Optical data processing using paraboloidal mirror segments

An optical data processing system using paraboloidal reflecting surfaces is disclosed. In the preferred embodiment the paraboloidal reflecting surfaces are segments of a paraboloidal mirror. A source of coherent light is in the focal plane of the first paraboloidal mirror segment which collimates the beam and reflects it toward a second paraboloidal mirror surface. The information to be analyzed, on a transparency for example, is placed in the collimated beam. The beam is reflected from the second paraboloidal mirror segment and focused on a Fourier transform plane. A photon detector could be placed in the Fourier transform plane or suitable spatial filters, with the filtered beam then being reflected from a third paraboloidal mirror segment to be focused on a reconstruction plane

Field and photon enhanced electron emission characteristics of cadmium sulphide field emitters

Field and photon enhanced electron emission characteristics of cadmium sulfide field emitter

fMRI Randomized Study of Mental and Motor Task Performance and Cortisol Levels to Potentiate Cortisol as a New Diagnostic Biomarker.

Cortisol is an important hormone in the protective stress response system, the Hypothalamus-Pituitary-Adrenal (HPA axis). It becomes especially salient in immune suppression syndromes such as multiple sclerosis and Cushing’s disease. Fatigue is a common symptom and mental and motor tasks are difficult and labored. The role of cortisol is mental and motor tasks and the recruitment of key brain regions in completion of these tasks is explored together with functional magnetic resonance imaging in healthy participants. Cortisol levels were found to be higher and had greater reduction in levels during mental versus motor tasks. Recruitment of brain stem and hypothalamus regions, important in cortisol activity, was affected differently. At low cortisol levels, mental task participants had less activity in the regions than their physical task counterparts. When cortisol levels were higher, widerspread recruitment of these brain regions was seen in the mental task participants, and for the physical task participants, the spread was at comparative low levels of cortisol. It is concluded that cortisol is implicated in these brain regions supporting the Thompson Cortisol Hypothesis and that brain region recruitment is likely to be dependent upon factors including cortisol levels as well as perception of stress in the task. It is suggested that mental tasks are perceived more stressful than physical but demand higher cortisol levels to promote wider spread brain region activity. Implication for neurological disease includes the use of cortisol in the proposed development of a potential new diagnostic biomarker for early detection of neurological sequelae

Proceedings of the Second workshop on scientific results of FORV Sagar Sampada

Since inception in 1984, the Fisheries and Oceanographic Research Vessel Sagar Sampada, with sophisticated modern facilities onboard, has undertaken more than 140 cruises all over the Indian Ocean primarily in our Exclusive Economic Zone for fishery and oceanographic survey. Scientists from many institutions have made use of this facility to explore the resource potential in our sea and to understand its correlation with the environmental parameters. These survey and exploration efforts are continuing. This volume contains many papers which are the outcome of research work carried out onboard 'Sagar Sampada' during last five years (1989-1993) and presented in a Workshop to evaluate the scientific work. About 60 papers, included in this volume, bring out the results pertaining to environmental assessment, hydrology, productivity estimates, fishery resources availability, fishing technology, pollution monitoring etc. These relate mainly to the Arabian Sea, Bay of Bengal and Lakshadweep, Andaman and Nicobar Islands groups in the EEZ of India. These efforts along with other mission-oriented cruises have yielded valuable information on the fishery resources and their distribution in space and time

Prevalence of behavioural and psychological problems in working children

OBJECTIVE: To determine the prevalence and screen the nature and types of behavioural and psychological problems among working children in Karachi. METHODS: A cross sectional study was conducted in three urban squatter settlements of Karachi from May to June 2006, targeting working children aged 11-16 years. Behavioural Problems of these children were estimated by using the self reported Urdu version of the Strengths and Difficulty Questionnaire. The results were cross-tabulated using SPSS 13.0 with the identified risk-factors. RESULTS: Out of a total of 225 respondents, 94.2% (n = 212) males and 5.8% (n = 13) females, the prevalence of Behavioural Problems among working children was found to be 9.8%. Peer problems were most prevalent (16.9%) seconded by Conduct problems (16.7%). Adverse family environment and work environment were closely associated with Behavioural Problems in these children. CONCLUSION: Our study reinforces the need for measures to improve the environment of the children and prevent the psychological and behavioural problems associated with working children. Gradual, long-term policies are required to decrease the need for working children, though sudden abolishment would cause more detrimental effects

Interaction of vortices in viscous planar flows

We consider the inviscid limit for the two-dimensional incompressible Navier-Stokes equation in the particular case where the initial flow is a finite collection of point vortices. We suppose that the initial positions and the circulations of the vortices do not depend on the viscosity parameter \nu, and we choose a time T > 0 such that the Helmholtz-Kirchhoff point vortex system is well-posed on the interval [0,T]. Under these assumptions, we prove that the solution of the Navier-Stokes equation converges, as \nu -> 0, to a superposition of Lamb-Oseen vortices whose centers evolve according to a viscous regularization of the point vortex system. Convergence holds uniformly in time, in a strong topology which allows to give an accurate description of the asymptotic profile of each individual vortex. In particular, we compute to leading order the deformations of the vortices due to mutual interactions. This allows to estimate the self-interactions, which play an important role in the convergence proof.Comment: 39 pages, 1 figur

Measurement of W± boson production in Pb+Pb collisions at √sNN=5.02Te with the ATLAS detector

A measurement of W± boson production in Pb+Pb collisions at sNN=5.02Te is reported using data recorded by the ATLAS experiment at the LHC in 2015, corresponding to a total integrated luminosity of 0.49nb-1. The W± bosons are reconstructed in the electron or muon leptonic decay channels. Production yields of leptonically decaying W± bosons, normalised by the total number of minimum-bias events and the nuclear thickness function, are measured within a fiducial region defined by the detector acceptance and the main kinematic requirements. These normalised yields are measured separately for W+ and W- bosons, and are presented as a function of the absolute value of pseudorapidity of the charged lepton and of the collision centrality. The lepton charge asymmetry is also measured as a function of the absolute value of lepton pseudorapidity. In addition, nuclear modification factors are calculated using the W± boson production cross-sections measured in pp collisions. The results are compared with predictions based on next-to-leading-order calculations with CT14 parton distribution functions as well as with predictions obtained with the EPPS16 and nCTEQ15 nuclear parton distribution functions. No dependence of normalised production yields on centrality and a good agreement with predictions are observed for mid-central and central collisions. For peripheral collisions, the data agree with predictions within 1.7 (0.9) standard deviations for W- (W+) bosons