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Geometrical cues in the extracellular environment are essential for cells guiding. Conventional fabrications for well-defined microstructures are usually associated with expensive and time-consuming micro-electro-mechanical systems (MEMS), including lithography and etching. Additionally, the microstructures produced on silicon wafers are not amendable after molding, hindering the applicability. Here, we developed a low-cost and efficient fabrication process to generate highly ordered microstructures for cell culture by designing and fabricating a tunable wrinkled on biocompatible polydimethylsiloxane (PDMS) surfaces based on different mechanical properties of the biomaterials. The mechanical properties, including Young's modulus, tensile strength, and thickness ratio between the stiff and soft bilayers, can be determined by the thickness of PDMS film, curing temperature, UV exposure time, applied strain rates during the fabrication, leading to various amplitudes and wavelengths of the wrinkled topography on polymeric materials. Those wrinkled surfaces with micro-pattern are further applied to hCMEC/D cell culture, an immortalized human cerebral microvascular endothelial cell line, to induce cell proliferation and provide guidance for cell arrangement and migration. Therefore, this report sheds light on cell biology and biomedical tissue engineering by delivering an affordable and tunable fabrication process for wrinkles formations on the polymeric thin film.

Strontium zirconate nickelate [(SZN); Sr0.69Ni0.47Zr0.085O3.75] was synthesized through a sol-gel method by adding nickel (II) acetylacetone instead of titanium isopropoxide, which can effectively make thin films smoother and further act as gate insulators applied in pentacene-based thin-film transistors. Sol-gel SZN thin films were investigated by X-ray photoelectron spectroscopy and atomic force microscopy to confirm the chemical composition and smooth surface roughness, and the latter property was found to be compatible for pentacene thin film growth. Thus, the electrical characteristics of pentacene-based transistors exhibited a high mobility of 10.04 cm2 V-1s-1 low threshold voltage of -1.51 V,, and low subthreshold swing slope of 350 mV/decade. To realize high mobility mechanisms, intermolecular coupling and reorganization energy of pentacene thin films were introduced. Another purpose of this introduction was to evaluate the higher hopping rate of carriers between the adjacent pentacene molecules on SZN derived from the March-Hush equation than other high-κ traditional sol-gel insulators.

Several new indolyl secondary phosphine oxides (SPOs), C8H6N–P( O)(H)(tBu) (4a′), MeC8H5N–P( O)(H)(tBu) (4b′), and PhC8H5N–P( O)(H)(tBu) (4c′), were prepared from the reactions of corresponding 1H-indoles with PtBuCl2 and hydrolysis followed. Further reaction of 4a′, a tautomeric form of C8H6N–P(OH)(tBu) (4a), with Pd(COD)Cl2 yielded a di-palladium complex, [(4a)(4a-H+)Pd(μ-Cl)]2 (6a). Crystal structures of PhC8H5N–P(Cl)(tBu) (3c), (4c′) and (6a) were determined by single-crystal X-ray diffraction methods. The stability of this type of SPO is presumably caused by the indolyl scaffold. In addition, SPOs are air- and moisture-stable preligands and are advantageous for the purpose of storage. In this work, these SPO ligands were employed in the Suzuki–Miyaura cross-coupling reactions as catalytic precursors. This catalytic condition has been tolerated to a variety of functional groups and the coupling reactions underwent efficiently with the arylbromides and arylchlorides, respectively.

In this study, we investigated whether stress can enhance the toxicity of oligomer Abeta(1-40) in the mouse brain. Stress was applied to the animals, consisting of a 2-day inescapable foot shock followed by 3-weekly situation reminders (SRs). We found that stress significantly affected not only the amygdala-dependent (anxiety) but also the hippocampal-dependent (spatial learning and memory) behaviors through the oxidative damage caused in these two regions. However, oligomer Abeta(1-40) treatment alone did not induce behavioral impairment. In addition, combined oligomer Abeta(1-40) and stress treatment increased the glucocorticoid receptor (GR)/mineralocorticoid receptor (MR) ratio and the expression of corticotrophin releasing factor 1 (CRF-1) receptor in the hippocampus. Changes in the components of the hypothalamic-pituitary-adrenal (HPA) axis, such as the GR/MR ratio and CRF-1 level, were observed, accompanied by increasing Abeta accumulation, oxidative stress, nuclear transcription factor (NF-kappaB) hypoactivity, and apoptotic signaling in the hippocampus, and decreasing calbindin D28K and NMDA receptor 2A/2B (NR2A/2B) in the hippocampus, along with alteration of the cholinergic neurons (ChAT) in the medium septum/diagnoid band (MS/DB), noradrenergic neurons (TH) in the locus coeruleus (LC), and serotonergic neurons (5-HT) in the Raphe nucleus. Therefore, apoptosis and synaptic dysfunction in the hippocampus severely induced the impairment of spatial learning and memory. These results suggest that stress may play an important role in the early stages of Alzheimer's disease (AD), and an antioxidant strategy might be a potential therapeutic approach for stress-mediated disorders.

Pentacene-based organic thin-film transistors (TFTs) with solution-processed barium zirconate titanate as gate dielectrics are studied. The fabricated TFTs show a high field-effect mobility of 7.31 cm2 · V-1 · s-1 at a VG of -3.6 V, a low threshold voltage of -1.60 V, and a low subthreshold slope swing of 162 mV/dec. Moreover, organic inverters with enhancement-mode load and driver are also investigated. The inverters demonstrate a high gain of 9.98, a low operating voltage of -5 V, and a low power dissipation of 1.14 μW. Very good agreements between simulation and experimental results are achieved.