The Application Of RISC Processors To Training Simulators

Report on a study of the utility of reduced instruction set computer processors as the control computers in a training simulator. Report includes a master\u27s thesis on detailed hardware design for interfacing transputer hardware to the NeXT computer

Rhodium/phospholane-phosphite catalysts give unusually high regioselectivity in the enantioselective hydroformylation of vinyl arenes

Using the phospholane-phosphite ligand, BOBPHOS, almost perfect regioselectivities and high enantioselectivities (up to 92% ee) are observed in Rh catalysed enantioselective hydroformylation of vinyl arenes. This can be achieved under solvent-free conditions.PostprintPeer reviewe

Extreme summer heat in Phoenix, Arizona (USA) under global climate change (2041-2070)

Summer extreme heat events in the arid Phoenix, Arizona (USA) metropolitan region for the period 2041-2070 are projected based on the ensemble of ten climate models from the North American Regional Climate Change Assessment Program for the SRES A2 greenhouse gas emissions scenario by the Intergovernmental Panel on Climate Change. Extreme heat events are identified by measures related to two thresholds of the maximum daily air temperature distribution for the historical reference period 1971-2000. Comparing this reference period to the model ensemble-mean, the frequency of extreme heat events is projected to increase by a factor of six to 1.9 events per summer and the average number of event days per year is projected to increase by a factor of 14. The inter-model range for the average number of EHE days per summer is larger for the projected climate, 10.6 to 42.2 days, than for simulations of the past climate simulations (1.5 to 2.4 days)

Extreme summer heat in Phoenix, Arizona (USA) under global climate change (2041-2070)

Summer extreme heat events in the arid Phoenix, Arizona (USA) metropolitan region for the period 2041-2070 are projected based on the ensemble of ten climate models from the North American Regional Climate Change Assessment Program for the SRES A2 greenhouse gas emissions scenario by the Intergovernmental Panel on Climate Change. Extreme heat events are identified by measures related to two thresholds of the maximum daily air temperature distribution for the historical reference period 1971-2000. Comparing this reference period to the model ensemble-mean, the frequency of extreme heat events is projected to increase by a factor of six to 1.9 events per summer and the average number of event days per year is projected to increase by a factor of 14. The inter-model range for the average number of EHE days per summer is larger for the projected climate, 10.6 to 42.2 days, than for simulations of the past climate simulations (1.5 to 2.4 days).Projektionen für extreme Hitzeereignisse in den Sommermonaten in Phoenix, Arizona (USA) wurden für den Zeitraum 2041-2070 unter der Annahme des SRES A2 Treibhausgasemissionsszenarios des Intergovernmental Panel on Climate Change erstellt. Dafür wurden Simulationsergebnisse eines Ensembles von zehn Klimamodellen ausgewertet, die im Rahmen des North American Regional Climate Change Assessment Programmes angewendet wurden. Die extremen Hitzeereignisse wurden mit Hilfe von Kriterien bestimmt, die auf Schwellenwerttemperaturen für die maximalen täglichen Lufttemperaturen für die Referenzperiode 1971-2000 beruhen. In der Zukunft versechsfacht sich im Ensemblemittel die Häufigkeit der Extremereignisse (~ 1.9 Ereignisse pro Sommer) im Vergleich zum Referenzzeitraum mit einer vierzehnfachen mittleren Anzahl der Hitzetage pro Sommer. Dabei vergrößert sich die Schwankungsbreite der Modelle bezüglich der mittleren Anzahl der Hitzetage pro Sommer in der Zukunft gegenüber der der Vergangenheit von 1.5-2.4 auf 10.6-42.2

Impact of deoxygenation and warming on global marine species in the 21st century

Ocean temperature and dissolved oxygen shape marine habitats in interplay with species&rsquo; physiological characteristics. Therefore, the observed and projected warming and deoxygenation in the 21st century of the world&rsquo;s oceans may strongly affect species&rsquo; habitats. Here, we implement an extended version of the Aerobic Growth Index (AGI), which quantifies whether a viable population of a species can be sustained in a particular location. We assess the impact of projected deoxygenation and warming on the contemporary habitat of 47 representative marine species covering the epipelagic, mesopelagic/bathypelagic, and demersal realms. AGI is calculated for these species for the historical period and into the 21st century using bias-corrected environmental data from six comprehensive Earth System Models. While habitat viability decreases nearly everywhere with global warming, impact of this decrease is strongly species-dependent. Most species lose less than 5 % of their contemporary habitat volume over the 21st century even at 3 &deg;C of global warming relative to preindustrial, although some individual species are projected to incur losses 2&ndash;3 times greater than that. We find that the contemporary spatiotemporal variability of O2 and temperature (and hence AGI) provides a quantifiable measure of a species&rsquo; vulnerability to change. Species&rsquo; vulnerability is the most important indicator for large (&gt;5 %) potential habitat losses &ndash; not relative or absolute changes in habitat viability (i.e., AGIrel or &Delta;AGI), temperature or O2. Loss of contemporary habitat is for most epipelagic species driven by warming of ocean water and is therefore expanded with increased levels of global warming. In the mesopelagic/bathypelagic and demersal realms habitat loss is also affected by pO2 decrease for some species. Our analysis is constrained by the uncertainties involved in species-specific critical thresholds, which we quantify, by data limitations on 3D species distributions as well as by high uncertainty in model O2 projections in equatorial regions. Focus on these topics in future research will strengthen our confidence in assessing climate-change driven losses of contemporary habitat across the global oceans.</p

Reactions of azoalkenes derived from hydrazones of ethyl bromopyruvate with electron rich alkenes and heterocycles

Three hydrazones of ethyl bromopyruvate, the dinitrophenylhydrazone 2a, the toluene-4-sulphonylhydrazone 2b and the t-butoxycarbonylhydrazone 2c, have been reacted with a series of nucleophilic alkenes and heterocycles in the presence of sodium carbonate. Azoalkenes 3 are presumed as intermediates and adducts have been isolated. The azoalkenes derived from hydrazones 2a and 2c are found to be useful electrophiles and electrophilic dienes

How many independent bets are there?

The benefits of portfolio diversification is a central tenet implicit to modern financial theory and practice. Linked to diversification is the notion of breadth. Breadth is correctly thought of as the number of in- dependent bets available to an investor. Conventionally applications us- ing breadth frequently assume only the number of separate bets. There may be a large discrepancy between these two interpretations. We uti- lize a simple singular-value decomposition (SVD) and the Keiser-Gutman stopping criterion to select the integer-valued effective dimensionality of the correlation matrix of returns. In an emerging market such as South African we document an estimated breadth that is considerably lower than anticipated. This lack of diversification may be because of market concentration, exposure to the global commodity cycle and local currency volatility. We discuss some practical extensions to a more statistically correct interpretation of market breadth, and its theoretical implications for both global and domestic investors.Comment: Less technical rewrite. 12 Pages, 6 Figures (.eps