Recently, organic metal halide perovskites have emerged as one of the most promising photoactive materials in the field of photovoltaics. Over the past six years, the efficiency of perovskite solar ...cells (PSCs) has increased from initially 3.8% to 20.8% through the optimization of perovskite film fabrication and device architecture. However, perovskites suffer inherent instability and degrade rapidly under different exposures (water, oxygen, UV-light irradiation and high temperature), limiting their further application to commercialization. Herein, several studies have been carried out to resolve this problem to some extent. In this paper, possible degradation mechanisms are summarized in order to help us understand the process of perovskite decomposition. Moreover, we also systematically outline and classify the approaches to improve the long-term stability of perovskite devices.
Recently, organic metal halide perovskites have emerged as one of the most promising photoactive materials in the field of photovoltaics.
In recent years, many studies have found that mechanical tension can activiate NF-kB signal pathway and NF-kB plays an important role in the process of osteogenesis. However, it is still unclear ...whether this process exists in the anterior palatal suture expansion. In this paper, we mainly studied the effect of intraperitoneal injection of PDTC on the NF-kB signaling pathway and osteogenesis index of the anterior palatal suture expansion model in young adult rats. The expansion model is grouped and established: 45 male 8-week-old Sprague-Dawley rats were randomly divided into three groups, an expansion only (EO) group, an expansion plus PDTC (PE) group, and a control group. The results revealed that PDTC inhibited the activity of NF-kB signaling pathway and promote one morphogenetic protein 2 (BMP-2), steocalatin (OCN) expression. Compared with the control group, the optical density (OD) value of BMP in the EO group and PE group rats increased significantly from the first day to the seventh day, and the difference was statistically significant (P<0.05). After 6.0Gy irradiation, PDTC administration group could slightly increase the total SOD level in the liver and serum of rats, and reduce the MDA level in the liver and serum, especially the effect of 60mg/kg and 90mg/kg was the most obvious.
Many clinical studies have been carried out to investigate the relationship between periodontitis and rheumatoid arthritis (RA). Owing to limited evidence and inconsistent findings among these ...studies, it is unclear whether periodontitis would increase the risk for RA. This meta-analysis was performed to evaluate whether periodontitis represents a risk factor for RA.
PubMed, Cochrane Library, Embase, Web of Science, and Wanfang were searched for eligible studies that compared periodontitis patients with controls. A pooled odds ratio (OR) and 95% confidence interval (CI) were calculated to assess the association between periodontitis and RA.
Thirteen studies including a total of 706611 periodontitis patients and 349983 control subjects were included. The pooled OR of RA risk between periodontitis and controls was (OR: 1.69; 95% CI: 1.31–2.17; P<0.0001), indicating that the patients in periodontitis group had a 69% greater risk for RA than people in control group. When stratified by disease type, the pooled results showed periodontitis represents a risk factor for incident RA (OR=1.70, 95%CI: 0.75–3.85, P<0.001) and mixed RA (OR=1.61, 95%CI: 1.26–2.06; P<0.001). When stratified by disease duration, the pooled results showed periodontitis represents a risk factor for RA disease duration>5 years (OR=2.88, 95%CI: 0.66–12.62, P=0.018), disease duration<5 years (OR=2.59, 95%CI: 0.83–8.11, P<0.001), mixed disease duration (OR=1.53; 95%CI: 1.05–2.22, P<0.001).
Our meta-analysis revealed an increased risk of RA in patients with periodontitis compared to healthy controls. Moreover, when stratified by disease type, there was a higher risk between incident RA and periodontitis. When stratified by disease duration, the patients with periodontitis might be more closely associated with the RA patients with disease duration >5 years.
Community detection involves grouping the nodes of a network such that nodes in the same community are more densely connected to each other than to the rest of the network. Previous studies have ...focused mainly on identifying communities in networks using node connectivity. However, each node in a network may be associated with many attributes. Identifying communities in networks combining node attributes has become increasingly popular in recent years. Most existing methods operate on networks with attributes of binary, categorical, or numerical type only. In this study, we introduce kNN-enhance, a simple and flexible community detection approach that uses node attribute enhancement. This approach adds the k Nearest Neighbor (kNN) graph of node attributes to alleviate the sparsity and the noise effect of an original network, thereby strengthening the community structure in the network. We use two testing algorithms, kNN-nearest and kNN-Kmeans, to partition the newly generated, attribute-enhanced graph. Our analyses of synthetic and real world networks have shown that the proposed algorithms achieve better performance compared to existing state-of-the-art algorithms. Further, the algorithms are able to deal with networks containing different combinations of binary, categorical, or numerical attributes and could be easily extended to the analysis of massive networks.
Data integrity is a prerequisite for ensuring data availability of IoT data and has received extensive attention in the field of IoT big data security. Stream computing systems are widely used in the ...field of IoT for real-time data acquisition and computing. However, the real-time, volatility, suddenness, and disorder of stream data make data integrity verification difficult. According to the survey, there is no mature and universal solution. To solve this issue, we constructed a data integrity verification algorithm scheme of the stream computing system (S-DIV) by utilizing homomorphic message authentication code and pseudo-random function security assumption. Furthermore, based on S-DIV, an external data integrity tracking and verification system is constructed to track and analyze the message data stream in real time. By verifying the data integrity of message during the whole life cycle, the problem of data corruption or data loss can be found in time, and error alarm and message recovery can be actively implemented. Then, we conduct the formal security analysis under the standard model and, finally, implement the S-DIV scheme in simulation environment. Experimental results show that the scheme can guarantee data integrity in an acceptable time without affecting the efficiency of the original system.
Tetrandrine, a bisbenzylisoquinoline alkaloid that was isolated from the medicinal plant Stephania tetrandrine S. Moore, was recently identified as a novel chemotherapy drug. Tetrandrine exhibited a ...potential antitumor effect on multiple types of cancer. Notably, an enhanced therapeutic efficacy was identified when tetrandrine was combined with a molecularly targeted agent. H89 is a potent inhibitor of protein kinase A and is an isoquinoline sulfonamide.
The effects of H89 combined with tetrandrine were investigated in vitro with respect to cell viability, apoptosis and autophagy, and synergy was assessed by calculation of the combination index. The mechanism was examined by western blot, flow cytometry and fluorescence microscopy. This combination was also evaluated in a mouse xenograft model; tumor growth and tumor lysates were analyzed, and a TUNEL assay was performed.
Combined treatment with H89 and tetrandrine exerts a mostly synergistic anti-tumor effect on human cancer cells in vitro and in vivo while sparing normal cells. Mechanistically, the combined therapy significantly induced cancer cell apoptosis and autophagy, which were mediated by ROS regulated PKA and ERK signaling. Moreover, Mcl-1 and c-Myc were shown to play a critical role in H89/tetrandrine combined treatment. Mcl-1 ectopic expression significantly diminished H89/tetrandrine sensitivity and amplified c-Myc sensitized cancer cells in the combined treatment.
Our findings demonstrate that the combination of tetrandrine and H89 exhibits an enhanced therapeutic effect and may become a promising therapeutic strategy for cancer patients. They also indicate a significant clinical application of tetrandrine in the treatment of human cancer. Moreover, the combination of H89/tetrandrine provides new selectively targeted therapeutic strategies for patients with c-Myc amplification.
A facile method for preparing an easy processing, repeatable and flexible pressure sensor was presented via the synthesis of modified multi-walled carbon nanotubes (m-MWNTs) and polyurethane (PU) ...films. The surface modification of multi-walled carbon nanotubes (MWNTs) simultaneously used a silane coupling agent (KH550) and sodium dodecyl benzene sulfonate (SDBS) to improve the dispersibility and compatibility of the MWNTs in a polymer matrix. The electrical property and piezoresistive behavior of the m-MWNT/PU composites were compared with raw multi-walled carbon nanotube (raw MWNT)/PU composites. Under linear uniaxial pressure, the m-MWNT/PU composite exhibited 4.282%kPa
sensitivity within the pressure of 1 kPa. The nonlinear error, hysteresis error and repeatability error of the piezoresistivity of m-MWNT/PU decreased 9%, 16.72% and 54.95% relative to raw MWNT/PU respectively. Therefore, the piezoresistive response of m-MWNT/PU had better stability than that of raw MWNT/PU composites. The m-MWNT/PU sensors could be utilized in wearable devices for body movement detection, monitoring of respiration and pressure detection in garments.
The online healthcare community (OHC) has attained rapid development in recent years in which users are facilitated to exchange disease information and seek medical treatment. However, users' ...motivation of participation in OHCs is still under investigation. Taking the perspective of user perceived value, this paper examined the impacts of different incentive levels including identity incentive, privilege incentive, and material incentive on user perceived value, user engagement, and user loyalty. To test the proposed hypotheses, the study adopted the methods of the between-subjects experiment and questionnaire. Based on the data analysis by ANOVA and structural equation model, the results show there are significant differences in the impacts of different incentive levels on users' perceived value. Most of the incentive measures exert significant effects on simple user hedonic value and community identity value. Accordingly, the research findings suggest that affective support value and self-health management value demonstrate more importance for user engagement and user loyalty. Therefore, OHCs should try to improve users' affective support value and self-health management value which are the ultimate aims of the OHCs. Our study sheds some light on profoundly understanding the design of incentive mechanism of OHC and contributes to the research of OHC services.
Large intergenic noncoding RNA regulator of reprogramming (Linc‐RoR) was first identified as a regulator to increase the emergence of induced pluripotent stem cells through reprogramming ...differentiated cells and is abnormal expression in a variety of malignant tumors. However, the function of Linc‐RoR in pancreatic cancer progression needs further clarification. The data from this study demonstrated that Linc‐RoR knockdown suppressed cell proliferative capacity and colony formation, while Linc‐RoR overexpression promoted these behaviors. In particular, Linc‐RoR overexpression promoted the level of mesenchymal markers, inhibited the expression of epithelial markers, as well as enhanced pancreatic cancer cells migration and invasion, whereas Linc‐RoR knockdown inhibited the expression of mesenchymal markers, promoted the expression of epithelial markers, as well as weakened pancreatic cancer cells migration and invasion. Further study revealed that Linc‐RoR knockdown brought about a significant fall in YAP phosphorylation and a rise in total YAP, while Linc‐RoR overexpression produced the opposite results. Specifically, Linc‐RoR promoted YAP in the cytoplasm into the nucleus. Taken together, we conjectured that Linc‐RoR promoted proliferation, migration, and invasion of pancreatic cancer cells by activating the Hippo/YAP pathway. YAP might be an underlying target of Linc‐RoR and mediate epithelial‐mesenchymal transition (EMT) in pancreatic cancer (PC); thus, Linc‐RoR might be a very meaningful biomarker for PC.
Large intergenic noncoding RNA regulator of reprogramming (Linc‐RoR) promoted proliferation, migration, and invasion of pancreatic cancer cells by activating the Hippo/YAP pathway. YAP might be an underlying target of Linc‐RoR and mediate EMT in pancreatic cancer (PC); thus, Linc‐RoR might be a very meaningful biomarker for PC
The giant magnetostrictive transducer (GMT) can be widely used in ultra-precision machining in precision-fluid-control fields. The temperature stability of GMT is critical for the reliable generation ...of output characteristics. This study presents a magnetic-energy-losses method for the GMT working at high frequency, and designs a temperature-stable control system to improve energy transmission and heat dissipation. Based on the loss-separation theory and experimental data, the temperature-rise characteristics of the transducer are analyzed. The temperature rise considers the effects of hysteresis loss, the eddy-current loss, the anomalous loss and the Joule heat. A constitutive relation among losses, frequency and magnetic-flux density is given. The temperature distribution of the transducer can be quickly and accurately calculated, using the constitutive equation. According to the convective heat-transfer and the thermal-compensation method, a temperature-control system is designed. A prototype of the system is then fabricated and tested to verify the feasibility and efficacy of the proposed design methods. The results demonstrate that the output- displacement deviation can be controlled at less than 0.65 μm, and the temperature difference is less than 3 °C.
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