The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

The semantic layers of Timber

We present a three-layered semantics of Timber, a language designed for programming real-time systems in a reactive, object-oriented style. The innermost layer amounts to a traditional deterministic, pure, functional language, around which we formulate a middle layer of concurrent objects, in terms of a monadic transition semantics. The outermost layer, where the language is married to deadline-driven scheduling theory, is where we define message ordering and CPU allocation to actions. Our main contributions are a formalized notion of a time-constrained reaction, and a demonstration of how scheduling theory, process calculii, and the lambda calculus can be jointly applied to obtain a direct and succinct semantics of a complex, real-world programming language with well-defined real-time behavior.Validerad; 2003; 20070227 (ysko

Report on the Programming Language

ions : : : : : : : : : : : : : : : : 12 3.3 Operator Applications : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 13 3.4 Sections : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 13 3.5 Conditionals : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 14 3.6 Lists : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 14 3.7 Tuples : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 14 3.8 Unit Expressions and Parenthesised Expressions : : : : : : : : : : : : : : : 15 3.9 Arithmetic Sequences : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 15 3.10 List Comprehensions : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 16 3.11 Let Expressions : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 16 3.12 Case Expressions : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 17 3.13 Expression Type-Signatures : : : : : : : : : : : : :..

State-Dependent Riccati Equation Control Of A Small Unmanned Helicopter

This paper is an initial report on flight experiments with a small, unmanned helicopter using a state dependent Riccati Equation (SDRE) controller for autonomous, agile maneuvering. The control design is based upon a full, 6-DoF, analytic nonlinear dynamic model, which is manipulated into a pseudo-linear form in which system matrices are given explicitly as a function of the current state. A standard Riccati equation is then solved numerically in each frame of a 50 Hz. control loop to design the state feedback control law on-line. Several flights have been flown with the helicopter to evaluate the accuracy of tracking under SDRE control in comparison with simulation results. NOMENCLATURE 235 vehicle velocities in longitudinal, vehicle angular (roll, pitch and yaw) velocities Euler angles (roll, pitch and yaw) vehicle position in inertial frame !#"% longitudinal and lateral cyclic control inputs '&()* +&( main rotor collective and tail rotor collective control inputs ,- 3508-2 wind velocities in longitudinal, helicopter mass 24353 24646 2877 moments of inertia around rolling, pitching and yawing axes main rotor thrust $ tail rotor thrust =?> rotor thrust coefficient @BA inflow ratio advance ratio normal airflow component D!E :<; main rotor induced velocity D EGF speed of the rotor blade tip H air density I :<; main rotor disk area main rotor blade lift curve slope Senior Research Associate, AIAA member L Senior Research Associate M Research Engineer N Senior Engineer Professor P Graduate Research Assistant KK Associate Professor, AIAA member rotor solidity ratio R , coeff. of non-ideal wake contraction ITS5UWV 3 frontal fuselage drag area main r..