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Atomistic simulations are performed to assess how the main characteristics of a pairwise interatomic potential function can affect the occurrence of wear. A Morse-like potential is tailored in its attractive part such as to vary independently the cut-off radius and the maximum value of the attractive (adhesive) force. An ideal numerical experiment is then performed where the interaction between a metal crystal and a probe changes, while their material properties are not affected, to isolate the behavior of the interface. Force functions with larger adhesive force can loosely be interpreted as describing dry contacts while those with smaller adhesive force can be interpreted as describing lubricated contacts. Results demonstrate that the occurrence of wear is strongly dependent on the shape of the interatomic force field, and more specifically on the combination of maximum adhesive force and effective length of the interatomic attraction. Wear can initiate also at small adhesive energy, provided that the maximum adhesive force between atoms is large. When the surface of the crystal is taken to be rough instead of flat, the effect of the interatomic potential function on friction and wear becomes smaller, as the atoms belonging to the roughness are weakly bound to the rest of the crystal and are easily dislodged with any of the force functions we used., Competing Interests: Competing InterestsThe authors have not disclosed any competing interests., (© The Author(s) 2024.)

Teachers and educators are experiencing turmoil under the drastic changes in educational practices caused by the COVID-19 pandemic. According to research, transformational leaders effectively facilitate organizational change by fostering teachers' sense of belonging and boosting social identity in their team members, which can result in better team well-being via higher team cohesion. Recently, research has increasingly explored the role of emotional contagion and its relationship with leadership. Accordingly, the current study aims to delve deeper into the role of emotional contagion in linking transformational leadership to cohesion among teachers in the school setting. To this purpose, 581 teachers from northern Italy filled out a self-report questionnaire (72.1% female, M age = 47.06, and SD age = 11.42). A moderated mediation model was tested to assess the mediating role of organizational identification in the relationship between transformational leadership and team cohesion and how emotional contagion may moderate this association. The obtained results provided support to the hypothesized model. Overall, the present study corroborates the critical role of school principals' behavior in fostering greater organizational identification among teachers, which is associated with better team cohesion. This study constitutes an early attempt to gain more insight into the role of emotional variables in explaining the influence of leadership behavior.

Objectives.: Motivation for the study. The impact of the COVID-19 pandemic on the risk of death in cancer patients on chemotherapy and immunotherapy is controversial. Published studies mainly compared patients on anti-cancer therapy to those off treatment or COVID-19 positive cancer patients to COVID-19 negative ones. Few studies were conducted in developing countries. Main findings. Mortality didn't increase in unvaccinated outpatients on active intravenous oncology treatment during the COVID-19 pandemic. Implications. This is the first propensity score-matched cohort study evaluating the impact of the COVID-19 pandemic on the population of unvaccinated oncology patients receiving intravenous anticancer therapy. . To compare all-cause mortality of unvaccinated oncology patients who received chemotherapy or immunotherapy during the pandemic with those treated before the pandemic., Materials and Methods.: We conducted a cohort study in four tertiary hospitals in Argentina. Outpatients with a solid neoplasm of any stage under-going cytotoxic or intravenous immunotherapy were eligible. The pandemic cohort was enrolled during the initial phase of the outbreak and compared with a pre-pandemic cohort using propensity score matching (PSM). Subjects were matched for age, sex, health insurance, risk factors for severe COVID-19 complications, performance status, cancer type and treatment, line of treatment, and body mass index. All-cause mortality was estimated for both cohorts after 6 months of follow-up., Results.: A total of 169 patients were recruited between April and August 2020 for the pandemic cohort and 377 for the pre-pandemic cohort in the same months of 2019; 168 patients were matched. After PSM, all-cause mortality was 17.9% in the pandemic cohort and 18.5% in the pre-pandemic cohort; the Relative Risk was 0.97 (95 % confidence interval: 0.61-1.52; p=0.888). In the pandemic cohort, 30/168 patients died, but none from COVID-19., Conclusions.: Our findings show that the mortality rate of unvaccinated ambulatory patients on active intravenous oncology treatment during the COVID-19 pandemic did not increase.

Starting from the insights of social identity theory and social exchange theory, the present study aimed to understand how social support and organizational identification relate to work engagement. Moreover, it sought to verify if social support and organizational identification interact with each other to explain work engagement three months later. A longitudinal study was conducted on a sample of 150 employees, in which organizational identification, social support, and work engagement were measured through a questionnaire. The results show that when employees can count on their supervisors' and colleagues' support, they will be more engaged in their work. In addition, when an employee strongly identifies with their organization, the employee's evaluation of the social support received from colleagues and supervisors becomes less critical in determining their work engagement. These results confirm our hypotheses and extend the findings of previous research on withdrawal behaviors. From a practical point of view, it seems important for organizations to invest in increasing identification, as well as in building a high-quality social exchange relationship, especially when levels of organizational identification are low or decreasing.

Inspired by the Conservation of Resource theory (Hobfoll, 1989), this study investigated the role of a broad set of personal vulnerabilities, social, and work-related stressors and resources as predictors of workers' well-being during the COVID-19 outbreak. Participants were 594 workers in Italy. Results showed that personality predispostions, such as positivity, neuroticism and conscientiousness as well as key aspects of the individuals' relationship with their work (such as job insecurity, type of employment contract or trust in the organization) emerged as factors promoting (or hampering) workers' adjustment during the COVID -19 outbreak. Interactions between stressors and resources were also found and discussed., Supplementary Information: The online version contains supplementary material available at 10.1007/s12144-021-02408-w., Competing Interests: Conflict of InterestAll authors declare that they have no conflict of interest., (© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2021.)

The purpose of this study was to investigate which social groups are perceived as a threat target and which are perceived as a threat source during the COVID-19 outbreak. In a German sample ( N = 1454) we examined perceptions of social groups ranging from those that are psychologically close and smaller (family, friends, neighbors) to those that are more distal and larger (people living in Germany, humankind). We hypothesized that psychologically closer groups would be perceived as less affected by COVID-19 as well as less threatening than more psychologically distal groups. Based on social identity theorizing, we also hypothesized that stronger identification with humankind would change these patterns. Furthermore, we explored how these threat perceptions relate to adherence to COVID-19 health guidelines. In line with our hypotheses, latent random-slope modelling revealed that psychologically distal and larger groups were perceived as more affected by COVID-19 and as more threatening than psychologically closer and smaller groups. Including identification with humankind as a predictor into the threat target model resulted in a steeper increase in threat target perception patterns, whereas identification with humankind did not predict differences in threat source perceptions. Additionally, an increase in threat source perceptions across social groups was associated with more adherence to health guidelines, whereas an increase in threat target perceptions was not. We fully replicated these findings in a subgroup from the original sample ( N = 989) four weeks later. We argue that societal recovery from this and other crises will be supported by an inclusive approach informed by a sense of our common identity as human beings., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2022 The Author(s).)

The COVID-19 pandemic has triggered health-related anxiety in ways that undermine peoples' mental and physical health. Contextual factors such as living in a high-risk area might further increase the risk of health deterioration. Based on the Social Identity Approach, we argue that social identities can not only be local that are characterized by social interactions, but also be global that are characterized by a symbolic sense of togetherness and that both of these can be a basis for health. In line with these ideas, we tested how identification with one's family and with humankind relates to stress and physical symptoms while experiencing health-related anxiety and being exposed to contextual risk factors. We tested our assumptions in a representative sample (N = 974) two-wave survey study with a 4-week time lag. The results show that anxiety at Time 1 was positively related to stress and physical symptoms at Time 2. Feeling exposed to risk factors related to lower physical health, but was unrelated to stress. Family identification and identification with humankind were both negatively associated with subsequent stress and family identification was negatively associated with subsequent physical symptoms. These findings suggest that for social identities to be beneficial for mental health, they can be embodied as well as symbolic., (© 2021 The Authors. British Journal of Social Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.)

Do leaders who build a sense of shared social identity in their teams thereby protect them from the adverse effects of workplace stress? This is a question that the present paper explores by testing the hypothesis that identity leadership contributes to stronger team identification among employees and, through this, is associated with reduced burnout. We tested this model with unique datasets from the Global Identity Leadership Development (GILD) project with participants from all inhabited continents. We compared two datasets from 2016/2017 ( n = 5290; 20 countries) and 2020/2021 ( n = 7294; 28 countries) and found very similar levels of identity leadership, team identification and burnout across the five years. An inspection of the 2020/2021 data at the onset of and later in the COVID-19 pandemic showed stable identity leadership levels and slightly higher levels of both burnout and team identification. Supporting our hypotheses, we found almost identical indirect effects (2016/2017, b = -0.132; 2020/2021, b = -0.133) across the five-year span in both datasets. Using a subset of n = 111 German participants surveyed over two waves, we found the indirect effect confirmed over time with identity leadership (at T1) predicting team identification and, in turn, burnout, three months later. Finally, we explored whether there could be a "too-much-of-a-good-thing" effect for identity leadership. Speaking against this, we found a u-shaped quadratic effect whereby ratings of identity leadership at the upper end of the distribution were related to even stronger team identification and a stronger indirect effect on reduced burnout.

Background: Recent research postulated that organizational identification plays an important role in employees' health and well-being. Building on the Social Identity Approach as a framework, we test the so-called social cure hypothesis, according to which group-based processes of social support should reduce employees' psychological distress., Design and Methods: While there is a considerable amount of cross-sectional evidence concerning the positive role played by organizational identification in this dynamic, there is a lack of full panel studies. This study tries to fill this gap by using data from a sample of technical and administrative staff of a University in Italy at three time points ( N  = 96). Data were analyzed using Autoregressive Cross-Lagged Panel models., Results: We found support for the hypothesized longitudinal mediational model. Specifically, strongly identified employees tend to receive more social support, and this in turn reduces psychological distress over time., Conclusions: This study is the first test of the social cure hypothesis in an organizational context that uses a panel study design. We discuss the theoretical and practical implications for management.

Background and Aims: We studied the quality of the job-related emotional experiences associated with work addiction. We hypothesized that work addiction would fuel both a higher level of daily job-related negative affect and a lower level of daily job-related positive affect and that such affective experiences would mediate the relationship between work addiction and emotional exhaustion reported at the end of the working day. Additionally, in light of typical behaviors and cognitions associated with work addiction, we also hypothesized that work addiction would modify the relationships between day workload and same day emotional strain reactions (i.e., job-related negative affect and job-related positive affect)., Methods: Participants were 213 workers (42.5% female), most of whom holding a high-profile job position, who were followed for 10 consecutive working days in the context of a daily diary study., Results: Multilevel analyses controlling for neuroticism revealed that work addiction was uniquely and positively related to daily job-related negative affect and that the latter mediated the relationship between work addiction and daily emotional exhaustion. On the other hand, work addiction was not negatively related to daily job-related positive affect; this relationship emerged only when removing neuroticism from the model. Additionally, work addiction strengthened the relationship between day workload and day job-related negative affect., Discussion: Results indicate that work addicted are characterized by the experience of a negatively connotated affect during work, and that this kind of affect may be a mechanism explaining the work addiction-burnout relationship.

In this study, we tested a theoretical model with moral disengagement, a mediator, and generalized social trust (GST), a mediator and a moderator of the relationship between personality traits and rule-respecting behaviors (i.e., social distancing and stay-at-home), during the coronavirus disease 2019 (COVID-19) outbreak in Italy. The data were collected on 1520 participants (61% males). General results are threefold: (1) moral disengagement mediated the relationship between emotional stability, narcissism, psychopathy, and social distancing; (2) among components of GST, trust in Government mediated the relationship between psychopathy and social distancing; trust in known others mediated the relationship between emotional stability, agreeableness, and Machiavellianism with total number of exits; trust in unknown others mediated the relationship of emotional stability, agreeableness, conscientiousness, and psychopathy with average daily number of exits; (3) GST moderated the indirect effect of personality traits on rule-respecting behaviors through moral disengagement. The theoretical and practical importance of these results is discussed., (Copyright © 2020 Alessandri, Filosa, Tisak, Crocetti, Crea and Avanzi.)

Workaholism and overcommitment are often used as interchangeable constructs describing an individual's over-involvement toward their own job. Employees with high levels in both constructs are characterized by an excessive effort and attachment to their job, with the incapability to detach from it and negative consequences in terms of poor health and job burnout. However, few studies have simultaneously measured both constructs, and their relationships are still not clear. In this study, we try to disentangle workaholism and overcommitment by comparing them with theoretically related contextual and personal antecedents, as well as their health consequences. We conducted a nonprobability mixed mode research design on 133 employees from different organizations in Italy using both self- and other-reported measures. To test our hypothesis that workaholism and overcommitment are related yet different constructs, we used partial correlations and regression analyses. The results confirm that these two constructs are related to each other, but also outline that overcommitment (and not workaholism) is uniquely related to job burnout, so that overcommitment rather than workaholism could represent the true negative aspect of work drive. Additionally, workaholism is more related to conscientiousness than overcommitment, while overcommitment shows a stronger relationship with neuroticism than workaholism. The theoretical implications are discussed.

There is strong and consistent evidence that identification with social groups is an important predictor of (ill-)health-related outcomes. However, the mediating mechanisms of the social identification-health link remain unclear. We present results from two studies, which aimed to test how perceived social support and collective self-efficacy mediate the effect of social identification on emotional exhaustion, chronic stress, and depressive symptoms. Study 1 (N = 180) employed a longitudinal two-wave design, whereas Study 2 (N = 100) used a field-experimental design with a manipulation of participants' social identity. Both studies consistently show that social identification was positively related to perceived social support, which, in turn, was positively associated with collective self-efficacy. Collective self-efficacy, finally, was negatively related to ill-health outcomes., (© 2018 The British Psychological Society.)

Safety performance is recognized as the more proximal and effective precursor of safety outcomes. In particular, safety compliance significantly reduces workplace accidents and injuries. However, it is not entirely clear what role organizational factors play in determining workers' safety. The present study contributes to defining which organizational factors increase safety compliance by testing a mediational model in which supervisor support is related to safety climate, which in turn is related to organizational identification that finally is related to safety compliance. We tested our hypotheses in a sample of 186 production workers of an Italian manufacturing firm using a cross-sectional design. Findings confirm our hypotheses. Management should consider these organizational factors in order to implement primary prevention practices against work accidents.

Nowadays organizations have to cope with two related challenges: maintaining an engaged and highly performing workforce and, at the same time, protecting and increasing employees' well-being and job satisfaction under conditions of a generalized increase of job demand, in an increasingly growing older population. According to the motivational process of the JD-R model, a work environment with many organizational resources will foster work engagement, which in turn will increase the likelihood of positive personal and organizational outcomes, such as job satisfaction, performance, and intention to stay. However, it is not clear how this motivational process could work in different age cohorts, as older workers may have different priorities to those of younger colleagues. Postulating the existence of a gain-cycle in the relationship between work engagement and outcomes, in this study we tested a longitudinal moderated mediation model in which job satisfaction increases over time through an increment in work engagement. We hypothesized that this process is moderated by job demand and aging. We collected data in public administrations in Northern Italy in order to measure work engagement and job satisfaction. 556 workers aged between 50 and 64 replied to the survey twice (the first time and 8 months later). The findings confirmed a moderated mediation model, in which job satisfaction at time 1 increased work engagement, which in turn fostered job satisfaction 8 months later, confirming the hypothesized gain-cycle. This relationship was shown to be moderated by the joint influence of job demand intensity and age: higher job demands and younger age are related to the maximum level of level gain cycle, while the same high level of job demands, when associated with older age, appears unable to stimulate a similar effect. The results confirm that, on one hand, older workers cannot be seen as a homogeneous group and, on the other hand, the importance of considering the role played by the gain cycle of resources. Our findings show that age matters, and that greater consideration should be devoted to age differences in order to design appropriate human resources practices that foster work engagement and satisfaction.

Background: Although it is widely acknowledged that in certain occupations emotional demands may be a critical phenomenon for workers' health, this has been traditionally taken for granted and their role in the stress process has not often been directly assessed., Objectives: To examine the relationship between emotional demands and mental distress, adjusting for the potential effect of common psychosocial factors (workload, job control, social support, role stressors, and poor relationships) and personal psychological factors (i.e. having been diagnosed with anxiety or depressive disorder)., Methods: A cross-sectional study on a sample of nurses of the National Healthcare Service was carried out (N = 256, 81.3% women). The psychosocial factors considered were assessed by means of widely known and validated scales. The examined health outcome (i.e. mental distress) was operationalized by means of the General Health Questionnaire (12-item version). Covariates: gender, age, tenure and shiftwork., Analyses: a series of logistic regressions., Results: Exposure to emotional demands was a risk factor for mental distress. The resulting risk was not altered when adjusting for other psychosocial and personal factors. In the final model emotional demands, workload and role stressors, in addition to having been diagnosed with anxiety or depressive disorder, were significant risk factors for nurses' mental distress., Conclusions: Emotional demands may substantially impact on nurses mental distress. These results give rise to concern in relation to work-stress prevention in certain professions, given that emotional demands are not included in the most common psychosocial risk assessment tools currently available, which may then miss identifying an important precondition of work stress.

Using the Conservation of Resources (COR) theory as a framework, we hypothesized a maladaptive role played by overcommitment in the escalation of burnout. We further specified our model by testing an interaction effect of job satisfaction. By using a longitudinal design, we proposed a moderated mediational model in which burnout at Time 1 (T1) increases overcommitment, which in turn leads to more burnout one month later. We further expected to find a moderating role of job satisfaction in the link between overcommitment and burnout at Time 2 (T2). A group of 86 white-collar workers in personnel services in Italy (longitudinal response rate = 77.48%) participated in our study. The findings supported our hypotheses even when controlling for gender and role stressors. In particular, by using bootstrapping procedures to test mediation, we found evidence that employees reporting burnout tend to develop a maladaptive coping style, i.e., overcommitment, which in turn increases burnout over time. This relation was particularly strong for dissatisfied employees. These results highlight the importance of overcommitment for burnout escalation, as well as of job satisfaction, since it may mitigate, at least in the short term, the effect of such dysfunctional strategies.

Pivotal role in atherogenesis is played by macrophages, which are early site for lipid accumulation and mediate the inflammatory and immune response in the intima. Epidemiological evidence indicates that natural antioxidants reduce the risk of heart disease, but, so far, supplementation studies have failed to confirm any protective effects of these compounds against cardiovascular disease. This study evaluated the effects of the natural antioxidant alpha-tocotrienol and of the newly designed compound, FeAOX-6, which combines antioxidant structural features of both tocopherols and carotenoids into a single molecule, on macrophage functions involved in foam cell formation. FeAOX-6 or alpha-tocotrienol induce a strong dose-dependent reduction of cholesterol and reduce cholesterol accumulation in human macrophages. The extent of the reduction found with alpha-tocotrienol was greater than that induced by FeAOX-6 and did not correlate with their respective antioxidant capacities. Treatment of HMDM with alpha-tocotrienol or FeAOX-6 enhanced also tumor necrosis factor-alpha secretion. These results are consistent with a reduction in scavenger receptor activity, but we found that antioxidant treatment did not affect cholesterol uptake from modified LDL. The effects on release on pro-inflammatory prostanoid precursors, PGE(2) and cytokine suggest a variety of metabolic responses that are both dependent on antioxidant compounds and macrophages activation status.

Oxidative stress plays a pivotal role in the pathogenesis of several chronic diseases and antioxidants may represent potential tools for the prevention of these diseases. Here, we investigated the antioxidant efficiency of different tocotrienol isoforms (alpha-, delta-, gamma-tocotrienols), and that of FeAox-6, a novel synthetic compound which combines, by a stable covalent bond, the chroman head of vitamin E and a polyisoprenyl sequence of four conjugated double bonds into a single molecule. The antioxidant efficiency was evaluated as the ability of the compounds to inhibit lipid peroxidation, reactive oxygen species (ROS) production, heat shock protein (hsp) expression in rat liver microsomal membranes as well as in RAT-1 immortalized fibroblasts challenged with different free radical sources, including 2,2'-azobis(2-amidinopropane) (AAPH), tert-butyl hydroperoxide (tert-BOOH) and H2O2. Our results show that individual tocotrienols display different antioxidant potencies. Irrespective of the prooxidant used, the order of effectiveness was:delta-tocotrienol > gamma-tocotrienol = alpha-tocotrienol in both isolated membranes and intact cells. This is presumably due to the decreased methylation of delta-tocotrienol chromane ring, which allows the molecule to be more easily incorporated into cell membranes. Moreover, we found that FeAox-6 showed an antioxidant potency greater than that of delta-tocotrienol. Such an efficiency seems to depend on the concomitant presence of a chromane ring and a phytyl chain in the molecule, which because of four conjugated double bonds, may induce a greater mobility and a more uniform distribution within cell membrane. In view of these results, FeAox-6 represents a new potential preventive agent in chronic diseases in which oxidative stress plays a pathogenic role.

In a previous study, the neuroprotection provided by some hindered phenols of synthetic nature and alpha-tocopherol in guinea-pig detrusor strips subjected to ischaemia/reperfusion-like conditions was shown to be related directly to the antioxidant activity. The aim of the present study was to estimate the capability of three novel chimeric molecules derived by assembling known antioxidant moieties, namely FeAOX-6, comprising a chromanyl head and the polyisoprenyl sequence characteristic for lycopene, FeCD-52, derived from the conjugation of ascorbic acid and a polyphenol moiety (FeRS-4) and FeDG-17, derived from the combination of ascorbic acid and a chromanyl head, to confer neuroprotection in an in vitro model of guinea-pig whole urinary bladder subjected to anoxia-glucopenia/reperfusion injury. The antioxidant potential of these compounds was determined by oxygen radical absorbance capacity (ORAC) and phochemiluminescence (PCL) assays to test their peroxyl and anion superoxide (O2(*-)) radical trapping activity, respectively. FeAOX-6, FeCD-52 and FeDG-17 exerted both strong neuroprotective and antioxidant activity, significantly higher than those exerted by the individual component moieties. The antioxidant activity of FeCD-52 was 37-fold higher than that of the reference compound trolox. FeAOX-6 exerted remarkable neuroprotective activity, superior to that of FeCD-52 or FeDG-17, in spite of its lower antioxidant activity. These findings indicate that assembling antioxidant moieties yields neuroprotective agents, the effectiveness of which, however, is not related to the antioxidant activity. It is possible that a different partitioning in cell compartments critically involved in the oxidative damage pathway plays a role in neuroprotection exerted by these compounds.

Several lines of evidence suggest potential benefits by a combination of carotenoids and tocopherols in chronic diseases. Therefore, we have designed FeAOX-6, a novel antioxidant that combines into a single molecule the chroman head of tocopherols and a fragment of lycopene, consisting of a polyisoprenyl sequence of four conjugated double bonds. The ability of FeAOX-6 in inhibiting lipid peroxidation and reactive oxygen species (ROS) production induced by different sources of free radicals (t-BOOH, AAPH, and H2O2) in arachidonic acid solution and in isolated thymocytes was investigated. Its antioxidant efficiency was also compared with that of alpha-tocopherol, lycopene, and a mixture of the two antioxidants. The results strongly suggest that FeAOX-6 can act as a potent antioxidant in our models, by inhibiting malondialdehyde production and ROS generation in a dose- and a time-dependent manner. In the cell model, the compound also provides a higher antioxidant capacity than alpha-tocopherol and lycopene, alone or in combination, suggesting the possibility of an oxidative intramolecular cooperation.