Disappearing subdural hematomas in children

Serum glucose and plasma C-peptide response to i.v. glucagon administration was evaluated in 24 healthy dogs, 12 dogs with untreated diabetes mellitus, 30 dogs with insulin-treated diabetes mellitus, and 8 dogs with naturally acquired hyperadrenocorticism. Serum insulin response also was evaluated in all dogs, except 20 insulin-treated diabetic dogs. Blood samples for serum glucose, serum insulin, and plasma C-peptide determinations were collected immediately before and 5, 10, 20, 30, and (for healthy dogs) 60 minutes after i.v. administration of 1 mg glucagon per dog. In healthy dogs, the patterns of glucagon-stimulated changes in plasma C-peptide and serum insulin concentrations were identical, with single peaks in plasma C-peptide and serum insulin concentrations observed approximately 15 minutes after i.v. glucagon administration. Mean plasma C-peptide and serum insulin concentrations in untreated diabetic dogs, and mean plasma C-peptide concentration in insulin-treated diabetic dogs did not increase significantly after i.v. glucagon administration. The validity of serum insulin concentration results was questionable in 10 insulin-treated diabetic dogs, possibly because of anti-insulin antibody interference with the insulin radioimmunoassay. Plasma C-peptide and serum insulin concentrations were significantly increased (P < .001) at all blood sampling times after glucagon administration in dogs with hyperadrenocorticism, compared with healthy dogs, and untreated and insulin-treated diabetic dogs. Five-minute C-peptide increment, C-peptide peak response, total C-peptide secretion, and, for untreated diabetic dogs, insulin peak response and total insulin secretion were significantly lower (P < .00l) in diabetic dogs, compared with healthy dogs, whereas these same parameters were significantly increased (P < .01) in dogs with hyperadrenocorticism, compared with healthy dogs, and untreated and insulin-treated diabetic dogs. Although not statistically significant, there was a trend for higher plasma C-peptide concentrations in untreated diabetic dogs compared with insulin-treated diabetic dogs during the glucagon stimulation test. Baseline C-peptide concentrations also were significantly higher (P < .05) in diabetic dogs treated with insulin for less than 6 months, compared with diabetic dogs treated for longer than 1 year. Finally, 7 of 42 diabetic dogs had baseline plasma C-peptide concentrations greater than 2 SD (ie, > 0.29 pmol/mL) above the normal mean plasma C-peptide concentration; values that were significantly higher, compared with the results in healthy dogs (P < .001) and with the other 35 diabetic dogs (P < .001). In summary, measurement of plasma C-peptide concentration during glucagon stimulation testing allowed differentiation among healthy dogs, dogs with impaired beta-cell function (ie, diabetes mellitus), and dogs with increased beta-cell responsiveness to glucagon (ie, insulin resistance). Plasma C-peptide concentrations during glucagon stimulation testing were variable in diabetic dogs and may represent dogs with type-1 and type-2 diabetes or, more likely, differences in severity of beta-cell loss in dogs with type-1 diabetes.     

The Volvo Uddevalla Plant

Volvos plants at Kalmar and, more recently at Uddevalla, have become noted throughout the world for their sociotechnical design and high levels of performance, breaking with mass production norms. Hence the statement from Volvo that both plants are to be closed, in order to meet the competitive threat from Japan, has come as a shock and a disappointment to those who saw them as embodying a viable alternative to lean production. This paper makes the case that Uddevalla had a productive and commercial potential unmatched elsewhere in the Volvo group, and that the decision to close the plant must have been taken on other grounds.     

Model Driven Architecture

Bei der Model Driven Architecture (MDA) bilden Modelle die zentralen Elemente des Softwareentwicklungsprozesses. Ziel ist es, plattformspezifische Modelle möglichst automatisiert aus plattformunabhängigen Modellen abzuleiten. Dadurch soll der Aufwand der Softwareentwicklung verringert und die Adaptierung an neue Technologien erleichtert werden.*Vorschläge an Prof. Dr. Frank Puppe oder Dieter Steinbauer Alle „Aktuellen Schlagwörter“ seit 1988 finden Sie unter: www.ai-wuerzburg.de/as     

Putting it all together – Formal verification of the VAMP

In the verified architecture microprocessor (VAMP) project we have designed, functionally verified, and synthesized a processor with full DLX instruction set, delayed branch, Tomasulo scheduler, maskable nested precise interrupts, pipelined fully IEEE compatible dual precision floating point unit with variable latency, and separate instruction and data caches. The verification has been carried out in the theorem proving system PVS. The processor has been implemented on a Xilinx FPGA. A shorter version of this article with the title “Instantiating uninterpreted functional units and memory system: functional verification of the VAMP” appeared in [8]. The work reported here was done while all the authors were with Saarland University.     

Controlled undercooling of liquid iron in contact with ZrO2 and MgO substrates under varying oxygen partial pressures

The objective of this study is to determine the conditions under which the inclusions present in liquid steel can act as heterogeneous nucleants for solidification. In order to study the factors that define the undercooling of a given metal/oxide couple, the undercooling of a pure iron sessile droplet in contact with Al₂O₃, ZrO₂, and MgO substrates was measured under controlled oxygen partial pressures by observing droplet recalescence. The results showed that the undercooling of iron, in contact with a particular substrate, did not have a unique value, but was significantly affected by the oxygen content on the gas phase. For oxygen partial pressures between 10⁻²¹ and 10⁻¹⁹, the undercooling of iron on ZrO₂ substrates was stable and around 290 °C. In the same range of oxygen partial pressure, the undercooling of iron on MgO substrates remained below 100 °C due to the low stability of this oxide. At lower oxygen contents, substrate decomposition might be the cause for the observed drop in the undercooling of iron on ZrO₂ substrates to below 100 °C. The undercooling also decreased for increasing oxygen content as verified when the gas was changed from gettered Ar/Ar-H₂ to CO/CO₂ mixtures. The variation in undercooling was related to the wetting of the substrate by the liquid metal, where the deep undercooling observed in the ZrO₂ experiments occurred when the highest contact angle between the liquid metal and the substrate was achieved.     

IPv6 delay and loss performance evolution

Although packet delay and loss are two important parameters of the Internet performance, to the best of our knowledge, the evolution of large‐scale IPv6 delay and loss performance has previously not been studied. In this paper, we analyze more than 600 end‐to‐end IPv6 paths between about 26 testboxes of RIPE Network Coordination Centre over two years, and compare the delay and loss performance over time with their IPv4 counterparts. We present and discuss the measurement methodologies and show that IPv6 paths have a higher delay and loss than their IPv4 counterparts. The main reason for the worse performance stems from IPv6‐in‐IPv4 tunnels rather than from native IPv6 paths and such tunnels are still widely used today. Copyright © 2007 John Wiley & Sons, Ltd.