Anxiety and Posttraumatic Stress Disorder in the Context of Human Brain Evolution:A Role for Theory in DSM-V?

The “hypervigilance, escape, struggle, tonic immobility”\ud evolutionarily hardwired acute peritraumatic response\ud sequence is important for clinicians to understand. Our\ud commentary supplements the useful article on human\ud tonic immobility (TI) by Marx, Forsyth, Gallup, Fusé and Lexington (2008). A hallmark sign of TI is peritraumatic\ud tachycardia, which others have documented as a\ud major risk factor for subsequent posttraumatic stress\ud disorder (PTSD). TI is evolutionarily highly conserved\ud (uniform across species) and underscores the need for\ud DSM-V planners to consider the inclusion of evolution\ud theory in the reconceptualization of anxiety and PTSD.\ud We discuss the relevance of evolution theory to the\ud DSM-V reconceptualization of acute dissociativeconversion\ud symptoms and of epidemic sociogenic disorder(epidemic “hysteria”). Both are especially in need of attention in light of the increasing threat of terrorism\ud against civilians. We provide other pertinent examples.\ud Finally, evolution theory is not ideology driven (and\ud makes testable predictions regarding etiology in “both\ud directions”). For instance, it predicted the unexpected\ud finding that some disorders conceptualized in DSM-IV-TR as innate phobias are conditioned responses and thus better conceptualized as mild forms of PTSD. Evolution\ud theory may offer a conceptual framework in\ud DSM-V both for treatment and for research on psychopathology.\u

Dracula and the Afterlife: A Psychological Explanation

Until relatively recently, the primary psychological approach to understanding Bram Stoker’s Dracula and the folklore of vampires has been psychoanalysis. Maurice Richardson asserted in 1956 that Dracula must be seen from a Freudian standpoint, since “from no other does the story really make any sense” (427). However, the psychoanalytic approach shares little with modern, scientifically based psychology. Fascinating though it may be, psychoanalytic theory has almost no measurable attributes and may itself be as mythical as vampires and an afterlife. Rather, psychoanalysis is a creative theory of human cognition and behavior that can be neither proven false, objectively replicated, nor used to predict novel, testable insights. As Clive Leatherdale, having presented such a reading of Dracula, concedes, “psychoanalysis has been to some extent dismissed as a literary fad whose time has come and gone” (190 n1). This paper presents an alternative psychological theory that explains how vampirism has captured the imagination of so many people in so many cultures. This theory is called Existential Projection to an Afterlife (EPA) and it incorporates a number of well-studied psychological factors: Object constancy, generalization, fear and conditioning. Some background is needed to see how EPA theory provides a psychological mechanism for humans to reduce existential terror when contemplating death, i.e., nonexistence of the self and nothingness. Fear is reduced by the comforting illusion of an afterlife. Leatherdale states that “The concept of the vampire is founded upon two precepts: the belief in life after death, and the magical power of blood” (13). This paper will address both precepts, but with the major focus on the psychology of belief in life after death. Neither belief in vampires nor belief in an afterlife has any basis in objectively observed fact, yet belief in an afterlife is essentially universal in human society and belief in vampires is well established in the folklore of many cultures. The former is related to a deep need to perpetuate the self when the body dies, the latter to a method of doing so. The notion of an afterlife is linked to concepts of religion, God, good and evil, and while not all are related directly to EPA theory, this paper will touch upon those links

Parametric studies of advanced turboprops

The effects of geometric variables (sweep and twist) on the structural performance of advanced turboprops are investigated. The investigation is limited to aerodynamically efficient turboprops using an acceptable design configuration as a baseline. The baseline configuration is modified using a seven by seven array of independently varying sweep and twist parameters while maintaining acceptable aerodynamic efficiency. The turboprop structural performance is evaluated in terms of critical speeds, tip displacements, and vibration frequencies where geometric nonlinearities are included. The results obtained are presented in such a manner as to highlight the effects of sweep and twist on the structural performance of aerodynamically efficient turboprop configurations

A versatile source of polarization-entangled photons

We propose a method for the generation of a large variety of entangled states, encoded in the polarization degrees of freedom of N photons, within the same experimental setup. Starting with uncorrelated photons, emitted from N arbitrary single photon sources, and using linear optical tools only, we demonstrate the creation of all symmetric states, e.g., GHZ- and W-states, as well as all symmetric and non-symmetric total angular momentum eigenstates of the N qubit compound.Comment: 4 pages, 3 figure

Takagi-Taupin Description of X-ray Dynamical Diffraction from Diffractive Optics with Large Numerical Aperture

We present a formalism of x-ray dynamical diffraction from volume diffractive optics with large numerical aperture and high aspect ratio, in an analogy to the Takagi-Taupin equations for strained single crystals. We derive a set of basic equations for dynamical diffraction from volume diffractive optics, which enable us to study the focusing property of these optics with various grating profiles. We study volume diffractive optics that satisfy the Bragg condition to various degrees, namely flat, tilted and wedged geometries, and derive the curved geometries required for ultimate focusing. We show that the curved geometries satisfy the Bragg condition everywhere and phase requirement for point focusing, and effectively focus hard x-rays to a scale close to the wavelength.Comment: 18 pages, 12 figure

Characterization of Sugar Diversity in Floral and Extra-Floral Nectar from the Coastal Coral Tree (Erythrina caffra Thunb.) in Southern California

The Coastal Coral Tree (Erythrina caffra Thunb.) produces floral nectar (FN) that serves to attract pollinating insects, but also secretes nectar from extra-floral (EFN) glands that serves to at-tract predatory insects, such as ants. While stu-dies on myrmecophytes (i.e. specialized plants that attract and interact with ants) have primarily focused on interspecific evaluations of EFN chemistry, the Coastal Coral tree offers an op-portunity to contrast intraspecific nectar chemi-stry with differing evolutionary and ecological functions. We hypothesized that the richness of (molecular) sugar species, relative concentra-tions, and diversity of sugars in FN and foliar EFN would diverge due to differences in the ecological role of the two types of nectar. High performance liquid chromatography with refrac-tive index detection was used to identify the richness of sugar species (based on retention time), measure the relative concentrations, and evaluate the diversity of sugars in FN and foliar EFN secretions. We detected sugar species unique to each gland type and reported signifi-cant differences in the relative concentration of one sugar species common to both gland types. While the mean diversity index of sugars was similar for both gland types, the diversity of fo-liar EFN sugars was significantly more variable than that of FN sugars. The composition of FN showed little variation, and was reflective of its fundamental role in plant reproduction. Foliar EFN, however, demonstrated the variability ex-pected of a context-dependent myrmecophyte that interacts with a facultative ant species as-semblage across a mosaic of abiotic and biotic conditions