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The effect of visible light irradiation on the expression of pluripotent genes (Oct-4, Sox2, and Nanog) in amniotic fluid-derived stem cells (AFSCs) and on the osteogenic differentiation ability of AFSCs was investigated using light-emitting diodes (LEDs) at 0-2 mW/cm(2) in various wavelengths: [blue (470 nm), green (525 nm), yellow (600 nm), and red (630 nm)]. Pluripotent gene expression in AFSCs was up-regulated by visible light irradiation from a LED for more than 6 h. Green light irradiation of AFSCs up-regulated the expression of pluripotent genes more significantly than irradiation with other light. The osteogenic differentiation of AFSCs was facilitated by green and blue light irradiation. Facilitated differentiation into osteogenic cells by visible light irradiation was not mediated by reactive oxygen species (ROS); alkaline phosphatase activity (a marker of early osteogenic differentiation) and gene expression of osteopontin (a marker of late osteogenic differentiation) did not change significantly between AFSCs in differentiation medium with or without a ROS scavenger (vitamin C). The mitogen-activated protein kinase/extracellular signal-regulated protein kinase pathway, as well as other unknown signaling pathways, may be responsible for the activation of signaling pathways that facilitate the differentiation of AFSCs into osteogenic cells on light irradiation.

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This study performs surface reduction treatments, including hydrogen plasma treatment and rapid thermal anneal (RTA) in hydrogen ambient, to reduce the nitrogen content in the surface layer of the TaNx ultrathin film deposited by plasma-enhanced atomic layer deposition (PE-ALD). A four-point bend delamination test and a pull-off tensile test are used to study the interfacial strength of the PE-ALD thin film with copper. According to X-ray photoelectron spectroscopy and Auger electron spectroscopy, a new chemical phase with a very small nitrogen content, possibly β-TaNx , is formed on the PE-ALD TaNx thin film after the RTA treatment. The increase in the Ta/N atomic ratio in the RTA-treated TaNx thin film significantly improves the adhesion of the TaNx film with the sputter-deposited Cu layer. However, the hydrogen-plasma-treated TaNx thin film shows a slight decrease in nitrogen content but still demonstrates better adhesion with the Cu layer compared with the as-deposited one. While the Cu overlayer on the RTA-treated PE-ALD TaNx thin film can sustain the thermal anneal at 600°C , the one on the as-deposited TaNx thin film exhibits voiding even at a temperature as low as 400°C .

An image-based control strategy along with estimation of target motion is developed to track dynamic targets without motion constraints. To the best of our knowledge, this is the first work that utilizes a bounding box as image features for tracking control and estimation of dynamic target without motion constraint. The features generated from a You-Only-Look-Once (YOLO) deep neural network can relax the assumption of continuous availability of the feature points in most literature and minimize the gap for applications. The challenges are that the motion pattern of the target is unknown and modeling its dynamics is infeasible. To resolve these issues, the dynamics of the target is modeled by a constant-velocity model and is employed as a process model in the Unscented Kalman Filter (UKF), but process noise is uncertain and sensitive to system instability. To ensure convergence of the estimate error, the noise covariance matrix is estimated according to history data within a moving window. The estimated motion from the UKF is implemented as a feedforward term in the developed controller, so that tracking performance is enhanced. Simulations are demonstrated to verify the efficacy of the developed estimator and controller.

The affinity of a T cell receptor (TCR) binding to peptide:MHC profoundly impacts the phenotype and function of effector and memory cell differentiation. Little is known about the effect of low affinity priming on memory cell generation and function, which is particularly important in heterologous immunity, when microbe-specific T cells cross-react with allogeneic antigen and mediate graft rejection. We found that low affinity primed memory CD8+ T cells produced high levels of TNF ex vivo in response to heterologous rechallenge compared to high affinity primed memory T cells. Low affinity secondary effectors significantly upregulated TNFR2 on the cell surface and contained a higher frequency of TNFR2hi proliferating cells. Low affinity primed secondary effectors concurrently downregulated TNF production. Importantly, blockade of TNFR2 attenuated graft rejection in low but not high affinity primed animals. These data establish a functional connection between TNF signaling and TCR priming affinity and have implications for the immunomodulation of pathogenic T cell responses during transplantation.

Abstract— Two monodisperse polystyrene microspheres, 2.76 and 9.25 μm in diameter, were prepared by dispersion polymerization in an ethanol/iso‐propanol/water media. 2,2′‐azobis(isobutyronitrile) (AIBN) and poly(acrylic acid) (PAA) were utilized as the initiator and steric stabilizer, respectively. Optical properties including total transmittance (T%) and transmittance haze (H%) were determined when these two monodisperse polystyrene microspheres were applied as diffusive agents. This paper mainly discusses (1) different particle‐size effects and its hybrid behavior, (2) different thicknesses for the diffusion‐layer effect, and (3) the effects of diffusion‐layer arrangement and direction of incident light on the total transmittance (T%) and transmittance haze (H%).