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In this note, we consider the following problem: given a connected graph G , can we reduce the domination number of G by using only one edge contraction? We show that the problem is polynomial-time solvable on ( P 3 + k P 2 ) -free graphs for any k ≥ 0 which can be combined with former results to obtain a complexity dichotomy of the problem on H -free graphs.

In the process combination of Hammering Turning, the workpiece surface is microtextured during machining by means of a multi-axis superimposed oscillation of the cutting tool. These microtextures are formed by plastic deformation of the surface layer in a process phase without material removal. In this paper, the formation of the microtexture in the originally three-dimensional process is investigated in simplified analogue 2D FEM simulations. This therefore only represents the processes and mechanisms directly below the cutting edge. The influence of the tool orientation on the plastic material flow and the formation of the microtexture as well as the residual stresses in the surface layer is investigated

In this paper, we study the problem of deciding whether the total domination number of a given graph G can be reduced using exactly one edge contraction (called 1 -Edge Contraction( γ t ) ). We focus on several graph classes and determine the computational complexity of this problem. By putting together these results, we manage to obtain a complete complexity dichotomy for H-free graphs.

Low-noise quantum frequency conversion in periodically-poled nonlinear crystals has proved challenging when the pump wavelength is shorter than the target wavelength. This is - at least in large part - a consequence of the parasitic spontaneous parametric down-conversion of pump photons, whose efficiency is increased by fabrication errors in the periodic poling. Here we characterise the poling quality of commercial periodically-poled bulk potassium titanyl phosphate (ppKTP) by measuring the sum-frequency generation (SFG) efficiency over a large phase mismatch range from 0 to more than 400$\pi$. Over the probed range the SFG efficiency behaves nearly ideally and drops to a normalised efficiency of $10^{-6}$. Our results demonstrate that any background pedestal which would be formed by random duty cycle errors in ppKTP is substantially reduced when compared to periodically poled lithium niobate. The standard deviation of the random duty cycle errors can be estimated to be smaller than 2% of the domain length. From this, we expect a noise spectral density which is at least one order of magnitude smaller than that of current state-of-the-art single-step frequency converters., Comment: 5 pages, 4 figures, 1 table

China had a system of medicine long before the advent of scientific medicine in the West. The first book about it, the Su Wen Nei Ching, was written about 300 B.C., and its detailed description of some medical phenomena cannot be surpassed even today. Despite the fact that much of the terminology is metaphysical, this traditional system of Chinese medicine is at the same time very much down to earth, being largely the result of minute observations. Consequently the symptoms of many diseases are much better described in traditional Chinese textbooks than in their modern scientific Western counterparts. Reading the Chinese books indeed opens up a new vista to a Western doctor, transforming the small range of obvious symptoms he learned at a Western medical school into a vast panorama of interconnected phenomena. It would seem that, with his reliance on laboratory procedures, the Western doctor may have been gradually losing this art of close observation; perhaps it is only artists who retain it today.

Acupuncture is of no use, or for the optimist of perhaps marginal use, in sensorineural hearing loss, contrary to what is popularly described in China. 5% or less of patients with tinnitus are helped. It is of moderate help in certain types of vertigo, acute labyrinthitis and some aspects of Meniere's disease, whilst it is of great benefit in motion sickness.The treatment is of moderate benefit in ‘nasal catarrh’, sinusitis and recurrent tonsillitis. It is the treatment of first choice in most forms of headache.May I take this opportunity to endorse the critical commentary of Dr. Beagley and his colleagues of the Rawson Report as expressed in your Journal and Hearing and also in the B.M.J, I will add a few of my own comments concerning what are, in my opinion, yet further deficiencies of this otherwise informative and well written report.

Acupuncture analgesia was performed on 100 occasions in 35 subjects. In 10% of cases the resulting analgesia was considered just adequate for surgery, and in 65% mild analgesia was produced but insufficient for surgery, whilst in the remaining 25 % there was only minimal analgesia, if any. Some of the subjects with mild analgesia could have been sufficiently anaesthetized for surgery if the pain of the stimulus had been increased to an unacceptably high level.