Search results for "ORIENTATION"

Analysis of a spatial orientation memory in Drosophila.

2008

Flexible goal-driven orientation requires that the position of a target be stored, especially in case the target moves out of sight. The capability to retain, recall and integrate such positional information into guiding behaviour has been summarized under the term spatial working memory. This kind of memory contains specific details of the presence that are not necessarily part of a long-term memory. Neurophysiological studies in primates indicate that sustained activity of neurons encodes the sensory information even though the object is no longer present. Furthermore they suggest that dopamine transmits the respective input to the prefrontal cortex, and simultaneous suppression by GABA s…

Three-dimensional Hall effect accelerometer for recording head movements of freely moving laboratory animals

1991

A Hall effect device was constructed for a measurement of head movements in three spatial dimensions during classical conditioning experiments in cats. A Hall sensor was used to detect movements of a magnetic fragment floating in a small (15 x 15 mm) cube. The magnetic fragment was kept in the centre of the sealed cube with a thin coil spring which was filled with thin oil for damping excessive afteroscillations. A comparison of this device to a commercial accelerometer showed that the accuracy of the Hall device is sufficient for the movement recordings and that the device is sensitive also to slowly accelerating movements. The construction is compact and can be easily mounted, for example…

Synthesis of pyrido[2,3-d]pyrimidinones by the reaction of aminopyrimidin-4-ones with benzylidene meldrum's acid derivatives

1997

A series of pyrido[2,3-d]pyrimidine-4,7-diones 5a-h were prepared from 6-amino-4-pyrimidones 1 and benzylidene Meldrum's acid derivatives 2 by cyclization reactions in boiling nitrobenzene. The structure of 5, determined by nmr measurements, reveals a selective orientation of 1 and 2 in the addition step.

Online sexual activities in Hispanic women: A chance for non-heterosexual women?

2020

Abstract:  Sexuality is still modulated by social determinants that promote a passive role for women. In the recent decades, some findings have supported the influence of the Internet on sexuality. However, the relevance of online sexual activities for some groups such as Hispanic young women is still unknown. In this context, this study examines online sexual experience among 310 Hispanic women from Argentina, Mexico and Spain; as well as the role of their offline sexuality and country in this sexual pattern. As a result, Hispanic women report a variety of online sexual activities that ranges from searching information to masturbation. In particular, the Internet use for sexual purposes is…

Fiber Suspension Flows: Simulations and Existence Results

2016

Main result of this article is demonstrating the weak global in time well posedness result for the equations governing fiber suspension flows for sufficiently small initial data under mild assumptions about the nonlinear equation for fiber orientation dynamics and the constitutive law, thus extending the previous local in time results. The required estimate of growth of the H 2 norm is granted if the L ∞ norm of fiber orientation state variables remains bounded. This is the case for fiber orientation tensors.

Dynamics of supercooled liquids and glassy solids

2001

Recent developments in the evaluation of Mössbauer line intensities

1985

The angular dependence of the intensities of pure or mixed multipole transitions is formulated in a new fashion, which takes into account arbitrary texture of the Mossbauer absorber ranging from complete orientation (single crystals) over preferred orientation to random powders and an anisotropic absorption fraction of the nuclei. The application of the theory is demonstrated by means of typical examples from the literature.

Nuclear moments from laser spectroscopy

1988

The systematic laser spectroscopy measurements of nuclear spins, moments and charge radii from hyperfine structures and isotope shifts are reviewed from a methodical point of view. Examples are given for the typical experimental approaches and their results. Laser spectroscopy methods of direct nuclear g-factor measurement have interesting features in common with the low-temperature nuclear orientation technique. These are described in some detail and discussed in their particular physics context.

The orientational glass studied by nuclear magnetic resonance

1997

Single crystals of the orientational glass have been studied using iodine NMR for temperatures 1.8 K < T < 300 K. Two-dimensional spectroscopy has shown that the quadrupole-perturbed central transitions are predominantly inhomogeneously broadened. The orientational glass transition is already accompanied by a considerable increase of that broadening in the regime of fast motion. Evidence for a random-field smearing of the random-bond-induced freezing process is obtained. Measurements of the spin - lattice relaxation time reveal the existence of a broad distribution of orientational correlation times at low temperatures.

Older rehabilitees’ life-course agency in Finnish gerontological rehabilitation

2015

Aims: This study investigates gerontological rehabilitation sessions of Finnish rehabilitees in the framework of life-course agency from the perspectives of temporal orientation and agency. Methods: The research data were obtained by non-participatory observation in 11 individual goal-setting sessions between 11 rehabilitees and their personal counsellors. The data were analysed in accordance with data-driven, qualitative content and narrative analysis, with an emphasis on the life-course agency approach. Results: Four temporal orientations of older rehabilitees were identified in the rehabilitation sessions: (i) timeless, (ii) past, (iii) present, and (iv) life course. For each temporal or…