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The results from stratigraphy, radiocarbon dating and pollen analysis of three salt-lake deposits at Sambhar, Lunkaransar and Didwana in western Raj'asthan, and one freshwater lake deposit at Pushkar in the Aravalli Hills, are described in conjunction with pollen analysis of some archaeological soil samples from the Indus Valley site at Kalibangan in northern Rajasthan. The salt-lake deposits studied are stratigraphically divisible into (a) pre-lacustrine, (b) lacustrine and (c) post-lacustrine sections. The pre-lacustrine section is characterized by a thick bed of aeolian sand underlying lacustrine sediments, while the lacustrine and post-lacustrine sections are broadly circumscribed by laminated clay and nonlaminated silt respectively. The pollen record from the four lake profiles studied is divided into local pollen zones. Four regional pollen assemblage zones are delineated for the area west of the Aravalli Range in Rajasthan. The environmental history deduced from the pollen record is divisible into phases I-V, of which phases II-V follow the regional pollen assemblage zones. Phase I is stratigraphically determined, and is representative of severe arid environments under which the sand dunes, now stabilized, are suggested to have been active. The plant microfossils first appear in phase II with the deposition of lacustrine sediments dated to around 10000 b . p . The vegetation comprises an openland steppe which is rich in grasses, Artemisia and sedges and poor in halophytes. Artemisa, Typha angustata, Mimosa rubicaulis and Oldenlandia , which now grow under areas of comparatively higher average annual rainfall (above 50 cm), appear to have flourished in the semi-arid belt, while the first two plant taxa had encroached even as far as the arid belt, both suggesting that a general westward shift of the rainfall belts had taken place. Vegetation destruction through burning by man is suggested to have started together with the first occurrence of Cerealia-type pollen at about 7500 b . c . and continued thereafter throughout phases III and IV. The increase in swamp vegetation and the intensification of vegetation cover inland together with the maxima of all mesophytic elements in phase IV ( ca. 3000 b .c . to ca. 1000 b .c .) indicate an increase in the rainfall, apart from a short relatively drier time about 1800-1500 b . c . at Sambhar which correlates with the decline of the Indus culture in northwest India. Phase IV is immediately followed by aridity for which there is stratigraphic evidence that the salt lakes started drying. At Pushkar, there is evidence that the vegetation showed a marked change in the Aravallis. The onset of this aridity is suggested to have been widespread. The climate did not ameliorate until about phase V (? early centuries a .d . to present) at which time the Rangmahal culture perhaps flourished in Rajasthan, the remains of which imply good water supply. In conclusion it is suggested that the Rajasthan desert is primarily natural, its history punctuated by at least one more vegetated, humid period during the Holocene, the climatic control of which as indicated by the vegetation history is consistent with climatic events elsewhere in the world.

Thermoluminescence (TL) glow curves of gamma-irradiated SrCl2 doped with Eu, Gd, Tb and Am in trivalent form have been obtained in the temperature ranges 77-300K and 300-600K. The glow peaks in the lower temperature range are accounted for by the successive bleaching of Vk-type trapped hole centres. Electron paramagnetic resonance (EPR) studies of Eu-doped samples in the temperature range 300-500K have been carried out in detail and the results strongly suggest that the TL glow peak around 500K is followed by the trapping of an electron by Eu3+ and the TL glow around 420K is due to the thermal destruction of OH0 centres. The TL glow curves have been analysed to obtain the trap depth and frequency factors.

An emission spectrographic method for the estimation of traces of some common impurites viz., Al, Ba, Bi, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sn, Ti and V in high-purity sulphur is described. The impurities separated from 1-g sample, after removing sulphur as SO2 by heating it in air at about 300° C, were dissolved in a small amount of 6M hydrochloric acid and loaded on 10 mg of carrier mixture containing 90% graphite and 10% sodium chloride in the 1/4″ electrode crater. The spectra were exited in a D. C. arc carrying 13 A current for 45 seconds. Cobalt was used as an internal standard and sodium chloride as a carrier. The lowest detection limits lie in the range 0.005 to 0.05 ppm for the different elements. The precision of the method ranges from 6–19% for the elements analysed.

Combined free and forced convection heat transfer from a horizontal circular cylinder to a transverse flow is analysed for the case when the forced flow is either in the direction of the free convection flow (parallel flow) or in the direction opposite to it (counter flow). The problem is solved for two cases: (1) a specified surface temperature variation and (2) a specified wall heat flux variation along the circumference. A coordinate perturbation method is used to transform the governing set of partial differential equations into a system of ordinary differential equations, which are solved by numerical methods. The numerical work is done for the boundary conditions of constant surface temperature and constant wall heat flux. The variation of local heat transfer coefficient and wall shear stress along the circumference up to the point of separation and velocity and temperature profiles in the boundary layer are obtained for varying values of the governing parameters Gr/Re2 in the constant temperature case (or Gr/Re2 in the constant heat flux case) and Pr.

Two-center one-electron integrals needed in certain molecular correlated wave function calculations, using one-center expansion approximation, have been studied. The form of the basic correlated function used in this study is The parent integral is expressed in terms of an angular integral, and an auxiliary radial integral depending upon the variables r1, r2, and r12. Several analytical formulas, and a recursive formula are derived for the auxiliary integral, and other related integrals. All these formulas are given in computationally useful forms. Logical flow charts and FORTRAN programs were constructed for computing the basic integrals discussed in the paper. Numerical values of some integrals, thus obtained, are tabulated for comparisons.

An emission spectrographic method is described for the determination of certain rare earths—Ce, Sm, Eu, Gd, Dy, Ho, Er, Yb, and Lu—at fractions of ppm concentration in uranium samples using LiF-AgCl-graphite powder mixture as carrier. The rare earths chemically separated from uranium were excited in a dc arc. Thulium was used as an internal standard. The detection limits in ppm on the basis of 5 g uranium sample are: Yb 0.004; Eu, Gd, Er 0.02; Dy, Lu 0.05; Sm, Ho, 0.2; and Ce 0.5. The precision of the method expressed as a coefficient of variation is estimated to be ±9%. The effect of 14 nonrare earth elements on the intensity of analysis lines was investigated.

One‐center‐expansion, self‐consistent‐field calculations are carried out for BeH3−, BH3, CH3+, NH3++, and OH33+ systems. Using a limited basis set, all of these molecules are found to be planar (θZAH=90°), except the OH33+ system which is found to be unstable. The extended‐basis‐set calculations are carried out only for BeH3−, BH3, CH3+, and NH3++. These calculations give the internuclear distances to be 2.500, 2.191, 2.032 and 2.074 bohrs, respectively, the total energies −16.144047, −26.235841, −39.117795, and −54.980821 hartrees, respectively, and the first ionization potential (—e1e′) 0.1402, 0.4802, 0.9293, and 1.4329 hartrees, respectively. Estimated values of the Hartree—Fock energy and the total nonrelativistic energy are also given for these four molecules.

One‐center self‐consistent‐field calculations have been carried out for the H3+ molecule using symmetry‐adapted Slater‐type basis functions centered at the center of the molecule. The best computed values of the distance of a hydrogen from the center of H3+ triangle, ROH(H3)+, and the total energy (E) are 0.937 bohr and −1.2863 hartree, respectively. It is estimated that the present result differs from the Hartree—Fock result by about 0.023 hartree in (0.63 eV) E. The orbital density of the 1a1′ orbital is plotted as a function of ROH(H3+) for various basis sets used, and the results are discussed.

Single‐determinant self‐consistent field wavefunctions calculated by the one‐center expansion method are reported for the NH3 and NH molecules. The molecular orbitals were expanded in terms of symmetry adapted Slater‐type orbitals centered at the heavy nucleus. To obtain the potential‐energy curve for the NH3 molecule corresponding to the tunneling motion of the N atom through the H3 plane, the calculations were carried out for twelve different geometrical configurations. In the present work only those geometrical configurations of NH3 are considered for which all three N–H distances are the same, and are denoted by RNH(NH3). For each geometrical configuration of NH3, defined by a fixed value of the bond angle (or the apex angle), the optimum values of RNH(NH3) and basis function exponents were determined. For the NH molecule, the calculations were carried out at seven different internuclear distances, RNH. At each RNH, the best basis function exponents were determined. These seven points were used to con...

A virus disease of tree tomato due to a strain of potato virus Y is described. The results are based on host range, physical properties and serology. It is suggested that tree tomato may be one of the harboring hosts of potato virus Y found prevalent in the potato crop.

An emission spectrographic method for the estimation of impurities of Al, As, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Mo, Ni, Pb, Sb, Sn, Te, Ti, V, Zn and Zr in high purity selenium at concentrations less than 1 ppm has been developed. The impurities were separated from 1 g of selenium by volatilizing Se from its solution in nitric acid and sulphuric acid. The residue containing impurities was dissolved in small amounts of 6 M HCl and loaded along with the washing on 10 mg mixture containing graphite (90%) and sodium chloride carrier (10%), in the electrode crater. The spectra were excited in a d.c. arc carrying 13 A. The detection limits lie in the range 0.005–0.5 ppm for the different elements. The precision of the method ranges from 7–18% for these elements.

This paper examines the conditions on the coefficient matrix of the linear model under which contrasts, and contrasts alone, are estimated by contrasts.

SUMMARYTwo experiments were made with dairy cows in 1969 and 1970 to compare two grazing systems. Treatment A was a rigid rotational system and B was a system in which cows always grazed on an area which had been cut 4 weeks earlier for conservation. For both treatments the stocking rate was 6·2 cow/ha and fertilizer N was applied at a rate equivalent to 2·5 kg/ha per day.Individual records of milk yield, milk composition and live weight were kept, the quality of herbage available was estimated weekly, and individual intakes were estimated by faecal index methods at approxi- mately monthly intervals. In 1969 the cows remained on the same treatment throughout the season and in 1970 a reversal design was adopted.The quantities and quality of herbage available per cow were generally similar under both treatments. There were no significant differences in feed intake, or animal production between the treatments. High yields of 11900 kg milk and 28 000 Meal ME per hectare were recorded.

Single‐determinant self‐consistent‐field wavefunctions calculated by the one‐center expansion method are reported for CH3− and OH3+ molecules. The basis functions, symmetry adapted Slater‐type orbitals, were all centered at the heavy nucleus. In both cases a total of 25 basis functions were used. Both of these molecules were found to be nonplanar. For CH3−, the equilibrium bond length and bond angle were found to be 2.028 bohr and 109°56′, respectively; for OH3−, these quantities were calculated to be 1.918 bohr and 110°54′. The total energy of these molecules was found to be−39.3367 hartree for CH3−, and −76.2330 hartree for OH3+. A limited basis‐set calculation for planar OH3+ using 17 symmetry adapted STO's is also reported. The total energy and bond length for this case are −76.1704 hartree, and 1.826 bohr, respectively. Some other interesting features of these calculations are discussed.

Bildungskonstanten der l : 1:1-Ni(II)-Komplexe mit o-Phenanthrolin und Brenzcatechin, Protocatechw, Thioglykol- oder Thioapfelsaure werden unter Anwendung einer modifizierten Irving-Rossotti-Titrationstechnik bestimmt.

Untersuchungen uber das Verhalten des Blutzuckers nach langerem Nahrungsentzug bei Fischen.

Effect of one day fermented milk (butter milk) was studied in 18 medical students between 18 to 20 years of age. Results showed that there is a significant decrease in fibrinolytic activity two hours after giving butter milk and the effect persists even at the end of six hours.

Chemistry Department, M. S. University of Baroda, Baroda-2 Manuscript received 16 November 1972; revised 14 March 1973; accepted 30 May 1973 Fomation constants,\(K_{Ni.Hist.L}^{Ni.Hist}\)where L =hydroxy or mercapto acid,\(K_{Ni.NTA.L}^{Ni.NTA}\)where L = mer-capto acid and\(K_{Cu.NTA.L}^{Cu.NTA}\)where L=hydroxy acid, have been determined by using the modifiedmethod of lrving-Rossotti titration technique. Both hydroxy and thioacids behave alike as secondary ligands. It has been inferred that the contribution of \(\pi\) interaction in stabilizing M-S bond in complexse is not very significant.

The properties and kinetics of purified brain hexokinase (E.G. 2.7.1.1), which was obtained in soluble form by elastase treatment, were studied. The enzyme was found to be 90% pure by ultracentrifugation. It was stable in 1 m glucose or sucrose containing phosphate and thioethanol. Its activity was unchanged between pH 5.5 and 8. The Km values for ATP, Mg2+, glucose, mannose, and fructose were 0.5, 2.8, 0.038, 0.03 and 1.5 m m , respectively. Inhibition by glucose 6-phosphate (P) and reversal of the inhibition by inorganic phosphate (Pi) were studied at different concentrations of the two substances. The Ki values for glucose-6-P were 0.03, 0.11, and 0.16 m m at 0.05, 10, and 30 m m Pi, respectively. Insulin, growth hormone, and other hormones had no effect on hexokinase activity in the presence or absence of glucose-6-P and Pi. Studies on the effect of different inhibitors and the specificity of the enzyme are presented.

Antiacetylcholinesterase activity of quaternary ammonium compounds of 2-methyl-3(2′-)pyridyl-4-quinazolone [QZ-2′] and 2-methyl-3(4′-)pyridyl-4-quinazolone [QZ-4′] has been investigated. Acetylcholinesterase activity of rat brain homogenates was determined colorimetrically, with acetylthiocholine as substrate. Both series of these quaternary compounds inhibited acetylcholinesterase competitively. With QZ-4′ derivatives, it was found that an increased inhibition was dependent upon the number of carbon atoms of the alkyl chain at the pyridinium nitrogen, whereas no such effect was observed with QZ-2′ compounds. The possible mechanism of action for such dissimilarity in enzyme inhibition has been discussed.