A definition of nonstandard universe which gets over the limitation to the finite levels of the cumulative hierarchy is proposed. Though necessarily nonwellfounded, nonstandard universes are arranged in strata in the likeness of superstructures and allow a rank function taking linearly ordered values. Nonstandard universes are also constructed which model the whole ZFC theory without regularity and satisfy the κ-saturation property.

Assuming the existence of an inaccessible cardinal, transitive full models of the whole set theory, equipped with a linearly valued rank function, are constructed. Such models provide a global framework for nonstandard mathematics.

A nonstandard set theory ∗ZFC is proposed that axiomatizes the nonstandard embedding ∗. Besides the usual principles of nonstandard analysis, all axioms of ZFC except regularity are assumed. A strong form of saturation is also postulated. ∗ZFC is a conservative extension of ZFC.

The naïve idea of “size” for collections seems to obey both Aristotle’s Principle: “the whole is greater than its parts” and Cantor’s Principle: “1-to-1 correspondences preserve size”. Notoriously, Aristotle’s and Cantor’s principles are incompatible for infinite collections. Cantor’s theory of cardinalities weakens the former principle to “the part is not greater than the whole”, but the outcoming cardinal arithmetic is very unusual. It does not allow for inverse operations, and so there is no direct way of introducing infinitesimal numbers. Here (...) we maintain Aristotle’s principle, instead halving Cantor’s principle to “equinumerous collections are in 1–1 correspondence”. In this way we obtain a very nice arithmetic: in fact, our “numerosities” may be taken to be nonstandard integers. These numerosities appear naturally suited to sets of ordinals, but they depend, for generic sets, on a “labelling” of the universe by ordinals. The problem of finding a canonical way of attaching numerosities to all sets seems to be worth further investigation. (shrink)

We introduceself-divisibleultrafilters, which we prove to be precisely those$w$such that the weak congruence relation$\equiv _w$introduced by Šobot is an equivalence relation on$\beta {\mathbb Z}$. We provide several examples and additional characterisations; notably we show that$w$is self-divisible if and only if$\equiv _w$coincides with the strong congruence relation$\mathrel {\equiv ^{\mathrm {s}}_{w}}$, if and only if the quotient$(\beta {\mathbb Z},\oplus )/\mathord {\mathrel {\equiv ^{\mathrm {s}}_{w}}}$is a profinite group. We also construct an ultrafilter$w$such that$\equiv _w$fails to be symmetric, and describe the interaction between the (...) aforementioned quotient and the profinite completion$\hat {{\mathbb Z}}$of the integers. (shrink)

In this paper two new combinatorial principles in nonstandard analysis are isolated and applications are given. The second principle provides an equivalent formulation of Henson's isomorphism property.

We study combinatorial principles related to the isomorphism property and the special model axiom in nonstandard analysis.

A definition of nonstandard universe which gets over the limitation to the finite levels of the cumulative hierarchy is proposed. Though necessarily nonwellfounded, nonstandard universes are arranged in strata in the likeness of superstructures and allow a rank function taking linearly ordered values. Nonstandard universes are also constructed which model the whole ZFC theory without regularity and satisfy the $\kappa$-saturation property.

The paper discusses an ethical analysis of three common cases involving the most popular requests in rhinoplasty. As the nose plays a fundamental role in the aesthetics and physiognomy of the human face, the request for rhinoplasty may be an expression of both subjective discomfort and objective dysfunction. The paper aims, therefore, to fill the gap between qualitative-subjective impressions related to bodily self-perception and its quantitative-objective assessment. Ethical evaluation should start with consideration of the formal object and circumstances of the (...) act, by posing the following question: Is this a real clinical case? Only after an undoubtedly positive answer to this question, should we consider specific case-related aspects; i.e., the best scientific evidence, available nosography and informed consent, before conducting an ethical evaluation of the case. DOI: 10.5294/pebi.2016.20.1.8. (shrink)

Rips et al. claim that the principles underlying the structure of natural numbers cannot be inferred from interactions with the physical world. However, in their target article they failed to consider an important source of interaction: finger counting. Here, we show that finger counting satisfies all the conditions required for allowing the concept of numbers to emerge from sensorimotor experience through a bottom-up process.

One of the difficulties nurses experience in clinical practice in relation to ethical issues in connection with young oncology patients is moral distress. In this descriptive correlational study, the Moral Distress Scale-Paediatric Version (MDS-PV) was translated from the original language and tested on a conventional sample of nurses working in paediatric oncology and haematology wards, in six north paediatric hospitals of Italy. 13.7% of the total respondents claimed that they had changed unit or hospital due to moral distress. The items (...) with the highest mean intensity in the sample were almost all connected with medical and nursing competence and have considerably higher values than frequency. The instrument was found to be reliable. The results confirmed the validity of the MDS-PV (Cronbach’s alpha = 0.959). This study represents the first small-scale attempt to validate MDS-PV for use in paediatric oncology-ematology nurses in Italy. (shrink)

Prosocial behavior is critical for the natural development of an individual as well as for promoting social relationships. Although this complex behavior results from gratuitous acts occurring between an agent and a recipient and a wealth of literature on prosocial behavior has investigated these actions, little is known about the effects on the recipient and the neurobiology underlying them. In this study, we used functional magnetic resonance imaging to identify neural correlates of receiving prosocial behavior in the context of real-world (...) experiences, with different types of action provided by the agent, including practical help and effort appreciation. Practical help was associated with increased activation in a network of regions spanning across bilateral superior temporal sulcus, temporoparietal junction, temporal pole, and medial prefrontal cortex. Effort appreciation was associated with activation and increased task-modulated connectivity of the occipital cortex. Prosocial-dependent brain responses were associated with positive affect. Our results support the role of the theory of mind network and the visual cortices in mediating the positive effects of receiving gratuitous help. Moreover, they indicate that specific types of prosocial behavior are mediated by distinct brain networks, which further demonstrates the uniqueness of the psychological processes underlying prosocial actions. (shrink)

Histone octamers (hos) and DNA topoisomerase I contribute, along with other proteins, to the higher order structure of chromatin. Here we report on the similar topological requirements of these two protein model systems for their interaction with DNA. Both histone octamers and topoisomerase I positively and consistently respond to DNA supercoiling and curvature, and to the spatial accessibility of the preferential interaction sites. These findings (1) point to the relevance of the topology‐related DNA conformation in protein interactions and define the (...) particular role of the helically phased rotational information; and (2) help to solve the apparent paradoxical behaviour of ubiquitous and abundant proteins that interact with defined DNA sites in spite of the lack of clear sequence consensuses. Considering firstly, that the interactions with DNA of both DNA topoisomerase I and histone octamers are topology‐sensitive and that upon their interaction the DNA conformation is modified; and secondly, that similar behaviours have also been reported for DNA topoisomerase II and histone H1, a topology‐based functional correlation among all these determinants of the higher order structure of chromatin is here suggested. (shrink)

With his massive redeployment hypothesis (MRH), Anderson claims that novel cognitive functions are likely to rely on pre-existing circuits already possessing suitable resources. Here, we put forward recent findings from studies in numerical cognition in order to show that the role of sensorimotor experience in the ontogenetical development of a new function has been largely underestimated in Anderson's proposal.

Heath and Tversky (1991, Journal of Risk and Uncertainty 4:5–28) posed that reaction to ambiguity is driven by perceived competence. Competence effects may be inconsistent with ambiguity aversion if betting on own judgement is preferred to betting on a chance event, because judgemental probabilities are more ambiguous than chance events. This laboratory experiment analyses whether ambiguity affects prices and volumes in a double auction market, and contrasts ambiguity aversion to competence effects. In order to test for the presence of competence (...) effects, in the experiment uncertainty is tied to the realisation of events about which the decision maker is more or less knowledgeable. Two experiments are presented: in the first, knowledge is exogenous, whereas in the second the knowledge judgement is endogenous. Market prices provide evidence in favour of the competence hypothesis only when competence is self-assessed. Comparable volumes are observed in both experiments. (shrink)

Background:Personal values influence nursing students’ development of professional values, which affect professional outcomes, and how nursing students react to different situations. Personal values can be shaped by different factors, including culture, gender, and age.Aims:To explore personal values held by nursing students, and to verify if and how gender and year of study affect nursing students’ personal values.Research design:A multicenter, cross-sectional study was used.Participants and research context:The whole population of nursing undergraduate students available at the time was recruited from eight centers (...) of two Universities, composing a sample of 947 students. Demographic data were collected and it was administered the Portrait Values Questionnaire.Ethical considerations:Ethical approval was obtained from the Institutional Review Boards of the University of the participating centers.Findings:The study sample was mainly composed of young (92.6%, n = 877), female (77.3%, n = 732), Italian (95.8%, n = 907), and unmarried (98.6%, n = 934) nursing students. The most important value for nursing students, consistently through the years of nursing school, was Self-transcendence, which has the motivational emphasis on helping others and selflessness. Then, we found that male students had higher levels of Power (p < 0.001) and Achievement (p = 0.031), while female students outscored male students in Benevolence (p = 0.005) and Security (p = 0.006). Year of study showed no statistically significant difference.Discussion:Nursing students express high levels in hetero-directed values. Male nursing students, although they choose a stereotypically feminine profession, outscored females in stereotypical masculine values such as dominance and success. This is the first study that describes the personal value profile of undergraduate nursing students, according to the Theory of Basic Human Values, and it is a starting point for future research.Conclusion:Nursing educators might want to consider the findings from this study while guiding students in developing awareness for their personal values. (shrink)

399 a.C.: la città di Atene condanna a morte uno dei suoi figli più autorevoli, Socrate. Cosa è successo davvero nei mesi in cui si è svolta la vicenda giudiziaria? Si ripete spesso che si trattò di un processo politico mascherato, per colpire le simpatie oligarchiche dell'anziano filosofo. Ma forse il vero oggetto del contendere in questa vicenda fu proprio il pensiero di Socrate. Fino a che punto una comunità--ieri come oggi--può tollerare che i principi e i valori su cui (...) si fonda siano messi radicalmente in discussione? E davvero le ragioni della filosofia e quelle della città non sono compatibili? Una lettura originale di uno dei più celebri processi della storia. (shrink)

I temi della corporeità, della sporcizia, della materialità, in una ricerca esasperata di realismo.