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IntroductionColorectal cancer (CRC) is one of the main causes of deaths worldwide. Early detection and diagnosis of its precursor lesion, the polyp, is key to reduce its mortality and to improve procedure efficiency. During the last two decades, several computational methods have been proposed to assist clinicians in detection, segmentation and classification tasks but the lack of a common public validation framework makes it difficult to determine which of them is ready to be deployed in the exploration room.MethodsThis study presents a complete validation framework and we compare several methodologies for each of the polyp characterization tasks.ResultsResults show that the majority of the approaches are able to provide good performance for the detection and segmentation task, but that there is room for improvement regarding polyp classification.DiscussionWhile studied show promising results in the assistance of polyp detection and segmentation tasks, further research should be done in classification task to obtain reliable results to assist the clinicians during the procedure. The presented framework provides a standarized method for evaluating and comparing different approaches, which could facilitate the identification of clinically prepared assisting methods.

Polyp segmentation within colonoscopy video frames using deep learning models has the potential to automate colonoscopy screening procedures. This could help improve the early lesion detection rate and in vivo characterization of polyps which could develop into colorectal cancer. Recent state-of-the-art deep learning polyp segmentation models have combined Convolutional Neural Network (CNN) architectures and Transformer Network (TN) architectures. Motivated by the aim of improving the performance of polyp segmentation models and their robustness to data variations beyond those covered during training, we propose a new CNN-TN hybrid model named the FCB-SwinV2 Transformer. This model was created by making extensive modifications to the recent state-of-the-art FCN-Transformer, including replacing the TN branch architecture with a SwinV2 U-Net. The performance of the FCB-SwinV2 Transformer is evaluated on the popular colonoscopy segmentation benchmarking datasets Kvasir-SEG, CVC-ClinicDB and ETIS-LaribPolypDB. Generalizability tests are also conducted to determine if models can maintain accuracy when evaluated on data outside of the training distribution. The FCB-SwinV2 Transformer consistently achieves higher mean Dice and mean IoU scores when compared to other models reported in literature and therefore represents new state-of-the-art performance. The importance of understanding subtleties in evaluation metrics and dataset partitioning are also demonstrated and discussed. Code available: https://github.com/KerrFitzgerald/Polyp_FCB-SwinV2Transformer

El objetivo de esta investigación fue evaluar desde una perspectiva multidimensional la situa­ción actual del transporte público en la ciudad de Ibarra (Ecuador). Se utilizaron datos obte­nidos de la Empresa Pública Movildelnor y del Instituto Ecuatoriano de Estadística y Censos, además de los obtenidos de una encuesta a 391 usuarios de taxi de la ciudad de Ibarra. Los resultados se analizaron mediante el uso de estadística descriptiva y la aplicación de un modelo econométrico, a fin de estimar las variables que inciden en la frecuencia de uso del servicio. Un resultado importante de este estudio es que existe evidencia estadísticamente significativa, según la cual, en el caso evaluado, ser mujer reduce la probabilidad de uso diario del servicio de transporte en taxi. Ello confirma la brecha entre hombres y mujeres en cuanto al acceso a servicios de transporte. Es importante garantizar este acceso que permita reducir la desigual­dad de los grupos vulnerables.

Background and study aims Artificial intelligence is currently able to accurately predict the histology of colorectal polyps. However, systems developed to date use complex optical technologies and have not been tested in vivo. The objective of this study was to evaluate the efficacy of a new deep learning-based optical diagnosis system, ATENEA, in a real clinical setting using only high-definition white light endoscopy (WLE) and to compare its performance with endoscopists. Methods ATENEA was prospectively tested in real life on consecutive polyps detected in colorectal cancer screening colonoscopies at Hospital Clínic. No images were discarded, and only WLE was used. The in vivo ATENEA’s prediction (adenoma vs non-adenoma) was compared with the prediction of four staff endoscopists without specific training in optical diagnosis for the study purposes. Endoscopists were blind to the ATENEA output. Histology was the gold standard. Results Ninety polyps (median size: 5 mm, range: 2–25) from 31 patients were included of which 69 (76.7 %) were adenomas. ATENEA correctly predicted the histology in 63 of 69 (91.3 %, 95 % CI: 82 %–97 %) adenomas and 12 of 21 (57.1 %, 95 % CI: 34 %–78 %) non-adenomas while endoscopists made correct predictions in 52 of 69 (75.4 %, 95 % CI: 60 %–85 %) and 20 of 21 (95.2 %, 95 % CI: 76 %–100 %), respectively. The global accuracy was 83.3 % (95 % CI: 74%–90 %) and 80 % (95 % CI: 70 %–88 %) for ATENEA and endoscopists, respectively. Conclusion ATENEA can accurately be used for in vivo characterization of colorectal polyps, enabling the endoscopist to make direct decisions. ATENEA showed a global accuracy similar to that of endoscopists despite an unsatisfactory performance for non-adenomatous lesions.

To evaluate the putative detrimental effect of Major Depressive Disorder (MDD) on the cognitive impairment associated with Alcohol Dependence (AD), we contrasted the neuropsychological profile and behavioral responses of AD subjects, MDD individuals, and in those with a co-occurring AD-MDD diagnosis (DD). Patients and healthy subjects completed a comprehensive neuropsychological battery and were recorded for P200, P300, and N450 event-related potentials during memory and Stroop tasks. AD subjects exhibited a generalized detrimental neuropsychological performance; in contrast, in MDD individuals, impairment was limited to discrete domains. Notably, the deficits were distinctive in DD cases. A P200 increased amplitude in MDD, a decrease in P300 amplitude in AD, and increased latency of P300 in DD patients were the overt electrophysiological abnormalities identified. Dual patients also exhibited a distinct pattern of behavioral responses, particularly apparent during high-demand cognitive tasks. Specific ERP adjustments were associated with the short-term fluoxetine treatment in DD and MDD subjects; the SSRI also improved altered baseline performance in learning and cognitive flexibility in DD subjects. In conclusion, the neuropsychological and behavioral alterations detected in the co-occurrence of AD-MDD did not seem to be merely the sum of the negative contributions of the independent disorders.

Objetivos: medir la prevalencia e intensidad del dolor agudo en pacientes hospitalizados en el Servicio de Neurocirugía de un Hospital Terciario, utilizando una escala verbal numérica, la Escala Visual Analógica (EVA) para su evaluación. Material y métodos: estudio observacional, transversal, para evaluar el dolor agudo. Se incluyen todos los pacientes ingresados en planta durante noviembre del 2019 y se excluyen aquellos con limitaciones para entender o evaluar el dolor según EVA. Resultados: del total de 120 pacientes ingresados en planta durante el periodo de estudio, son excluidos 40 por no cumplir los criterios de inclusión. Se analizan 80 pacientes que presentan elevada prevalencia de dolor (76,61%), con una puntuación media de 3,47 ± 0.78. De los que refieren dolor, en un 20% es leve, 40% moderado y 40% intenso. Por patologías los valores más elevados corresponden a post-intervención. Los protocolos analgésicos del Hospital se aplicaron en todos los casos y ningún paciente acudió a urgencias por dolor tras el alta hospitalaria. La principal limitación del estudio fue que no en todos los pacientes se recogió adecuadamente la puntuación EVA. Conclusiones: la prevalencia de dolor en una planta de neurocirugía es elevada (76,61%), con unas puntuaciones medias (3-4, dolor moderado) que requieren mejorar nuestras estrategias analgésicas y la medición del mismo. Las enfermedades malignas, de predominio intracraneal, se asociaron con mayor dolor.

En el año 2012, en Chile fue promulgada la ley N° 20.609, estableciendo medidas contra la discriminación, resguardando la integridad y el bienestar de las personas que tengan condiciones distintas o pertenezcan a minorías dentro del país. En el año 2017 fue promulgada la ley N° 21.015, incentivando la inclusión de personas con discapacidad al mundo laboral, estableciendo medidas para que las personas en situación de discapacidad (PeSD) no sean discriminadas, teniendo las mismas oportunidades de capacitación y fomento del empleo. Sin embargo, los estudios y análisis sobre esta temática han sido muy escasos. Por lo anterior, el objetivo principal de la presente investigación es identificar y analizar las prácticas laborales en las grandes empresas públicas y privadas de la ciudad de Arica (Chile), con relación a los casos de discriminación y a la inclusión laboral de personas con discapacidad, desarrollando una interpretación basada en la información recopilada mediante cuestionarios. El cuestionario consideró 52 variables segregadas es ocho campos de evaluación. La medición se centró en la inclusión de personas con discapacidad y la indagación en cuanto a medidas contra la discriminación en el área laboral. Como resultado de la investigación, se obtuvo lo siguiente: en cuanto a la inclusión de personas en situación de discapacidad en el mercado laboral se determinó, que la mayoría de las grandes empresas de Arica, cuentan con las condiciones estructurales para que una persona con discapacidad pueda movilizarse dentro de ella. Sin embargo, un 71% de ellas carecen de políticas, normas y procedimientos; así mismo un 66% de las empresas declara no capacitar a sus colaboradores en temas relacionados a la inclusión. Finalmente, se exponen recomendaciones para enfrentar las debilidades encontradas en las empresas de estudiadas.

The Fifth Generation (5G) mobile networking coupled with Internet of Things (IoT) can provide innovative solutions for a wide range of uses cases. The flexibility of virtualized, softwarized and multi-tenant infrastructures and the high performance promised by 5G technology are key to cope with the deployment of the IoT use cases demanded by various vertical businesses. Such 5G IoT use cases incur challenging Quality of Service (QoS) requirements especially connectivity for millions of IoT devices to achieve massive Machine-Type Communication (mMTC). In addition, network slicing is a key enabling technology in 5G multi-tenant networks to create logical virtualized networks for delivering customised solutions to meet diverse QoS requirements. This work presents a 5G IoT framework with network slicing capabilities able to manage a vast number of heterogeneous IoT network slices dynamically on demand. The proposed solution has been empirically tested and validated in five realistic vertical-oriented IoT use cases. The achieved results demonstrate a excellent stability, isolation and scalability while being able to meet extreme QoS requirements even in the most congested and stressful scenarios.

Identity Management (IdM) systems have traditionally relied on a centralized model prone to privacy, trust, and security problems, like potential massive data breaches or identity spoofing. Identity providers accumulate excessive power that might allow them to become a big brother, analyzing and storing as much data as possible. Users should be able to trust identity providers and manage their personal information straightforwardly without compromising their privacy. The European OLYMPUS project introduces a distributed approach for IdM based on enhanced Attribute-Based Credentials (ABC) that splits the role of Identity Provider to limit their influence and chances to become a unique point of failure. However, the trust relationship between service providers, users, and identity providers is still a gap in those kinds of privacy-preserving ABC systems. Decentralized technologies are an opportunity to break away from the centralized model and propose systems that respect privacy while increasing users’ trust. This paper presents an evolution of the OLYMPUS architecture, maintaining all the privacy features and incorporating distributed ledger technologies to enhance trust and security in online transactions and IdM systems. The proposed system has been implemented, tested, and validated, showing its performance and feasibility to manage user’s identity in a fully privacy-preserving, distributed and reliable way.

With the strong development of the Internet of Things (IoT), the definition of IoT devices’ intended behavior is key for an effective detection of potential cybersecurity attacks and threats in an increasingly connected environment. In 2019, the Manufacturer Usage Description (MUD) was standardized within the IETF as a data model and architecture for defining, obtaining and deploying MUD files, which describe the network behavioral profiles of IoT devices. While it has attracted a strong interest from academia, industry, and Standards Developing Organizations (SDOs), MUD is not yet widely deployed in real-world scenarios. In this work, we analyze the current research landscape around this standard, and describe some of the main challenges to be considered in the coming years to foster its adoption and deployment. Based on the literature analysis and our own experience in this area, we further describe potential research directions exploiting the MUD standard to encourage the development of secure IoT-enabled scenarios.

Despite the latest research efforts to foster mobility and roaming in heterogeneous Low Power Wide Area Networks (LP-WANs) networks, handover roaming of Internet of Things (IoT) devices is not a success mainly due to fragmentation and difficulties to establish trust across different network domains as well as the lack of interoperability of different LP-WANs wireless protocols. To cope with this issue, this paper proposes a novel handover roaming mechanism for Low Range Wide Area Network (LoRaWAN) protocol that relies on the trusted 5G network to perform IoT device's authentication and key management, thereby extending the mobility and roaming capabilities of LoRaWAN to global scale. The proposal enables interoperability between 5G network and LoRaWAN, whereby multi Radio Access Technologies IoT (multi-RAT IoT) devices can exploit both technologies interchangeably, thereby fostering novel IoT mobility and roaming use cases for LP-WANs not experimented so far. Two integration approaches for LoRaWAN and 5G have been proposed, either assuming 5G spectrum connectivity with standard 5G authentication or performing 5G authentication over the LoRaWAN network. The solution has been deployed, implemented and validated in a real and integrated 5G-LoRaWAN testbed, showing its feasibility and security viability.

Internet of Things security is attracting a growing attention from both academic and industry communities. Indeed, IoT devices are prone to various security attacks varying from Denial of Service (DoS) to network intrusion and data leakage. This paper presents a novel machine learning (ML) based security framework that automatically copes with the expanding security aspects related to IoT domain. This framework leverages both Software Defined Networking (SDN) and Network Function Virtualization (NFV) enablers for mitigating different threats. This AI framework combines monitoring agent and AI-based reaction agent that use ML-Models divided into network patterns analysis, along with anomaly-based intrusion detection in IoT systems. The framework exploits the supervised learning, distributed data mining system and neural network for achieving its goals. Experiments results demonstrate the efficiency of the proposed scheme. In particular, the distribution of the attacks using the data mining approach is highly successful in detecting the attacks with high performance and low cost. Regarding our anomaly-based intrusion detection system (IDS) for IoT, we have evaluated the experiment in a real Smart building scenario using one-class SVM. The detection accuracy of anomalies achieved 99.71%. A feasibility study is conducted to identify the current potential solutions to be adopted and to promote the research towards the open challenges.

Software Defined Network (SDN) and Network Function Virtualization (NFV) are bringing many advantages to optimize and automatize security management at the network edge, enabling the deployment of virtual network security functions (VSFs) in MEC nodes, to strengthen the end-to-end security in IoT environments. The benefits could exploit in mobile MEC nodes on-boarded in Unmanned Aerial Vehicles (UAV), as the UAVs would carry on-demand VSFs to particular physical locations. To that aim, this paper proposes a novel NFV/SDN-based zero-touch security management framework for automatic orchestration, configuration and deployment of lightweight VSF in MEC-UAVs, that considers diverse contextual factors, related to both physical and virtual conditions, to optimize the security orchestration. Our solution aims to deploy on-demand VSFs, such as virtual Firewalls (vFirewalls), vProxies, vIDS (Intrusion Detection Systems) and vAAA, to assist during emerging situations in particular physical locations, protecting and optimizing the managed IoT network, as well as replacing or supporting compromised physical devices like IoT gateways. The proposed solution has been implemented, deployed and evaluated in a real testbed with real drones, showing its feasibility and performance.

Background: The incidence of vertebral fractures is high and the new treatment options developed in recent years represent a significant improvement, although they are not without complications. Objectives: The aim of this study was to investigate whether percutaneous vertebral augmentation (PVA) was associated with clinical and radiological subsequent adjacent fractures. Methods: A systematic review and meta-analysis was performed searching on PubMed, EMBASE, Cochrane library, Google Scholar, Web of Science, and ClinicalTrial.gov from the establishment of the database to January 2020. Eligible studies assessing the subsequent adjacent fractures after PVA compared with conservative treatment (CT) were incorporated. The pooled risk ratio (RR) with its 95% confidence intervals (95% CI) was used. Heterogeneity, sensitivity, and publication bias analyses were performed. Results: Twenty-four studies were considered eligible and were included finally. 20/421 patients (4.75%) had clinical subsequent adjacent fractures from the PVA group, and 25/359 patients (6.96%) had from the CT group, and 46/440 patients (10.45%) from the PVA group and 36/444 patients (8.10%) from the CT group had radiological subsequent adjacent fractures. There both had no significant difference between two groups (RR = 0.67, 95%CI: [0.38, 1.19], p = 0.17)/(RR = 1.13, 95% CI: [0.75, 1.70], p = 0.576). However, in fractured vertebrae, number in the PVA group was more than that in the CT group (RR=1.41, 95%CI: [1.03, 1.93], p = 0.03). Conclusion: Collectively, currently available literature provides data showed that PVA did not increase the incidence for subsequent adjacent fractures, no matter it was clinical or radiological fracture. However, PVA may increase the number of fractured vertebrae. Antecedentes: La incidencia de fracturas vertebrales es elevada y las nuevas opciones de tratamiento desarrolladas en los últimos años suponen una mejoría importante, aunque no se encuentran exentas de complicaciones. Objetivos: El objetivo de este estudio fue investigar si el tratamiento vertebral percutáneo se asoció con fracturas en los niveles adyacentes, tanto clínicas como radiológicas, en los controles posteriores. Métodos: Se realizó una revisión sistemática y un metanálisis buscando en PubMed, EMBASE, la biblioteca Cochrane, Google Scholar, Web of Science y ClinicalTrial.gov desde el establecimiento de la base de datos hasta enero de 2020. Se eligieron estudios elegibles que evalúan las fracturas adyacentes posteriores después de PVA en comparación con tratamiento conservador (CT). Se utilizó la razón de riesgo (RR), agrupada con sus intervalos de confianza del 95% (IC del 95%). Se realizaron análisis de heterogeneidad, de sensibilidad y de sesgo de publicación. Resultados: Se consideraron elegibles 24 estudio, que se incluyeron finalmente. Del total de pacientes estudiados, 20/421 pacientes (4.75%) tuvieron fracturas adyacentes clínicas posteriores del grupo PVA, y 25/359 pacientes (6,96%) tuvieron del grupo CT, y 46/440 pacientes (10.45%) del grupo PVA y 36/444 pacientes (8.10 %) del grupo CT tenía fracturas adyacentes radiológicas posteriores. No existieron diferencias significativas entre los dos grupos (RR = 0.67, IC 95%: [0.38, 1.19], p = 0.17) / (RR = 1.13, IC 95%: [0.75, 1.70], p = 0.576). Sin embargo, en las vértebras fracturadas, el número en el grupo PVA fue mayor que en el grupo CT (RR = 1.41, IC 95%: [1.03, 1.93], p = 0.03). Conclusión: Desde un punto de vista general, la literatura actualmente disponible proporciona datos que muestran que el PVA no aumentó la incidencia de fracturas adyacentes posteriores, sin importar si fue una fractura clínica o radiológica. Pero el PVA puede aumentar el número de vértebras fracturadas.

Blockchains offer a decentralized, immutable and verifiable ledger that can record transactions of digital assets, provoking a radical change in several innovative scenarios, such as smart cities, eHealth or eGovernment. However, blockchains are subject to different scalability, security and potential privacy issues, such as transaction linkability, crypto-keys management (e.g. recovery), on-chain data privacy, or compliance with privacy regulations (e.g. GDPR). To deal with these challenges, novel privacy-preserving solutions for blockchain based on crypto-privacy techniques are emerging to empower users with mechanisms to become anonymous and take control of their personal data during their digital transactions of any kind in the ledger, following a Self-Sovereign Identity (SSI) model. In this sense, this paper performs a systematic review of the current state of the art on privacy-preserving research solutions and mechanisms in blockchain, as well as the main associated privacy challenges in this promising and disrupting technology. The survey covers privacy techniques in public and permissionless blockchains, e.g. Bitcoin and Ethereum, as well as privacy-preserving research proposals and solutions in permissioned and private blockchains. Diverse blockchain scenarios are analyzed, encompassing, eGovernment, eHealth, cryptocurrencies, Smart cities, and Cooperative ITS.

Social responsibility derives from citizens’ concern for environmental damage caused by corporations. In Peru, research on Corporate Social Responsibility (CSR) is incipient, especially that related with hotel companies. This study objective is to determine how CSR influences the purchasing behavior of Tacna city hotel guests. We identified both hotel guests valuation and the variables that influenced their purchase decision. To collect information we used interviews, panel of experts, and questionnaires sent out to hotel companies and hotel guests. We found that there is a relationship between hotels’ CRS practices and consumers’ behavior in its economic, ethical, and philanthropic dimension.

The pervasive nature of the Internet of Things (IoT) entails additional threats that compromise the security and privacy of IoT devices and, eventually, the users. This issue is aggravated in constrained IoT devices equipped with minimal hardware resources. Current security and privacy implementations need to be redesigned and implemented maintaining its level of assurance, aiming for this family of devices. To cope with this issue, this paper proposes the first novel attempt to leverage anonymous credential systems (ACSs) to preserve the privacy of autonomous IoT constrained devices. Concretely, we have designed a solution to integrate IBM's identity mixer into constrained IoT ecosystems, endowing the IoT with ACSs' privacypreserving capabilities. The solution has been designed, implemented, and evaluated, proving its feasibility.

The growing availability of mobile devices has lead to an arising development of smart cities services that share a huge amount of (personal) information and data. Without accurate and verified management, they could become severe back-doors for security and privacy. In this paper, we propose a smart city infrastructure able to integrate a distributed privacy-preserving identity management solution based on attribute-based credentials (p-ABC), a user-centric Consent Manager, and a GDPR-based Access Control mechanism so as to guarantee the enforcement of the GDPR’s provisions. Thus, the infrastructure supports the definition of specific purpose, collection of data, regulation of access to personal data, and users’ consents, while ensuring selective and minimal disclosure of personal information as well as user’s unlinkability across service and identity providers. The proposal has been implemented, integrated, and evaluated in a fully-fledged environment consisting of MiMurcia, the Smart City project for the city of Murcia, CaPe, an industrial consent management system, and GENERAL_D, an academic GDPR-based access control system, showing the feasibility.

This paper develops a methodology using business intelligence (data warehouse) and OLAP tools (Online Analytical Processing) to match individuals from a household survey data to a census one. In order to geo-reference the household data, the method takes advantage of the geographical information of the census. Using the 2003 Household Survey and the 2002 Chilean Census of Population and Housing, the average household income is projected to intra-municipality levels and the results are compared to Elbers et al. (2003) methodology. The results show that the proposed methodology allows for taking into account and display the impact of intra-municipality heterogeneity and the spatial interaction among the spatial units.

Este caso tiene como protagonistas a Edith Villalobos y Rosa Ibáñez, ejecutivas del Hostal Family House, quienes deben revisar la información disponible para determinar la conveniencia de ampliar la capacidad de alojamiento, con- siderando la amenaza de nuevos entrantes al sector hotelero de la ciudad de Tacna (Perú), así como la identificación de un nicho de mercado al cual dirigirse, estimar la demanda teniendo en cuenta las diferentes características de los servicios que se ofrecen y la variabilidad de la demanda en diferentes meses del año. Este caso ilustra cómo la deci- sión de realizar una ampliación requiere de un análisis muy profundo que va desde los aspectos económicos y finan- cieros, hasta un análisis estratégico. Las características del producto ofrecido tienen una serie de ventajas, pero, a su vez, significa un estudio detallado de algunas características particulares del servicio.

Se propone utilizar las potencialidades geográficas del escenario de la Laguna de las Peonías como museo natural para la enseñanza de la Geografía Física. La metodología es descriptiva, proyectiva, bajo un diseño de campo, no experimental. Al diagnosticar los “Recursos didácticos”, más del 80% de los encuestados afirma que el docente no utiliza “recursos dirigidos y naturales” en la enseñanza. Respecto al “nivel de conocimiento”, existe debilidad en el dominio del mismo, más del 75% de los estudiantes no acertaron en los indicadores “presencia de albuferas”, “presencia de playas y dunas costeras” y “procesos de sedimentación” de la Laguna de las Peonías. Se diseñó una propuesta de museo natural basado en el escenario de la referida laguna, materializado en una visita guiada que contempla cinco (5) estaciones.

It is proposed to use the geographical potentialities of the Peonies lagoon scenario as a natural museum for the teaching of Physical Geography. The methodology is descriptive, projective, under a field design, not experimental. When diagnosing the «didactic resources», more than 80% of the respondents affirmed that the teacher does not use «directed and natural resources» in teaching. Regarding the «level of knowledge», there is weakness in the domain of the same, more than 75% of students did not succeed in the indicators «presence of lagoons», «presence of beaches and coastal dunes» and «sedimentation processes» of the Peonies lagoon. A proposal for a natural museum was designed based on the scenario of the referred lagoon, materialized in a guided tour that includes five (5) stations.

Existen pocos índices para predecir el desarrollo de la arcada dental aplicados en dentición temporal lo que dificulta el diagnóstico de maloclusiones a temprana edad. Objetivo: Establecer la relación entre las discrepancias transversales y sagitales de las arcadas dentales, mediante índices de Carrea, facial morfológico y masa corporal de niños de 3 a 5 años en hogares infantiles del ICBF del municipio de Mocoa. Materiales y métodos: Se realizó un estudio descriptivo transversal en niños entre 3 y 5 años de hogares infantiles del ICBF, la muestra fue de 70 infantes de 13 jardines del área urbana, seleccionados según los siguientes criterios de inclusión: dentición temporal completa, sin caries interproximal según criterios Ceo-d y consentimiento informado firmado, se determinaron alteraciones sagitales y transversales según el índice de Carrea, talla, peso y biotipo facial para establecer la relación con estos indicadores antropométricos, los datos obtenidos fueron analizados utilizando STATA Versión 12. Resultados: Se examinaron 70 niños entre 3 y 5 años, el 54.3% de sexo femenino, en su mayoría de 4 años (44.3%), un 15.7% se encontraba en sobrepeso, el biotipo facial más frecuente fue Euriprosopo (50%). Conclusiones: Se encontró una relación leve entre las discrepancias transversales y sagitales de las arcadas dentales con los indicadores antropométricos faciales y de IMC en 70 niños entre 3 y los 5 años del ICBF de Mocoa. Se halló una relación de leve a moderada entre el IMC y el biotipo facial (coeficiente de correlación de Spearman 0.35 IC95% (0.12 a 0.54).

Analysis of colonoscopy images plays a significant role in early detection of colorectal cancer. Automated tissue segmentation can be useful for two of the most relevant clinical target applications—lesion detection and classification, thereby providing important means to make both processes more accurate and robust. To automate video colonoscopy analysis, computer vision and machine learning methods have been utilized and shown to enhance polyp detectability and segmentation objectivity. This paper describes a polyp segmentation algorithm, developed based on fully convolutional network models, that was originally developed for the Endoscopic Vision Gastrointestinal Image Analysis (GIANA) polyp segmentation challenges. The key contribution of the paper is an extended evaluation of the proposed architecture, by comparing it against established image segmentation benchmarks utilizing several metrics with cross-validation on the GIANA training dataset. Different experiments are described, including examination of various network configurations, values of design parameters, data augmentation approaches, and polyp characteristics. The reported results demonstrate the significance of the data augmentation, and careful selection of the method’s design parameters. The proposed method delivers state-of-the-art results with near real-time performance. The described solution was instrumental in securing the top spot for the polyp segmentation sub-challenge at the 2017 GIANA challenge and second place for the standard image resolution segmentation task at the 2018 GIANA challenge.

The distribution of Internet of Things (IoT) devices in remote areas and the need for network resilience in such deployments is increasingly important in smart spaces covering scenarios, such as agriculture, forest, coast preservation, and connectivity survival against disasters. Although Low-Power Wide Area Network (LPWAN) technologies, like LoRa, support high connectivity ranges, communication paths can suffer from obstruction due to orography or buildings, and large areas are still difficult to cover with wired gateways, due to the lack of network or power infrastructure. The proposal presented herein proposes to mount LPWAN gateways in drones in order to generate airborne network segments providing enhanced connectivity to sensor nodes wherever needed. Our LoRa-drone gateways can be used either to collect data and then report them to the back-office directly, or store-carry-and-forward data until a proper communication link with the infrastructure network is available. The proposed architecture relies on Multi-Access Edge Computing (MEC) capabilities to host a virtualization platform on-board the drone, aiming at providing an intermediate processing layer that runs Virtualized Networking Functions (VNF). This way, both preprocessing or intelligent analytics can be locally performed, saving communications and memory resources. The contribution includes a system architecture that has been successfully validated through experimentation with a real test-bed and comprehensively evaluated through computer simulation. The results show significant communication improvements employing LoRa-drone gateways when compared to traditional fixed LoRa deployments in terms of link availability and covered areas, especially in vast monitored extensions, or at points with difficult access, such as rugged zones.

IoT systems can be leveraged by Network Function Virtualization (NFV) and Software-Defined Networking (SDN) technologies, thereby strengthening their overall flexibility, security and resilience. In this sense, adaptive and policy-based security frameworks for SDN/NFV-aware IoT systems can provide a remarkable added value for self-protection and self-healing, by orchestrating and enforcing dynamically security policies and associated Virtual Network Functions (VNF) or Virtual network Security Functions (VSF) according to the actual context. However, this security orchestration is subject to multiple possible inconsistencies between the policies to enforce, the already enforced management policies and the evolving status of the managed IoT system. In this regard, this paper presents a semantic-aware, zero-touch and policy-driven security orchestration framework for autonomic and conflict-less security orchestration in SDN/NFV-aware IoT scenarios while ensuring optimal allocation and Service Function Chaining (SFC) of VSF. The framework relies on Semantic technologies and considers the security policies and the evolving IoT system model to dynamically and formally detect any semantic conflict during the orchestration. In addition, our optimized SFC algorithm maximizes the QoS, security aspects and resources usage during VSF allocation. The orchestration security framework has been implemented and validated showing its feasibility and performance to detect the conflicts and optimally enforce the VSFs.

Despite the advantages that the Internet of Things (IoT) will bring to our daily life, the increasing interconnectivity, as well as the amount and sensitivity of data, make IoT devices an attractive target for attackers. To address this issue, the recent Manufacturer Usage Description (MUD) standard has been proposed to describe network access control policies in the manufacturing phase to protect the device during its operation by restricting its communications. In this paper, we define an architecture and process to obtain and enforce the MUD restrictions during the bootstrapping of a device. Furthermore, we extend the MUD model with a flexible policy language to express additional aspects, such as data privacy, channel protection, and resource authorization. For the enforcement of such enriched behavioral profiles, we make use of Software Defined Networking (SDN) techniques, as well as an attribute-based access control approach by using authorization credentials and encryption techniques. These techniques are used to protect devices’ data, which are shared through a blockchain platform. The resulting approach was implemented and evaluated in a real scenario, and is intended to reduce the attack surface of IoT deployments by restricting devices’ communication before they join a certain network.

Privacy enhancing technologies (PETs) allow to achieve user’s transactions unlinkability across different online Service Providers. However, current PETs fail to guarantee unlinkability against the Identity Provider (IdP), which becomes a single point of failure in terms of privacy and security, and therefore, might impersonate its users. To address this issue, OLYMPUS EU project establishes an interoperable framework of technologies for a distributed privacy-preserving identity management based on cryptographic techniques that can be applied both to online and offline scenarios. Namely, distributed cryptographic techniques based on threshold cryptography are used to split up the role of the Identity Provider (IdP) into several authorities so that a single entity is not able to impersonate or track its users. The architecture leverages PET technologies, such as distributed threshold-based signatures and privacy attribute-based credentials (p-ABC), so that the signed tokens and the ABC credentials are managed in a distributed way by several IdPs. This paper describes the Olympus architecture, including its associated requirements, the main building blocks and processes, as well as the associated use cases. In addition, the paper shows how the Olympus oblivious architecture can be used to achieve privacy-preserving M2M offline transactions between IoT devices.

As we get into the Internet of Things era, security and privacy concerns remain as the main obstacles in the development of innovative and valuable services to be exploited by society. Given the Machine-to-Machine (M2M) nature of these emerging scenarios, the application of current privacy-friendly technologies needs to be reconsidered and adapted to be deployed in such global ecosystem. This work proposes different privacy-preserving mechanisms through the application of anonymous credential systems and certificateless public key cryptography. The resulting alternatives are intended to enable an anonymous and accountable access control approach to be deployed on large-scale scenarios, such as Smart Cities. Furthermore, the proposed mechanisms have been deployed on constrained devices, in order to assess their suitability for a secure and privacy-preserving M2M-enabled Internet of Things.

The objective of this research was to study the relationship between the fatty acid content and the altitude of orchards and fruit maturity stage of avocados (Persea americana Mill. cv. Hass) at different locations in the department of Antioquia (Colombia). Orchards between 1,340 and 2,420 m a.s.l. were selected and the fatty acid profile and content of the fruits were analyzed. Oleic acid showed the highest percentage for all of the locations and its percentage decreased drastically at lower altitudes, meanwhile the percentage of palmitoleic and linoleic acids increased in these orchards. The oleic/palmitoleic, linoleic/palmitoleic, and oleic/linoleic indexes increased significantly at higher altitudes. Palmitoleic acid increased significantly with the maturity stage (dry matter content) of the avocados for all of the locations. Some fatty acids showed a high linear correlation with the fruit maturity stage, varying the type of acid or index with altitude. The fatty acid content is a variable to consider in future studies for a protected designation of origin (PDO), due to the close relationship observed with the geographical growing area and its importance to human health. More assessments must be taken over the course of years and harvests with more contrasting environments in order to obtain more robust information and feed the model.

El caso describe la situación que enfrenta fray Ernesto (director del Museo del Convento San Francisco de la ciudad de Cusco), producto de los altos costos operacionales del museo bajo su cargo y la poca visita de turistas. Además, se presenta la disyuntiva de Sadith Paz (jefa del proyecto), quien debe proponer un plan de marketing. El caso requiere analizar no solo el mercado y la organización, sino que, además, se deben estudiar las sugerencias que entregaron los intermediarios turísticos (agencias), para poder plantear nuevas estrategias de marketing que permitan mejorar el ser- vicio que brinda actualmente el museo, aparte de los problemas que generaría la exposición y la presencia de turis- tas dentro del convento. Las propuestas de solución no solo se basan en lo comúnmente usado para este tipo de casos, sino en explorar las particularidades de la organización en favor de la experiencia del turista, ofreciendo no solo un momento de descubrimiento, asombro y cultura, sino la posibilidad de experimentar la sensación de ser uno más en la vocación de estos sacerdotes.

El proceso de tomar una decisión financiera, parte del supuesto de que cada una de las acciones que se planifiquen o discutan involucra dos aspectos: la maximización de utilidades y la reducción de costos. Por esto, se supone que dichas decisiones son enteramente racionales. Aquí nace la interrogante principal: ¿las personas toman decisiones racionales, no dejándose influenciar por factores conductuales que afectan la calidad de la decisión y su resultado? Por lo anterior, se busca determinar si las decisiones financieras que se toman en las empresas familiares son racionales y por tanto responden a una jerarquía de preferencia en la utilización de recursos financieros (Pecking Order Theory), o existen factores conductuales que realmente afectan la decisión. El estudio realizado es de diseño transeccional y de tipo relacional. Se consideró una muestra de 58 gerentes de empresas familiares del sector comercial de la región de Tacna (Perú), que contaban con una planilla superior a 20 trabajadores y por lo menos 10 años de actividad. La investigación permitió concluir que el factor optimismo no tiene relación con las decisiones financieras, pero el factor confianza si tiene una relación media con las decisiones financieras. Se concluye, que los individuos que tienen relación con las decisiones de financiamiento de las empresas comerciales de la región, prefieren el financiamiento interno, a través del financiamiento por recursos propios, la reinversión de las utilidades retenidas y por tanto, la preferencia de capitalizarlas en lugar de repartir dividendos entre los socios.

The fourth industrial revolution is being mainly driven by the integration of Internet of Things (IoT) technologies to support the development lifecycle of systems and products. Despite the well-known advantages for the industry, an increasingly pervasive industrial ecosystem could make such devices an attractive target for potential attackers. Recently, the Manufacturer Usage Description (MUD) standard enables manufacturers to specify the intended use of their devices, thereby restricting the attack surface of a certain system. In this direction, we propose a mechanism to manage securely the obtaining and enforcement of MUD policies through the use of a Software-Defined Network (SDN) architecture. We analyze the applicability and advantages of the use of MUD in industrial environments based on our proposed solution, and provide an exhaustive performance evaluation of the required processes.

The increase of Software Defined Networks (SDN) and Network Function Virtualization (NFV) technologies is bringing many security management benefits that can be exploited at the edge of Internet of Things (IoT) networks to deal with cyber-threats. In this sense, this paper presents and evaluates a novel policy-based and cyber-situational awareness security framework for continuous and dynamic management of Authentication, Authorization, Accounting (AAA) as well as Channel Protection virtual security functions in IoT networks enabled with SDN/NFV. The virtual AAA, including network authenticators, are deployed as VNF (Virtual Network Function) dynamically at the edge, in order to enable scalable device’s bootstrapping and managing the access control of IoT devices to the network. In addition, our solution allows distributing dynamically the necessary crypto-keys for IoT Machine to Machine (M2M) communications and deploy virtual Channel-protection proxys as VNFs, with the aim of establishing secure tunnels among IoT devices and services, according to the contextual decisions inferred by the cognitive framework. The solution has been implemented and evaluated, demonstrating its feasibility to manage dynamically AAA and channel protection in SDN/NFV-enabled IoT scenarios.

Las normas de terminación de oraciones son un recurso valioso para los investigadores interesados en el estudio de los efectos que tiene un contexto sobre los procesos de reconocimiento de palabras, y la comprensión del lenguaje en general. Este estudio presenta las normas de terminación para la palabra final de 278 oraciones en español para niños mexicanos, obtenidas a través del método de cloze, en una muestra de 420 estudiantes (226 niños y 194 niñas) de 9 a 12 años de edad del 4º al 6º grado de primarias públicas del Estado de México. La tarea de los niños consistió en leer cada una de las oraciones y completarlas con una palabra al cierre. Se calculó la probabilidad de cierre de cada palabra respondida para cada uno de los contextos, de acuerdo a las respuestas de los niños. Aunque el corpus incluyó oraciones con diferentes restricciones contextuales, la respuesta de los sujetos mostró un mayor número de oraciones con alta probabilidad de cierre. Este material puede ser utilizado en la investigación sobre la comprensión del lenguaje tanto auditivo como escrito en niños.

Colorectal cancer is the fourth most common cause of cancer death worldwide and its survival rate depends on the stage in which it is detected on hence the necessity for an early colon screening. There are several screening techniques but colonoscopy is still nowadays the gold standard, although it has some drawbacks such as the miss rate. Our contribution, in the field of intelligent systems for colonoscopy, aims at providing a polyp localization and a polyp segmentation system based on a model of appearance for polyps. To develop both methods we define a model of appearance for polyps, which describes a polyp as enclosed by intensity valleys. The novelty of our contribution resides on the fact that we include in our model aspects of the image formation and we also consider the presence of other elements from the endoluminal scene such as specular highlights and blood vessels, which have an impact on the performance of our methods. In order to develop our polyp localization method we accumulate valley information in order to generate energy maps, which are also used to guide the polyp segmentation. Our methods achieve promising results in polyp localization and segmentation. As we want to explore the usability of our methods we present a comparative analysis between physicians fixations obtained via an eye tracking device and our polyp localization method. The results show that our method is indistinguishable to novice physicians although it is far from expert physicians.

El artículo examina el clásico debate sobre los factores que caracterizan la cuestión social. Producto de estas discusiones aparece una amplia gama de textos y posiciones que intentan responder qué significa la cuestión social. Sin embargo, en la actualidad se ha dejado a un lado la respuesta a preguntas tales como: ¿Por qué hay sociedades tan desiguales, como las latinoamericanas?, ¿Cuáles son las causas y los responsables de tan grande desigualdad?, ¿Cuál debe ser la relación entre la libertal, la igualdad, la justicia y la democracia?. Debido a su importancia teórica y política, el artículo expone unas opiniones más o menos ordenadas en los sigueintes sentidos: ¿Cuál es hoy, principalmente, la cuestiíon social, y cuál debe ser la agenda más adecuada para su tratamiento?. Palabras Clave: Cuestión social, Desigualdad, Libertad, Neoliberalismo, Izquierda, Derecha ABSTRACT SOCIAL ISSUES AND THE REDISTRIBUTIVE AGENDA The article examines the classic debate about the factors that characterize the social question. Product of these discussions have emerged a wide range of texts and positions which means trying to answer the social question. However, the present debate has left out the answer to questions like: ¿why there are so unequal societies such as the Latin American ones? What are tha causes and the perpetrators of such great inequality? What policies and resources are available to reduce these levels of inequality? What should be the relationship between freedom, equality, justice and democracy? Because of its theoretical and political importance, this paper presents some opinions more or less ordered in the following ways: what is the socual question today, and what should be the most appropiate schedule for its treatment. Key Words: Social issue, Inequality, Freedom, Neoliberalism, Left, Right

El tema de Medellín es abordado desde la perspectiva de los indicadores sociales. El autor inicia con unas consideraciones teóricas sobre el problema de la pobreza y la inequidad, para luego describirlo en el Medellín de los últimos años. Finaliza con una propuesta para incidir positivamente en el mejoramiento de los indicadores sociales en la ciudad. Palabras Clave: Indicadores sociales, Pobreza, Inequidad, Lucha, Medellin

Se estudian ciertas soluciones de ecuaciones no lineales que modelan procesos físicos, que tienen semejanzas con estructuras coherentes del tipo de esferas duras, modelo de partículas muy usado en varias ramas de la física. Estas soluciones compactas (gotas, kinks, etcétera.) interactúan entre sí sólo a cortas distancias, porque no poseen colas infinitas como los solitones clásicos.

El carcinoma del conducto tirogloso es una entidad rara. Alrededor de 200 casos han sido reportados desde 1915. Todos los tipos de carcinoma descritos en la glándula tiroides ocurren en los quistes del conducto tirogloso, excepto el carcinoma medular. En este artículo, reportamos 2 nuevos casos de carcinoma papilar originados en un quiste tirogloso. Ambos con una masa en la línea media de crecimiento acelerado como síntoma inicial. Uno de estos tenía extensión a un ganglio linfático submandibular. A esta paciente se le realizó la resección del quiste, tiroidectomía total, vaciamiento ganglionar submandibular bilateral y resección en cuña del hioides. A la otra paciente, con un carcinoma localizado en el ducto, se le realizó un procedimiento de Sistrunk.