Posttraumatic stress disorders in Vietnam veterans: Selected bibliographical addendum to Fairbank et al., Silver, and Arnold.

J. A. Fairbank et al (see record 1982-12226-001), presented a selected bibliography on contributions relevant to posttraumatic stress disorder (PTSD) in Vietnam veterans. Their selection included research and clinical reports found in psychological and medical journals, books and government publications, which were pertinent to epidemiology, etiology, symptomatology, and treatment of PTSD in Vietnam veterans, plus narratives by Vietnam veterans and research germane to PTSD from other conflicts. S. M. Silver (see record 1983-03626-001) updated Fairbank et al., with 171 since-published articles, reports, and other references. A. Arnold's (1987) bibliograpy contains over 1,000 clinical references, as well as accounts of the Vietnam War. This addendum is an attempt to update the enormous body of PTSD literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

High energy dry coating mixing: Elements on velocities,temperatures and melting

In dry coating processes no liquid, solvent, binder or water, is required. This makes them advantageous compared to wet coating alternative: being low cost, no drying step required, environmentally friendly (no volatile organic compounds related problems) and simple in operation. But there is still a lack of fundamental knowledge of the implied mechanisms. Often the process itself has been empirically designed and is not always well characterized.In this work, some hydrodynamic elements are developed in a high energy mixer used for dry coating: the specific behavior of the Nara hybridizer NHS-0 is investigated. In the first part, recirculation velocities and temperatures are derived during the process, or when the purge is on. The effects of the pressure purge and of the rotor velocity on the purge and the effect of the rotation on the temperature increase are studied. In the second part, a simple experimental approach is carried out to derive qualitatively the local temperature inside the apparatus with the help of polymers with different melting temperatures. This approach illustrates a first step for dry coating application with waxes.     

Segmentation of store choice models using stated preferences

The understanding and modelling of consumer shopping behaviour can increasingly only be fully realised by reference to market segments. Disaggregate choice modelling methods are able to take account of such behavioural heterogeneity, but are hampered by the poor quality of observed choice data on which they are calibrated. This paper shows how a segmented modelling strategy may be developed using stated preference data, and illustrates the methodology using the example of grocery shopping in Cardiff, South Glamorgan.     

Characterization of plutonium distribution in MIMAS MOX by image analysis

A better understanding of MOX fuel in-pile behaviour requires a very detailed characterization of the Pu distribution in the pellet before and after irradiation. Electron probe microanalysis (EPMA) can be used to determine the distributions of chemical elements with a spatial resolution of 1 μm. This paper describes the development of X-ray microanalysis techniques to produce semi-quantitative ‘maps’ of plutonium concentrations in order to rapidly characterize large areas of the fuel microstructure (1 mm²) with reasonable accuracy. A new segmentation technique based on statistical compatibility is then proposed, so as to finely describe the MIMAS MOX fuel microstructure. Two materials were finely characterized to demonstrate the reliability of this new method. In each case, the results demonstrate the good and reliable accuracy of this new characterization methodology. The analysis method used is currently able to identify three so-called phases (Pu-rich agglomerates, a coating phase and uranium-rich agglomerates), as well as to quantify the plutonium distribution and the plutonium content of these three phases. The impact of the fabrication process on the microstructure can be seen both in the surface distribution variations of the plutonium and in the local plutonium content variations.     

Variables in the Hiring Equation: Ensuring that the Right Candidate is Hired

When making the decision to hire one of several equally qualified candidates, IS managers fall back on their instincts and choose the candidate that “feels right.” They rely on personal chemistry, which is one of the variables in the hiring equation. Other equally important elements are: aptitude, attitude, and motivational factors.     

Using statistics to make expert systems “user-acquainted”

The user-acquainted feature collects user-specific data regarding the types of advice that have been sought over time and uses this historical information to update the probabilities to affect the firing of its rules and the ordering of the recommendations of the expert system. These updates are done on auser-specific basis so that the expert can more closely emulate a true expert by providing more informed advice. One example of a place where evidence suggests that such a feature would be useful is in the area of debugging of computer programs, especially in support of novice programmers who tend, as individuals, to commit similar classes of errors over time, but who, as a group, commit very different types of errors. We conjecture that the user-acquainted feature, which can keep track of the tendencies of the users and take them into account in the evaluation of diagnostics, will be more effectiveand efficient in determining the fault. In this paper, we discuss the statistical analyses necessary to implement this feature in an expert system for debugging errors in SAS.     

Local pH variation as an initial step in bacterial surface-sensing and biofilm formation

The development of surface-associated layers of matrix-embedded microbial populations, called biofilms, is a serious problem in many medical and industrial settings. These contaminations are difficult to eradicate because of the high resistance level acquired by the cells in their particular environment. From the very beginning of the colonization process, modifications of gene expression are observed and could, at least partially, explain biofilm resistance. In order to develop anti-biofilm molecules and surface treatments, it is of pivotal importance to identify the physico-chemical parameters which activate the sensor systems of pioneering microbes when they come into contact with a surface. The aim of our study was to examine the pH variations in the local micro-environment created between the cell layer and the surface after bacteria adhesion. Using an ion-sensitive field effect transistor (ISFET), as a substratum, colonized by a curli hyperproducing strain known to form biofilms, we observed that the evolution of the pH change was significantly different in the micro-compartment in contact with the electrochemical sensor compared to that within the liquid phase.     

pH‐Cleavable Nucleoside Lipids: A New Paradigm for Controlling the Stability of Lipid‐Based Delivery Systems

Lipid‐based delivery systems are an established technology with considerable clinical acceptance and several applications in human. Herein, we report the design, synthesis and evaluation of novel orthoester nucleoside lipids (ONLs) for the modulation of liposome stability. The ONLs contain head groups with 3′‐orthoester nucleoside derivatives featuring positive or negative charges. The insertion of the orthoester function in the NL structures allows the formation of pH‐sensitive liposomes. ONL‐based liposomes can be hydrolyzed to provide nontoxic products, including nucleoside derivatives and hexadecanol. To allow the release to be tunable at different hydrolysis rates, the charge of the polar head structure is modulated, and the head group can be released at a biologically relevant pH. Crucially, when ONLs are mixed with natural phosphocholine lipids (PC), the resultant liposome evolves toward the formation of a hexadecanol/PC lamellar system. Biological evaluation shows that stable nucleic acid lipid particles (SNALPs) formulated with ONLs and siRNAs can effectively enter into tumor cells and release their nucleic acid payload in response to an intracellular acidic environment. This results in a much higher antitumor activity than conventional SNALPs. The ability to use pH‐cleavable nucleolipids to control the stability of lipid‐based delivery systems represents a promising approach for the intracellular delivery of drug cargos.     

Numerical investigation of DQMoM-IEM as a turbulent reaction closure

This paper investigates a mean reaction rate closure for turbulent reacting flows called the Direct Quadrature Method of Moments using the Interaction by Exchange with the Mean micromixing model (DQMoM-IEM). The method was first introduced for reacting flows by Fox (Computational Models for Turbulent Reacting Flows, Cambridge University Press, 2003). We present a systematic study that considers several important new aspects of the method. In particular we introduce a new analytic expression for the DQMoM-IEM source terms. We present a rigourous numerical investigation and discuss problems of boundedness and singularity in detail. We introduce a filter function to overcome these issues in the general case and present analytic integrals for special cases of specific terms. We extend the methodology to take advantage of these developments and show details of the implementation in a commercial computational fluid dynamics (CFD) code. We present an extensive set of numerical experiments and validation. The method is proven for a problem known from the literature which includes an isothermal dimerisation process. Experimental and transported probability density function (PDF) data compare reasonably well. The method is discussed critically and areas for further research are suggested to make the method more practical.     

Laboratory studies into how glass-reinforced plastic (GRP) vat surfaces can be repaired without causing migration of styrene into foodstuffs

Glass–fiber-reinforced plastic (GRP) vats are used widely for the storage of foodstuffs and potable water. As the inner surfaces deteriorate during decades of use, they need to be repaired. The unsaturated polyester resins that are used for recoating are crosslinked with styrene which can cause taint and odor problems. This article describes some coating parameters that affect the content of residual styrene and its subsequent migration. The influences of cure temperature and duration, along with the effect of washing with warm detergent solution, were investigated. Cured specimens were tested for their residual styrene content and for styrene migration into the food simulants, distilled water, 3% acetic acid, and 15% ethanol. The dominant factor in reducing the amount of residual styrene is the temperature. The resin self-heats as it cures, typically up to 50°C. Thus, any further lowering of the styrene content requires a higher cure temperature than this. A 3-h cure at 80°C reduced both the residual content and the migration levels by about 100-fold. At lower cure temperatures, the heating effect of washing at 60°C is more important than the washing effect of the detergent. When less catalyst was used the residual styrene levels rose dramatically, from 70 to 360 to 1300 mg/kg for the normal dose, half and quarter the normal dose, respectively. There was a linear relationship between residual content in the GRP and the migration levels. This correlation could be used for monitoring the quality of vats repaired in situ, using styrene-based coating resins.