23 research outputs found

    A novel chaotic time series prediction method and its application to carrier vibration interference attitude prediction of stabilized platform

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    Aiming at the problems existing in previous chaos time series prediction methods, a novel chaos times series prediction method, which applies modified GM(1, 1) model with optimizing parameters to study evolution laws of phase point L1 norm in reconstructed phase space, is proposed in this paper. Phase space reconstruction theory is used to reconstruct the unobserved phase space for chaotic time series by C-C method, and L1 norm series of phase points can be obtained in the reconstructed phase space. The modified GM(1, 1) model, which is improved by optimizing background value and optimizing original condition, is used to study the change law of phase point L1 norm for forecasting. The measured data from stabilized platform experiment and three traditional chaos time series are applied to evaluate the performance of the proposed model. To test the prediction method, three accuracy evaluation standards are employed here. The empirical results of stabilized platform are encouraging and indicate that the newly proposed method is excellent in prediction of chaos time series of chaos systems

    Dust emission reduction enhanced gas-to-particle conversion of ammonia in the North China Plain

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    Liu et al. found that the formation rate of particulate ammonium is slower in the atmosphere than that observed in the laboratory, while it is sped up due to an increase in aerosol acidity driven by an emission reduction of dust in North China Plain.Ammonium salt is an important component of particulate matter with aerodynamic diameter less than 2.5 mu m (PM2.5) and has significant impacts on air quality, climate, and natural ecosystems. However, a fundamental understanding of the conversion kinetics from ammonia to ammonium in unique environments of high aerosol loading is lacking. Here, we report the uptake coefficient of ammonia (gamma(NH3)) on ambient PM2.5 varying from 2.2 x 10(-4) to 6.0 x 10(-4) in the North China Plain. It is significantly lower than those on the model particles under simple conditions reported in the literature. The probability-weighted gamma(NH3) increases obviously, which is well explained by the annual decrease in aerosol pH due to the significant decline in alkali and alkali earth metal contents from the emission source of dust. Our results elaborate on the complex interactions between primary emissions and the secondary formation of aerosols and the important role of dust in atmospheric chemistry.Peer reviewe

    Lenalidomide or bortezomib as maintenance treatment remedy the inferior impact of high-risk cytogenetic abnormalities in non-transplant patients with newly diagnosed multiple myeloma: a real-world multi-centered study in China

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    Maintenance treatment is a pivotal part in the whole process management of multiple myeloma (MM), which further deepens response and improves survival. However, evidence of maintenance in non-transplant MM patients is inadequate in real-world practice. Here, we retrospectively analyzed the efficacy and survival of 375 non-transplant MM patients from 11 centers between 2010 and 2021 in north China. After a median of seven cycles of front-line regimens, there were 141, 79, and 155 patients receiving lenalidomide maintenance (L-MT), bortezomib maintenance (B-MT), or thalidomide maintenance (T-MT), respectively. Patients on L-MT and B-MT had significantly greater proportions of high-risk cytogenetic abnormalities (HRCAs) detected by fluorescence in situ hybridization (FISH), which was defined as 1q21 gain, 17p deletion, adverse immunoglobulin heavy chain (IgH) translocations. Although the progression-free survival (PFS) and overall survival (OS) were comparable among the three groups, L-MT and B-MT remedied the negative impact of HRCAs on survival (PFS of patients with HRCAs vs. patients without HRCAs: L-MT, 26.9 vs. 39.2 months, p=0.19; B-MT, 20.0 vs. 29.7 months, p=0.36; OS not reached in all groups). Patients with HRCAs in the T-MT group presented inferior clinical outcomes compared to standard-risk patients (PFS, 12.1 vs. 22.8 months, p=0.02, HR=1.8, 95% CI 1.0–3.4; OS, 54.9 months vs. NR, p<0.001, HR=3.2, 95% CI 1.5–7.0). Achieving complete response (CR) after induction therapy led to superior PFS compared to other degrees of response, regardless of maintenance medication. Furthermore, maintenance duration over 24 months correlated with favorable survival. Due to the large gap of transplant eligibility in China, optimizing maintenance therapy is important for non-transplant MM patients. In this real-world multi-centered study, our findings suggest that clinicians prefer to prescribe lenalidomide or bortezomib as maintenance therapy in high-risk settings, which are superior to thalidomide in non-transplant MM patients. Achievement of CR and maintenance duration over 2 years are positive factors that influence survival

    Surveillance of antifungal susceptibilities in clinical isolates of Candida species at 36 hospitals in China from 2009 to 2013

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    Background: The purpose of this study was to determine the species distribution and to monitor the antifungal susceptibility profiles of clinical Candida isolates collected in China from 2009 to 2013. Methods: The antifungal susceptibilities of 952 Candida isolates were tested. Results: Candida albicans was the most common species, accounting for 65.7% of the total isolates. The most frequently isolated non-albicans Candida species in this study was Candida glabrata (193, 20.3%). Nearly 7.6%, 3.2%, 1.8%, and 1.1% of the 952 isolates exhibited decreased susceptibility to fluconazole, voriconazole, itraconazole, and flucytosine, respectively. Moreover, seven C. albicans and one Candida krusei had an amphotericin B minimum inhibitory concentration (MIC) of 2 μg/ml. Conclusions: The distribution of species and the prevalence of antifungal resistance in Candida isolates varied among different areas in China. Continuous monitoring of resistance patterns is necessary to control the spread of resistance in clinical isolates of Candida species

    Single-Cell Sequencing Analysis Identified ASTN2 as a Migration Biomarker in Adult Glioblastoma

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    Glioblastoma is the most common and aggressive primary central nervous system malignant tumors. With the development of targeted sequencing and proteomic profiling technology, some new tumor types have been established and a series of novel molecular markers have also been identified. The 2021 updated World Health Organization classification of central nervous system tumors first mentioned the classification of adult glioma and pediatric glioma based on the molecular diagnosis. Thus, we used single-cell RNA sequencing analysis to explore the diversity and similarities in the occurrence and development of adult and pediatric types. ASTN2, which primarily encodes astrotactin, has been reported to be dysregulated in various neurodevelopmental disorders. Although some studies have demonstrated that ASTN2 plays an important role in glial-guided neuronal migration, there are no studies about its impact on glioblastoma cell migration. Subsequent single-cell RNA sequencing revealed ASTN2 to be a hub gene of a cell cluster which had a poor effect on clinical prognosis. Eventually, a western blot assay and a wound-healing assay first confirmed that ASTN2 expression in glioblastoma cell lines is higher than that in normal human astrocytes and affects the migration ability of glioblastoma cells, making it a potential therapeutic target

    Response of AFP, CIRP, HMGB1 and YB-1 Gene of Takifugu rubripes to Low-Temperature Stress

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    Environmental conditions regulate the growth and reproduction of fish. The increase in sea temperature during winter may have adverse effects on Takifugu rubripes. To study the mechanism of low-temperature tolerance of T. rubripes, the expression of antifreeze protein (AFP) gene, cold-induced RNA binding protein (CIRP) gene, high mobility group protein box-1 (HMGB1) gene, and Y-box binding protein (YB-1) gene in the liver, spleen, kidney, brain, heart, intestine, muscle, gonad, and skin tissues of T. rubripes obtained from different temperatures (18℃, 13℃, 8℃, and 5℃) was analyzed by quantitative real-time PCR. The results showed that the AFP gene was widely expressed in tissues, with the highest expression in the muscle (P < 0.05). With the decrease in temperature, the expression of the AFP gene in each tissue showed a significant increasing trend, reaching the highest value in the 5℃ group. The expression of the CIRP gene was the highest in the muscle (P < 0.05). With a decrease in temperature, the trend of CIRP gene expression in various tissues was different. The CIRP gene expression levels of liver, kidney, brain, heart, intestine, and skin showed a trend of initial increase, followed by a decrease, and then an increase. The expression levels in the spleen, muscle, and gonads showed an upward trend, reaching the highest value in the 5℃ group. The expression of the HMGB1 gene was the highest in muscle (P < 0.05), followed by that in the brain, liver, heart and skin. As the temperature decreased, the expression of the HMGB1 gene in all tissues except the liver increased first and then decreased, and reached the maximum value in the 8℃ group, which was significantly higher than that of the other groups (P < 0.05). The expression of the YB-1 gene was the highest in the muscle (P < 0.05), with the lowest expression level in other tissues. As the temperature decreased, the expression level of most tissues (brain, heart, intestine, kidney, liver, muscle, and spleen) increased first, then decreased, and then increased, reaching the minimum value in the 8℃ group (P < 0.05). These results show that the expression levels of the four genes are different at different temperature, reflecting the functional specificity of these four genes. Under low-temperature stress, these genes responded positively. Their expression changed to varying degrees, suggesting that the four genes may have potentially important roles in the adaptation of T. rubripes to low temperatures. In addition, by analyzing the law of gene expression, 8℃ may be the key regulatory point for T. rubripes to deal with low-temperature stress. Too low temperature may cause its regulation disorder. The results of this study can provide a relevant basis for studying the regulation mechanism of the low-temperature response of T. rubripes

    A S-Scheme MOF-on-MOF Heterostructure

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    Constructing MOF-on-MOF heterojunction with elaborate charge transfer mechanism and interface is a promising strategy for improving the photocatalytic properties of MOFs. Herein, a Step-scheme (S-scheme) MIL-125-NH2@CoFe Prussian blue analogue (PBA) heterojunction is reported for the first time. The MOF-on-MOF heterostructure exhibits a sandwich-like morphology with hollow CoFe PBA nanocages selectively assembled on the top-down surfaces of MIL-125-NH2 nanocakes. Experimental findings and theoretical simulation results reveal the formation of internal electric field via interfacial Ti-O-Co bonds at the heterojunction, providing driving force and atomic transportation highway for accelerating the S-scheme charge transfer and enhancing the redox performance. Contributed further by the hollow sandwich-like structures with increased active site exposure, the designed MOF-on-MOF heterojunction exhibits significantly enhanced photocatalytic activity for degradation of various organic pollutants. This study provides insights toward the rational design of semiconducting MOF-based heterojunctions with improved properties.</p
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