Crise suicidaire et maladie d’Alzheimer débutante : intérêt d’une analyse neuropsychologique détaillée

RésuméIntroduction Le risque de développer une maladie d’Alzheimer augmente avec l’âge. Le rôle de celle-ci comme un facteur de risque indépendant de suicide n’est pas bien compris et demeure complexe et mal élucidé. L’objectif de cet article est d’envisager une compréhension neuropsychologique de la crise suicidaire dans le cas d’une maladie d’Alzheimer débutante. Méthode Une évaluation cognitive globale (Mini-Mental State Examination, Batterie Rapide d’Évaluation Frontale) complétée de l’exploration de l’inhibition cognitive selon ses fonctions d’accès (tâche de lecture en présence de distracteurs), de suppression (Trail Making Test), et de freinage (Stroop, Hayling, Go/No-Go) a été réalisée chez une femme souffrant d’une maladie d’Alzheimer (MMSE à 21/30) avant et après réalisation d’une tentative de suicide dans un contexte de dépression. Résultats L’échelle d’Hamilton était cotée à 24/52, l’échelle de dépression de Cornell à 21/38. L’intentionnalité suicidaire était modérée avec un score à 15/25 à l’échelle d’intentionnalité suicidaire de Beck. Initialement préservées, le déclin des fonctions exécutives a coïncidé avec l’émergence d’une crise suicidaire dans un contexte de dépression chez une patiente souffrant de maladie d’Alzheimer. Les fonctions de l’inhibition cognitive étaient altérées dans ses trois composantes, après ajustement des facteurs de confusion. Conclusion Une évaluation détaillée des fonctions exécutives et singulièrement de l’inhibition cognitive dans la population des patients atteints d’une maladie d’Alzheimer permettrait de détecter les personnes les plus à risque de passage à l’acte et de proposer une surveillance plus étroite dans le cadre des soins généraux de leur maladie. AbstractIntroduction The role of Alzheimer\u27s disease as a risk factor for suicide is unclear. The aim of this study was to understand neuropsychological component of the suicidal crisis in Alzheimer\u27s disease. Method Using an extensive neuropsychological battery, different aspects of cognitive inhibition were particularly examined: Access to relevant information (using the Reading with distraction task), suppression of no longer relevant information (Trail Making Test, Rule Shift Cards), and restraint of cognitive resources to relevant information (Stroop test, Hayling Sentence Completion test, Go/No-Go). One female Alzheimer depressed case was assessed before and after a suicide attempt. Results Ten days after the patient\u27s suicide attempt, dementia was still moderate with a MMSE score at 21/30 but with a worsening of executive functions (FAB at 8/18) in the context of depression and suicide. The Hamilton-Depression Rating Scale was at 24 (maximal score at 52), and the Cornell Scale for Depression was at 21 (maximal score at 38). Suicidal intent was moderate with a score of 9 on the Beck Suicide Intent Scale (maximal score at 25). The patient did not present a delirium, psychotic symptoms, or anosognosia. Her episodic memory was altered as shown by her semantic performance on verbal fluency (naming 12 animals in 120 seconds) and on lexical fluency (naming 8 words beginning with the letter P). Initially preserved, executive function declined during a suicidal crisis in a context of depression in Alzheimer\u27s disease case. Neuropsychological testing confirmed a dysexecutive syndrome (FAS at 8/18), with an impairment in her conceptualization capacity (MCST) and a deficit in cognitive inhibition and its access (reading task in the presence of distractors), deletion (TMT) and restraint (Stroop, Go/No-Go, Hayling) functions. Computed tomography has shown no signs of intracranial expansive process. Conclusion Assessing predictors of suicide and means of completion in patients with dementia may help the development of interventions to reduce risk of suicide among the growing population of individuals with dementia. Because of Alzheimer\u27s-related cognitive inhibition impairment, identification and intervention addressing the complex issues of depression, executive dysfunction and dementia may help clinicians to mitigate the risk of suicide in patients with Alzheimer\u27s disease

YouTube, Social Norms and Perceived Salience of Climate Change in the American Mind

This online experiment explored how contextual information embedded in new media channels such as YouTube may serve as normative social cues to users. Specifically, we examined whether the number of views listed under a YouTube video about climate change would elicit inferences regarding how “others” feel about the climate issue and, consequently, might influence perceptions of issue salience. Participants in this experiment were exposed to a YouTube video about climate change using two experimental conditions, one providing a small number of views under the video and the second listing a large number of views. Results suggest that the “number of views” cue did, indeed, influence participant perceptions of the importance assigned by other Americans to the issue of climate change. Further, compared to low self-monitoring participants, high self-monitoring participants registered an increase in their own judgment of issue importance

Vector Competence of Ixodes scapularis and Ixodes ricinus (Acari: Ixodidae) for Three Genospecies of Borrelia burgdorferi

The vector competence of 2 tick species, Ixodes ricinus (L.) and Ixodes scapularis Say, was determined and compared for 3 genospecies of Borrelia burgdorferi. The 3 genospecies of B. burgdorferi used in the following experiments were Borrelia burgdorferi sensu stricto (B-31 and B-31.D1 clone), Borrelia afzelii (strain Pgau.C3), and Borrelia garinii (strain VS286 and VSBP). Spirochetes from all 5 strains were inoculated intradermally into outbred mice; larval ticks of both species were subsequently fed on those mice and replete larvae were assayed for infection by culture in BSK-H media every 7 d for 4 wk. Infection frequencies in I. scapularis exposed to the 5 strains were as follows: B-31 (90%), B-31.D1 (83%), Pgau.C3 (87%), VS286 (10%), and VSBP (5%). The comparable infection frequencies for /. ricinus were B-31 (3%), B-31.D1 (3%), Pgau.C3 (90%), VS286 (5%), and VSBP (3%). Resultant nymphal /. scapularis successfully transmitted B-31, B-31.D1, Pgau.C3, and VS286 to outbred mice. /. ricinus nymphs transmitted Pgau.C3 and VS286. Both species failed to transmit strain VSB

Superconducting pairing and density-wave instabilities in quasi-one-dimensional conductors

Using a renormalization group approach, we determine the phase diagram of an extended quasi-one-dimensional electron gas model that includes interchain hopping, nesting deviations and both intrachain and interchain repulsive interactions. d-wave superconductivity, which dominates over the spin-density-wave (SDW) phase at large nesting deviations, becomes unstable to the benefit of a triplet $f$-wave phase for a weak repulsive interchain backscattering term $g_1^\perp>0$, despite the persistence of dominant SDW correlations in the normal state. Antiferromagnetism becomes unstable against the formation of a charge-density-wave state when $g_1^\perp$ exceeds some critical value. While these features persist when both Umklapp processes and interchain forward scattering ($g_2^\perp$) are taken into account, the effect of $g_2^\perp$ alone is found to frustrate nearest-neighbor interchain $d$- and $f$-wave pairing and instead favor next-nearest-neighbor interchain singlet or triplet pairing. We argue that the close proximity of SDW and charge-density-wave phases, singlet d-wave and triplet $f$-wave superconducting phases in the theoretical phase diagram provides a possible explanation for recent puzzling experimental findings in the Bechgaard salts, including the coexistence of SDW and charge-density-wave phases and the possibility of a triplet pairing in the superconducting phase.Comment: 19 pages, 13 figure

Magnetic-field-induced superconductivity in layered organic molecular crystals with localized magnetic moments

The synthetic organic compound lambda-(BETS)2FeCl4 undergoes successive transitions from an antiferromagnetic insulator to a metal and then to a superconductor as a magnetic field is increased. We use a Hubbard-Kondo model to clarify the role of the Fe(3+) magnetic ions in these phase transitions. In the high-field regime, the magnetic field acting on the electron spins is compensated by the exchange field He due to the magnetic ions. This suggests that the field-induced superconducting state is the same as the zero-field superconducting state which occurs under pressure or when the Fe(3+) ions are replaced by non-magnetic Ga(3+) ions. We show how He can be extracted from the observed splitting of the Shubnikov-de Haas frequencies. Furthermore, we use this method of extracting He to predict the field range for field-induced superconductivity in other materials.Comment: 5 page

Planck pre-launch status: HFI beam expectations from the optical optimisation of the focal plane

Planck is a European Space Agency (ESA) satellite, launched in May 2009, which will map the cosmic microwave background anisotropies in intensity and polarisation with unprecedented detail and sensitivity. It will also provide full-sky maps of astrophysical foregrounds. An accurate knowledge of the telescope beam patterns is an essential element for a correct analysis of the acquired astrophysical data. We present a detailed description of the optical design of the High Frequency Instrument (HFI) together with some of the optical performances measured during the calibration campaigns. We report on the evolution of the knowledge of the pre-launch HFI beam patterns when coupled to ideal telescope elements, and on their significance for the HFI data analysis procedure

Environmental Impacts and Their Association With Performance and Excretion Traits in Growing Pigs

The selection of pigs for improved production traits has been, for a long time, the major driver of pig breeding. More recently, because of the increasing concern with the environment, new selection criteria have been explored, such as nitrogen (N) excretion. However, many studies indicate that life cycle assessment (LCA) provides much better indicators of environmental impacts than excretion. Therefore, the objective of this study was to investigate, using a modeling approach, the relationships between production traits and LCA impacts of individual growing pigs calculated at the farm gate for 1 kg of body weight gain. Performances of pigs were simulated for 2-phase (2P) and precision feeding (PR), using the InraPorc population model (on 1,000 pigs). Nitrogen excretion was positively correlated with feed conversion ratio (FCR; r = +0.96), climate change (CC; r = +0.96), acidification potential (AC; r = +0.97), eutrophication potential (EU; r = +0.97), and land occupation (LO; r = +0.96), whatever the feeding program. However, FCR appeared to be a better indicator of LCA impacts, with very high and positive correlations (r > +0.99) with CC, AC, EU, and LO for both feeding programs. The CC, AC, and EU impacts of pig production for PR feeding were 1.3, 10, and 7.5% lower than for 2P, respectively, but the correlations within each outcome were very similar among feeding programs. It was concluded that the use of FCR as a selection criterion in pig breeding seems to be a promising approach to associate improved performance and low environmental impact of pig fattening

The changing information environment for nanotechnology: online audiences and content

The shift toward online communication in all realms, from print newspapers to broadcast television, has implications for how the general public consumes information about nanotechnology. The goal of this study is threefold: to investigate who is using online sources for information and news about science and nanotechnology, to examine what the general public is searching for online with regards to nanotechnology, and to analyze what they find in online content of nanotechnology. Using survey data, we find those who report the Internet as their primary source of science and technology news are diverse in age, more knowledgeable about science and nanotechnology, highly educated, male, and more diverse racially than users of other media. In a comparison of demographic data on actual visits by online users to general news and science Web sites, science sites attracted more male, non-white users from the Western region of the United States than news sites did. News sites, on the other hand, attracted those with a slightly higher level of education. Our analysis of published estimates of keyword searches on nanotechnology reveals people are turning to the Internet to search for keyword searches related to the future, health, and applications of nanotechnology. A content analysis of online content reveals health content dominates overall. Comparisons of content in different types of sites—blogs, government, and general sites—are conducted