synapses in extraocular muscles (EOMs), a specialized set of muscles controlling eye movements. On the basis of their exceptionally high patterns of activity, we hypothesized that synaptic refinement would be greatly accelerated at these synapses. We found, however, that rates of synaptic refinement were only modestly accelerated in rectus and oblique EOMs compared with synapses in somite-derived skeletal muscle. In contrast to these results, we observed a dramatic delay in the elimination of supernumerary nerve terminals from synapses in the levator palpebrae superioris (LPS) muscle, a specialized EOM that initiates and maintains eyelid elevation. In mice, natural eye opening occurs at the end of the second postnatal week of development. Thus, although synapse elimination is occurring in most EOMs and somite-derived skeletal muscles, it appears to be dramatically delayed in a set of specialized eyelid muscles that remain immobile during early postnatal development. J. Comp. Neurol. 519:2907-2921, 2011. © 2011 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The anionic solution copolymerization of butadiene and styrene prepared by anionic living polymerization using an initiator composed of n-butyl lithium, and N,N,N′,N′-tetramethylethylenediamine as active center modifier was modeled as a tetrapolymerization. The kinetic model proposed considering that the reactivity of the active sites is different because of varying configurations cis, trans, vinyl, and styryl. From the reaction scheme expressions to rate of monomers consumption, microstructure and dyad formation were obtained. With the first-order Markov model, the expressions for the fraction of active sites and dyad distribution as a function of the conditional probabilities were obtained. Therefore, the model proposed is different to kinetic models previously reported, because it allows obtaining the parameters kinetic in order to know the distribution of the isomeric species presents in the copolymerization of butadiene and styrene, and the intrinsic reactivity of configurational active sites. The rate constants were determined by fitting to the conversion and dyad experimental data using the nonlinear least square method. The experimental data reported in the literature, monomer conversion and microstructure, in addition to dyad sequence distribution were correctly predicted. [ABSTRACT FROM AUTHOR]

The cellular basis of age-related behavioral decline remains obscure but alterations in synapses are likely candidates. Accordingly, the beneficial effects on neural function of caloric restriction and exercise, which are among the most effective anti-aging treatments known, might also be mediated by synapses. As a starting point in testing these ideas, we studied the skeletal neuromuscular junction (NMJ), a large, accessible peripheral synapse. Comparison of NMJ5 in young adult and aged mice revealed a variety of age-related structural alterations, including axonal swellings, sprouting, syn- aptic detachment, partial or complete withdrawal of axons from some postsynaptic sites, and fragmentation of the postsynaptic specialization. Alterations were significant by 18 mo of age and severe by 24 mo. A life-long calorie-restricted diet significantly decreased the incidence of pre- and postsynaptic abnormalities in 24-mo-old mice and attenuated age-related loss of motor neurons and turnover of muscle fibers. One month of exercise (wheel running) in 22-mo-old mice also reduced age-related synaptic changes but had no effect on motor neuron number or muscle fiber turnover. Time-lapse imaging in vivo revealed that exercise partially reversed synaptic alterations that had already occurred. These results demonstrate a critical effect of aging on synaptic structure and provide evidence that interventions capable of extending health span and lifespan can partially reverse these age-related synaptic changes. [ABSTRACT FROM AUTHOR]

In this paper, a negative-saliency permanent-magnet (PM) synchronous machine analysis is presented. This particular saliency feature is achieved by replacing a portion of the magnet material by a soft iron piece over the rotor pole. In this manner, the d-axis inductance is increased, whereas the q-axis inductance is almost not affected, leading to the condition that Ld is higher than Lq (negative saliency) corresponding to the inverse condition of typical PM machines. An expression for the optimum pole configuration is derived. It is shown that, with appropriate control of the stator current based on the machine's saliency, the unfavorable effects of magnet reduction on torque production can be compensated. It is also shown that the machine saliency affects the location of the operating points when it operates under vector control. Finally, the theoretical analysis is validated with experimental results obtained from a prototype axial-flux PM machine that exhibits negative saliency. [ABSTRACT FROM AUTHOR]

Abstract: The specific contact resistivity (ρ C) for aluminum (Al), silver (Ag) and indium (In) metallic contacts on CuInS2 thin films was determined from I–V measurements, with the purpose of having the most appropriate ohmic contact for TCO/CdS/CuInS2 solar cells; ρ C was measured using the transmission line method (TLM) for the metallic contacts evaporated on CuInS2 thin films deposited by spray pyrolysis with ratios x=[Cu]/[In]=1.0, 1.1, 1.3 and 1.5 in the spray solution. The results show that In contacts have the lowest ρ C values for CuInS2 samples grown with x=1.5. The minimum ρ C was 0.26Ωcm2 for the In contacts. This value, although not very low, will allow the fabrication of CuInS2 solar cells with a small series resistance. [Copyright &y& Elsevier]

Abstract: A diffuse interface type model, using an energy-based variational formulation with a free energy that is a function of the density and its gradients is presented. All of the boundary terms are retained and related to external surface forces, which can be of particular interest when considering the fluid–fluid–solid region. The numerical solution of these types of problems can be troublesome if a thin transition layer is desired. Here, Chebyshev pseudospectral methods with mesh adaptation for the solution of diffuse interface type problems are studied. A mesh adaptation algorithm based in the equidistribution principle following a continuation process is derived. In order to achieve high precision for problems exhibiting thin transition layers, a modified version of the arc-length monitor function is proposed which yields a sufficiently smooth coordinate transformation. At every step of the continuation process, a fixed number of iterations is implemented, so that the equidistribution equations are not solved completely at each step, which saves a considerable amount of computational effort. Numerical results for the static phase field model exhibiting thin transition layers are presented. [Copyright &y& Elsevier]

Reconstruction of the complete set of motor axons innervating a muscle reveals wiring variability, even among corresponding neurons on the left and right sides of the same animal. [ABSTRACT FROM AUTHOR]

This paper addresses the evaluation of the heat transfer capability of a finned frame for different velocities of the cooling fan and different numbers and dimensions of the fins. As the heat transfer is highly dependent on the air speed and turbulence, separate evaluations are done in four axial sectors of four different frames. For each frame, each sector is thermally isolated and evenly heated by an internal cylindrical heater with controlled losses. The experimental results allow computing the local transfer coefficient on each axial sector in terms of the fin dimensions and cooling air velocity, and using these empirical coefficients, it is possible to evaluate the thermal capability of the frames and/or to compute the temperature gradient needed to dissipate certain losses. Based on these results, a simple and accurate method to size finned frames is proposed. [ABSTRACT FROM AUTHOR]

We designed and tested a new axial flux permanent-magnet machine (AFPM) with field weakening capability. This paper provides a summary of key design features, optimization, and test results of an AFPM prototype. The proposed field weakening method is based on the control of the d-axis component of the armature reaction flux. The paper focuses on the air-gap flux control capability of the topology. [ABSTRACT FROM AUTHOR]

The aim of this contribution is to assess the use poly(styrene-co-glycidyl methacrylate-b-styrene) copolymers synthesized by nitroxide mediated polymerization (NMP) as chain extenders in the recycling of poly(lactic acid) biopolyester. Concisely, the addition of such block copolymers during the melt processing of recycled poly(lactic acid) (rPLA) leads to important increases in the viscosity average molecular weight of modified polymeric materials. Molar masses increase from 31,000 g/mol for rPLA to 48,000 g mol−1 for the resulting rPLA/copolymer blends (bPLA). Fortuitously, this last value is nearly the same as the one for pristine PLA, which constitutes a first piece of evidence of the molar mass increase of the recycled biopolymer. Thermograms of chain extended rPLA show significant decreases in cold crystallization temperature and higher crystallinity degrees due to the chain extension process using NMP-synthesized copolymers. It was found that increasing epoxide content in the NMP-synthesized copolymers leads to increased degrees of crystallinity and lower cold crystallization temperatures. The rheological appraisal has shown that the addition of NMP synthesized copolymers markedly increases complex viscosity and elastic modulus of rPLA. Our results indicate that P(S-co-GMA)-b-S) copolymers act as efficient chain extenders of rPLA, likely due to the reaction between the epoxy groups present in P(S-co-GMA)-b-PS and the carboxyl acid groups present in rPLA. This reaction positively affects viscometric molar mass of PLA and its performance. [ABSTRACT FROM AUTHOR]