Tea consumption is associated with a reduced risk of coronary heart disease in female but not male populations in Guangzhou, China

Chen, Ying,Ye, Yanfang,Zhang, Zhen,Zhang, Chi,Chen, Minyu,Pang, Jun,Zhou, Shuxian,Xiang, Qiuling The Korean Nutrition Society 2019 Nutrition Research and Practice Vol.13 No.5

BACKGROUND/OBJECTIVES: The association between tea consumption and risk of coronary heart disease (CHD) remains controversial. This study aimed to determine whether tea consumption has an effect on CHD risk in Chinese adults. SUBJECTS/METHODS: In this hospital-based case-control study, 267 cases of CHD and 235 non-CHD controls were enrolled. Blood samples from all cases were examined. Cardiac function indices (left ventricular ejection fraction, left ventricular end-diastolic dimension, lactate dehydrogenase, and creatine kinase of the muscle or brain type), blood lipid index (high-density lipoprotein cholesterol), and blood coagulation function indices (fibrinogen and activated partial thromboplastin time) were recorded. Tea consumption of study participants was assessed by a specifically designed questionnaire. The baseline characteristics of the study populations were recorded, and CHD-related biomarkers were detected. Differences in baseline characteristics of the study participants were examined using t-tests for continuous variables and chi-squared tests for categorical variables. Unconditional logistic regression was used to measure the association between tea and CHD. RESULTS: There were significant differences in cardiac function indices, blood lipid index, and blood coagulation indices between CHD cases and controls (P < 0.05). We found tea consumption reduced CHD risk in female participants (adjusted odds ratio (OR) = 0.484, 95% CI: 0.242-0.968, P = 0.0403). Regarding the type of tea consumed, the risk of CHD was reduced in women who drank partially fermented tea (adjusted OR = 0.210, 95% CI: 0.084-0.522, P = 0.0008). Analytic results for the amount of tea consumed per unit time showed CHD risk was reduced in women who consumed 1-2 cups of tea per day (adjusted OR = 0.291, 95% CI: 0.131-0.643, P = 0.0023). A tea-drinking frequency of > 6 days/week was beneficial for CHD prevention (adjusted OR = 0.183, 95% CI: 0.049-0.679, P = 0.0112). When analyzed according to the duration of tea consumption, the risk of CHD was reduced in participants who had been drinking tea for 10-20 years (adjusted OR = 0.360, 95% CI: 0.137-0.946, P = 0.0382). CONCLUSIONS: Tea consumption is associated with a reduced risk of CHD in female but not male populations in Guangzhou.

A pilot-scale test on the treatment of biological pretreated leachate by the synergy of ozonation-biological treatment-catalytic ozonation

Yuanmei Chen,Yutang Xiao,Guanping Wang,Wei Shi,Linquan Sun,Yanfang Chen,Aichun Miao 대한환경공학회 2021 Environmental Engineering Research Vol.26 No.4

In this pilot-scale test, the ozonation-biological treatment-catalytic ozonation system was performed to treat complex organics and highly-concentrated total nitrogen (TN) in biological pretreated incineration leachate. The test results showed that the ratio of five-day biochemical oxygen demand (BOD5) / chemical oxygen demand (COD) increased from 0.059 to 0.237, which indicated that the concentration of biodegradable COD (CODbio) increased by ozonation pre-treatment process. In addition, the TN removal mainly occurred in anaerobic zone due to direct denitrification by the activated bacteria, which were domesticated through different influent ratio. Moreover, it was necessary to add catalytic ozonation process to reach higher direct effluent discharge criteria. After 60 days repeated debugging, the removal rate of COD and TN reached 88.5% and 98.2%, respectively. Finally, the total cost of this system was ￥ 6.65 /㎥ ($ 0.95 /㎥), which was acceptable for the treatment of biological pretreated leachate. This pilot-scale test could provide some guiding information for the treatment of leachate containing highly-concentrated TN with low CODbio/N by the composite system.

Tea consumption is associated with a reduced risk of coronary heart disease in female but not male populations in Guangzhou, China

Ying Chen,Yanfang Ye,Zhen Zhang,Chi Zhang,Minyu Chen,Jun Pang,Shuxian Zhou,Qiuling Xiang 한국영양학회 2019 Nutrition Research and Practice Vol.13 No.5

BACKGROUND/OBJECTIVES: The association between tea consumption and risk of coronary heart disease (CHD) remains controversial. This study aimed to determine whether tea consumption has an effect on CHD risk in Chinese adults. SUBJECTS/METHODS: In this hospital-based case-control study, 267 cases of CHD and 235 non-CHD controls were enrolled. Blood samples from all cases were examined. Cardiac function indices (left ventricular ejection fraction, left ventricular end-diastolic dimension, lactate dehydrogenase, and creatine kinase of the muscle or brain type), blood lipid index (high-density lipoprotein cholesterol), and blood coagulation function indices (fibrinogen and activated partial thromboplastin time) were recorded. Tea consumption of study participants was assessed by a specifically designed questionnaire. The baseline characteristics of the study populations were recorded, and CHD-related biomarkers were detected. Differences in baseline characteristics of the study participants were examined using t-tests for continuous variables and chi-squared tests for categorical variables. Unconditional logistic regression was used to measure the association between tea and CHD. RESULTS: There were significant differences in cardiac function indices, blood lipid index, and blood coagulation indices between CHD cases and controls (P < 0.05). We found tea consumption reduced CHD risk in female participants (adjusted odds ratio (OR) = 0.484, 95% CI: 0.242-0.968, P = 0.0403). Regarding the type of tea consumed, the risk of CHD was reduced in women who drank partially fermented tea (adjusted OR = 0.210, 95% CI: 0.084-0.522, P = 0.0008). Analytic results for the amount of tea consumed per unit time showed CHD risk was reduced in women who consumed 1-2 cups of tea per day (adjusted OR = 0.291, 95% CI: 0.131-0.643, P = 0.0023). A tea-drinking frequency of > 6 days/week was beneficial for CHD prevention (adjusted OR = 0.183, 95% CI: 0.049-0.679, P = 0.0112). When analyzed according to the duration of tea consumption, the risk of CHD was reduced in participants who had been drinking tea for 10-20 years (adjusted OR = 0.360, 95% CI: 0.137-0.946, P = 0.0382). CONCLUSIONS: Tea consumption is associated with a reduced risk of CHD in female but not male populations in Guangzhou.

Numerical analysis of thermal dynamics and mixing performance in the blade-type static mixers

Yanfang Yu,Yaxin Chen,Huibo Meng,Yunjuan Yao,Dongzhou Liu,Jianhua Wu 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.7

The turbulent thermal dynamics and mixing performance of kenics static mixer (KSM), lightnin static mixer (LSM) and Q-type static mixer (QSM) were numerically simulated with uniform heat flux within the range of Reynolds numbers (Re) between 6000 and 30000. The numerical predictions of Nusselt number (Nu) and friction coefficient (f) in KSM were well consistent with the experimental data. The dean vortices, thermal resistance, entropy generation and field synergy were fully analyzed to obtain the enhancement mechanism of heat transfer performance. The synergy performance between temperature gradient and flow field firstly decreased and then increased and are superior to that of KSM with increasing Re. With the same Re, the entropy generation rates of LSM are 0.93-0.94 times that of QSM. LSM is a better alternative consideration for convection mixing and heat transfer enhancement. Two new relationships between Nu and f under different dimensionless uniform heat flux are obtained.

Rolling window 기법 적용을 통한 도심 지역 장기측정 결과의 오염원 규명 연구

권수진,Yanfang Chen,윤종철,김화진 한국대기환경학회 2022 한국대기환경학회 학술대회논문집 Vol.2022 No.10

Multi-Dimensional CFD Analysis for the Prediction of Transient Wellbore Circulating Temperature Profile to Guide Offshore Cementing Job

Ran Wang,Yanfang Wang,Mayank Tyagi,Yuanhang Chen,Seung Ihl Kam 한국자원공학회 2019 한국자원공학회지 Vol.56 No.4

This study investigates how temperature profile changes with time during fluid circulation through the wellbore and annulus by using ANSYS Fluent, to help designing offshore cementing job in the petroleum industry. The use of two-dimensional nature of transient computational-fluid-dynamics (CFD) simulations shows that both flow rheology and fluid distribution in the well affect heat transfer calculations and such an effect is more pronounced at the bottom hole where the flow direction changes from downward to upward. When compared with one-dimensional (1D) simulation, multi-dimensional simulation results predict a longer time for heat transfer consistently, implying that simple 1D simulation techniques tend to under-predict the amount of time associated with cementing job. How fluid distribution within the well changes with time and how the resulting pressure and temperature calculations are affected at different times and locations are also visualized in this study.

서울 상공(615 m)에서의 PM<SUB>2.5</SUB> 특성연구: 지표 입자 특성과의 비교 및 혼합고 영향 중심으로

권수진,백경민,Yanfang Chen,박유진,전지원,신윤미,박창호,유승성,김화진 한국대기환경학회 2021 한국대기환경학회 학술대회논문집 Vol.2021 No.10

대기 중 입자 농도 및 특성의 일변화에 있어서 기상요소가 중요하며, 특히 혼합고(planetary boundary layer, PBL)의 영향은 크게 영향을 미친다. 대기 혼합고는 일반적으로 온도가 비교적 낮은 밤에는 얕으며, 온도가 높은 낮 시간에는 대기 혼합고가 상승하여 혼합층 내부의 활발한 대류가 일어난다. 이러한 대기 혼합고의 변동에 따라 PM 농도 및 화학조성은 영향을 받으며, 이를 분석함으로써, 에어로졸 확산과 외부로부터의 유입에 대해 파악할 수 있다. 본 연구에서는 혼합고의 변화가 미세먼지 농도 및 특성변화에 미치는 특성을 파악하기 위하여 지표 측정 지점인 KIST에서 Aerodyne Aerosol Mass Spectrometer (AMS)를, 상공 측정 지점(>600 m)으로는 관악산을 선정하여 Aerosol Chemical Speciation Monitor (ACSM)를 각각 설치, 이용하여 실시간 측정 및 분석을 진행하였다. 고도에 따른 대기 관측에 앞서 두 기기 간의 aerodynamic lens와 vaporizer 등에서 오는 관측오차를 확인하기 위하여 validation을 진행하였다. Capture vaporizer가 적용된 ACSM의 cyclone inlet 조건만 변경하여 AMS와 동시에 가동하여 비교분석을 진행하였다. 이후 ACSM를 이용하여 상공(관악산)에서의 미세먼지 농도, 일변화, 화학적 특성을 실시간으로 측정하여 지표(KIST)의 AMS와 비교하였다. 이를 통하여 본 연구에서는 대기관측을 진행한 겨울 기간 동안 관악산의 해발고도를 기준으로 대기 혼합고의 변동에 따라 지상 데이터와 비교하여, 1) 상공 미세먼지의 특성 2) 고농도 발생 시 장거리 이동 영향 3) 혼합고가 도심 미세먼지 특성에 미치는 영향 등에 대하여 논하고자 한다.

Association Between Excessive Daytime Sleepiness and Functional Gastrointestinal Disorders: A Population-based Study in China

( Sicheng Wu ),( Shuqi Chen ),( Yanfang Zhao ),( Xiuqiang Ma ),( Rui Wang ),( Jia He ) 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2017 Journal of Neurogastroenterology and Motility (JNM Vol.23 No.2

Background/Aims Several studies have demonstrated that sleep problems are associated with functional gastrointestinal disorders (FGIDs): irritable bowel syndrome (IBS), functional dyspepsia, etc, but the relationship between excessive daytime sleepiness (EDS) and FGIDs has not been systematically studied in the general population. This study aims to explore the relationship between EDS and specific types of FGIDs and the effect of the number of FGIDs on EDS. Methods A sample of 3600 individuals (aged 18-80 years) was selected from 5 regions in China using a randomized, stratified, multi-stage sampling method. EDS was measured by the Epworth Sleepiness Scale, while gastroesophageal reflux disease (GERD) and other FGIDs were assessed by Reflux Disease Questionnaire and the Rome II diagnostic criteria, respectively. Results The survey was completed by 2906 individuals (response rate: 80.72%), and 644 individuals (22.16%) had EDS. EDS was significantly associated with ulcer-like dyspepsia (OR, 2.50; 95% CI, 1.08-5.79), diarrhea-predominant IBS (OR, 2.00; 95% CI, 1.09-3.66), alternating IBS (OR, 2.32; 95% CI, 1.30-4.13), functional constipation (OR, 1.68; 95% CI, 1.20-2.35), and GERD (OR, 1.72; 95% CI, 1.08-2.72). Risk of EDS increased along with the increasing numbers of FGIDs: with 1 FGID (OR, 1.72; 95% CI, 1.37-2.15); with 2 FGIDs (OR, 2.43; 95% CI, 1.63-3.62); and with 3 or more FGIDs (OR, 3.26; 95% CI, 1.37-7.78). Conclusions FGIDs, such as ulcer-like dyspepsia, diarrhea-predominant IBS, alternating IBS, functional constipation, and GERD, were significantly associated with EDS. Those who suffered from more kinds of FGIDs were more susceptible to EDS. (J Neurogastroenterol Motil 2017;23:298-305)

Characterization of Dilution Chamber System for Particle Volatility Study

Duong Hoang Do,Yanfang Chen,Hyungu Kang,Jeong Jiwoo,Hwajin Kim 한국대기환경학회 2021 한국대기환경학회 학술대회논문집 Vol.2021 No.10

Studying of particle properties in well-controlled environment chamber is significant for the purpose of parameterization as well as enhancing the efficiency of experiment by reducing the timescale. System composed of two connected smog chambers, to generate and measure particle volatility via diluting particles, has been developed. To obtain accurate results, this technique requires optimum diluting rate and correction factors. We conducted experiments at various initial conditions including RH, NOx, mass concentration in 27 m³ chamber. A bellows pump transported sample air to a 6 m³ chamber for dilution. Particle phase was monitered by Aerosol Mass Spectrometer (AMS) and scanning mobility particle sizer (SMPS). Our particle-wall loss rate were consistent with other chamber studies. However, we found that particle at the humid condition (>50%) was likely to coagulate and lost to the Teflon wall faster than lower relative humidity condition. Second, transport flow rate and dilution ratios effects were investigated to determine losses of particles in system. The results provided optimum experimental condition with Seoul relevant condition. Dilution of 10:1 zero air to sample air with transporting flow rate of 100 Lpm resulted less than 20% of particle loss in major particle size range from 100 nm to 400 nm. Further investigation results on SOA mass yield and particle aging will be presented.

Study on Pollen Viability, Longevity and Pistil Receptivity of Self-Compatible Chrysanthemum with Small Inflorescences

Hongbo Zhao,Fadi Chen,Yanfang Wang,Weimin Fang,Sumei Chen,Weiming Guo 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-