13 research outputs found

    Slice allocation and pricing framework for virtualized millimeter wave cellular networks

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    Traditionally, the cellular spectrum is allocated to operators (OPs) through auctions, as ideal mechanisms to discover market prices and allocate scarce resources. Even though spectrum is indeed scarce in sub-6 GHz bands, it becomes abundant in millimeter-wave (mmWave) bands. Interestingly, in that context, it is base station (BS) density which is limiting, and thus a critical factor, due to the outage phenomena in urban environments. Facing BS scarcity is one of the main reasons to foster virtualization techniques aimed at improving utilization and lowering costs. We consider a scenario with an infrastructure provider (InP) owner of a number of BSs and a set of OPs with their users (UEs). We propose a three-phase framework to price network infrastructure slices (NISs) and allocate them to OPs and to efficiently associate UEs with those NISs. The framework stages are: 1) an initial association, 2) a distributed auction mechanism across the BSs to allocate resources to Ops, and 3) a re-association process where the OPs can optimize the NISs they are awarded. The auction incentivizes OPs to bid truthfully and the outcome yields both socially optimal NISs and Vickrey-Clarke-Groves (VCG) prices. For the re-association phase, we propose deterministic and stochastic exchange-matching algorithms and demonstrate their convergence to stable matching and stable-optimal matching, respectively.Ministerio de Economía, Industria y Competitividad | Ref. TEC2016-76465-C2-2-RXunta de Galicia | Ref. GRC 2018/5

    Environmental DNA: A promising factor for tuberculosis risk assessment in multi-host settings

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    [EN] Attaining and maintaining the Official Tuberculosis Free status continues to be a challenge when several domestic and wild hosts contribute to the maintenance of the Mycobacterium tuberculosis complex (MTC). Local tuberculosis hotspots are sometimes identified in cattle in low-prevalence regions. We have, therefore, studied one such hotspot in depth in order to produce an epidemiological diagnosis. Host population size and MTC prevalence were estimated in selected wildlife and in livestock, while on-cattle environmental DNA detection was additionally used as a proxy for risk of exposure at the farm (herd) level. Positive skin test reactors were found on16 of the 24 cattle farms studied in the period 2012-2016. Although all goats tested negative to the skin test during this period, MTC was confirmed in four sheep at slaughter, thus indicating an unknown prevalence of infection in this host species. With regard to wildlife, the prevalence of MTC infection based on culture was 8.8% in the case of wild boar (Sus scrofa), and the only road-killed badger (Meles meles) submitted for culture tested positive. Two criteria were employed to divide the cattle farms into higher or lower risk: tuberculosis testing results and environmental DNA detection. Environmental MTC DNA detection yielded significant differences regarding "use of regional pastures" and "proximity to woodland". This study suggests that on-animal environmental DNA sampling may help when assessing contact risk as regards MTC in livestock at the herd level. This tool opens up new avenues of epidemiological research in complex multi-host settingsSIThis work was supported by the Programa de Tecnologı´as Avanzadas en Vigilancia Sanitaria (TAVS) from the Comunidad de Madrid (ref. S2013/ABI-2747). JMG holds a FPI predoctoral scholarship (BES-2015- 072206), funded by MINECO. This is a contribution to MINECO grant CGL2017-89866 WildDriver and EU-FEDER. This is also a contribution to Valle de Alcudia pilot project SG-2019-02 from PDR-CLM, and to GOSTU project EU-FEADER (AEIAGRI-PNDR-MAPA, ref. 20190020007521). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscrip

    Large expert-curated database for benchmarking document similarity detection in biomedical literature search

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    Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

    New network paradigms for future multihop cellular systems

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    Abstract The high increase in traffic and data rate for future generations of mobile communication systems, with simultaneous requirement for reduced power consumption, makes Multihop Cellular Networks (MCNs) an attractive technology. To exploit the potentials of MCNs a number of new network paradigms are proposed in this thesis. First, a new algorithm for efficient relaying topology control is presented to jointly optimize the relaying topology, routing and scheduling resulting in a two dimensional or space time routing protocol. The algorithm is aware of intercell interference (ICI), and requires coordinated action between the cells to jointly choose the relaying topology and scheduling to minimize the system performance degradation due to ICI. This framework is extended to include the optimization of power control. Both conventional and cooperative relaying schemes are considered. In addition, a novel sequential genetic algorithm (SGA) is proposed as a heuristic approximation to reconfigure the optimum relaying topology as the network traffic changes. Network coding is used to combine the uplink and downlink transmissions, and incorporate it into the optimum bidirectional relaying with ICI awareness. Seeking for a more tractable network model to effectively use context awareness and relying on the latest results on network information theory, we apply a hexagonal tessellation for inner partition of the cell into smaller subcells of radius r. By using only one single topology control parameter (r), we jointly optimize routing, scheduling and power control to obtain the optimum trade-off between throughput, delay and power consumption in multicast MCNs. This model enables high resolution optimization and motivates the further study of network protocols for MCNs. A new concept for route discovery protocols is developed and the trade-off between cooperative diversity and spatial reuse is analyzed by using this model. Finally, a new architecture for MCN is considered where multihop transmissions are performed by a Delay Tolerant Network, and new solutions to enhance the performance of multicast applications for multimedia content delivery are presented. Numerical results have shown that the algorithms suggested in this thesis provide significant improvement with respect to the existing results, and are expected to have significant impact in the analysis and design of future cellular networks.Tiivistelmä Tiedonsiirron ja tiedonsiirtonopeuksien suuri kasvu sekä tehonkulutuksen pieneneminen tulevien sukupolvien matkapuhelinjärjestelmissä tekevät monihyppyiset matkapuhelinverkot houkutteleviksi vaihtoehdoiksi. Tässä työssä esitetään uusia tiedonsiirtoverkkojen paradigmoja monihyppyisten matkapuhelinverkkojen hyödyntämiseksi. Työssä esitellään uusi algoritmi tehokkaaseen releointitopologian hallintaan, joka optimoi yhtäaikaisesti topologian, reitityksen sekä lähetyshetkien ajoituksen ja mahdollistaa tila-aika-reititysprotokollan toteutuksen. Esitetty algoritmi huomioi solujen keskinäishäiriön ja vaaditulla solujen välisellä koordinoidulla hallinnalla saadaan yhdessä valittua topologia ja ajoitus, jotka minimoivat solujen keskinäisistä häiriöistä johtuvan suorituskyvyn heikentymisen. Myöhemmin tätä viitekehystä on laajennettu lisäämällä siihen tehonsäädön optimointi. Työssä on tutkittu sekä perinteisiä että kooperatiivisia releointimenetelmiä. Lisäksi työssä esitetään uusi geneettinen algoritmi heuristiseksi approksimaatioksi verkon liikenteen muutoksen vaatimaan releointitopologian uudelleen järjestelyyn. Työssä tarkastellaan lisäksi verkkokoodausta ylä- ja alasuuntaan tapahtuvan tiedonsiirron yhdistämiseksi sisällyttämällä se solujen keskinäishäiriön huomioivaan kahdensuuntaiseen releointiin. Etsittäessä paremmin mukautuvaa ja kontekstitietoisuutta hyödyntävää verkkomallia, joka käyttää hyväkseen viimeisimpiä verkkojen informaatioteoreettisia tuloksia, voidaan verkon solut pilkkoa pienempiin kuusikulmaisiin alisoluihin. Käyttämällä ainoastaan näiden alisolujen sädettä r voidaan puolestaan verkon reititys, ajoitus ja tehon säätö optimoida yhtäaikaisesti saavuttaen paras mahdollinen kompromissi verkon läpäisyn, viiveen ja tehonkulutuksen välillä. Kehitetty malli mahdollistaa korkean resoluution optimoinnin ja motivoi uusien verkkoprotokollien kehitystä monihyppyisissä matkapuhelinverkoissa. Tätä mallia käyttäen esitellään myös uusi konsepti reitinetsintäprotokollille sekä analysoidaan kooperatiivisen diversiteetin ja tila-avaruudessa tapahtuvan uudelleenkäytön välistä kompromissiratkaisua. Lopuksi työssä tarkastellaan monihyppyisen matkapuhelinverkon uutta arkkitehtuuria, jossa monihyppylähetykset suoritetaan viivesietoisella verkolla ja esitetään uusia ratkaisuja multimediasisällön monilähetysten tehokkuuden parantamiseksi. Työssä saadut tulokset osoittavat, että ehdotetut algoritmit parantavat järjestelmien suorituskykyä verrattuna aiemmin tiedossa olleisiin tuloksiin. Työn tuloksilla voidaan olettaa myös olevan suuri vaikutus tulevaisuuden matkapuhelinverkkojen analysointiin ja suunnitteluun

    Amitriptyline for post-COVID headache: effectiveness, tolerability, and response predictors

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    Producción CientíficaBackground Headache is one of the most frequently reported symptoms in post-COVID patients. The clinical phenotype of COVID-19 headache combines phenotypic features of both tension-type headache (TTH) and migraine. We aimed to assess the efectiveness, side efects and predictors of amitriptyline (AMT) response in a real-world study setting. Methods We performed an observational multicentric study with a retrospective cohort. All consecutive patients with con frmed COVID-19 infection who received AMT for post-COVID headache from March 2020 to May 2021 were included. Response was evaluated by the reduction in the number of headache days per month (HDM) between weeks 8 and 12, compared with the baseline. We explored which variables were associated with a higher probability of response to AMT. Results Forty-eight patients were eligible for the study, 40/48 (83.3%) females, aged 46.85 (SD: 13.59) years. Patients had history of migraine 15/48 (31.3%) or TTH 5/48 (10.4%). The mean reduction of HDM was 9.6 (SD: 10.9; 95% CI 6.5, 12.7) days. Only 2/48 (5%) of patients discontinued AMT due to poor tolerability. History of TTH (10.9, 95% CI 1.3, 20.6) and nausea (−8.5, 95% CI −14.6, −2.5) were associated with AMT response. Conclusions This study provides real-world evidence of the potential beneft of AMT in patients with post-COVID-19 headache, especially in patients with history of TTH and without concomitant nausea.Ministerio de Economía y Competitividad (Instituto de Salud Carlos III) & Unión Europea (Fondo Social Europeo, FSE+) a través del Río Hortega Beca (CM21/00178)Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

    Environmental DNA: A promising factor for tuberculosis risk assessment in multi-host settings

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    Attaining and maintaining the Official Tuberculosis Free status continues to be a challenge when several domestic and wild hosts contribute to the maintenance of the Mycobacterium tuberculosis complex (MTC). Local tuberculosis hotspots are sometimes identified in cattle in low-prevalence regions. We have, therefore, studied one such hotspot in depth in order to produce an epidemiological diagnosis. Host population size and MTC prevalence were estimated in selected wildlife and in livestock, while on-cattle environmental DNA detection was additionally used as a proxy for risk of exposure at the farm (herd) level. Positive skin test reactors were found on16 of the 24 cattle farms studied in the period 2012–2016. Although all goats tested negative to the skin test during this period, MTC was confirmed in four sheep at slaughter, thus indicating an unknown prevalence of infection in this host species. With regard to wildlife, the prevalence of MTC infection based on culture was 8.8% in the case of wild boar (Sus scrofa), and the only road-killed badger (Meles meles) submitted for culture tested positive. Two criteria were employed to divide the cattle farms into higher or lower risk: tuberculosis testing results and environmental DNA detection. Environmental MTC DNA detection yielded significant differences regarding “use of regional pastures” and “proximity to woodland”. This study suggests that on-animal environmental DNA sampling may help when assessing contact risk as regards MTC in livestock at the herd level. This tool opens up new avenues of epidemiological research in complex multi-host settings.This work was supported by the Programa de Tecnologias Avanzadas en Vigilancia Sanitaria (TAVS) from the Comunidad de Madrid (ref. S2013/ABI-2747). JMG holds a FPI predoctoral scholarship (BES-2015- 072206), funded by MINECO. This is a contribution to MINECO grant CGL2017-89866 WildDriver and EU-FEDER. This is also a contribution to Valle de Alcudia pilot project SG-2019-02 from PDR-CLM, and to GOSTU project EU-FEADER (AEIAGRI-PNDR-MAPA, ref. 20190020007521).Peer reviewe

    Aprender no es aburrido

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    Este proyecto pretende fomentar el interés de los alumnos por el aprendizaje y que adquieran los conceptos mínimos de las distintas materias que componen el currículo de ESO. A la vez, se trabajan las destrezas básicas y las técnicas de estudio a través de juegos. Cada grupo elabora un juego de mesa de preguntas y respuestas y diseñan ellos mismos el tablero y las reglas del juego. Estos juegos se intercambian entre los distintos grupos y se usan para repasar los contenidos de las asignaturas. Además se realiza un juego que consiste en tres pruebas individuales de conocimientos y dos pruebas colectivas de investigación que permiten a cada clase ir sumando puntos. La clase que queda primera gana una excursión. El proyecto ha recibido una gran acogida por parte del alumnado que se ha esforzado por trabajar en equipo, y también ha recibido una valoración muy positiva por parte del profesorado que considera que ha incidido positivamente en los resultados académicos de los alumnos. El proyecto adjunta tres CD-ROM con el juego de Historia del Arte de segundo de Bachillerato, Educación Física de primero de Bachillerato y de memoria visual; y un anexo con la lista de materiales elaborados y fotografías del desarrollo de la experiencia.Madrid (Comunidad Autónoma). Consejería de Educación. Dirección General de Ordenación AcadémicaMadridMadrid (Comunidad Autónoma). Subdirección General de Formación del Profesorado. CRIF Las Acacias; General Ricardos 179 - 28025 Madrid; Tel. + 34915250893ES

    Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

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    © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit
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