166 research outputs found

    Regional versus global finite-state error repair

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    [Abstract] We focus on the domain of a regional least-cost strategy in order to illustrate the viability of non-global repair models over finitestate architectures. Our interest is justified by the difficulty, shared by all repair proposals, to determine how far to validate. A short validation may fail to gather sufficient information, and in a long one most of the effort can be wasted. The goal is to prove that our approach can provide, in practice, a performance and quality comparable to that attained by global criteria, with a significant saving in time and space. To the best of our knowledge, this is the first discussion of its kind.Ministerio de Educación y Ciencia; TIN2004-07246-C03-02Ministerio de Educación y Ciencia; HP2002-0081Xunta de Galcia; PGIDIT03SIN30501PRXunta de Galcia; PGIDIT02SIN01

    Dealing with non-termination in DCGs

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    The objective of this paper is to study a practical approach to deal with non-termination in de nite clause grammars. We focus on two problems, loop and cyclic structure detection and representation, maintaining a tight balance between practical e ciency and operational completeness. In order to guarantee the validity of our conclusions, we rst map our study to a common situated framework, where the e ectiveness of each approach will be examined and, later, compared by running experiments.Eje: TeoríaRed de Universidades con Carreras en Informática (RedUNCI

    Dealing with non-termination in DCGs

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    The objective of this paper is to study a practical approach to deal with non-termination in de nite clause grammars. We focus on two problems, loop and cyclic structure detection and representation, maintaining a tight balance between practical e ciency and operational completeness. In order to guarantee the validity of our conclusions, we rst map our study to a common situated framework, where the e ectiveness of each approach will be examined and, later, compared by running experiments.Eje: TeoríaRed de Universidades con Carreras en Informática (RedUNCI

    Descubriendo temas en Twitter sobre el brote del COVID-19 en España

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    [Resumen] En este trabajo, analizamos lo que los usuarios han estado discutiendo en Twitter durante el comienzo de la pandemia causada por el COVID-19. Concretamente, analizamos tres fases diferenciadas de la crisis del COVID-19 en España: el propio tiempo de pre-crisis, el estallido de la enfermedad y el confinamiento. Para llevar esto a cabo, primero recolectamos una gran cantidad de tuits que son preprocesados. A continuación, agrupamos los tuits en distintas temáticas usando un modelo de Latent Dirichlet Allocation, y definimos estrategias generativas y discriminativas para extraer las palabras clave y oraciones más representativas para cada tema. Finalmente, incluimos un exhaustivo análisis cualitativo sobre dichos temas, y cómo estos se corresponden con distintas problemáticas surgidas en España en distintos momentos de la crisis.[Abstract] In this work, we apply topic modeling to study what users have been discussing in Twitter during the beginning of the COVID-19 pandemic. More particularly, we explore the period of time that includes three differentiated phases of the COVID-19 crisis in Spain: the pre-crisis time, the outbreak, and the beginning of the lockdown. To do so, we first collect a large corpus of Spanish tweets and clean them. Then, we cluster the tweets into topics using a Latent Dirichlet Allocation model, and define generative and discriminative routes to later extract the most relevant keywords and sentences for each topic. Finally, we provide an exhaustive qualitative analysis about how such topics correspond to the situation in Spain at different stages of the crisis.MMAT has been partially funded by Barcelona Supercomputing Center (BSC) through the Spanish Plan for advancement of Language Technologies `Plan TL' and the Secretaría de Estado de Digitalización e Inteligencia Artificial (SEDIA). DV is supported by MINECO (TIN2017-85160-C2-1-R), by Xunta de Galicia (ED431C 2020/11), by Centro de Investigación de Galicia `CITIC' (European Regional Development Fund-Galicia 2014-2020 Program, ED431G 2019/01), and by a 2020 Leonardo Grant for Researchers and Cultural Creators from the BBVA FoundationXunta de Galicia; ED431C 2020/11Xunta de Galicia; ED431G 2019/0

    On the Logistical Difficulties and Findings of Jopara Sentiment Analysis

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    [Abstract] This paper addresses the problem of sentiment analysis for Jopara, a code-switching language between Guarani and Spanish. We first collect a corpus of Guarani-dominant tweets and discuss on the difficulties of finding quality data for even relatively easy-to-annotate tasks, such as sentiment analysis. Then, we train a set of neural models, including pre-trained language models, and explore whether they perform better than traditional machine learning ones in this low-resource setup. Transformer architectures obtain the best results, despite not considering Guarani during pre-training, but traditional machine learning models perform close due to the low-resource nature of the problem.DV is supported by a 2020 Leonardo Grant for Researchers and Cultural Creators from the FBBVA. 15 DV also receives funding from MINECO (ANSWER-ASAP, TIN2017-85160-C2-1-R), from Xunta de Galicia (ED431C 2020/11), from Centro de Investigación de Galicia ‘CITIC’, funded by Xunta de Galicia and the European Union (European Regional Development Fund- Galicia 2014-2020 Program) by grant ED431G 2019/01Xunta de Galicia; ED431C 2020/11Xunta de Galicia; ED431G 2019/01https://aclanthology.org/2021.calcs-

    Avaliação Retrospetiva da Reconstrução Oncológica da Cabeça e Pescoço com 114 Retalhos Livres num Centro Oncológico Terciário Português

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    Introduction: The Portuguese experience in microsurgical reconstruction of the head and neck after oncological surgery is scantly described. The primary aim of this study was to characterize the use of microvascular reconstruction after head and neck tumor resection in a Portuguese tertiary oncological centerMaterial and Methods: The authors retrospectively evaluated 114 microvascular free flap procedures performed for head and neck reconstruction after oncological resection in a department of Head and Neck Surgery of a Portuguese tertiary oncological center. Patients were operated on from January 2012 to May 2018. Data on patient demographic features, tumour characteristics, perioperative complications, postoperative aesthetic and functional results, survival time and time to recurrence were extracted. Results: Most tumours mandating microsurgical reconstruction were mucosal squamous cell carcinomas (85%) and were located in the oral region (95.6%). Around 45% of the patients had a T4a tumour and 30% a T2 tumour. Cervical metastases were present in 45.6% of the cases. The radial forearm flap and the fibular flap were the most commonly used microsurgical reconstructive options (58% and 41%, respectively). More than 80% of patients had no post-operative complications. Partial necrosis of the flap occurred in 6.1% of patients, while total flap necrosis occurred in 3.5% of cases. Aesthetic and functional results were considered at least satisfactory in all patients in which the flaps survived. Discussion: This study is by far the largest series of microsurgical head and neck reconstruction after oncological surgery reported by a single tertiary centre in Portugal. Survival and functional benefits are similar to those reported in other large oncological centres in the world. Conclusion: Microvascular reconstruction seems like a reliable treatment option in head and neck oncological surgery at our institution.info:eu-repo/semantics/publishedVersio

    Adenoid cystic carcinoma of the palpebral lobe of the lacrimal gland – case report and literature review

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    Epithelial tumors of the lacrimal gland are rare and usually develop in the orbital lobe. We report the exceedingly rare occurrence of a primary adenoid cystic carcinoma in the palpebral lobe of the lacrimal gland. A 26-year-old female was referred for evaluation of a gradually enlarging mass in the lateral upper eyelid, previously diagnosed as a chalazion. Computed tomography revealed a heterogeneous round lesion anterior to the orbital rim. Excisional biopsy was compatible with an adenoid cystic carcinoma. After excluding distant metastasis, and as the patient refused adjuvant radiotherapy, a second surgical procedure, with wide local excision, was indicated. Follow-up showed no recurrence. This case highlights the importance of performing a thorough clinical examination when diagnosing any lateral upper eyelid mass. A high index of suspicion for malignant tumors of the lacrimal gland should always be maintained, and a complete excision with histological analysis should be preferred whenever possible.info:eu-repo/semantics/publishedVersio

    Dealing with non-termination in DCGs

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    The objective of this paper is to study a practical approach to deal with non-termination in de nite clause grammars. We focus on two problems, loop and cyclic structure detection and representation, maintaining a tight balance between practical e ciency and operational completeness. In order to guarantee the validity of our conclusions, we rst map our study to a common situated framework, where the e ectiveness of each approach will be examined and, later, compared by running experiments.Eje: TeoríaRed de Universidades con Carreras en Informática (RedUNCI

    Political conversations on Twitter in a disruptive scenario: The role of "party evangelists" during the 2015 Spanish general elections

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    "This is an Accepted Manuscript of an article published by Taylor & Francis in The Communication Review on 2019, available online: https://www.tandfonline.com/doi/full/10.1080/10714421.2019.1599642"[EN] During election campaigns, candidates, parties, and media share their relevance on Twitter with a group of especially active users, aligned with a particular party. This paper introduces the profile of ¿party evangelists,¿ and explores the activity and effects these users had on the general political conversation during the 2015 Spanish general election. On that occasion, the electoral expectations were uncertain for the two major parties (PP and PSOE) because of the rise of two emerging parties that were disrupting the political status quo (Podemos and Ciudadanos). This was an ideal situation to assess the differences between the evangelists of established and emerging parties. The paper evaluates two aspects of the political conversation based on a corpus of 8.9 million tweets: the retweet- ing effectiveness, and the sentiment analysis of the overall conver- sation. We found that one of the emerging party¿s evangelists dominated message dissemination to a much greater extent.The present research was supported by the Ministerio de Economia y Competitividad [CSO2013-43960-R] [CSO2016-77331-C2-1-R]. The present research was supported by the Ministerio de Economia y Competitividad, Spain, under Grants CSO2013-43960-R ("2015-2016 Spanish political parties' online campaign strategies") and CSO2016-77331-C2-1-R ("Strategies, agendas and discourse in electoral cybercampaigns: media and citizens"). This work was possible thanks to help received from Emilio Giner in his task of extracting the corpus of tweets and from assistance provided by Mike Thelwall and David Vilares in the use of the SentiStrength application. 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    Studies in the mouse model identify strain variability as a major determinant of disease outcome in Leishmania infantum infection

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    Visceral leishmaniasis is a severe and potentially fatal disease caused by protozoa of the genus Leishmania, transmitted by phlebotomine sandflies. In Europe and the Mediterranean region, L. infantum is the commonest agent of visceral leishmaniasis, causing a wide spectrum of clinical manifestations, including asymptomatic carriage, cutaneous lesions and severe visceral disease. Visceral leishmaniasis is more frequent in immunocompromised individuals and data obtained in experimental models of infection have highlighted the importance of the host immune response, namely the efficient activation of host's macrophages, in determining infection outcome. Conversely, few studies have addressed a possible contribution of parasite variability to this outcome.No funders or funding refered in the paper
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