The Szigliget maar/diatreme, Bakony- Balaton Highland Volcanic Field (Hungary)

A preliminary volcanological mapping has been carried out in the western part of the Bakony- Balaton Highland Volcanic Field (BBHVF) around Szigliget (Hungary) village. Pyroclastic rocks have been found building up the three distinct hillsides in the area. The pyroclastic rock beds in each hillside show similar north-westward dip direction and similar textural and compositional characteristics, suggestive of a complex but closely related volcanic system in the area. The pyroclastic deposits have been grouped into three units according to their textural, compositional and stratigraphic characteristics. Unit 1 which represents the lowermost stratigraphic position crops out in the southern side of the study area. It consists of coarse-grained, matrix-supported massive to weakly bedded, accidental lithic clast-rich, block-bearing lapilli tuffs / tuff breccias, extremely rich in deep-seated accidental lithic and peridotite lherzolite clasts. Unit 2 which represents an intermediate stratigraphic position crops out in the southern and north-east hilltops. It consists of coarse-grained accidental lithic clast-rich, normal graded, bedded, vitric lapilli tuffs / tuff beds. Deep-seated accidental lithic clasts are common, but large peridotite lherzolite fragments are relatively rare. Unit 3 which represents the highest stratigraphic position in the area crops out in the northwestern side. It consists of fine-to-coarse grained, bedded, accidental lithic clast-rich vitric lapilli tuff / tuff beds. Deep-seated lithic clasts as well as peridotite lherzolite fragments are rare. Accidental lithic clasts, derived from shallow prevolcanic strata (Neogene sediments), have a dominant proportion of pyroclastic rocks in this unit. In each unit the volcanic glasses are angular, non- to highly vesiculated tephrite to phono-tephrite shards. The presence of sideromelane glass shards and the large amount of accidental lithic clasts in beds from each units indicate subsurface phreatomagmatic explosive processes during formation of pyroclastic rocks at Szigliget. The pyroclastic rocks are interpreted as part of a former crater rim deposits around maar basin which subsequently subsided inward into a vent. Unit 1 is interpreted to be a lower diatreme deposit and Unit 2 and Unit 3 a series of near-vent pyroclastic density currents and fallout tephra

Reply to: comments to: “Volcanic geomorphology and tectonics of the Aeolian Archipelago (Southern Italy) based on integrated DEMdata” by Favalli et al.

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On-Line Haemodiafiltration versus Haemodialysis: Stable Haematocrit with Less Erythropoietin and Improvement of Other Relevant Blood Parameters

Background: Controlled randomised studies to prove improved cardiovascular stability and improved anaemia management during on-line haemodiafi ltration (oHDF) are scarce. Methods: 70 patients were treated with both haemodialysis (HD) and oHDF in a cross-over design during 2 ! 24 weeks at a dialysis dose of eKt/ V 6 1.2. Patients randomised into group A started on HD and switched over to oHDF, whereas patients in group B began with oHDF and were treated with HD afterwards. Intradialytic morbid events (IME), such as symptomatic hypotension or muscle cramps, were noted in case of appearance. Blood parameters refl ecting anaemic status, phosphate status, lipid metabolism, oxidative stress, and accumulation of advanced glycation end products were recorded either monthly or at the end of each study phase. Results: The mean incidence of IME was 0.15 IME per treatment, and there was no statistical difference between oHDF and HD. A higher haematocrit (oHDF 31.5% vs. HD 30.5%, p ! 0.01) at a lower erythropoietin dose (oHDF 4,913 vs. HD 5,492 IU/week, p = 0.02) was found during oHDF, when the sequence of HD and oHDF had not been taken into account. For the study groups, the results were less distinct: in group A, a higher haematocrit (HD 30.4% vs. oHDF 32.0%, p ! 0.01) at a comparable erythropoietin dose (HD 5,421 vs. oHDF 5,187 IU/week, ns) was observed during oHDF, whereas in group B an identical haematocrit (oHDF 30.8% vs. HD 30.7%, ns) was achieved at a reduced erythropoietin dose (oHDF 4,622 vs. HD 5,568 IU/week, p ! 0.01). During oHDF, lower levels of free and protein-bound pentosidine and of serum phosphate were found. Conclusion: In contrast to other studies, no benefi t regarding cardiovascular stability for oHDF was found, but oHDF could well offer a potential benefi t regarding anaemia correction, infl ammation, oxidative stress, lipid profi les, and calcium-phosphate product

Gide avant Paludes ou comment Narcisse devient romancier

Karatson André. Gide avant Paludes ou comment Narcisse devient romancier. In: Littératures 17, automne 1987. pp. 141-151

Newton's method in the context of gradients

This paper gives a common theoretical treatment for gradient and Newton type methods for general classes of problems. First, for Euler-Lagrange equations Newton's method is characterized as an (asymptotically) optimal variable steepest descent method. Second, Sobolev gradient type minimization is developed for general problems using a continuous Newton method which takes into account a "boundary condition" operator

Krylov improvements of the Uzawa method for Stokes type operator matrices

The paper is devoted to Krylov type modifications of the Uzawa method on the operator level for the Stokes problem in order to accelerate convergence. First block preconditioners and their effect on convergence are studied. Then it is shown that a Krylov-Uzawa iteration produces superlinear convergence on smooth domains, and estimation is given on its speed

Bifurcations for semilinear elliptic equations with convex nonlinearity

We investigate the exact number of positive solutions of the semilinear Dirichlet boundary value problem $Delta u+f(u) = 0$ on a ball in ${mathbb R}^n$ where $f$ is a strictly convex $C^2$ function on $[0,infty)$. For the one-dimensional case we classify all strictly convex $C^2$ functions according to the shape of the bifurcation diagram. The exact number of positive solutions may be 2, 1, or 0, depending on the radius. This full classification is due to our main lemma, which implies that the time-map cannot have a minimum. For the case $n>1$ we prove that for sublinear functions there exists a unique solution for all $R$. For other convex functions estimates are given for the number of positive solutions depending on $R$. The proof of our results relies on the characterization of the shape of the time-map

Reply to: comments to: “Volcanic geomorphology and tectonics of the Aeolian Archipelago (Southern Italy) based on integrated DEMdata” by Favalli et al.

No abstractPublished117-1183.6. Fisica del vulcanismoJCR Journalope