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• The optimal treatment modality for CSP is unknown. • CT-guided needle aspiration and methotrexate injection may be used for management of CSP. • Three cases of CSPs successfully treated with CT-guided methotrexate injection. [ABSTRACT FROM AUTHOR]

The prediction of collapse of structures has gained growing attention recently, as it is important to be able to predict and model structural collapse due to extreme loads. A lack of accurate, pragmatic, and validated structural collapse models currently limits the capabilities for predicting collapse due to possible extreme loads. This research compares three finite element deletion strategies that account implicitly for fracture under monotonic loading to be used as predictive tools for collapse modeling of steel structures. The first strategy employs a Void Growth Model (VGM) to simulate the initiation of softening and the Hillerborg model for modeling of material softening, followed by an element deletion strategy that is developed in this framework. The second strategy adds a Bao-Wierzbicki model to the VGM strategy (VGM-BW) in order to account more directly for fracture initiation in lower and negative triaxiality regions. The third strategy is a constant critical strain (CS) approach that does not include softening but instead deletes an element when it achieves a peak equivalent plastic strain. The parameters of the VGM strategy were calibrated to a comprehensive set of experimental test results of circumferentially notched tensile (CNT) coupon specimens, the Bao-Wierzbicki parameters in VGM-BW strategy were determined analytically through tensile coupon (TC) specimens, and the CS approach used a constant value for equivalent plastic strain at softening initiation. These strategies were then validated through comparison with experimental test results of specimens commonly used for material characterization of steel. The results establish the accuracy and effectiveness of the VGM strategy for high-fidelity parametric simulation capabilities for collapse of steel structures and provide recommendations for where additional experimental research is needed to validate regions of low and negative triaxiality. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to enhance the CAPS tool by clarifying the concept of coping, using item response theory (IRT) to shorten and assess the metric equivalence of the scale, and testing the preliminary validity of the resulting shortened scale. Methods: A descriptive design of participants from different ethnic backgrounds was employed (USA n = 347 and Panama n = 327). To select items for the shortened CAPS, a well-established multi-step process grounded in IRT was used. Further, a coping ladder was created to approximate the a priori perceived location/difficulty of each item along the coping trait scale. Items for the shortened scale were selected based on considerations central to the middle range theory of coping and adaptation processing and the results of the item calibration and model testing. Results: A total of 15 items were selected. The selected items were well distributed on the coping ladder and all basic subconcepts of the middle range theory were included. Further the sum of the DIF size for the selected short form items is -0.01, so the overall bias of the total score is minimal. Finally, concurrent and divergent validity of the new scale was demonstrated in two separate correlational studies. Conclusion: The 15-item Coping and Adaptation Processing Scale (CAPS)-Short-Form can be a practical tool to effectively and efficiently measure coping and adaptation in both practice and research for people dealing with both chronic and acute health conditions. [ABSTRACT FROM AUTHOR]

Objectives: To review the evidence supporting the validity of health literacy (HL) measures for ethnic minority populations.Methods: PubMed, CINAHL, and PsycINFO databases were searched for HL measures between 1965 and 2013.Results: A total of 109HL measures were identified; 37 were non-English HL measures and 72 were English language measures. Of the 72 English language measures, 17 did not specify the racial/ethnic characteristic of their sample. Of the remaining 55 measures, 10 (18%) did not include blacks, 30 (55%) did not include Hispanics, and 35 (64%) did not include Asians in their validation sample. When Hispanic and Asian Americans were included, they accounted for small percentages in the overall sample. Between 2005-2013, a growing number of REALM and TOFHLA translations were identified, and new HL measures for specific cultural/linguistic groups within and outside the United States were developed.Conclusions: While there are a growing number of new and translated HL measures for minority populations, many existing HL measures have not been properly validated for minority groups.Practice Implications: HL measures that have not been properly validated for a given population should be piloted before wider use. In addition, improving HL instrument development/validation methods are imperative to increase the validity of these measures for minority populations. [ABSTRACT FROM AUTHOR]

Neuronal communication relies on the fusion of neurotransmitter-containing vesicles with the plasma membrane. The soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) proteins initiate membrane fusion through the formation of the SNARE complex, a process tightly regulated by Secl/Muncl8-1 (SM) proteins. The emerging trend is that SM proteins promote SNARE-mediated membrane fusion by binding to a Syntaxin N-terminal motif. Here we report that mutations in the hydrophobic pocket of Muncl8-1 (F115E and E132A), predicted to disrupt the N-terminal Sxla interaction have a modest effect on binding to Sxla in its free state, but abolish binding to the SNARE complex. Overexpression of the Muncl8-1 mutant in PC12 cells lacking Muncl8-1 rescues both neuroexocytosis and the plasma membrane localization of Syntaxin. However, total internal reflection fluorescence microscopy analysis reveals that expression of a Muncl8-1 double mutant reduces the rate of vesicle fusion, an effect only detectable at the onset of stimulation. The Muncl8-1 hydrophobic pocket is therefore critical for SNARE complex binding. However, mutations abrogating this interaction have a limited impact on Ca2+-dependent exocytosis in PC12 cells. [ABSTRACT FROM AUTHOR]

• Two FE deletion strategies that account for fracture are compared and validated. • Specific parameters' influence on performance of FE deletion strategies is discussed. • FE deletion strategies that account for triaxiality have greatest degree of accuracy. Collapse prediction of steel structures should incorporate a finite element model that accounts for ductile fracture through material separation in critical structural members. Finite element deletion approaches have been used successfully in the past to account for fracture in steel members. However, the current common approach in collapse modeling of steel structures, a constant critical strain strategy (CS), typically requires recalibration when used with different structural configurations due to the fact that it does not account for triaxiality, which is a primary parameter in ductile fracture. To better predict structural response of steel structures undergoing collapse, it is important to study the effect of triaxiality on fracture in steel structures. A new finite element deletion approach that accounts for triaxiality was previously proposed, calibrated, and validated in small steel specimens for use in predicting collapse of steel structures. In this approach, fracture initiation is modeled using Void Growth Model (VGM) and the subsequent softening of the material to element deletion is modeled by a Hillerborg model. This paper describes the change of triaxiality, equivalent plastic strain, and other parameters during the duration of the loading, influencing the strategies implemented and provides explanation for the performance shown. In addition, the paper examines the effect of triaxiality on accurately predicting fracture in steel structures through comparison of VGM to CS strategy with validation in simulations of full-scale structural steel connection and frame tests without recalibration. The VGM strategy provided an accurate prediction based on calibration to test results that are most widely available for different types of structural steels, while CS strategy frequently provided less accurate results. The VGM strategy thus allows for an accurate collapse modeling of steel structures for use by researchers, code developers, and practitioners who address collapse of steel structures. [ABSTRACT FROM AUTHOR]

In this paper we propose a novel chemical process for the generation of water-soluble polysaccharides from soy spent flake, a by-product of the soy food industry. This process entails treatment of spent flake with hydrogen peroxide at an elevated temperature, resulting in the release of more than 70% of the original insoluble material as high molar mass soluble polysaccharides. A design of experiment was used to quantify the effects of pH, reaction time, and hydrogen peroxide concentration on the reaction yield, average molar mass, and free monosaccharides generated. The resulting product is low in protein, fat, and minerals and contains predominantly water-soluble polysaccharides of high molar mass, including arabinan, type I arabinogalactan, homogalacturonan, xyloglucan, rhamnogalacturonan, and (glucurono)arabinoxylan. This treatment provides a straightforward approach for generation of soluble soy polysaccharides and opens a new range of opportunities for this abundant and underutilized material in future research and industrial applications. [ABSTRACT FROM AUTHOR]

The botulinum neurotoxins (BoNTs) are di-chain bacterial proteins responsible for the paralytic disease botulism. Following binding to the plasma membrane of cholinergic motor nerve terminals, BoNTs are internalized into an endocytic compartment. Although several endocytic pathways have been characterized in neurons, the molecular mechanism underpinning the uptake of BoNTs at the presynaptic nerve terminal is still unclear. Here, a recombinant BoNT/A heavy chain binding domain (Hc) was used to unravel the internalization pathway by fluorescence and electron microscopy. BoNT/A-Hc initially enters cultured hippocampal neurons in an activity-dependent manner into synaptic vesicles and clathrin-coated vesicles before also entering endosomal structures and multivesicular bodies. We found that inhibiting dynamin with the novel potent Dynasore analog, Dyngo-4a™, was sufficient to abolish BoNT/A-Hc internalization and BoNT/A-induced SNAP25 cleavage in hippocampal neurons. Dyngo-4a also interfered with BoNT/A-Hc internalization into motor nerve terminals. Furthermore, Dyngo-4a afforded protection against BoNT/A-induced paralysis at the rat hemidiaphragm. A significant delay of >30% in the onset of botulism was observed in mice injected with Dyngo-4a. Dynamin inhibition therefore provides a therapeutic avenue for the treatment of botulism and other diseases caused by pathogens sharing dynamin-dependent uptake mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: The Cre/loxP-system has become an invaluable tool for the generation of tissue-specific gene disruption in mice. However, because Cre recombinase excision of individual genes can be variable, an accurate and sensitive method is necessary to determine the ultimate level of gene disruption. The analysis of gene disruption is particularly difficult for tissue that has been fixed for (immuno)histochemical analysis with paraformaldehyde. Here, we describe a simple, rapid and cost effective method for measurement of gene disruption using quantitative real-time PCR, through application to the analysis of PEX13 gene disruption in a brain-specific PEX13 mouse mutant. We show that this general protocol is suitable for both normal and paraformaldehyde-fixed tissue. [Copyright &y& Elsevier]

The viscosity of an optical fibre over 1000–1150°C is studied by inscribing an optical fibre Bragg grating that can withstand temperatures up to 1200°C and monitoring fibre elongation under load through the Bragg wavelength shift. This optical interrogation offers high accuracy and reliability compared with direct measurements of elongation, particularly at lower temperatures, thus avoiding significant experimental error. An excellent Arrhenius fit is obtained from which an activation energy for viscous flow of E a =450kJmol−1 is extracted; addition of an additional temperature-dependent pre-exponential does not change this value. The log plot of viscosity is found overall to be consistent with that reported in the literature for silica measurements on rods and beams, but substantially higher than past work reported for optical fibres. The annealing and strain temperatures for an optical fibre were derived as 1114°C and 1010°C. However, it is shown that, because regenerated gratings already involve a post-annealing process at higher temperature, the structures are equilibrated and much more relaxed compared with normal fibres, making viscosity measurements meaningful. This work highlights the need to stabilize components for operation in harsh environments before their application, despite some mechanical compromise. Given the increasing expectation of all-optical waveguide technologies operating >1000°C, the need to study the behaviour of glass over the long term brings added significance to the basic understanding of glass in this regime. [ABSTRACT FROM AUTHOR]