1,286 research outputs found

    Nominal Unification from a Higher-Order Perspective

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    Nominal Logic is a version of first-order logic with equality, name-binding, renaming via name-swapping and freshness of names. Contrarily to higher-order logic, bindable names, called atoms, and instantiable variables are considered as distinct entities. Moreover, atoms are capturable by instantiations, breaking a fundamental principle of lambda-calculus. Despite these differences, nominal unification can be seen from a higher-order perspective. From this view, we show that nominal unification can be reduced to a particular fragment of higher-order unification problems: Higher-Order Pattern Unification. This reduction proves that nominal unification can be decided in quadratic deterministic time, using the linear algorithm for Higher-Order Pattern Unification. We also prove that the translation preserves most generality of unifiers

    The Complexity of 3-Valued Lukasiewicz Rules

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    It is known that determining the satisfiability of n-valued Łukasiewicz rules is NP-complete for n ≥ 4, as well as that it can be solved in time linear in the length of the formula in the Boolean case (when n = 2). However, the complexity for n = 3 is an open problem. In this paper we formally prove that the satisfiability problem for 3-valued Łukasiewicz rules is NP-complete. Moreover, we also prove that when the consequent of the rule has at most one element, the problem is polynomially solvable. © Springer International Publishing Switzerland 2015.Research partially supported by the Generalitat de Catalunya grant AGAUR 2014-SGR-118, and the Ministerio de Economía y Competividad projects AT CONSOLIDER CSD2007-0022, INGENIO 2010, CO-PRIVACY TIN2011-27076-C03-03, EDETRI TIN2012-39348-C02-01 and HeLo TIN2012-33042. The second author was supported by Mobility Grant PRX14/00195 of the Ministerio de Educación, Cultura y DeportePeer reviewe

    Higher-Order Pattern Anti-Unification in Linear Time

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    We present a rule-based Huet’s style anti-unification algorithm for simply typed lambda-terms, which computes a least general higher-order pattern generalization. For a pair of arbitrary terms of the same type, such a generalization always exists and is unique modulo α-equivalence and variable renaming. With a minor modification, the algorithm works for untyped lambda-terms as well. The time complexity of both algorithms is linear.This research has been partially supported by the Austrian Science Fund (FWF) project SToUT (P 24087-N18), the Upper Austrian Government strategic program “Innovatives OÖ 2010plus”, the MINECO projects RASO (TIN2015-71799-C2-1-P) and HeLo (TIN2012-33042), the MINECO/FEDER UE project LoCoS (TIN2015-66293-R) and the UdG project MPCUdG2016/055.Peer Reviewe

    A Variant of Higher-Order Anti-Unification

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    We present a rule-based Huet's style anti-unification algorithm for simply-typed lambda-terms in η-long -normal form, which computes a least general higher-order pattern generalization. For a pair of arbitrary terms of the same type, such a generalization always exists and is unique modulo α-equivalence and variable renaming. The algorithm computes it in cubic time within linear space. It has been implemented and the code is freely available. © Alexander Baumgartner, Temur Kutsia, Jordi Levy, and Mateu Villaret; licensed under Creative Commons License CC-BY 24th International Conference on Rewriting Techniques and Applications (RTA'13).This research has been partially supported by the projects HeLo (TIN2012-33042) and TASSAT (TIN2010-20967-C04-01), by the Austrian Science Fund (FWF) with the project SToUT (P 24087-N18) and by the Generalitat de Catalunya with the grant AGAUR 2009-SGR-1434.Peer Reviewe

    Sexualité des adolescents et sida: processus et négociations autour des relations sexuelles et du choix de la contraception

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    Cette étude a permis d'explorer, auprès d'adolescents de 16 à 20 ans, l'entrée dans la vie sexuelle et l'utilisation de contraception et de protection vis à vis des maladies sexuellement transmissibles en abordant les perceptions, les attitudes et les croyances qui y sont liées et en étudiant les interactions et les négociations entre les partenaires. Les résultats confirment un certain nombre d'informations déjà disponibles en Suisse et issues d'autres enquêtes auprès des adolescents. Mais ils apportent aussi des indications quelquefois inattendues sur des sujets non encore explorés par la recherche auprès des adolescents. [...] Par rapport à la plupart des enquêtes sur la sexualité des adolescents et la prévention du sida, elle s'attache à considérer les comportements sexuels dans une perspective biographique, à les situer dans leur contexte et à mettre en évidence les aspects relationnels des décisions prises en couple au cours des différentes relations. L'originalité de cette enquête tient d'une part au contenu du questionnaire qui apporte des informations non disponibles en Suisse jusqu'ici et d'autre part aux méthodes utilisées. [P. 5]]]> HIV Infections/prevention &amp; control ; Acquired Immunodeficiency Syndrome/prevention &amp; control; Sex Education ; Sexual Behavior ; Attitude to Health ; Adolescent ; Child ; Program Evaluation ; Condoms/utilization ; Health Knowledge, Attitudes, Practice ; Questionnaires ; Switzerland fre https://serval.unil.ch/resource/serval:BIB_1691.P001/REF.pdf http://nbn-resolving.org/urn/resolver.pl?urn=urn:nbn:ch:serval-BIB_16916 info:eu-repo/semantics/altIdentifier/urn/urn:nbn:ch:serval-BIB_16916 info:eu-repo/semantics/submittedVersion info:eu-repo/semantics/openAccess Copying allowed only for non-profit organizations https://serval.unil.ch/disclaimer application/pdf oai:serval.unil.ch:BIB_16918 2022-05-07T01:11:13Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_16918 Chemitry and Pharmacology of Asian Plants and Validation of Phytopharmaceuticals, Proceedings of the IOCD - International Symposium Chulabhorn, M Hostettmann, K info:eu-repo/semantics/book book 2000 oai:serval.unil.ch:BIB_16919 2022-05-07T01:11:13Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_16919 The Fugu rubripes tyrosinase gene promoter targets transgene expression to pigment cells in the mouse. Camacho-Hübner, A Rossier, A Beermann, F info:eu-repo/semantics/article article 2000 Genesis, vol. 28, pp. 99-105 oai:serval.unil.ch:BIB_1691E41DA533 2022-05-07T01:11:13Z ehelvetica openaire documents phdthesis urnserval <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_1691E41DA533 Methylation of GpG Island promoters in uveal melanoma Moulin, A.-P. Université de Lausanne, Faculté de biologie et médecine info:eu-repo/semantics/doctoralThesis phdthesis 2008 <![CDATA[ABSTRACT : Background: Inactivation of tumour-related genes by promoter hypermethylation is a common epigenetic event in the development of a variety of tumours. Aim: To investigate in primary uveal melanoma the status of promoter methylation of genes thought to be involved in tumour development: p16, TIMP3, RASSF1, RARB, FHIT, hTERT and APC. Methods: Gene promoter methylation was studied by methylation-sensitive single-strand conformation analysis and dot-blot assay in a series of 23 primary uveal melanomas. All DNA samples were obtained from paraffin-embedded formalin-fixed tissue blocks. Results: hTERT promoter methylation was found with a relatively high frequency (52%). Promoter methylation of p16, TIMP3, RASSF1, RARB, FHIT and APC was a rare event. For none of these genes did promoter methylation exceed 15% of tumour samples, and, for some genes (FHIT and APC), no methylation was found at all. Furthermore, promoter methylation was absent in 39% (9/ 23) of cases. In only 22% (5/23) of cases was hypermethylation of at least two promoters observed. Conclusions: Promoter methylation of hTERT is a regular event in uveal melanoma. Hypermethylation of the other genes studied does not seem to be an essential element in the development of this tumour. As promoter methylation of APC, RASSF1 and RARB is often observed in cutaneous melanoma, these results suggest that different epigenetic events occur in the development of cutaneous and uveal melanoma. RAPPORT DE SYNTHESE : L'inactivation de gènes par une hyperméthylation de leur promoteur apparaît être un événement épigénétique fréquent, se retrouvant dans de nombreuses tumeurs. Dans cette étude, nous avons investigué dans des mélanomes primaires de l'uvée l'état de méthylation du promoteur de gènes fréquemment impliqués dans le développent tumoral tels que p16, TIMP3, RASSFI, RARB, FHIT, hTERT et APC. La méthylation des promoteurs de gènes a été étudiée par methylationsensitive single-strand conformation analysis (MS-SSCA) et dot blot assay (MS-DBA) dans une série de 23 mélanomes primaires de l'uvée. Tous les échantillons tissulaires provenaient de matériel fixé dans le formol et conservé dans des blocs de parraffine. Nous avons identifié une fréquence relativement élevée (52%) pour la méthylation du promoteur de hTERT. En ce qui concerne le reste des gènes étudiés, nous avons retrouvé des fréquences de méthylation de promoteurs relativement basses avec 13% pour RASSF1, 13% pour RARB 13%, 9% pour TIMP3 et 4% pour p16. Nous n'avons pas retrouvé d'hyperméthylation des promoteurs des gènes APC et FRIT. La méthylation de hTERT apparaît être un événement important dans la biologie du mélanome de l'uvée. L'hyperméthylation des autres gènes évalués ne semble pas être cruciale dans le développent de cette tumeur. Comme la méthylation des promoteurs des gènes APC, RASSF1 et RARB a été fréquemment observée dans le mélanome de la peau, notre étude tend à démontrer que des mécanismes épigénétiques différents surviennent dans le développement respectif de ces tumeurs

    Endoscopic ultrasonic curette-assisted removal of frontal osteomas

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    Indications for endoscopic resection of fronto-ethmoidal osteomas have been progressively expanded thanks to optimization of surgical exposure and the development of dedicated instruments. Curved cutting drills are still suboptimal to treat hard osseous neoplasms of the frontal sinus. We present two patients affected by frontal osteoma treated with an endoscopic procedure using an ultrasonic bone curette. The ultrasonic bone curette may be considered an effective tool to reduce soft tissue manipulation, optimize surgical time and accelerate the healing process. However, the technique requires significant shape innovations to reach the lateral recesses and to manage pure intrasinusal lesions
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