26 research outputs found

    Estimating moisture susceptibility of asphalt modified with alumina trihydrate

    Get PDF
    U radu je na temelju slobodne površinske energije, ocijenjena osjetljivost asfalta s aluminijevim trihidratom na vlagu. Analizirana su fizikalna svojstva i zapaljivost uzoraka s dodatkom aluminijeva trihidrata. Za potrebe istraživanja izrađeni su uzorci asfalta modificiranog stiren-butadien-stirenom s različitim udjelima ATH-a (0-14 %). Na uzorcima s dodatkom ATH-a analizirano je povećanje viskoznosti, točka razmekšanja, otpornost bitumena prema kolotraženju, granični indeks kisika i indeks penetracije. Iz aspekta mikromehanizama, ATH u velikoj mjeri nepovoljno utječe na oštećenje asfaltne mješavine uslijed djelovanja vlage.The moisture susceptibility of asphalt containing alumina trihydrate (ATH) was assessed through the surface free energy. Physical properties and flame retardancy of ATH samples were also investigated. For research purposes SBS modified asphalt samples with different dosages (0-14 %) of ATH were prepared. Increased viscosity, softening point limiting oxygen index and lower penetration ductility, were investigated for the ATH modified samples. ATH has a significant negative effect on the moisture-induced damage potential of asphalt mixture from the view of micromechanisms

    Versatile Dibenzothio[seleno]phenes via Hexadehydro-Diels–Alder Domino Cyclization

    Get PDF
    A facile strategy to synthesize highly substituted dibenzoselenophenes and dibenzothiophenes by a domino hexadehydro-Diels–Alder reaction is reported in this article. The formation of three new C–C bonds, one new Caryl–Se/Caryl–S bond, and C–H σ-bond migration via one-pot multiterminal cycloaddition reactions were involved in over three transformations. The target tetracyclic compounds were prepared from tetraynes with a triphenylphosphine selenide or triphenylphosphine sulfide. This reaction played a pivotal role in constructing natural thio[seleno]phene cores, which were highly substituted, and is a robust method for producing fused heterocycles

    Building nonenhanced CT based radiomics model in discriminating arteriovenous malformation related hematomas from hypertensive intracerebral hematomas

    Get PDF
    ObjectiveTo develop and validate radiomics models on non-enhanced CT for discrimination of arteriovenous malformation (AVM) related hematomas from hypertensive intracerebral hematomas.Materials and methodsA total of 571 patients with acute intraparenchymal hematomas and baseline non-enhanced CT scans were retrospectively analyzed, including 297 cases of AVM related hematomas and 274 cases of hypertensive intracerebral hematomas. The patients were divided into training and validation cohorts in a 7:3 ratio with a random seed. A total of 1,688 radiomics features of hematomas were extracted from non-enhanced CT. Then, the least absolute shrinkage and selection operator (LASSO) regression was applied to select features and construct the radiomics models. In this study, a radiomics-based model was constructed that based on the radiomics features only. Furthermore, a combined model was constructed using radiomics features, clinical characteristics and radiological signs by radiologists’ evaluation. In addition, we compared predictive performance of the two models for discrimination of AVM related hematomas from hypertensive intracerebral hematomas.ResultsA total of 67 radiomics features were selected to establish radiomics signature via LASSO regression. The radiomics-based model was constructed with 2 classifiers, support vector machine (SVM) and logistic regression (LR). AUCs of the radiomics-based model in the training set were 0.894 and 0.904, in validation set were 0.774 and 0.782 in SVM classifier and LR classifier, respectively. AUCs of the combined model (combined with radiomics, age and calcification) in the training set were 0.976 and 0.981, in validation set were 0.896 and 0.907 in SVM classifier and LR classifier, respectively. The combined model showed greater AUCs than radiomics-based model in both training set and validation set.ConclusionThe combined model using radiomics, age and calcification showed a satisfactory predictive performance for discrimination of AVM related hematomas from hypertensive intracerebral hematomas and hold great potential for personalized clinical decision

    Rapidly progressive interstitial lung disease risk prediction in anti-MDA5 positive dermatomyositis: the CROSS model

    Get PDF
    BackgroundThe prognosis of anti-melanoma differentiation-associated gene 5 positive dermatomyositis (anti-MDA5+DM) is poor and heterogeneous. Rapidly progressive interstitial lung disease (RP-ILD) is these patients’ leading cause of death. We sought to develop prediction models for RP-ILD risk in anti-MDA5+DM patients.MethodsPatients with anti-MDA5+DM were enrolled in two cohorts: 170 patients from the southern region of Jiangsu province (discovery cohort) and 85 patients from the northern region of Jiangsu province (validation cohort). Cox proportional hazards models were used to identify risk factors of RP-ILD. RP-ILD risk prediction models were developed and validated by testing every independent prognostic risk factor derived from the Cox model.ResultsThere are no significant differences in baseline clinical parameters and prognosis between discovery and validation cohorts. Among all 255 anti-MDA5+DM patients, with a median follow-up of 12 months, the incidence of RP-ILD was 36.86%. Using the discovery cohort, four variables were included in the final risk prediction model for RP-ILD: C-reactive protein (CRP) levels, anti-Ro52 antibody positivity, short disease duration, and male sex. A point scoring system was used to classify anti-MDA5+DM patients into moderate, high, and very high risk of RP-ILD. After one-year follow-up, the incidence of RP-ILD in the very high risk group was 71.3% and 85.71%, significantly higher than those in the high-risk group (35.19%, 41.69%) and moderate-risk group (9.54%, 6.67%) in both cohorts.ConclusionsThe CROSS model is an easy-to-use prediction classification system for RP-ILD risk in anti-MDA5+DM patients. It has great application prospect in disease management

    Investigating the Effect of Aggregate Characteristics on the Macroscopic and Microscopic Fracture Mechanisms of Asphalt Concrete at Low-Temperature

    No full text
    The low-temperature crack of asphalt concrete is considered to be one of the main deteriorations in asphalt pavements. However, there have been few studies on the composite effects of the aggregate characteristics and fracturing modes on the low-temperature cracking of asphalt concrete. Hence, the edge cracked semi-circular bend tests and the discrete element modeling approaches are combined to investigate the effect of the aggregate contents, aggregate morphological features and aggregate distributions on the fracture behavior of asphalt concrete in different fracturing modes at different temperatures. The results show that the fracture toughness and the crack extended time reduce with the increasing aggregate orientation and flatness and the decreased aggregate content. The effect of aggregate flatness is nonlinear, and its reduction trend grows gradually with the increasing flatness. The total number of failed contacts is reduced with the increasing aggregate orientation and flatness, particularly at 10 °C. The number of failed contacts that occurred in the aggregate–mastic interface in Quasi-Mode II fracturing is slightly higher than that in other fracturing modes. The aggregate distribution in the crack initiation zone greatly influenced the crack resistance, particularly at 10 °C. The research is beneficial to better understand the fracture mechanisms of asphalt concrete at low-temperature

    Laboratory evaluation of PE modified asphalt mixture containing reclaimed asphalt pavement

    Get PDF
    83-88This study evaluated the pavement performances of polyethylene (PE) modified asphalt mixture (PEHMA) containing reclaimed asphalt pavement (RAP). A series of RAP (80-100 wt%) were added into PEHMA to replace natural aggregate for the manufacture of RAP–PEHMA. Marshall design method was employed to prepare related specimens to determine the permanent deformation, water sensitivity, low temperature crack resistance and fatigue properties. The results show that RAP–PEHMA performs better rutting resistance than the PEHMA (control mixture), which means that the RAP could improve the high temperature performance of PEHMA. Conversely, RAP–PEHMA made with PE and RAP displays worse water stability, low temperature stability, fatigue performance than that of PEHMA, but all of them could satisfy the current mixture requirements in China

    Adalimumab exhibits superiority over etanercept in terms of a numerically higher response rate and equivalent adverse events: A real‐world finding

    No full text
    Abstract Introduction Adalimumab (ADA) and etanercept (ETN) are the most commonly applied biologics for rheumatoid arthritis (RA) management in China; however, the evidence regarding their superiority is controversial. In addition, in real‐world clinical settings, many factors may affect the application of these agents, such as dosage and administration period. Therefore, the present real‐world study aimed to compare the efficacy and safety of ADA and ETN treatment in RA patients via the propensity score matching method. Methods In total, 105 RA patients receiving ADA (n = 66) or ETN (n = 39) were reviewed in this retrospective study. The propensity score matching method was used to eliminate discrepancies in baseline features. Clinical response, low disease activity (LDA), and remission were evaluated based on the DAS28. Results Before propensity score matching, compared with ETN, ADA yielded higher rates of clinical response at W24 (97.0% vs. 84.6%, p = .021), LDA at W12 (78.8% vs. 51.3%, p = .003), and remission at W24 (75.8% vs. 46.2%, p = .002). After propensity score matching, compared with ETN, ADA only achieved a higher rate of clinical response at W24 (96.3% vs. 77.8%, p = .043), whereas the rates of LDA and remission were not different between ADA and ETN treatments at any time point (all p > .05). In addition, the incidence of adverse events was not significantly different between the ADA and ETN treatments (all p > .05). Conclusion ADA shows superiority over ETN in terms of a numerically greater response rate and equivalent adverse events

    Acupuncture May Be a Potential Complementary Therapy for Alzheimer’s Disease: A Network Meta-Analysis

    No full text
    With Alzheimer’s disease (AD) becoming a worldwide problem, traditional Chinese medicine (TCM), especially acupuncture, stands out as a complementary therapy because of its feature—“treatment based on syndrome differentiation”. This systematic review and network meta-analysis (NMA) confirms the complement effect of acupuncture and explores the best combination of therapy for AD based on the total effect and activity of daily living scale (ADL). We searched relevant randomized controlled trials (RCTs) that applied acupuncture for treating AD. 58 studies with 4334 patients were included in accordance with PRISMA guidelines. The results showed that for the total effect, the order of probability for the effect: acupuncture + western medicine > acupuncture + herbal medicine > acupuncture > acupuncture + western medicine + herbal medicine. For the ADL score, the order of probability for the effect: acupuncture + western medicine > acupuncture > acupuncture + western medicine + herbal medicine > acupuncture + herbal medicine. The combination of acupuncture and medicine has a better clinical effect than acupuncture only in a way. Acupuncture + western medicine has an obvious and exact improvement in the curative effect from both total effect and ADL score, but further higher quality studies, which can detail the classification of these interventions, are still needed to verify it

    The Detection of Flood Characteristics Alteration Induced by the Danjiangkou Reservoir at Han River, China

    No full text
    As one of the most common natural phenomena, floods can bring both risks and benefits for human beings. They can pose a risk of inundation to a human habitat but can also be utilized as a resource with hydraulic engineering. Improving the knowledge of flood characteristics is the basis and premise of improving water resources management and ecological environmental protection. Presently, the quantitative evaluation of flood characteristics needs to gradually evolve from a single indicator to a systematic one. In this paper, by introducing the concepts of ecohydrology on magnitude, frequency, and duration, a set of flood characteristics indicators evaluation system is constructed based on the hydrological characteristics for the section where Danjiangkou Reservoir is located at the middle reach of the Yangtze in China. The results showed that the Danjiangkou Reservoir has changed the flood characteristics to a great extent both of seasonal or annual floods, and the mean degree of the flood characteristic alteration indicators is about 19%. The changing trend of the flood indicators upstream showed an increasing trend from the 1970s to 2010s, while downstream were divided into two periods by the year of about 1975. The methodological system provided by this paper can effectively evaluate flood characteristics quantitatively, provide technical guidance and a useful reference for flood process analysis, and provide support for flood management and river ecosystem protection
    corecore