The influence of creative process engagement on employee creative performance and overall job performance: A curvilinear assessment.

Integrating theories addressing attention and activation with creativity literature, we found an inverted U-shaped relationship between creative process engagement and overall job performance among professionals in complex jobs in an information technology firm. Work experience moderated the curvilinear relationship, with low-experience employees generally exhibiting higher levels of overall job performance at low to moderate levels of creative process engagement and high-experience employees demonstrating higher overall performance at moderate to high levels of creative process engagement. Creative performance partially mediated the relationship between creative process engagement and job performance. These relationships were tested within a moderated mediation framework. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rapid continuous 3D printing of customizable peripheral nerve guidance conduits

Engineered nerve guidance conduits (NGCs) have been demonstrated for repairing peripheral nerve injuries. However, there remains a need for an advanced biofabrication system to build NGCs with complex architectures, tunable material properties, and customizable geometrical control. Here, a rapid continuous 3D-printing platform was developed to print customizable NGCs with unprecedented resolution, speed, flexibility, and scalability. A variety of NGC designs varying in complexity and size were created including a life-size biomimetic branched human facial NGC. In vivo implantation of NGCs with microchannels into complete sciatic nerve transections of mouse models demonstrated the effective directional guidance of regenerating sciatic nerves via branching into the microchannels and extending toward the distal end of the injury site. Histological staining and immunostaining further confirmed the progressive directional nerve regeneration and branching behavior across the entire NGC length. Observational and functional tests, including the von Frey threshold test and thermal test, showed promising recovery of motor function and sensation in the ipsilateral limbs grafted with the 3D-printed NGCs.     

Branched‐Tail Lipid Nanoparticles Potently Deliver mRNA In Vivo due to Enhanced Ionization at Endosomal pH

The potential of mRNA therapeutics will be realized only once safe and effective delivery systems are established. Unfortunately, delivery vehicle development is stymied by an inadequate understanding of how the molecular properties of a vehicle confer efficacy. Here, a small library of lipidoid materials is used to elucidate structure–function relationships and identify a previously unappreciated parameter—lipid nanoparticle surface ionization—that correlates with mRNA delivery efficacy. The two most potent materials of the library, 306O₁₀ and 306O_i10, induce substantial luciferase expression in mice following a single 0.75 mg kg^?1 mRNA dose. These lipidoids, which have ten‐carbon tails and identical molecular weights, vary only in that the 306O₁₀ tail is straight and the 306O_i10 tail has a one‐carbon branch. Remarkably, this small difference in structure conferred a tenfold improvement in 306O_i10 efficacy. The enhanced potency of this branched‐tail lipidoid is attributed to its strong surface ionization at the late endosomal pH of 5.0. A secondary lipidoid library confirms that O_i10 materials ionize more strongly and deliver mRNA more potently than lipidoids containing linear tails. Together, these data highlight the exquisite control that lipid chemistry exerts on the mRNA delivery process and show that branched‐tail lipids facilitate protein expression in animals.     

Production,consumption, and protection: perspectives from North America on the multifunctional transition in rural planning

ABSTRACT

Rural areas encompass landscapes that range from peri-urban to very isolated ‘deep rural’ areas; from rapidly growing high amenity retirement and second home communities to dilapidated near-ghost towns; from those with strong economies in agriculture, natural resource extraction, tourism, and high tech to those with shrinking economies. In addition, such global issues as climate change, food security, and future energy supply have enormous implications for rural places. In these circumstances planning thought and action are confronted – often simultaneously – with physical development – planning for growth and change; production – of traditional agricultural and natural resource outputs but also new outputs such as renewable energy and ecosystem services; and protection – of the natural environment, cultural resources, and social systems. This article draws from the literature and interviews of rural specialists to explore the current tensions between production, consumption, and protection and emerging responses to them, through an exploration of North American rural planning.     

Effects of anthropogenic inputs on the organic quality of urbanized streams

Due to arid conditions, population growth, and anthropogenic impacts from agricultural and urban development, wastewater effluent makes up an increasingly large percentage of surface water supplies promoting concerns about the potential ecological and human health effects associated with the organic quality of surface waters receiving treated wastewater discharge. Anthropogenic inputs alter the quality and quantity of organic carbon and also affect the ability of aquatic ecosystems to retain or transform carbon and other nutrients. In this paper, we use pyrolysis-GC/MS (Py-GC/MS) as a tool to examine whether the dissolved organic carbon (DOC) in suburban streams influenced by anthropogenic inputs displays an organic signature that is structurally different from natural organic material (NOM). Py-GC/MS was not only able to differentiate among stream sites that received discharge from upstream wastewater treatment plants and those that did not, but also distinguished stream sites influenced significantly by storm water. Distinct organic signatures were evident in stream waters with upstream wastewater treatment plant discharges regardless of the distance from effluent discharge, indicative of the persistent nature of effluent-derived organic material (EfOM). The pyrolysis fragments of 3-methyl-pyridine, 2-methyl-pyridine, pyrrole, and acetamide were identified as indicators of EfOM, supporting previous research that has suggested that protein and aminosugar derivitives are possible wastewater markers. Furthermore, pyrolysis fragments associated with soil polycarboxylic acids correlated highly with stream sites having the least anthropogenic influences.     

Uptake of divalent ions (Mn+2 and Ca+2) by heat-set whey protein gels

Divalent salts are used commonly for gelation of polymer molecules. Calcium, Ca(+2), is one of the most common divalent ions that is used in whey protein gels. Manganese, Mn(+2), is also divalent, but paramagnetic, enhancing relaxation decay rates in magnetic resonance imaging (MRI) and can be used as a probe to understand the behavior of Ca(+2) in whey protein gels. The objective of this study was to investigate the diffusion of Ca(+2) and Mn(+2) ions in heat-set whey protein gels by using MRI and nuclear magnetic resonance (NMR) relaxometry. Whey protein gels were immersed in solutions containing MnCl(2) and CaCl(2) at neutral pH. Images obtained with gels immersed in MnCl(2) solution revealed a relaxation sink region in the gel's surface and the thickness of the region increased with time. These "no signal" regions in the MR images were attributed to uptake of Mn(+2) by the gel. Results obtained with CaCl(2) solution indicated that since Ca(+2) did not have the paramagnetic effect, the regions where Ca(+2) diffused into the gel exhibited a slight decrease in signal intensity. The relaxation spectrums exhibited 3 populations of protons, for gels immersed in MnCl(2) solution, and 2 populations for gels in CaCl(2) solution. No significant change in T(2) distributions was observed for the gels immersed in CaCl(2) solution. The results demonstrated that MRI and NMR relaxometry can be used to understand the diffusion of ions into the whey protein gel, which is useful for designing gels of different physical properties for controlled release applications. PRACTICAL APPLICATION: Design of food systems for delivery of bioactive compounds requires knowledge of diffusion rates and structure. Utilizing magnetic resonance imaging the diffusion rates of ions can be measured. Relaxation spectra could yield information concerning molecular interactions.     

The fractionation and purification of gliadins by hydrophobic interaction chromatography

The apolar nature of wheat gliadins has been studied. Apolar properties have been exploited to fractionate components by hydrophobic interaction chromatography and fractions have been analysed further by polyacrylamide gel electrophoresis. Experiments were carried out in pH 5.0 buffer in absence of additives such as urea or dimethylformamide. Gliadin was not retarded by ethyl or butyl agarose but showed a strong affinity for both the phenyl and octyl derivatives. The strength of the hydrophobic interactions was such that aqueous alcohol was required to achieve appreciable desorption. Even so, only two-thirds of the bound gliadin could be eluted with aqueous ethanol alone; complete desorption required the presence of small concentrations of tetramethylammonium chloride. The elution of protein from columns followed the general order ω-,β-, α-, and γ-gliadin, respectively. This procedure provides a simple system for the fractionation of wheat prolamines under mild conditions. Results suggest that a higher degree of resolution may be attainable by further modification of experimental conditions. Interaction of gliadin with nonpolar groups covalently bound to agarose apparently reflects the presence of hydrophobic patches on the surface of the gliadin molecule.     

Initial adhesion of Listeria monocytogenes to solid surfaces under liquid flow

Some strains of the food borne pathogen Listeria monocytogenes persist in food processing environments. The exact reason behind this phenomenon is not known, but strain differences in the ability to adhere to solid surfaces could offer an explanation. In the present work, initial adhesion of nine strains of L. monocytogenes was investigated under liquid flow at two levels of shear stress on six different surfaces using a flow chamber set-up with microscopy measurements. The surfaces tested were glass and PVC, and glass coated with beef extract, casein, and homogenised and unhomogenised milk. In addition, the effect of prior environmental stress (5% NaCl, low nutrient availability) on initial adhesion was investigated. The hydrophobicity of the investigated surfaces was determined by contact angle measurements and the surface properties of the investigated L. monocytogenes strains were determined using Microbial Adhesion To Solvents (MATS). All surfaces with the exception of PVC were found to be hydrophilic. Strain differences were found to significantly influence the initial adhesion rate (IAR) of all nine strains to all the surfaces (p < 0.05) at both low and high shear stress. Furthermore, there was a significant effect of the surfaces tested (p < 0.05) in the adhesion ability of almost all strains. The IAR was affected by flow rate (shear stress) as seen by a decrease in adhesion at high shear stress for most strains. A significant effect of interactions between strain-surface and strain-shear stress (p < 0.001) was observed but not of interactions between surface-shear stress. No correlation between surface hydrophobicity and IAR was observed. Addition of 5% NaCl during propagation resulted in a decrease in IAR whilst propagation in low nutrient media caused an increase indicating a general change in surface characteristics under these conditions. Known persisting strains did not display general better adherence.