Military Veteran Students Transition to Academic Life with PTSD, Trauma, and Potential for Freezing Response.

The current study is the first known research to investigate the association of the freezing response with PTSD and traumatic stress in the military veteran student population. Current understanding of the freezing response are primarily based in comparative psychology, with some studies extending to human participants (Azevedo et al., 2005; Facchinetti et al., 2006; Hagenaars et al., 2012; Volchan et al., 2017). Models generally agree that the freezing response consists of reduced body sway with decreased heart rate (Porges, 2003, 2007; Hagenaars et al., 2014). Thirty-eight military veteran students (n=38; 18 female; 20 male) with ages ranged from 19 to 49 participated in the study. Participants completed self-report assessments administered through Qualtrics, which include the PTSD Checklist (PCL-5; Weathers et al., 2013), Brief Trauma Questionnaire (BTQ; Schnurr et al., 1999), and additional demographic, health, and military questions. To objectively measure the freezing response, participants stood on a stabilometric platform (Tekscan Inc., South Boston, MA) with a heart rate variability (HRV) monitor attached. Participants then completed four 60-second trials. The first trial was a baseline with eyes open, followed by three trials of randomized emotional stimuli of neutral, pleasant, and unpleasant images from the International Affective Picture System (IAPS; Lang et al., 1997). Results reveal evidence of a freezing response that includes reduced body sway and bradycardia when veteran students are presented with imminent threat in the form of unpleasant stimulus. Participants with severe PTSD symptomology and a history of traumatic events measured a freezing response across all emotional stimuli except the unpleasant stimulus where they had an avoidant response. This may indicate the cumulative effect of traumatic life events on the defense system. This study contributes to the body of knowledge on the freezing response in humans that indicates an increased risk for the development of PTSD and increased severity of symptoms. Keywords: PTSD, traumatic life events, military veterans, university students, stress response, fear response, freezing, avoidance, tonic immobility, body sway, heart rate, posturography, stabilometer, stress, traum

The congenital and see-saw nystagmus in the prototypical achiasma of canines: comparison to the human achiasmatic prototype

AbstractWe applied new methods for canine eye-movement recording to the study of achiasmatic mutant Belgian Sheepdogs, documenting their nystagmus waveforms and comparing them to humans with either congenital nystagmus (CN) alone or in conjunction with achiasma. A sling apparatus with head restraints and infrared reflection with either earth- or head-mounted sensors were used. Data were digitized for later evaluation. The horizontal nystagmus (1–6 Hz) was similar to that of human CN. Uniocular and disconjugate nystagmus and saccades were recorded. See-saw nystagmus (SSN), not normally seen with human CN, was present in all mutants (0.5–6 Hz) and in the one human achiasmat studied thus far. This pedigree is an animal model of CN and the SSN caused by achiasma or uniocular decussation. Given the finding of SSN in all mutant dogs and in a human, achiasma may be sufficient for the development of congenital SSN and, in human infants, SSN should alert the clinician to the possibility of either achiasma or uniocular decussation. Finally, the interplay of conjugacy and disconjugacy suggests independent ocular motor control of each eye with variable yoking in the dog

Facilitators and Pitfalls in the Use of Consultation Strategies : Prospective Special Educators’ Self-Reflections on Audio-recorded Consultation Sessions

acceptedVersio

Modification of streaming potential by precipitation of calcite in a sand-water system: laboratory measurements pH range from 4 to 12

Spontaneous Potentials associated with volcanic activity are often interpreted by means of the electrokinetic potential, which is usually positive in the flow direction (i.e. Zeta potential of the rock is negative). The water-rock interactions in hydrothermal zones alter the primary minerals leading to the formation of secondary minerals. This work addresses the study of calcite precipitation in a sand composed of 98% quartz and 2% calcite using streaming potential measurements. The precipitation of calcite as a secondary mineral phase, inferred by high calcite saturation indices and by a fall in permeability, has a significant effect on the electrokinetic behaviour, leading to a significant reduction in the Zeta potential (in absolute value) and even a change in sign. The measured decrease in Zeta potential from -16 mV to -27±4 mV takes place as the pH rises from 4 to 7, while it remains constant at -25±1 mV as the pH increases from 8 to 10.5. For pH higher than 10.5, calcite precipitates and is expected to coat the quartz surface. The measured Zeta potential vary from -17 to +8 mV for pH ranging from 10.6 to 11.7 depending on the amount of precipitated calcite indicated by the decrease in permeability. The observed change in sign of the electrical surface potential rules out the usual qualitative interpretation of SP anomalies in order to determine fluid circulations, even at pH lower than 9 if calcite is widely present as a secondary mineral phase, since the electrical surface potential of calcite depends also on CO2 partial pressure and [Ca2+]. Therefore SP anomalies as measured in hydrothermal field, without mineralogical analyses of hydrothermal deposits, and without geochemical fluid survey, should be interpreted with caution.Comment: The definitive version is available at www.blackwell-synergy.com; We acknowledge the Geophysical Journal International, the Royal Astronomical Society and Blackwell Publishing. Full bibliographic reference is : Guichet, X., L. Jouniaux, and N. Catel, Modification of streaming potential by precipitation of calcite in a sand-water system: laboratory measurements in the pH range from 4 to 12, Geophysical Journal International, 166, 445-460, doi:10.1111/j.1365-246X.2006.02922.x, 200

Keep them alive! Design and Evaluation of the “Community Fostering Reference Model”

Firms host online communities for commercial purposes, for example in order to integrate customers into ideation for new product development. The success of these firm-hosted online communities depends entirely on the cooperation of a high number of customers that constantly produce valuable knowledge for firms. However, in practice, the majority of successfully implemented communities suffers from stagnation and even a decrease of member activities over time. Literature provides numerous guidelines on how to build and launch these online communities. While these models describe the initial steps of acquiring and activating a community base from scratch very well and explicitly, they neglect continuous member activation and acquistion after a successful launch. Against this background, the authors propose the Community Fostering Reference Model (CoFoRM), which represents a set of general procedures and instruments to continuously foster member activity. In this paper, the authors present the theory-driven design as well as the evaluation of the CoFoRM in a practical use setting. The evaluation results reveal that the CoFoRM represents a valuable instrument in the daily working routine of community managers, since it efficiently helps activating community members especially in the late phases of a community’s LifeCycle