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In traditional service-oriented architecture(SOA),web service providers register their service descriptions in the registry for service consumers to discover and invoke services.Traditional SOA lacks dispute resolution mechanism,so that the trusted service invocation between service consumers and providers can not be guaranteed.Blockchain can be reasonably introduced into the dispute resolution mechanism due to its significant advantages in decentralization and tamper resistance.Therefore,this paper proposes a trusted SOA architecture based on blockchain,in which blockchain acts as evidence recorder and service registry agent. During a service trusted invocation,the service consumer first encrypts the parameters and sends them to the target service provider.Secondly,the service provider receives the encryption parameters and decrypts them.Then,the service provider completes the service execution and encrypts the output result.Finally,when the service provider sends the encryption result to the service consumer,it completes the trusted credential construction and uplink.Based on the above,when a service dispute occurs,it will trigger the adjudication of the smart contract.The execution of the contract relies on trusted vouchers to correctly handle service disputes.Experimental results show that,compared with the traditional invocation,the proposed method can correctly handle the service disputes between service providers and requesters on the premise of ensuring that the growth rate of trusted invocation time of most services is no more than 30%.

In this study, we demonstrate breakdown voltage at 1500 V of GaN on a QST power device. The high breakdown voltage and low current collapse performance can be attributed to the higher quality of GaN buffer layers grown on QST substrates. This is primarily due to the matched coefficient of thermal expansion (CTE) with GaN and the enhanced mechanical strength. Based on computer-aided design (TCAD) simulations, the strong electric-field-induced trap-assisted thermionic field emissions (TA-TFEs) in the GaN on QST could be eliminated in the GaN buffer. This demonstration showed the potential of GaN on QST, and promises well-controlled performance and reliability under high-power operation conditions. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine whether the efficiency, precision, and validity of computerized adaptive testing (CAT) could be improved by assessing confidence differences in knowledge that examinees possessed. We proposed a novel polytomous CAT model called the confidence-weighting computerized adaptive testing (CWCAT), which combined a confidence-weighting scoring scheme with the graded response model (GRM). The CWCAT provided a more interactive testing environment by focusing on the examinees' confidence in their responses. An experiment was conducted to evaluate the comparison between the CWCAT and conventional CAT in terms of efficiency, precision, and validity. As expected, the polytomous method provided better discrimination among individual differences in the confidence in knowledge and required fewer items per examinee. Results also showed that CWCAT yielded ability estimates that were higher and better correlated to examinees' performance in English learning. Furthermore, the ability measured by CWCAT was not as likely to be affected by guessing as on conventional CAT, and, therefore, was more consistent with examinees' true ability. (Contains 9 tables and 9 figures.)

Abstract Background Fibronectin (FN) is known to be a large multifunction glycoprotein with binding sites for many substances, including N-terminal and C-terminal heparin-binding domains. We investigated the effects of highly purified rhFNHN29 and rhFNHC36 polypeptides originally cloned from the two heparin-binding domains on the adhesion and invasion of highly metastatic human hepatocellular carcinoma cells (MHCC97H) and analyzed the underlying mechanism involved. Methods The MHCC97H cells that adhered to FN in the presence of various concentrations of rhFNHN29 and rhFNHC36 polypeptides were stained with crystal violet and measured, and the effects of rhFNHN29 and rhFNHC36 on the invasion of the MHCC97H cells were then detected using the Matrigel invasion assay as well as a lung-metastasis mouse model. The expression level of integrins and focal adhesion kinase (FAK) phosphotyrosyl protein was examined by Western blot, and the activity of matrix metalloproteinases (MMPs) and activator protein 1 (AP-1) was analyzed by gelatin zymography and the electrophoretic mobility band-shift assay (EMSA), respectively. Results Both of the polypeptides rhFNHN29 and rhFNHC36 inhibited adhesion and invasion of MHCC97H cells; however, rhFNHC36 exhibited inhibition at a lower dose than rhFNHN29. These inhibitory effects were mediated by integrin αvβ3 and reversed by a protein tyrosine phosphatase inhibitor. Polypeptides rhFNHN29 and rhFNHC36 abrogated the tyrosine phosphorylation of focal adhesion kinase (p-FAK) and activation of activator protein 1 (AP-1), resulting in the decrease of integrin αv, β3 and β1 expression as well as the reduction of MMP-9 activity. Conclusions Polypeptides rhFNHN29 and rhFNHC36 could potentially be applicable to human liver cancer as anti-adhesive and anti-invasive agents.

Abstract: Two series of raw materials were adopted to form TiAl/Ti2AlC composites: Ti/Al/TiC and Ti/Al/C. Differential thermal analysis (DTA) of starting powers and X-ray diffraction (XRD) of samples sintered at different temperatures from 600°C to 1300°C by hot pressing were utilized to analyze the phase transformation and the mechanism of synthesis. Scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS) was utilized to investigate the morphology characteristics of the products. The experimental results showed that Ti reacted with Al to form TiAl intermetallics below 900°C; and above 900°C, TiAl reacted with TiC to produce dense TiAl/Ti2AlC composites. The products sintered at 1200°C had fine crystals and dense fibres, and the distribution of Ti2AlC particles in TiAl matrix was homogeneous. [Copyright &y& Elsevier]

Abstract: Adsorption of ammonia (NH3) onto activated carbons prepared from palm shells impregnated with sulfuric acid (H2SO4) was investigated. The effects of activation temperature and acid concentration on pore surface area development were studied. The relatively large micropore surface areas of the palm-shell activated carbons prepared by H2SO4 activation suggest their potential applications in gas adsorption. Adsorption experiments at a fixed temperature showed that the amounts of NH3 adsorbed onto the chemically activated carbons, unlike those prepared by CO2 thermal activation, were not solely dependent on the specific pore surface areas of the adsorbents. Further adsorption tests for a wide range of temperatures suggested combined physisorption and chemisorption of NH3. Desorption tests at the same temperature as adsorption and at an elevated temperature were carried out to confirm the occurrence of chemisorption due to the interaction between NH3 and some oxygen functional groups via hydrogen bonding. The surface functional groups on the adsorbent surface were detected by Fourier transform infrared spectroscopy. The amounts of NH3 adsorbed by chemisorption were correlated with the contents of elemental oxygen present in the adsorbents. Mechanisms for chemical activation and adsorption processes are proposed based on the observed phenomena. [Copyright &y& Elsevier]

Background: Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) represent the predominant histological types of primary liver cancer, comprising over 99% of cases. Given their differing biological behaviors, prognoses, and treatment strategies, accurately differentiating between HCC and ICC is crucial for effective clinical management. Radiomics, an emerging image processing technology, can automatically extract various quantitative image features that may elude the human eye. Reports on the application of ultrasound (US)-based radiomics methods in distinguishing HCC from ICC are limited., Aim: To develop and validate an ultrasomics model to accurately differentiate between HCC and ICC., Methods: In our retrospective study, we included a total of 280 patients who were diagnosed with ICC ( n = 140) and HCC ( n = 140) between 1999 and 2019. These patients were divided into training ( n = 224) and testing ( n = 56) groups for analysis. US images and relevant clinical characteristics were collected. We utilized the XGBoost method to extract and select radiomics features and further employed a random forest algorithm to establish ultrasomics models. We compared the diagnostic performances of these ultrasomics models with that of radiologists., Results: Four distinct ultrasomics models were constructed, with the number of selected features varying between models: 13 features for the US model; 15 for the contrast-enhanced ultrasound (CEUS) model; 13 for the combined US + CEUS model; and 21 for the US + CEUS + clinical data model. The US + CEUS + clinical data model yielded the highest area under the receiver operating characteristic curve (AUC) among all models, achieving an AUC of 0.973 in the validation cohort and 0.971 in the test cohort. This performance exceeded even the most experienced radiologist (AUC = 0.964). The AUC for the US + CEUS model (training cohort AUC = 0.964, test cohort AUC = 0.955) was significantly higher than that of the US model alone (training cohort AUC = 0.822, test cohort AUC = 0.816). This finding underscored the significant benefit of incorporating CEUS information in accurately distinguishing ICC from HCC., Conclusion: We developed a radiomics diagnostic model based on CEUS images capable of quickly distinguishing HCC from ICC, which outperformed experienced radiologists., Competing Interests: Conflict-of-interest statement: We have no financial relationships to disclose., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.)

Recent studies have shown that induced expression of endogenous antioxidative enzymes thr-ough activation of the antioxidant response element/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway may be a neuroprotective strategy. In this study, rat cerebral cortical neurons cultured in vitro were pretreated with 10 μM curcumin or post-treated with 5 μM curcumin, respectively before or after being subjected to oxygen-glucose deprivation and reoxygenation for 24 hours. Both pretreatment and post-treatment resulted in a significant decrease of cell injury as indicated by propidium iodide/Hoechst 33258 staining, a prominent increase of Nrf2 protein expression as indicated by western blot analysis, and a remarkable increase of protein expression and enzyme activity in whole cell lysates of thioredoxin before ischemia, after ischemia, and after reoxygenation. In addition, post-treatment with curcumin inhibited early DNA/RNA oxidation as indicated by immunocytochemistry and increased nuclear Nrf2 protein by inducing nuclear accumulation of Nrf2. These findings suggest that curcumin activates the expression of thioredoxin, an antioxidant protein in the Nrf2 pathway, and protects neurons from death caused by oxygen-glucose deprivation in an in vitro model of ischemia/reperfusion. We speculate that pharmacologic stimulation of antioxidant gene expression may be a promising approach to neuroprotection after cerebral ischemia.