CHARACTERIZATION AND MORPHOLOGY CONTROL OF POLY(p-PHENYLENEDIAMINE) MICROSTRUCTURES IN DIFFERENT pH

SI-WEI YANG,FANG LIAO 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2011 NANO Vol.6 No.6

A novel and shape-controlled synthesis method for uniformly-shaped poly(p-phenylenediamine)(PpPD) microparticles was developed using (NH_4)_2S_2O_8 (APS) as an oxidant. The results demonstrated that the morphologies of PpPD varied from nanofibers to nanospheres and nestlike microspheres by tuning the pH of solution. Tiny pH change leads to the significant change in product morphology. The structure of microspheres is similar to graphene which was first discovered. Further study showed that the PpPD nanofibers were dimer. The difference in the structure of PpPD nanofibers and nanospheres (microspheres) resulted in different solubility in water. The nanosized oligomer crystallites served as starting templates for the nucleation of PpPD nanofibers. Further growth of nanofibers was proceeded by the self-organization of phenazine units or their blocks located at the ends of the PpPD chains.

노을공원 쓰레기매립지 식생복원을 위한 아까시나무 천이방향 연구

위사양 ( Wei Si-yang ),오충현 ( Oh Choong-hyeon ) 한국환경복원기술학회(구 한국환경복원녹화기술학회) 2021 한국환경복원기술학회지 Vol.24 No.3

The waste landfill that has been used as a park through a stabilization project to provide green space to local residents. Vegetation restoration is necessary for the landfill park project, but it is difficult to restore vegetation due to various disturbances in the landfill. This study analyzed the successional dynamics and ecological characteristics of Robinia pseudoacacia communities from the slopes of Noeul Park by applying the 7-stage successional hypothesis. As a result of the study, there was almost no intermediate successional stage. There are only the early successional stage which Robinia pseudoacacia has an absolute dominance of 100% in the crown and middle layers, and the degeneration successional stage which formed by the introduction of Morus alba. This result showed that the succession of Robinia pseudoacacia communities were not able to proceed to the climax forest due to various disturbances in the waste landfill. Therefore, it was analyzed that it is necessary to induce the succession through intermediate steps such as Morus alba , since it is difficult to transition from Robinia pseudoacacia community to the native Quercus spp. community.

한중 생태계서비스지불제도 비교 연구: 참여주체와 지불조건 및 지불기준 중심으로

위사양 ( Si-yang Wei ),오충현 ( Choong-hyeon Oh ) 한국환경생태학회 2021 한국환경생태학회 학술대회지 Vol.2021 No.2

2020년부터 전 세계적으로 기승을 부리고 있는 covid-19, 2021년 전 세계적인 극단기후와 자연재해는 인류사회가 하나의 공동체이고 모든 국가가 지구라는 생태계 안에 존재한다는 것을 잘 보여주고 있다. 또한 전 지구적 생태계 문제는 지리적·정치적 경계를 초월하여 협력을 통해 해결하는 것이 필요하다. 지리적으로 뿐만 아니라 경제, 문화 분야에서도 긴밀히 인접하고 있는 한중 양국은 동북아시아에서 영향력이 가장 큰 국가이다. 따라서 생태환경 보전 및 환경문제 해결에 대한 양국의 교류 및 협력은 매우 중요하다. 생태계서비스지불제도는 산업개발과 생태환경보호간의 모순을 완화 또는 해결하는 주요 수단으로 생태학, 경제학, 사회학, 경영학 등 여러 분야의 학문을 교차하는 연구이다. 문화적 기반이 같으면서도 역사적으로 정치와 경제 체계가 서로 다른 한중 양국 간 생태계보전 관련 제도를 연구하고, 생태계 보전정책 경험을 종합해 서로 참고하면 양국 생태계 보전제도 발전에 큰 도움이 될 것으로 기대된다. 또한 비교분석을 통해 양국 제도의 공통점과 차이점을 파악하고 양국간 생태보상제도 연구와 협력방향을 모색할 경우 향후 동북아 지역에서 보다 심도 깊은 생태환경보전 협력사업을 진행할 수 있다. 본 연구는 한국의 생태계서비스지불제도와 이와 유사한 중국의 생태보상제도를 비교 대상으로 하여 문헌조사를 통해 참여자, 지급조건과 기준, 지급방식, 예산확보 방식 및 사업성과 평가 등의 구성요소를 비교하고 제도 시행 사례를 종합하여 양국 생태보상제도 구성요소의 특성을 파악하였다. 한중 생태계서비스지불제도 참여 주체를 비교한 결과,양국 생태계서비스지불제도 사업은 지불주체-보상주체로 유형이 구분된다. 그 유형은 공-공, 공-사, 사-공, 그리고 사-사 유형이다. 중국은 특별하게 공적주체만 참여하는 공-공 유형이 있으며 이는 생태보상제도의 중요한 부분이기도 하다. 한국의 정치체계는 중국과 다르지만 생태계서비스지불제도 시행에 중앙정부 또는 관련부서가 사업 전반적인 계획 및 행정적 지원을 시행하는 것은 중국과 유사하다. 한중 생태계서비스지불제도 지불조건 및 지불기준을 비교한 결과는 다음과 같다. 지불조건의 경우, 중국의 생태보상은 생태계 보전뿐 아니라 생태계서비스가 공급되는 지역의 주민 생활 수준 향상, 생태보전 우선지역과 경제개발 우선지역의 발전적 균형을 조율하는 목표를 가지고 있다. 따라서 생태보상을 지불할 때는 생태보전사업과 활동이 실제로 진행되었을 때 투입되는 보상뿐만 아니라 지역주민들이 생태보전을 위해 발전을 포기함으로 인해 발생하는 발전기회 손실에 대한 보상도 시행한다. 즉 중국의 생태보상 지불조건은 '작위'와 '부작위'가 모두 인정되어 보상되는 원칙이다. 반면 한국은 실제 진행되는 생태계 서비스 보전·증진 활동의 '작위'만 인정하고 이를 보상하고 있다. 지불기준의 경우 중국의 생태보상 사업은 대규모 토지와 참여자 다수가 포함되는 경우가 많아 행정원가를 줄이기 위해 정부가 직접 지불기준을 정하는 방식을 사용하고 있다. 반면 한국은 지불대상 지역이나 지불대상자의 특성에 따라 차등화된 지급기준을 적용하고 있다.

Performance comparisons of two biomarker-based panels for early diagnosis of hepatocellular carcinoma in nonalcoholic fatty liver disease: A multi-institutional case-control analysis

Wei OUYANG,Ming-Cheng GUAN,Si-Yu LIU,Xin-Fei XU,Li-Yang SUN,Ming-Da WANG,Feng SHEN,Xiang-Min TONG,Hong ZHU,Tian YANG 한국간담췌외과학회 2022 Annals of hepato-biliary-pancreatic surgery Vol.26 No.-

Thiazinogeldanamycin, a New Geldanamycin Derivative Produced by Streptomyces hygroscopicus 17997

( Si Yang Ni ),( Lin Zhuan Wu ),( Hong Yuan Wang ),( Mao Luo Gan ),( Yu Cheng Wang ),( Wei Qing He ),( Yi Guang Wang ) 한국미생물 · 생명공학회 2011 Journal of microbiology and biotechnology Vol.21 No.6

A new geldanamycin (GDM) derivative was discovered and isolated from the fermentation broth of Streptomyces hygroscopicus 17997. Its chemical structure was elucidated as thiazinogeldanamycin by LC-MS, sulfur analysis, and NMR. The addition of cysteine to the fermentation medium significantly stimulated the production level of thiazinogeldanamycin, suggesting cysteine as a precursor of thiazinogeldanamycin production. Although showing a decreased cytotoxicity against HepG2 cancer cells, thiazinogeldanamycin exhibited an improved water solubility and photostability. Thiazinogeldanamycin may represent the first natural GDM derivative characterized so far that uses GDM as its precursor. Its appearance also clearly indicates that an appropriate end-point of fermentation is of critical importance for the maximal production of GDM by Streptomyces hygroscopicus 17997.

Polymorphisms in TYMS for Prediction of Capecitabine-Induced Hand-Foot Syndrome in Chinese Patients with Colorectal Cancer

Si-Qi Dong,Tong-Min Wang,Jiang-Bo Zhang,Yong-Qiao He,Wen-Qiong Xue,Zi-Yi Wu,Da-Wei Yang,Lian-Jing Cao,Jing-Wen Huang,Xi-Zhao Li,Pei-Fen Zhang,Xiao-Hui Zheng,Wei-Hua Jia 대한암학회 2021 Cancer Research and Treatment Vol.53 No.3

Purpose Capecitabine is an extensively used oral prodrug of 5-fluorouracil in treatment of colon cancer and is known to cause hand-foot syndrome (HFS). As the target enzyme for capecitabine, thymidylate synthase (TYMS) plays a key role for 5-fluorouracil metabolism and has been associated with some side effects caused by capecitabine. The aim of our study is to identify the possible genetic predictors of capecitabine-induced HFS (CAP-HFS) in Chinese colorectal cancer patients.Materials and Methods Whole exons of TYMS were sequenced for 288 extreme phenotype HFS patients, including 144 severe or early-onset (first 2 cycles) moderate HFS extreme cases and 144 extreme controls with no reported HFS. The associations between polymorphisms and CAP-HFS were analyzed using logistic regression under an additive model.Results We identified a novel risk mutation (c.1A>G, chr18:657743), was associated with severe HFS in an extreme case who was affected during the first cycle of treatment. Moreover, we identified three new variants, rs3786362, rs699517, rs2790, and two previously reported variants, 5’VNTR 2R/3R and 3′-untranslated region 6-bp ins-del, which were significantly associated with CAP-HFS (p < 0.05). In silico analysis revealed that the effect of these polymorphisms in the TYMS region on the development of HFS might not be restricted solely to the regulation of TYMS expression, but also the TYMS catalytic activity through the indirect effect on ENOSF1 expression.Conclusion This study identified new polymorphisms in TYMS gene significantly associated with CAP-HFS, which may serve as useful genetic predictors for CAP-HFS and help to elucidate the underlying mechanism of HFS.

Prevalence and Genetic Characterization of Toxoplasma gondii in House Sparrows (Passer domesticus) in Lanzhou, China

Wei Cong,Si-Yang Huang,Dong-Hui Zhou,Xiao-Xuan Zhang,Nian-Zhang Zhang,Quan Zhao,Xing-Quan Zhu 대한기생충학열대의학회 2013 The Korean Journal of Parasitology Vol.51 No.3

Daclatasvir plus Asunaprevir in Interferon (± Ribavirin)- Ineligible/Intolerant Asian Patients with Chronic HCV Genotype-1b Infection

( Lai Wei ),( Mingxiang Zhang ),( Min Xu ),( Wan-Long Chuang ),( Wei Lu ),( Wen Xie ),( Zhansheng Jia ),( Guozhong Gong ),( Yueqi Li ),( Si Hyun Bae ),( Yong-Feng Yang ),( Qing Xie ),( Shumei Lin ),( 대한간학회 2016 춘·추계 학술대회 (KASL) Vol.2016 No.1

Aims: The efficacy/safety of daclatasvir (pan-genotypic NS5A inhibitor) plus asunaprevir (NS3 protease inhibitor) in interferon (± ribavirin)- ineligible/intolerant patients with chronic HCV genotype-1b infection from mainland China, Korea and Taiwan was investigated in a phase 3, open-label study. Methods: Patients received daclatasvir 60 mg (tablet) once daily plus asunaprevir 100 mg (soft capsule) twice daily for 24 weeks. The primary endpoint was sustained virologic response at post-treatment Week 24 (SVR24). Results: This study treated 159 patients from mainland China (80%), Korea (11%) and Taiwan (9%), including patients with cirrhosis (33%), IL28B non-CC genotypes (40%), and aged ≥70 years (4%). SVR24 was achieved by 91% of patients (100% concordance with SVR12) and was similarly high in all subgroups, e.g. cirrhotic patients (90%), and in patients from mainland China (91%), Korea (94%) and Taiwan (87%). SVR24 was higher in patients without baseline NS5A (L31M/Y93H) resistance-associated variants (RAVs) (n=137/139 [99%]), regardless of the presence (98%) or absence (99%) of cirrhosis, and lower in patients with baseline NS5A RAVs (n=8/19 [42%]). All serious adverse events (AEs) (n=5/159 [3.1%]), grade 4 laboratory abnormalities (n=3/159 [1.9%]) and deaths (n=1/159 [0.6%]) that occurred on-treatment were unrelated to the study drugs; two patients discontinued due to AEs. Treatment was generally well tolerated regardless of cirrhosis status. Conclusions: Daclatasvir plus asunaprevir achieved a high SVR24 rate of 91%, rising to 99% in patients without baseline NS5A RAVs, and was generally well tolerated in cirrhotic and non-cirrhotic interferon (± ribavirin)-ineligible/intolerant patients with HCV genotype-1b infection from mainland China, Korea and Taiwan.

Effects of dietary Enteromorpha powder on reproduction-related hormones and genes during the late laying period of Zi geese

Ma Wei Qing,Zhao Dan Hua,Cheng Huang Zuo,Wang Si Bo,Yang Ji,Hong Xia Cui,Lu Ming Yuan,Wu Hong Zhi,Xu Li,Liu Guo Jun 아세아·태평양축산학회 2021 Animal Bioscience Vol.34 No.3

Objective: The aim of this study was to investigate the effects of Enteromorpha powder supplementation on reproduction-related hormones and genes in the late laying period of Zi geese. Methods: A total of 312 (1-year-old) Zi geese with similar laying rate were randomly divided into 2 groups with 6 replicates each, each with 21 female geese and 5 male geese. The control group was fed with a basal diet and the test group was fed with a diet containing 3% Enteromorpha powder. The trial period lasted for 7 weeks. Results: Our results showed that the laying rate was improved in the test group at each week of trial (p<0.01), and the levels of estradiol in serum and prolactin in ovary were increased compared with the control group (p<0.05). Conclusion: Based on above results, Enteromorpha powder supplementation at 3% could promote reproductive performance during the late laying period of Zi geese. Objective: The aim of this study was to investigate the effects of Enteromorpha powder supplementation on reproduction-related hormones and genes in the late laying period of Zi geese.Methods: A total of 312 (1-year-old) Zi geese with similar laying rate were randomly divided into 2 groups with 6 replicates each, each with 21 female geese and 5 male geese. The control group was fed with a basal diet and the test group was fed with a diet containing 3% <i>Enteromorpha</i> powder. The trial period lasted for 7 weeks.Results: Our results showed that the laying rate was improved in the test group at each week of trial (p<0.01), and the levels of estradiol in serum and prolactin in ovary were increased compared with the control group (p<0.05).Conclusion: Based on above results, <i>Enteromorpha</i> powder supplementation at 3% could promote reproductive performance during the late laying period of Zi geese.

The impacts of day trading activity on market quality: evidence from the policy change on the Taiwan stock market

( Tun-ya Yang ),( Si-yuan Huang ),( Wei-che Tsai ),( Pei-shih Weng ) 한국파생상품학회(구 한국선물학회) 2020 선물연구 Vol.28 No.4

This paper aims to investigate the impact of day trading on market quality on the Taiwan stock market with the implementation of a unique policy change. This paper examines 396 listed stocks from June 2015 to October 2016, a period when the stock market in Taiwan officially approved selected stocks for day trading for all investors. Within the sample period, the empirical findings show that day trading increases the bid-ask spread, price depth and stock volatility, indicating that day trading activities not only cause higher transaction costs and trading risk but also raise the market’s ability to absorb price impact. This paper considers two-stage regression and tests the exogenous shock because of further relaxation for day trading to deal with the possible endogenous problem and the main findings remain consistent. Since early 2014, the Taiwan stock market has been experiencing a distinct growth in trading volume after unwinding the day trading; however, the results show that the impacts of stock day trading on market quality are not all positive.