Block partitions: an extended view

Given a sequence $S=(s_1,\dots,s_m) \in [0, 1]^m$, a block $B$ of $S$ is a subsequence $B=(s_i,s_{i+1},\dots,s_j)$. The size $b$ of a block $B$ is the sum of its elements. It is proved in [1] that for each positive integer $n$, there is a partition of $S$ into $n$ blocks $B_1, \dots , B_n$ with $|b_i - b_j| \le 1$ for every $i, j$. In this paper, we consider a generalization of the problem in higher dimensions

REACTION OF TRIALKYL PHOSPHITES AND a-HALOKETONES IN APROTIC MEDIA (PERKOW-ARBUZOV REACTION) AND IN PROTIC SOLVENTS

The authors suggest a new reaction mechanism for the Perkow-Arbuzov reaction yielding vinyl phosphates and B-keto phosphonates. For the reaction of a-haloacetophenones and trialkyl phosphites in alcohol or acetic acid giving 3 products a uniform mechanism involving again a common intermediate was assumed. In the course of our work the applicability of Hammett's equation has been extended for studying parallel and braching reactions, as well

Complete Solution for Stresses in Terms of Stress Functions. Part I: Derivation from the Principle of Virtual Work

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Complete Solution for Stresses in Terms of Stress Functions. Part II: Modification of Variational Principles

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Alterations of the Intracellular Water and Ion Concentrations in Brain and Liver Cells During Aging as Revealed by Energy Dispersive X-Ray Microanalysis of Bulk Specimens

Age dependence of the intracellular concentrations of monovalent ions (Na+, K+ and Cl-) was examined in 1, 11 and 25-month-old rat brain and liver cells by using energy dispersive X-ray microanalysis. The in vivo concentrations of Na+, K+ and Cl- ions were calculated from two different measurements: The elemental concentrations were measured in freeze-dried tissue pieces, and the intracellular water content was determined by means of a recently developed X-ray microanalytic method, using frozen-hydrated and fractured bulk specimens as well as subsequent freeze-drying. All the single monovalent ion concentrations and consequently, also the total monovalent ion content showed statistically significant increases during aging in brain cortical neurons. A 3-6% loss of the intracellular water content was accompanied by a 25-45% increase of the monovalent ionic strengths by the age of 25 months. A membrane protective OH radical scavenger (centrophenoxine) reversed the dehydration in the nerve cells of old animals, resulting in a decrease of the intracellular ion concentrations. Aging has a less prominent effect on the water and ion contents of the hepatocytes. The degree of water loss of cytoplasm exceeds that of the nuclei in the liver, suggesting that dominantly the translational steps can be involved in the general age altered slowing down of the protein synthetic machinery, predicted by the membrane hypothesis of aging (Zs.- Nagy, 1978)

Discovery of the spectroscopic binary nature of the classical Cepheids FN Aql and V1344 Aql

We present the analysis of photometric and spectroscopic data of two classical Cepheids, FN Aquilae and V1344 Aquilae. Based on the joint treatment of the new and earlier radial velocity data, both Galactic Cepheids have been found to be a member in a spectroscopic binary system. To match the phases of the earlier radial velocity data correctly with the new ones, we also determined the temporal behaviour of the pulsation period of these Cepheids based on all available photometric data. The O-C graph covering about half century shows slight changes in the pulsation period due to stellar evolution for both Cepheids.Comment: 7 pages, 6 figures, 7 tables, accepted for publishing in the MNRA