BRIAN (Brain image analysis): A toolkit for the analysis of multimodal brain datasets

The analysis of cognitive processes in man usually involves multiple examina­tion modalities which map different aspects of the brain. Among these proce­dures, at least one modality yielding anatomical information (i.e. MRI*) besidesone or more functional modalities (fMRI, PET, SPECT, EEG, MEG) are involved.Because these different examination methods yield complimentary informationabout the anatomical, metabolical and neurophysiological state of the brain, acombined data evaluation is highly desirable and will lead to results not achiev­able within one examination domain.Such studies are of importance in research (cognitive neuroscience) and ­ withan emphasis on pathological processes ­ in clinical disciplines like neurology,neurosurgery and psychiatry.We have developed a program package for the handling of image datasets(MRI, PET, SPECT, CCT) and signal datasets (EEG, MEG) which allows a com­bined analysis of these data sources in a four­dimensional coordinate space (x, y,z, and time)

Analytical screening of low emissions, high performance duct burners for supersonic cruise aircraft engines

An analytical screening study was conducted to identify duct burner concepts capable of providing low emissions and high performance in advanced supersonic engines. Duct burner configurations ranging from current augmenter technology to advanced concepts such as premix-prevaporized burners were defined. Aerothermal and mechanical design studies provided the basis for screening these configurations using the criteria of emissions, performance, engine compatibility, cost, weight and relative risk. Technology levels derived from recently defined experimental low emissions main burners are required to achieve both low emissions and high performance goals. A configuration based on the Vorbix (Vortex burning and mixing) combustor concept was analytically determined to meet the performance goals and is consistent with the fan duct envelope of a variable cycle engine. The duct burner configuration has a moderate risk level compatible with the schedule of anticipated experimental programs

Highlights in Neutrino and Astroparticle Physics

The main highlights from the papers presented at this workshop are briefly reviewed and discussed in a general context.Comment: 15 pages, 14 Encapsulated Postscript figures, uses espcrc2.sty. Talk given at the Sixth Topical Seminar on Neutrino and Astroparticle Physics, San Miniato, Italy, 17-21 May 199

Modelling mid-Pliocene climate with COSMOS

In this manuscript we describe the experimental procedure employed at the Alfred Wegener Institute in Germany in the preparation of the simulations for the Pliocene Model Intercomparison Project (PlioMIP). We present a description of the utilized Community Earth System Models (COSMOS, version: COSMOS-landveg r2413, 2009) and document the procedures that we applied to transfer the Pliocene Research, Interpretation and Synoptic Mapping (PRISM) Project mid-Pliocene reconstruction into model forcing fields. The model setup and spin-up procedure are described for both the paleo- and preindustrial (PI) time slices of PlioMIP experiments 1 and 2, and general results that depict the performance of our model setup for mid-Pliocene conditions are presented. The mid-Pliocene, as simulated with our COSMOS setup and PRISM boundary conditions, is both warmer and wetter in the global mean than the PI. The globally averaged annual mean surface air temperature in the mid-Pliocene standalone atmosphere (fully coupled atmosphere-ocean) simulation is 17.35 °C (17.82 °C), which implies a warming of 2.23 °C (3.40 °C) relative to the respective PI control simulation

Bach speaks: A cortical "language-network" serves the processing of music

The aim of the present study was the investigation of neural correlates of music processing with fMRI. Chord sequences were presented to the participants, infrequently containing unexpected musical events. These events activated the areas of Broca and Wernicke, the superior temporal sulcus, Heschl's gyrus, both planum polare and planum temporale, as well as the anterior superior insular cortices. Some of these brain structures have previously been shown to be involved in music processing, but the cortical network comprising all these structures has up to now been thought to be domain-specific for language processing. To what extent this network might also be activated by the processing of non-linguistic information has remained unknown. The present fMRI-data reveal that the human brain employs this neuronal network also for the processing of musical information, suggesting that the cortical network known to support language processing is less domain-specific than previously believed

Why are salinity anomalies of great importance for long-term climate variability ? Analysis of simple climate models

We analyze the sensitivity of the ocean’s thermohaline circulation using ideal- ized models of the North Atlantic. The nonlinear Stommel (1961) box model is solved exactly. Using the analytical solution of a coupled atmosphere-ocean version of Stommel’s model, we derive the critical salinity perturbation, nec- essary to induce a break down of the thermohaline circulation . We find that the glacial oceanic circulation with a weaker meridional overturning is more sensitive than the present one. The model reveals furthermore that the optimal perturbation affecting long-term climate variability is by high lat- itude haline forcing, although this perturbation has little resemblence with the most unstable mode of the system and the leading EOF. The linear stage of the forecast error growth is analyzed in the box model. The amplification of the forecast error ellipsoide is largest for high latitude haline forcing, associated with maximum energy growth on times less than a decade. Sensitivity experiments with a more sophisticated coupled model reveal the basic mechanisms involved in the thermohaline circulation’s re- sponse to sea surface salinity perturbations. The results qualitatively agree with those of the analytical model, although different mechanisms are re- sponsible for the sensitivity. Our results are useful for the interpretation of paleoclimatic records and interdecadal climate variability

Characteristics and direct radiative effect of mid-latitude continental aerosols: the ARM case

International audienceA multi-year field measurement analysis of the characteristics and direct radiative effect of aerosols at the Southern Great Plains (SGP) central facility of the Atmospheric Radiation Measurement (ARM) Program is presented. Inter-annual mean and standard deviation of submicrometer scattering fraction (at 550 nm) and Ångström exponent å (450 nm, 700 nm) at the mid-latitude continental site are indicative of the scattering dominance of fine mode aerosol particles, being 0.84±0.03 and 2.25±0.09, respectively. We attribute the diurnal variation of submicron aerosol concentration to coagulation, photochemistry and the evolution of the boundary layer. Precipitation does not seem to play a role in the observed afternoon maximum in aerosol concentration. Submicron aerosol mass at the site peaks in the summer (12.1±6.7mg m-3), with the summer value being twice that in the winter. Of the chemically analyzed ionic components (which exclude carbonaceous aerosols), SO4= and NH4+ constitute the dominant species at the SGP seasonally, contributing 23-30% and 9-12% of the submicron aerosol mass, respectively. Although a minor species, there is a notable rise in NO3- mass fraction in winter. We contrast the optical properties of dust and smoke haze. The single scattering albedo w0 shows the most remarkable distinction between the two aerosol constituents. We also present aircraft measurements of vertical profiles of aerosol optical properties at the site. Annually, the lowest 1.2 km contributes 70% to the column total light scattering coefficient. Column-averaged and surface annual mean values of hemispheric backscatter fraction (at 550 nm), w0 (at 550 nm) and å (450 nm, 700 nm) agree to within 5% in 2001. Aerosols produce a net cooling (most pronounced in the spring) at the ARM sit