Easy regulation of chitosan-based hydrogel microstructure with citric acid as an efficient buffer.

Being an important soft material, the chitosan-based hydrogel exhibits colorful features and widespread applications stemmed mainly from its intrinsic microstructure. In particular, the design of hydrogels with oriented channel structures is of significance importance. In this paper, polyvinyl alcohol (PVA)/chitosan (CS)/MXene-CA hydrogels with directional channel structure were obtained by simple freezing and thawing method with citric acid (CA) as a buffer. The introduction of CS increased the tensile strength of PVA hydrogel from 5.38 kPa to 29.22 kPa. The uniform distribution of MXene was efficiently enhanced within the constructed channel microstructure, and conductivity was increased to 1.91 S/m. The response time of the flexible sensor based on the hydrogel was 200 ms. It can sensitively detect large-scale deformation (blending of joints), small-scale activity (frowning), and electrocardiogram. Therefore, the paper provided an efficient way to regulate the microstructure in hydrogel network and enhance the uniform dispersion of functional nanomaterials.

Insight into Steam Permeation through Perovskite Membrane via Transient Modeling.

A dynamic model based on BaCe0.9Y0.1O3-δ (BCY10) perovskite membrane for steam permeation process is presented here to essentially investigate the internal mechanism. The transient concentration distribution and flux of the charged species and the electric potential distribution within the membrane on the steam permeation process are analyzed in detail via simulation based on this model. The results indicate that the flux of steam can be improved via elevating operating temperatures, enlarging the difference of the partial steam pressure between two sides of the membrane, increasing the membrane density, and reducing the membrane thickness. Moreover, it was found that the polarization electric potential between both sides of the membrane occurs during the steam permeation process, especially at the steady state of the steam permeation process. The polarization electric potential reaches the maximum value at about 1050 K in this membrane. The evolution of electric potential can explain the influence of the above-mentioned factors on the steam permeation process. This study advances the mechanism of steam permeation through perovskite membrane, which provides a new strategy for the fundamental investigation of related species permeation (oxygen, carbon dioxide, hydrogen, etc.) on inorganic membranes via transient modeling.

Three Chiral Cyanide-Bridged Cr-Cu Complexes: Synthesis, Crystal Structures and Magnetic Properties.

Two trans-dicyanidochromium(III)-containing building blocks and one chiral copper(II) compound have been employed to assemble cyanide-bridged heterometallic complexes, resulting in three chiral cyanide-bridged Cr(III)-Cu(II) complexes, [Cu(L1)2Cr(L3)(CN)2]ClO42 · CH3OH · H2O (1a, L1 = (S,S)-1,2-diaminocyclohexane, H2L3 =1,2-bis(pyridine- 2-carboxamido)benzene), [Cu(L2)2Cr(L2)(CN)2]ClO42 · CH3OH · H2O (1b, L2 = (R,R)-1,2-diaminocyclohexane) [Cu(L3)2Cr(L4)(CN)2][Cr(L4)(CN)2] · CH3OH · 2H2O (2), (H2L4 = 1,2-bis(pyridine-2-carboxamido)-4-chlorobenzene). All the three complexes have been characterized by elemental analysis, IR spectroscopy and X-ray structure determination. Single-crystal X-ray diffraction analysis shows that the two enantiomeric complexes 1a, 1b and the complex 2 belong to cyanide-bridged cationic binuclear structure type with ClO4 - or the anionic cyanide building block as balance anion for complexes 1a, 1b or 2, respectively. Investigation of the magnetic properties of the complexes 1a and 2 reveals the weak ferromagnetic coupling between the neighboring Cr(III) and Cu(II) ions through the bridging cyanide group.

[Analysis on signaling pathway network of proliferation of neural stem cells].

Neural stem cells in brains have capacities of proliferation and differentiation, which is very critical to rebuild the cerebral cortex functions. Therefore, it is of great importance to find key targets and network pathways that regulate the proliferation of neural stem cells, which is also a pressing problem in the medical circle. With the Notch pathway as the core of the network, this paper summarized the advance of the bimolecular network system composed of Wnt, Shh, EGFR, cytokines and Notch signal, and analyzed such key nodes as Notch receptor, CBF1, NICD, Hesl, which may become potential targets of new-type drugs in the future. With the multi-component, multi-target, multi-lever characteristics, traditional Chinese medicines have many common grounds with the network pharmacology. The active component groups or active ingredients in traditional Chinese medicines are one of the material bases for showing their network pharmacological effect, which is worth exploring. This paper aims to provide a new strategy for the treatment of neurodegenerative disease and nerve injury with traditional Chinese medicines.

[Research on effect of Baimai powder effective compounds group promotes neurogenesis and maintains of neural stem cells after cerebral infarction].

The neural stem cells (NSCs), play a crucial role in stroke treatment, which can be regulated by a few of traditional Chinese medicines. In this study, the effect of the Mongolian medicine Baimai powder effective compounds group (BMECG) on the proliferation of NSCs has been investigated. The cultured NSCs which were isolated from newborn rat cerebral cortical in vitro were exposed to oxygen glucose deprivation/reoxgenation (OGD/R). The CFSE immunofluorescence staining was employed to identify the proliferation of NSCs by flow cytometry. Furthermore, the bilateral carotid artery occlusion (BCAO) was established on Kunming mice, and all groups were ig for 7 d respectively. The neurobehavioral changes was studied with rota-rod treadmill test, after that, the brain of mice were detected by immunohistochemistry with labeling of Nestin and pathological observation at 7 days after BCAO. It was found that, proliferation of NSCs was increased by BMECG in in vitro and in vivo. And BMECG significantly improved the time of staying in the rota-rod, it can promote the foundction of in cerebral cortex. It is concluded that these results further support the hypothesis that neuroprotective effect of BMECG may relate to the ability of stimulating self-renew of NSCs, which can be provided a new insight and strategy of anti-neuropathy of stroke.