Auditory nerve fibers encode sounds in the precise timing of action potentials (APs), which is used for such computations as sound localization. Timing information is relayed through several cell types in the auditory brainstem that share an unusual property: their APs are not overshooting, suggesting that the cells have very low somatic sodium conductance (g Na ). However, it is not clear how g Na influences temporal precision. We addressed this by comparing bushy cells (BCs) in the mouse cochlear nucleus with T-stellate cells (SCs), which do have normal overshooting APs. BCs play a central role in both relaying and refining precise timing information from the auditory nerve, whereas SCs discard precise timing information and encode the envelope of sound amplitude. Nucleated-patch recording at nearphysiological temperature indicated that the Na current density was 62% lower in BCs, and the voltage dependence of g Na inactivation was 13 mV hyperpolarized compared with SCs. We endowed BCs with SC-like g Na using two-electrode dynamic clamp and found that synaptic activity at physiologically relevant rates elicited APs with significantly lower probability, through increased activation of delayed rectifier channels. In addition, for two near-simultaneous synaptic inputs, the window of coincidence detection widened significantly with increasing g Na , indicating that refinement of temporal information by BCs is degraded by g Na . Thus, reduced somatic g Na appears to be an adaption for enhancing fidelity and precision in time-coding neurons.

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This paper investigates the psychological traits of individuals' attraction to engaging in hacking behaviors (both ethical and illegal/unethical) upon entering the workforce. We examine the role of the Dark Triad, Opposition to Authority and Thrill-Seeking traits as regards the propensity of an individual to be interested in White Hat, Black Hat, and Grey Hat hacking. A new set of scales were developed to assist in the delineation of the three hat categories. We also developed a scale to measure each subject's perception of the probability of being apprehended for violating privacy laws. Engaging in criminal activity involves a choice where there are consequences and opportunities, and individuals perceive them differently, but they can be deterred if there is a likelihood of punishment, and the punishment is severe. The results suggest that individuals that are White Hat, Grey Hat and Black Hat hackers score high on the Machiavellian and Psychopathy scales. We also found evidence that Grey Hatters oppose authority, Black Hatters score high on the thrill-seeking dimension and White Hatters, the good guys, tend to be Narcissists. Thrill-seeking was moderately important for White Hat hacking and Black hat hacking. Opposition to Authority was important for Grey Hat hacking. Narcissism was not statistically significant in any of the models. The probability of being apprehended had a negative effect on Grey Hat and Black Hat hacking.

Approved for public release; distribution unlimited. Prepared for r EUSTIS DIRECTORATE U. S. ARMY AIR MOBILITY RESEARCH AND DEVELOPMENT LABORATORY __Fort Eustis, Va. 23604 cm, all EUSTIS DIRECTORATE POSITION STATEMENT This report provides detailed insight into a specific R&D problem experienced during the Dynamic System Test Rig (DSTR) phase of the HLH program. A discussion of the evolution of the problem, details of the subsequent design investigation, and the resulting solution are presented. Results of this contract are being integrated with other R&D problem identification efforts at the Eustis Directorate to establish research and development programs to improve engine/drive train/airframe dynamic interface characteristics of future Army aircraft systems. Mr. Allen C. Royal, Propulsion Technical Area, Technology Applications Divis' served as Project Engineer for this effort.