Nanoimprinting Solution-Derived Barium Titanate for Electro-Optic Metasurfaces.

Electro-optic metasurfaces have demonstrated significant potential in enhancing the modulation speed and efficiency for fast and large-scale free-space optical devices. Barium titanate has a strong electro-optic Pockels coefficient, but its availability in thin-film form is restricted due to costly growth processes or low thickness. Here, we fabricated active metasurfaces using an etch-free bottom-up process with sol-gel-based polycrystalline barium titanate with a large electro-optic coefficient similar to bulk lithium niobate.

Sol-Gel Barium Titanate Nanohole Array as a Nonlinear Metasurface and a Photonic Crystal.

The quest of a nonlinear optical material that can be easily nanostructured over a large surface area is still ongoing. Here, we demonstrate a nanoimprinted nonlinear barium titanate 2D nanohole array that shows the optical properties of a 2D photonic crystal and a metasurface, depending on the direction of the optical axis. The challenge of nanostructuring the inert metal-oxide is resolved by direct soft nanoimprint lithography with sol-gel derived barium titanate enabling critical dimensions of 120 nm with aspect ratios of five.

Expression and distribution of laminin alpha1 and alpha2 chains in embryonic and adult mouse tissues: an immunochemical approach.

Protein levels, mRNA expression, and localization of laminin alpha1 and alpha2 chains in development and in adult mice were examined. Recombinant fragments were used to obtain high-titer-specific polyclonal antibodies for establishing quantitative radioimmuno-inhibition assays. This often demonstrated an abundance of alpha2 chain, but also distinct amounts of alpha1 chain for adult tissues.

Akt/PKB regulates laminin and collagen IV isotypes of the basement membrane.

Basement membranes are important for epithelial differentiation, cell survival, and normal and metastatic cell migration. Much is known about their breakdown and remodeling, yet their positive regulation is poorly understood. Our previous analysis of a fibroblast growth factor (FGF) receptor mutation raised the possibility that protein kinase B (Akt/PKB) activated by FGF is connected to the expression of certain laminin and type IV collagen isotypes.

Modulation of extracellular matrix adhesiveness by neurocan and identification of its molecular basis.

Neurocan is one of the major chondroitin sulfate proteoglycans of perinatal rodent brain. HEK-293 cells producing neurocan recombinantly show changes in their behavior. The expression of full-length neurocan led to a detachment of the secreting cells and the formation of floating spheroids.

Neonatal exposure to neurotoxic pesticides increases adult susceptibility: a review of current findings.

An environmental mischance commonly occuring in nature is the combination of neonatal exposure and later adult exposure to various toxic substances. During neonatal life, offspring can be affected by toxic agents either by transfer via mother's milk or by direct exposure. In many mammalian species the perinatal period is characterized by a rapid development of the brain--'the brain growth spurt' (BGS).

Differential expression of muscarinic subtype mRNAs after exposure to neurotoxic pesticides.

We have recently reported an increase in the density of muscarinic cholinergic receptors in mice neonatally exposed to a persistent environmental agent, dichlorodiphenyltrichloroethane (DDT), and a subsequent exposure as adults to nonpersistent toxicants, such as bioallethrin or paraoxon. Here we have examined the effects of an exposure like this on muscarinic receptor mRNA expression. Ten-day-old Naval Medical Research Institute mice received a single oral dose of DDT (0.

Changes in behavior and muscarinic receptor density after neonatal and adult exposure to bioallethrin.

Throughout life, mammals are exposed to environmental toxicants, some of which have acute effects on the nervous system. Early, low-dose exposure in combination with later re-exposure and possible interference with normal aging have been little studied. The present study revealed increased susceptibility in adult mice, exposed neonatally to a low dose of the insecticide bioallethrin, to renewed exposure to bioallethrin as adults.