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Objective: To determine the suitability of four research methods to measure the rate of child restraint device (CRD) use and incorrect use in New Zealand and obtain data on barriers [...]

A partial pancreaticogastrodudenectomy was performed on a 66-year old man with type 2 diabetes mellitus because of an invasive, moderately differentiated adenocarcinoma in the head of the pancreas. In the adjacent grossly normal tissue of the uncinate process, there was a massive proliferation of pancreatic polypeptide (PP) cells confined to this region and showed invasive pattern. Strikingly, in the heaped area of his duodenum, there was a strikingly large number of PP, glucagon, a few insulin cells in a mini-islet–like patterns composed of glucagon and insulin cells. Among the etiological factors, the possible long-lasting effects of the GLP-1 analog, with which the patient was treated, are discussed. This is the first report in the literature of both the coexistence of a pancreatic adenocarcinoma and invasive PPoma and the occurrence of PP and insulin cells in human duodenal mucosa.

The formation of Cr2O3nanoparticles by γ-irradiation of dichromate solutions was investigated in the presence of radical scavengers, tert-butyl alcohol, nitrous oxide, and dissolved oxygen. The concentrations of CrVIand CrIIIspecies and the chemical composition and sizes of particles that were formed were measured as a function of irradiation time. A mechanism is proposed that is consistent with the observed effects of scavengers on the kinetics of reduction of CrVIin solution to solid CrIIIand the final size of Cr2O3nanoparticles that are formed. The chromium reduction occurs in three stages: Stage I involves homogeneous aqueous reduction of CrVI(aq) to CrIII(aq) followed by spontaneous condensation of Cr(OH)3, providing nucleation sites onto which CrVIand CrIIIcoprecipitate and form mixed CrVI/CrIIIoxide/hydroxide particles. In Stage II, the aqueous reduction of CrVI(aq) and CrIII(aq) reaches steady state but the adsorption of CrVIcontinues, growing the mixed CrVI/CrIIIoxide/hydroxide particles. Stage 3 involves the solid-state conversion of CrVIand CrIII, and the particles slowly convert from a mixed CrVI/CrIIIoxide/hydroxide to Cr(OH)3and then to Cr2O3. Adding a radical scavenger in solution affects the kinetics of particle formation and growth at different stages differently. This information can be used to tailor the final sizes of particles.

In 2002, the RAPid Telescopes for Optical Response (RAPTOR) project pushed the envelope of automated astronomy by becoming the first fully autonomous closedloop robotic telescope. Deployment required a fast, efficient, and reliable network technology to perform the collaborative, synchronized observations and the Telescope ALert Operation Network System (TALONS) was engineered to meet this goal. It was soon realized that the telescope systems mandate could be expanded to include monitoring the sky for anomalous and interesting behaviors in persistent sources rather than focusing on only optical transients and GRB follow-ups. But to achieve this goal we would need to make this system think and that would require the merging of the robotic telescopes assets with new technologies. The binding thread between the new technologies and RAPTOR would be an enhanced TALONS astronomical network. We have now seen that any isolated telescope system can deliver good science, but if it could cooperatively operate with a network of other telescope assets it could increase the likelihood of great science. While using the internet for communicating between distributed astronomical systems is still in its infancy, it already shows great potential (White et al. 2004) and the varied architectural techniques available offer operators great flexibility to meet their local needs and to meet a goal of greater interconnectivity. In this paper we will present the evolution of RAPTOR and TALONS into a thinking telescope system and how that effort highlights the process of designing and engineering a meta-network to meet the goal of greater interconnectivity in the astronomical community. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Laboratory. RAPTOR is a fully autonomous robotic system that is designed to identify and make follow-up observations of optical transients with durations as short as one minute. The RAPTOR design is based on Biomimicry of Human Vision. The sky monitor is composed of two identical arrays of telescopes, separated by 38 kilometers, which stereoscopically monitor a field of about 1300 square-degrees for transients. Both monitoring arrays are carried on rapidly slewing mounts and are composed of an ensemble of wide-field telescopes clustered around a more powerful narrow-field telescope called the “fovea” telescope. All telescopes are coupled to real-time analysis pipelines that identify candidate transients and relay the information to a central decision unit that filters the candidates to find real celestial transients and command a response. When a celestial transient is found, the system can point the fovea telescopes to any position on the sky within five seconds and begin follow-up observations. RAPTOR also responds to Gamma Ray Burst (GRB) alerts generated by GRB monitoring spacecraft. Here we present RAPTOR observations of GRB 021211 that constitute the earliest detection of optical emission from that event and are the second fastest achieved for any GRB. The detection of bright optical emission from GRB021211, a burst with modest gamma-ray fluence, indicates that prompt optical emission, detectable with small robotic telescopes, is more common than previously thought. Further, the very fast decline of the optical afterglow from GRB 021211 suggests that some so-called “optically dark” GRBs were not detected only because of the slow response of the follow-up telescopes. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The observation of a prompt optical flash from GRB 990123 convincingly demonstrated the value of autonomous robotic telescope systems. Pursuing a program of rapid follow-up observations of gamma-ray bursts, the Robotic Optical Transient Search Experiment (ROTSE) has developed a next-generation instrument, ROTSE-III, that will continue the search for fast optical transients. The entire system was designed as an economical robotic facility to be installed at remote sites throughout the world. There are seven major system components: optics, optical tube assembly, CCD camera, telescope mount, enclosure, environmental sensing and protection, and data acquisition. Each is described in turn in the hope that the techniques developed here will be useful in similar contexts elsewhere.

During ablative neurosurgery of movement disorders, for instance therapy of Parkinson's disease, temperature monitoring is crucial. This study aims at a quantitative comparison of measurement deviations between the maximum temperature located outside the lesioning electrode and two possible thermocouple locations inside the electrode. In order to obtain the detailed temperature field necessary for the analysis, four finite element models associated with different surroundings and with different power supplies are studied. The results from the simulations show that both the power level and the power density as well as the surrounding medium affect the temperature measurement and the temperature field in general. Since the maximum temperature is located outside the electrode there will always be a deviation in time and level between the measured and the maximum temperature. The deviation is usually 2–7 s and 3–12°C, depending on, for example, the thermocouple location and surrounding medium. Therefore, not only the measured temperature but also the relation between measured and maximum temperature must be accounted for during therapy and device design.

The presence of volatile iodine in containment buildings is one of the major safety concerns in the potential event of nuclear reactor accidents. Organic impurities in containment water, originating from various painted structural surfaces and organic materials, could have a significant impact on iodine volatility following an accident. To determine the source and magnitude of organic impurities and their effects on time-dependent iodine volatility, the dissolution for organic constituents from paints used in reactor buildings has been studied under postulated accident conditions. The studies of the organic dissolution from carbon steel coupons coated with zinc-primed vinyl, epoxy-primed polyurethane or epoxy paints over the temperature range 25-90°C are reported. Relatively large activation energies were measured for the release of the principal organic compounds from painted surfaces, suggesting it is the release of the solvents from the paint matrix rather than their diffusion through the solution that is the rate determining step for the dissolution mechanism. The similarities in the values of activation energies for the dissolution of different organic compounds from the paints suggest the release rate is independent of the nature of the painted surface or the type of organic being released from the surface. These two observations indicate that it may be possible to write a generalized rate expression for the release of organic compounds from painted surfaces in containment following an accident. The possible implications of these results for predicting iodine volatility in containment are also discussed.Key words: dissolution kinetics, organic solvents, painted surfaces, reactor accidents.

Abstract—This paper describes the coordinated results of several sets of measurements of two Leonid meteor fireballs over northern New Mexico at 1:32 and 3:06 MST, respectively, on the night of 1998 November 17. The measurements included visible band photometry on both events, as well as filtered 5890 Å all‐sky images of the Na airglow. Also, for the 3:06 a.m.event, we obtained an infrasound measurement of the hydrodynamic yield. For the 1:32 a.m.event, we obtained a set of visible band charge‐coupled device (CCD) camera images of the meteor train for times extending to 30 min after the initial impact. The measurement results have been combined to derive an optical efficiency for the intense early‐time optical flash, and the total explosion yields and masses for both of the meteors.

Abstract: The aim of this study was to develop a finite element model for simulation of the thermal characteristics of brain electrodes and to compare its performances with an in vitro experimental albumin model. Ten lesions were created in albumin using a monopolar electrode connected to a Leksell Neuro Generator and a computer-assisted video system was used to determine the size of the generated lesions. A finite element model was set up of the in vitro experiments using the same thermal properties. With a very simple heat source applied to the finite element model in the proximity of the upper part of the tip, a good agreement (no deviations in width and distance from tip but a deviation in length of −1.6 mm) with the in vitro experiments (width 4.6±0.1 mm and length 7.4±0.1 mm) was achieved when comparing the outline of the lesion. In addition, a gelatinous albumin-model was set up and compared to computer simulations resulting in deviations in width of −0.4 mm, length of −2.2 mm and distance from the tip of −0.1 mm. Hence, the utilisation of finite element model simulations may be a useful complement to in-vitro experiments.

The kinetics of disproportionation of elemental iodine to iodide and iodate ions has been studied in basic aqueous media using Raman and uv–visible spectroscopy. The IO stretching vibrations for IO−and I2OH−were observed at 430 ± 2 and 560 ± 2 cm−1, respectively. The totally symmetric stretching vibration for was observed at 685 ± 2 cm−1. The Raman results indicate that I2OH−is a linear molecule with a stronger I—O bond than IO−. The rate expression at 25 °C in 1 mol dm−3NaOH was found to bewhereThe reaction is primarily a reaction of the iodine +1 oxidation-state species IO−and I2OH−. It proceeds through the +3 oxidation-state species The following equilibrium and rate constants were determined:

This study demonstrates the first use of the microwave-induced acoustic phenomenon (MIA) for the study of ionic conducting materials such as inorganic salts and pure metals in aqueous and organic media. While the magnitude of the MIA signal is related to both the dielectric loss and the thermoelastic properties of the medium, only the thermoelastic properties are important for strongly absorbing liquids. The potential applications of MIA to microwave heating of solid surfaces and surface interactions are illustrated with copper coils.

This article traces the intellectual journey of a class of leadership students as they explored the relationship between culture and leadership through the analysis of historical scenarios. In particular, their study of the role elements of the popular culture played in the "adaptive work" of several subgroups of society in the 1920s challenges traditional conceptions of leadership. Can there be such a thing as "cultural leadership?" The author uses the students' work as a point of departure for a new and more expansive definition of leadership.

This paper presents a model course outline for an introductory course in leadership. It addresses the concept of leadership from the perspective of the liberal arts, drawing from the disciplines of history, literature, political science, philosophy, psychology, and anthropology, as well as from management studies and organizational behavior. It proceeds from a consideration of the concept of leadership to an analysis of its essential elements--leader, followers and context. The proposed course of study next turns to a consideration of the process of leadership, and an introduction to some of the skills needed to operate effectively in a leadership situation. The course ends with a discussion of the moral and ethical obligations of leadership.

The surfactant and solubilizing properties of lysophosphatidylcholine (LPC) could have industrial uses if it became available in technical quantity and purity. The two most promising routes for obtaining it are isolation from cereal starches and mono-deacylation of egg phosphatidylcholine (PC). Baker's yeast autolysed by Letters's method yielded up to 0·3 % of LPC. The phospholipase A activity of pancreatin powder gave 80 % of the theoretical yield of LPC under optimum conditions; modifications designed to facilitate scale-up reduced the yield. Base-catalysed glycerolysis at 75° gave 23 % of the theoretical yield of LPC, and a reaction between PC and ethanolamine up to 45%. The crude product from ethanolamine after acetone precipitation gave an emulsifier containing LPC, PC and long-chain N-2-hydroxyethylamide.

Chromatography on silicic acid is a powerful tool for separation of blood lipids. In one experiment, about 20 different lipids may be detected; some of these remain unidentified.

ROTSE-III is a homogeneous worldwide array of 4 robotic telescopes. They were designed to provide optical observations of γ -ray burst (GRB) afterglows as close as possible to the start of γ -ray emission. ROTSE-III is fulfilling its potential for GRB science, and provides optical observations for a variety of astrophysical sources in the interim between GRB events. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Crevice corrosion of carbon steel was investigated in different exposure environments by performing coupon exposure and electrochemical tests. The extent of corrosion on the bold surface of a carbon steel crevice coupon was more severe at 80°C than at 21°C, in aerated rather than dearated solutions, and with γ-radiation present. In contrast to normal crevice corrosion, we observed ‘inverse crevice corrosion’ behavior, the phenomenon where it is the corrosion on the bold surface that is accelerated when coupled, rather than that on the crevice surface. The coupling current measured between a crevice and a bold electrode in an electrochemical cell was also negative. This inverse crevice corrosion behavior is attributed to a significantly lower metal cation dissolution capacity of the small occluded water volume in the crevice, compared to that of the bulk water volume over the bold surface. The reduction in dissolution capacity results in faster and earlier formation of a protective oxide layer. Corrosion of the bold and crevice surfaces evolves at different rates, leading to galvanically accelerated corrosion of the bold surface. The effect of γ-radiation on corrosion evolution in different solution environments leading to inverse crevice corrosion is discussed.