Mother mouse sets the circadian clock of pups

We report here the ontogeny of a circadian clock of the field mouseMus booduga expressing itself 16 days after parturition in the locomotory activity of neonate pups removed from the mother and held in continuous darkness ever since birth. Locomotion is a 'complex' activity serving such functions as foraging, exploration, and territoriality. Since these functions are not conventionally associated with neonate and altricial animals, it is of interest that this ability has such an early circadian origin. A backward extrapolation of the pups rhythm and the rhythm of the mother strongly implicate maternal synchronization. The period of the circadian rhythm of the pups shortens with age, from birth up to six months

Continuous light abolishes the maternal entrainment of the circadian activity rhythm of the pups in the field mouse

12:12-h cycles of presence and absence of mother mouse act as a 'zeitgeber' and entrain the circadian rhythm of locomotor activity in the pups ofMus booduga under continuous darkness or continuous dim light. Continuous higher illumination of 15-25 lx abolishes this impressive maternal entrainment

Spin-Hall effect and circular birefringence of a uniaxial crystal plate

The linear birefringence of uniaxial crystal plates is known since the 17th century, and it is widely used in numerous optical setups and devices. Here we demonstrate, both theoretically and experimentally, a fine lateral circular birefringence of such crystal plates. This effect is a novel example of the spin-Hall effect of light, i.e., a transverse spin-dependent shift of the paraxial light beam transmitted through the plate. The well-known linear birefringence and the new circular birefringence form an interesting analogy with the Goos-H\"anchen and Imbert-Fedorov beam shifts that appear in the light reflection at a dielectric interface. We report the experimental observation of the effect in a remarkably simple system of a tilted half-wave plate and polarizers using polarimetric and quantum-weak-measurement techniques for the beam-shift measurements. In view of great recent interest in spin-orbit interaction phenomena, our results could find applications in modern polarization optics and nano-photonics.Comment: 16 pages, 8 figures, to appear in Optic

Ultra Wideband Channel Characterization and Ranging in Data Centers

This paper presents a detailed measurement based characterization of the Ultra Wideband (UWB) channels in a data center environment and examines the accuracy of direct ranging using Time of Arrival (ToA) measurements. Modern data centers present a unique indoor environment that to our knowledge has not yet been characterized. Our ranging experiments indicate that it is possible to achieve an accuracy of fraction of a meter via direct ranging and point to the feasibility of locating individual servers using more sophisticated cooperative ranging

Kinetics of Decomposition of Nitramine Propellant by Differential Scanning Calorimetry

The paper describes an experimental procedure for the determination of overall kinetic parameters for the exothermic decomposition reaction of nitramine propellant. The kinetic parameters can be obtained through the use of differential thermal analysis (DTA), differential scanning calorimetry (DSC) or thermogravimetric analysis (TGA) methods. The procedure is applicable to reactions whose behaviour can be described by the Arrhenius equation and the general rate law. In the present work, DSC technique has been used for the evaluation of Arrehenius activation parameters and specific rate constants for thermal decomposition of a typical nitramine propellant. The kinetic parameters were computed by Ozawa and Kissinger methods for comparison. The activation energy value obtained from the Ozawa method is refined by an iteration procedure using Doyle approximation for the Arrhenius temperature integral p(x)

Fry of the milk-fish Chanos chanos (Forskal)

It is well known that the fry of the milkfish Chanos chanos; (Forskal), appear in large numbers In the tidal flats of the Pamban area, especially near the Chinnapalam creek. Observations of Delsman (1929), in the indonesian waters have shown that the fish larvae appeal first in the summer months of April and May, and later in the months of September, October and November

Some aspects of adaptation in Chanos chanos (Forskal)

The possibilities of culturing marine species of fishes in coastal belts containing salt or fresh-water have received much attention in recent years, following the lead given by Far Eastern countries in the culture of Chanos. In India, Chanos as well as species of mullets could be cultured on a large scale and a beginning in this direction has already been made in certain South Indian • centres. A study of the mechanism of adaptation in these species is an essential prerequisite to any rational system of culture, since it will help in determining the optimal values of salinity and temperature of the environment for the various species

Effect of Hypocaloric Stress on Body and Tissue Composition of Rats K

Rats fed ad libitum, a ration comprising fresh foods (F ration) for 10 days, were switched over to another ration consisting of processed foods (P ration) for a similar period. Thereafter, the animals were subjected to a 50 per cent diet restriction for a period of 10 days and rehabilitated either on F ration or P ration for an equal period. The results showed a decline in growth rate, food consumption and food efficiency ratio in the group fed ad libitum on P ration compared to that on F ration. Fifty per cent diet, restriction induced loss of body weight due to depletion of body fat. A fall in the gross weight of liver,kidney and epididymal fat pad along with a reduction in the contentsof lipid in liver and fat pad were also observed. Refeeding ofdiet-restricted rats induced hyperphagia and super-normal weight gainwith both rations. The data on liver triglycerides appeared to show anage-related rise which could be controlled by diet restriction to someextent. Feeding of P ration tended to predisperse to higher adiposetissue cholesterol attributable to higher fat content of this ration

Free vibration of angle-ply laminated conical shell frusta with linear and exponential thickness variations

Free vibration of laminated conical shell frusta of variable thickness is studied using spline approximation. This problem includes first order shear deformation and considers shells as antisymmetric angle-ply orientation. The governing differential equations of the shells are resolved in terms of displacement functions and rotational functions. These functions are approximated using splines and the method of collocation is adopted for simultaneous algebraic equations. These equations become generalized eigenvalue problems and are solved numerically to avail eigenfrequencies and the corresponding eigenvectors. The variation of frequencies is analysed with respect to the cone angle, aspect ratio, material properties, number of layers, and thickness variation