751 research outputs found

    Amperometric detection of triclosan with screen-printed carbon nanotube electrodes modified with Guinea Grass (Panicum maximum) peroxidase

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    Triclosan is a compound with antimicrobial activity broadly used in consumer products. Because of its well documented toxicity, the amount of triclosan present in different products needs to be tightly controlled. This paper outlines a new amperometric sensor for triclosan detection consisting of a screen-printed carbon nanotube electrode (SPCNE) modified w ith Guinea grass peroxidase (GGP). The GGP-modified S PCNE was a ble t o d etect an enhanced electrochemical response of triclosan, unlike the bare SPCNE. The cyclic voltammograms of the GGP-modified SPCNE in a solution of potassium ferrocyanide showed an increase in the current values and linearity between scan rates and oxidation peak currents, suggesting a surface controlled process. The GGP-modified SPCNEs howed an excellent electrocatalytic activity to triclosan oxidation, at a redox potential of 370 mV, in the presence of hydrogen peroxide, exhibiting a linear response between 20 mM to 80 mM and a detection limit of 3 µM. This new amperometry system, based on carbon nanotubes integrated with GGP, becomes a potential tool for environmental analysis and food quality control.Fil: Orduz Navas, Angie Estefany. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina. Universidad Industrial Santander; ColombiaFil: Gutiérrez, Jorge Andres. Universidad Industrial Santander; ColombiaFil: Blanco, Sergio Ismael. Universidad Industrial Santander; ColombiaFil: Castillo, John. Universidad Industrial Santander; Colombi

    NarrowBand IoT Data Transmission Procedures for Massive Machine Type Communications

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    Large-scale deployments of massive Machine Type Communications (mMTC) involve several challenges on cellular networks. To address the challenges of mMTC, or more generally, Internet of Things (IoT), the 3rd Generation Partnership Project has developed NarrowBand IoT (NB-IoT) as part of Release 13. NB-IoT is designed to provide better indoor coverage, support of a massive number of low-throughput devices, with relaxed delay requirements, and lower-energy consumption. NB-IoT reuses Long Term Evolution functionality with simplifications and optimizations. Particularly for small data transmissions, NB-IoT specifies two procedures to reduce the required signaling: one of them based on the Control Plane (CP), and the other on the User Plane (UP). In this work, we provide an overview of these procedures as well as an evaluation of their performance. The results of the energy consumption show both optimizations achieve a battery lifetime extension of more than 2 years for a large range in the considered cases, and up to 8 years for CP with good coverage. In terms of cell capacity relative to SR, CP achieves gains from 26% to 224%, and UP ranges from 36% to 165%. The comparison of CP and UP optimizations yields similar results, except for some specific configurations.This work is partially supported by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund (Projects TIN2013-46223-P, and TEC2016-76795- C6-4-R), and the Spanish Ministry of Education, Culture and Sport (FPU Grant 13/04833)

    El sector de la construcción en el departamento del Cauca: ¿una locomotora de crecimiento en el corto y largo plazo?

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    Context: The theory of economic growth consider that the construction sector boost the level of economic activity in the long-run, especially in emerging economies such as Colombia. Nevertheless, this hypothesis may not be true for intermediate cities such as Popayan, since the economic dynamics are not similar to those of large cities. Method: Initially, an autoregressive distributed lag model (ARDL) and a vector error correction model (VMCE) are implemented to find the long-run relationship; subsequently, a vector autoregressive model (VAR) and an autoregressive model with exogenous variables (VARX) are used to characterise the relationship in the short-run by using economic cycles supported on Kalman Filter. Results: The results showing although the construction sector fosters the economy as Currie (1993c) predicted, this relationship for State of Cauca is significant in the short-run, but not in the long-run. Conclusion: As there is evidence of an opposite causality going from the state GDP to the GDP of construction, we infer that this sector is not leader in the level of economic activity in the State of Cauca.Contexto: La teoría del crecimiento económico ha sostenido que el sector de la construcción es un jalonador del nivel de actividad económica a largo plazo, sobre todo en países emergentes como Colombia. Sin embargo, esta hipótesis podría no ser cierta para ciudades intermedias como Popayán, debido a que las dinámicas económicas no son semejantes a las de ciudades grandes. Método: Inicialmente se implementa un modelo autorregresivo de rezagos distribuidos (ARDL, por su sigla en inglés) y un modelo de corrección del error vectorial (VMCE, por su sigla en inglés) para hallar la relación a largo plazo; posteriormente se utiliza un modelo de vectores autorregresivos (VAR, por su sigla en inglés) y un modelo autorregresivo con variables exógenas (VARX, por su sigla en inglés) para caracterizar la relación en el corto plazo, a través de ciclos económicos con la ayuda del filtro de Kalman. Resultados: Si bien el sector de la construcción jalona la economía, como lo predijo Currie (1993c), esta relación para el Cauca es significativa en el corto plazo, pero no en el largo.  Conclusiones: Se evidencia una causalidad contraria que va desde el producto interno bruto (PIB) departamental hacia el PIB de la construcción; por tanto, se infiere que este sector no es impulsor de la actividad económica en el departamento del Cauca

    Performance Modeling of Softwarized Network Services Based on Queuing Theory with Experimental Validation

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    Network Functions Virtualization facilitates the automation of the scaling of softwarized network services (SNSs). However, the realization of such a scenario requires a way to determine the needed amount of resources so that the SNSs performance requisites are met for a given workload. This problem is known as resource dimensioning, and it can be efficiently tackled by performance modeling. In this vein, this paper describes an analytical model based on an open queuing network of G/G/m queues to evaluate the response time of SNSs. We validate our model experimentally for a virtualized Mobility Management Entity (vMME) with a three-tiered architecture running on a testbed that resembles a typical data center virtualization environment. We detail the description of our experimental setup and procedures. We solve our resulting queueing network by using the Queueing Networks Analyzer (QNA), Jackson’s networks, and Mean Value Analysis methodologies, and compare them in terms of estimation error. Results show that, for medium and high workloads, the QNA method achieves less than half of error compared to the standard techniques. For low workloads, the three methods produce an error lower than 10%. Finally, we show the usefulness of the model for performing the dynamic provisioning of the vMME experimentally.This work has been partially funded by the H2020 research and innovation project 5G-CLARITY (Grant No. 871428)National research project 5G-City: TEC2016-76795-C6-4-RSpanish Ministry of Education, Culture and Sport (FPU Grant 13/04833). We would also like to thank the reviewers for their valuable feedback to enhance the quality and contribution of this wor

    Asymmetric data acquisition system for an endoscopic PET-US detector

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    According to current prognosis studies of pancreatic cancer, survival rate nowadays is still as low as 6% mainly due to late detections. Taking into account the location of the disease within the body and making use of the level of miniaturization in radiation detectors that can be achieved at the present time, EndoTOFPET-US collaboration aims at the development of a multimodal imaging technique for endoscopic pancreas exams that combines the benefits of high resolution metabolic information from time-of- flight (TOF) positron emission tomography (PET) with anatomical information from ultrasound (US). A system with such capabilities calls for an application-specific high-performance data acquisition system (DAQ) able to control and readout data from different detectors. The system is composed of two novel detectors: a PET head extension for a commercial US endoscope placed internally close to the region-of-interest (ROI) and a PET plate placed over the patient's abdomen in coincidence with the PET head. These two detectors will send asymmetric data streams that need to be handled by the DAQ system. The approach chosen to cope with these needs goes through the implementation of a DAQ capable of performing multi-level triggering and which is distributed across two different on-detector electronics and the off-detector electronics placed inside the reconstruction workstation. This manuscript provides an overview on the design of this innovative DAQ system and, based on results obtained by means of final prototypes of the two detectors and DAQ, we conclude that a distributed multi-level triggering DAQ system is suitable for endoscopic PET detectors and it shows potential for its application in different scenarios with asymmetric sources of data

    Una mirada prospectiva de la industria Risaraldense camino a la industria 4.0 : plan tecnológico 2020–2030 Centro de Diseño e Innovación Tecnológico Industrial

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    Se presenta el plan tecnológico del Centro de Diseño e Innovación Tecnológico Industrial del SENA para la vigencia 2002 - 2030. Comprende el análisis y diagnóstico de la industria risaraldense, sus necesidades y tendencias, con enfoque a la industria 4.0. Se provee información para: identificar tecnologías y ocupaciones emergentes que permitan anticipar la definición de perfiles de instructores, determinar requerimientos de modernización de infraestructura física y tecnológica del Centro de formación, actualizar, crear o eliminar programas de formación, establecer el tipo de formación, servicios tecnológicos e innovación que el centro de formación ofrecerá en un horizonte de 10 años e identificar los proyectos y actores estratégicos para el centro de formación.The technological plan of the SENA Industrial Technological Design and Innovation Center for the period 2002-2030 is presented. It includes the analysis and diagnosis of the Risaralda industry, its needs and trends, with a focus on industry 4.0. Information is provided to: identify emerging technologies and occupations that allow anticipating the definition of instructor profiles, determine modernization requirements of the physical and technological infrastructure of the Training Center, update, create or eliminate training programs, establish the type of training, services technology and innovation that the training center will offer over a 10-year horizon and identify projects and strategic actors for the training center.Fase I: análisis y diagnóstico estratégico -- Análisis externo del centro de formación -- Análisis interno del centro de formación -- Seguimiento al plan tecnológico inmediatamente anterior -- Cruce DOFA -- Vigilancia científico -tecnológica y competitiva especialidad energía eléctrica -- Vigilancia científico -tecnológica y competitiva especialidad electrónica y automatización -- Vigilancia científico -tecnológica y competitiva especialidad Mecánica Industrial -- Vigilancia científico -tecnológica y competitiva especialidad Informática, diseño y desarrollo de software -- Vigilancia científico -tecnológica y competitiva especialidad materiales para la industria -- Vigilancia científico -tecnológica y competitiva especialidad Automotor -- Vigilancia científico -tecnológica y competitiva especialidad Textil, confección y diseño -- Vigilancia científico -tecnológica y competitiva especialidad construcción e infraestructura -- Vigilancia científico -tecnológica y competitiva servicios tecnológicos -- Fase II: formulación estratégica -- Mapa de trayectoria tecnológica -- Validación con expertos -- Construcción de escenarios -- Formulación estratégica -- Métodos prospectivos utilizados -- Formulación estratégica -- Fase III: recomendaciones estratégicas -- Recomendaciones estratégicas especialidad energía eléctrica -- Recomendaciones estratégicas especialidad electrónica y automatización -- Recomendaciones estratégicas especialidad mecánica industrial -- Recomendaciones estratégicas especialidad Informática, diseño y desarrollo de software -- Recomendaciones estratégicas especialidad materiales para la industria -- Recomendaciones estratégicas especialidad Automotor -- Recomendaciones estratégicas especialidad Textil, confección y diseño -- Recomendaciones estratégicas especialidad construcción e infraestructura -- Recomendaciones estratégicas Sennova -- Servicios tecnológicos -- Introducción e información general -- Planteamiento de la necesidad u oportunidad -- Objetivos -- Desarrollo de la vigilancia científico-tecnológica -- Resultados de vigilancia tecnológica con base en análisis de patentes -- Identificación de tecnologías y sublíneas tecnológicas -- Comportamiento de los aceros -- Vigilancia normativa y regulatoria -- Vigilancia tecnológica -- Vigilancia competitiva -- Vigilancia comercial -- Resultados -- Conclusiones y recomendacionesna556 página

    The COVID-19 pandemic: a letter to G20 leaders

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    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    Mapping genomic loci implicates genes and synaptic biology in schizophrenia

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    Schizophrenia has a heritability of 60-80%1, much of which is attributable to common risk alleles. Here, in a two-stage genome-wide association study of up to 76,755 individuals with schizophrenia and 243,649 control individuals, we report common variant associations at 287 distinct genomic loci. Associations were concentrated in genes that are expressed in excitatory and inhibitory neurons of the central nervous system, but not in other tissues or cell types. Using fine-mapping and functional genomic data, we identify 120 genes (106 protein-coding) that are likely to underpin associations at some of these loci, including 16 genes with credible causal non-synonymous or untranslated region variation. We also implicate fundamental processes related to neuronal function, including synaptic organization, differentiation and transmission. Fine-mapped candidates were enriched for genes associated with rare disruptive coding variants in people with schizophrenia, including the glutamate receptor subunit GRIN2A and transcription factor SP4, and were also enriched for genes implicated by such variants in neurodevelopmental disorders. We identify biological processes relevant to schizophrenia pathophysiology; show convergence of common and rare variant associations in schizophrenia and neurodevelopmental disorders; and provide a resource of prioritized genes and variants to advance mechanistic studies
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