3,030 research outputs found

    Expert Witness and the Proof of Foreign Law

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    No evidence for altered prenatal exposure to testosterone in young females diagnosed with Borderline Personality Disorder

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    Introduction. Borderline Personality Disorder (BPD) is characterised, among other features, by in- creased impulsivity and aggression, both directed toward the self and others. These clinical signs most likely arise from complex gene-environment interactions. In our study, we sought to elucidate the role of prenatal testosterone exposure in female patients with BPD. Materials and Methods. In a sample of 42 patients and 50 controls matched for age and biological sex, we measured the ratio of the second to the fourth digit of both hands (2D:4D ratio), which is established as a reliable correlate of prenatal testosterone levels in the foetus. In addition, we used sev- eral self-rating scales to determine personality dimensions, impulsivity, aggressiveness and risk-taking behaviour. Results. No differences between the groups emerged with regard to 2D:4D ratio of both hands. In ad- dition, there were almost no correlations between psychological measures and the 2D:4D ratio in the entire sample. Conclusions. Contrary to predictions, female patients with BPD did not differ from controls in 2D:4D ratio bimanually, suggesting no abnormal intrauterine (prenatal) exposure to testosterone in this clinical group. As expected, differences between patients and controls in personality traits, impul- sivity, aggressiveness and risk-taking were highly significant and in concordance with the existing body of knowledge. Since BPD features are highly heterogeneous, it could be interesting to study subgroups of BPD patients, rather than the broader phenotype according to DSM-5 criteria

    No evidence for altered prenatal exposure to testosterone in young females diagnosed with Borderline Personality Disorder

    Get PDF
    Introduction. Borderline Personality Disorder (BPD) is characterised, among other features, by in- creased impulsivity and aggression, both directed toward the self and others. These clinical signs most likely arise from complex gene-environment interactions. In our study, we sought to elucidate the role of prenatal testosterone exposure in female patients with BPD. Materials and Methods. In a sample of 42 patients and 50 controls matched for age and biological sex, we measured the ratio of the second to the fourth digit of both hands (2D:4D ratio), which is established as a reliable correlate of prenatal testosterone levels in the foetus. In addition, we used sev- eral self-rating scales to determine personality dimensions, impulsivity, aggressiveness and risk-taking behaviour. Results. No differences between the groups emerged with regard to 2D:4D ratio of both hands. In ad- dition, there were almost no correlations between psychological measures and the 2D:4D ratio in the entire sample. Conclusions. Contrary to predictions, female patients with BPD did not differ from controls in 2D:4D ratio bimanually, suggesting no abnormal intrauterine (prenatal) exposure to testosterone in this clinical group. As expected, differences between patients and controls in personality traits, impul- sivity, aggressiveness and risk-taking were highly significant and in concordance with the existing body of knowledge. Since BPD features are highly heterogeneous, it could be interesting to study subgroups of BPD patients, rather than the broader phenotype according to DSM-5 criteria

    A Persistent Simulation Environment for Autonomous Systems

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    The age of Autonomous Unmanned Aircraft Systems (AUAS) is creating new challenges for the accreditation and certification requiring new standards, policies and procedures that sanction whether a UAS is safe to fly. Establishing a basis for certification of autonomous systems via research into trust and trustworthiness is the focus of Autonomy Teaming and TRAjectories for Complex Trusted Operational Reliability (ATTRACTOR), a new NASA Convergent Aeronautics Solution (CAS) project. Simulation Environments to test and evaluate AUAS decision making may be a low-cost solution to help certify that various AUAS systems are trustworthy enough to be allowed to fly in current general and commercial aviation airspace. NASA is working to build a peer-to-peer persistent simulation (P3 Sim) environment. The P3 Sim will be a Massively Multiplayer Online (MMO) environment were AUAS avatars can interact with a complex dynamic environment and each other. The focus of the effort is to provide AUAS researchers a low-cost intuitive testing environment that will aid training for and assessment of decisions made by autonomous systems such as AUAS. This presentation focuses on the design approach and challenges faced in development of the P3 Sim Environment is support of investigating trustworthiness of autonomous systems

    Poker as a Domain of Expertise

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    Poker is a game of skill and chance involving economic decision-making under uncertainty. It is also a complex but well-defined real-world environment with a clear rule-structure. As such, poker has strong potential as a model system for studying high-stakes, high-risk expert performance. Poker has been increasingly used as a tool to study decision-making and learning, as well as emotion self-regulation. In this review, we discuss how these studies have begun to inform us about the interaction between emotions and technical skill, and how expertise develops and depends on these two factors. Expertise in poker critically requires both mastery of the technical aspects of the game, and proficiency in emotion regulation; poker thus offers a good environment for studying these skills in controlled experimental settings of high external validity.We conclude by suggesting ideas for future research on expertise, with new insights provided by poker.Peer reviewe

    Urethane polythioether self-crosslinking resins

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    A straightforward methodology for the synthesis of polythioether resins and resulting coatings was elaborated. The resins were produced via radical stepwise polyaddition of functional bisalkene and bisthiol monomers to yield self-crosslinkable polythioethers, which can be formulated as one-component systems. The thermal curing of these self-crosslinking resins is enabled by the presence of both hydroxyl and blocked isocyanate moieties, thereby resulting in the formation of a urethane polythioether network. Furthermore, the presence of the thioether functions offered the opportunity to alter thermal and mechanical properties by oxidation into sulfoxide or sulfone linkages, resulting in polysulfoxide and -sulfone containing coatings. Thiol-ene chemistry in combination with blocked isocyanate chemistry provides a new platform for functional urethane- and sulfide-containing coatings, which can be tailored to a wide variety of applications

    Fundamental Understanding of Rotor Aeromechanics at High Advance Ratio Through Wind Tunnel Testing

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    The purpose of this research is to further the understanding of rotor aeromechanics at advance ratios (mu) beyond the maximum of 0.5 (ratio of forward airspeed to rotor tip speed) for conventional helicopters. High advance ratio rotors have applications in high speed compound helicopters. In addition to one or more conventional main rotors, these aircraft employ either thrust compounding (propellers), lift compounding (fixed-wings), or both. An articulated 4-bladed model rotor was constructed, instrumented, and tested up to a maximum advance ratio of mu=1.6 in the Glenn L. Martin Wind Tunnel at the University of Maryland. The data set includes steady and unsteady rotor hub forces and moments, blade structural loads, blade flapping angles, swashplate control angles, and unsteady blade pressures. A collective-thrust control reversal---where increasing collective pitch results in lower rotor thrust---was observed and is a unique phenomenon to the high advance ratio flight regime. The thrust reversal is explained in a physical manner as well as through an analytical formulation. The requirements for the occurrence of the thrust reversal are enumerated. The effects of rotor geometry design on the thrust reversal onset are explored through the formulation and compared to the measured data. Reverse-flow dynamic stall was observed to extend the the lifting capability of the edgewise rotor well beyond the expected static stall behavior of the airfoil sections. Through embedded unsteady blade surface pressure transducers, the normal force, pitching moment, and shed dynamic stall vortex time histories at a blade section in strong reverse flow were analyzed. Favorable comparisons with published 2-D pitching airfoil reverse flow dynamic stall data indicate that the 3-D stall environment can likely be predicted using models developed from such 2-D experiments. Vibratory hub loads were observed to increase with advance ratio. Maximum amplitude was observed near mu=1, with a reduction in vibratory loads at higher advance ratios. Blade load 4/rev harmonics dominated due to operation near a 4/rev fanplot crossing of the 2nd flap bending mode natural frequency. Oscillatory loads sharply increase in the presence of retreating blade reverse flow dynamic stall, and are evident in blade torsion, pitch link, and hub load measurements. The blades exhibited torsion moment vibrations at the frequency of the 1st torsion mode in response to the reverse flow pitching moment loading

    Developing World Users as Lead Users: A Case Study in Engineering Reverse Innovation

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    This paper examines the “reverse innovation” of the leveraged freedom chair (LFC), a high-performance, low-cost, off-road wheelchair originally designed for developing countries. A needs study of 71 developed world wheelchair users was conducted through three different data collection efforts. These data were contrasted with studies of 125 developing world wheelchair users, who were shown to be lead users for their developed world counterparts. The GRIT freedom chair (GFC), the developed world version of the LFC, was designed based on results of the study. By recognizing developing country users as lead users, designers can reveal latent needs and create globally disruptive innovations.Singapore University of Technology and DesignMassachusetts Institute of Technology. Department of Mechanical EngineeringRobert N. Noyce Career Development Chair at MITGlobal Research Innovation and Technology (GRIT
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