Broad-specificity amino acid racemase, a novel non-antibiotic selectable marker for transgenic plants

Yi‑Chia Kuan,Venkatesan Thiruvengadam,Jia‑Shin Lin,Jia‑Hsin Liu,Tsan‑Jan Chen,Hsin‑Mao Wu,Wen‑Ching Wang,Liang‑Jwu Chen 한국식물생명공학회 2018 Plant biotechnology reports Vol.12 No.1

The broad-specificity amino acid racemase (Bsar) from Pseudomonas putida catalyzes the racemization of various amino acids, offering a flexible and feasible platform to develop a new non-antibiotic selectable marker system for plant transformation. In the present study, we demonstrated that a Bsar variant, Bsar-R174K, that is useful as a selectable marker gene in Arabidopsis and rice that were susceptible to l-lysine and D-alanine. The introduction of wild-type Bsar, Bsar-R174K or Bsar-R174A into E. coli lysine or asparagine auxotrophs was able to rescue the growth of these microorganisms in minimal media supplemented with selectable amino acid enantiomers. The transformation of Arabidopsis with Bsar or Bsar variants based on d-alanine selection revealed that Bsar-R174K had the greatest efficiency (2.40%), superior to kanamycin selectionbased transformation (1.10%). Whereas, l-lysine-based selection exhibited lower efficiency for Bsar-R174K (0.17%). The progenies of selected Bsar-R174K transgenic Arabidopsis revealed normal growth properties. In addition, Bsar-R174K transgenic rice was obtained on l-lysine medium with an efficiency of 0.9%, and the progenies of the transgenic rice revealed morphologically normal phenotypes comparable with their wild-type counterparts. This study presents the first report of broad range amino acid racemase Bsar-R174K as a non-antibiotic selectable marker system applied in transgenic plants.

Fresh Washed Microbiota Transplantation Alters Gut Microbiota Metabolites to Ameliorate Sleeping Disorder Symptom of Autistic Children

Liu Nai-Hua,Liu Hong-Qian,Zheng Jia-Yi,Zhu Meng-Lu,Wu Li-Hao,Pan Hua-Feng,He Xing-Xiang 한국미생물학회 2023 The journal of microbiology Vol.61 No.8

Accumulating studies have raised concerns about gut dysbiosis associating autism spectrum disorder (ASD) and its related symptoms. However, the effect of gut microbiota modification on the Chinese ASD population and its underlying mechanism were still elusive. Herein, we enrolled 24 ASD children to perform the first course of fresh washed microbiota transplantation (WMT), 18 patients decided to participate the second course, 13 of which stayed to participate the third course, and there were 8 patients at the fourth course. Then we evaluated the effects of fresh WMT on these patients and their related symptoms. Our results found that the sleeping disorder symptom was positively interrelated to ASD, fresh WMT significantly alleviated ASD and its sleeping disorder and constipation symptoms. In addition, WMT stably and continuously downregulated Bacteroides/ Flavonifractor/Parasutterella while upregulated Prevotella_9 to decrease toxic metabolic production and improve detoxification by regulating glycolysis/myo-inositol/D-glucuronide/D-glucarate degradation, L-1,2-propanediol degradation, fatty acid β-oxidation. Thus, our results suggested that fresh WMT moderated gut microbiome to improve the behavioral and sleeping disorder symptoms of ASD via decrease toxic metabolic production and improve detoxification. Which thus provides a promising gut ecological strategy for ASD children and its related symptoms treatments.

A Multifactorial Corpus Analysis on Preferred English Prenominal Adjective Order

LIU YI 한국언어연구학회 2016 언어학연구 Vol.21 No.3

This study aims to find out whether British English (BrE) and American English (AmE) have different preferences over prenominal adjective order (AO) in terms of the influential factors. According to the literature, seven factors are reported to be influential in governing English prenominal adjective order (AO). These factors include: syntactic, semantic, phonological and psychological aspects. The purpose of this study is to examine whether British English (BrE) and American English (AmE) have different preferences in regard to prenominal AO in terms of the influential factors. A multifactorial methodology was adopted to investigate native speakers' AO choices via computing a regression model by computer R language. It was found that there were more similarities than differences between BrE and AmE in their preference over AO, and the factor of IndComp is reported to significantly influence only AmE but not BrE. The factors of Length, AffLoad and Freq are positively influencing both BrE and AmE on prenominal AO, which is in accordance with the literature. Howver, the factors of SemClose and SegAlt had negative influences which was inconsistent with the literature. Further, the factor of NomChar is reported to have influence on neither BrE nor AmE.

Study of a Magnetic Switch for the SG-III Energy Module

Liu Gang,Lin Fuchang,Liu Yi,Li Hua,Lee Li,Zeng Han 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.61

The SG-III energy module, which supplies pumping energy for Xenon (Xe) flashlamps, is one of the most important modules in large laser facilities. A two-electrode spark gap switch is used as the main discharge switch and is triggered by a Marx generator. The peak value of the output impulse generated by the Marx generator is about 180 kV, and its rise time is about 10 ns. In order to prevent the key elements (e.g., Xe flashlamps) from being damaged by the trigger impulse, a magnetic switch is used to isolate the high-voltage impulse. The design, working principle and performance of a magnetic switch based on Fe-based nanocrystals are presented in this paper. Compared with the magnetic switch employed in magnetic pulse compressors (MPCs), the magnetic switch in SGIII works under a single nanosecond impulse. It corresponds to the initial magnetization curve of the B-H curve. The parameters of the Fe-based nanocrystals are obtained by experiments. The unsaturated inductance, saturated inductance and saturation time are the key parameters of the magnetic switch in SG-III and are considered in the design. Finally, the experimental results for the magnetic switch in SG-III are presented.

Human April

Liu Yi Cheng 한국콘텐츠학회 2022 ICCC International Digital Design Invitation Exhib Vol.2022 No.07

Control Design of the Brushless Doubly-Fed Machines for Stand-Alone VSCF Ship Shaft Generator Systems

Liu, Yi,Ai, Wu,Chen, Bing,Chen, Ke The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

This paper presents a stand-alone variable speed constant frequency (VSCF) ship shaft generator system based on a brushless doubly-fed machine (BDFM). In this system, the output voltage amplitude and frequency of the BDFM are kept constant under a variable rotor speed and load by utilizing a well-designed current vector controller to regulate the control winding (CW) current. The control scheme is proposed, and the hardware design for the control system is developed. The proposed generator system is tested on a 325 TEU container vessel, and the test results show the good dynamic performance of the CW current vector controller and the whole control system. A harmonic analysis of the output voltage and a fuel consumption analysis of the generator system are also implemented. Finally, the total efficiency of the generator system is presented under different rotor speeds and load conditions.

A Corpus-based Study on the Use of English Present Perfect by Chinese EFL Learners

( Liu Yi ) 대한언어학회 2016 언어학 Vol.24 No.2

Through the comparison of the corpora of LOCNESS and CLEC, this study examines Chinese EFL learners’ unique features in using English present perfect. It shows that Chinese learners are more obsessed with using resultative perfect compared with native speakers (p<.05). And Chinese learners use more experiential perfect along with their rising English proficiency, and there is a huge gap between different proficient learners (p<.05). With respect to persistent and recent perfect, both native and non-native speakers marginally used them. Chinese learners’ performance may be influenced by many factors such as L1/L2 interference, typicality of target language, learners’ different English proficiency, and learners’ avoidance of using target language, and so on. This study hopes to provide some implications to the EFL teaching.

중국의 정부개혁 구조

Yi - Chang Liu 한국행정학회 1995 한국행정학회 학술발표논문집 Vol.1995 No.-

Elastography for Breast Cancer Diagnosis: a Useful Tool for Small and BI-RADS 4 Lesions

Liu, Xue-Jing,Zhu, Ying,Liu, Pei-Fang,Xu, Yi-Lin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.24

The present study aimed at evaluating and comparing the diagnostic performance of B-mode ultrasound (US), elastography score (ES), and strain ratio (SR) for the differentiation of breast lesions. This retrospective study enrolled 431 lesions from 417 in-hospital patients. All patients were examined with both conventional ultrasound and elastography. Two experienced radiologists reviewed ultrasound and elasticity images. The histopathologic result obtained from ultrasound-guided core biopsy or operation excisions were used as the reference standard. Pathologic examination revealed 276 malignant lesions (64%) and 155 benign lesions (36%). A cut-off point of 4.15 (area under the curve, 0.891) allowed significant differentiation of malignant and benign lesions. ROC (receiver-operating characteristic) curves showed a higher value for combination of B-mode ultrasound and elastography for the diagnosis of breast lesions. Conventional ultrasound combined elastography showed high sensitivity, specificity, and accuracy for group II lesions (10mm<lesion diameter ${\leq}20mm$). Elastography combined with conventional ultrasound show high specificity and accuracy for differentiation of benign and malignant breast lesions. Elastography is particularly important for the diagnosis of BI-RADS 4 and small breast lesions.

Performance Analysis of a Stand-alone Brushless Doubly-fed Induction Generator Using a New T-type Steady-state Model

Liu, Yi,Xu, Wei,Zhi, Gang,Zhang, Junlin The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.4

The brushless doubly-fed induction generator (BDFIG) is a new type of dual stator winding induction generator. In such a generator, both the power winding (PW) and the control winding (CW) are housed in the stator. This paper presents the performance characteristics of a stand-alone BDFIG operation system. A new T-type steady-state model of a BDFIG is proposed. This model is more suitable for the performance analysis of stand-alone BDFIGs than the conventional Π-type steady-state model and the simplified inner core steady-state model. The characteristics of the power flow and CW current are analyzed by detailed mathematical derivations on the basis of the proposed T-type steady-state model. The analysis results are verified by experiments, which are carried out on a prototype BDFIG. The results of the performance analysis contribute to simplifying the control circuit, improving the control performance, and selecting an appropriate BDFIG for actual industrial applications.