Deuterium has been recognized as an irreplaceable element
in industrial
and scientific research. However, hydrogen isotope separation still
remains a huge challenge due to the identical physicochemical properties
of the isotopes. In this paper, a partially fluorinated metal–organic
framework (MOF) with copper, a so-called FMOFCu, was investigated
to determine the separation efficiency and capacity of the framework
for deuterium extraction from a hydrogen isotope mixture. The unique
structure of this porous material consists of a trimodal pore system
with large tubular cavities connected through a smaller cavity with
bottleneck apertures with a size of 3.6 Å plus a third hidden
cavity connected by an even smaller aperture of 2.5 Å. Depending
on the temperature, these two apertures show a gate-opening effect
and the cavities get successively accessible for hydrogen with increasing
temperature. Thermal desorption spectroscopy (TDS) measurements indicate
that the locally flexible MOF can separate D2 from anisotope
mixture efficiently, with a selectivity of 14 at 25 K and 4 at 77
K.
Activated hepatic stellate cells (HSCs) play a key role in liver fibrosis, and inactivating HSCs has been considered a promising therapeutic approach. We previously showed that albumin and its derivative designed for stellate cell-targeting, retinol-binding protein–albumin domain III fusion protein (referred to as R-III), inactivate cultured HSCs. Here, we investigated the mechanism of action of albumin/R-III in HSCs and examined the anti-fibrotic potential of R-III in vivo. R-III treatment and albumin expression downregulated retinoic acid (RA) signaling which was involved in HSC activation. RA receptor agonist and retinaldehyde dehydrogenase overexpression abolished the anti-fibrotic effect of R-III and albumin, respectively. R-III uptake into cultured HSCs was significantly decreased by siRNA-STRA6, and injected R-III was localized predominantly in HSCs in liver. Importantly, R-III administration reduced CCl4- and bile duct ligation-induced liver fibrosis. R-III also exhibited a preventive effect against CCl4-inducd liver fibrosis. These findings suggest that the anti-fibrotic effect of albumin/R-III is, at least in part, mediated by downregulation of RA signaling and that R-III is a good candidate as a novel anti-fibrotic drug.
Hardware-based spiking neural networks (SNNs) to mimic biological neurons have been reported. However, conventional neuron circuits in SNNs have a large area and high power consumption. In this work, a split-gate floating-body positive feedback (PF) device with a charge trapping capability is proposed as a new neuron device that imitates the integrate-and-fire function. Because of the PF characteristic, the subthreshold swing (SS) of the device is less than 0.04 mV/dec. The super-steep SS of the device leads to a low energy consumption of ∼0.25 pJ/spike for a neuron circuit (PF neuron) with the PF device, which is ∼100 times smaller than that of a conventional neuron circuit. The charge storage properties of the device mimic the integrate function of biological neurons without a large membrane capacitor, reducing the PF neuron area by about 17 times compared to that of a conventional neuron. We demonstrate the successful operation of a dense multiple PF neuron system with reset and lateral inhibition using a common self-controller in a neuron layer through simulation. With the multiple PF neuron system and the synapse array, on-line unsupervised pattern learning and recognition are successfully performed to demonstrate the feasibility of our PF device in a neural network.
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