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Background Aberrant hippocampal neurogenesis is an important pathological feature of sepsis-associated encephalopathy. In the current study, we examined the potential role of the long noncoding RNA (lncRNA) sex-determining region Y-box 2 (SOX2) overlapping transcript (SOX2OT), a known regulator of adult neurogenesis in sepsis-induced deficits in hippocampal neurogenesis and cognitive function. Methods Sepsis was induced in adult C57BL/6 J male mice by cecal ligation and perforation (CLP) surgery. Randomly selected CLP mice were transfected with short interfering RNAs (siRNAs) against SOX2OT or SOX2, or with scrambled control siRNA. Cognitive behavior was tested 8–12 days post-surgery using a Morris water maze. Western blotting and RT-qPCR were used to determine expression of SOX2, Ki67, doublecortin (DCX), nestin, brain lipid-binding protein, and glial fibrillary acidic protein (GFAP) in the hippocampus. The number of bromodeoxyuridine (BrdU)+/DCX+ cells, BrdU+/neuronal nuclei (NeuN)+ neurons, and BrdU+/GFAP+ glial cells in the dentate gyrus were assessed by immunofluorescence. Results CLP mice showed progressive increases in SOX2OT and SOX2 mRNA levels on days 3, 7, and 14 after CLP surgery, accompanied by impaired cognitive function. Sepsis led to decrease in all neuronal markers in the hippocampus, except GFAP. Immunofluorescence confirmed the decreased numbers of BrdU+/DCX+ cells and BrdU+/NeuN+ neurons, and increased numbers of BrdU+/GFAP+ cells. SOX2OT knockdown partially inhibited the effects of CLP on levels of SOX2 and neuronal markers, neuronal populations in the hippocampus, and cognitive function. SOX2 deficiency recapitulated the effects of SOX2OT knockdown. Conclusion SOX2OT knockdown improves sepsis-induced deficits in hippocampal neurogenesis and cognitive function by downregulating SOX2 in mice. Inhibiting SOX2OT/SOX2 signaling may be effective for treating or preventing neurodegeneration in sepsis-associated encephalopathy.

As one of the most investigated conducting polymers, polyaniline (PANI) is considered to be of practical use in many applications. In this study, two new ionic liquids, 1-methylimidazolium hydrogen sulfate ([Hmim]HSO4) and 1-methyl-3-n-butylimidazopersulfate ([C4mim]2S2O8), which were synthesized from 1-methylimidazole ([Hmim]), were used as solvent and dopant, oxidizer, respectively, for in situ polymerization of aniline. Because of the application of the unique structure of ionic liquid, we obtained the ionic liquid–doped polyaniline (IL-PANI) with high solubility (25 mg mL−1 in dimethyl sulfoxide (DMSO)). And by adjusting the ratio of [C4mim]2S2O8 to aniline monomer, the preferred PANI nanofibers could be controlled to form a three-dimensional porous structure. It was found that the ion/electron transport channels could be formed inside the 3D structure. Thus, the redox reactions could occur both at the surface and inside the PANI electrode. Electrochemical characterization showed that the fabricated PANI electrode exhibited a specific capacitance of 489 F g−1 at a current density of 0.5 A g−1. Also, the capacity retention rate reached up to 81% after 4000 cycles investigated at 2 A g−1. In addition, a high-energy density of 80.2 Wh kg−1 was measured when [Hmim]HSO4 was used as an electrolyte. Thus, the present work suggested a new strategy for fabricating high-performance PANI electrode for supercapacitor applications.

In this investigation, we described a facile preparation of temperature/photo dual sensitive polymers (PGABs) by Ugi four-component polymerization (Ugi-4CP) at room temperature in “one-pot” method using glutaraldehyde, 4-amido-azobenzene, t-butyl isocyanide and carboxyl-end-capped polyethylene glycols (S-PEG) as monomers. PGABs were found to be reversibly sensitive to the temperature in salt solution, and their lower critical solution temperatures (LCST) can be tuned to the range of 17.2–68.4 °C by changing the structure of PGABs, sort and concentration of salt. The configuration transition of PGABs between cis-form and trans-form was reversibly induced by the alternating radiation at 365 and 254 nm. The rate and conversion of isomerization showed a remarkable dependence on the chemical structure of PGAB. By the photosensitivity, the LCST of PGAB-800 is further regulated in 1.0 °C change because of the hydrophilicity difference of cis-trans-azobenzene moiety. Through the combination of the thermosensitivity and photosensitivity, the particles of PGABs with nano/μm dimension were successfully controlled by the light radiation and temperature change.

Three-dimensional (3D) nanostructured conducting polymer hydrogels represent a group of high-performance electrochemical energy-storage materials. Here, we demonstrate a molecular self-assembly approach toward controlled synthesis of nanostructured polypyrrole (PPy) conducting hydrogels, which was "cross-linked" by a conjugated dopant molecule trypan blue (TB) to form a 3D network with controlled morphology. The protonated TB by ion bonding aligns the free sulfonic acid groups into a certain spatial structure. The sulfonic acid group and the PPy chain are arranged by a self-sorting mechanism to form a PPy nanofiber structure by electrostatic interaction and hydrogen bonding. It is found that PPy hydrogels doped with varying dopant concentrations and changing dopant molecules exhibited controllable morphology and tunable electrochemical properties. In addition, the conjugated TB dopants promoted interchain charge transport, resulting in higher electrical conductivity (3.3 S/cm) and pseudocapacitance for the TB-doped PPy, compared with PPy synthesized without TB. When used as supercapacitor electrodes, the TB-doped PPy hydrogel reaches maximal specific capacitance of 649 F/g at the current density 1 A/g. The result shows that PPy nanostructured hydrogels can be tuned for potential applications in next-generation energy-storage materials.

Al–Mg alloy coatings were deposited onto superfine tungsten wire substrates via electron beam deposition at electronic beam currents ranging from 80 to 120 mA. The effects of electronic beam currents and baking process on the surface characteristics of the aluminium–magnesium alloy coatings were investigated using scanning electron microscopy. Energy-dispersive X-ray was also used to investigate the composition of the coatings according to the chemical components of the source materials. X-ray diffraction results suggested that the Al–Mg alloy coatings consisted of an Al12Mg17 intermetallic compound and pure aluminium phase. Electrochemical measurements determined the corrosion protection performance of the aluminium–magnesium alloy coatings with different magnesium contents. Specimen tensile properties were related to electron beams and surface roughness. The anti-corrosion performance of the coatings was increased with magnesium content.

We reported a facile self-generated sacrificial template method for fabricating mesoporous three dimension NiCo2O4/graphene electrode material. Nickel, cobalt, and zinc ions dissolved in ethylene glycol reacted with potassium hydroxide solution to co-deposit onto graphene at 140 °C under atmospheric environment. With further addition of potassium hydroxide, zinc hydroxide as a self-generated sacrificial template was dissolved in situ, leading to the formation of mesoporous morphology. Structure and morphology characteristics were determined by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and N2 adsorption experiments. Electrochemical properties were analyzed by AC impedance spectroscopy, cycling voltammetry, and charge/discharge test in 2 M KOH. Results showed that the as—prepared NiCo2O4/graphene electrode possessed a large specific surface area of 281.4 m2 g−1, an ultrahigh specific capacity of 1024.99 and 662.12 C g−1 at current density of 1 and 50 A g−1 respectively, and a long-term cycling life of 10,000 charge/discharge tests.

A facile synthesis approach was successfully developed to synthesize mesoporous NiCo2S4 in ethylene glycol. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and N2 adsorption–desorption experiment were conducted to examine the morphology and microstructure of the as-prepared NiCo2S4. Furthermore, electrochemical measurements, including cyclic voltammetry, galvanostatic charge–discharge tests, and electrochemical impedance spectroscopy, were carried out in a three-electrode system to evaluate the electrochemical properties of the mesoporous NiCo2S4. The as-prepared NiCo2S4 possessed a high specific surface area of 223.6 m2 g−1 with a high specific capacity of 406 C g−1 at 0.5 A g−1. In addition, only a 6.3 % loss of specific capacity was observed at 5 A g−1 after 20,000 GCD cycles, suggesting a long life cycle.

In this paper, a series of monomers (M1-M7) were facilely synthesized by Passerini reaction and the subsequent in-situ polymerization led to the formation of the conductive poly(indole/thiophene)s (P1-P7). Among P1-P7, it was found through the comparison that P7-P with a higher conjugated system exhibits an outstanding specific capacitance of 1170 F g−1 (scan rate 1 mV s−1), power density of 2614.4 W kg−1 and energy density of 56.5 Wh kg−1 (5 A g−1). The capacitance performance of P7-P complexed with Fe3+ system is further increased by 130 F g−1 because of the redox reaction of Fe3+. Using the chronoamperometry, the minimum detection limit of polymer P7-P for Fe3+ is 3 × 10−5 M. In summary, the facile synthesis of the conductive poly(indole/thiophene) polymers, their excellent energy storage and Fe3+ detection performance, open an opportunity for functional polymers in the energy storage and sensor applications.