503 research outputs found
Aluminum work function: Effect of oxidation, mechanical scraping and ion bombardment
Surface studies have been performed on aluminum polycrystalline surfaces which have been mechanically scraped. Such studies were initiated in order to understand surface effects occurring in tribological processes which involve rubbing surfaces and the effects of adsorption of oxygen. To characterize the surfaces, the following three different experimental approaches have been used: (1) X.P.S. (X-ray photoelectron spectroscopy), in order to check the cleanliness of the surfaces and follow the adsorption and oxidation kinetics; (2) Analysis of the work function changes by following the energy spectra of secondary electrons emitted under low energy electron bombardment; and (3) Analysis of photoemission intensities under U.V. excitation. The reference state being chosen to be the surface cleaned by ion bombardment and exposures to oxygen atmospheres have been shown to lower the work function of clean polycrystalline aluminum by 1.2 eV. The oxygen pressure is found to affect only the kinetics of these experiments. Mechanical scraping has been shown to induce a decrease ( 0.3 eV) in the work function, which could sharply modify the kinetics of adsorption on the surface
Mémoire émotionnelle du soi
International audienceLes émotions structurent la mémoire autobiographique (MA) en distinguant les événements importants pour le soi narratif, c'est-à-dire pour la poursuite de buts à long terme. Le rappel en MA est un processus de reconstruction qui fournit au soi une trame narrative cohérente dans le temps à l'origine d'un sentiment d'identité. Alors que le cortex préfrontal sous-tend les processus de reconstruction et de référence à soi, respectivement par ses régions latérales et médiales, le cortex temporal sous-tend les aspects sémantiques et épisodiques du rappel en MA, respectivement par ses régions latérales et médiales. De plus, les structures corticales médianes postérieures et l'amygdale sont impliquées dans les aspects visuels et émotionnels du souvenir. Toutes ces régions ont un fonctionnement anormal dans la dépression majeure, qui, sans surprise, est associé à des troubles de la MA combinant congruence à l'humeur, surgénéralisation, souvenirs intrusifs et perspective visuelle à la troisième personne
Usefulness of a single-item measure of depression to predict mortality: the GAZEL prospective cohort study.: single-item of depression and mortality
International audienceBACKGROUND: It remains unknown whether short measures of depression perform as well as long measures in predicting adverse outcomes such as mortality. The present study aims to examine the predictive value of a single-item measure of depression for mortality. METHODS: A total of 14,185 participants of the GAZEL cohort completed the 20-item Center-for-Epidemiologic-Studies-Depression (CES-D) scale in 1996. One of these items (I felt depressed) was used as a single-item measure of depression. All-cause mortality data were available until 30 September 2009, a mean follow-up period of 12.7 years with a total of 650 deaths. RESULTS: In Cox regression model adjusted for baseline socio-demographic characteristics, a one-unit increase in the single-item score (range 0-3) was associated with a 25% higher risk of all-cause mortality (95% CI: 13-37%, P<0.001). Further adjustment for health-related behaviours and physical chronic diseases reduced this risk by 36% and 8%, respectively. After adjustment for all these variables, every one-unit increase in the single-item score predicted a 15% increased risk of death (95% CI: 5-27%, P<0.01). There is also an evidence of a dose-reponse relationship between reponse scores on the single-item measure of depression and mortality. CONCLUSION: This study shows that a single-item measure of depression is associated with an increased risk of death. Given its simplicity and ease of administration, a very simple single-item measure of depression might be useful for identifying middle-aged adults at risk for elevated depressive symptoms in large epidemiological studies and clinical settings
Serotonin and norepinephrine reuptake inhibitors antidepressant use is related to lower baroreflex sensitivity independently of the severity of depressive symptoms. A community-study of 9213 participants from the Paris Prospective Study III
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The Queen and I: Neural Correlates of Altered Self-Related Cognitions in Major Depressive Episode
BACKGROUND: Pervasive negative thoughts about the self are central to the experience of depression. Brain imaging studies in the general population have localised self-related cognitive processing to areas of the medial pre-frontal cortex. AIMS: To use fMRI to compare the neural correlates of self-referential processing in depressed and non-depressed participants. METHOD: Cross-sectional comparison of regional activation using Blood Oxygen Level Dependent (BOLD) fMRI in 13 non-medicated participants with major depressive episode and 14 comparison participants, whilst carrying out a self-referential cognitive task. RESULTS: Both groups showed significant activation of the dorsomedial pre-frontal cortex and posterior cingulate cortex in the 'self-referent' condition. The depressed group showed significantly greater activation in the medial superior frontal cortex during the self-referent task. No difference was observed between groups in the 'other-referent' condition. CONCLUSIONS: Major depressive episode is associated with specific neurofunctional changes related to self-referential processing
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Cardiovascular disease: The effect of erectile dysfunction on adherence to cardiovascular disease medication
Due to their similar aetiologies, cardiovascular disease (CVD) and erectile dysfunction (ED) are closely linked, with the prevalence of ED being approximately 75% for individuals at high risk of CVD. ED can have a detrimental effect on quality of life not only for the individual but also his sexual partner which in turn impacts upon their intimate relationship. Some CVD medications have been found to have a negative effect on erectile function and therefore act as an influential factor for the cessation of important CVD medication. Low adherence to CVD medication has been linked to increased health costs, hospitalizations and importantly, a higher risk of mortality. Research has shown that men find it difficult to seek medical help in relation to ED which is also compounded by the notion that health care providers do not address sexual issues adequately. Patients' beliefs about CVD medication are modifiable and therefore an opportunity exists not only for health care providers to facilitate discussions in relation to ED and medication adherence but also encompass an opportunity to increase adherence to CVD medication through intervention
Association of hearing impairment with incident depressive symptoms: a community-based prospective study
Objective: The aim was to investigate the potential association between hearing impairment and incident depressive symptoms.Methods: Using a prospective community-based cohort study in France (the Paris Prospective Study III), participants aged 50-75 years were recruited between 2008 and 2012 and thereafter followed up every 2 years up to 2018. Hearing impairment, measured at study recruitment by audiometry testing, was defined as a pure tone average >25 decibels in the better ear. Incident depressive symptoms, measured using the validated 13-item Questionnaire of Depression 2nd version, was assessed during follow-up. Multivariate generalized estimating equations were used to compute odds ratio (OR) and 95% confidence intervals (CI).Results: Among 7591 participants free of depressive symptoms at baseline (mean age 59.8 years, 63% of men), 14.3% had hearing impairment. Over 6 years of follow-up, 479 subjects (6.3%) had incident depressive symptoms. The OR for incident depressive symptoms was 1.36 for subjects with baseline hearing impairment (95% CI, 1.06-1.73). A pooled analysis of 4 published prospective studies yielded a multivariable relative risk of baseline hearing impairment for incident depressive symptoms of 1.29 (95% CI, 1.09-1.53).Conclusions: In this community-based prospective cohort study of participants aged 50 to 75 years, baseline hearing impairment was associated with a 36% increased odds of incident depressive symptoms
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Whole-brain functional connectivity during emotional word classification in medication-free Major Depressive Disorder: abnormal salience circuitry and relations to positive emotionality
Major Depressive Disorder (MDD) has been associated with biased processing and abnormal regulation of negative and positive information, which may result from compromised coordinated activity of prefrontal and subcortical brain regions involved in evaluating emotional information. We tested whether patients with MDD show distributed changes in functional connectivity with a set of independently derived brain networks that have shown high correspondence with different task demands, including stimulus salience and emotional processing. We further explored if connectivity during emotional word processing related to the tendency to engage in positive or negative emotional states. In this study, 25 medication-free MDD patients without current or past comorbidity and matched controls (n=25) performed an emotional word-evaluation task during functional MRI. Using a dual regression approach, individual spatial connectivity maps representing each subject’s connectivity with each standard network were used to evaluate between-group differences and effects of positive and negative emotionality (extraversion and neuroticism, respectively, as measured with the NEO-FFI). Results showed decreased functional connectivity of the medial prefrontal cortex, ventrolateral prefrontal cortex, and ventral striatum with the fronto-opercular salience network in MDD patients compared to controls. In patients, abnormal connectivity was related to extraversion, but not neuroticism. These results confirm the hypothesis of a relative (para)limbic-cortical decoupling that may explain dysregulated affect in MDD. As connectivity of these regions with the salience network was related to extraversion, but not to general depression severity or negative emotionality, dysfunction of this network may be responsible for the failure to sustain engagement in rewarding behavior
COVID-19-related consultation-liaison (CL) mental health services in general hospitals: A perspective from Europe and beyond
Objective: The COVID-19 pandemic posed new challenges for integrated health care worldwide. Our study aimed to describe newly implemented structures and procedures of psychosocial consultation and liaison (CL) services in Europe and beyond, and to highlight emerging needs for co-operation. Methods: Cross-sectional online survey from June to October 2021, using a self-developed 25-item questionnaire in four language versions (English, French, Italian, German). Dissemination was via national professional societies, working groups, and heads of CL services. Results: Of the participating 259 CL services from Europe, Iran, and parts of Canada, 222 reported COVID-19 related psychosocial care (COVID-psyCare) in their hospital. Among these, 86.5% indicated that specific COVID-psyCare co-operation structures had been established. 50.8% provided specific COVID-psyCare for patients, 38.2% for relatives, and 77.0% for staff. Over half of the time resources were invested for patients. About a quarter of the time was used for staff, and these interventions, typically associated with the liaison function of CL services, were reported as most useful. Concerning emerging needs, 58.1% of the CL services providing COVID-psyCare expressed wishes for mutual information exchange and support, and 64.0% suggested specific changes or improvements that they considered essential for the future. Conclusion: Over 80% of participating CL services established specific structures to provide COVID-psyCare for patients, their relatives, or staff. Mostly, resources were committed to patient care and specific interventions were largely implemented for staff support. Future development of COVID-psyCare warrants intensified intra- and inter-institutional exchange and co-operation
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