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Alpha Versionen sind Lehrbücher, Gesetze, Produkthochglanzprospekte, Aktienneuemissionsanzeigen, Regierungserkl?rungen. Dahinter ist das Reale. Hinter den Lehrbüchern die vorlesende Forscherpers?nlichkeit, hinter dem Prospekt der Rat des erfahrenen Fachverk?ufers. Alpha Versionen meiden Urteile, Meinungen und Leidenschaftlichkeit. Diese Kolumne ist kompromi?los beta..     

Intrusion Prevention Systems (IPS) destined to replace legacy routers

Whether the term is evolution or revolution, corporate network managers must have noticed that change is in the air. Just as network design changed with the implementation of cost effective routers to replace legacy network bridging devices, the design rulebook is once again under revision.     

Räsonanz!

Ohne Zusammenfassung     

The common occurrence of furan fatty acids in plants

The observation that F-acids (1) occur in rat chow initiated a search for F-acids in human diet. We observed that the amount of F-acids with a pentyl side chain in α-position taken up with a one-day diet correlates well with the amount of excreted degradation products, the pentyl urofuran acids (2), (3) and (4). Therefore it can be concluded that F-acids with a pentyl side chain are not produced in the human body but are introduced through the diet. The origin of F-acids carrying an α-propyl side chain is less clear. The amount of propyl-urofuran acids (2) and (3) excreted in urine was found in one case out of three to be five times higher than the amount of F-acids carrying a propyl group in α-position taken up by the diet. Therefore, it can presently not be excluded that a portion of the propyl F-acids is produced by the body. F-acids found in human food are mainly introduced into the body by vegetables and fruits. F-acids were found also in birch leaves in considerable amounts, as well as in grasses, dandelion and clover leaves. Thus, we can conclude that F-acids are common constituents of plants.     

Priming and aging: an electrophysiological investigation of N400 and recall

Twenty young (20.5 years) and 20 middle-aged academics (57.2 years) performed a priming-recall task which was presented in three blocks. In each block, participants read 40 word pairs after which a recall task had to be carried out. Half of the word pairs were highly associated while the others were low associated. Targets showed the N400 of the middle-aged group to be both delayed and smaller in amplitude for low-associated items. N400 of primes, however, showed no age-related latency difference but was smaller for the middle-aged group due to a positive shift. It is argued that this shift possibly indicates age differences in semantic activation or buildup of context. A reanalysis showed individual differences in word pair processing to depend on recall performance. In general, high recallers were found to show a much larger differentiation between low- and high-associated targets. This resulted from a much larger N400 component elicited by low-associated targets and a more positive ERP in the N400-region for the high-associated targets. It is suggested that the middle-aged subjects activated the expected target word to a level at least equivalent to the younger subjects, but that the activated network itself was larger/less selective particularly in subjects showing a low recall.     

Fluid Velocity Measurements in Electro-Vortical Flows

This class of flows is characterized by the feeding of strong electrical currents into a volume of liquid metal. A prominent example of industrial interest is electrode-welding, where the current is supplied via a locally restricted area, leading to high current densities. The interaction of these currents with their own magnetic field drives flows that exhibit phenomena such as formation of jets and the pinch effect. Further increasing the current may lead to disruption of the melt column accompanied by a discharge. This can be used for a liquid metal current limiter with self-healing properties. Local measurements of the flow structures are of obvious interest for a better understanding of these phenomena. This paper will give results from a systematic study of the flow structure performed by means of our mechano-optical velocity probe. The measured flow structure of the evolving jet was found to be in reasonable agreement with our numerical simulations.     

IS QUALITY ENGINEERING AN OXYMORON?

It is my purpose in this editorial to offer some highly personal and likely controversial views on the state of statistics and the quality profession. These views are based on my personal experiences and prejudices-especially those of my 10 years as an independent statistical consultant. I wish to particularly absolve my current employer, Merck and Company, and my colleagues there of any guilt by association. The opinions rendered here are entirely my own and in no way represent Merck's practices or policies, Mea culpa.     

Scale-up von Destillationskolonnen

Scale-up of Distillation Columns. In spite of remarkable advances in the development of computer programs for calculations on distillation columns, it is frequently still impossible to design them without experimental testing. Economic constraints demand use of miniaturised test plant, thus enhancing the importance of laboratory measurements. A system is presented for scale-up of separation which required information from laboratory experiments, includes data from reference columns, and takes account of models of fluid dynamics and mass transfer. The special feature of this approach lies in the free choise of internals, both in the laboratory and in the designed column.