Thyroid function in relation to bile lipids and bile acids

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SELF-RADIATION PRODUCTS FORMED FROM 3,5,3'-TRI-IODO-L-THYRONINE LABELLED WITH131I

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Density functional theory of the trapped Fermi gas in the unitary regime

We investigate a density-functional theory (DFT) approach for an unpolarized trapped dilute Fermi gas in the unitary limit . A reformulation of the recent work of T. Papenbrock [Phys. Rev. A, {\bf 72}, 041602(R) (2005)] in the language of fractional exclusion statistics allows us to obtain an estimate of the universal factor, $\xi_{3D}$, in three dimensions (3D), in addition to providing a systematic treatment of finite-$N$ corrections. We show that in 3D, finite-$N$ corrections lead to unphysical values for $\xi_{3D}$, thereby suggesting that a simple DFT applied to a small number of particles may not be suitable in 3D. We then perform an analogous calculation for the two-dimensional (2D) system in the infinite-scattering length regime, and obtain a value of $\xi_{2D}=1$. Owing to the unique properties of the Thomas-Fermi energy density-functional in 2D our result, in contrast to 3D, is {\em exact} and therefore requires no finite-$N$ corrections

Advocating for the inclusion of operatic collaborative piano curricula in higher education: Informing curricula through lived experience

The purpose of this article was to examine how the lived experiences of five professional collaborative pianists during the 35th International Hans Gabor Belvedere Singing Competition, that was held in Cape Town in 2016, could inform the inclusion of new curricula for specialised operatic collaborative piano modules in tertiary institutions. Based on the literature reviewed and themes that emerged from the data, a curriculum could include the following aspects: a knowledge of the rules of lyric diction in foreign languages; excellent sight-reading skills; knowledge of the art of orchestral reduction and repertoire; the ability to transcribe and reduce full opera scores. One personal skill that is not often developed and should also be included is the ability of a pianist to evince empathy when working with singers

Riemann zeros, prime numbers and fractal potentials

Using two distinct inversion techniques, the local one-dimensional potentials for the Riemann zeros and prime number sequence are reconstructed. We establish that both inversion techniques, when applied to the same set of levels, lead to the same fractal potential. This provides numerical evidence that the potential obtained by inversion of a set of energy levels is unique in one-dimension. We also investigate the fractal properties of the reconstructed potentials and estimate the fractal dimensions to be $D=1.5$ for the Riemann zeros and $D = 1.8$ for the prime numbers. This result is somewhat surprising since the nearest-neighbour spacings of the Riemann zeros are known to be chaotically distributed whereas the primes obey almost poisson-like statistics. Our findings show that the fractal dimension is dependent on both the level-statistics and spectral rigidity, $\Delta_3$, of the energy levels.Comment: Five postscript figures included in the text. To appear in Phys. Rev.

Exact results for a charged, harmonically trapped quantum gas at arbitrary temperature and magnetic field strength

An analytical expression for the first-order density matrix of a charged, two-dimensional, harmonically confined quantum gas, in the presence of a constant magnetic field is derived. In contrast to previous results available in the literature, our expressions are exact for any temperature and magnetic field strength. We also present a novel factorization of the Bloch density matrix in the form of a simple product with a clean separation of the zero-field and field-dependent parts. This factorization provides an alternative way of analytically investigating the effects of the magnetic field on the system, and also permits the extension of our analysis to other dimensions, and/or anisotropic confinement.Comment: To appear in Phys. Rev.

An Agronomic Evaluation of Grazing Maize Combined with Companion Crops for Sheep in Northwestern KwaZulu-Natal, South Africa

Northwestern KwaZulu-Natal (KZN), in South Africa, is well known for its sheep production from natural rangeland in summer (October to May). During winter however, the nutritional value of the rangeland cannot maintain young growing sheep or pregnant and lactating ewes. With this in mind Lyle (1991) suggested the use of planted pastures for the winter. Crichton, Gertenbach & Henning (1998) and Esterhuizen & Niemand (1989) suggested maize crop residues for both cattle and sheep during winter, whereas Moore (1997) evaluated grazing maize (not harvested) for this purpose. He found that the protein content of the crop was inadequate and for this reason, protein rich companion crops were evaluated in this study

What inspires birders to migrate South towards Africa? A quantitative measure of international avitourist motivation

Despite the rapid growth of avitourism (birding) globally, the international market potential of avitourism is not fully utilised. This research endeavoured to develop a multidimensional measure of avitourist motivation and to investigate the relative importance of the different dimensions or factors of avitourist motivation. Based on an in-depth review of the literature, a measure of birder motivation was developed. The research instrument was evaluated by a group of birding experts. The instrument was further evaluated and refined based on primary data gathered from 439 visitors to the British Birdwatching Fair and the Dutch Vogelfestival. Confirmatory factor analysis was used to evaluate the dimensionality and fit of the instrument based on the proposed factorial structure. Finally, a second-order confirmatory factor analysis model for avitourist motivation revealed higher-order constructs, namely wellbeing, intellectual activity, social interaction and photography. The results suggest that the photography dimension could be excluded as a motivational factor, and that birders consider aspects of wellbeing (emotional, spiritual, physical and mental stimulation) as the most important factors that motivate birding.Keywords: avitourism (birding tourism), bird fairs, travel motivations, second-orderconfirmatory factor analysi