Molecular and phylogenetic analysis of Anaplasma spp. in sheep and goats from six provinces of China

Yan Zhang,Yali Lv,Feifei Zhang,Wenjing Zhang,Jinhong Wang,Yanyan Cui,Rongjun Wang,Fuchun Jian,Longxian Zhang,Changshen Ning 대한수의학회 2016 Journal of Veterinary Science Vol.17 No.4

Members of the genus Anaplasma are important emerging tick-borne pathogens in both humans and animals in tropical and subtropical areas. Here, we investigated the presence of Anaplasma spp. in 621 sheep and 710 goats from six provinces of China. Polymerase chain reaction(PCR) and DNA sequencing were conducted to determine the prevalence of Anaplasma (A.) phagocytophilum, A. ovis and A. bovis targetingthe 16S ribosomal RNA or the major surface protein 4 gene. PCR revealed Anaplasma in 39.0% (240/621) of sheep and 45.5% (323/710)of goats. The most frequently detected species was A. ovis (88/621, 14.2% for sheep; 129/710, 18.2% for goats), followed by A. bovis (60/621,9.7% for sheep; 74/710, 10.4% for goats) and A. phagocytophilum (33/621, 5.3% for sheep; 15/710, 2.1% for goats). Additionally, eight sheepand 20 goats were found to be infected with three pathogens simultaneously. DNA sequencing confirmed the presence of these three Anaplasmaspecies in the investigated areas, and phylogenetic analysis indicated that there was geographic segregation to a certain extent, as well as arelationship between the host and cluster of A. ovis. The results of the present study provide valuable data that helps understand theepidemiology of anaplasmosis in ruminants from China.

Chinese University Students’ and Teachers’ Perceptions of and Attitudes towards ELF

( Yanyan Zhang ),( Xingkun Du ) 범태평양 응용언어학회 2018 범태평양응용언어학회지 Vol.22 No.2

It has been widely acknowledged in the academic field that English is being used as a lingua franca among people from various first language backgrounds. However, the notion of English as a Lingua Franca (ELF) does not seem to have been integrated into English classrooms, especially in China, a country from the Expanding Circle. As China has the largest population of learners of English as a foreign language, the current study aims to investigate university students’ and teachers’ perceptions of and attitudes towards ELF in the Chinese context. A total of 168 non-English major students and 30 college English teachers from a top university in Mainland China participated in the study. Two questionnaires were distributed to our student and teacher participants, respectively, and a semi-structured interview was organized afterwards. It was found that neither the students nor the teachers have sufficient knowledge about ELF, despite their awareness of the lingua franca function of English. Both the students and the teachers appear to be deeply attached to “Standard English” under the influence of “native speaker norm” in English teaching contents and methods. However, the students hold highly positive attitudes towards ELF and express their willingness to learn about it in class. Therefore, it is of vital importance for English teachers to reconsider their beliefs and teaching practices and try to incorporate an ELF orientation into English teaching.

Room-temperature Synthesis of Cu2O Nanostructures and Their Morphology-dependent Adsorption Properties

Yanyan Xu,Ping Liu,Yanyan Cao,Yaqiu Sun,Guoying Zhang 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.7

Three different Cu2O nanostructures, namely porous nanospheres, nanoparticles, and nanocubes, were synthesized through a facile solution route at room temperature. Structure and morphology of the products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FESEM), and nitrogen adsorption–desorption isotherms. The adsorption behavior of Methyl Orange (MO) onto these Cu2O nanostructures was investigated, considering the effect of initial methyl orange concentration and the additive amount of Cu2O products. The kinetic and equilibrium investigations suggested that the adsorption process of MO followed a pseudo-second order rate equation and the Langmuir isotherm model. The maximum adsorption capacity of the three samples followed the sequence: porous nanospheres > nanoparticles > nanocubes, which was in accordance of the BET specific surface of the samples. In addition, further investigations indicated that the as-prepared Cu2O nanostructures also show good adsorption properties for other anionic dyes including Congo red and Methyl blue.

Effect of MoS2 on Iron‑Based Friction Material Prepared Directly from Vanadium‑Bearing Titanomagnetite Concentrates

Yanyan Zhang,Keqin Feng,Yue Shui 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.7

The iron-based friction material was prepared directly from vanadium-bearing titanomagnetite concentrates by in situ selectivecarbothermic reactions and sintering process. This paper studies the effects of MoS2addition (1–4 wt%) on the microstructureand properties of iron-based friction material. The results show that the addition of MoS2greatly improves themicrostructure and properties of the material. During the sintering process, MoS2reacts with Fe to produce new lubricatingphase FeS and Mo which is dissolved in the Fe matrix. Appropriate amounts of FeS and Mo promote the sintering densification,which improves the microstructure by reducing the number of pores, as well as making the hard particles and graphitedistribute evenly. In addition, Mo could facilitate the formation of lamellar pearlite. As a result, the relative density, hardnessand tribological properties are significantly enhanced. Particularly, the friction coefficient decreases from 0.55 to 0.36–0.48and the wear rate decreases from 1.899 × 10−7 to 0.673 × 10−7–1.653 × 10−7 cm3/J when MoS2is added. However, excessiveMoS2deteriorates both the microstructure and properties of the material. The material containing 2 wt% MoS2representsthe optimum properties.

An Investigation of Chinese EFL Learners’ Perceived Comprehensibility of Nine English Accents

Yanyan Zhang 범태평양 응용언어학회 2019 범태평양응용언어학회지 Vol.23 No.2

With the emergence of different varieties of English in the world, the issue of intelligibility has attracted many researchers’ attention. While a large number of studies have focused on the intelligibility of different English varieties for native speakers, few of them have involved Chinese learners of English as participants; yet, they constitute the largest group of non-native English speakers. The current study aims to investigate Chinese university students’ perceived comprehensibility, i.e., intelligibility judgments, of nine English accents, including British, American, Australian, Indian, Philippine, Singaporean, French, Japanese, and South Korean English. Thirty-nine English major sophomores from a top university in China were invited to identify the speakers’ nationalities and assign ratings for their perceived comprehensibility of the nine English accents. A follow-up semi-structured interview was also undertaken. It was found that all of the participants could identify American English and most of them could also recognize British, Australian and South Korean English. In contrast, they could hardly recognize the other five English accents. With regard to perceived comprehensibility, the Inner Circle English accents on the whole are significantly more comprehensible than the Outer Circle and Expanding Circle English accents. Chinese university students’ perceived comprehensibility significantly correlates with properties of the speech. Moreover, it was observed that familiarity with English accents and speech properties may interplay and influence perceived comprehensibility. The study contributes to the ongoing literature on intelligibility and provides pedagogical implications for English education.

Study of oil-particle-aggregation by digital inline holograph

Wei Zhang,Xinsheng Yu,Jian Zhang,Yanyan Wang 한국지질과학협의회 2019 Geosciences Journal Vol.23 No.3

This study was performed to visually analyse the relationship between particles and oil in seawater by digital holograph technology. Two types of particles with different sizes were chosen to form oil-particle aggregates (OPAs) in the laboratory to determine whether these particles may be a good approach to safely and harmoniously recover marine environment after an oil spill. The processes were recorded by a digital inline holographic system, which could facilitate a continuous real-time three-dimensional in situ observation of oil droplets and OPAs without touching these particles. The visual results showed that, in the micro scale, the particles formed two different types of OPA after breaking the oil film and transported oil into the bottom of the water, while some OPAs could be resuspended.

1-methylcyclopropene treatment improves postharvest quality and antioxidant activity of Prunus domestica L. cv. Ximei fruit

Ma Yanyan,Zhang Weida,CHENGSHAOBO,Yang Wanting,Liu Yuxing,Yang Shengyu,Zhang Xinling,Guo Minrui,Chen Guogang 한국원예학회 2022 Horticulture, Environment, and Biotechnology Vol.63 No.6

Prunus domestica L. cv. Ximei fruit perishes quickly due to intense metabolic activity after being harvested. To prolong shelf life and maintain fruit quality, the eff ects of 1-methylcyclopropene (1-MCP) treatment on P. domestica fruit during storage at 4 ± 1 °C were investigated. The results showed that the soluble solid content (SSC), respiratory rate (29.8%), ethylene production (27.2%), anthocyanin content, malonaldehyde content (MDA), hydrogen peroxide content (H 2O2), and superoxide anion activity (O 2·−) of P. domestica fruit were all signifi cantly reduced by 1-MCP treatment (1.0 μL L −1), while the content of ascorbic acid and total phenol, and the activity of SUPEROXIDE DISMUTASE (SOD, 61.3%), CATALASE (CAT, 39.0%), ASCORBATE PEROXIDASE (APX, 23.7%), and PEROXIDASE (POD, 38.0%) increased compared to untreated fruit after 35 days of cold storage. Overall, 1-MCP treatment could maintain high postharvest quality and anti- oxidant activity in P. domestica fruit

Robot Subgoal-guided Navigation in Dynamic Crowded Environments with Hierarchical Deep Reinforcement Learning

Tianle Zhang,Zhen Liu,Zhiqiang Pu,Jianqiang Yi,Yanyan Liang,Du Zhang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.7

Although deep reinforcement learning has recently achieved some successes in robot navigation, there are still unsolved problems. Particularly, a robot guided by a distant ultimate goal is easy to get stuck in danger or encounter collisions in dynamic crowded environments due to the lack of long-term perspectives. In this paper, a novel subgoal-guided approach based on two-level hierarchical deep reinforcement learning with spatial-temporal graph attention networks (ST-GANets), called SG-HDRL, is proposed for a robot navigating in a dynamic crowded environment with autonomous obstacles, e.g., crowd. Specifically, the high-level policy, that models the spatialtemporal relation between the robot and the obstacles using the obstacles’ trajectories by the designed high-level ST-GANet, generates intermediate subgoals from a longer-term perspective over higher temporal scales. The subgoals give a favorable and collision-free direction to avoid encountering danger or collisions while approaching the ultimate goal. The low-level policy, that similarly implements the designed low-level ST-GANet to implicitly predict the obstacles’ motions, takes the subgoals as short-term guidance through an intrinsic reward incentive to generate primitive actions for the robot. Simulation results demonstrate that SG-HDRL using ST-GANets has better performances compared with state-of-the-art baselines. Furthermore, the proposed SG-HDRL is deployed to an experimental platform based on omnidirectional cars, and experiment results validate the effectiveness and practicability of the proposed SG-HDRL.

A brain somatic RHEB doublet mutation causes focal cortical dysplasia type II

Shanshan Zhao,Zhenghui Li,Muxian Zhang,Lingliang Zhang,Honghua Zheng,Jinhuan Ning,Yanyan Wang,Feng-Peng Wang,Xiaobin Zhang,Hexia Gan,Yuanqing Wang,Xian Zhang,Hong Luo,Guojun Bu,Huaxi Xu,Yi Yao,Yun-wu 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Focal cortical dysplasia type II (FCDII) is a cerebral cortex malformation characterized by local cortical structure disorganization, neuronal dysmorphology, and refractory epilepsy. Brain somatic mutations in several genes involved in the PI3K/AKT/mTOR pathway are associated with FCDII, but they are only found in a proportion of patients with FCDII. The genetic causes underlying the development FCDII in other patients remain unclear. Here, we carried out whole exome sequencing and targeted sequencing in paired brain–blood DNA from patients with FCDII and identified a brain somatic doublet mutation c.(A104T, C105A) in the Ras homolog, mTORC1 binding (RHEB) gene, which led to the RHEB p.Y35L mutation in one patient with FCDII. This RHEB mutation carrier had a dramatic increase of ribosomal protein S6 phosphorylation, indicating mTOR activation in the region of the brain lesion. The RHEB p.Y35L mutant protein had increased GTPλS-binding activity compared with wild-type RHEB. Overexpression of the RHEB p. Y35L variant in cultured cells also resulted in elevated S6 phosphorylation compared to wild-type RHEB. Importantly, in utero electroporation of the RHEB p.Y35L variant in mice induced S6 phosphorylation, cytomegalic neurons, dysregulated neuron migration, abnormal electroencephalogram, and seizures, all of which are found in patients with FCDII. Rapamycin treatment rescued abnormal electroencephalograms and alleviated seizures in these mice. These results demonstrate that brain somatic mutations in RHEB are also responsible for the pathogenesis of FCDII, indicating that aberrant activation of mTOR signaling is a primary driver and potential drug target for FCDII.

Improvement of Wuyiencin Biosynthesis in Streptomyces wuyiensis CK-15 by Identification of a Key Regulator, WysR

( Yanyan Liu ),( Hojin Ryu ),( Beibei Ge ),( Guohui Pan ),( Lei Sun ),( Kyungseok Park ),( Kecheng Zhang ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.12

Wuyiencin is produced by Streptomyces ahygroscopicus var. wuyiensis CK-15 and is widely used as an antifungal agent in agriculture. Analysis of wuyiencin biosynthetic gene clusters reveals wysR, a member of the LAL-family of transcriptional regulatory genes. WysR consists of an Nterminal PAS domain and a LuxR family C-terminal helix-turn-helix motif. However, the roles of wysR in wuyiencin biosynthesis are largely unknown. In this study, we showed that inactivation of wysR resulted in the complete loss of wuyiencin production, which could be restored by complementation with a single copy of wysR. Furthermore, we successfully increased wuyiencin production to a significantly higher level by overexpression of wysR in S. wuyiensis CK-15. Quantitative real-time RT-PCR analysis showed that WysR regulates wuyiencin biosynthesis by modulating other putative regulatory genes. Thus, WysR was identified as an activator of wuyiencin biosynthesis, and overexpression of wysR gene proved to be an effective strategy for improving wuyiencin production.