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India has been accustomed to following Western educational psychology theories; the author suggests that Russian theories are more compatible with India's present situation, and gives examples. (SP)

An efficient semimicro gravimetric method for the determination of mercury(II) and zinc(II) is presented. Potassium thiocarbonate (PTC) has been used as a source of sulfide and thiocarbonate ions affording clean precipitation from homogeneous solution and allowing the direct weighing of the precipitate when dry. The use of EDTA, ammonium tartrate, and PTC for masking of adverse ions in alkaline medium has afforded an efficient analytical separation of Hg(II) and Zn(II). The mean relative error is less than 1% in these estimations.

An efficient and speedy method for the estimation of ruthenium (III), rhodium (III), palladium (II), osmium (VIII), iridium(III) and platinum(IV) is described by using ring colorimetry with potassium thiocarbonate (PTC). Binary mixtures show the following limits when present in 1.5μl of solution, Ru(III) 0.49μg; Rh(III) 0.43μg; Pd(II) 0.38μg; Os(VIII) 0.71μg; Ir(III) 0.53μg; Pt(IV) 0.38μg; present singly the limits are 0.20—0.30μg.

Changes in transthoracic electrical impedance (T.E.I.) due to high-altitude hypoxia (3,658 m) have been measured in 20 young, healthy Indian soldiers. They were first studied at sea level (198 m) and then rapidly transported by air to 3,658 m, where they were studied daily from day 1 to day 5 and then on days 8 and 10. The mean (+/-S.D.) T.E.I. at sea level (34.6+/-0.6Omega) fell sharply to 29.6+/-0.8Omega, 30.3+/-0.9Omega, and 30.5+/-1.1Omega on days 1, 2, and 3 (P0.001) and levelled off at 31.5+/-0.7Omega on day 10, which was comparable to the mean value obtained in 13 persons permanently resident at high altitude (32.2+/-0.7Omega). Five sea-level residents who had acute mountain sickness (A.M.S.) or high-altitude pulmonary oedema (H.A.P.O.) had a still lower mean value (22.5+/-1.1Omega). One normal healthy subject who at sea level had a T.E.I. of 34.7Omega developed H.A.P.O. when the T.E.I. fell to 21.1Omega. Ninety minutes after the administration of 80 mg of intravenous frusemide the value increased to 35.5Omega. In another subject with A.M.S. who received 40 mg of frusemide intravenously the T.E.I. rose from 21.9 to 33.2Omega.Since the study was non-invasive the changes in impedance could not be correlated objectively with alterations in either pulmonary blood volume or pulmonary extravascular water space. In the subject, however, with x-ray evidence of H.A.P.O. and a low T.E.I. intravenous frusemide produced a marked rise in T.E.I. together with clearing of the chest x-ray picture within 24 hours, indicating an inverse relationship between impedance and thoracic fluid volume. It is suggested that with further objective verification in man the measurement of T.E.I. may be a potentially promising technique for the early detection of increased pulmonary fluid volume.

Investigations into the vertical distribution of stream animals by means of a coring technique have demonstrated that they could be found many decimeters down in the gravel; a maximum of 17% was found in the top 5 cm.Sampling of arctic streams revealed that chironomid larvae comprised 70–80% of the numbers in the benthos and that their rate of drift did not vary with the time of day.Life history studies of stream invertebrates have demonstrated clear seasonal patterns in Canada. Work has been done on several mayflies and stone flies, some Chironomidae, and two species of Gammarus. Currently the life histories of the stone flies of southern Australia are being investigated in which the seasonality is much less marked.After the experimental application of the blackfly larvicide Methoxychlor to two rivers, a catastrophic drift of invertebrates occurred and larvicide residues were detected up to 8 wk after application.Work on the decomposition of autumn-shed leaves in water has included the responses to temperature and to additional nutrients (N and P). The effect of nutrient addition was to increase the amount of nitrogen in the leaf after incubation, but temperature affected only the rate of decomposition. Determination of the relative importance of bacteria and fungi in decomposition, was studied with use of antibiotics, and food preference of Gammarus for several leaf species was determined.A considerable portion (up to 40%) of the autumn-shed leaf is water-soluble, and the way in which it is made available to stream animals was investigated. One process, its conversion into particles, appears to involve mechanisms similar to those found in soils, i.e. by formation of organic/metal complexes. Using infrared spectroscopy, attempts have been made to characterize the laboratory and field-produced particles. Field investigations have also demonstrated large-scale fluctuations, during only a few hours, of dissolved and particulate organic matter in the water.These findings are considered in relation to general stream ecology.

The free carrier nonlinear dielectric constant of a degenerate electron-hole plasma (e.g., Ge) in the presence of a Gaussian electromagnetic beam has been studied by a kinetic treatment. The redistribution of carriers (electrons and holes) is the source of nonlinearity and is effective in causing the self-focusing of the beam. The rise in carrier temperature due to the wave field is almost unaffected by the degeneracy, whereas the nonlinearity is considerably affected by it. The increase of degeneracy (by increasing the equilibrium carrier concentration at the fixed lattice temperature) increases the nonlinear dielectric constant. Hence self-focusing is enhanced by degeneracy.

The hot carrier effects and d.c. conductivity of a semi-metal (e.g. Bismuth) have been studied by using the semi-kinetic treatment and the effective temperature model. The isotropic part of carrier distribution function is taken to be Fermi-Dirac in each valley correspponding to different effective temperatures which are determined by solving the energy balance equation. The anisotropy of the electron and hole mass has been incorporated and the carriers relaxation time is assumed to be isotropic. The anisotropy of the conductivity is studied by orienting the d.c. electric field along the three crystallographic axes. It is concluded that the hot carrier (i.e. non-linear) effects can be observed in semi-metals also because of their comparatively low conductivity.