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Global Political Ecology

David Saurí i Pujol
2012 Documents d'Anàlisi Geogràfica  
David Saurí Universitat Autònoma de Barcelona Departament de Geografia No es una elección baladí el hecho de que el libro que nos proponemos comentar se abra con una cita de una obra  ... 
doi:10.5565/rev/dag.27 fatcat:cdyapdx2rndltnnndoueetc5hi

An injectable dosimeter for small animal irradiations [article]

Guy Garty, Monica C. Pujol, David J. Brenner
2019 arXiv   pre-print
We have developed a novel in-vivo dosimeter based on glass encapsulated TLD rods. These encapsulated rods can be injected into mice and used for validating doses to an individual mouse in a protracted irradiation scenario where the mouse is free to move in an inhomogenous radiation field. Data from 30 irradiated mice shows a reliable dose reconstruction within 10% of the nominal delivered dose.
arXiv:1904.07311v1 fatcat:kcw46axffjakhn2fezlkvu7h3q

Meisosomes, folded membrane platforms, link the epidermis to the cuticle in C. elegans [article]

Dina Aggad, Shizue Omi, Clara L Essmann, Nicolas Brouilly, Fabrice Richard, Chantal Cazevieille, Kristin A Politi, David D Hall, Jonathan Ewbank, Remy Pujol, Nathalie Pujol
2021 bioRxiv   pre-print
., 2018; Pujol et al., 2008b) .  ...  ., 2020; Pujol et al., 2008a; Taffoni et al., 2020 ).  ... 
doi:10.1101/2021.11.26.470028 fatcat:sd4fxzlywjbf7ch72hq75wwltm

Answering Summation Queries for Numerical Attributes under Differential Privacy [article]

Yikai Wu, David Pujol, Ios Kotsogiannis, Ashwin Machanavajjhala
2019 arXiv   pre-print
In this work we explore the problem of answering a set of sum queries under Differential Privacy. This is a little understood, non-trivial problem especially in the case of numerical domains. We show that traditional techniques from the literature are not always the best choice and a more rigorous approach is necessary to develop low error algorithms.
arXiv:1908.10268v1 fatcat:uer35pyh4rax7oz62zkaww7myi

For intra-articular delivery of chondroitin sulfate

M David-Raoudi, R Mendichi, J P Pujol
2009 Glycobiology  
been recently reinforced by our study showing that CS was also capable of increasing the production of high-molecular-weight hyaluronan by cultured osteoarthritic synovial fibroblasts (Figure 1 ) (David-Raoudi  ... 
doi:10.1093/glycob/cwp069 pmid:19487725 fatcat:h3c35mmtzrawbjaldyxgxrmqia

Data Sharing Practice in Big Data Ecosystems

Laia Pujol Priego, David Osimo, Jonathan Douglas Wareham
2019 Social Science Research Network  
Big data has gained popularity
doi:10.2139/ssrn.3355696 fatcat:ecgbfbwwxnhfdpqlnvtq3szjia

Introducing Sustainability in a Robotic Engineering Degree: A Case Study

Francisco A. Pujol, David Tomás
2020 Sustainability  
This paper describes a group activity concerning the topic of climate change, designed to introduce the concepts of sustainable development into a Robotic Engineering degree. The purpose of this activity was to make students reflect about the impact of their work on the planet as future engineers by asking them to design an environmentally friendly robot that also integrated social and economic aspects, covering the three dimensions of sustainability in this way. Students were surveyed in order
more » ... to study different aspects of their commitment, attitudes, practices, and motivation towards sustainability. In addition to the overall analysis of the survey, three specific studies were carried out with the aim of comparing the responses of different population groups: (i) Students who completed the proposed assignment and students who did not, (ii) female and male students, and (iii) roles played in the assignment. The results of the analysis revealed the high commitment of the students with respect to sustainability, but also a lack of active participation and awareness of their impact as future engineers. The activity was not only a way to introduce sustainability concepts, but in many cases, it also became a motivation for the participants, especially for the female students.
doi:10.3390/su12145574 fatcat:35dnxzdmpbdhneshmguww5xd5q

Online error correcting output codes

Sergio Escalera, David Masip, Eloi Puertas, Petia Radeva, Oriol Pujol
2011 Pattern Recognition Letters  
This article proposes a general extension of the error correcting output codes framework to the online learning scenario. As a result, the final classifier handles the addition of new classes independently of the base classifier used. In particular, this extension supports the use of both online example incremental and batch classifiers as base learners. The extension of the traditional problem independent codings oneversus-all and one-versus-one is introduced. Furthermore, two new codings are
more » ... roposed, unbalanced online ECOC and a problem dependent online ECOC. This last online coding technique takes advantage of the problem data for minimizing the number of dichotomizers used in the ECOC framework while preserving a high accuracy. These techniques are validated on an online setting of 11 data sets from UCI database and applied to two real machine vision applications: traffic sign recognition and face recognition. As a result, the online ECOC techniques proposed provide a feasible and robust way for handling new classes using any base classifier.
doi:10.1016/j.patrec.2010.11.005 fatcat:rrurqwtyn5gxlm5l2v7vueqi4u

Dyadformer: A Multi-modal Transformer for Long-Range Modeling of Dyadic Interactions [article]

David Curto, Albert Clapés, Javier Selva, Sorina Smeureanu, Julio C. S. Jacques Junior, David Gallardo-Pujol, Georgina Guilera, David Leiva, Thomas B. Moeslund, Sergio Escalera, Cristina Palmero
2021 arXiv   pre-print
Personality computing has become an emerging topic in computer vision, due to the wide range of applications it can be used for. However, most works on the topic have focused on analyzing the individual, even when applied to interaction scenarios, and for short periods of time. To address these limitations, we present the Dyadformer, a novel multi-modal multi-subject Transformer architecture to model individual and interpersonal features in dyadic interactions using variable time windows, thus
more » ... llowing the capture of long-term interdependencies. Our proposed cross-subject layer allows the network to explicitly model interactions among subjects through attentional operations. This proof-of-concept approach shows how multi-modality and joint modeling of both interactants for longer periods of time helps to predict individual attributes. With Dyadformer, we improve state-of-the-art self-reported personality inference results on individual subjects on the UDIVA v0.5 dataset.
arXiv:2109.09487v1 fatcat:z5wkafuynjek3ogp2dtssuhnci

Management and Orchestration of Virtual Network Functions via Deep Reinforcement Learning [article]

Joan S Pujol Roig, David M. Gutierrez-Estevez, Deniz Gündüz
2019 arXiv   pre-print
Management and orchestration (MANO) of resources by virtual network functions (VNFs) represents one of the key challenges towards a fully virtualized network architecture as envisaged by 5G standards. Current threshold-based policies inefficiently over-provision network resources and under-utilize available hardware, incurring high cost for network operators, and consequently, the users. In this work, we present a MANO algorithm for VNFs allowing a central unit (CU) to learn to autonomously
more » ... onfigure resources (processing power and storage), deploy new VNF instances, or offload them to the cloud, depending on the network conditions, available pool of resources, and the VNF requirements, with the goal of minimizing a cost function that takes into account the economical cost as well as latency and the quality-of-service (QoS) experienced by the users. First, we formulate the stochastic resource optimization problem as a parameterized action Markov decision process (PAMDP). Then, we propose a solution based on deep reinforcement learning (DRL). More precisely, we present a novel RL approach called, parameterized action twin (PAT) deterministic policy gradient, which leverages an actor-critic architecture to learn to provision resources to the VNFs in an online manner. Finally, we present numerical performance results, and map them to 5G key performance indicators (KPIs). To the best of our knowledge, this is the first work that considers DRL for MANO of VNFs' physical resources.
arXiv:1910.10695v1 fatcat:sfdlx4ivtvgpdnf7oszyfvmlva

Cytogenetically-based biodosimetry after high doses of radiation [article]

Monica Pujol Canadell, Jay R Perrier, Lidia Cunha, Igor Shuryak, Andrew Harken, Guy Garty, David Brenner
2019 bioRxiv   pre-print
Dosimetry is an important tool for triage and treatment planning following any radiation exposure accident, and biological dosimetry, which estimates exposure dose using a biological parameter, is a practical means of determining the specific dose an individual receives. The cytokinesis-blocked micronucleus assay (CBMN) is an established biodosimetric tool to measure chromosomal damage in mitogen stimulated human lymphocytes. The CBMN method is especially valuable for biodosimetry in triage
more » ... ations thanks to simplicity in scoring and adaptability to high throughput automated sample processing systems. While this technique produces dose response data which fit very well to a linear quadratic model for exposures to low linear energy transfer (LET) radiation and for doses up for 5 Gy, limitations to the accuracy of this method arise at larger doses. Resolution at higher doses is limited by the number of cells reaching mitosis. Whereas it would be expected that the yield of micronuclei increases with the dose, in many experiments it has been shown to actually decrease when normalized over the total number of cells. This variation from a monotonically increasing dose response poses a limitation for retrospective dose reconstruction. In this study we modified the standard CBMN assay to increase its resolution following exposures to higher doses of photons or a mixed neutron and photon beam. The assay is modified either through inhibitions of the G2/M and spindle checkpoints with the addition of caffeine and/or ZM447439 (an Aurora kinase inhibitor), respectively to the blood cultures at select times during the assay. Our results showed that caffeine addition improved assay performance for photon up to 10 Gy. This was achieved by extending the assay time from the typical 70 h to just 74 h. Compared to micronuclei yields without inhibitors, addition of caffeine and ZM447439 resulted in improved accuracy in the detection of micronuclei yields up to 10 Gy from photons and 4 Gy of mixed neutrons and photons. When the dose effect curves were fitted to take into account the turnover phenomenon observed at higher doses, best fitting was achieved when the combination of both inhibitors was used. These techniques permit reliable dose reconstruction after high doses of radiation with a method that can be adapted to high throughput automated sample processing systems.
doi:10.1101/647362 fatcat:azfkdg3pqfdabmsd335qxqdpsa

Revisión sistemática de las consecuencias neurobiológicas del abuso sexual infantil

Noemí Pereda, David Gallardo-Pujol
2011 Gaceta Sanitaria  
información del artículo Historia del artículo: Recibido el 13 de septiembre de 2010 Aceptado el 29 de diciembre de 2010 On-line el 5 de marzo de 2011 Palabras clave: Abuso sexual infantil Neurobiología Impactos en la salud Revisión r e s u m e n Objetivos: Los resultados de diversos estudios sugieren la existencia de un período crítico en el desarrollo del individuo en el cual la experiencia de maltrato y abuso sexual puede conllevar cambios neurobiológicos permanentes o muy duraderos,
more » ... o especialmente a la respuesta del eje neuroendocrino hipotálamico-hipofisario-adrenal. El objetivo de este trabajo es ofrecer una revisión actualizada de las principales consecuencias neurobiológicas del abuso sexual infantil. Métodos: Se seleccionaron aquellas publicaciones de enero de 1999 a enero de 2010, en inglés o español, centradas en las consecuencias neurobiológicas relacionadas con la experiencia de abuso sexual infantil mediante las bases de datos Medline, Scopus, Psycinfo y Web of Science. También se examinaron las listas de referencias de estudios publicados acerca de las consecuencias neurobiológicas de la victimización en la infancia. Resultados: Se incluyeron 34 estudios sobre consecuencias neurobiológicas del abuso sexual infantil, de los cuales se extraen alteraciones neuroendocrinas, estructurales, funcionales y neuropsicológicas que afectan a un importante número de víctimas. Conclusiones: Los trabajos que hasta ahora han explorado los efectos neurobiológicos del maltrato muestran que es necesario considerar a éste y al abuso sexual infantil como problemas de salud que afectan a diferentes áreas de la vida de sus víctimas, favoreciendo así el desarrollo de programas de intervención y tratamiento teniendo en cuenta sus múltiples efectos. a b s t r a c t Objective: The results of several studies suggest that there is a critical timeframe during development in which experiences of maltreatment and sexual abuse may lead to permanent or long-lasting neurobiological changes that particularly affect the hypothalamus-pituitary-adrenal axis response. The aim of the present study was to provide an updated review on the main neurobiological consequences of child sexual abuse. Spanish that focused on the neurobiological consequences of child sexual abuse available through Medline, Scopus and Web of Science. We also examined the references in published articles on the consequences of sexual victimization in childhood. Results: In this review we included 34 studies on neurobiological consequences, indicating different kinds of effects, namely: neuroendocrine, structural, functional and neuropsychological consequences, which affect a large number of victims. Conclusions: The existing body of work on the neurobiological consequences of maltreatment shows the need to consider maltreatment and child sexual abuse as health problems that affect different areas of victims' lives, which would in turn favor the development of intervention and treatment programs that take these multiple effects into account. Introducción El abuso sexual ha sido uno de los tipos de maltrato infantil más tardíamente estudiado, si bien su revelación como maltrato frecuente, y con importantes y perdurables efectos psicológicos para * Autora para correspondencia. Correo electrónico: (N. Pereda). sus víctimas, ha dado lugar en las últimas décadas a un notable crecimiento en el interés profesional sobre la detección de estos casos y la intervención posterior con estas víctimas 1 . Estudios nacionales 2 e internacionales 3,4 han constatado la amplia extensión de este problema en el mundo occidental, con una prevalencia que oscila entre un 10% y un 20% de la población 5 . Recientemente se ha producido una especial sensibilidad hacia este tema, tanto por los investigadores como por parte de la sociedad, y se observa un notable esfuerzo e interés de las 0213-9111/$ -see front matter
doi:10.1016/j.gaceta.2010.12.004 pmid:21377250 fatcat:e2nglueblrcxdc4wigncelh3e4

Unveiling the potential of Graph Neural Networks for robust Intrusion Detection [article]

David Pujol-Perich, José Suárez-Varela, Albert Cabellos-Aparicio, Pere Barlet-Ros
2021 arXiv   pre-print
The last few years have seen an increasing wave of attacks with serious economic and privacy damages, which evinces the need for accurate Network Intrusion Detection Systems (NIDS). Recent works propose the use of Machine Learning (ML) techniques for building such systems (e.g., decision trees, neural networks). However, existing ML-based NIDS are barely robust to common adversarial attacks, which limits their applicability to real networks. A fundamental problem of these solutions is that they
more » ... treat and classify flows independently. In contrast, in this paper we argue the importance of focusing on the structural patterns of attacks, by capturing not only the individual flow features, but also the relations between different flows (e.g., the source/destination hosts they share). To this end, we use a graph representation that keeps flow records and their relationships, and propose a novel Graph Neural Network (GNN) model tailored to process and learn from such graph-structured information. In our evaluation, we first show that the proposed GNN model achieves state-of-the-art results in the well-known CIC-IDS2017 dataset. Moreover, we assess the robustness of our solution under two common adversarial attacks, that intentionally modify the packet size and inter-arrival times to avoid detection. The results show that our model is able to maintain the same level of accuracy as in previous experiments, while state-of-the-art ML techniques degrade up to 50% their accuracy (F1-score) under these attacks. This unprecedented level of robustness is mainly induced by the capability of our GNN model to learn flow patterns of attacks structured as graphs.
arXiv:2107.14756v1 fatcat:ealxk4aozreolpasbtsikzahtq

Does the Badal optometer stimulate accommodation accurately?

Mikel Aldaba, Carles Otero, Jaume Pujol, David A. Atchison
2016 Ophthalmic & physiological optics  
Purpose: To study whether the accommodation response to Badal optometer is equivalent to the response for real space targets. Methods: Accommodative responses were measured for 28 young eyes with the WAM-5500 autorefractometer in eight configurations for 0.17 D, 2.0 D and 5.0 D accommodation stimuli. Parameters that might contribute to differences in response were systematically isolated: stimulation method (real space vs Badal targets), field of view, instrument's cover proximity, the looming
more » ... ffect, and the peripheral interposition of objects in depth. Results: Mean accommodative response differences between a natural view configuration and a configuration with a Badal Optometer were 0.50 AE 0.43 D and 0.58 AE 0.53 D for 2.0 D and 5.0 D stimulation, respectively (p < 0.001), with accommodation lags for the latter condition. Of the isolated parameters that might contribute to these differences, varying the interposition of objects in depth affected accommodation response more markedly. Conclusions: It is likely that Badal optometers affect accommodation through a combination of some or all of the studied parameters. We conclude that accommodation response to closed-view Badal optometers is not equivalent to real space target response.
doi:10.1111/opo.12334 pmid:27774618 fatcat:uzxvqmuzw5bqddnqvvbophkwey

Candida parapsilosisCharacterization in an Outbreak Setting

Duncan M. Kuhn, Pranab K. Mukherjee, Thomas A. Clark, Claude Pujol, Jyotsna Chandra, Rana A. Hajjeh, David W. Warnock, David R. Soll, Mahmoud A. Ghannoum
2004 Emerging Infectious Diseases  
Candida parapsilosis is an important non-albicans species which infects hospitalized patients. No studies have correlated outbreak infections of C. parapsilosis with multiple virulence factors. We used DNA fingerprinting to determine genetic variability among isolates from a C. parapsilosis outbreak and from our clinical database. We compared phenotypic markers of pathogenesis, including adherence, biofilm formation, and protein secretion (secretory aspartic protease [SAP] and phospholipase).
more » ... herence was measured as colony counts on silicone elastomer disks immersed in agar. Biofilms formed on disks were quantified by dry weight. SAP expression was measured by hydrolysis of bovine albumin; a colorimetric assay was used to quantitate phospholipase. DNA fingerprinting indicated that the outbreak isolates were clonal and genetically distinct from our database. Biofilm expression by the outbreak clone was greater than that of sporadic isolates (p < 0.0005). Adherence and protein secretion did not correlate with strain pathogenicity. These results suggest that biofilm production plays a role in C. parapsilosis outbreaks.
doi:10.3201/eid1006.030873 pmid:15207060 pmcid:PMC3323144 fatcat:cwa26zkdzrhhldaike7abq4snu
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