Composite Propellant Based on a New Nitrate Ester

Composite propellants based on the solid nitrate ester 2,3‐hydroxymethyl‐2,3‐dinitro‐1,4‐butanediol tetranitrate (SMX) were theoretically and experimentally examined and compared to formulations based on ammonium perchlorate (AP). Thermochemical equilibrium calculations show that aluminized SMX‐based formulations can achieve theoretical sea level specific impulse values upwards of 260 s. Both ignition sensitivity (tested via drop weight impact, electrostatic discharge, and BAM friction) and physical properties (hardness and thermal properties) are comparable to those of the AP‐based formulations. However, the SMX‐based formulation could be detonated using a high explosive donor charge in contact with the propellant. Differential scanning calorimetry of the SMX‐based propellant indicated an exotherm onset of 140 °C, which corresponds to the known decomposition temperature of SMX. The propellant has a high burning rate of 1.57 cm s⁻¹ at 6.89 MPa, with a pressure exponent of 0.85. This high pressure sensitivity might be addressed using various energetic and/or stabilizing additives. With good performance and high density, SMX‐based composite propellants may offer a promising perchlorate‐free alternative to existing AP‐based formulations.     

Circulating Tumor Cells (CTC) and Cell-Free DNA (cfDNA) Workshop 2016: Scientific Opportunities and Logistics for Cancer Clinical Trial Incorporation

Despite the identification of circulating tumor cells (CTCs) and cell-free DNA (cfDNA) as potential blood-based biomarkers capable of providing prognostic and predictive information in cancer, they have not been incorporated into routine clinical practice. This resistance is due in part to technological limitations hampering CTC and cfDNA analysis, as well as a limited understanding of precisely how to interpret emergent biomarkers across various disease stages and tumor types. In recognition of these challenges, a group of researchers and clinicians focused on blood-based biomarker development met at the Canadian Cancer Trials Group (CCTG) Spring Meeting in Toronto, Canada on 29 April 2016 for a workshop discussing novel CTC/cfDNA technologies, interpretation of data obtained from CTCs versus cfDNA, challenges regarding disease evolution and heterogeneity, and logistical considerations for incorporation of CTCs/cfDNA into clinical trials, and ultimately into routine clinical use. The objectives of this workshop included discussion of the current barriers to clinical implementation and recent progress made in the field, as well as fueling meaningful collaborations and partnerships between researchers and clinicians. We anticipate that the considerations highlighted at this workshop will lead to advances in both basic and translational research and will ultimately impact patient management strategies and patient outcomes.     

Essentialism revisited: Evolutionary theory and the concept of mental disorder.

J. C. Wakefield's (1999) elaboration of his harmful dysfunction analysis (HDA) of mental disorder does little to address previous criticisms (S. O. Lilienfeld & L. Marino, 1995) and instead reveals further conceptual weaknesses in his position. The authors demonstrate that (a) a Roschian analysis can account for the results of all of Wakefield's conceptual experiments and predicts a number of judgments of disorder not predicted by the HDA, (b) the HDA is incapable in many cases of providing a scientifically nonarbitrary distinction between disorder and nondisorder, and (c) the HDA cannot account for failures of cultural exaptations, mismatches between evolutionary design and novel environments, or defenses against threat. The authors argue that the HDA has been convincingly falsified and discuss the failure of essentialistic concepts to resolve controversies in other domains of biological science. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of an Al2O3 dispersion on the adhesion of Al2O3 scales on aluminized Co-10% Cr alloys

The beneficial effect of dispersions of reactive-metal oxide particles on the adhesion of Cr₂O₃ and Al₂O₃ scales formed on heat-resisting alloys is wellknown. It has been shown that an Al₂O₃ dispersion in an alloy can improve the adhesion of a Cr₂O₃ scale, and it is of particular interest in assessing the various theoretical proposals for the effect to determine whether such a dispersion can affect the adhesion of an Al₂O₃ scale. In this investigation, a Co–10% Cr–1 % Al alloy was first internally oxidized to form an Al₂O₃ dispersion. This alloy was then aluminized so that on subsequent oxidation an Al₂O₃ scale developed. It was shown that the dispersion did indeed improve the scale adhesion. The implications of this result are discussed.     

Holographic reprocessing: Empirical evidence to reduce posttraumatic cognitions in women veterans with PTSD from sexual trauma and abuse.

Holographic reprocessing (HR) facilitates holistic reappraisal of attributions regarding interpersonal violence and maltreatment. The authors tested the feasibility to train therapists to run a protocol using HR to reduce negative thoughts associated with posttraumatic stress disorder (PTSD) in women veterans who have had sexual trauma or abuse. The study assessed pre- and postscores on the Posttraumatic Cognitions Inventory (PTCI) in a naturalistic clinical setting with 5 therapists. The protocol consisted of screening for PTSD, followed by an average of 9 HR treatment sessions. Twenty-two women were referred to the study; 17 enrolled and completed treatment (0% dropout rate). Significant decreases were found on all scales of the PTCI, with large effect sizes: total negative thoughts, t(16) = 4.42, p     

Sensory modality, temperament, and the development of sustained attention: A vigilance study in children and adults.

Applying optimal stimulation theory, the present study explored the development of sustained attention as a dynamic process. It examined the interaction of modality and temperament over time in children and adults. Second-grade children and college-aged adults performed auditory and visual vigilance tasks. Using the Carey temperament questionnaires (S. C. McDevitt & W. B. Carey, 1995), the authors classified participants according to temperament composites of reactivity and task orientation. In a preliminary study, tasks were equated across age and modality using d= matching procedures. In the main experiment, 48 children and 48 adults performed these calibrated tasks. The auditory task proved more difficult for both children and adults. Intermodal relations changed with age: Performance across modality was significantly correlated for children but not for adults. Although temperament did not significantly predict performance in adults, it did for children. The temperament effects observed in children-specifically in those with the composite of reactivity-occurred in connection with the auditory task and in a manner consistent with theoretical predictions derived from optimal stimulation theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)