Search

With the widespread use of the Y chromosome in genetics, a lot of commercially available Y chromosome kits were developed, validated, and applied to forensic science practice. The AGCU YNFS Y Kit is a new Y chromosome system containing forty-four preferred Y short tandem repeats (Y-STRs) and five common Y-InDels. In this study, the AGCU YNFS Y system was validated to verify its performance by following the guidelines of the Scientific Working Group on DNA Analysis Methods (SWGDAM). A series of validation experiments included the following parameters: PCR-based studies, sensitivity studies, species specificity studies, stability studies, mixture studies, precision studies, stutter calculation, mutation and statistical analysis, population study, and case samples and degradation studies. The results suggested that appropriately changing PCR amplification conditions did not affect genotyping; the kit had good sensitivity for trace amounts of DNA (0.0625 ng), mixtures of multiple male individuals (minor: major = 1: 9), and three PCR inhibitors (more than 250 μM hematin, 250 ng/μL humic acid and 50 ng/μL tannic acid). The maximum standard deviation of allele size did not exceed 0.1552 reflecting the high accuracy of the system. By this, 87 DNA-confirmed pairs of father-son pairs were also analyzed for mutations. A total of 18 loci were mutated, with mutation rates ranging from 11.5×10−3 to 34.5×10−3 (95% CI 7.2×10−3–97.5×10−3, DYS627 and DYF404S1). In the population study, the haplotype diversity of 87 unrelated individuals was 0.9997, and discrimination capacity was 0.9885. Degradation studies have demonstrated that UV-C light exposure for up to 120 hours has no effect on male blood and semen-vaginal secretion mixtures. However, complete typing could no longer be obtained after 48 hours of UV exposure in single male saliva and in male saliva and female blood mixed samples. Collectively, the AGCU YNFS Y Kit is sensitive and accurate and can play its application value in forensic science practice. [ABSTRACT FROM AUTHOR]

Objective: This work was aimed to analyze the effect of vitamin energy drink on muscle fatigue by surface electromyography (SEMG) and ultrasonic bioimaging (USBI). Methods: 20 healthy men were selected to do increasing load fatigue test. Surface electromyographic signals and ultrasonic biological images were collected based on wavelet threshold function with improved thresholds. Time domain and frequency domain characteristic integrated electromyography (IEMG), root mean square amplitude (RMS), average power frequency (MPF), and surface and deep muscle morphological changes were analyzed. Hemoglobin concentration (HB), red blood cell number (RBC), mean volume of red blood cell (MCV), blood lactic acid (BLA), malondialdehyde (MDA), and phosphocreatine kinase (CK) were measured. Results: 1) the Accuracy (94.10%), Sensitivity (94.43%), Specificity (93.75%), and Precision (94.07%) of the long and short-term memory (LSTM) specificity for muscle fatigue recognition were higher than those of other models. 2) Compared with the control group, the levels of BLA, MDA, and CK in the experimental group were decreased and HB levels were increased after exercise (P < 0.05). 3) IEMG and RMS of the experimental group were higher than those of the control group, and increased with time (P < 0.05). 4) The mean amplitude of the response signal decreased with time. Compared with the control group, the surface muscle thickness, deep muscle thickness, total muscle thickness, contrast, and homogeneity (HOM) decreased in the experimental group; while the angular second moment (ASM) and contrast increased, showing great differences (P < 0.05). Conclusion: Surface electromyographic signal and ultrasonic biological image can be used as auxiliary monitoring techniques for muscle fatigue during exercise. Drinking vitamin energy drinks before exercise can relieve physical fatigue to a certain extent and promote the maintenance of muscle microstructure. [ABSTRACT FROM AUTHOR]