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Abstract This paper investigates an intelligent reflecting surface (IRS) assisted downlink short packet transmission system, where an access point sends short packets to multiple devices with the help of an IRS. Specifically, a performance comparison between the frequency division multiple access and time division multiple access is conducted for the considered system, from the perspective of average age of information (AoI). To minimize the maximum average AoI among all devices, the resource allocation and passive beamforming are jointly optimized. However, the formulated problem is difficult to solve due to the non‐convex objective function and coupled variables. Thus, an alternating optimization based algorithm is proposed by exploiting the semidefinite relaxation and bisection search techniques. Simulation results show that time division multiple access can achieve lower AoI by exploiting the time‐selective passive beamforming of IRS for maximizing the signal to noise ratio of each device consecutively. Moreover, it also shows that as the length of information bits becomes sufficiently large as compared to the available bandwidth, the proposed frequency division multiple access transmission scheme becomes more favourable due to more flexible power allocation.

Abstract The quiescent/slow‐cycling state preserves the self‐renewal capacity of cancer stem cells (CSCs) and leads to the therapy resistance of CSCs. The mechanisms maintaining CSCs quiescence remain largely unknown. Here, it is demonstrated that lower expression of MAN1A1 in glioma stem cell (GSC) resulted in the formation of high‐mannose type N‐glycan on CD133. Furthermore, the high‐mannose type N‐glycan of CD133 is necessary for its interaction with DNMT1. Activation of p21 and p27 by the CD133–DNMT1 interaction maintains the slow‐cycling state of GSC, and promotes chemotherapy resistance and tumorigenesis of GSCs. Elimination of the CD133–DNMT1 interaction by a cell‐penetrating peptide or MAN1A1 overexpression inhibits the tumorigenesis of GSCs and increases the sensitivity of GSCs to temozolomide. Analysis of glioma samples reveals that the levels of high‐mannose type N‐glycan are correlated with glioma recurrence. Collectively, the high mannose CD133–DNMT1 interaction maintains the slow‐cycling state and tumorigenic potential of GSC, providing a potential strategy to eliminate quiescent GSCs.

Serum α-fetoprotein- (AFP-) elevated gastric cancer is a rare tumor that has a poor prognosis due to high incidence of liver metastasis. This study sought to investigate the optimal treatment modality. A total of 319 gastric cancer patients with liver metastasis (GCLM) whose serum AFP levels were tested before treatment were enrolled in this study. They were classified as the serum AFP ≥ 20 ng/ml group (n=74) and the AFP

There has been renewed interest in using mitochondrial uncoupler compounds such as niclosamide and carbonyl cyanide p‐(trifluoromethoxy)phenylhydrazone (FCCP) for the treatment of obesity, hepatosteatosis and diseases where oxidative stress plays a role. However, both FCCP and niclosamide have undesirable effects that are not due to mitochondrial uncoupling, such as inhibition of mitochondrial oxygen consumption by FCCP and induction of DNA damage by niclosamide. Through structure–activity analysis, we identified FCCP analogues that do not inhibit mitochondrial oxygen consumption but still provided good, although less potent, uncoupling activity. We also characterized the functional role of the niclosamide 4′‐nitro group, the phenolic hydroxy group and the anilide amino group in mediating uncoupling activity. Our structural investigations provide important information that will aid further drug development.

Abstract The recent emergence of non‐fullerene acceptors (NFAs) has energized the field of organic photodiodes (OPDs) and made major breakthroughs in their critical photoelectric characteristics. Yet, stabilizing inverted NF‐OPDs remains challenging because of the intrinsic degradation induced by improper interfaces. Herein, a tin ion‐chelated polyethyleneimine ethoxylated (denoted as PEIE‐Sn) is proposed as a generic cathode interfacial layer (CIL) of NF‐OPDs. The chelation between tin ions and nitrogen/oxygen atoms in PEIE‐Sn contributes to the interface compatibility with efficient NFAs. The PEIE‐Sn can effectively endow the devices with optimized cascade alignment and reduced interface defects. Consequently, the PEIE‐Sn‐OPD exhibits properties of anti‐environmental interference, suppressed dark current, and accelerated interfacial electron extraction and transmission. As a result, the unencapsulated PEIE‐Sn‐OPD delivers high specific detection and fast response speed and shows only slight attenuation in photoelectric performance after exposure to air, light, and heat. Its superior performance outperforms the incumbent typical counterparts (ZnO, SnO2, and PEIE as the CILs) from metrics of both stability and photoelectric characteristics. This finding suggests a promising strategy for stabilizing NF‐OPDs by designing appropriate interface layers.

Tendons are an important part of the musculoskeletal system. Connecting muscles to bones, tendons convert force into movement. Tendon injury can be acute or chronic. Noticeably, tendon healing requires a long time span and includes inflammation, proliferation, and remodeling processes. The mismatch between endogenous and exogenous healing may lead to adhesion causing further negative effects. Management of tendon injuries and complications such as subsequent adhesion formation are still challenges for clinicians. Due to numerous factors, tendon healing is a complex process. This review introduces the role of various biological and mechanical factors and epigenetic regulation processes involved in tendon healing.

Artificial visual electronics that mimic the structure and function of human eyes can be a powerful tool to provide visual feedback in the closed‐loop sensation/action systems, which can be beneficial to achieve sophisticated functions in a precise and efficient way. Herein, how artificial visual electronics work in the closed‐loop sensation/action systems, mimicking the human eyes for human behaviors, followed by how artificial visual electronics are utilized in various fields are introduced. To fully mimic the human eyes, how to achieve the structural similarity of artificial visual electronics with eyeballs is highlighted, and focused on the key component, i.e., retina‐like 3D light‐detecting imagers. When combined with the machine‐learning method, such retina‐like 3D imagers are expected to significantly benefit the closed‐loop sensation/action systems.

Friction during the hot extrusion of Inconel 625 superalloy tubes causes severe wear of the mold and plays a decisive role in the quality of the workpieces. In this paper, a ball-to-disk method was utilized to investigate the tribological behavior of Inconel 625 using two different tribological pairs, i.e., GCr15 and Si3N4, at room and elevated temperatures. Friction coefficient, specific wear rate, and morphology of worn surfaces were systematically characterized. It was found that the friction coefficients for both tribological pairs generally increased as the testing temperature increased, while the specific wear rate increased firstly and then decreased with the rise of temperature. Along with the increasing sliding speed, the friction coefficient between Inconel 625 and Si3N4 decreased monotonically, while the specific wear rate increased firstly and then decreased. Under any given testing condition, the friction coefficient and specific wear rate of the Inconel 625 for Inconel/Si3N4 pair are less than those of the Inconel/GCr15 pair. The main wear mechanisms between GCr15 and Inconel 625 are adhesive and fatigue wear at all testing temperatures. The wear mechanisms between Si3N4 and Inconel 625 are adhesive and abrasive wear at room temperature but fatigue wear at 500°C. Our findings indicate that the use of ceramic molds in the hot extrusion of Inconel 625 may significantly improve the surface qualities of the product and reduce the wear of the mold.

Background. Since circulating tumor DNA (ctDNA) offers clear advantages as a minimally invasive method for tumor monitoring compared with tumor tissue, we aimed to evaluate genotyping ctDNA using a next-generation sequencing- (NGS-) based panel to identify the prognostic value of mutation status in metastatic colorectal cancer (mCRC) patients with primary tumor resected and with subsequent lines of treatment in this study. Methods. 76 mCRC patients treated in Beijing Chao-Yang Hospital from 2011 to 2017 were enrolled. Genotyping of RAS/BRAF in tumor tissue and ctDNA was determined by ARMS PCR and with a 40-gene panel using NGS, respectively. Patient clinicopathologic features and RAS/BRAF gene mutation status were evaluated by survival analysis for disease-free survival (DFS) and progression-free survival (PFS). Results. Among 76 patients, KRAS distributions were not significantly correlated with any clinicopathologic features. The concordance between tumor tissue and ctDNA KRAS mutation was 81.25%. Mutations of RAS/BRAF had no significant impact on DFS after surgery (hazard ratio (HR), 1.205; 95% CI, 0.618 to 2.349; P=0.5837) but prognosticated poorer PFS in subsequent first-line therapy (HR, 3.351; 95% CI, 1.172 to 9.576; P=0.024). Conclusion. ctDNA was comparable with tumor tissue for mutation detection. RAS/BRAF mutations detected in ctDNA predict a worse PFS in mCRC patients with first-line chemotherapy. Our results provide support for the prognostic value of RAS/BRAF ctDNA mutation detection in mCRC patients.

Background and Objective. This study investigated the effects and underlying mechanisms of azithromycin (AZM) treatment on the osteogenic differentiation of human periodontal ligament stem cells (PDLSCs) after their stimulation with TNF-α in vitro. Methods. PDLSCs were isolated from periodontal ligaments from extracted teeth, and MTS assay was used to evaluate whether AZM and TNF-α had toxic effects on PDLSCs viability and proliferation. After stimulating PDLSCs with TNF-α and AZM, we analyzed alkaline phosphatase staining, alkaline phosphatase activity, and alizarin red staining to detect osteogenic differentiation. Real-time quantitative polymerase chain reaction (RT-qPCR) analysis was performed to detect the mRNA expression of osteogenic-related genes, including RUNX2, OCN, and BSP. Western blotting was used to measure the NF-κB signaling pathway proteins p65, phosphorylated p65, IκB-α, phosphorylated IκB-α, and β-catenin as well as the apoptosis-related proteins caspase-8 and caspase-3. Annexin V assay was used to detect PDLSCs apoptosis. Results. TNF-α stimulation of PDLSCs decreased alkaline phosphatase and alizarin red staining, alkaline phosphatase activity, and mRNA expression of RUNX2, OCN, and BSP in osteogenic-conditioned medium. AZM enhanced the osteogenic differentiation of PDLSCs that were stimulated with TNF-α. Western blot analysis showed that β-catenin, phosphorated p65, and phosphorylated IκB-α protein expression decreased in PDLSCs treated with AZM. In addition, pretreatment of PDLSCs with AZM (10 μg/ml, 20 μg/ml) prevented TNF-α-induced apoptosis by decreasing caspase-8 and caspase-3 expression. Conclusions. Our results showed that AZM promotes PDLSCs osteogenic differentiation in an inflammatory microenvironment by inhibiting the WNT and NF-κB signaling pathways and by suppressing TNF-α-induced apoptosis. This suggests that AZM has potential as a clinical therapeutic for periodontitis.

This paper presents tunneling field-effect transistor (TFET) with dual source regions. It explores the physics of drive current enhancement. The novel approach of dual source provides an effective technique for enhancing the drive current. It is found that this structure can offer four tunneling junctions by increasing a source region. Meanwhile, the dual source structure does not influence the excellent features of threshold slope (SS) of TFET. The number of the electrons and holes would be doubled by going through the tunneling junctions on the original basis. The overlap length of gate-source is also studied. The dependence of gate-drain capacitance Cgd and gate-source capacitance Cgs on gate-to-source voltage Vgs and drain-to-source voltage Vds was further investigated. There are simulation setups and methodology used for the dual source TFET (DS-TFET) assessment, including delay time, total energy per operation, and energy-delay product. It is confirmed that the proposed TFET has strong potentials for VLSI.

We demonstrate the impact of semiconductor/oxide interface traps (ITs) on the DC and AC characteristics of tunnel field-effect transistors (TFETs). Using the Sentaurus simulation tools, we show the impacts of trap density distribution and trap type on the n-type double gate- (DG-) TFET. The results show that the donor-type and acceptor-type ITs have the great influence on DC characteristic at midgap. Donor-like and acceptor-like ITs have different mechanism of the turn-on characteristics. The flat band shift changes obviously and differently in the AC analysis, which results in contrast of peak shift of Miller capacitor Cgd for n-type TFETs with donor-like and acceptor-like ITs.