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Background: Neuronal lamination is a hallmark of the mammalian central nervous system (CNS) and underlies connectivity and function. Initial formation of this tissue architecture involves the integration of various signaling pathways that regulate the differentiation and migration of neural progenitor cells. Results: Here, we demonstrate that mTORC1 mediates critical roles during neuronal lamination using the mouse retina as a model system. Down‐regulation of mTORC1‐signaling in retinal progenitor cells by conditional deletion of Rptor led to decreases in proliferation and increased apoptosis during embryogenesis. These developmental deficits preceded aberrant lamination in adult animals which was best exemplified by the fusion of the outer and inner nuclear layer and the absence of an outer plexiform layer. Moreover, ganglion cell axons originating from each Rptor‐ablated retina appeared to segregate to an equal degree at the optic chiasm with both contralateral and ipsilateral projections displaying overlapping termination topographies within several retinorecipient nuclei. In combination, these visual pathway defects led to visually mediated behavioral deficits. Conclusions: This study establishes a critical role for mTORC1‐signaling during retinal lamination and demonstrates that this pathway regulates diverse developmental mechanisms involved in driving the stratified arrangement of neurons during CNS development. Key Findings: Reduced mTORC1‐signaling in retinal progenitor cells leads to decreases in proliferation and increases in apoptosis.Proliferation and apoptotic deviations precede aberrant retinal lamination best exemplified by a fusion of the outer and inner nuclear layers and the absence of an outer plexiform layer.Aberrant retinal lamination is correlated with irregular dLGN termination topographies.Irregular dLGN termination topographies are associated with visual behavioural changes. [ABSTRACT FROM AUTHOR]

The effect of voids on the moisture uptake and transverse modulus and strength of a unidirectional glass/epoxy composite has been examined. To create voids, a foaming agent was mixed with the liquid epoxy resin prior to infusion. Micrographs of polished cross-sections indicate that voids are close to spherical in shape appearing in the matrix and at the fiber/matrix interface. The fiber, matrix, and void contents were analyzed by micrograph, burn-off, and density (Archimedes) methods. The void contents in the void-free and void-containing composites were respectively close to zero and 21%. Specimens were immersed in distilled water at 40°C until saturation. The weight gain was monitored periodically. For the void-free specimens, saturation moisture contents of about 0.60%. The void-containing specimens absorbed much more water, about 5%. The Fickian diffusion model provided good fits to experimental data although the transport mechanism for the void-containing composite appeared non-Fickian. Young's modulus of the void-free composite was slightly affected by water absorption, although, the transverse tensile strength dropped significantly. Voids were found to substantially reduce transverse modulus and strength about 70%, for both dry and water saturated specimens. Moisture content analysis was in good agreement with experiments for the void-free composite but over-predicted the moisture content for the voidcontaining composite. Micromechanics predictions of the transverse modulus were within 21% of the experimental results for void-free and void containing composites at dry and water saturated conditions. [ABSTRACT FROM AUTHOR]

Coronal section of a mouse embryonic head at E16.5 showing green Isl1/2 positive ganglion and amacrine cells within the neural retina in addition to red Caspase‐3 positive cells within the developing eye lid junction. Leif Carlsson, Christoffer Nord, Iwan Jones, Maria Garcia‐Maestre, Anna‐Carin Hägglund https://doi.org/10.1002/dvdy.707.By Christoffer Nord; Iwan Jones; Maria Garcia‐Maestre; Anna‐Carin Hägglund and Leif CarlssonReported by Author; Author; Author; Author; Author [Extracted from the article]

An experimental investigation was undertaken to determine the effects of moisture on the mechanical properties of vinylester resins (510A and 8084). The resins were exposed to seawater at 40°C and humid air at 50°C until the moisture content equilibrated. Both resins absorbed small amounts of moisture. Mechanical testing of both resins at dry and saturated conditions revealed very brittle behavior under tension and shear loading. The 8084 resin is more ductile than 510A at dry and saturated conditions. Moisture absorption was found to only slightly influence the mechanical response of these resins. Dry shear test specimens failed at quite low shear stresses in a resolved tensile mode and displayed sensitivity to the stress concentration in the losipescu shear specimen. Moisture absorption slightly enhanced ductility and reduced notch sensitivity which resulted in increased shear strength. POLYM. ENG. SCI., 53:2413-2421, 2013. © 2013 Society of Plastics Engineers, INTRODUCTION Vinylester resins have emerged as a promising alternative to epoxies and polyesters as matrix materials in composites used for marine applications. Vinylester resins cure at room temperature, are fire [...]