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In order to improve the stability and prediction accuracy of a Laser Induced Breakdown Spectroscopy (LIBS) quantitative analysis model a chemometrics method named PSO-SVM (particle swarm optimization-support vector machine) is proposed for the quantitative prediction of heavy metal chromium (Cr) in pork by analyzing the spectral data obtained by LIBS. The usable spectral region from 424.77 to 429.99 nm was identified. The normalized preprocessing of spectra was employed. Also, the spectral dimension was reduced through principal component analysis (PCA). The PSO algorithm was applied to select the SVM hyper-parameters including the regularization and kernel parameters. The calibration model of heavy metal Cr in pork was established using the optimum hyper-parameters obtained by PSO-SVM. The performance of this PSO-SVM model was compared with a synergy interval partial least squares (siPLS) model and a multilayer perceptron artificial neural network (MLP-ANN). The feasibility of these three methods was examined on the test sample set. The experimental results showed that the proposed method (PSO-SVM) achieved better prediction accuracy robustness compared with the other two quantitative analysis methods. The calibration results of siPLS and MLP-ANN models are similar, and the fitting degree of the siPLS modeling effect is not high, while the MLP-ANN verification results are not ideal. For the PSO-SVM model, the correlation coefficients (R2) of the calibration and validation sets were higher than 0.99. The mean absolute percentage error (MAPE) of the calibration set is 0.0792%, and the MAPE of the validation set is 1.9395%. The RMSE values of the calibration and validation sets were 0.0245% and 0.6961%, respectively, which were much lower than the other two models. This investigation displayed that the PSO-SVM algorithm exhibited excellent model robustness and prediction accuracy. There is definite practical significance and application value in the monitoring of meat safety by analyzing LIBS data coupled with PSO-SVM methods. [ABSTRACT FROM AUTHOR]

In hypotrichous ciliates, macronuclear chromosomes are gene-sized, and micronuclear genes contain short, noncoding internal eliminated segments ( IESs) as well as macronuclear-destined segments ( MDSs). In the present study, we characterized the complete macronuclear gene and two to three types of micronuclear actin genes of two urostylid species, i.e. Pseudokeronopsis rubra and Uroleptopsis citrina. Our results show that (1) the gain/loss of IES happens frequently in the subclass Hypotrichia (formerly Stichotrichia), and high fragmentation of germline genes does not imply for gene scrambling; and (2) the micronuclear actin gene is scrambled in the order Sporadotrichida but nonscrambled in the orders Urostylida and Stichotrichida, indicating the independent evolution of MIC-actin gene patterns in different orders of hypotrichs; (3) locations of MDS- IES junctions of micronuclear actin gene in coding regions are conserved among closely related species. [ABSTRACT FROM AUTHOR]

Abstract: A new piecewise-polynomial interface method (PIM) for discretizing elliptic problems with complex interfaces between high-contrast materials is derived, analyzed and tested. A Krylov-accelerated interface multigrid approach (IMG) solves the discretization efficiently. Stability and convergence are proved in one dimension, while an extensive array of numerical experiments with complex interfaces and large coefficient transitions demonstrate the accuracy, efficiency and robustness of the method in two dimensions. [Copyright &y& Elsevier]

Abstract: The thermodynamic stability of device-relevant epitaxial SiGe strained layers under proton irradiation is investigated using X-ray diffraction techniques, and compared with its stability constrain under high-temperature annealing. Irradiation with 63MeV protons is found to introduce no significant microdefects into the SiGe thin films, regardless of starting stability condition of the SiGe film, and thus does not appear to be an issue for the use of SiGe HBT technology in emerging space systems. The strain relaxation of SiGe thin film under thermal annealing, however, is sensitive to the composition and thickness of the as-grown samples, as expected, with the subsequent lattice relaxation of the unstable samples occurring at a much higher rate than that of metastable samples. [Copyright &y& Elsevier]

Abstract: We investigate the reliability issues associated with the application of CMOS devices contained within an advanced SiGe HBT BiCMOS technology to emerging cryogenic space electronics (e.g., down to 43K, for Lunar missions). Reduced temperature operation improves CMOS device performance (e.g., transconductance, carrier mobility, subthreshold swing, and output current drive), as expected. However, operation at cryogenic temperatures also causes serious device reliability concerns, since it aggravates hot-carrier effects, effectively decreasing the inferred device lifetime significantly, especially at short gate lengths. In the paper, hot-carrier effects are demonstrated to be a stronger function of the device gate length than the temperature, suggesting that significant trade-offs between the gate length and the operational temperature must be made in order to ensure safe and reliable operation over typical projected mission lifetimes in these hostile environments. [Copyright &y& Elsevier]

The radiation response of SiO2 gate oxides grown on 4H-SiC to NO passivation is presented for the first time. The effects of gamma radiation on Qeff are similar for n-4H-SiC MOS capacitors both with and without NO passivation, but are different in sign (negative) compared to SiO2 on Si. The variation in Dit with total dose, however, is different for the passivated versus the unpassivated samples. Comparisons between Si SOI and 4H-SiC suggest that properly passivated SiC MOSFETs should have good radiation tolerance. [Copyright &y& Elsevier]

Many studies have revealed the crucial roles of miRNA in multiple human cancers, including lung adenocarcinoma (LUAD). In this study, we sought to explore new miRNA-mRNA pairs that are associated with LUAD prognosis. A novel miRNA-mRNA regulatory network associated with prognosis in LUAD was identified and validated using the bioinformatic tools including OncomiR database, StarBase, miRnet, GEPIA2, UALCAN. Twenty key miRNAs were compiled after the analysis of the expression and prognostic value in OncomiR and StarBase. Targeted mRNAs of these key miRNAs were predicted in miRnet, and the resulting mRNAs were also analyzed for their prognostic values and expression patterns in GEPIA2 and UALCAN, respectively. Further expression correlation analysis was performed in StarBase. Subsequently, a new miRNA-mRNA network was built, of which each RNA pair showed negative expression correlation, opposite expression pattern, and prognostic value. Protein-protein interaction network was under construction for the mRNAs, and 19 hub genes were determined. Enrichment analysis showed that "Cell Cycle, Mitotic" was the most significantly enriched term. Then, a miRNA-hub gene sub-network was built. We selected and validated the regulatory relationship of some miRNA-hub pairs, including hsa-miR-1976/RFC2, hsa-let-7c-5p/RFC2, hsa-let-7c-5p/ESPL1, hsa-let-7c-5p/CDC25A, and hsa-miR-101-3p/KIF2C. Moreover, over-expression of hsa-miR-1976 and hsa-let-7c-5p resulted in significant cell cycle arrest. Our results determined new prognosis-associated miRNA-mRNA pairs and might shed further light on the mechanism via which miRNA-mRNA network influences prognosis in LUAD. [ABSTRACT FROM AUTHOR]

To improve the accuracy of laser-induced breakdown spectroscopy (LIBS) in the classification of tea leaves, a modified adaptive mutation probability for genetic algorithm (GA) was proposed to optimize support vector machines (SVM). The implementation process of the GA-SVM algorithm was discussed, and the key parameters were analyzed. The penalty factor and kernel function parameters in SVM were optimized by GA. The spectral line intensities of Mg (279.55 nm), Mn (279.83 nm), Mg (280.27 nm), CN (0–0) (388.34 nm), Ca (393.37 nm), Al (396.15 nm), Ca (396.84 nm), C2 (0–0) (516.45 nm), Fe (517.46 nm) and K (766.49 nm) compared to C (247.86 nm) were selected as the analysis indexes according to the differences of LIBS spectra. LIBS spectra pre-processed by multiple scattering correction (MSC) with the optimal input feature were used to construct the GA-SVM model for different tea species. The results showed that the average correct classification rate was 99.73% in the training set. In addition, the average accuracy was 98.40% in the test set. The classification accuracy of the improved GA-optimized SVM was obviously higher than that of cross validation-support vector machine (CV-SVM) and particle swarm optimization-support vector machine (PSO-SVM). This work demonstrates that the GA-SVM can avoid the blindness of parameter selection and can effectively increase the accuracy of tea classification. The results indicated that LIBS is an effective technology in identificating tea leaves; moreover, it has a real-time, rapid and reliable measurement prospect. [ABSTRACT FROM AUTHOR]

Long non‐coding RNAs (lncRNAs) play key roles in various biological processes. However, the roles of lncRNAs in macrophage polarization remain largely unexplored. In this study, thousands of lncRNAs were identified that are differentially expressed in distinct polarized bone marrow‐derived macrophages. Among them, Dnmt3aos (DNA methyltransferase 3A, opposite strand), as a known lncRNA, locates on the antisense strand of Dnmt3a. Functional experiments further confirmed that Dnmt3aos were highly expressed in M(IL‐4) macrophages and participated in the regulation of Dnmt3a expression, and played a key role in macrophage polarization. The DNA methylation profiles between the Dnmt3aos knockdown group and the control group in M(IL‐4) macrophages were determined by MeDIP‐seq technique for the first time, and the Dnmt3aos‐Dnmt3a axis‐mediated DNA methylation modification‐regulated macrophage polarization‐ related gene IFN‐γ was identified. Our study will help to enrich our knowledge of the mechanism of macrophage polarization. [ABSTRACT FROM AUTHOR]

In this work, laser-induced breakdown spectroscopy (LIBS), near-infrared spectroscopy (NIR), and LIBS joint NIR (LIBS–NIR) were investigated for the identification of citrus huanglongbing (HLB). The content of minerals like calcium (Ca), zinc (Zn), and potassium (K) was obtained by atomic absorption spectroscopy (AAS). The spectra of LIBS, NIR, and LIBS–NIR were operated by discriminating analysis (DA) and multi-layer perception (MLP). The results of AAS and Kolmogorov–Smirnov Test (K–S test) showed that the Ca and Zn decreased significantly in HLB infected leaves, but K is not significantly influence by HLB. The LIBS–NIR combining with MLP-PCA had highest diagnostic accuracy of 89.5% and 95.7% in training and test set, respectively. These results proved that joint spectrum of LIBS–NIR is a feasible method to identify citrus HLB. [ABSTRACT FROM AUTHOR]

Tto explore the stress effect of heavy-metal Cu on other minerals in rice, the laser-induced breakdown spectroscopy (LIBS) fingerprint information of typical mineral elements in husk under different Cu stress was studied. A total of 24 rice grains samples with the same variety were collected in Dexing, Yanshan, Guixi of Jiangxi province, China. The results demonstrated that the LIBS spectral intensity of Cu in rice was highest in Dexing, followed by Yanshan and Guixi. The phenomenon was consistent with the reference concentration of Cu in rice and soil obtained by atomic absorption spectroscopy (AAS). The results were consistent with the corresponding reference concentration of Cu in rice and soil. Data processing was used to analyze the distribution of mineral elements Zn, Mn, Fe, Mg, Si, and K in Cu-stressed rice. The prediction precision of minerals based on the intensity ratio between internal calibration line Ca II 393.366 nm and objective minerals was considered. And PLS model was established. The results showed that the corresponding ratio including Zn, Mn, Fe, Mg, Si, and K increased with the increase of Cu stress, which displayed a positive correlation. Moreover, the intensity ratios of Zn, Mn, Fe, Si, and K in rice under different degrees of Cu stress were significantly distinct. This investigation indicated that LIBS coupled with suitable calculation can realize early rapid diagnosis of heavy-metal Cu stress in rice and provide technical support for comprehensive prevention and control of heavy-metal pollution in crops. [ABSTRACT FROM AUTHOR]

Background: Glioblastoma multiforme (GBM) is the most seriously brain tumor with extremely poor prognosis. Recent research has demonstrated that competitive endogenous RNA (ceRNA) network which long noncoding RNAs (lncRNAs) act as microRNA (miRNA) sponges to regulate mRNA expression were closely related to tumor development. However, the regulatory mechanisms and functional roles of ceRNA network in the pathogenesis of GBM are remaining poorly understood. Methods: In this study, we systematically analyzed the expression profiles of lncRNA and mRNA (GSE51146 dataset) and miRNA (GSE65626 dataset) from GEO database. Then, we constructed a ceRNA network with the dysregulated genes by bioinformatics methods. The TCGA and GSE4290 dataset were used to confirm the expression and prognostic value of candidate mRNAs. Results: In total, 3413 differentially expressed lncRNAs and mRNAs, 305 differentially expressed miRNAs were indentified in GBM samples. Then a ceRNA network containing 3 lncRNAs, 5 miRNAs, and 60 mRNAs was constructed. The overall survival analysis of TCGA databases indicated that two mRNAs (C1s and HSD3B7) were remarkly related with the prognosis of GBM. Conclusion: The ceRNA network may increase our understanding to the pathogenesis of GBM. In general, the candidate mRNAs from the ceRNA network can be predicted as new therapeutic targets and prognostic biomarkers for GBM. [ABSTRACT FROM AUTHOR]

• Mice deficient in AK085865 are protected from Der f1-induced allergic airway inflammation. • AK085865 deletion in M2 macrophages is the major cause of decreased susceptibility of AA induced by Der f1. • The percentage of ILC2s is reduced in AK085865−/− mice, possibly due to a decrease in the number of M2 macrophages. • Knockout of AK085865 in M2 macrophages has no significant effect on promoting ILCP differentiation into ILC2s. • M2 macrophages promote the differentiation of ILCP into ILC2s, probably through the exosomal pathway. Accumulating evidence indicates that regulators of macrophages polarization may play a key role in the development of allergic asthma (AA). However, the exact role of long non-coding RNAs (lncRNAs) in regulating in macrophages polarization in the pathogenesis of dermatophagoides farinae protein 1(Der f1)-induced AA is not fully understood. The purpose of this study was to determine the function of lncRNA AK085865 in regulating macrophages in AA. Here we report that lncRNA AK085865 served as a critical regulator of macrophages polarization and reduced the pathological progress of asthmatic airway inflammation. In response to the challenge of Der f1, AK085865−/− mice displayed attenuated allergic airway inflammation, including decreased eosinophil in BALF and reduced production of IgE, which were associated with decreased mucous glands and goblet cell hyperplasia. In addition, Der f1-treated AK085865−/− mice show fewer M2 macrophages when compared with WT asthmatic mice. After adopting bone marrow-derived macrophages (BMDM, M0) from WT mice, Der f1-treated AK085865−/− mice also revealed a light inflammatory reactions. We further observed that the percentage of type II innate immune lymphoid cells (ILC2s) decreased in AK085865−/− asthmatic mice. Moreover, M2 macrophages helped promote the differentiation of ILC2s, probably through the exosomal pathway secreted by M2 macrophages. Taken together, these findings reveal that AK085865 depletion can ameliorate asthmatic airway inflammation by modulating macrophage polarization and M2 macrophages can promote the differentiation of innate lymphoid cells progenitor (ILCP) into ILC2s. [ABSTRACT FROM AUTHOR]