Increasing the water uptake of wood veneers through plasma treatment at atmospheric pressure

In order to provide a database which documents the influence of plasma treatment on water uptake of wood veneers, veneers of 27 wood species underwent immersion tests in untreated and plasma-treated states. Plasma treatment was executed using an air driven dielectric barrier discharge at atmospheric pressure. The results showed that plasma treatment led to significantly improved water uptake for most of the wood species, but some wood species remained unaffected after plasma treatment.     

Thermal actuators featuring large displacements for passive temperature sensing

The thermal actuator presented in this paper consists of two symmetrically V-shaped beam stacks, where each stack consists of six beams in parallel. The stacks are coupled facing each other and slightly shifted along the mirror axis. Both stacks are connected to a lever beam and fixed at four anchor regions to the substrate. Due to the difference in the coefficient of thermal expansion of the material of the beams and the one of the substrate, the tip of the lever moves perpendicular to the mirror axis. The device is fabricated from galvanic deposited nickel on a silicon substrate. Finite element simulations were carried out to optimize the design with respect to the sensitivity and the maximum mechanical stress. The stress needs to be lower than the yield strength of the material. Otherwise, plastic deformations of the beams would lead to irreversible deflections of the beam tip. This limits the overall sensitivity of the design. First results of the device with 400 μm long bent beams show a linear behavior and a sensitivity of 0.5 μm/K and forces of 66 μN/K for a temperature range of ?30 °C up to +40 °C.     

From dynamic capabilities to ERP enabled business improvements: The mediating effect of the implementation project

This study explores whether an Enterprise Resource Planning (ERP) implementation project mediates the relationship between dynamic pre-adoption capabilities and ERP-enabled business improvements. The results from our field survey of large ERP adopters in Austria suggest that the effects of the two out of three selected dynamic capabilities are dependent on the properties of the underlying organizational transformation project. While external information acquisition and IT governance capabilities are fully mediated by the performance of the ERP implementation project, decision making only directly impacts business capabilities. These results further our understanding about the role of the implementation project for ERP value creation and the different natures of capability relationships. We call for more research on co-presence conditions related to dynamic capabilities and IT transformation project performance.     

Evaluation of polycaprolactone − poly‐D,L‐lactide copolymer as biomaterial for breast tissue engineering

The potential of the copolymer polycaprolactone‐co‐ poly‐d ,l ‐lactic acid (PCLLA ) as a biomaterial for scaffold‐based therapy for breast tissue engineering applications was assessed. First, the synthesized PCLLA was evaluated for its processability by means of additive manufacturing (AM ). We found that the synthesized PCLLA could be fabricated into scaffolds with an overall gross morphology and porosity similar to that of polycaprolactone. The PCLLA scaffolds possessed a compressive Young's modulus (ca 46 kPa ) similar to that of native breast (0.5 ? 25 kPa ), but lacked thermal stability and underwent thermal degradation during the fabrication process. The PCLLA scaffolds underwent rapid degradation in vitro which was characterized by loss of the scaffolds' mechanical integrity and a drastic decrease in mass‐average molar mass (M _w) and number‐average molar mass (M _n) after 4 weeks of immersion in phosphate buffer solution maintained at 37 °C. The tin‐catalysed PCLLA scaffold was also found to have cytotoxic effects on cells. Although the initial mechanical properties of the PCLLA scaffolds generally showed potential for applications in breast tissue regeneration, the thermal stability of the copolymer for AM processes, biocompatibility towards cells and degradation rate is not satisfactory at this stage. Therefore, we conclude that research efforts should be geared towards fine‐tuning the copolymer synthesizing methods. © 2016 Society of Chemical Industry     

Sweet taste receptor expression in ruminant intestine and its activation by artificial sweeteners to regulate glucose absorption

Absorption of glucose from the lumen of the intestine into enterocytes is accomplished by sodium-glucose co-transporter 1 (SGLT1). In the majority of mammalian species, expression (this includes activity) of SGLT1 is upregulated in response to increased dietary monosaccharides. This regulatory pathway is initiated by sensing of luminal sugar by the gut-expressed sweet taste receptor. The objectives of our studies were to determine (1) if the ruminant intestine expresses the sweet taste receptor, which consists of two subunits [taste 1 receptor 2 (T1R2) and 3 (T1R3)], and other key signaling molecules required for SGLT1 upregulation in nonruminant intestines, and (2) whether T1R2-T1R3 sensing of artificial sweeteners induces release of glucagon-like peptide-2 (GLP-2) and enhances SGLT1 expression. We found that the small intestine of sheep and cattle express T1R2, T1R3, G-protein gustducin, and GLP-2 in enteroendocrine L-cells. Maintaining 110-d-old ruminating calves for 60 d on a diet containing a starter concentrate and the artificial sweetener Sucram (consisting of saccharin and neohesperidin dihydrochalcone; Pancosma SA, Geneva, Switzerland) enhances (1) Na⁺-dependent d-glucose uptake by over 3-fold, (2) villus height and crypt depth by 1.4- and 1.2-fold, and (3) maltase- and alkaline phosphatase-specific activity by 1.5-fold compared to calves maintained on the same diet without Sucram. No statistically significant differences were observed for rates of intestinal glucose uptake, villus height, crypt depth, or enzyme activities between 50-d-old milk-fed calves and calves maintained on the same diet containing Sucram. When adult cows were kept on a diet containing 80:20 ryegrass hay-to-concentrate supplemented with Sucram, more than a 7-fold increase in SGLT1 protein abundance was noted. Collectively, the data indicate that inclusion of this artificial sweetener enhances SGLT1 expression and mucosal growth in ruminant animals. Exposure of ruminant sheep intestinal segments to saccharin or neohesperidin dihydrochalcone evokes secretion of GLP-2, the gut hormone known to enhance intestinal glucose absorption and mucosal growth. Artificial sweeteners, such as Sucram, at small concentrations are potent activators of T1R2-T1R3 (600-fold > glucose). This, combined with oral bioavailability of T1R2-T1R3 and the understanding that artificial sweetener-induced receptor activation evokes GLP-2 release (thus leading to increased SGLT1 expression and mucosal growth), make this receptor a suitable target for dietary manipulation.     

Microstructure–strength models for heat treatment of Al–Si–Mg casting alloys I: microstructure evolution and precipitation kinetics

A comprehensive microstructure–strength mathematical model for the heat treatment of Al–Si–Mg casting alloys is presented. As part of the model development, the evolution of microstructure and mechanical properties during heat treatment of an industrially cast A356 aluminium alloy was studied in an extensive experimental investigation. For the solution treatment process, the changes in dendritic composition and eutectic morphology in the temperature range 773–833 K (500–560°C) were quantified using microprobe and image analysis techniques. For natural and artificial ageing, the kinetics of precipitation/clustering was determined using an isothermal calorimetry technique in conjunction with hardness and mechanical property measurements. Two other Al–Si–Mg model alloy compositions were used to study the effects of alloy chemistry on microstructure response during heat treatment. The overall aim of the experimental work presented here is to facilitate the development of a comprehensive microstructure–strength model for the heat treatment of Al–Si–Mg casting alloys that will be presented in part II of this paper.

On présente un modèle mathématique détaillé de la microstructure-résistance du traitement thermique des alliages de moulage d'Al–Si–Mg. Faisant partie du développement du modèle, on a étudié l'évolution de la microstructure et des propriétés mécaniques lors du traitement thermique d'un alliage d'aluminium A356 moulé industriellement lors d'un examen expérimental de grande envergure. Pour le traitement de mise en solution, on a quantifié les changements de la composition dendritique et la morphologie de l'eutectique dans la gamme de température de 773 à 833 K (500 à 560 °C) en utilisant les techniques de la microsonde et de l'analyse d'image. Pour le vieillissement naturel et artificiel, on a déterminé la cinétique de précipitation/agrégation en utilisant une technique de calorimétrie isotherme en conjonction avec les mesures de dureté et de propriétés mécaniques. On a utilisé deux autres compositions de l'alliage modèle d'Al–Si–Mg pour étudier les effets de la chimie de l'alliage sur la réponse de la microstructure lors du traitement thermique. Le but global du travail expérimental présenté ici est de faciliter le développement d'un modèle détaillé de microstructure-résistance du traitement thermique des alliages de moulage d'Al–Si–Mg qui sera présenté dans la seconde partie de cet article.     

On the failure of scientific research: an analysis of SBIR projects funded by the U.S. National Institutes of Health

Scientometrics - The Small Business Innovation Research (SBIR) program is the primary source of public funding in the United States for research by small firms on new technologies, and the National...     

Robust Empirical Predictions of Residual Performance of Damaged Composites with Quantified Uncertainties

Robust predictions with estimated uncertainties were made for the residual strength of impact-damaged composite laminates based on simple non-destructive measurements of the size of the damage from ultrasound C-scans. Experimental data was acquired for two sets of composite coupons, one with a crossply and the other with a quasi-isotropic layup. The laminates were subject to drop-weight impacts, non-destructively evaluated using ultrasound and then loaded to failure in bending. An empirical model of the residual strength of each laminate layup, as a function of the ultrasound measurements, was generated by fitting a Bayesian linear regression model to the normalised measured data. Bayesian linear regression was demonstrated to provide conservative estimates when only minimal data is available. Unlike classical regression, this technique provides a robust treatment of outliers, which avoids underestimation of residual strength. The Leave-One-Out-Cross-Validation (LOOCV) metric was used to assess the performance of models allowing for the quantitative comparison of the predictive power of regression models as well as being consistent in the presence of outliers in the data. The LOOCV metric indicated that predictions of residual strength are up to 25% more accurate when based on damage area than when using measurements of the damage width or length. The proposed approach provides a robust methodology for performing damage assessments in safety critical composite components based on reliable predictions with quantified uncertainties.     

The multiphysics modeling of heat and moisture induced stress and strain of historic building materials and artefacts

The basic structure of historic sites and their associated interior artefacts can be damaged or even destroyed by climate change. The evaluation of combined heat and moisture induced stress and strain (HMSS) can predict possible damage-related processes. In this paper, the development of one- and two-dimensional HMSS models of building materials and artefacts in COMSOL Multiphysics Version 4, a commercial finite element software, is presented. The validation of the numerical models is revealed using analytical, numerical and experimental solutions. As a result, the HMSS model was shown to be an adequate predictive tool to determine possible damage-related processes in building assemblies and artefacts.