Theory of the evolutionary minority game

We present a theory which describes a recently introduced model of an evolving, adaptive system in which agents compete to be in the minority. The agents themselves are able to evolve their strategies over time in an attempt to improve their performance. The present theory explicitly demonstrates the self-interaction, or so-called market impact, that agents in such systems experience

Habitat fragmentation and anthropogenic factors affect wildcat Felis silvestris silvestris occupancy and detectability on Mt Etna

Knowledge of patterns of occupancy is crucial for planning sound biological management and for identifying areas which require paramount conservation attention. The European wildcat Felis silvestris is an elusive carnivore and is classified as ‘least concern’ on the IUCN red list, but with a decreasing population trend in some areas. Sicily hosts a peculiar wildcat population, which deserves conservation and management actions, due to its isolation from the mainland. Patterns of occupancy for wildcats are unknown in Italy, and especially in Sicily. We aimed to identify which ecological drivers determined wildcat occurrence on Mt Etna and to provide conservation actions to promote the wildcats’ long-term survival in this peculiar environment. The genetic identity of the wildcat population was confirmed through a scat-collection which detected 22 different wildcat individuals. We analysed wildcat detections collected by 91 cameras using an occupancy frame work to assess which covariates influenced the detection (p) and the occupancy (ψ) estimates. We recorded 70 detections of the target species from 38 cameras within 3377 trap-days. Wildcat detection was positively influenced by the distance to the major paved roads and negatively affected by the presence of humans. Wildcat occupancy was positively associated with mixed forest and negatively influenced by pine forest, fragmentation of mixed forest and altitude. A spatially explicit predicted occupancy map, validated using an independent dataset of wildcat presence records, showed that higher occupancy estimates were scattered, mainly located on the north face and at lower altitude. Habitat fragmentation has been claimed as a significant threat for the wildcat and this is the first study that has ascertained this as a limiting factor for wildcat occurrence. Conservation actions should promote interconnectivity between areas with high predicted wildcat occupancy while minimising the loss of habitat

Theory of enhanced performance emerging in a sparsely-connected competitive population

We provide an analytic theory to explain Anghel et al.'s recent numerical finding whereby a maximum in the global performance emerges for a sparsely-connected competitive population [Phys. Rev. Lett. 92, 058701 (2004)]. We show that the effect originates in the highly-correlated dynamics of strategy choice, and can be significantly enhanced using a simple modification to the model.Comment: This revised version will appear in PRE as a Rapid Com

Morphological variation of the newly confirmed population of the javelin sand boa, Eryx jaculus (Linnaeus, 1758) (Serpentes, erycidae) in Sicily, Italy

The presence of the Javelin sand boa in Sicily has recently been confirmed. Here the morphological characters and sexual dimorphism of the Sicilian population of Eryx jaculus are presented. Seven meristic and six metric characters in 96 specimens from Sicily were examined. The results show that tail length, snout-vent length, the distance between nostrils and the number of ventral and subcaudal scales are different between sexes. The characters found in the Sicilian population of the Javelin sand boa resemble those of the African population (ssp. jaculus) rather than the Eurasian population (ssp. turcicus), but biomolecular studies are necessary to understand its taxonomic identity

Ruptures and repairs of group therapy alliance. an untold story in psychotherapy research

Although previous studies investigated the characteristics of therapeutic alliance in group treatments, there is still a dearth of research on group alliance ruptures and repairs. The model by Safran and Muran was originally developed to address therapeutic alliance in individual therapies, and the usefulness of this approach to group intervention needs to be demonstrated. Alliance ruptures are possible at member to therapist, member to member, member to group levels. Moreover, repairs of ruptures in group are quite complex, i.e., because other group members have to process the rupture even if not directly involved. The aim of the current study is to review the empirical research on group alliance, and to examine whether the rupture repair model can be a suitable framework for clinical understanding and research of the complexity of therapeutic alliance in group treatments. We provide clinical vignettes and commentary to illustrate theoretical and research aspects of therapeutic alliance rupture and repair in groups. Our colleague Jeremy Safran made a substantial contribution to research on therapeutic alliance, and the current paper illustrates the enduring legacy of this work and its potential application to the group therapy context

Cryptic invasion in Southern Europe: The case of Ferrissia fragilis (Pulmonata: Ancylidae) Mediterranean populations

Four populations of the North American ancylid gastropod Ferrissia fragilis have been found in Southern Italy, thus expanding the known Eurasian distribution range of this invasive gastropod to the Mediterranean area. Both mitochondrial markers used for the molecular identification of the sampled specimens (16S and COI) showed a modest to absent haplotypic diversity in the studied Ferrissia populations from Europe and Asia, and their perfect identity with some of the haplotypes observed in North American F. fragilis populations. In the light of the scarce molecular diversity observed in the whole Palaearctic area and of the growing evidences for the ongoing spreading of the species in Europe, the occurrence of a single invasion event from North America possibly linked with aquarium plant trade followed by a rapid spreading of the species in Eurasia is suggested. The record of F. fragilis in Southern Italy caused some doubts on the presence of autochthonous Ferrissia populations in Europe and on the actual existence of Ferrissia wautieri. A molecular analysis of Ferrissia specimens from the loci typici of F. wautieri (Northern Italy) and F. clessiniana (Egypt) is definitely opportune

Revision of the Student Adaptation to College Questionnaire (SACQ) for Use with Italian Students

Background: This multistudy report was aimed at examining the psychometric properties in the Italian context of the Student Adaptation College Questionnaire (SACQ) that represents the most important self-report measure for assessing how students adjust to university. Methods: Three studies were conducted in order to revise and improve the instrument for being more efficient in measuring adjustment to university. Results: The final result was the SACQ-SF consisting in 12 item assessing three dimensions: a) student’s perception of one’s study skills (Studying); b) student’s sense of satisfaction with courses and programs (Satisfaction with curriculum); c) student’s evaluation of the degree to which he has social skills and is making new friends (Social adjustment). Conclusions: Convergent and construct validity may be considered also adequate. In sum, the SACQSF can be considered a promising valuable and efficient instrument in measuring adjustment to university in the Italian context, and probably in the European one too. Further, as a brief instrument, it can be easily administered and used as a quick screening tool

Creep-Fatigue Crack Growth in Power Plant Components

In components operating at high temperature, the presence of defect, that may derive from manufacturing process or operating under critical conditions, could raise to creep-fatigue crack growth even at low loading conditions. Creep- fatigue experimental tests have been performed on P91 material, at 600 °C according to ASTM E2760-10 standard, with focus on the effects of the initial nominal stress intensity factor range, ranging between 16 and 22 MPa m 0.5, and the hold time, ranging between 0.1 and 10 hours. The results will be presented in the paper, together with their application for residual life prediction of a power plant cracked pipe, as case study