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The cell is the unit of life for all organisms, and all cells are certainly not the same. So the technology to generate transcription expression or genomic DNA profiles from single cells is crucial. Since its establishment in 2009, single-cell RNA sequencing (scRNA-seq) has emerged as a major driver of progress in biomedical research. During the last three years, several new single-cell sequencing platforms have emerged. Yet there are only a few systematic comparisons of the advantages and limitations of these commonly used platforms. Here we compare two single-cell sequencing platforms: BD Rhapsody and 10x Genomics Chromium, including their different mechanisms and some scRNA-seq results obtained with them.

A spatial data interpolation algorithm is a method to transform scattered and sparse measurement data into regular and continuous applicable data. This algorithm can make the display results smooth and continuous without changing the data characteristics, which is closer to the real acquisition object. In response to the low interpolation accuracy of the inverse distance weighting (IDW) algorithm and the poor interpolation efficiency of the ordinary kriging (OK) algorithm, this study proposes a variational-weighted (VW) interpolation algorithm based on data fixed-frame sampling. By introducing the variational function of OK into IDW and taking different weight coefficients from OK, a new computational model is constructed to improve the interpolation accuracy and adapt to different types of data characteristics. In the whole interpolation process, the data are sampled in a fixed frame and a new sampling point search method is proposed to improve the computational efficiency. The study not only compares the accuracy and efficiency of the algorithm using two types of data but also tests the stability of the new algorithm for different data volumes. It is shown that VW based on a fixed-grid sampling of the data is more accurate than the inverse distance interpolation algorithm for both data types. The VW interpolation algorithm based on data lattice sampling improves the computational efficiency for featureless data and exhibits better performance in terms of accuracy and computational efficiency for data with features, compared to the common kriging interpolation algorithm. In addition, the VW interpolation algorithm based on a fixed-grid sampling of data has a more stable performance for different amounts of data.

With the continuous development of scientific visualization, visualization has been applied to various fields. Flow field visualization is an important part of the visual field, by using computer graphics, computer vision, and image processing technology, it can use intuitive graphical images to describe the flow field structure of the complex, disorder, which makes the flow field visualization in the field of meteorology, aviation and geography have great application prospect. This paper uses MATLAB App Designer to design a flow field visualization software, which mainly displays the scalar or vector velocity field in two dimensions and three dimensions. The software has a powerful interactive function, can choose different flow field display modes, can choose a specific two-dimensional section for separate display. With this software, flow field data can be clearly, succinctly, and intuitively displayed, and key information such as flow field distribution, movement trend, and velocity change can be understood. In addition, the software uses MATLAB App Designer to encapsulate the form of desktop independent APP, which is simple and convenient to use.

Uniform near-spherical nanoscale silver films (NSFs) as a very sensitive and stable SERS-active substrate were synthesized by a facile and efficient in situ liquid–solid–solid (LSS) reaction method...

In the visual simulation of surface dust concentration in virtual campus, the concentration data of each grid point should be obtained. Because the surface dust concentration data grid points are unknown, so through the discrete sample point grid points around the known surface dust concentration properties of the unknown point grid point value interpolation estimation. Therefore, it is very important to select an interpolation algorithm that can satisfy the requirement of the accuracy of the surface dust concentration and have high computational efficiency in the interpolation process of unknown points. According to the data characteristics of virtual campus surface dust concentration value, this paper proposes an inverse distance mixed interpolation algorithm for interpolation by combining the advantages of the inverse distance weighted interpolation method and the kriging interpolation algorithm, and compares the calculation results of inverse distance mixed interpolation with the traditional interpolation algorithm. The results show that inverse distance mixed interpolation algorithm not only has high accuracy, but also runs efficiently.

The evaluation of software quality involves many factors, therefore it is difficult to get a scientific and reasonable quantitative evaluation results. Based on the analysis of the advantages and disadvantages of AHP method and EM method, this paper proposes a fuzzy comprehensive evaluation model to evaluate the software system. The model uses the weight calculation method based on AHP-EM to overcome the defects of single weight assignment method. By evaluating the 3D visualization software system based on web, it can be seen that the evaluation result based on AHP-EM fuzzy comprehensive evaluation model is closer to the subjective evaluation conclusion than the evaluation results using single weight calculation method, which proves the validity and practicability of the evaluation method, and provides a useful theoretical reference for improving the software quality.

Fundamental to viral biology is identification and annotation of viral genes and their function. Determining the level of coronavirus gene expression is inherently difficult due to the positive stranded RNA genome and the identification of subgenomic RNAs (sgRNAs) that are required for expression of most viral genes. We developed a bioinformatic pipeline to analyze metatranscriptomic data from 20 independent studies encompassing 588 individual samples and 10 coronavirus species. This comparative analysis defined a core sgRNA repertoire for SARS-CoV-2 and found novel sgRNAs that could encode functional short peptides. Relevant to coronavirus infectivity and transmission, we also observed that the ratio of Spike sgRNA to Nucleocapsid one is highest in SARS-CoV-2, among the β-coronaviruses examined. Furthermore, the adjustment of this ratio can be made by modifications to the viral RNA replication machinery, representing a form of viral gene regulation that may be involved in host adaption.