8,682 research outputs found
Design and fabrication of robust broadband extreme ultraviolet multilayers
The random layer thickness variations can induce a great deformation of the
experimental reflection of broadband extreme ultraviolet multilayer. In order
to reduce this influence of random layer thickness fluctuations, the
multiobjective genetic algorithm has been improved and used in the robust
design of multilayer with a broad angular bandpass. The robust multilayer with
a lower sensitivity to random thickness errors have been obtained and the
corresponding multilayer mirrors were fabricated. The experimental results of
robust Mo/Si multilayer with a wide angular band were presented and analyzed,
and the advantage of robust multilayer design was demonstrated
Visible transparent, UV-blocking polymer nanocomposite films containing nano-sized organic-LDH (Layered Double Hydroxide) hybrid
A nano-sized Mg2Al layered double hydroxide (LDH) was used for encapsulating an organic UV absorber, 2-hydroxy-4- methoxybenzeophenone-5-sulfonic acid (HMBS), to produce HMBS@LDH hybrid nano-platelets. Upon dispersing this organic-inorganic hybrid LDH into ethylene-vinyl alcohol copolymer (EVOH) for film casting, a thin polymernanocomposite film that is UV opaque but highly transparent to visible light (higher than 90%) was formed. Thermogravimetry (TG) analysis confirmed that the intercalation of HMBS into LDH considerably increased the thermal stability of HMBS. Such an improvement was attributed to the strong guest-host interaction between the HMBS anions and the LDH layers. Also, the nanocomposite films were flexible and had good mechanical properties.<br /
Hand gesture recognition in complex background based on convolutional pose machine and fuzzy gaussian mixture models
© 2020, The Author(s). Hand gesture is one of the most intuitive and natural ways for human to communicate with computers, and it has been widely adopted in many human–computer interaction applications. However, it is still a challenging problem when confronted with complex background, illumination variation and occlusion in real-world scenarios. In this paper, a two-stage hand gesture recognition method is proposed to tackle these problems. At the first stage, hand pose estimation is developed to locate the hand keypoints using the convolutional pose machine, which can effectively localize hand keypoints even in a complex background. At the second stage, the Fuzzy Gaussian mixture models (FGMMs) are tailored to reject the nongesture patterns and classify the gestures based on the estimated hand keypoints. Extensive experiments are conducted to evaluate the performance of the proposed method, and the result demonstrates that the proposed algorithm is effective, robust, and satisfactory in real-time scenarios
Evaluation of chidamide and PFI-1 as a combination therapy for triple-negative breast cancer
Purpose: To evaluate the in vitro and in vivo effects of the combination therapy of histone deacetylases (HDAsC) inhibitor, chidamide, and bromodomain-containing proteins (BETs) inhibitor, PFI-1, on triplenegative breast cancer (TNBC).
Methods: Four distinct breast cancer cell lines and one TNBC mouse model were treated with vehicle, chidamide, PFI-1 alone, or chidamide and PFI-1. The inhibitory effect of chidamide or PFI-1 on HDACs and BETs was assessed by HDAC enzyme inhibition and AlphaScreen assays. Cell viability was determined by MTT assay while protein expression of p-STAT3 was evaluated by western blotting and immunohistochemistry (IHC) staining assay.
Results: Chidamide exerted inhibitory effect on HDACs while PFI-1 inhibited BET proteins. The threedimensional model demonstrated the interactions between chidamide and HDAC2, and between PFI-1 and BRD4. Chidamide or PFI-1 exerted inhibitory effects on breast cancer cell proliferation in vitro. However, the combination of PFI-1 and chidamide significantly inhibit MDA-MB-231 cell viability, and decrease the expression of p-STAT3, when compared to that treated with chidamide or PFI-1 alone. Moreover, the combined inhibitory effect of PFI-1 and chidamide on tumor growth was also found in the in vivo mice experiments.
Conclusion: The combination of chidamide and PFI-1 is a potential is a potential therapeutic strategy for the management of TNBC.
Keywords: Triple-negative breast cancer, Histone deacetylases, Bromodomai
PUMA amplifies necroptosis signaling by activating cytosolic DNA sensors.
Necroptosis, a form of regulated necrotic cell death, is governed by RIP1/RIP3-mediated activation of MLKL. However, the signaling process leading to necroptotic death remains to be elucidated. In this study, we found that PUMA, a proapoptotic BH3-only Bcl-2 family member, is transcriptionally activated in an RIP3/MLKL-dependent manner following induction of necroptosis. The induction of PUMA, which is mediated by autocrine TNF-α and enhanced NF-κB activity, contributes to necroptotic death in RIP3-expressing cells with caspases inhibited. On induction, PUMA promotes the cytosolic release of mitochondrial DNA and activation of the DNA sensors DAI/Zbp1 and STING, leading to enhanced RIP3 and MLKL phosphorylation in a positive feedback loop. Furthermore, deletion of PUMA partially rescues necroptosis-mediated developmental defects in FADD-deficient embryos. Collectively, our results reveal a signal amplification mechanism mediated by PUMA and cytosolic DNA sensors that is involved in TNF-driven necroptotic death in vitro and in vivo
Partial exfoliation of layered double hydroxides in DMSO : a route to transparent polymer nanocomposites
Layered double hydroxides (LDHs), either having nitrate counter anions or intercalated with organic molecules, have been for the first time partially exfoliated in dimethyl sulfoxide (DMSO) to form a transparent suspension. Atomic force microscopy (AFM) images showed that both the lateral size and the thickness of the LDH nanoplatelets were decreased after the exfoliation. The organic-LDHs maintained their intercalation characteristics, i.e. the thermal stability improvement of the incorporated organic anions, after the exfoliation in DMSO. Transparent ethylene-vinyl alcohol copolymer (EVOH) nanocomposite films containing partially exfoliated LDHs intercalated with UV absorbers were prepared using DMSO as the processing solvent. As the first reported example of a highly transparent LDH/polymer composite, the obtained composite film had a visible light transmittance of 90% (comparable to that of the pure matrix), was flexible and exhibited an excellent UV-shielding capability and thermal stability. <br /
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