Current status and future perspectives in bioinformatical analysis of Hi-C data.

The spatial interaction of chromosomes is regarded as an important issue affecting the regulation of gene expression, and the high-throughput chromosome conformation capture (Hi-C) technology has become the primary tool to explore the temporal and spatial interactions of chromosomes in three-dimensional genomics. With the continuous accumulation of Hi-C samples and the increasing complexity of pipelines, the bioinformatic analysis of Hi-C data has been considered an opportunity and a challenge for understanding the spatial regulation mechanism of gene expression. In this paper, the current status and development outline of bioinformatic methods for Hi-C data are introduced, including data normalization, multi-level structure analysis, data visualization and 3D modeling, especially of multi-level structure at A/B compartments, topological associated domains (TADs) and chromain looping levels. Based on this, we provide the outlook of future hotspots and trends in this area. Hopefully our insight will be beneficial for the exploration of gene expression regulation from the traditional linear model to the 3D mode.

[A research of stability method for non-dispersive infrared gas analysis based on multi-parameter model].

To non-dispersive infrared gas analysis, it was the most difficult challenge to maintain very low zero and temperature drift over long periods. Electronic and detector response drifts irremediably required some form of manual zeroing procedure. To solve zero and temperature drift, a multi-parameters model was developed, by which zero and temperature drifts were automatically corrected. These parameters include zero gas intensity, reference channels intensity, standard temperature, environment temperature, temperature drift coefficients etc. Trial results and in-situ applications showed that the monitoring precisions of the instrument were lesser than 5% F. S in different temperatures and for a long time. The average precision of monitoring carbon monoxide concentration increased respectively from 9.26 to 1.23%, and monitoring hydrocarbon concentration from 10.61% to 0.70% before and after compensated. The instrument required essentially no periodic calibration and have very low maintenance cost.

[An integrated on-line processing method for spectrometric data based on wavelet transform and Gaussian fitting].

Miniature mobile field spectrometry is pivotal equipment for qualitative and quantitative in-situ analysis of chemical substances. To solve the problem of spectrum signal interfered by complicated noise, overlapped and irregular peak shape recognition, and quick monitoring, an integrated on-line processing method for spectrometric data based on wavelet transform and Gaussian fitting was developed. In this way, toluene and perfluorotributylamine were processed, and the results shows that the integrated method can powerfully and effectively eliminate the noise, retain the original feature, and correct the overlapped and asymmetrical peaks, which can improve the analysis accuracy of instrument, and also achieve data compression. In addition, the method satisfies the requirement of on-site analysis for mobile field spectrometry. For the processing of mass spectra of toluene, at the characteristic peaks of 91 and 92, the SNR increased 1.3 times compared to that of moving average smoothing method, while the error between original peaks and theoretic peaks decreased 3.6 times. In addition, Gaussian fitting described the multipoint mass spectra data by three Gaussian parameters, and achieved data compression. For the processing of mass spectrogram of perfluorotributylamine, the ratio of compression was 197 : 1.