Dynamic Characteristics of DC Motor Controlled by Thyristor Chopper Circuit

A theoretical method to analyse the steady and dynamic characteristics of a separately excited dc motor controlled by a thyristor chopper circuit is introduced. In the analysis, the influences of the fluctuations of the dc motor speed and the armature current during one cycle of a chopper frequency on the characteristics are considered. The characteristic equation in the control circuit is derived theoretically, and it is then denoted that the circuit performance can be described by an equivalent sampled data system. Next, the validity of the theoretical method is verified by ascertaining that the calculated results agree well with the experimental results. Furthermore, the influences of the circuit parameters and the situation of an armature current on the motor performances are investigated. Finally, the sampled data system is applied to investigate the frequency response of the motor, which has not been investigated in the usual papers

Psychosocial factors associated with smoking and drinking among Japanese early adolescent boys and girls: Cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Smoking and drinking alcohol among early adolescents are serious public health concerns, but few studies have been conducted in Japan to assess their prevalence and etiology. A regional survey was conducted in eight schools in two Japanese school districts to identify psychosocial factors associated with smoking and drinking behaviors for boys and girls.</p> <p>Methods</p> <p>Junior high school students from seventh to ninth grades (N = 2,923) completed a self-reported questionnaire between December 2002 and March 2003. Relationships between psychosocial variables (i.e., self-assertive efficacy to resist peer pressure, parental involvement, school adjustment, and deviant peer influence) and smoking and drinking were investigated using logistic regression analyses and path analyses.</p> <p>Results</p> <p>Smoking in the last six months was significantly more prevalent in boys (7.9%) than girls (5.1%). The prevalence of drinking in the last six months was similar in boys (23.7%) and girls (21.8%). Self-efficacy to resist peer pressure was negatively associated with both smoking and drinking among both boys and girls and provided both direct and indirect effects through deviant peer influence. Parental involvement showed indirect effects through school adjustment and/or deviant peer influence to both smoking among both boys and girls and drinking among girls, although parental involvement showed direct effects on smoking only for boys. School adjustment was negatively associated with smoking among both boys and girls and drinking among girls.</p> <p>Conclusion</p> <p>These findings suggest that self-assertive efficacy to resist peer pressure, parental involvement, school adjustment and deviant peer influence are potentially important factors that could be addressed by programs to prevent smoking and/or drinking among early adolescent boys and girls in Japan.</p

Aberrant Methylation of p21 Gene in Lung Cancer and Malignant Pleural Mesothelioma

Suppression of p21 has been implicated in the genesis and progression of many human malignancies. DNA methylation is an important mechanism of gene silencing in human malignancies. In this study, we examined the expression status and aberrant methylaion of p21 in lung cancers and malignant pleural mesotheliomas (MPM). We used 12 small cell lung cancer (SCLC) cell lines, 13 non-small cell lung cancer (NSCLC) cell lines, 50 primary NSCLCs, 6 MPM cell lines and 10 primary MPMs. The expression and methylation of p21 was examined by reverse transcription-PCR (RT-PCR), Western blotting and methylation-specific PCR (MSP) assay. Loss of p21 protein expression was observed in 7 SCLC cell lines (58.3%), 5 NSCLC cell lines (38.5%) and 3 MPM cell lines (50%) while mRNA expression was lost in 2 SCLC cell lines (16.7%), 2 NSCLC cell lines (15.4%) and none of the MPM cell lines. Aberrant methylation of p21 was found in 8.3% of SCLC cell lines, 30.2% of NSCLCs and 6.3% of MPMs. Among primary NSCLCs, methylation in adenocarcinomas was significantly more frequent than in squamous cell carcinomas. Loss of p21 expression was frequently observed in lung cancers and MPMs and aberrant methylation was one of the mechanisms of suppression of p21, especially in NSCLCs

A Single Gene Expression Set Derived from Artificial Intelligence Predicted the Prognosis of Several Lymphoma Subtypes; and High Immunohistochemical Expression of TNFAIP8 Associated with Poor Prognosis in Diffuse Large B-Cell Lymphoma

OBJECTIVES: We have recently identified using multilayer perceptron analysis (artificial intelligence) a set of 25 genes with prognostic relevance in diffuse large B-cell lymphoma (DLBCL), but the importance of this set in other hematological neoplasia remains unknown. METHODS AND RESULTS: We tested this set of genes (i.e., ALDOB, ARHGAP19, ARMH3, ATF6B, CACNA1B, DIP2A, EMC9, ENO3, GGA3, KIF23, LPXN, MESD, METTL21A, POLR3H, RAB7A, RPS23, SERPINB8, SFTPC, SNN, SPACA9, SWSAP1, SZRD1, TNFAIP8, WDCP and ZSCAN12) in a large series of gene expression comprised of 2029 cases, selected from available databases, that included chronic lymphocytic leukemia (CLL, n = 308), mantle cell lymphoma (MCL, n = 92), follicular lymphoma (FL, n = 180), DLBCL (n = 741), multiple myeloma (MM, n = 559) and acute myeloid leukemia (AML, n = 149). Using a risk-score formula we could predict the overall survival of the patients: the hazard-ratio of high-risk versus low-risk groups for all the cases was 3.2 and per disease subtype were as follows: CLL (4.3), MCL (5.2), FL (3.0), DLBCL not otherwise specified (NOS) (4.5), multiple myeloma (MM) (5.3) and AML (3.7) (all p values 60 years, high serum levels of soluble IL2RA, a non-GCB phenotype (cell-of-origin Hans classifier), moderately higher MYC and Ki67 (proliferation index), and high infiltration of the immune microenvironment by CD163-positive tumor associated macrophages (CD163+TAMs). CONCLUSIONS: It is possible to predict the prognosis of several hematological neoplasia using a single gene-set derived from neural network analysis. High expression of TNFAIP8 is associated with poor prognosis of the patients in DLBCL

High Expression of Caspase-8 Associated with Improved Survival in Diffuse Large B-Cell Lymphoma: Machine Learning and Artificial Neural Networks Analyses

High expression of the anti-apoptotic TNFAIP8 is associated with poor survival of the patients with diffuse large B-cell lymphoma (DLBCL), and one of the functions of TNFAIP8 is to inhibit the pro-apoptosis Caspase-8. We aimed to analyze the immunohistochemical expression of Caspase-8 (active subunit p18; CASP8) in a series of 97 cases of DLBCL from Tokai University Hospital, and to correlate with other Caspase-8 pathway-related markers, including cleaved Caspase-3, cleaved PARP, BCL2, TP53, MDM2, MYC, Ki67, E2F1, CDK6, MYB and LMO2. After digital image quantification, the correlation with several clinicopathological characteristics of the patients showed that high protein expression of Caspase-8 was associated with a favorable overall and progression-free survival (Hazard Risks = 0.3; p = 0.005 and 0.03, respectively). Caspase-8 also positively correlated with cCASP3, MDM2, E2F1, TNFAIP8, BCL2 and Ki67. Next, the Caspase-8 protein expression was modeled using predictive analytics, and a high overall predictive accuracy (&gt;80%) was obtained with CHAID decision tree, Bayesian network, discriminant analysis, C5 tree, logistic regression, and Artificial Intelligence Neural Network methods (both Multilayer perceptron and Radial basis function); the most relevant markers were cCASP3, E2F1, TP53, cPARP, MDM2, BCL2 and TNFAIP8. Finally, the CASP8 gene expression was also successfully modeled in an independent DLBCL series of 414 cases from the Lymphoma/Leukemia Molecular Profiling Project (LLMPP). In conclusion, high protein expression of Caspase-8 is associated with a favorable prognosis of DLBCL. Predictive modeling is a feasible analytic strategy that results in a solution that can be understood (i.e., explainable artificial intelligence, “white-box” algorithms)

Artificial Neural Networks Predicted the Overall Survival and Molecular Subtypes of Diffuse Large B-Cell Lymphoma Using a Pancancer Immune-Oncology Panel

Diffuse large B-cell lymphoma (DLBCL) is one of the most frequent subtypes of non-Hodgkin lymphomas. We used artificial neural networks (multilayer perceptron and radial basis function), machine learning, and conventional bioinformatics to predict the overall survival and molecular subtypes of DLBCL. The series included 106 cases and 730 genes of a pancancer immune oncology panel (nCounter) as predictors. The multilayer perceptron predicted the outcome with high accuracy, with an area under the curve (AUC) of 0.98, and ranked all the genes according to their importance. In a multivariate analysis, ARG1, TNFSF12, REL, and NRP1 correlated with favorable survival (hazard risks: 0.3–0.5), and IFNA8, CASP1, and CTSG, with poor survival (hazard risks = 1.0–2.1). Gene set enrichment analysis (GSEA) showed enrichment toward poor prognosis. These high-risk genes were also associated with the gene expression of M2-like tumor-associated macrophages (CD163), and MYD88 expression. The prognostic relevance of this set of 7 genes was also confirmed within the IPI and MYC translocation strata, the EBER-negative cases, the DLBCL not-otherwise specified (NOS) (High-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements excluded), and an independent series of 414 cases of DLBCL in Europe and North America (GSE10846). The perceptron analysis also predicted molecular subtypes (based on the Lymph2Cx assay) with high accuracy (AUC = 1). STAT6, TREM2, and REL were associated with the germinal center B-cell (GCB) subtype, and CD37, GNLY, CD46, and IL17B were associated with the activated B-cell (ABC)/unspecified subtype. The GSEA had a sinusoidal-like plot with association to both molecular subtypes, and immunohistochemistry analysis confirmed the correlation of MAPK3 with the GCB subtype in another series of 96 cases (notably, MAPK3 also correlated with LMO2, but not with M2-like tumor-associated macrophage markers CD163, CSF1R, TNFAIP8, CASP8, PD-L1, PTX3, and IL-10). Finally, survival and molecular subtypes were successfully modeled using other machine learning techniques including logistic regression, discriminant analysis, SVM, CHAID, C5, C&R trees, KNN algorithm, and Bayesian network. In conclusion, prognoses and molecular subtypes were predicted with high accuracy using neural networks, and relevant genes were highlighted

High PTX3 expression is associated with a poor prognosis in diffuse large B-cell lymphoma

Tumor-associated macrophages (TAMs) are associated with a poor prognosis of diffuse large B-cell lymphoma (DLBCL). As macrophages are heterogeneous, the immune polarization and their pathological role warrant further study. We characterized the microenvironment of DLBCL by immunohistochemistry in a training set of 132 cases, which included 10 Epstein–Barr virus-encoded small RNA (EBER)-positive and five high-grade B-cell lymphomas, with gene expression profiling in a representative subset of 37 cases. Diffuse large B-cell lymphoma had a differential infiltration of TAMs. The high infiltration of CD68 (pan-macrophages), CD16 (M1-like), CD163, pentraxin 3 (PTX3), and interleukin (IL)-10-positive macrophages (M2c-like) and low infiltration of FOXP3-positive regulatory T lymphocytes (Tregs) correlated with poor survival. Activated B cell-like DLBCL was associated with high CD16, CD163, PTX3, and IL-10, and EBER-positive DLBCL with high CD163 and PTX3. Programmed cell death-ligand 1 positively correlated with CD16, CD163, IL-10, and RGS1. In a multivariate analysis of overall survival, PTX3 and International Prognostic Index were identified as the most relevant variables. The gene expression analysis showed upregulation of genes involved in innate and adaptive immune responses and macrophage and Toll-like receptor pathways in high PTX3 cases. The prognostic relevance of PTX3 was confirmed in a validation set of 159 cases. Finally, in a series from Europe and North America (GSE10846, R-CHOP-like treatment, n = 233) high gene expression of PTX3 correlated with poor survival, and moderately with CSF1R, CD16, MITF, CD163, MYC, and RGS1. Therefore, the high infiltration of M2c-like immune regulatory macrophages and low infiltration of FOXP3-positive Tregs is associated with a poor prognosis in DLBCL, for which PTX3 is a new prognostic biomarker