1,237 research outputs found

    Heart Rate Extraction from Novel Neck Photoplethysmography Signals.

    Get PDF
    This paper demonstrates for the first time how heart rate (HR) can be extracted from novel neck photoplethysmography (PPG). A novel algorithm is presented, which when tested in neck PPG signals recorded from 9 subjects at different respiratory rates, obtained good precision with respect to gold standard ECG signals. Mean absolute error (MAE), standard deviation error (SDAE) and root-mean-square error (RMSE) resulted in 1.22, 1.54 and 1.98 beats per minute (BPM), respectively. HRneck estimation showed strong correlation (R=0.94) with reference HRECG. Good agreement between both techniques was also demonstrated by Bland-Altman analysis. The bias between mean HR paired differences was -0.16 BPM and 95% limits of agreement (LoA) were (-4.7, 4.4). Comparatively, for widely used finger PPG, errors were slightly smaller (MAE=0.38 BPM, SDAE=0.48 BPM, RMSE=0.62BPM) and the correlation with reference ECG was also very close to 1 (R=0.99). Bias of -0.04 BPM and 95% LoA (-1.5, 1.4), also showed high degree of agreement. However, these findings show the potential the neck could have as an alternative body location for wearable monitors, aiming to reduce the number of sensing sites whilst still providing access to a wide variety of physiological parameters

    Symbolic Power Without Symbolic Violence?

    Get PDF

    Educating English Learners During the Pandemic: Insights from Experts, Advocates, and Practitioners

    Get PDF
    There is a growing body of evidence about the disproportionate impact the pandemic had on English learners (ELs). We sought to capture the complexity of learning conditions for this student population during the COVID-19 pandemic by interviewing 20 EL education leaders. These experts' experiences revealed that while remote learning posed significant challenges to EL education and services, educators improvised, collaborated, and continued to innovate throughout the pandemic. To help EL students moving forward, education leaders on all levels must acknowledge both the struggle and perseverance that shaped their educational experiences during the pandemic

    Throughput and range characterization of IEEE 802.11ah

    Full text link
    The most essential part of Internet of Things (IoT) infrastructure is the wireless communication system that acts as a bridge for the delivery of data and control messages. However, the existing wireless technologies lack the ability to support a huge amount of data exchange from many battery driven devices spread over a wide area. In order to support the IoT paradigm, the IEEE 802.11 standard committee is in process of introducing a new standard, called IEEE 802.11ah. This is one of the most promising and appealing standards, which aims to bridge the gap between traditional mobile networks and the demands of the IoT. In this paper, we first discuss the main PHY and MAC layer amendments proposed for IEEE 802.11ah. Furthermore, we investigate the operability of IEEE 802.11ah as a backhaul link to connect devices over a long range. Additionally, we compare the aforementioned standard with previous notable IEEE 802.11 amendments (i.e. IEEE 802.11n and IEEE 802.11ac) in terms of throughput (with and without frame aggregation) by utilizing the most robust modulation schemes. The results show an improved performance of IEEE 802.11ah (in terms of power received at long range while experiencing different packet error rates) as compared to previous IEEE 802.11 standards.Comment: 7 pages, 6 figures, 5 table

    Joint Access-Backhaul Perspective on Mobility Management in 5G Networks

    Get PDF
    The ongoing efforts in the research development and standardization of 5G, by both industry and academia, have resulted in the identification of enablers (Software Defined Networks, Network Function Virtualization, Distributed Mobility Management, etc.) and critical areas (Mobility management, Interference management, Joint access-backhaul mechanisms, etc.) that will help achieve the 5G objectives. During these efforts, it has also been identified that the 5G networks due to their high degree of heterogeneity, high QoS demand and the inevitable density (both in terms of access points and users), will need to have efficient joint backhaul and access mechanisms as well as enhanced mobility management mechanisms in order to be effective, efficient and ubiquitous. Therefore, in this paper we first provide a discussion on the evolution of the backhaul scenario, and the necessity for joint access and backhaul optimization. Subsequently, and since mobility management mechanisms can entail the availability, reliability and heterogeneity of the future backhaul/fronthaul networks as parameters in determining the most optimal solution for a given context, a study with regards to the effect of future backhaul/fronthaul scenarios on the design and implementation of mobility management solutions in 5G networks has been performed.Comment: IEEE Conference on Standards for Communications & Networking, September 2017, Helsinki, Finlan

    Extracting the jugular venous pulse from anterior neck contact photoplethysmography

    Get PDF
    The jugular venous pulse (JVP) is the reference physiological signal used to detect right atrial and central venous pressure (CVP) abnormalities in cardio-vascular diseases (CVDs) diagnosis. Invasive central venous line catheterization has always been the gold standard method to extract it reliably. However, due to all the risks it entails, novel non-invasive approaches, exploiting distance cameras and lasers, have recently arisen to measure the JVP at the external and internal jugular veins. These remote options however, constraint patients to very specific body positions in front of the imaging system, making it inadequate for long term monitoring. In this study, we demonstrate, for the first time, that reflectance photoplethysmography (PPG) can be an alternative for extracting the JVP from the anterior jugular veins, in a contact manner. Neck JVP-PPG signals were recorded from 20 healthy participants, together with reference ECG and arterial finger PPG signals for validation. B-mode ultrasound imaging of the internal jugular vein also proved the validity of the proposed method. The results show that is possible to identify the characteristic a, c, v pressure waves in the novel signals, and confirm their cardiac-cycle timings in consistency with established cardiac physiology. Wavelet coherence values (close to 1 and phase shifts of ±180°) corroborated that neck contact JVP-PPG pulses were negatively correlated with arterial finger PPG. Average JVP waveforms for each subject showed typical JVP pulses contours except for the singularity of an unknown "u" wave occurring after the c wave, in half of the cohort. This work is of great significance for the future of CVDs diagnosis, as it has the potential to reduce the risks associated with conventional catheterization and enable continuous non-invasive point-of-care monitoring of CVP, without restricting patients to limited postures

    Reversible Nuclear-Lipid-Droplet Morphology Induced by Oleic Acid: A Link to Cellular-Lipid Metabolism

    Get PDF
    Neutral lipidsÐinvolved in many cellular processesÐare stored as lipid droplets (LD), thosemainly cytosolic (cLD) along with a small nuclear population (nLD). nLD could be involved innuclear-lipid homeostasis serving as an endonuclear buffering system that would provide orincorporate lipids and proteins involved in signalling pathways as transcription factors andas enzymes of lipid metabolism and nuclear processes. Our aim was to determine if nLDconstituted a dynamic domain. Oleic-acid (OA) added to rat hepatocytes or HepG2 cells inculture produced cellular-phenotypic LD modifications: increases in TAG, CE, C, and PLcontent and in cLD and nLD numbers and sizes. LD increments were reversed on exclusionof OA and were prevented by inhibition of acyl-CoA synthetase (with Triacsin C) and thuslipid biosynthesis. Under all conditions, nLD corresponded to a small population (2±10%) oftotal cellular LD. The anabolism triggered by OA, involving morphologic and size changeswithin the cLD and nLD populations, was reversed by a net balance of catabolism, uponeliminating OA. These catabolic processes included lipolysis and the mobilization of hydrolyzedFA from the LD to cytosolic-oxidation sites. These results would imply that nLD areactively involved in nuclear processes that include lipids. In conclusion, nLD are a dynamicnuclear domain since they are modified by OA through a reversible mechanism in combinationwith cLD; this process involves acyl-CoA-synthetase activity; ongoing TAG, CE, and PLbiosynthesis. Thus, liver nLD and cLD are both dynamic cellular organelles.Fil: Lagrutta, Lucía Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Montero Villegas, Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Layerenza, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Sisti, Martin Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Garcia, Margarita Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; ArgentinaFil: Ves Losada, Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; Argentin

    Factores de índole interno y externo y su relación en la infracción del delito de robo agravado en la ciudad de Lima, 2020

    Get PDF
    El presente trabajo de investigación tiene como objetivo determinar la relación de factores de índole interno y externo en la infracción del delito de robo a mano armada en la ciudad de Lima, 2020. El robo a mano armada es uno de los delitos con mayor incidencia en la ciudad de Lima, según el Instituto Nacional de Estadística e Informática - INEI en su publicación “Sistema Integrado de Estadísticas de la Criminalidad y Seguridad Ciudadana” se hicieron 33819 denuncias por el delito de robo agravado, lo que representa un 7,3 % de las denuncias de delitos en el año 2018. Los factores de índole interno, según (Alles, 2006) son aquellas características asociadas al individuo en sí y las de índole externo según (Valdés Salmerón, 2014) son las características del medio que rodea al individuo y que genera influencia sobre él. Esta multiplicidad de factores son los que impulsan a algunas personas a cometer crímenes tales como el delito de robo agravado, que según (Código Penal Peruano, 1991) es una modalidad del delito de robo siempre y cuando se cumplan las condiciones establecidas en el artículo 189° del Código, como es el cometido a mano armada o réplica de arma de fuego, pluralidad de agentes para cometer el delito, que el robo se dé por la noche, que se cometa en un inmueble habitado, entre otros, los cuales están especificados en el mencionado artículo. Dentro de las muchas dimensiones que pueda tener, el presente trabajo también enfoca la pobreza, los trastornos psicológicos y el nivel de educación, que son aspectos fundamentales para entender porque ciertas personas tienen predisposición a tener una conducta criminal.The present research work aims to determine the relationship of internal and external factors and the offense of the crime of aggravated robbery in the city of Lima, 2020. Aggravated robbery is one of the crimes with the highest incidence in the city of Lima, according to the INEI in its publication "Integrated System of Crime Statistics and Citizen Security" 33,819 complaints were made for the crime of aggravated robbery, which represents a 7.3% of crime reports in 2018. The factors of an internal nature, according to (Alles, 2006) are those characteristics associated with the individual itself and those of an external nature according to (Valdés Salmerón, 2004) are the characteristics of the environment that surrounds the individual and that generates influence on him. This multiplicity of factors is what drives some people to commit crimes such as the crime of aggravated robbery, which according to the (Peruvian Penal Code, 1991) is a modality of the crime of robbery as long as the conditions established in the article are met. 189 ° of the Code, such as the plurality of agents to commit the crime, that the robbery occurs at night, that it is committed in an inhabited property, among others, which are specified in the aforementioned article. Among the many dimensions that it may have, this work focuses on family relations, poverty, psychological disorders and the level of education, which are fundamental aspects to understand why certain people have a predisposition to criminal behavior. This is a non-experimental, transectional correlational applied research, which was carried out under the quantitative approach applying the survey techniqu
    corecore