ABSTRACT
OBJECTIVES@#To establish a rapid and nondestructive identification method for human body fluid stains and non-biological stains using three-dimensional fluorescence spectroscopy.@*METHODS@#The collected three-dimensional fluorescence spectrum data of human saliva, 3% blood, coffee and Fanta® stains were processed with dimensionality reduction. After wavelet transform, spectral denoising and feature extraction, the classification formula was established. The Fisher discriminant was used for spectrum matching and recognition to establish the analysis method to distinguish stain types.@*RESULTS@#According to the results of data training and comparison, all the recognition accuracies of Fanta®, coffee, saliva and blood were more than 91.39%. Among them, saliva reached 100% recognition accuracy.@*CONCLUSIONS@#Three-dimensional fluorescence spectroscopy is a potential method for rapid and nondestructive identification of biological and non-biological stains.
Subject(s)
Humans , Forensic Medicine/methods , Coloring Agents/analysis , Coffee , Spectrometry, Fluorescence , Body Fluids/chemistryABSTRACT
OBJECTIVE@#To improve DNA extraction from human epithelium.@*METHODS@#Chelex-100, Chelex-100 organic combined and Chelex-100 magnetism pearl combined methods were adopted according to the situation of each case.@*RESULTS@#With the stepwise extracting protocol, the trace amount of DNA was analyzed most efficiently and the success rate of DNA extracting was better improved.@*CONCLUSION@#The efficiency of DNA extraction from human epithelium could be greatly improved by modifying the extracting protocol such as purification and concentration based on previous results.
Subject(s)
Humans , DNA/isolation & purification , Epithelial Cells/cytology , Forensic Genetics , Polymerase Chain Reaction/methods , Resins, Synthetic/chemistryABSTRACT
Two endophytic-bacteria isolates of G18 and F19 were isolated from the stem of Taxus chinensis. The G18 and F19 were respectively classified into Psudomonas sp. and Stenotrophomonas sp. based on biological characteristics and 16S rDNA sequence analysis. The bioactivity analysis showed that the fermented broths of the G18 and F19 exhibited antagonistic activities against three pathogenic bacteria, and had good antagonistic effectiveness to Verticillium dahliae and Colletotrichum gloeosporioides, respectively. The G18 can degrade salicylic acid, and the F19 can do dichlorvos.