Reaction Time of a Group of Physics Students

The reaction time of a group of students majoring in Physics is reported here. Strong co-relation between fatigue, reaction time and performance have been seen and may be useful for academicians and administrators responsible of working out time-tables, course structures, students counsellings etc.Comment: 10 pages, 4 figure

Photogenerated Carriers in SrTiO3 Probed by Mid-Infrared Absorption

Infrared absorption spectra of SrTiO$_3$ have been measured under above-band-gap photoexcitations to study the properties of photogenerated carriers, which should play important roles in previously reported photoinduced phenomena in SrTiO$_3$. A broad absorption band appears over the entire mid-infrared region under photoexcitation. Detailed energy, temperature, and excitation power dependences of the photoinduced absorption are reported. This photo-induced absorption is attributed to the intragap excitations of the photogenerated carriers. The data show the existence of a high density of in-gap states for the photocarriers, which extends over a wide energy range starting from the conduction and valence band edges.Comment: 5 pages, 5 figures, submitted to J. Phys. Soc. Jp

The velocities induced by distributions of infinite kinked source and vortex lines representing wings with sweep and dihedral in incompressible flow

Equations have been derived for the velocities induced in an incompressible flow by distributions of infinite source and vortex lines representing wings of infinite span and constant chord having both sweep and dihedral. Particular attention is paid to the centre section where the dihedral effects are large. The equations showed that such a source distribution does not represent a wing with symmetrical sections, and that such a vortex distribution does not represent a thin wing. It is, therefore, not possible to separate the effects of wing thickness and wing load distribution, even when linear-theory assumptions are retained. This work was done before the widespread use of electronic computers to calculate wing characteristics. It is published now to illustrate the complex nature of the equations for the velocities induced by nonplanar singularity distributions

Pressure and boundary-layer measurements on a two-dimensional wing at low speed

Results are given of pressure measurements and boundary-layer traverses on a two-dimensional wing with 10 per cent RAE 101 section at Reynolds numbers of 1.6 x 10power6 and 3.2 x 10power6. These results, which have been integrated to give lift, drag and aerodynamic-centre characteristics, are used to check some calculation methods for the growth of the turbulent boundary layer and for the effect of a known boundary layer on the pressure distribution. It is concluded that the calculation of the boundary layer still needs a little refinement before it is accurate enough to predict viscosity effects on pressure distribution, lift, drag and aerodynamic centre; but that these effects can be calculated if the actual boundary-layer characteristics are known

The calculation of the spanwise loading of sweptback wings with flaps or all-moving tips at subsonic speeds

The results of some electric tank tests by Duquenne and Grandjean on wings of 45 deg sweepback with trailing edge flaps have been analysed to provide the basis for a method of calculating the spanwise loading. The analysis yielded information about the effect of sweep on the equivalent incidence of a section with flap, on the downwash factor and on the spanwise loading distribution with an incidence discontinuity. Interpolation formulae are developed to extend the results to wings of any sweep and flap span, and thus a complete calculation method is presented for the spanwise loading with this type of control. The calculation method is tentatively extended to a wing with all-moving tip control, and the results compared with those of Thomas and Mangler. There is a marked discrepancy between the two calculations. Further electric tank tests to fill this, and other gaps are suggested

Happiness matters : exploring the linkages between personality, personal happiness, and work-related psychological health among priests and sisters in Italy

This study responds to the challenge posed by Rossetti’s work to explore the antecedents and consequences of individual differences in happiness among priests and religious sisters. The Oxford Happiness Questionnaire was completed together with measures of personality and work-related psychological health by 95 priests and 61 religious sisters. Overall the data demonstrated high levels of personal happiness among priests and religious sisters, but also significant signs of vulnerability. Personality provided significant prediction of individual differences in both personal happiness and work-related psychological health. However, personal happiness provided additional protection against work-related emotional exhaustion and additional enhancement of work-related satisfaction. These findings suggest that acknowledging and affirming personal happiness may enhance the work-related psychological health of Catholic priests and religious sisters

The emergence of a stable neuronal ensemble from a wider pool of activated neurons in the dorsal medial prefrontal cortex during appetitive learning in mice

Animals selectively respond to environmental cues associated with food reward to optimize nutrient intake. Such appetitive CS-US associations are thought to be encoded in select, stable neuronal populations or neuronal ensembles, which undergo physiological modifications during appetitive conditioning. These ensembles in the medial prefrontal cortex (mPFC) control well-established, cue-evoked food seeking, but the mechanisms involved in the genesis of these ensembles are unclear. Here, we utilized male Fos-GFP mice that express the green fluorescent protein (GFP) in recently behaviorally-activated neurons, to reveal how dorsal mPFC neurons are recruited and modified to encode CS-US memory representations using an appetitive conditioning task. In the initial conditioning session, animals did not exhibit discriminated, cue-selective food seeking, but did so in later sessions indicating that a CS-US association was established. Using microprism-based in vivo 2-Photon imaging, we revealed that only a minority of neurons activated during the initial session was consistently activated throughout subsequent conditioning sessions and during cue-evoked memory recall. Notably, using ex vivo electrophysiology we found that neurons activated following the initial session exhibited transient hyper-excitability. Chemogenetically enhancing the excitability of these neurons throughout subsequent conditioning sessions interfered with the development of reliable cue-selective food seeking, indicated by persistent, non-discriminated performance. We demonstrate how appetitive learning consistently activates a subset of neurons to form a stable neuronal ensemble during the formation of a CS-US association. This ensemble may arise from a pool of hyper-excitable neurons activated during the initial conditioning session

The OH Masers Towards IRAS 19092+0841

Context. Maser emission is a strong tool for studying high mass star forming regions and their evolutionary stages. OH masers in particular can trace the circumstellar material around protostars and determine their magnetic field strengths at milliarcsecond resolution. Aims. Imaging OH maser mission towards high mass protostellar objects to determine their evolutionary stages and to locate the detected maser emission in the process of high mass star formation. Methods. In 2007, we surveyed OH maser towards 217 high mass protostellar objects to study its presence. In this paper, we present a follow up MERLIN observations of a ground state OH maser emission towards one of these objects, IRAS 19092+0841. Results. Emission from the two OH main spectral lines, 1665 and 1667 MHz, were detected close to the central object. The positions and velocities of the OH maser features have been determined. The masers are distributed over a region of ~ 500 corresponding to 22400 AU (or ~ 0.1 pc) at a distance of 4.48 kpc. The polarization properties of the OH maser features were determined as well. We identify three Zeeman pairs from which we inferred a magnetic field strength of ~ 4:4mG pointing towards the observer. Conclusions. The relatively small velocity spread and the relatively wide spacial distribution of the OH maser features support the suggestion that this object could be in an early evolutionary state before the presence of disk and/or jet/outfows.Comment: 6 pages, 2 figures and 3 table