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In this study, an embryogenic callus induction and proliferation system for Hippeastrum vittatum was established, with the tender bulbs as expiants. And then the sensitivity of the expiants and calli to kanamycin and hygromycin was evaluated. The results suggested that the embryogenic calli were induced from tender bulbs and cultured in Murashige and Skoog (MS) medium supplemented with 0.5 mg/L N-phenyl-N'-l, 2,3-thiadiazol-5-ylurea (TDZ), 1.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D), and 30 g/L sucrose (pH5.8) in the dark at 25 ± 1°C. Further study of the influence of kanamycin and hygromycin on callus induction and multiplication showed that, the lethal doses of kanamycin and hygromycin to bulb expiants were 100 and 30 mg/L, respectively. All expiants of H. vittatum died on the medium supplemented with 100 mg/L kanamycin or 30 mg/L hygromycin at the induction stage, and callus proliferation was completely inhibited by 100 mg/L kanamycin or 25 mg/L hygromycin, and all the calli died at last. These results will provide important reference for further studies of transgenic H. vittatum. [ABSTRACT FROM AUTHOR]

In order to improve the evaluation accuracy of political classroom teaching quality in universities, a DA-BP-based evaluation method of political classroom teaching quality in universities is proposed. First of all, in constructing the teaching quality evaluation system of university political courses using the framework of behavior theory, the system consists of 4 primary indicators and 15 secondary indicators. Second, the university's 2008–2013 annual teaching quality assessment scores for the teaching quality of political courses were used as the input data of the DA-BP network, and the 2013–2016 teaching evaluation scores were used as the algorithm's test data. In order to test the prediction accuracy of the DA-BP algorithm, it is compared with the GA-BP algorithm, PSO-BP algorithm, and BP algorithm. The research results show that DA-BP has higher prediction accuracy than other algorithms and can better evaluate the teaching quality of political courses. [ABSTRACT FROM AUTHOR]

Tribochemistry refers to a series of physical and chemical reactions that occur at a sliding interface under friction action, and the tribological properties of materials also change significantly. Understanding the effect of tribochemical reactions on the tribological properties of materials is important for controlling the structure and composition of materials by chemical means and promoting the engineering application of materials. This study primarily introduces the tribochemical reactions of diamond-like carbon (DLC) films during the friction process in different environments and the relationship between tribochemistry and the tribological properties of DLC films. From this, the study proposes strategies to achieve the superlubricity of DLC films through tribochemistry. Finally, challenges and countermeasures in the engineering application of DLC films are discussed. [ABSTRACT FROM AUTHOR]

Background: Insertion/deletion polymorphisms (InDels), combined with all the desirable features of both short tandem repeat and single nucleotide polymorphism, have been used in archaeological and anthropological research, population genetics and forensic application. Methods: Thirty InDels in 530 individuals residing in the Tibetan‐Yi corridor (142 Dujiangyan Tibetans, 164 Muli Tibetans, 187 Xichang Yis, and 37 Yanyuan Mosuos) were genotyped using the Investigator DIPplex. Forensic parameters and allele frequency spectrum were calculated. Genetic relationships between the investigated populations and worldwide and nationwide populations were assessed based on both the allele frequency distribution and genotype data. Results: The combined powers of exclusion were 0.9807 (Dujiangyan Tibetan), 0.9880 (Muli Tibetan), 0.9852 (Xichang Yi) and 0.9892 (Yanyuan Mosuo). The combined powers of discrimination were 0.999999999983 (Dujiangyan Tibetan), 0.999999999942 (Muli Tibetan), 0.999999999982 (Xichang Yi) and 0.999999999962 (Yanyuan Mosuo), respectively. The comprehensive population comparisons among worldwide and nationwide populations uniformly illustrated that the investigated populations have a genetically closer relationship with Tibeto‐Burman‐speaking populations and geographically adjacent populations. Conclusion: These 30 loci can be regarded as an efficient genetic tool in forensic individual identification and as a supplementary tool in paternity testing in Dujiangyan Tibetan, Muli Tibetan, Xichang Yi, and Yanyuan Mosuo. The genetic proximity between the four populations in the Tibetan‐Yi corridor and other populations is strongly correlated with the linguistic origin and geographical distance. [ABSTRACT FROM AUTHOR]

Insertion/deletion (Indel) genetic markers have special features compared to other forensic-related markers, such as the low mutation rate and di-allelic markers with length polymorphism, playing an indispensable role in the forensic and population genetics, molecular anthropology and evolutionary biology. However, the genetic diversity, allelic frequency, forensic parameters and population genetic characteristics of the Indel markers in Hmong–Mien-speaking Guizhou Miao people are unclear due to the sparse sampling. Thus, we genotyped 30 forensic-related Indel markers in 311 unrelated healthy Miao individuals (149 females and 161 males) residing in the Guizhou Province in Southwest China using the Investigator DIPplex amplification system. All 30 Indels are in accordance with the no departures of Hardy–Weinberg equilibrium and linkage disequilibrium. The combined probability of discrimination and the probability of exclusion in Guizhou Miao population are 0.999999999948 and 0.9843, respectively. This observed ideal forensic parameter estimates indicate that this di-allelic Indel panel can be used as a supplementary tool in forensic retinue personal identification and complemented for autosomal STRs in the parentage testing in Miao population, especially used as the main tool in old or highly degraded samples in disaster victim identification. Eleven Indels show a high allele frequency difference between different continental populations and could be used as ancestry-informative markers in forensic ancestry inference. Phylogenetic relationships between Guizhou Miao and 68 worldwide populations based on the genetic polymorphisms of Indels are investigated via three different pairwise genetic distances, principal component analysis, multidimensional scaling analysis and phylogenetic relationship reconstructions. Analyses of the comprehensive population genetic relationship comparison reveal significant genetic differentiation of Chinese groups. Our results demonstrate that Guizhou Miao people are genetically closer related to the geographically adjacent populations, especially with Liangshan Yi, Guangxi Miao and Dong, but genetically distinct with Turkic-speaking populations. Comprehensive and precise genetic admixture and divergence history of Guizhou Miao and neighboring populations are needed to further investigate and reconstruct via high-density marker panel or whole-genome sequencing of modern or ancient Miao samples. [ABSTRACT FROM AUTHOR]

China, inhabited by over 1.3 billion people and known for its genetic, cultural and linguistic diversity, is considered to be indispensable for understanding the association between language families and genetic diversity. In order to get a better understanding of the genetic diversity and forensic characteristics of Tai–Kadai-speaking populations in Southwest China, we genotyped 30 insertion/deletion (InDel) markers and amelogenin in 205 individuals from Tai–Kadai-speaking Bouyei people using the Qiagen Investigator DIPplex amplification kit. We carried out a comprehensive population genetic relationship investigation among 14,303 individuals from 84 worldwide populations based on allele frequency correlation and 4907 genotypes of 30 InDels from 36 populations distributed in all continental or major subregions and seven linguistic phyla in China. Forensic parameters observed show highly polymorphic and informative features for Asians, although the DIPplex kit was developed focusing on Europeans, and indicate that this amplification system is appropriate to forensic personal identification and parentage testing. Patterns of InDel variations revealed by principal components analysis, multidimensional scaling plots, phylogenetic relationship exploration, model-based clustering as well as four pairwise genetic distances (Fst, Nei, Cavalli-Sforza and Reynolds) demonstrate significant genetic differentiation at the continental scale and genetic uniformity in Asia except for Tibeto-Burman and Turkic-speaking populations. Additionally, Tai–Kadai speakers, including Bouyei, Zhuang and Dong, share more genetic ancestry components than with other language speakers, and in general they are genetically very similar to Hmong–Mien-speaking populations. The dataset of Bouyei people generated in the present study is valuable for forensic identification and parentage tests in China. [ABSTRACT FROM AUTHOR]