A pilot school health service in southwestern Swaziland, 1961, 62, 63

Swaziland is a British Protectorate of approximately 6,700 square miles. It is a subtropical country, border in the East by Mozambique and in the North, West and South by the Transvaal. There are approximately 270,000 Africans and 10,000 persons of other races living in the Territory. The country is divided into Highveld, Middleveld and Lowveld regions. The work described here was carried out in the South Western highveld. This is mountainous terrain, with an approximate altitude of 3,500 feet and an annual rainfall of about 30". The terrain is a succession of mountains and valleys, with several perennial streams and rivers coursing through it. The climate is variable, with hot summers and cold winters, with rainfall predominantly in the summer. Large man made forests are scattered throughout the area, and there is some cutting and processing of timber, but industries as such are not found in that part of the Territory

Theory of the vibrations of sodium chloride

The interest in the frequency spectrum of the thermal vibrations in a crystal arose chiefly in connection with the problem of the specific heat of crystals at low temperatures, Debye' s theory of the specific heat, however, has been so successful that the actual determination of the frequency spectrum according to Born and v.Karman (1912) has been pushed into the background. But recent investigations, especially those of Blackman (1938, 1935, 1937) have shown that appreciable deviations from Debye's theory should occur according to the correct atoruistic treatment. These deviations appear to be most pronouneed _ear the absolute zero of temperature. It, therefore, seemed desirable to calculate the exact frequency spectrum of a crystal.The first attempt to calculate the frequency spectrum of a crystal was made iIty Born and v.Karrlian in their original paper. They assumed only quasi -elastic forces between neighbouring particles. Later calculations have been made for ionic lattices, assurlinghereal forces in the crystal. The chAif difficulty in that calculation has always been the long range of the Joulonrb force which makes a direct summation over all lattice points impossible.Born and Thompson (1934) suggested a way of transforming these stuns into more rapidly convergent expressions using a method developed by Ewald (1921) and Thompson (1935) has given the final formulae for the coupling coefficients due to the Coulomb force in the equation of motion, but in his paper a slight mistake occurred in the definition of the coefficients and so far no numerical results of these calculations have been published. Broch (1937) has given formulae for the case of an one dimensioonnaall lattice mating use of Epstein's Zeta functions; Herzfeld and Lyddane (1938) have used an extension of Madelung' s method (1918) and they have given some numerical results; but their formulae are rather complicated so that one cannot expect to compute the whole frequency spectrum by this method. Moreover, the problem. of the thermal oscillations of an ionic lattice is not a purely electrostatic problem and this point has not been made sufficiently clear by Herzfeld and Lyddane. This applies especially to the case of the residual rays and the question whether the potential, from which the coupling coefficients are obtained, satisfies the Laplace equation or Poisson's equation.In this paper we have used Ewald's method mentioned above, but interpreted and extended by him in a recent paper (1938). By this method one obtains comparatively simple and quickly convergent expressions for the coupling coefficients in the equation of motion which allow a numerical calculation to an arbitrary degree of accuracy. Because of the good convergence it has not been too laborious to compute numerical values for 48 different modes of vibration,In sections III III we give the derivation of these expressions by treating the problem as an electrostatic problem, neglecting the retardation; but the proper way of solving our problem is, to find a solution of :._axwell's equation for the electromagnetic field in the crystal, 'this will be done in Section IV, From this field the force exerted on a particle and the coupling coefficients can be obtained (Section V), We shall see that in this proper treatment the case of infinitely long waves plays a special role and must be considered separately, In all the other cases this treatrIent leads to the same result as the electrostatic derivation, If we define a potential function from which the coupling coefficients are obtained as second derivatives, this potential satisfies in general Laplace's equation; but in the special case of infinitely long waves it satisfies I'oisson's equation,In Section VI the coupling coefficients for the ra Cl lattice are given and in Sec :ion VII the contribution due to the repulsive forces is calculatèd, In Section VIII the equations for the coupling coefficients are checked by deriving from them formulae for the elastic constants,Finally, in Section IX the coefficients have been calculated and in section X the frequencies for 17 modes of vibrations, and the spectrum has been discussed

Rho meson broadening and dilepton production in heavy ion collisions

The modification of the width of the rho meson due to in-medium decays and collisions is evaluated. In high temperature and/or high density hadronic matter, the collision width is much larger than the one-loop decay width. The large width of the meson in matter seems to be consistent with some current interpretations of the e+e mass spectra measured at the CERN/SPS

Rho meson broadening in hot and dense hadronic matter

The modification of the width of rho mesons due to in-medium decays and collisions is evaluated. The decay width is calculated from the imaginary part of the one-loop selfenergy at finite temperature. The collision width is related to the cross sections of the rho + pion and the rho + nucleon reactions. A calculation based on an e ective Lagrangian shows the importance of including the direct pho pi - > pho pi scattering which is dominated by the a1 exchange. A large broadening of the spectral function is found, accompanied by a strength suppression at the pole. http://www.arxiv.org/abs/nucl-th/981205

Intermediate mass excess of dilepton production in heavy ion collisions at BEVALAC energies

Dielectron mass spectra are examined for various nuclear reactions recently measured by the DLS collaboration. A detailed description is given of all dilepton channels included in the transport model UrQMD 1.0, i.e. Dalitz decays of π, η, ω, ή mesons and of the (1232) resonance, direct decays of vector mesons and pn bremsstrahlung. The microscopic calculations reproduce data for light systems fairly well, but tend to underestimate the data in pp at high energies and in pd at low energies. These conventional sources, however, cannot explain the recently reported enhancement for nucleus-nucleus collisions in the mass region 0.15GeV ≤ Me+e- ≤ 0.6GeV. Chiral scaling and ω meson broadening in the medium are investigated as a source of this mass excess. They also cannot explain the recent DLS data

Vibronische Kopplung und dynamisch verzerrte Strukturen in Hexahalogenotelluraten(IV): Ergebnisse aus Tieftemperatur-Röntgenbeugungsuntersuchungen (300—160 K) und aus FTIR-spektroskopischen Experimenten (300—5 K) [1]

From theoretical considerations a dynamically distorted octahedron as a result of vibronic coupling between the ground state and the first excited state should exist for 14 electron AX6E systems like TeX62- . A high symmetry crystal field yielding at least a center of symmetry for the Te position stabilizes this fluctuating structure, otherwise statical distortion will be observed. From X-ray diffraction experiments on antifluorite type compounds A2TeX6 (A = Rb. Cs: X = Cl, Br) the averaged structure (m3̅m symmetry) of the anions was found even at very low temperatures. The thermal parameters are not significantly different from those of similar SnX62 compounds. Distortions therefore are very small and are evident from FTIR spectroscopic meas­urements only. Here very broad T1u-deformation vibration bands are observed down to tempera­tures <10 K without splitting: Astatically distorted species could not be frozen out. In contrast to XeF6 for TeX62- the energy gap between the threefold, fourfold or sixfold minima of the potential surface (according to the symmetry of one component of the T1u-vibration) is very small and shifted to temperatures lower than reached with the devices used for these experiments

Ökologisches Verantwortungsbewusstsein und Ansatzpunkte zur Förderung im Unternehmen

In diesem Beitrag wird eine Konzeption zum ökologischen Verantwortungsbewusstsein vorgestellt, die sich auf folgende Teilbereiche bezieht: (a) auf das ökologische Denken bzw. Strukturwissen zu Umweltproblemen; (b) auf ökologische Kontrollvorstellungen zu Handlungsmöglichkeiten angesichts dieser Probleme sowie (c) auf ökologische Moral- bzw. Wertvorstellungen. Zuerst geht es um die theoretischen und empirischen Zusammenhänge zwischen diesen Teilbereichen. Außerdem wird auf Bezüge zum tatsächlichen Umwelthandeln eingegangen. Anschließend werden Konsequenzen für die Förderung des ökologischen Verantwortungsbewusstseins und des Umwelthandelns im Unternehmen aufgezeigt. Diese zielen vor allem auf den Bereich der Umweltbildung, auf die Integration individuellen Umwelthandelns in kollektive Handlungsstrategien und auf die Entwicklung einer ökologischen Konfliktkultur im Unternehmen.The conception of the awareness of ecological responsibility presented in this paper comprises three subareas: (a) knowledge of structural aspects of ecological problems, (b) ecological control attributions, and (c) ecological moral judgments. First, theoretical and empirical connections between the subareas are discussed, as are their effects on actual ecological behavior. Second, consequences for the advancement of ecological responsibility and behavior in organizations will be shown. These primarily concern the areas of environmental education, the integration of individual ecological behavior into collective strategies, and the development of a corporate environmental "conflict culture"