Special issue on materials development by additive manufacturing techniques

Additive manufacturing (AM) processes are steadily gaining attention from many industrial fields, as they are revolutionizing components' designs and production lines. However, the full application of these technologies to industrial manufacturing has to be supported by the study of the AM materials' properties and their correlations with the feedstock and the building conditions. Furthermore, nowadays, only a limited number of materials processable by AM are available on the market. It is, therefore, fundamental to widen the materials' portfolio and to study and develop new materials that can take advantage of these unique building processes. The present special issue collects recent research activities on these topics

The Italian version of the Wong-Law Emotional Intelligence Scale (WLEIS-I): a second-order factor analysis

The Wong and Law Emotional Intelligence Scale (WLEIS) is a 16-item self-report measure of emotional intelligence, based on the revised model by Mayer and Salovey. The scale measures four dimensions: Self-Emotional Appraisal, Others' Emotion Appraisal, Use Of Emotion, Regulation Of Emotions, loading onto a higher-order emotional intelligence factor. The WLEIS has been translated and validated in several cultural contexts, but to date there is no Italian translation, and no studies investigated its factor structure in the Italian community. This study aimed at translating the WLEIS in Italian, analysing its psychometric properties in Italian adults from the community, and testing the fit between the data and the original model by Wong and Law. We also tested correlations between WLEIS and measures of the Big Five personality factors and attachment. We found that the scale was internally consistent, and the second-order factor solution fit the data well. We also found significant positive correlations with agreeableness, extraversion, and perception of the self and the others, and negative correlation with neuroticism. These results represent a preliminary attempt to study the application of the WLEIS in Italian community settings, with implications for assessment and intervention to enhance the subjective and psychological well-being of individuals

Specific mindfulness traits protect against negative effects of trait anxiety on medical student wellbeing during high-pressure periods

Medical education is highly demanding and evidence shows that medical students are three times more susceptible to deteriorating physical and mental health than the average college student. While trait anxiety may further increase such risk, little is known about the role of trait mindfulness in mitigating these effects. Here we examine the protective role of specific mindfulness facets as mediators in pathways from trait anxiety to perceived stress, psychosomatic burden and sleep-wake quality in medical students, across repeated measurements throughout the first trimester of the school year. Preclinical medical students enrolled in the second year of the Medical School of University of Bologna completed self-report questionnaires examining personality traits as well as physical and psychological wellbeing. Data were collected at the beginning (Time 1: N = 349) and the end of the first trimester (Time 2: N = 305). As students approached the end of the trimester and upcoming exams, reported levels of perceived stress, psychosomatic problems and difficulties in wakefulness increased significantly compared to the beginning of the trimester. Mediation results showed that trait anxiety predicted such outcomes whereas the protective role of mindfulness facets in mitigating these effects was significant only at Time 2. Specific facets of Nonjudging of inner experience and Acting with awareness proved to be the most effective mediators. Findings highlight that the beneficial role of mindfulness facets in mitigating negative consequences of trait anxiety on medical student wellbeing is revealed in high-pressure periods and when self-regulation is needed the most. Cultivating awareness and nonjudgmental acceptance of one’s inner experiences is a crucial self-regulation resource that can help medical students sustain their wellbeing as they learn and throughout their high-pressure education and professional careers

The K\ue4hler quotient resolution of C3/\u393 singularities, the McKay correspondence and D=3 N = 2 Chern-Simons gauge theories

We advocate that the generalized Kronheimer construction of the Ka \u308hler quotient crepant resolution M\u3b6 12\u2192 C3/\u393 of an orbifold singularity where \u393 82 SU(3) is a finite subgroup naturally defines the field content and the interaction structure of a superconformal Chern-Simons Gauge Theory. This latter is suppos- edlythedualofanM2-branesolutionofD=11supergravitywithC 7M\u3b6 astransversespace.Weillustrate and discuss many aspects of this type of constructions emphasizing that the equation p 27 p = 0 which provides the Ka \u308hler analogue of the holomorphic sector in the hyperKa \u308hler moment map equations canonically defines the structure of a universal superpotential in the CS theory. Furthermore the kernel D\u393 of the above equation can be described as the orbit with respect to a quiver Lie group G\u393 of a special locus L\u393 82 Hom\u393 (Q 97 R, R) that has also a universal definition. We provide an extensive discussion of the relation between the coset manifold G\u393/F\u393, the gauge group F\u393 being the maximal compact subgroup of the quiver group, the moment map equations and the first Chern classes of the so named tautological vector bundles that are in one-to-one correspondence with the nontrivial irreps of \u393. These first Chern classes are represented by (1,1)-forms on M\u3b6 and provide a basis for the cohomology group H2(M\u3b6 ). We also discuss the relation with conjugacy classes of \u393 and we provide the explicit construction of several examples emphasizing the role of a general- ized McKay correspondence. The case of the ALE manifold resolution of C2/\u393 singularities is utilized as a comparison term and new formulae related with the complex presentation of Gibbons-Hawking metrics are exhibited

Individual differences in interpersonal security predict suicidal ideation and problem gambling

Suicidality and problem gambling represent global health issues. Based on evidence from recent literature, the aim of the present study was to test a theoretical model, in which: (1) Emotional Intelligence and Self and Other Representations of adult attachment combine into a latent factor representing Interpersonal Security; (2) Interpersonal Security negatively predicts Problem Gambling and Suicidal Ideation, respectively; (3) Problem Gambling positively predicts Suicidal Ideation. We used Structural Equation Modelling to test the study hypotheses. The model showed good fit to the data. Factor loadings were high and statistically significant. We found that the hypothesis of Emotional Intelligence and Self and Other Representations combining into a common factor, Interpersonal Security, is empirically supported. The joint effect of Interpersonal Security and Problem Gambling explains about the 63% of variance of Suicidal ideation. The path from Interpersonal Security to Suicidal Ideation is significant and high, whilst the path from Problem Gambling to Suicidal Ideation is not significant. Interpersonal Security explains about 16% of the variance of Problem Gambling. These results outline an integrated model of Suicidal Ideation and Problem Gambling in the community from an interpersonal-psychological perspective, with important implications for researchers, mental health practitioners, and policymakers

Strengthening strategies for an Al alloy processed by in-situ alloying during laser powder bed fusion

In this work, a high strength Al alloy was successfully processed via in-situ alloying of AlSi10Mg and Cu elemental powders during Laser Powder Bed Fusion. To get superior strength, 4 wt% of Cu was added to AlSi10Mg composition to benefit from the additional solid solution and precipitation strengthening mechanisms induced by Cu atoms. Microstructure, chemical composition, hardness, and tensile properties of as-built samples were firstly determined. The microstructure showed a dual eutectic formed by Si precipitates intermixed with -Al2Cu phase. The average Cu concentration was 3.96 ± 0.26 wt% in line with the theoretical one. Hardness and yield strength of AlSi10Mg + 4Cu alloy showed an increase of respectively 8.8 % and 35.6 % compared to the as-built AlSi10Mg, owing to the highly super-saturated solid solution of Si and Cu atoms upon rapid solidification. After that, a direct aging heat-treatment strategy was pursued to fully exploit the potential alloy precipitation by heating as-built samples at temperatures between 160 and 190 °C. A maximum hardness response was achieved after 1 h at 175 °C. The high hardening was primarily attributed to a mix of -Al2Cu and Si phases coupled with a still high solid solution content. Nevertheless, direct aging slightly decreased the alloy ductility due to the prominent precipitation of brittle Si particles during aging and the presence of Cu inhomogeneities formed after in-situ alloying

THERMODYNAMIC APPROACH TO MODELING BIOFUELS PRODUCTION FROM MICROALGAE AND CYANOBACTERIA: THE ROLE OF ELECTROCHEMICAL POTENTIAL

Biofuels from 3rd-generation feed-stocks like microalgae and cyanobacteria are considered possible replacements of fossil fuels and a means to reduce emissions of the greenhouse gas CO2. There is a need to understand how to control microbial growth by manipulating environmental conditions to increase photosynthetic biofuel productivity and/or reduce manufacturing costs. A novel, non-equilibrium, bio-thermodynamic-based model was developed here to fundamentally link electrochemical potential, membrane electric potential, trans-membrane pH gradient, and external temperature with microbial proliferation and bio-system behaviour

Personality and suicidal ideation in the elderly: factorial invariance and latent means structures across age

Objectives: Suicide among the elderly is a dramatic global health problem. Although fatal attempts are frequent in the elderly, research indicated that they rarely present long-term elaboration of suicidal ideation and communicate their intents. Consequently, risk factor detection and assessment are salient. Although evidence on the association between personality and suicidal ideation in young adults is accumulating, little is known about its relevance in the elderly. The purpose of the present study was to analyze the components of a measurement model that are invariant across young adults and older adults and then investigate the relations among dimensions of personality and suicide risk. We postulated a specific relation pattern a priori and tested the hypotheses statistically in order to examine the models for equivalency of the factorial measurement. Method: We investigated 316 young adults and 339 older adults, who were administered self-report questionnaires to assess depression, hopelessness, alternative five-factor model of personality, and self–other perception. Results: Multigroup confirmatory factor analyses were conducted, yielding a final model with excellent fit to the data. This model showed a similar pattern of associations between suicidal ideation and personality across both groups. Conclusions: Although the elderly are exposed to specific life stressors associated with suicidal ideation, our findings suggest that the elderly and young adults may be similar on personality and psychopathology variables predicting suicidal ideation than previously hypothesized. Implications are provided for enhanced assessment and intervention of the elderly high in neuroticism, depression, hopelessness, and with negative self–other perception

Synergic strategies to improve the PBF-LB/M processability of a cracking-sensitive alloy

The Powder Bed Fusion-Laser Beam\Metals (PBF-LB\M) is a promising additive manufacturing process that can be used to directly produce functional components with a complex shape for a wide variety of applications. However, the layer-by-layer scanning and high cooling rates result in a high thermal gra- dient and thus, in thermally induced stresses. The stresses developed during the additive process could lead to undesirable cracking and delamination phenomena that can seriously affect the performance of the final component. The alloy composition can exacerbate crack and delamination formation, however, the need to expand the portfolio of high-strength materials processable for PBF-LB\M makes the resolu- tion of these undesirable phenomena a primary challenge in the additive manufacturing field. This works aims to systematically investigate some strategies to make processable non-standard compositions. As no standard compositions, the promising pre-alloyed AlSi10Cu8Mg composition was chosen for the present work. Based on the results obtained from a condition of severe delamination, the synergetic use of appro- priate process parameters and support structures can lead to crack-free and fully dense specimens also when platform heating is not allowed. The developed approach could also be applied to adapt other cracking-sensitive alloys for PBF-LB\M production

Nuove strategie terapeutiche nel trattamento delle ferite difficili

Introduzione. Il trattamento medico-chirurgico delle ferite difficili rappresenta un problema socio-sanitario in continua crescita, colpendo attualmente nel nostro Paese circa 2.000.000 di persone. La “ferita difficile” non è altro che una perdita di sostanza cutanea, a patogenesi multifattoriale, che non tende alla guarigione in modo spontaneo. Numerosi studi presenti in letteratura hanno evidenziato che l’uso delle medicazioni avanzate consente di raggiungere migliori risultati clinici ed economici nel processo di guarigione delle ferite difficili, assicurando sia una permanenza superiore sulla lesione che accorciando il tempo di trattamento, in quanto viene richiesto un minor numero di applicazioni rispetto alle medicazioni tradizionali. La Wound Bed Preparation (WBP) può essere definita come la gestione globale e coordinata della lesione cutanea atta a rimuovere le barriere locali alla guarigione o a promuovere l’efficacia di misure terapeutiche innovative. La medicazione avanzata non è altro che un materiale di copertura che possiede caratteristiche di biocompatibilità. Scopo della medicazione avanzata è quello di creare l’ambiente ideale per il processo di cicatrizzazione isolando la ferita da eventuali traumi ed infezioni esterne. Pazienti e metodi. Nell’Ambulatorio “Ferite Difficili” della Cattedra di Chirurgia Plastica e Ricostruttiva del Policlinico Umberto I di Roma, dal gennaio al dicembre 2006, sono stati trattati 570 pazienti (308 uomini – 262 donne), con un’età variabile dai 2 giorni agli 85 anni, affetti da ulcere di varia natura. Nell’ambito dei nostri casi clinici sono stati selezionati 200 soggetti divisi casualmente in due gruppi: gruppo A - 100 pazienti trattati unicamente con medicazioni tradizionali; gruppo B - 100 pazienti trattati unicamente con medicazioni avanzate. Ogni paziente è stato trattato localmente con medicazioni periodiche, specifiche a seconda del tipo di ferita difficile presentata. Inoltre si è proceduto all’individuazione ed alla cura dei fattori sistemici, concause dell’ulcera. Il nostro protocollo prevedeva medicazioni due o tre volte alla settimana a seconda che si trattasse di ferite infette o non infette, per un periodo cha poteva variare da un mese per i casi meno gravi ad un anno per le forme croniche. Risultati. È risultata evidente una più alta percentuale di guarigione ottenuta attraverso l’utilizzo delle medicazioni avanzate. Nel Gruppo A si sono ottenuti i seguenti risultati: la guarigione del 53% delle ferite; il restante 47% non è guarito, ma nel 17%, le medicazioni sono state di ausilio alla preparazione del letto vascolare per l’esecuzione di un intervento definitivo (applicazione di innesti o lembi locali); nel rimanente 30%, invece, è stato ottenuto solo un modestissimo miglioramento della lesione che è ancora in fase di trattamento. Nel Gruppo B si è ottenuta la guarigione del 65% delle ferite; nel restante 35% non guarito, nel 15% le medicazioni sono state di ausilio alla preparazione del letto vascolare per l’esecuzione di un intervento definitivo (applicazione di innesti o lembi locali) mentre nel rimanente 20% si è raggiunto comunque un notevole miglioramento della lesione (con riduzione delle dimensioni, scomparsa dell’infezione e miglioramento della qualità di vita del paziente). Discussione e conclusioni. In sintesi, emerge che le medicazioni avanzate, se correttamente impiegate, offrono vantaggi in termini di efficacia clinica (velocità di guarigione della lesione), di qualità della vita del paziente e di economicità. Non ultimo è da considerare che la ferita difficile è spesso l’epifenomeno di una malattia sistemica. La ferita difficile richiede, quindi, un trattamento multidisciplinare. difficile richiede, quindi, un trattamento multidisciplinare. Results. The results showed a higher percentage of recovery reached by using the advanced dressings. Group A showed the followings results: the 53% of patients recovered from wounds; the remaining 47% patients did’nt not recover but in 17% cases medications showed to be of some help in the preparation of the vascular bed for the execution of a definitive operation (application of grafts or local edges), while the remaining 30% has shown a scarce improvement of the injury and they are still under treatment. Group B showed the 65% of patients recovered from wounds; as for the remaining 35% not recovered patients, medications represented an auxiliary aid to the preparation of the vascular bed for the execution of a definitive operation (application of grafts or local edges) for the 15% of patients, while the remaining 20%, even if not completely recovered, showed a notable improvement of the injury (reduction of the dimensions and disappearance of the infection and improvement of the patient quality of life). Conclusions. In synthesis, it emerges that the advanced dressings, if correctly used, offer advantages in terms of clinical effectiveness (rapid recovery from the injury), patient quality of the life and cheapness. It has also to be considered that the difficult wound is often the epiphenomenon of a systemic illness. The difficult wound requires, therefore, a multidisciplinary treatment