Self-aligned, full solution process polymer field-effect transistor on flexible substrates

Conventional techniques to form selective surface energy regions on rigid inorganic substrates are not suitable for polymer interfaces due to sensitive and soft limitation of intrinsic polymer properties. Therefore, there is a strong demand for finding a novel and compatible method for polymeric surface energy modification. Here, by employing the confined photo-catalytic oxidation method, we successfully demonstrate full polymer filed-effect transistors fabricated through four-step spin-coating process on a flexible polymer substrate. The approach shows negligible etching effect on polymeric film. Even more, the insulating property of polymeric dielectric is not affected by the method, which is vital for polymer electronics. Finally, the self-aligned full polymer field-effect transistors on the flexible polymeric substrate are fabricated, showing good electrical properties and mechanical flexibility under bending tests

Photo-reactive charge trapping memory based on lanthanide complex

Traditional utilization of photo-induced excitons is popularly but restricted in the fields of photovoltaic devices as well as photodetectors, and efforts on broadening its function have always been attempted. However, rare reports are available on organic field effect transistor (OFET) memory employing photo-induced charges. Here, we demonstrate an OFET memory containing a novel organic lanthanide complex Eu(tta)<sub>3</sub> ppta (Eu(tta)<sub>3</sub> = Europium(III) thenoyltrifluoroacetonate, ppta = 2-phenyl-4,6-bis(pyrazol-1-yl)-1,3,5-triazine), in which the photo-induced charges can be successfully trapped and detrapped. The luminescent complex emits intense red emission upon ultraviolet (UV) light excitation and serves as a trapping element of holes injected from the pentacene semiconductor layer. Memory window can be significantly enlarged by light-assisted programming and erasing procedures, during which the photo-induced excitons in the semiconductor layer are separated by voltage bias. The enhancement of memory window is attributed to the increasing number of photo-induced excitons by the UV light. The charges are stored in this luminescent complex for at least 10<sup>4</sup>s after withdrawing voltage bias. The present study on photo-assisted novel memory may motivate the research on a new type of light tunable charge trapping photo-reactive memory devices

Low-Intensity Pulsed Ultrasound Stimulation Modulates the Nonlinear Dynamics of Local Field Potentials in Temporal Lobe Epilepsy

Low-intensity pulsed ultrasound stimulation (LIPUS) can inhibit seizures associated with temporal lobe epilepsy (TLE), which is the most common epileptic syndrome in adults and accounts for more than half of the cases of intractable epilepsy. Electroencephalography (EEG) signal analysis is an important method for studying epilepsy. The nonlinear dynamics of epileptic EEG signals can be used as biomarkers for the prediction and diagnosis of epilepsy. However, how ultrasound modulates the nonlinear dynamic characteristics of EEG signals in TLE is still unclear. Here, we used low-intensity pulsed ultrasound to stimulate the CA3 region of kainite (KA)-induced TLE mice, simultaneously recorded local field potentials (LFP) in the stimulation regions before, during, and after LIPUS. The nonlinear characteristics, including complexity, approximate entropy of different frequency bands, and Lyapunov exponent of the LFP, were calculated. Compared with the control group, the experimental group showed that LIPUS inhibited TLE seizure and the complexity, approximate entropy of the delta (0.5–4 Hz) and theta (4–8 Hz) frequency bands, and Lyapunov exponent of the LFP significantly increased in response to ultrasound stimulation. The values before ultrasound stimulation were higher ∼1.87 (complexity), ∼1.39 (approximate entropy of delta frequency bands), ∼1.13 (approximate entropy of theta frequency bands) and ∼1.46 times (Lyapunov exponent) than that after ultrasound stimulation (p < 0.05). The above results demonstrated that LIPUS can alter nonlinear dynamic characteristics and provide a basis for the application of ultrasound stimulation in the treatment of epilepsy

Current Status and Opportunities of Organic Thin-Film Transistor Technologies

Ajudes: National Key Research and Development Program of "Strategic Advanced Electronic Materials" under Grant 2016YFB0401100 and in part by the NSFC of China under Grant 61274083 and Grant 61334008.Attributed to its advantages of super mechanical flexibility, very low-temperature processing, and compatibility with low cost and high throughput manufacturing, organic thin-film transistor (OTFT) technology is able to bring electrical, mechanical, and industrial benefits to a wide range of new applications by activating nonflat surfaces with flexible displays, sensors, and other electronic functions. Despite both strong application demand and these significant technological advances, there is still a gap to be filled for OTFT technology to be widely commercially adopted. This paper providesa comprehensive reviewof the current status of OTFT technologies ranging from material, device, process, and integration, to design and system applications, and clarifies the real challenges behind to be addressed

Human Amniotic Fluid Stem Cell-Derived Exosomes as a Novel Cell-Free Therapy for Cutaneous Regeneration

Adult wound healing often results in fibrotic scarring that is caused by myofibroblast aggregation. Human amniotic fluid stem cells (hAFSCs) exhibit significantly anti-fibrotic scarring properties during wound healing. However, it is little known whether hAFSCs directly or indirectly (paracrine) contribute to this process. Using the full-thickness skin-wounded rats, we investigated the therapeutic potential of hAFSC-derived exosomes (hAFSC-exo). Our results showed that hAFSC-exo accelerated the wound healing rate and improved the regeneration of hair follicles, nerves, and vessels, as well as increased proliferation of cutaneous cells and the natural distribution of collagen during wound healing. Additionally, hAFSC-exo suppressed the excessive aggregation of myofibroblasts and the extracellular matrix. We identified several miRNAs, including let-7-5p, miR-22-3p, miR-27a-3p, miR-21-5p, and miR-23a-3p, that were presented in hAFSC-exo. The functional analysis demonstrated that these hAFSC-exo-miRNAs contribute to the inhibition of the transforming growth factor-β (TGF-β) signaling pathway by targeting the TGF-β receptor type I (TGF-βR1) and TGF-β receptor type II (TGF-βR2). The reduction of TGF-βR1 and TGF-βR2 expression induced by hAFSC-exo was also confirmed in the healing tissue. Finally, using mimics of miRNAs, we found that hAFSC-exo-miRNAs were essential for myofibroblast suppression during the TGF-β1-induced human dermal fibroblast-to-myofibroblast transition in vitro. In summary, this study is the first to show that exosomal miRNAs used in hAFSC-based therapy inhibit myofibroblast differentiation. Our study suggests that hAFSC-exo may represent a strategic tool for suppressing fibrotic scarring during wound healing

Reasons of Singles for Being Single:Evidence from Brazil, China, Czech Republic, Greece, Hungary, India, Japan and the UK

The current research aimed to examine the reasons people are single, that is, not in an intimate relationship, across eight different countries—Brazil, China, Czech Republic, Greece, Hungary, India, Japan, and the UK. We asked a large cross-cultural sample of single participants (N = 6,822) to rate 92 different possible reasons for being single. These reasons were classified into 12 factors, including one’s perceived inability to find the right partner, the perception that one is not good at flirting, and the desire to focus on one’s career. Significant sex and age effects were found for most factors. The extracted factors were further classified into three separate domains: Perceived poor capacity to attract mates, desiring the freedom of choice, and currently being in between relationships. The domain structure, the relative importance of each factor and domain, as well as sex and age effects were relatively consistent across countries. There were also important differences however, including the differing effect sizes of sex and age effects between countries

Ultra-broadband and tunable infrared absorber based on VO2 hybrid multi-layer nanostructure

We propose an ultra-broadband near- to mid-infrared (NMIR) tunable absorber based on VO2 hybrid multi-layer nanostructure by hybrid integration of the upper and the lower parts. The upper part is composed of VO2 nanocylinder arrays prepared on the front illuminated surface of quartz substrate, and VO2 square films and VO2/SiO2/VO2 square nanopillar arrays prepared on the back surface. The lower part is an array of SiO2/Ti/VO2 nanopillars on Ti substrate. The effects of different structural parameters and temperature on the absorption spectra were analyzed by the finite-difference time-domain method. An average absorption rate of up to 94.7% and an ultra-wide bandwidth of 6.5 μm were achieved in NMIR 1.5–8 μm. Neither vertical incident light with different polarization angles nor large inclination incident light has a significant effect on the absorption performance of the absorber. The ultra-broadband high absorption performance of this absorber will be widely used in NMIR photodetectors and other new optoelectronic devices