Perceptron ensemble of graph-based positive-unlabeled learning for disease gene identification

Identification of disease genes, using computational methods, is an important issue in biomedical and bioinformatics research. According to observations that diseases with the same or similar phenotype have the same biological characteristics, researchers have tried to identify genes by using machine learning tools. In recent attempts, some semi-supervised learning methods, called positive-unlabeled learning, is used for disease gene identification. In this paper, we present a Perceptron ensemble of graph-based positive-unlabeled learning (PEGPUL) on three types of biological attributes: gene ontologies, protein domains and protein-protein interaction networks. In our method, a reliable set of positive and negative genes are extracted using co-training schema. Then, the similarity graph of genes is built using metric learning by concentrating on multi-rank-walk method to perform inference from labeled genes. At last, a Perceptron ensemble is learned from three weighted classifiers: multilevel support vector machine, k-nearest neighbor and decision tree. The main contributions of this paper are: (i) incorporating the statistical properties of gene data through choosing proper metrics, (ii) statistical evaluation of biological features, and (iii) noise robustness characteristic of PEGPUL via using multilevel schema. In order to assess PEGPUL, we have applied it on 12950 disease genes with 949 positive genes from six class of diseases and 12001 unlabeled genes. Compared with some popular disease gene identification methods, the experimental results show that PEGPUL has reasonable performance.     

青铜器有害锈变温XRD及热分析

根除或有效控制氯化亚铜（CuCl）是青铜器保护的关键技术.根据铜的氯化物在一定温度下易分解或挥发这一性质,本文利用热分析仪及X射线衍射（XRD）手段,对CuCl粉末进行了分析,结果表明在大气环境中加热到420--430℃熔融后易挥发,实验结果将为寻找通过局部加热消除青铜基体内有害锈“病灶体”的合适方法提供依据.     

Nanobioelectroanalysis Based on Carbon/Inorganic Hybrid Nanoarchitectures

The emergence of nanotechnology has opened new horizons for electrochemical biosensors. This review highlights new concepts for electrochemical biosensors based on different carbon/inorganic hybrid nanoarchitectures. Particular attention will be given to hybrid nanostructures involving 1‐ or 2‐dimensional carbon nanotubes or graphene along with inorganic nanoparticles (gold, platinum, quantum dot (QD), metal oxide). Latest advances (from 2007 onwards) in electrochemical biosensors based on such hybrids of carbon/inorganic‐nanomaterial heterostructures are discussed and illustrated in connection to enzyme electrodes for blood glucose or immunoassays of cancer markers. Several strategies for using carbon/inorganic nanohybrids in such bioaffinity and biocatalytic sensing are described, including the use of hybrid nanostructures for tagging or modifying electrode transducers, use of inorganic nanomaterials as surface modifiers along with carbon nanomaterial label carriers, and carbon nanostructure‐based electrode transducers along with inorganic amplification tags. The implications of these nanoscale bioconjugated hybrid materials on the development of modern electrochemical biosensors are discussed along with future prospects and challenges.     

Silicon nanowire biosensor and its applications in disease diagnostics: A review

Over the past decade, silicon nanowire (SiNW) biosensors have been studied for the detection of biological molecules as highly sensitive, label-free, and electrical tools. Herein we present a comprehensive review about the fabrication of SiNW biosensors and their applications in disease diagnostics. We discuss the detection of important biomarkers related to diseases including cancer, cardiovascular diseases, and infectious diseases. SiNW biosensors hold great promise to realize point-of-care (POC) devices for disease diagnostics with potential for miniaturization and integration.     

Korrosion von Messing und Bronze durch Ammoniumhalogenide

Corrosion of Brass and Bronze by Ammonium Halides The intermetallic phases brass (Cu/Zn) and bronze (Cu/Sn) are corroded by ammonium fluoride and chloride, NH₄F and NH₄Cl, through selective oxidation of the less noble component zinc and tin, respectively. Copper is recrystallized as cube‐like or tabular single crystals under the respective influence of fluoride and chloride. Zinc and tin are incorporated in complex compounds of which (NH₄)ZnF₃, (NH₄)₂ZnF₄, Zn(NH₃)₂Cl₂ and (NH₄)₃SnF₇ were detected by X‐ray powder diffraction.     

病害胁迫下棉花叶片色素含量高光谱遥感估测研究

通过小区和大田同步调查棉花黄萎病,在不同生育期测定病叶光谱及其色素含量。将病叶光谱反射率、一阶微分及相应的特征参数与色素含量进行相关分析,建立病叶色素含量估测模型并检验。结果表明：病叶叶绿素a,b及a+b含量可见光反射率、与一阶微分光谱在蓝边、黄边和红边处与除红边振幅(Dr)外的其他光谱特征参数间均达极显著相关。转换叶绿素吸收反射指数(TCARI)和新建归一化植被指数(NDVI[702, 758])对叶绿素a, b及a+b含量的估测精度最高,相对误差均小于1.3%。考虑到NDVI[702, 758]建立的模型更实用,可做为病叶叶绿素a, b和a+b含量的最佳估测模型。研究结果对高光谱信息定量估测病害棉叶色素含量,对利用高光谱监测棉花长势及病害影响评价均具有较高的实用价值。     

Soyasapogenol-B as a Potential Multitarget Therapeutic Agent for Neurodegenerative Disorders: Molecular Docking and Dynamics Study

Neurodegenerative disorders involve various pathophysiological pathways, and finding a solution for these issues is still an uphill task for the scientific community. In the present study, a combination of molecular docking and dynamics approaches was applied to target different pathways leading to neurodegenerative disorders such as Alzheimer’s disease. Initially, abrineurin natural inducers were screened using physicochemical properties and toxicity assessment. Out of five screened compounds, a pentacyclic triterpenoid, i.e., Soyasapogenol B appeared to be the most promising after molecular docking and simulation analysis. Soyasapogenol B showed low TPSA (60.69), high absorption (82.6%), no Lipinski rule violation, and no toxicity. Docking interaction analysis revealed that Soyasapogenol B bound effectively to all of the targeted proteins (AChE, BuChE MAO-A, MAO-B, GSK3β, and NMDA), in contrast to other screened abrineurin natural inducers and inhibitors. Importantly, Soyasapogenol B bound to active site residues of the targeted proteins in a similar pattern to the native ligand inhibitor. Further, 100 ns molecular dynamics simulations analysis showed that Soyasapogenol B formed stable complexes against all of the targeted proteins. RMSD analysis showed that the Soyasapogenol B–protein complex exhibited average RMSD values of 1.94 Å, 2.11 Å, 5.07 Å, 2.56 Å, 3.83 Å and 4.07 Å. Furthermore, the RMSF analysis and secondary structure analysis also indicated the stability of the Soyasapogenol B–protein complexes.     

用直读光谱仪测定铝青铜中铝,铁,锰

本文介绍了直读光谱仪直接测定铝青铜中铝，铁，锰三元素的方法，选择和确定了最佳工作条件，通过一套铜合金国家标准样品作出校准曲线，此法快速，准确，简便，分析结果令人满意。     

用于间质液检测的微针阵列研究进展

间质液是疾病诊断生物标志物的重要来源。微针阵列作为一种微创技术进入皮下间质液可以避免接触血管和神经,使用时疼痛感较小,易被患者接受,在多种领域都有广泛的应用。使用微针阵列检测间质液可以为临床诊断提供更多信息,研发制备简单、稳定性强和功能多样的微针阵列逐渐成为研究热点。本文介绍了间质液中生物标志物检测对人体健康监测的重要意义,总结了用于间质液检测的微针阵列的分类以及微针阵列制备所使用材料,着重介绍了微针阵列在间质液中采样与检测应用,讨论了微针阵列在间质液检测中的发展前景以及面临的挑战。