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Individual differences in the neuropsychopathology of addiction.
Drug addiction or substance-use disorder is a chronically relapsing disorder that progresses through binge/intoxication, withdrawal/negative affect and preoccupation/anticipation stages. These stages represent diverse neurobiological mechanisms that are differentially involved in the transition from recreational to compulsive drug use and from positive to negative reinforcement. The progression from recreational to compulsive substance use is associated with downregulation of the brain reward systems and upregulation of the brain stress systems. Individual differences in the neurobiological systems that underlie the processing of reward, incentive salience, habits, stress, pain, and executive function may explain (i) the vulnerability to substance-use disorder; (ii) the diversity of emotional, motivational, and cognitive profiles of individuals with substance-use disorders; and (iii) heterogeneous responses to cognitive and pharmacological treatments. Characterization of the neuropsychological mechanisms that underlie individual differences in addiction-like behaviors is the key to understanding the mechanisms of addiction and development of personalized pharmacotherapy
Comparison of closed loop model with flight test results
An analytic technique capable of predicting the landing characteristics of proposed aircraft configurations in the early stages of design was developed. In this analysis, a linear pilot-aircraft closed loop model was evaluated using experimental data generated with the NT-33 variable stability in-flight simulator. The pilot dynamics are modeled as inner and outer servo loop closures around aircraft pitch attitude, and altitude rate-of-change respectively. The landing flare maneuver is of particular interest as recent experience with military and other highly augmented vehicles shows this task to be relatively demanding, and potentially a critical design point. A unique feature of the pilot model is the incorporation of an internal model of the pilot's desired flight path for the flare maneuver
Metallic composites as high-temperature fasteners
Metallic composities can be fabricated in one-step process in which mixture is directionally solidified. Phase-reinforced eutectic alloys have superior high-temperature mechanical properties
Go with the Flow, Average Holographic Universe
Gravity is a macroscopic manifestation of a microscopic quantum theory of
space-time, just as the theories of elasticity and hydrodynamics are the
macroscopic manifestation of the underlying quantum theory of atoms. The
connection of gravitation and thermodynamics is long and deep. The observation
that space-time has a temperature for accelerating observers and horizons is
direct evidence that there are underlying microscopic degrees of freedom. The
equipartition of energy, meaning of temperature, in these modes leads one to
anticipate that there is also an entropy associated. When this entropy is
maximized on a volume of space-time, then one retrieves the metric of
space-time (i.e. the equations of gravity, e.g. GR). Since the metric satisfies
the extremum in entropy on the volume, then the volume integral of the entropy
can readily be converted to surface integral, via Gauss's Theorem. This surface
integral is simply an integral of the macroscopic entropy flow producing the
mean entropy holographic principle. This approach also has the added value that
it naturally dispenses with the cosmological constant/vacuum energy problem in
gravity except perhaps for second order quantum effects on the mean surface
entropy.Comment: 14 page
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