55 research outputs found

    Galois Theory for H-extensions and H-coextensions

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    We show that there exists a Galois correspondence between subalgebras of an H-comodule algebra A over a base ring R and generalised quotients of a Hopf algebra H. We also show that Q-Galois subextensions are closed elements of the constructed Galois connection. Then we consider the theory of coextensions of H-module coalgebras. We construct Galois theory for them and we prove that H-Galois coextensions are closed. We apply the obtained results to the Hopf algebra itself and we show a simple proof that there is a bijection correspondence between right ideal coideals of H and its left coideal subalgebras when H is finite dimensional. Furthermore we formulate necessary and sufficient conditions when the Galois correspondence is a bijection for arbitrary Hopf algebras. We also present new conditions for closedness of subalgebras and generalised quotients when A is a crossed product.Comment: Left admissibility for subalgebras changed, an assumption added to Theorem 4.7 (A^{op} is H^{op}-Galois) and proof of Theorem 4.7 adde

    Computational Aspects of Extending the Shapley Value to Coalitional Games with Externalities

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    Until recently, computational aspects of the Shapley value were only studied under the assumption that there are no externalities from coalition formation, i.e., that the value of any coalition is independent of other coalitions in the system. However, externalities play a key role in many real-life situations and have been extensively studied in the game-theoretic and economic literature. In this paper, we consider the issue of computing extensions of the Shapley value to coalitional games with externalities proposed by Myerson [21], Pham Do and Norde [23], and McQuillin [17]. To facilitate efficient computation of these extensions, we propose a new representation for coalitional games with externalities, which is based on weighted logical expressions. We demonstrate that this representation is fully expressive and, sometimes, exponentially more concise than the conventional partition function game model. Furthermore, it allows us to compute the aforementioned extensions of the Shapley value in time linear in the size of the input

    A Logic-Based Representation for Coalitional Games with Externalities

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    We consider the issue of representing coalitional games in multiagent systems that exhibit externalities from coalition formation, i.e., systems in which the gain from forming a coalition may be affected by the formation of other co-existing coalitions. Although externalities play a key role in many real-life situations, very little attention has been given to this issue in the multi-agent system literature, especially with regard to the computational aspects involved. To this end, we propose a new representation which, in the spirit of Ieong and Shoham [9], is based on Boolean expressions. The idea behind our representation is to construct much richer expressions that allow for capturing externalities induced upon coalitions. We show that the new representation is fully expressive, at least as concise as the conventional partition function game representation and, for many games, exponentially more concise. We evaluate the efficiency of our new representation by considering the problem of computing the Extended and Generalized Shapley value, a powerful extension of the conventional Shapley value to games with externalities. We show that by using our new representation, the Extended and Generalized Shapley value, which has not been studied in the computer science literature to date, can be computed in time linear in the size of the input

    Perinatal outcome according to chorionicity in twins — a Polish multicenter study

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    Objectives: The aim of the study was to analyze the perinatal outcome of twin gestations and estimate the influence of chorionicity on the outcome in a large cohort of twin pregnancies in Poland. Material and methods: A retrospective analysis of 465 twin deliveries in 6 Polish centers in 2012 was conducted. Baseline characteristics, the course of pregnancy and labor, as well as the neonatal outcome were analyzed in the study group and according to chorionicity. Results: A total of 356 twin pregnancies were dichorionic (DC group) (76.6%), and 109 were monochorionic (MC group) (23.4%). There were no differences in the occurrence of pregnancy complications according to chorionicity, except for IUGR of at least one fetus (MC 43.1% vs. DC 34.6%; p = 0.003). 66.5% of the women delivered preterm, significantly more in the MC group (78% vs. 62.9%; p = 0.004). Cesarean delivery was performed in 432 patients (92.9%). Mean neonatal birthweight was statistically lower in the MC group (2074 g vs. 2370 g; p < 0.001). Perinatal mortality of at least one twin was 4.3% (2.8% in the DC group vs. 9.2% in the MC group; p = 0.004). Neonatal complications, including NICU admission, respiratory disorders, and infections requiring antibiotic therapy, were significantly more often observed among the MC twins. Conclusions: The overall perinatal outcome in the presented subpopulation of Polish twins and its dependence on cho­rionicity is similar to the reports in the literature. Nevertheless, the rates of preterm and cesarean deliveries remain higher. It seems that proper counselling of pregnant women and education of obstetricians may result in reduction of these rates

    Ból i cierpienie

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    Publikacja recenzowana / Peer-reviewed publicationZE WSTĘPU: W tym roku oddajemy do rąk Czytelników szczególnie uroczysty zeszyt cyklicznego wydawnictwa Krakowskiej Szkoły Wyższej „Acta Academiae Modrevianae”, na łamach którego zamieszczamy referaty wygłoszone na jubileuszowej sesji nt. „Ból i cierpienie” w 2007 roku

    Dynamic Modelling of Mental Resilience in Young Adults: Protocol for a Longitudinal Observational Study (DynaM-OBS)

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    Background Stress-related mental disorders are highly prevalent and pose a substantial burden on individuals and society. Improving strategies for the prevention and treatment of mental disorders requires a better understanding of their risk and resilience factors. This multicenter study aims to contribute to this endeavor by investigating psychological resilience in healthy but susceptible young adults over 9 months. Resilience is conceptualized in this study as the maintenance of mental health or quick recovery from mental health perturbations upon exposure to stressors, assessed longitudinally via frequent monitoring of stressors and mental health. Objective This study aims to investigate the factors predicting mental resilience and adaptive processes and mechanisms contributing to mental resilience and to provide a methodological and evidence-based framework for later intervention studies. Methods In a multicenter setting, across 5 research sites, a sample with a total target size of 250 young male and female adults was assessed longitudinally over 9 months. Participants were included if they reported at least 3 past stressful life events and an elevated level of (internalizing) mental health problems but were not presently affected by any mental disorder other than mild depression. At baseline, sociodemographic, psychological, neuropsychological, structural, and functional brain imaging; salivary cortisol and α-amylase levels; and cardiovascular data were acquired. In a 6-month longitudinal phase 1, stressor exposure, mental health problems, and perceived positive appraisal were monitored biweekly in a web-based environment, while ecological momentary assessments and ecological physiological assessments took place once per month for 1 week, using mobile phones and wristbands. In a subsequent 3-month longitudinal phase 2, web-based monitoring was reduced to once a month, and psychological resilience and risk factors were assessed again at the end of the 9-month period. In addition, samples for genetic, epigenetic, and microbiome analyses were collected at baseline and at months 3 and 6. As an approximation of resilience, an individual stressor reactivity score will be calculated. Using regularized regression methods, network modeling, ordinary differential equations, landmarking methods, and neural net–based methods for imputation and dimension reduction, we will identify the predictors and mechanisms of stressor reactivity and thus be able to identify resilience factors and mechanisms that facilitate adaptation to stressors. Results Participant inclusion began in October 2020, and data acquisition was completed in June 2022. A total of 249 participants were assessed at baseline, 209 finished longitudinal phase 1, and 153 finished longitudinal phase 2. Conclusions The Dynamic Modelling of Resilience–Observational Study provides a methodological framework and data set to identify predictors and mechanisms of mental resilience, which are intended to serve as an empirical foundation for future intervention studies. International Registered Report Identifier (IRRID) DERR1-10.2196/3981

    Ból i cierpienie. Materiały konferencyjne

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    Ze wstępu: "Coroczne spotkania lekarzy w klasztorze Sióstr Duehaczek, czyli poprawnie Sióstr Kanoniczck Ducha Świętego przy kościele Św. Tomasza w Krakowie przy ulicy Szpitalnej, w tradycyjnym dla tego zakonu terminie - tj. w drugą niedzielę po święcie Trzech Króli - przekształciły się w 1994 roku w sympozja naukowe, poświęcone stałemu tematowi: „Ból i cierpienie”. W tym roku spotkaliśmy się w dniach 17 i 18 stycznia 2004, tradycyjnie już, w Domu Towarzystwa Lekarskiego Krakowskiego przy ulicy Radziwiłłowskiej 4. W skład Komitetu Organizacyjnego Konferencji, wzorem lat ubiegłych weszli: prof, dr hab. med. Andrzej Środka, Kierownik Katedry Historii Medycyny CM UJ, prof, dr hab. med. Janusz Andres, Kierownik Katedry Anestezjologii i Intensywnej Terapii CM UJ, dr hab. med. Zdzisław Gajda, prof. UJ, Przewodniczący Stowarzyszenia Absolwentów Wydziałów Medycznych UJ, dr med. Alicja Macheta, Przewodnicząca Podkarpackiego Oddziału Towarzystwa Anestezjologii i Intensywnej Terapii, dr Maria Dorota Schmidt-Pospuła, Przewodnicząca Krakowskiego Towarzystwa Miłośników Historii Medycyny."(...

    Psycho-social factors associated with mental resilience in the Corona lockdown.

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    The SARS-CoV-2 pandemic is not only a threat to physical health but is also having severe impacts on mental health. Although increases in stress-related symptomatology and other adverse psycho-social outcomes, as well as their most important risk factors have been described, hardly anything is known about potential protective factors. Resilience refers to the maintenance of mental health despite adversity. To gain mechanistic insights about the relationship between described psycho-social resilience factors and resilience specifically in the current crisis, we assessed resilience factors, exposure to Corona crisis-specific and general stressors, as well as internalizing symptoms in a cross-sectional online survey conducted in 24 languages during the most intense phase of the lockdown in Europe (22 March to 19 April) in a convenience sample of N = 15,970 adults. Resilience, as an outcome, was conceptualized as good mental health despite stressor exposure and measured as the inverse residual between actual and predicted symptom total score. Preregistered hypotheses (osf.io/r6btn) were tested with multiple regression models and mediation analyses. Results confirmed our primary hypothesis that positive appraisal style (PAS) is positively associated with resilience (p < 0.0001). The resilience factor PAS also partly mediated the positive association between perceived social support and resilience, and its association with resilience was in turn partly mediated by the ability to easily recover from stress (both p < 0.0001). In comparison with other resilience factors, good stress response recovery and positive appraisal specifically of the consequences of the Corona crisis were the strongest factors. Preregistered exploratory subgroup analyses (osf.io/thka9) showed that all tested resilience factors generalize across major socio-demographic categories. This research identifies modifiable protective factors that can be targeted by public mental health efforts in this and in future pandemics
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