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It is known (G. Choquet, G. Mokobodzki) that a Baire-one affine function on a compact convex set satisfies the barycentric formula and can be expressed as a pointwise limit of a sequence of continuous affine functions. Moreover, the space of Baire-one affine functions is uniformly closed. The aim of this paper is to discuss to what extent analogous properties are true in the context of general function spaces. In particular, we investigate the function spaceH(U), consisting of the functions continuous on the closure of a bounded open setU⊂ℝm and harmonic onU, which has been extensively studied in potential theory. We demonstrate that the barycentric formula does not hold for the spaceB1b(H(U)) of bounded functions which are pointwise limits of functions from the spaceH(U) and thatB1b(H(U)) is not uniformly closed. On the other hand, every Baire-oneH(U)-affine function (in particular a solution of the generalized Dirichlet problem for continuous boundary data) is a pointwise limit of a bounded sequence of functions belonging toH(U). It turns out that such a situation always occurs for simplicial spaces whereas it is not the case for general function spaces. The paper provides several characterizations of those Baire-one functions which can be approximated pointwise by bounded sequences of elements of a given function space. [ABSTRACT FROM AUTHOR]

Summary Lumbar disc operations have been performed in Brno since 1952 and from the very beginning they are performed under regional anaesthesia. Since 1965 until 1999 about 16000 operations for herniated discs have been performed here. The number of operations doubled with the foundation of the second neurosurgical department in Brno in 1992. Lumbar disc surgery represents 25% of the operation spectrum in our department. Epidural anaesthesia is advantageous for less risk of some complications compared with general anaesthesia and enables communication between the surgeon and the patient. Other advantages are: less visible bleeding in the operative field due to the lateral position and the fact that the surgeon can sit during the operation. On a long-term basis we found 4–5% had further surgery for reccurent problems. Objective neurological evaluation 6 weeks after the operation showed improvement in 92% of patients. The patients themselves consider their status as very good or satisfactory in 82% (median 3 years after the operation). Besides a correctly performed operation we emphesize also the role of correct diagnosis (good correlation between the patient's problems and CT scan finding) for a good treatment result. [ABSTRACT FROM AUTHOR]