Acceleration of Plasma Flows Due to Reverse Dynamo Mechanism

The "reverse-dynamo" mechanism - the amplification/generation of fast plasma flows by micro scale (turbulent) magnetic fields via magneto-fluid coupling is recognized and explored. It is shown that macro-scale magnetic fields and flows are generated simultaneously and proportionately from micro scale fields and flows. The stronger the micro-scale driver, the stronger are the macro-scale products. Stellar and astrophysical applications are suggested.Comment: 16 pages including 3 figures. The Astrophys. J. (accepted); additional material is given for clarification; terminology is change

On a mechanism for enhancing magnetic activity in tidally interacting binaries

We suggest a mechanism for enhancing magnetic activity in tidally interacting binaries. We suppose that the deviation of the primary star from spherical symmetry due to the tidal influence of the companion leads to stellar pulsation in its fundamental mode. It is shown that stellar radial pulsation amplifies torsional Alfv{\'e}n waves in a dipole-like magnetic field, buried in the interior, according to the recently proposed swing wave-wave interaction (Zaqarashvili 2001). Then amplified Alfv{\'e}n waves lead to the onset of large-scale torsional oscillations, and magnetic flux tubes arising towards the surface owing to magnetic buoyancy diffuse into the atmosphere producing enhanced chromospheric and coronal emission.Comment: Accepted in Ap

The Naked Truth: The Face and Body Sensitive N170 Response Is Enhanced for Nude Bodies

Recent event-related potential studies have shown that the occipitotemporal N170 component - best known for its sensitivity to faces - is also sensitive to perception of human bodies. Considering that in the timescale of evolution clothing is a relatively new invention that hides the bodily features relevant for sexual selection and arousal, we investigated whether the early N170 brain response would be enhanced to nude over clothed bodies. In two experiments, we measured N170 responses to nude bodies, bodies wearing swimsuits, clothed bodies, faces, and control stimuli (cars). We found that the N170 amplitude was larger to opposite and same-sex nude vs. clothed bodies. Moreover, the N170 amplitude increased linearly as the amount of clothing decreased from full clothing via swimsuits to nude bodies. Strikingly, the N170 response to nude bodies was even greater than that to faces, and the N170 amplitude to bodies was independent of whether the face of the bodies was visible or not. All human stimuli evoked greater N170 responses than did the control stimulus. Autonomic measurements and self-evaluations showed that nude bodies were affectively more arousing compared to the other stimulus categories. We conclude that the early visual processing of human bodies is sensitive to the visibility of the sex-related features of human bodies and that the visual processing of other people's nude bodies is enhanced in the brain. This enhancement is likely to reflect affective arousal elicited by nude bodies. Such facilitated visual processing of other people's nude bodies is possibly beneficial in identifying potential mating partners and competitors, and for triggering sexual behavior

Promoting Functional Health in Midlife and Old Age: Long-Term Protective Effects of Control Beliefs, Social Support, and Physical Exercise

Previous studies have examined physical risk factors in relation to functional health, but less work has focused on the protective role of psychological and social factors. We examined the individual and joint protective contribution of control beliefs, social support and physical exercise to changes in functional health, beyond the influence of health status and physical risk factors in middle-aged and older adults. Given that functional health typically declines throughout adulthood, it is important to identify modifiable factors that can be implemented to maintain functioning, improve quality of life, and reduce disability.We conducted a national longitudinal study, Midlife in the United States (MIDUS), with assessments in 1995-1996 and 2004-2006, and 3,626 community-residing adults, aged 32 to 84, were included in the analyses. Functional health (Physical Functioning subscale of the SF-36) and protective factors were measured at both occasions. While controlling for socio-demographic, health status, and physical risk factors (large waist circumference, smoking, and alcohol or drug problems), a composite of the three protective variables (control beliefs, social support, and physical exercise) at Time 1 was significantly related to functional health change. The more of these factors at Time 1, the better the health maintenance over 10 years. Among middle-aged and older adults, declines in health were significantly reduced with an increased number of protective factors.Age-related declines in health were reduced among those with more protective factors up to a decade earlier in life. Modifiable psychological, social, and physical protective factors, individually and in the aggregate, are associated with maintenance of functional health, beyond the damaging effects of physical risk factors. The results are encouraging for the prospect of developing interventions to promote functional health and for reducing public health expenditures for physical disability in later life

Search for the Structure of a Sulfur-Induced Reconstruction on Cu(111)

We have carried out an extensive DFT-based search for the structure of the (√43 × √43)R ± 7.5° reconstruction of S on Cu(111), which exhibits a honeycombtype structure in scanning tunneling microscopy (STM). We apply two criteria in this search: The structure must have a reasonably low chemical potential, and it must provide a good match with STM data, both our own and the data published by Wahlström et al. Phys. Rev. B 1999, 60, 10699. The best model has 12 S adatoms and 9 Cu adatoms per unit cell. Local defects within the Cu9S12 framework, consisting of one missing or one extra Cu adatom per unit cell, would be difficult to detect with STM and would not be energetically costly. There is no obvious correlation between this model and the structure of bulk CuS. If the √43 reconstruction is viewed in terms of local building blocks, then CuS3 and CuS2 clusters, linked by shared S atoms, provides the best description.Reprinted (adapted) with permission from Journal of Physical Chemistry C 118 (2014): 29218, doi: 10.1021/jp505351g. Copyright 2014 American Chemical Society.</p

Schéma de niveaux de 223Ra III. Etude des coincidences γ * γ et des vies moyennes

Description of the multidimensional (1 024 x 1 024 channels) study of γ * γ coïncidences in 223Ra is given. After numerical treatment of the data, existence, attribution and intensities of about 50 transitions have been established. Mean lives, longer than 30 to 80 ps, have been determined by means of a method based on the emission of γ rays by atoms in flight after α-recoil. A substantial amount of transition probabilities is so obtained, and this appears as an important factor for the discussion of the level scheme, to be given later.L'étude multidimensionnelle, en 1 024 x 1 024 canaux, des cascades de rayonnements dans 223Ra est décrite. Par un traitement quantitatif approprié, les incertitudes concernant l'existence, l'emplacement, l'intensité d'une cinquantaine de transitions ont pu être levées. Les vies moyennes supérieures à une cinquantaine de picosecondes ont été déterminées au moyen d'une méthode, nouvelle pour les émetteurs α, et qui utilise l'émission des rayonnements γ par les atomes en vol à la suite du recul α. Ceci mène à la connaissance d'un grand nombre de probabilités de transition, ce qui constitue un des facteurs indispensables à une discussion du schéma qui sera donnée ultérieurement dans cette série d'articles