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De Bruyn M.,Bangor University | Stelbrink B.,Humboldt University of Berlin | Morley R.J.,Royal Holloway, University of London | Morley R.J.,Palynova Ltd | And 15 more authors.
Systematic Biology

Tropical Southeast (SE) Asia harbors extraordinary species richness and in its entirety comprises four of the Earth's 34 biodiversity hotspots. Here, we examine the assembly of the SE Asian biota through time and space. We conduct meta-analyses of geological, climatic, and biological (including 61 phylogenetic) data sets to test which areas have been the sources of long-term biological diversity in SE Asia, particularly in the pre-Miocene, Miocene, and Plio-Pleistocene, and whether the respective biota have been dominated by in situ diversification, immigration and/or emigration, or equilibrium dynamics. We identify Borneo and Indochina, in particular, as major "evolutionary hotspots" for a diverse range of fauna and flora. Although most of the region's biodiversity is a result of both the accumulation of immigrants and in situ diversification, within-area diversification and subsequent emigration have been the predominant signals characterizing Indochina and Borneo's biota since at least the early Miocene. In contrast, colonization events are comparatively rare from younger volcanically active emergent islands such as Java, which show increased levels of immigration events. Few dispersal events were observed across the major biogeographic barrier of Wallace's Line. Accelerated efforts to conserve Borneo's flora and fauna in particular, currently housing the highest levels of SE Asian plant and mammal species richness, are critically required. © The Author(s) 2014. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. Source

Hardin E.E.,University of Tennessee | Longhurst M.O.,Texas Technology University
Journal of Counseling Psychology

Despite robust support for the basic theoretical model of social cognitive career theory (Lent, Brown, & Hackett, 1994) and predictions that, for example, increases (or declines) in self-efficacy would lead to subsequent increases (or declines) in interest, there has been surprisingly little longitudinal research that has directly examined the extent to which members of different groups (e.g., women and men) actually do experience changes in critical social- cognitive variables over time early in their curricula in the fields of science, technology, engineering, and mathematics (STEM). Knowing the extent to which such changes occur in typical introductory undergraduate courses is important for targeting interventions to increase persistence of underrepresented groups in STEM. We measured social-cognitive-career-theoryrelevant variables near the middle and at the end of the 1st semester of a gateway introductory chemistry course and found that women had lower STEM self-efficacy, coping self-efficacy, and STEM interest than did men, even after controlling for actual course performance. Although there were no detrimental changes across the semester for women or men, men experienced a small but significant increase in their perceived support for pursuing a STEM degree, whereas women did not. © 2015 American Psychological Association. Source

Maithripala D.H.S.,University of Peradeniya | Berg J.M.,Texas Technology University

This paper shows how "integral action" may be implemented intrinsically in the general setting of fully-actuated mechanical systems on Lie groups. When combined with an intrinsic formulation of PD control, integral action ensures that a suitably defined configuration tracking error will converge to zero in response to constant velocity commands and disturbance forces. Convergence is locally exponential and almost global, and is robust to bounded parametric uncertainty. For more general bounded commands and disturbances, the tracking error can be made arbitrarily small by choosing sufficiently large controller gains. A separation principle allows the addition of an intrinsic velocity observer to complete a geometric analog to the familiar output feedback PID controller for second-order linear systems. The controller extends naturally to accommodate tracking of equivariant output functions. The result is explicitly shown for the Lie group SO(3), and supported by simulations of a 6DOF quadrotor model. © 2015 Elsevier Ltd. Source

Hamilton K.R.,University of Maryland University College | Littlefield A.K.,Texas Technology University | Anastasio N.C.,University of Texas Medical Branch | Cunningham K.A.,University of Texas Medical Branch | And 10 more authors.
Personality Disorders: Theory, Research, and Treatment

Impulsivity is a multifaceted construct that is a core feature of multiple psychiatric conditions and personality disorders. However, progress in understanding and treating impulsivity is limited by a lack of precision and consistency in its definition and assessment. Rapid-response impulsivity (RRI) represents a tendency toward immediate action that occurs with diminished forethought and is out of context with the present demands of the environment. Experts from the International Society for Research on Impulsivity (InSRI) met to discuss and evaluate RRI measures in terms of reliability, sensitivity, and validity, with the goal of helping researchers and clinicians make informed decisions about the use and interpretation of findings from RRI measures. Their recommendations are described in this article. Commonly used clinical and preclinical RRI tasks are described, and considerations are provided to guide task selection. Tasks measuring two conceptually and neurobiologically distinct types of RRI, "refraining from action initiation" (RAI) and "stopping an ongoing action" (SOA) are described. RAI and SOA tasks capture distinct aspects of RRI that may relate to distinct clinical outcomes. The InSRI group recommends that (a) selection of RRI measures should be informed by careful consideration of the strengths, limitations, and practical considerations of the available measures; (b) researchers use both RAI and SOA tasks in RRI studies to allow for direct comparison of RRI types and examination of their associations with clinically relevant measures; and (c) similar considerations be made for human and nonhuman studies in an effort to harmonize and integrate preclinical and clinical research. © 2015 American Psychological Association. Source

Reid R.C.,University of California at Los Angeles | Garos S.,Texas Technology University | Fong T.,University of California at Los Angeles
Journal of Behavioral Addictions

Background and aims: The past decade has seen an increased interest in understanding hypersexual behavior and its associated features. Beyond the obvious risks for sexually transmitted infections, there is a paucity of literature examining specific challenges encountered by hypersexual individuals. This study investigated and developed a new scale, the Hypersexual Behavior Consequences Scale (HBCS), to assess the various consequences reported among hypersexual patients. Methods: Participants were drawn from a sample of patients recruited in a DSM-5 Field Trial for Hypersexual Disorder (HD). Participants completed the Hypersexual Behavior Inventory, a structured diagnostic interview to assess for psychopathology and HD, and self-report measures of personality, life satisfaction, and the initial item pool for the HBCS. Results: Factor analysis reduced the HBCS items to a single factor solution which showed high internal consistency and stability over time. Higher HBCS scores were positively correlated with higher levels of emotional dysregulation, impulsivity, and stress proneness and lower levels of satisfaction with life and happiness. HBCS scores among the hypersexual patients were significantly higher than non-hypersexual patients. Conclusions: The HBCS possesses good psychometric properties and appears to capture various consequences associated with the DSM-5 proposed criteria for HD. The HBCS can be used to aid clinicians and researchers in identifying consequences associated with hypersexual behavior. The HBCS may also prove a useful tool to guide treatment interventions aimed at reducing the negative impact of hypersexuality in patient populations. © 2012 Akadémiai Kiadó. Source

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