99 research outputs found

    Anomaly Detection in Activities of Daily Living with Linear Drift

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    Anomalyq detection in Activities of Daily Living (ADL) plays an important role in e-health applications. An abrupt change in the ADL performed by a subject might indicate that she/he needs some help. Another important issue related with e-health applications is the case where the change in ADL undergoes a linear drift, which occurs in cognitive decline, Alzheimer’s disease or dementia. This work presents a novel method for detecting a linear drift in ADL modelled as circular normal distributions. The method is based on techniques commonly used in Statistical Process Control and, through the selection of a convenient threshold, is able to detect and estimate the change point in time when a linear drift started. Public datasets have been used to assess whether ADL can be modelled by a mixture of circular normal distributions. Exhaustive experimentation was performed on simulated data to assess the validity of the change detection algorithm, the results showing that the difference between the real change point and the estimated change point was 4.90−1.98+3.17 days on average. ADL can be modelled using a mixture of circular normal distributions. A new method to detect anomalies following a linear drift is presented. Exhaustive experiments showed that this method is able to estimate the change point in time for processes following a linear drift

    A Generative Method for Indoor Localization Using Wi-Fi Fingerprinting

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    Indoor localization is an enabling technology for pervasive and mobile computing applications. Although different technologies have been proposed for indoor localization, Wi-Fi fingerprinting is one of the most used techniques due to the pervasiveness of Wi-Fi technology. Most Wi-Fi fingerprinting localization methods presented in the literature are discriminative methods. We present a generative method for indoor localization based on Wi-Fi fingerprinting. The Received Signal Strength Indicator received from a Wireless Access Point is modeled by a hidden Markov model. Unlike other algorithms, the use of a hidden Markov model allows ours to take advantage of the temporal autocorrelation present in the Wi-Fi signal. The algorithm estimates the user’s location based on the hidden Markov model, which models the signal and the forward algorithm to determine the likelihood of a given time series of Received Signal Strength Indicators. The proposed method was compared with four other well-known Machine Learning algorithms through extensive experimentation with data collected in real scenarios. The proposed method obtained competitive results in most scenarios tested and was the best method in 17 of 60 experiments performed

    Medidas de controlo vetorial de mosquitos em caso de surtos de arboviroses

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    This paper proposes developing monitoring and control strategies with regard to various species of mosquitoes well- established in the Iberian Peninsula based on their ecological characteristics for two different scenarios of arbovirus outbreaks: One for controlling Aedes albopictus as a vector transmitting dengue, zika and chikungunya in urban environments and the other for keeping in check the Culicinae species linked to the transmission of the West Nile virus in rural and peri-urban environments. These entomological monitoring and control plans are based on experiments conducted in different Spanish provinces over the past few years. The results of the control treatments carried out and the relevance of the coordination and cooperation among public and private entities are discussed herein in detail.En el presente artículo se plantea el desarrollo de estrategias de vigilancia y control de diversas especies de mosquitos asentados en la Península Ibérica, basados en sus características ecológicas, para dos escenarios diferenciados de brotes de arbovirosis: fundamentalmente para el control de Aedes albopictus como vector transmisor en entornos urbanos (dengue, zika y chikungunya) y, en segundo lugar, el control de especies de culicinos ligados al medio rural y periurbano (virus West Nile). Estos planes de vigilancia y control entomológico se basan en experiencias llevadas a cabo en diferentes provincias españolas a lo largo de los últimos años. El resultado de los tratamientos de control realizados y la relevancia de la coordinación y cooperación entre entidades públicas y privadas, se discuten con detalle en el presente artículo.Este artigo propõe o desenvolvimento de estratégias de vigilância e controlo de várias espécies de mosquitos instaladas na Península Ibérica, com base nas suas características ecológicas, para dois cenários distintos de surto de arboviroses: fundamentalmente para o controle de Aedes albopictus como vetor transmissor em ambientes urbanos (dengue, zika e chikungunya) e, em segundo lugar, o controlo de espécies de culicídeos ligados aos meios rurais e periurbanos (vírus do Nilo Ocidental). Estes planos de vigilância e controle entomológico baseiam-se em experiências realizadas em diferentes províncias espanholas nos últimos anos. O resultado dos tratamentos de controlo efetuados e a relevância da coordenação e cooperação entre entidades públicas e privadas são discutidos em pormenor neste artigo

    Carbon footprint: the case of four chicken meat products sold on the Spanish market

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    Despite its relatively low environmental impact within the livestock sector, the poultry sector still faces its own environmental challenges that need to be addressed. The present paper uses life cycle assessment to quantify greenhouse gas emissions, from cradle to slaughterhouse gate, of four chicken meat products: whole carcass, wings, breast fillets, and leg quarters. The main contribution of the present study is that it provides a detailed analysis of different chicken meat cuts, testing mass and economic allocation choices and showing that economic allocation better reflects the causality of the cutting process. We recommend that a distinction should be made between whole carcass and meat cuts, as there are significant differences in meat content and climate change results between these two categories. This is not so clear in the literature, nor in the LEAP guideline for the poultry sector. The study was performed by using disaggregated inventory data from Spain, for the first time. Results show that the major contributors to environmental impact are feed production (>70%), electricity use (10.2%), and fossil fuel combustion (8.1%). Packaging did not significantly contribute to the climate change impact of the chicken products evaluated (0.4-3.4% contribution, depending on the type of packaging and product considered).The authors wish to acknowledge the financial support from the Spanish Ministry of Science and Innovation to the project KAIROS-BIOCIR (PID2019-104925RB-C32). The first author also appreciates the support (2021FI_B 00100) from the Secretariat for Universities and Research of the Ministry of Business and Knowledge of the Government of Catalonia and the European Social Fund. Finally, the authors are grateful to Grupo SADA p.a., S.A for their support in this study

    Can we speak of a negative psychological tetrad in sports? A probabilistic Bayesian study on competitive sailing

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    INTRODUCTION: Researchers display an interest in studying aspects like the mental health of high-performance athletes; the dark side of sport, or the earliest attempts to study the so-called dark triad of personality in both initiation and high-performance athletes. Therefore, the objective of this paper is to determine the possible existence and magnitude of negative psychological aspects within a population of competition sailors and from a probabilistic point of view, using Bayesian Network analysis. METHODS: The study was carried out on 235 semi-professional sailors of the 49er Class, aged between 16 and 52 years (M = 24.66; SD = 8.03). RESULTS: The results show the existence of a Negative Tetrad-formed by achievement burnout, anxiety due to concentration disruption, amotivation and importance given to error-as a probabilistic product of the psychological variables studied: motivation, anxiety, burnout and fear of error. CONCLUSION: These results, supported by Bayesian networks, show holistically the influence of the social context on the psychological and emotional well-being of the athlete during competition at sea

    Environmental and yield comparison of quick extraction methods for caffeine and chlorogenic acid from spent coffee grounds

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    This study aims to provide an overview of different extraction methods to obtain chlorogenic acid (CA) and caffeine (Caf) from spent coffee grounds (SCG). This overview shows that the quantity extracted is highly dependent on the type of SCG, so experiments using the same SCG are needed to compare different methods. Three easy and simple extraction methods will be tested at a laboratory scale and environmentally compared. All three experiments were of 1 min duration: first, using supramolecular solvent; second, with water and vortex; and third, with water assisted by ultrasound. Water extraction assisted by ultrasound at room temperature yielded the greatest quantity of chlorogenic acid and caffeine, with 1.15 mg CA/g and 0.972 mg Caf/g, respectively. Extraction using supra-solvent leads to a lower content of CA in the supra-phase since it has more affinity for the water-based inferior phase. An environmental assessment using life cycle assessment has been carried out to compare water and supra extraction methods for the manufacture of two different commercial products: a face cream and an eye contour serum. Results show that the type of solvent and the amount of active substance extracted have a great influence on the environmental results. The results presented here are important for companies willing to obtain these active substances at an industrial scale.The authors wish to acknowledge the financial support from the Spanish Ministry of Science and Innovation to the project KAIROS-BIOCIR (PID2019-104925RB-C32). The first author also appreciates the support (2021FI SDUR 00130) from the Secretariat for Universities and Research of the Ministry of Business and Knowledge of the Government of Catalonia and the European Social Fund

    A classical treatment of optical tunneling in plasmonic gaps: extending the quantum corrected model to practical situations

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    The optical response of plasmonic nanogaps is challenging to address when the separation between the two nanoparticles forming the gap is reduced to a few nanometers or even subnanometer distances. We have compared results of the plasmon response within different levels of approximation, and identified a classical local regime, a nonlocal regime and a quantum regime of interaction. For separations of a few Ångstroms, in the quantum regime, optical tunneling can occur, strongly modifying the optics of the nanogap. We have considered a classical effective model, so called Quantum Corrected Model (QCM), that has been introduced to correctly describe the main features of optical transport in plasmonic nanogaps. The basics of this model are explained in detail, and its implementation is extended to include nonlocal effects and address practical situations involving different materials and temperatures of operation.</p

    Face, content, and construct validity of the EndoViS training system for objective assessment of psychomotor skills of laparoscopic surgeons

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    Background The aim of this study is to present face, content, and constructs validity of the endoscopic orthogonal video system (EndoViS) training system and determines its efficiency as a training and objective assessment tool of the surgeons’ psychomotor skills. Methods Thirty-five surgeons and medical students participated in this study: 11 medical students, 19 residents, and 5 experts. All participants performed four basic skill tasks using conventional laparoscopic instruments and EndoViS training system. Subsequently, participants filled out a questionnaire regarding the design, realism, overall functionality, and its capabilities to train hand–eye coordination and depth perception, rated on a 5-point Likert scale. Motion data of the instruments were obtained by means of two webcams built into a laparoscopic physical trainer. To identify the surgical instruments in the images, colored markers were placed in each instrument. Thirteen motion-related metrics were used to assess laparoscopic performance of the participants. Statistical analysis of performance was made between novice, intermediate, and expert groups. Internal consistency of all metrics was analyzed with Cronbach’s α test. Results Overall scores about features of the EndoViS system were positives. Participants agreed with the usefulness of tasks and the training capacities of EndoViS system (score >4). Results presented significant differences in the execution of three skill tasks performed by participants. Seven metrics showed construct validity for assessment of performance with high consistency levels. Conclusions EndoViS training system has been successfully validated. Results showed that EndoViS was able to differentiate between participants of varying laparoscopic experience. This simulator is a useful and effective tool to objectively assess laparoscopic psychomotor skills of the surgeons

    Acyloxylation of 1,4-Dioxanes and 1,4-Dithianes Catalyzed by a Copper−Iron Mixed Oxide

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    The use of a copper−iron mixed oxide as a heterogeneous catalyst for the efficient synthesis of α-acyloxy-1,4-dioxanes and 1,4-dithianes employing t-butyl peroxyesters is reported. The preparation and characterization of the catalyst are described. The effect of the heteroatoms and a plausible mechanism are discussed. The method is operationally simple and involves low-cost starting materials affording products in good to excellent yields

    Tumoral and normal brain tissue extraction protocol for wide-scope screening of organic pollutants

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    Little is known about the presence of organic pollutants in human brain (and even less in brain tumors). In this regard, it is necessary to develop new analytical protocols capable of identify-ing a wide range of exogenous chemicals in this type of samples (by combining target, suspect and non-target strategies). These methodologies should be robust and simple. This is particularly challenging for solid samples, as reliable extraction and clean-up techniques should be combined to obtain an optimal result. Hence, the present study focuses on the development of an analytical methodology that allows the screening of a wide range of organic chemicals in brain and brain tumor samples. This protocol was based on a solid-liquid extraction based on bead beating, solid-phase extraction clean-up with multi-layer mixed-mode cartridges, reconstitution and LC -HRMS analysis. To evaluate the performance of the extraction methodology, a set of 66 chemicals (e.g., pharmaceuticals, biocides, or plasticizers, among others) with a wide range of physicochemical properties was employed. Quality control parameters (i.e., linear range, sensitivity, matrix effect (ME%), and recoveries (R%)) were calculated and satisfactory results were obtained for them (e.g., R% within 60-120% for 32 chemicals, or ME% higher than 50% (signal suppression) for 79% of the chemicals)
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