458 research outputs found

    Polynomial ergodicity and asymptotic behaviour of unbounded solutions of abstract evolution equations

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    In this paper we develop the notion of ergodicity to include functions dominated by a weight ww. Such functions have polynomial means and include, amongst many others, the ww-almost periodic functions. This enables us to describe the asymptotic behaviour of unbounded solutions of linear evolution, recurrence and convolution equations. To unify the treatment and allow for further applications, we consider solutions ϕ:GX\phi : G\rightarrow X of generalized evolution equations of the form ()(Bϕ)(t)=Aϕ(t)+ψ(t) (*) (B\phi)(t)=A\phi (t)+\psi (t) for tGt\in G where GG\ is a locally compact abelian group with a closed subsemigroup JJ, AA is a closed linear operator on a Banach space XX, ψ:GX\psi :G\rightarrow X is continuous and BB is a linear operator with characteristic function θB:G^C\theta_{B}:\hat{G}\rightarrow \mathbf{C}. We introduce the resonance set θB1(σ(A))\theta_{B}^{-1}(\sigma (A)) which contains the Beurling spectra of all solutions of the homogeneous equation Bϕ=AϕB\phi =A\circ \phi. For certain classes {\F} of functions from JJ to % X, the spectrum sp_{{\F}}(\phi) of ϕ\phi relative to % {\F} is used to determine membership of {\F}. Our main result gives general conditions under which sp_{{\F}}(\phi)\ is a subset of the resonance set. As a simple consequence we obtain conditions under which \psi |_{J}\in \F implies \phi |_{J}\in {\F}. An important tool is our generalization to unbounded functions of a theorem of Loomis. As applications we obtain generalizations or new proofs of many known results, including theorems of Gelfand, Hille, Katznelson-Tzafriri, Esterle et al., Ph\'{o}ng, Ruess and Arendt-Batty.Comment: 42 page

    Apgar score or birthweight in Chihuahua dogs born by elective Caesarean section : which is the best predictor of the survival at 24 h after birth?

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    In the dog, the correct management of parturition and the prompt neonatal evaluation and assistance can reduce the perinatal mortality rates that are particularly high in toy breeds. Newborn evaluation and factors addressing prognosis are pivotal to guarantee the correct neonatal assistance. Assessment of the Apgar score with viability classification and birthweight are recognized as predictors for neonatal survival in dogs, but breed-specific data are needed for a more feasible application in the dog species, in which wide differences among breeds are known. The present study aimed therefore to: (a) assess the role of Apgar score and birthweight as predictors for the survival of Chihuahua newborn puppies in the first 24 h of life; (b) to assess a cut-off of the Apgar score and birthweight values that can predict the survival of Chihuahua newborn puppies in the first 24 h after birth; (c) to assess the possible effect played by maternal parity, newborn gender and litter-size on Apgar score in Chihuahua newborn puppies, in order to provide breed-specific data for a better neonatal assistance..Data obtained from 176 normal developed Chihuahua puppies born by elective Caesarean section, showed that 62%, 28% and 10% of puppies were classified in the Apgar score classes 7\u201310, 4\u20136 and 0\u20133, respectively, with survival at 24 h after birth of 97%, 96%, 39%, in the three Apgar classes of viability, respectively. Apgar score was a better predictor for survival at 24 h after birth than birthweight (AUC 0.93, P < 0.0001; AUC 0.69, P < 0.01, respectively). Litter-size of 7 puppies/litter plays a negative effect on Apgar score. Apgar score is a better predictor of survival at 24 h than birthweight, and the best cut-off of Apgar score for survival at 24 h after birth is 4, with 96% sensitivity and 77% specificity. The different proportion of \u201cnormal viable\u201d and \u201cless viable\u201d neonates in comparison to other studies highlights that Chihuahua puppies born by elective Caesarean section should be carefully evaluated at birth to provide correct assistance

    An Active-Inference Approach to Second-Person Neuroscience

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    Social neuroscience has often been criticized for approaching the investigation of the neural processes that enable social interaction and cognition from a passive, detached, third-person perspective, without involving any real-time social interaction. With the emergence of second-person neuroscience, investigators have uncovered the unique complexity of neural-activation patterns in actual, real-time interaction. Social cognition that occurs during social interaction is fundamentally different from that unfolding during social observation. However, it remains unclear how the neural correlates of social interaction are to be interpreted. Here, we leverage the active-inference framework to shed light on the mechanisms at play during social interaction in second-person neuroscience studies. Specifically, we show how counterfactually rich mutual predictions, real-time bodily adaptation, and policy selection explain activation in components of the default mode, salience, and frontoparietal networks of the brain, as well as in the basal ganglia. We further argue that these processes constitute the crucial neural processes that underwrite bona fide social interaction. By placing the experimental approach of second-person neuroscience on the theoretical foundation of the active-inference framework, we inform the field of social neuroscience about the mechanisms of real-life interactions. We thereby contribute to the theoretical foundations of empirical second-person neuroscience

    Decaying shock studies of phase transitions in MgOSiO2 systems: implications for the Super-Earths interiors

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    We report an experimental study of the phase diagrams of periclase (MgO), enstatite (MgSiO3) and forsterite (Mg2SiO4) at high pressures. We investigated with laser driven decaying shocks the pressure/temperature curves of MgO, MgSiO3 and Mg2SiO4 between 0.2-1.2 TPa, 0.12-0.5 TPa and 0.2-0.85 TPa respectively. A melting signature has been observed in MgO at 0.47 TPa and 9860 K, while no phase changes were observed neither in MgSiO3 nor in Mg2SiO4. An increasing of reflectivity of MgO, MgSiO3 and Mg2SiO4 liquids have been detected at 0.55 TPa -12 760 K, 0.15 TPa - 7540 K, 0.2 TPa - 5800 K, respectively. In contrast to SiO2, melting and metallization of these compounds do not coincide implying the presence of poor electrically conducting liquids close to the melting lines. This has important implications for the generation of dynamos in Super-earths mantles

    Clinical implications, safety, efficacy of Recombinant Human Granulocyte Colony-Stimulating Factors and Pegylated Equivalent

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    A wide use of recombinant human granulocyte colony-stimulating factors (G-CSFs) and their pegylated equivalent is a significant step forward in the treatment of both solid tumors and hematological malignancies. Evidence-based use of these molecules resulted in more intensive treatments, safely extended to frail and elderly patients, and development of response- and comorbidity-tailored approaches. The available G-CSFs are filgrastim, and the long-acting PegFilgrastim, which are produced in E. Coli cells, and are chemically different from native human G-CSF, and lenograstim, a molecule produced in mammalian cells, with a chemical structure identical to native human G-CSF. These chemical differences produce a diverse interaction with receptors and stimulated neutrophils. For instance, lenograstim binds to receptors in the same way of endogenous ligand, and neutrophils obtained from stimulation with this G-CSF have a physiological activity profile similar to neutrophils normally generated in humans. Conversely, the different interaction between filgrastim and G-CSF receptor is more frequently associated with morphological abnormalities, reduced motility and chemotaxis and a reduced response to bacterial stimuli in induced neutrophils. On this background, we reviewed available evidence in order to analyze the impact of these chemical and pharmacodynamic differences among G-CSF molecules on safety, particularly in healthy peripheral-blood stem-cells donors, functional qualities of inducted neutrophils, and mobilization of hematopoietic stem cells.&nbsp

    Aberrant computational mechanisms of social learning and decision-making in schizophrenia and borderline personality disorder

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    Psychiatric disorders are ubiquitously characterized by debilitating social impairments. These difficulties are thought to emerge from aberrant social inference. In order to elucidate the underlying computational mechanisms, patients diagnosed with major depressive disorder (N = 29), schizophrenia (N = 31), and borderline personality disorder (N = 31) as well as healthy controls (N = 34) performed a probabilistic reward learning task in which participants could learn from social and nonsocial information. Patients with schizophrenia and borderline personality disorder performed more poorly on the task than healthy controls and patients with major depressive disorder. Broken down by domain, borderline personality disorder patients performed better in the social compared to the non-social domain. In contrast, controls and MDD patients showed the opposite pattern and SCZ patients showed no difference between domains. In effect, borderline personality disorder patients gave up a possible overall performance advantage by concentrating their learning in the social at the expense of the non-social domain. We used computational modeling to assess learning and decision-making parameters estimated for each participant from their behavior. This enabled additional insights into the underlying learning and decision-making mechanisms. Patients with borderline personality disorder showed slower learning from social and non-social information and an exaggerated sensitivity to changes in environmental volatility, both in the non-social and the social domain, but more so in the latter. Regarding decision-making the modeling revealed that compared to controls and major depression patients, patients with borderline personality disorder and schizophrenia showed a stronger reliance on social relative to non-social information when making choices. Depressed patients did not differ significantly from controls in this respect. Overall, our results are consistent with the notion of a general interpersonal hypersensitivity in borderline personality disorder and schizophrenia based on a shared computational mechanism characterized by an over-reliance on beliefs about others in making decisions and by an exaggerated need to make sense of others during learning specifically in borderline personality disorder
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