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Operations on Fixpoint Equation Systems
No full textWe study operations on fixpoint equation systems (FES) over arbitrarycomplete lattices. We investigate under which conditions these operations, suchas substituting variables by their definition, and swapping the ordering ofequations, preserve the solution of a FES. We provide rigorous,computer-checked proofs. Along the way, we list a number of known and newidentities and inequalities on extremal fixpoints in complete lattices
Formalising the Double-Pushout Approach to Graph Transformation
No full textIn this paper, we utilize Isabelle/HOL to develop a formal framework for thebasic theory of double-pushout graph transformation. Our work includes definingessential concepts like graphs, morphisms, pushouts, and pullbacks, anddemonstrating their properties. We establish the uniqueness of derivations,drawing upon Rosens 1975 research, and verify the Church-Rosser theorem usingEhrigs and Kreowskis 1976 proof, thereby demonstrating the effectiveness of ourformalisation approach. The paper details our methodology in employingIsabelle/HOL, including key design decisions that shaped the current iteration.We explore the technical complexities involved in applying higher-order logic,aiming to give readers an insightful perspective into the engaging aspects ofworking with an Interactive Theorem Prover. This work emphasizes the increasingimportance of formal verification tools in clarifying complex mathematicalconcepts
-polarity and algorithmic aspects of polarity variants on cograph superclasses
No full textA graph is said to be an -polar graph if its vertex set admits apartition such that and induce, respectively, a complete-partite graph and the disjoint union of at most complete graphs. Polargraphs and monopolar graphs are defined as - and -polar graphs, respectively, and unipolar graphs are those graphs witha polar partition such that is a clique. The problems of deciding whether an arbitrary graph is a polar graph or amonopolar graph are known to be NP-complete. In contrast, deciding whether agraph is a unipolar graph can be done in polynomial time. In this work we provethat the three previous problems can be solved in linear time on the classes of-sparse and -extendible graphs, generalizing analogous resultspreviously known for cographs. Additionally, we provide finite forbidden subgraph characterizations for-polar graphs on -sparse and -extendible graphs, alsogeneralizing analogous results recently obtained for the class of cographs.Comment: 39 pages, 14 figure
Сестры Бурнашевы и Елизавета Кульман
No full textThe Burnashev cousins distinguished themselves in several types of activities accessible to female members of the educated social classes of the mid-19th century. Sofia (1820-1883) published the journal The Leisure Hour and children’s books, while Ekaterina (1819-1875) and Maria (1817-1861) worked as teachers and translators. For them, the ideal female figure was Elizaveta Kulmann (1808-1825), a talented translator and poet who died prematurely. The cult of this young genius was supported by her teacher, Karl Friedrich von Großheinrich, who wrote a biography of Kulmann, translated by the Burnashevs from german to russian. The image of the young poetessbelongs to the culture of Romanticism, while the cousins were active in the era of the great reforms in women’s education. Kulmann’s biography as a creative personality who did not challenge the foundations of patriarchy and the gender canon was used by the Burnashev cousins to defend their conservative position on women’s issues.Les cousines Bournachev se sont illustrées dans plusieurs types d’activités accessibles aux représentantes féminines des classes sociales éduquées du milieu du XIXe siècle. Sofia (1820-1883) a publié la revue L’Heure du loisir et des livres pour enfants, Ékatérina (1819-1875) était éducatrice et traductrice, Maria (1817-1861) a enseigné et traduit. Pour elles, la personnalité féminine idéale était Élisavéta Kulmann (1808-1825), traductrice et poétesse de talent morte prématurément. Le culte de cette jeune fille de génie a été soutenu par son professeur, Karl Grossheinrich, auteur d’une biographie de Kulmann, traduite par les Bournachev de l’allemand en russe. L’image de la jeune poétesse appartient à la culture du romantisme, tandis que les cousines menaient leurs activités à l’époque des grandes réformes dans le domaine de l’éducation des femmes. La biographie de Kulmann en tant que personnalité créatrice n’empiétant pas sur les fondements du patriarcat et du canon de genre a été utilisée par les cousines Bournachev pour défendre leur position conservatrice sur la question des femmes.Сестры Бурнашевы проявили себя в нескольких видах женской деятельности, доступной для представительниц образованных сословий середины XIX века. Софья (1820-1883) выпускала журнал «Час досуга» и детские книги, Екатерина (1819-1875) была классной дамой и переводчицей, Мария (1817-1861) преподавала и переводила. Идеалом женской личности для сестер была Елизавета Кульман (1808-1825), рано ушедшая из жизни талантливая переводчица и поэтесса. Культ юной гениальности поддерживался ее учителем Карлом Гроссгейнрихом, автором биографии Кульман, переведенной Бурнашевыми с немецкого языка на русский. Образ юной поэтессы принадлежал к культуре романтизма, сестры же осуществляли свою деятельность в эпоху буржуазных реформ в области женского образования. Биография Кульман как творческой личности, не посягавшей на основы патриархата и гендерного канона, использовалась сестрами Бурнашевыми для отстаивания консервативной позиции по женскому вопросу
Accounting for the mechanical response of the cell membrane during the uptake of random nanoparticles
No full textIn order to improve the efficiency of the delivery of cancer treatments to cancer cells, the cellular uptake of nanoparticles (NPs), used as drug delivery systems, is numerically investigated through a mechanical approach. The objective is to optimize the NP's mechanical and geometrical properties to enhance their entry into cancer cells while avoiding benign ones. In previous studies, these properties are modeled as constant during the process of cellular uptake. However, recent observations of the displacement of the membrane's constituents towards the region in the cell membrane where the uptake of the NPs takes place show that the mechanical properties of the membrane vary during this process. Reason for writing The important contribution of adhesion to the wrapping process is already well documented in literature. It is therefore crucial to model this parameter properly as the conclusions made with a constant adhesion model may not be accurate compared to reality. Methodology Based on the existing knowledge on the reaction of membrane constituents to interaction with NPs, a 3-parameter sigmoidal function, accounting for the delay, amplitude, and speed of the reaction, has been used to model the evolution of adhesion. A variance-based sensitivity analysis has then been performed in order to quantify the influence of these parameters on the outputs of the model. Results It was found that the introduction of a variable adhesion tends to alter the predictions of endocytosis of NPs. The contribution of the amplitude and delay is respectively 0.32 and 0.43 times as important as that of the NP's aspect ratio, which is the prominent parameter. The influence of the slope of the transition is the least important parameter and does not appear to contribute to endocytosis. Implications Hence, models of the cellular uptake of NPs should use a variable, instead of constant, adhesion in order a representative as possible of the behavior of the cell membrane. The predictions are different from those obtained using a model with constant adhesion
Qui sont les patients partenaires formés par le DU Art du soin en partenariat avec le patient ?
No full textThis article aims to present the first results of a study regarding the graduates of the DU "Art du Soin en Partenariat avec le Patient" since its creation. It primarily deals with the “Partnership patient” part of the survey and intends to report on how they experiment their assignment, how they cope with the various problems they face in their practice. This work also emphasizes their commitment and motivations which enable them to keep on with their work.Cet article est la présentation des premiers résultats d’une étude sur les patients partenaires et le partenariat patient menée auprès des diplômés du DU Art du soin en partenariat avec le patient depuis sa création. Consacré à l’aspect purement « patients partenaires » de l’enquête, il se donne pour objet d’établir le profil de ces patients partenaires, de rendre compte de leurs missions, des obstacles auxquels ils se trouvent confrontés et des déterminants de leur engagement
Impacts des grands événements sportifs internationaux : points de repères et controverses
No full textParis 2024 aims to establish a new model for sustainable mega-events based on the 2020+5agenda. By placing the Games in the context of an ambitious social project, the organizers areraising hopes in many areas (ecological, economic, social), whereas previous Olympiads andthe large number of unknown factors linked to the bid and then the organization justify caution.The academic literature is characterized by a nuanced approach. Indeed, the currentprominence of the notion of legacy should not obscure decades of scientific research into thecomplexity of each of the dimensions that are supposed to constitute it. This paper offers anarrative literature review on the measurement, analysis, and evaluation of economic, social,tourism and environmental impacts. They are characterized by a degree of complexity and arefraught with counter-intuitive effects that need to be understood in order to grasp the potentialstructuring role of the event on its territory. The aim of this paper is to provide researchers andstudents interested in the impact of sporting events with keys to understanding the issuebecause, despite the methodological difficulties involved, mega-events are valuable indicatorsof the democratic, societal and political dynamics at work in our societies.Paris 2024 ambitionne d’établir un nouveau modèle de grand événement sportif international (GESI) durable en s’appuyant sur l’agenda 2020+5. En plaçant les Jeux sous l’angle d’un projet de société ambitieux, les organisateurs suscitent beaucoup d’espérance sur de nombreuses dimensions (touristiques, économiques, sociales), alors que les précédentes olympiades ainsi que le grand nombre d’inconnues liées à la candidature puis à l’organisation pourrait justifier la prudence. Précisément, la littérature académique se caractérise par une approche nuancée des impacts des événements sportifs. En effet, la prégnance actuelle de la notion d’héritage ne doit pas occulter des décennies de recherche scientifique sur la complexité de chacune des dimensions censées la constituer. Nous proposons ici une revue de littérature de ces travaux qui portent sur la mesure, l’analyse ou l’évaluation des impacts économiques, sociaux, touristiques et environnementaux. Ils se caractérisent par une forme de complexité et sont grevés d’effets contre-intuitifs qui doivent être appréhendés pour saisir le potentiel rôle structurant de l’événement sur son territoire hôte. Cette contribution ambitionne de donner des clefs de compréhension aux chercheurs ou aux étudiants qui s’intéressent à ces questions de l’impact des événements sportifs car malgré les difficultés méthodologiques qui jalonnent cette thématique, les GESI restent de précieux révélateurs des dynamiques démocratiques, sociétales et politiques à l’œuvre dans nos sociétés
Predicting Sustainable Development Goals Using Course Descriptions -- from LLMs to Conventional Foundation Models
No full textWe present our work on predicting United Nations sustainable developmentgoals (SDG) for university courses. We use an LLM named PaLM 2 to generatetraining data given a noisy human-authored course description input as input.We use this data to train several different smaller language models to predictSDGs for university courses. This work contributes to better university leveladaptation of SDGs. The best performing model in our experiments was BART withan F1-score of 0.786.Comment: 3 figures, 2 table
Cohomology and Deformations of left-symmetric Rinehart Algebras
No full textWe introduce a notion of left-symmetric Rinehart algebras, which is ageneralization of a left-symmetric algebras. The left multiplication gives riseto a representation of the corresponding sub-adjacent Lie-Rinehart algebra. Weconstruct left-symmetric Rinehart algebra from O-operators on Lie-Rinehartalgebra. We extensively investigate representations of a left-symmetricRinehart algebras. Moreover, we study deformations of left-symmetric Rinehartalgebras, which is controlled by the second cohomology class in the deformationcohomology. We also give the relationships between O-operators and Nijenhuisoperators on left-symmetric Rinehart algebras.Comment: arXiv admin note: text overlap with arXiv:1710.03749, arXiv:1312.6526, arXiv:1808.01909 by other author
Positivity-hardness results on Markov decision processes
No full textThis paper investigates a series of optimization problems for one-counterMarkov decision processes (MDPs) and integer-weighted MDPs with finite statespace. Specifically, it considers problems addressing termination probabilitiesand expected termination times for one-counter MDPs, as well as satisfactionprobabilities of energy objectives, conditional and partial expectations,satisfaction probabilities of constraints on the total accumulated weight, thecomputation of quantiles for the accumulated weight, and the conditionalvalue-at-risk for accumulated weights for integer-weighted MDPs. Althoughalgorithmic results are available for some special instances, the decidabilitystatus of the decision versions of these problems is unknown in general. Thepaper demonstrates that these optimization problems are inherentlymathematically difficult by providing polynomial-time reductions from thePositivity problem for linear recurrence sequences. This problem is awell-known number-theoretic problem whose decidability status has been open fordecades and it is known that decidability of the Positivity problem would havefar-reaching consequences in analytic number theory. So, the reductionspresented in the paper show that an algorithmic solution to any of theinvestigated problems is not possible without a major breakthrough in analyticnumber theory. The reductions rely on the construction of MDP-gadgets thatencode the initial values and linear recurrence relations of linear recurrencesequences. These gadgets can flexibly be adjusted to prove the variousPositivity-hardness results.Comment: arXiv admin note: text overlap with arXiv:2004.1144