247 research outputs found
Epifluorescence microscopy imaging of phytoplasmas in embedded leaf tissues using DAPI and SYTO13 fluorochromes
The use of DNA-specific dyes, i. e. DAPI, is extensively reported for phytoplasma detection in fresh plant materials. However, fluorescence-based microscopy and imaging of fresh tissues often evidences technical limitations which are more significant in infected tissues, because phenolic and other defense-related compounds accumulate in the cell wall and in the vacuole making difficult sample preparation. In this paper we describe a method based on the use of epifluorescence microscopy and the DNA probes DAPI and SYTO13\uae for phytoplasma visualization in resin-embedded plant tissues. The method allows detection of phytoplasmas and it is recommended for tissues that are recalcitrant to conventional imaging
Phytoplasma infection in tomato is associated with re-organization of plasma membrane, ER stacks, and actin filaments in sieve elements
Phytoplasmas, biotrophic wall-less prokaryotes, only reside in sieve elements of their host plants. The essentials of the intimate interaction between phytoplasmas and their hosts are poorly understood, which calls for research on potential ultrastructural modifications. We investigated modifications of the sieve-element ultrastructure induced in tomato plants by ‘Candidatus Phytoplasma solani’, the pathogen associated with the stolbur disease. Phytoplasma infection induces a drastic re-organization of sieve-element substructures including changes in plasma membrane surface and distortion of the sieve-element reticulum. Observations of healthy and stolbur-diseased plants provided evidence for the emergence of structural links between sieve-element plasma membrane and phytoplasmas. One-sided actin aggregates on the phytoplasma surface also inferred a connection between phytoplasma and sieve-element cytoskeleton. Actin filaments displaced from the sieve-element mictoplasm to the surface of the phytoplasmas in infected sieve elements. Expression analysis revealed a decrease of actin and an increase of ER-resident chaperone luminal binding protein (BiP) in midribs of phytoplasma-infected plants. Collectively, the studies provided novel insights into ultrastructural responses of host sieve elements to phloem-restricted prokaryotes
Facing Loneliness and Anxiety During the COVID-19 Isolation: The Role of Excessive Social Media Use in a Sample of Italian Adults
The outbreak of coronavirus disease 2019 (COVID-19) prompted people to face a distressing and unexpected situation. Uncertainty and social distancing changed people's behaviors, impacting on their feelings, daily habits, and social relationships, which are core elements in human well-being. In particular, restrictions due to the quarantine increased feelings of loneliness and anxiety. Within this context, the use of digital technologies has been recommended to relieve stress and anxiety and to decrease loneliness, even though the overall effects of social media consumption during pandemics still need to be carefully addressed. In this regard, social media use evidence risk and opportunities. In fact, according to a compensatory model of Internet-related activities, the online environment may be used to alleviate negative feelings caused by distressing life circumstances, despite potentially leading to negative outcomes. The present study examined whether individuals who were experiencing high levels of loneliness during the forced isolation for COVID-19 pandemic were more prone to feel anxious, and whether their sense of loneliness prompted excessive social media use. Moreover, the potentially mediating effect of excessive social media use in the relationship between perceived loneliness and anxiety was tested. A sample of 715 adults (71.5% women) aged between 18 and 72 years old took part in an online survey during the period of lockdown in Italy. The survey included self-report measures to assess perceived sense of loneliness, excessive use of social media, and anxiety. Participants reported that they spent more hours/day on social media during the pandemic than before the pandemic. We found evidence that perceived feelings of loneliness predicted both excessive social media use and anxiety, with excessive social media use also increasing anxiety levels. These findings suggest that isolation probably reinforced the individuals' sense of loneliness, strengthening the need to be part of virtual communities. However, the facilitated and prolonged access to social media during the COVID-19 pandemic risked to further increase anxiety, generating a vicious cycle that in some cases may require clinical attention
Childhood emotional abuse and problematic social networking sites use in a sample of Italian adolescents: The mediating role of deficiencies in self-other differentiation and uncertain reflective functioning.
Childhood emotional abuse (CEA) is associated with various negative mental health outcomes. This study aimed to investigate the association between CEA and problematic social networking site (SNS) use in a sample of Italian adolescents.
Using structural equation modeling, the study examined whether the relationship between CEA and problematic SNS use was sequentially mediated by self-other differentiation and uncertain reflective functioning in 1308 Italian adolescents (628 males, age range 13-19 years).
A history of CEA was positively associated with problematic SNS use. Furthermore, deficiencies in self-other differentiation and uncertain reflective functioning partially mediated the relationship between CEA and problematic SNS use.
The present study provides additional insight into the psychological dynamics underpinning problematic SNS use among adolescents. The clinical implications of these findings are discussed
Childhood emotional abuse and problematic social networking sites use in a sample of Italian adolescents: The mediating role of deficiencies in self-other differentiation and uncertain reflective functioning
Objective: Childhood emotional abuse (CEA) is associated with various negative mental health outcomes. This study aimed to investigate the association between CEA and problematic social networking site (SNS) use in a sample of Italian adolescents. Design: Using structural equation modeling, the study examined whether the relationship between CEA and problematic SNS use was sequentially mediated by self-other differentiation and uncertain reflective functioning in 1308 Italian adolescents (628 males, age range 13–19 years). Results: A history of CEA was positively associated with problematic SNS use. Furthermore, deficiencies in self-other differentiation and uncertain reflective functioning partially mediated the relationship between CEA and problematic SNS use. Conclusions: The present study provides additional insight into the psychological dynamics underpinning problematic SNS use among adolescents. The clinical implications of these findings are discussed
Vulnerable Narcissism and Problematic Social Networking Sites Use: Focusing the Lens on Specific Motivations for Social Networking Sites Use
Research highlighted that Problematic Social Networking Sites Use (PSNSU) and vulnerable narcissism are associated. However, the mechanisms underlying this relationship are still unclear. The present study aimed to test the mediating role of motives for social networking sites (SNSs) use between vulnerable narcissism and five symptoms of PSNSU (i.e., preference for online social interactions, mood regulation, cognitive preoccupation, compulsive use, and negative outcomes) in a sole model. Self-report questionnaires were completed by 344 SNSs users in the age range of 18–30 years (76.5% females; mean age = 23.80 years, standard deviation = 2.30 years). Vulnerable narcissism, three motives to use SNSs (coping, conformity, enhancement), and symptoms of PSNSU were assessed. Structural equation modeling was used to test for mediation. The results indicate that both motives with positive (i.e., enhancement) and negative (i.e., coping and conformity) valence partially mediated the association between vulnerable narcissism and different symptoms of PSNSU. We conclude that individuals with vulnerable narcissism may develop PSNSU not only as a compensatory strategy to cope with psychosocial difficulties but also as a result of a gratification-seeking process
The Doctor Is In(ternet): The Mediating Role of Health Anxiety in the Relationship between Somatic Symptoms and Cyberchondria
Cyberchondria is a dysfunctional behavioral pattern characterized by an excessive and anxiety-amplifying engagement in searching for reassuring health information on the Internet. Research demonstrated that somatic symptoms and health anxiety might foster maladaptive health-related behaviors, such as cyberchondria. However, the relationships between somatic symptoms, health anxiety, and cyberchondria have been scarcely examined. Accordingly, this study aimed to test the mediating effect of health anxiety on the association between somatic symptoms and cyberchondria. Four hundred and thirty-one adults from the community (158 males, 36.66%), aged between 18 and 74, were recruited via an online survey. Participants completed self-report measures of somatic symptoms, health anxiety, and cyberchondria. A mediation analysis demonstrated that the severity of somatic symptoms predicted increased levels of cyberchondria and that health anxiety partially mediated this association. Therefore, interventions aimed at decreasing health anxiety may also play a role in decreasing the risk of developing cyberchondria
Language-Related Skills in Bilingual Children With Specific Learning Disorders
Purpose: The purpose of this study is to better understand the characteristics of the language-related skills of bilingual children with specific learning disorders (SLD). The aim is achieved by analyzing language-related skills in a sample of bilingual (Italian plus another language) and Italian monolingual children, with and without SLD. Patients and methods: A total of 72 minors aged between 9 and 11 were recruited and divided into four groups: 18 Italian monolingual children with SLD, 18 bilingual children with SLD, 18 Italian monolingual children without SLD, and 18 bilingual children without SLD. Each child underwent tests to evaluate different aspects of language skills: lexical and grammar, metalanguage and executive functions. Results: With regard to lexical and grammatical skills, the conditions of SLD and bilingualism both impact naming in terms of total number of errors for words with low frequency of use, while the condition of SLD has an effect on semantic errors for words with low frequency of use. The condition of bilingualism impacts on the total errors for words with high frequency of use and on circumlocution-type errors for words with low frequency of use. There were significant effects of bilingualism and SLD on the metalinguistic test for understanding implicit meaning, and an impact of SLD on phonological awareness was also found. Conclusion: The results suggest that both SLD and bilingualism have an effect on some lexical skills, in particular for words with low frequency of use. Both conditions, bilingualism and SLD, seem to impact on metalinguistic abilities that depend on lexical knowledge. These findings reinforce the importance of improving understanding of the neuropsychological profile of bilingual children with SLD
Deconstructing the components model of addiction: an illustration through "addictive" use of social media.
The components model of addiction posits that all addictions share six components, namely salience, tolerance, mood modification, relapse, withdrawal, and conflict. This highly influential model has resulted in the development of numerous psychometric instruments that measure addictive behaviors according to these criteria. However, recent research suggests that, in the context of behavioral addictions, certain components constitute peripheral features that do not distinguish non-pathological from pathological behavior. Using "addictive" use of social media as a representative example, we examined this perspective by testing whether these six components actually assess central features of addiction, or whether some of them constitute peripheral features that are not indicative of a disorder. Four independent samples totaling 4,256 participants from the general population completed the Bergen Social Media Addiction Scale, a six-item psychometric instrument derived from the components model of addiction to assess social media "addiction". By performing structural equation modeling and network analyses, we showed that the six components did not form a unitary construct and, crucially, that some components (i.e., salience, tolerance) were not associated with measures assessing psychopathological symptoms. Taken together, these results suggest that psychometric instruments based on the components model conflate central and peripheral features of addiction when applied to behavioral addictions. This implies that such instruments pathologize involvement in appetitive behaviors. Our findings thus call for renewing the conceptualization and assessment of behavioral addictions
Further evidence for the bidimensionality of the components model of addiction: a reply to Amendola (2023)
In our original research article entitled “Deconstructing the components model of addiction: an illustration through “addictive” use of social media” (Fournier et al., 2023), we showed that the Bergen Social Media Addiction Scale, a six-item psychometric instrument derived from the components model of addiction to assess social media “addiction”, did not form a unitary, but a bidimensional construct in which some components (i.e., salience, tolerance) were not associated with psychopathological symptoms, thus conflating central and peripheral features of addiction. Subsequently, in a recent commentary, Amendola (2023) sought to determine whether our findings were driven by the use of data aggregated from multiple independent datasets, i.e., a decision we transparently acknowledged as a limitation in our original research article. Following their re-analysis, Amendola (2023) claimed to have demonstrated that a unidimensional model best fitted the data. However, they only reported results for a partial set of models relevant to this investigation. In the present reply, through a transparent assessment and reporting of all unidimensional and bidimensional models relevant to this investigation, we show that the bidimensionality of the Bergen Social Media Addiction Scale is, in fact, tenable, robust, and consistent across multiple independent datasets. In line with the growing evidence demonstrating that many sets of criteria involved in operationalizing behavioral addictions pathologize involvement in appetitive behaviors, these results highlight the necessity to renew the conceptualization and assessment of behavioral addictions
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