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To investigate the value of R2* mapping-based radiomics nomograms in staging liver fibrosis in patients with chronic hepatitis B.Between January 2020 and December 2020, 151 patients with chronic hepatitis B were randomly divided into training (n = 103) and validation (n = 48) cohorts. From January to February 2021, 58 patients were included in a test cohort. Radiomics features were selected using the interclass correlation coefficient and least absolute shrinkage and selection operator method. Three radiomics nomograms, combining the radiomics score (Radscore) derived from R2* mapping and clinical variables, were used for staging significant and advanced fibrosis, and cirrhosis. Performance of the model was evaluated using the AUC. The utility and clinical benefits were evaluated using the continuous net reclassification index (NRI), integrated discrimination improvement (IDI), and decision curve analysis (DCA).The Radscore calculated by 12 radiomics features and independent factors (laminin and platelet) of advanced fibrosis were used to construct the radiomics nomograms. In the test cohort, the AUCs of the radiomics nomograms for staging significant fibrosis, advanced fibrosis, and cirrhosis were 0.738 (95% confidence interval [CI]: 0.604-0.872), 0.879 (95% CI: 0.779-0.98), and 0.952 (95% CI: 0.878-1), respectively. NRI, IDI, and DCA confirmed that radiomics nomograms demonstrated varying degrees of clinical benefit and improvement for advanced fibrosis and cirrhosis, but not for significant fibrosis.Radiomics nomograms combined with R2* mapping-based Radscore, laminin, and platelet have value in staging advanced fibrosis and cirrhosis but limited value for staging significant fibrosis.• Laminin and platelets were independent predictors of advanced fibrosis. • Radiomics analysis based on R2* mapping was beneficial for evaluating advanced fibrosis and cirrhosis. • It was difficult to distinguish significant fibrosis using a radiomics nomogram, which is possibly due to the complex pathological microenvironment of chronic liver diseases.

A reactive-type flame retardant, polyvinylphenylsilsesquioxane (PVP), was synthesized and incorporated into thiol-ene (TE) to prepare a flame-retardant TE (FRTE) composite. The thermal stability an...

The thiol-ene (TE) polymerization systems have gained a lot of interests from industry and researchers in the last years. A phosphorus-silicon containing flame retardant DOPO-V was synthesized in this study, and the effect of DOPO-V on the flame retardancy of thiol ene was confirmed by cone calorimetry measurement. Moreover, the thermal stability of TE/DOPO-V (FRTE) composite was investigated by the thermogravimetric method under dynamic conditions (50–600°C) in nitrogen atmosphere. Moreover, kinetic parameters were calculated by the Kissinger and Flynn-Wall-Ozawa methods. It was observed that the activation energy for the FRTE degradation was slightly higher than that of pure TE. This was attributed to the fact that DOPO-V could further react with the TE matrix to form a complex and stable phosphorus-silicon containing char layer. Thus, the flame retardancy of FRTE/DOPO-V was higher than that of pure TE. By using both methods approximately equal values of activation energy were obtained.

Polyaminopropylphenylsilsesquioxane (PA) was proved to be an effective fire retardant for epoxy resin (EP) by cone calorimeter measurements, since a significant peak heat release rate (PHRR) reduct...

Functionalized graphene nanosheets (GO-PA) were synthesized by a facile covalent grafting of graphene oxide (GO) with polyaminosilicone (PA). The structure and morphology of GO-PA were characterize...

In this article, a novel phosphorus and silicon-containing flame retardant (DOPO-V-PA) was synthesized via condensation reaction and then added into thiol-ene (TE) to prepare a flame-retardant composite. The results of cone calorimeter measurement demonstrated that, compared with pure TE, 22.7% and 53.2% reduction of TE/DOPO-V-PA (thiol-ene/9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide-vinyltrimethoxysilane-phenyltrimethoxysilane-(3-aminopropyl)trimethoxysilane copolymer) was found for the peak heat release rate (PHRR) and total heat release (THR), respectively. The thermal degradation of TE composites was investigated by the TGA measurement under non-isothermal conditions, and kinetic parameters were both calculated by the Kissinger and Flynn-Wall-Ozawa methods. It was indicated that the activation energies of TE at conversions exceeding 50% were enhanced by the incorporation of DOPO-V-PA for the whole conversion range.

Via the surface-grafting of carbon nanotubes (CNTs) with a silicon-containing flame retardant (PMDA), a novel flame retardant CNTs-PMDA was synthesized. The flame retardancy was tested by cone calorimeter. Compared with pure epoxy resin, the total heat release (THR) and peak heat release rate (PHRR) of epoxy resin containing CNTs-PMDA were significantly reduced, by 44.6% and 24.6%, respectively. Furthermore, thermal degradation behavior of epoxy resin based composite was studied by the thermogravimetric analysis with differences in heating rates. The kinetic parameters of the thermal degradation for epoxy resin composites were evaluated by the Kissinger method and Flynn-Wall-Ozawa method. The results suggested that activation energy values of epoxy resin containing CNTs-PMDA in thermal degradation process were higher than those of pure epoxy resin in the final stage of the thermal degradation process, which was closely related to the final formation of char layer residues. Finally, the results from Dynamic mechanical thermal analysis (DMTA) and Scanning electron microscopy (SEM) measurements exhibited that the functionalization of CNTs with PMDA obviously improved the dispersion of CNTs in the epoxy resin matrix.

Allelopathy is an important process in plant communities, but the role of seed allelopathy in natural ecosystems remains poorly understood. In the present study, we examined the potential allelopathic effects of Ligularia virgaurea (a dominant species in degraded Tibetan grasslands) seeds on the germination of four native grass species (Festuca sinensis, Agrostis gigantean, Bromus inermis, and Elymus nutans). The results showed that L. virgaurea seeds can have potential allelopathic effects on seed germination, mean time to germination and root growth rates of native grass species. We further demonstrate that these effects are driven by a water-soluble seed leachate. Species with smaller seeds were generally more sensitive than larger seeded species. The results suggest that seed-to-seed allelopathic potential may be an important mechanism driving the dominance of L. virgaurea in degraded alpine grasslands on the Tibetan Plateau. Further studies are required to demonstrate effects of seed-to-seed potential allelopathy in a field setting.

The property market in Hong Kong plays an important role in the political, social and economic life of this vibrant city. Understanding the dynamics of the market is essential to guide government policy making and investment decisions. Using data collected between 1993 and 2006, this study investigates the monthly returns, volatilities, and time-varying correlations in the residential, office, and retail property markets in Hong Kong. A vector autoregressive (VAR) model is used to examine the conditional mean, and a multivariate generalized autoregressive conditional heteroscedasticity (MGARCH) model is adopted to analyze the conditional variance. The dynamic conditional correlation (DCC) approach is utilized to specify the MGARCH model. All of the property types show strong auto- and cross-correlations, which indicates that the sectors relate to each other closely. All three sectors have higher volatilities when major political and economic events occur. The findings reveal the possibility of balancing investment portfolios between the three sectors in the Hong Kong property market. However, exposure to the residential sector may reduce the chance of investment diversification because of the higher correlation of this sector with the other property sectors.

Variations in hormone levels during different phases of the menstrual cycle have been shown to alter the pharmacokinetics of some medications and are known to exert significant effects on seemingly unrelated physiologic parameters. Numerous studies have been undertaken to examine the effects of different phases of the menstrual cycle on leukocyte and differential counts, but results have often been inconclusive and contradictory. This study endeavored to reexamine these parameters, measured by standard laboratory assays, in healthy ovulating females to determine whether the menstrual cycle may have clinically relevant effects on leukocyte counts. Twenty-one women, aged 18 to 35 years and not taking hormonal contraception, were enrolled in an outpatient study within 12 hours after the onset of normal menses. The women reported to the clinical pharmacology unit for a complete blood count with differential on days 1, 2, 7, 10 through 17, 22, and 25 through 32. Blinded duplicate samples were obtained on day 2 to assess variability at the analytic site, and levels of luteinizing hormone and estradiol were measured on days 11 through 16 to determine the day of ovulation. Eighteen women completed the study, with cycle lengths ranging from 24 to 31 days (28.2 +/- 1.9 days, mean +/- SD). Evaluations of the data revealed a trend toward higher leukocyte counts and absolute neutrophil counts at the onset of menses but no significant or clinically relevant effects of different phases of the menstrual cycle on these parameters. Some split samples showed considerable variation in the assays (eg, a 42% increase in absolute neutrophil counts), suggesting that errors at the analytic facility may be a more important consideration than hormonal effects.

A technique for morphology control of self-assembled organic films based on laser ablation is presented. The regioregular poly 3-hexylthiophene (RR-P3HT) films prepared by using drop casting method and spin coating method are irradiated and ablated by the ultraviolet KrF excimer laser. Absorption spectra and XRD profiles of the films are investigated. For spin coated films, Blue absorption spectral shift is observed; For drop cast films, Blue shift in the absorption spectra, accompanied with the disappearance of the peak intensity of XRD profiles, are observed. The results indicate that molecular structure has been changed due to photo-thermal effect and molecule cutting effect of laser ablation.

Network Intrusion Detection System is a significant guarantee means for network security. However, the current Network Intrusion Detection System generally suffers from less prior knowledge which then leads to poor generalizing ability. Network Intrusion Detection System based on Support Vector Machine is endowed with favorable generalizing ability even with small sample size (less prior knowledge). The paper first gives an introduction to the basic concept of intrusion detection and the basic principle of the classifier based on Support Vector Machine, then discusses algorithm of Support Vector Machine, and finally forms Network Intrusion Detection System combining Anomaly Intrusion Detection and Misuse Intrusion Detection, based on Support Vector Machine.

s— This paper presents the reasons for the error of resistive voltage transformer based on a mathematical model which consider the influence of the temperature and the distributed capacitance. In this paper, a resistive voltage divider is designed as the sensor of resistive voltage transformer. And the paper analyzes the performance of the sensor in error experiment and temperature experiment. The results present that the distributed capacitance made a big phase error, but through blocking the external influence it would be stable and can be compensated by electronic units. The study concludes that matching the temperature coefficient is an efficient way to reduce the temperature influence. I. INTRODUCTION In recent decades, with the application of microcomputer in the power system, intelligence and automation of the power system have been constantly improved. The modern distribution system, monitoring system and protective system are based on measuring elements, so new requirements emerge in relation to the power instrument transformer. Most of traditional voltage transformers are electromagnetic voltage transformers and capacitor voltage transformers, both kinds of which possess electromagnetic units. Measuring range of the electromagnetic voltage transformer suffers from restriction of

Phasor measurement unit (PMU) is the basic unit in wide area protection (WAP) in power system. At present, development of PMU based on American GPS (Global Positioning System) is very common. However, because GPS is developed and held by American independently and some other reasons, PMU based on GPS exists unavoidable potential security hazard. Therefore, research and development of PMU based on satellite navigation system developed by our own country is both inevitable and necessary. This paper analyzes the importance and feasibility of PMU based on "Beidou I" satellite navigation system, which is developed by China and has been put into civil use. "Beidou I" satellite navigation system's service area satisfies the interconnection requirement throughout the whole country's power grids. The one way time transmission accuracy is up to 100 ns, which can already meets the PMU requirement for synchronous signals. The price performance ratio is relatively higher than PMU based on GPS. Therefore the paper introduces a PMU design scheme based on "Beidou I" satellite navigation system. The technology shall be of great use for the future development of China's wide area protection system.

Measurements of nitric oxide (NO) release at single cell level are fundamental to understand the diverse physiological functions of this remarkable molecule. To achieve this purpose, capillary electrophoresis with laser-induced fluorescence detection (CE-LIF) was originally described for the sensitive determination of NO release in individual neuron and mammalian cell after 8-(3,4-diaminophenyl)-2,6-bis(2-carboxyethyl)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (DAMBO-P(H)) was chosen as the fluorescent probe. Various parameters affecting NO trapping in vivo and CE separation were systematically studied. Under the optimal conditions, complete and fast separation of the resulted targeted high-fluorescent triazole (DAMBO-P(H)-T) was achieved in about 3 min (2.89 min), and the relative standard deviations (RSDs) values of migration time and peak area were less than 5% and 9% for intra-day and inter-day assays, respectively. The detection limit was 42 amol (at a signal-to-noise ratio of 3). The feasibility of application of the developed method was validated by successfully applied to the measurements of NO release from four single cell study models. This original application of this method in diverse samples represents a powerful tool to study the kinetics of NO release by neuronal cells during neurotransmission, as well as for the understanding of the pathobiological and therapeutic basis of this molecule for cardiovascular diseases and under oxidative stress.