Reciprocating instruments made from M-wire alloy have been proposed to reduce the risk of fracture. No information is available on the surface alteration after single and multiple uses in root canals. Two reciprocating NiTi instruments were used on extracted teeth up to three times. ESEM/EDS analysis was conducted to determine defects, alterations, and wear features of the apical third of instruments and metallographic analysis was performed on the cross-section of new and used instruments to compare alloy properties. Topography of apical portion was evaluated by AFM before and after uses. Extracted single-rooted teeth were divided into two groups and instrumented according to the manufacturer's recommendations with: (A) WaveOne Primary and (B) Reciproc R25. Each group was divided into three subgroups according to the number of canals instrumented: 1, 2, and 3, respectively. Chi square test was performed to verify homogeneity of defects distribution and GLM to evaluate the differences of RMS at baseline and after use for both groups (α level 0.05). No instrument fractured and no spiral distortions were observed under optical microscope even when the number of uses increased. Not significant differences were found for WaveOne and Reciproc. Blades presented a wrapped portion in WaveOne group and a more symmetrical feature in Reciproc group. Metallographic analysis revealed in both groups the presence of twinned martensitic grains with isolated flat austenitic areas. Both instruments demonstrated limited alteration, such as tip deformation and wear. This study confirmed the safe clinical use of both instruments for shaping multi-rooted teeth.

Promoting academic success among undergraduate students is crucial for tackling the need to foster employability competencies. Low levels of academic attainment in higher education, along with the increasing number of persons participating in tertiary education, represent crucial trends, which need to be studied in order to develop efficient retention practices. The current study aimed to investigate the relationship between relevant factors that can foster academic success: learning strategies, future orientation, and academic self-efficacy. To this purpose, a longitudinal study was performed on a sample of N = 87 undergraduate students from one of the largest Italian universities (63.4% males, 74.2% enrolled in the first year). Participants filled in an online questionnaire at two different time points, with a time lag of 12 months. Results of a moderated mediation model indicated that the relationship between learning strategies at Time 1 (T1) and Grade Point Average (GPA) at Time 2 (T2) was mediated by students’ future orientation. Moreover, this association was moderated by T1 academic self-efficacy. These results suggest that learning strategies positively influence GPA through an enhanced future orientation, in particular when students report high or medium levels of self-efficacy. The current findings invite a thorough review of training interventions for improving academic achievement.

The present study aimed to explore the mediating role of hostile customer relations in the association between emotional dissonance and workers’ mental health. Moreover, the moderating role of proactive personality as a buffer against hostile customer relations was assessed. Emotional demands become crucial within professions that involve a direct relationship with clients and, if poorly managed, can negatively affect workers’ health and performance. Accordingly, data were collected on a sample of n = 918 mass-retail employees working for one of the leading Italian supermarket companies. Most participants were women (62.7%) with a mean age = 40.38 (SD = 7.68). The results of a moderated mediation analysis revealed that emotional dissonance was related to more hostile customer relations that, in turn, were associated with higher rates of mental health symptoms. Proactive personality emerged as a protecting factor that prevented the onset of conflicts with clients, particularly among workers experiencing high levels of emotional dissonance. The identification of resources enabling management of emotional demands could suggest suitable adaptive strategies for customer-facing roles, thus preventing the occurrence of adverse mental health symptoms.

Human reliability analysis (HRA) is a major concern for organizations. While various tools, methods, and instruments have been developed by the scientific community to assess human error probability, few of them actually consider human factors impact in their analysis. The active role that workers have in shaping their own performance should be taken into account in order to understand the causal factors that may lead to errors while performing a task and identifying which human factors may prevent errors from occurring. In line with this purpose, the aim of this study is to present a new methodology for the assessment of human reliability. The proposed model relies on well-known HRA methodologies (such as SPAR-H and HEART) and integrates them in a unified framework in which human factors assume the role of safety barriers against human error. A test case of the new method was carried out in a logistics hub of an energy company. Our results indicate that human factors play a significant role in preventing workers from making errors while performing tasks by reducing human error probability. The limits and implications of the study are discussed.

Safety at work should be considered as the result of the daily interaction of operators. The present research wants to analyze which factors are involved in the development of social networks about safety at work. We assumed that two relational non-technical skills, such as safety communication and safety team member support, affect the in-degree and out-degree bonds of workers in social networks. One hundred and eight workers of a warehouse were the participants of the research, in which they were asked to fill out a self-reported questionnaire. Multiple linear regression analysis was used to test the hypotheses. Results confirmed that safety communication and safety support skills play a role in determining the quantity and the quality of social bonds that workers can create at the workplace. To be specific, while safety communication was found to be associated with out-degree centrality (b = 0.24; p = 0.01), a nonsignificant relationship was found for in-degree centrality. In contrast, safety team member support was found to be associated with in-degree centrality (b = 0.28; p = 0.04). In other words, on the one hand, it was found that high levels of safety communication skills are associated with the tendency of workers to proactively search for colleagues with whom they can share information about safety. On the other hand, workers with high levels of safety support skills tend to be considered as reference points in terms of safety by colleagues, who are more prone to look for their help. Implications for both scientists and practitioners are discussed.