[Research advances in the role of Rab GTPases in Alzheimer's disease].

Extracellular deposition of ß-amyloid (Aß) and intracellular hyperphosphorylated tau are the predominant pathological changes in Alzheimer's disease (AD). Increasing evidence demonstrates a critical role of a variety of small GTPases, namely Ras-related proteins (Rabs), in the pathogenesis of AD. As crucial regulators of intracellular membrane trafficking, alteration in Rab protein expression and function represents one of the primary factors contributing to the abnormal membrane trafficking in AD. Additionally, the Rab GTPases are also involved in the development of Aß, tau and other pathological changes associated with AD. In this article, we conduct a comprehensive review on the primary functions of multiple Rab proteins and their involvement in the pathogenesis of AD.

Efficient Halftoning via Deep Reinforcement Learning.

Halftoning aims to reproduce a continuous-tone image with pixels whose intensities are constrained to two discrete levels. This technique has been deployed on every printer, and the majority of them adopt fast methods (e.g., ordered dithering, error diffusion) that fail to render structural details, which determine halftone's quality. Other prior methods of pursuing visual pleasure by searching for the optimal halftone solution, on the contrary, suffer from their high computational cost. In this paper, we propose a fast and structure-aware halftoning method via a data-driven approach. Specifically, we formulate halftoning as a reinforcement learning problem, in which each binary pixel's value is regarded as an action chosen by a virtual agent with a shared fully convolutional neural network (CNN) policy. In the offline phase, an effective gradient estimator is utilized to train the agents in producing high-quality halftones in one action step. Then, halftones can be generated online by one fast CNN inference. Besides, we propose a novel anisotropy suppressing loss function, which brings the desirable blue-noise property. Finally, we find that optimizing SSIM could result in holes in flat areas, which can be avoided by weighting the metric with the contone's contrast map. Experiments show that our framework can effectively train a light-weight CNN, which is 15x faster than previous structure-aware methods, to generate blue-noise halftones with satisfactory visual quality. We also present a prototype of deep multitoning to demonstrate the extensibility of our method.

Mice with the Rab10 T73V mutation exhibit anxiety-like behavior and alteration of neuronal functions in the striatum.

Hyperphosphorylated Rab10 has been implicated in the pathogenesis of neurodegenerative diseases, such as Parkinson's disease and Alzheimer's disease. However, the neurophysiological function of the evolutionarily conserved Thr73 phosphorylation of Rab10 remains poorly understood. Here, we generated a novel mouse model expressing the non-phosphorylatable T73V mutation of Rab10 and performed a comprehensive series of neurological analyses, including behavioral tests, synaptic evaluations, neuronal and glial staining, assessments of neurite arborization and spine morphogenesis. The Rab10 T73V mutantmice exhibited a characteristic anxiety-like phenotype with other behavioral modules relatively unaffected. Moreover, Rab10 T73V mutant mice displayed striatum-specific synaptic dysfunction, as indicated by aberrantly increased expression levels of synaptic proteins and impaired frequencies of miniature inhibitory postsynaptic currents. The genetic deletion of Rab10 phosphorylation enhanced neurite arborization and accelerated spine maturation in striatal medium spiny neurons. Our findings emphasize the specific role of intrinsic phospho-Rab10 in the regulation of the striatal circuitry and its related behaviors.

Melting Behaviors of Bio-Based Poly(propylene 2,5-furan dicarboxylate)-b-poly(ethylene glycol) Co Polymers Related to Their Crystal Morphology.

In this experiment, a series of poly(propylene 2,5-furan dicarboxylate)-b-poly(ethylene glycol) (PPFEG) copolymers with different ratios were synthesized using melt polycondensation of dimethylfuran-2,5-dicarboxylate (DMFD), 1,3-propanediol (PDO) and poly(ethylene glycol) (PEG). The effect of PEG content on the crystallization behavior of the poly(propylene 2,5-furan dicarboxylate) (PPF) copolymers was investigated. For PPF, the nucleation density of the ß-crystals was higher than that of α-crystals. As Tc increases, the ß crystals are suppressed more, but at Tc = 140 °C, the bulk of PPF has already been converted to α crystals, which crystallize faster at higher nucleation densities, resulting in a difference in polymer properties. For this case, we chose to add a soft segment material, PEG, which led to an early multi-melt crystallization behavior of the PPF. The addition of PEG led to a decrease in the crystallization temperature of PPF, as well as a decrease in the cold crystallization peak of PPF. From the crystalline morphology, it can be seen that the addition of PEG caused the transformation of the PPF crystalline form to occur earlier. From the crystalline morphology of PPF at 155 °C, it can be observed that the ring-banded spherical crystals of the PPF appear slowly with increasing time. With the addition of PEG, spherical crystals of the ring band appeared earlier, and even appeared first, and then disappeared slowly.