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Synthesis and

Wen Zhao, Jiahua Xing, Tianming Xu, Weili Peng, Xinghai Liu

《化学科学与工程前沿（英文）》 2017年 第11卷 第3期   页码 363-368 doi: 10.1007/s11705-016-1595-x

摘要： Pyrazole carboxamide derivatives represent an important class of fungicides in agrochemicals. To find more novel structural pyrazole carboxamides, a novel series of 3-(trifluoromethyl)-1 -pyrazole-4-carboxamide compounds were prepared from ethyl 4,4,4-trifluoroacetoacetate and triethyl orthoformate as starting materials. All the products were characterized by Fourier transform infrared spectroscopy, H nuclear magnetic resonance (NMR), C NMR, F NMR and mass spectrography. The bioassay results showed these fluorine-containing pyrazole carboxamides have a weak fungicidal activity but some of them exhibit a good nematocidal activity against .

关键词： fluorinated pyrazole carboxamide     synthesis     nematocidal activity     structure and activity relationship    

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IDEEA activity monitor: validity of activity recognition for lying, reclining, sitting and standing

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 126-131 doi: 10.1007/s11684-012-0236-0

摘要：

Recent evidence demonstrates the independent negative effects of sedentary behavior on health, but there are few objective measures of sedentary behavior. Most instruments measure physical activity and are not validated as measures of sedentary behavior. The purpose of this study was to evaluate the validity of the IDEEA system’s measures of sedentary and low-intensity physical activities: lying, reclining, sitting and standing. Thirty subjects, 14 men and 16 women, aged 23 to 77 years, body mass index (BMI) between 18 to 34 kg/m2, participated in the study. IDEEA measures were compared to direct observation for 27 activities: 10 lying in bed, 3 lying on a sofa, 1 reclining in a lawn chair, 10 sitting and 3 standing. Two measures are reported, the percentage of activities accurately identified and the percentage of monitored time that was accurately labeled by the IDEEA system for all subjects. A total of 91.6% of all observed activities were accurately identified and 92.4% of the total monitored time was accurately labeled. The IDEEA system did not accurately differentiate between lying and reclining so the two activities were combined for calculating accuracy. Using this approach the IDEEA system accurately identified 96% of sitting activities for a total of 97% of the monitored sitting time, 99% and 99% for standing, 87% and 88% for lying in bed, 87% and 88% for lying on the sofa, and 83% and 83% for reclining on a lawn chair. We conclude that the IDEEA system accurately recognizes sitting and standing positions, but it is less accurate in identifying lying and reclining positions. We recommend combining the lying and reclining activities to improve accuracy. The IDEEA system enables researchers to monitor lying, reclining, sitting and standing with a reasonable level of accuracy and has the potential to advance the science of sedentary behaviors and low-intensity physical activities.

关键词： IDEEA     activity monitor     sedentary behavior    

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Production of pectic extracts from sugar beet pulp with antiproliferative activity on a breast cancer

Jacqueline CONCHA, Caroline WEINSTEIN, María Elvira Zú?IGA

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 482-489 doi: 10.1007/s11705-013-1342-5

摘要： In the last years, sugar beet pectins have been the subject of several investigations involving extraction methodologies, chemical composition and functional properties. The structure of pectins, which depends on the extraction method, is decisive in their capacity to induce apoptosis on several cancer cell lines like colon, prostate and breast. In this work, sugar beet pectin extraction was performed in the following steps: lipid extraction with hexane, removal of soluble complex carbohydrates and proteins, and enzymatic treatment with amyloglucosidase, protease, and pectinase. The enzymatic treatment was carried out with Rohapect DA6L under the following conditions: 50°C, pH 4.0, 2% enzyme/substrate (E/S) ratio, 15 h, and a solid to liquid ratio of 1 ∶ 10. The pectic extract showed a degree of polymerization (DP) profile of 55.8% with DP≥7; 4.9% with DP6; 5.8% between DP2 and DP6 ; 4.7% with DP2; and 28.8% with DP1. The pectic extract was examined for its antiproliferative activity on the MCF-7 breast cancer cell line. At a concentration range of 12.5–25 mg/mL the pectic extract killed 80.6% of the cells, exhibiting a higher antiproliferative activity than 4-hydroxytamoxifen (4-OHT), a classical anticancer drug, which killed 56.5% of the cells.

关键词： pectic extracts     antiproliferative activity     breast cancer     enzymatic treatment    

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Effect of 2-butenal manufacture wastewater to methanogenic activity and microbial community

Guangqing Song, Hongbo Xi, Xiumei Sun, Yudong Song, Yuexi Zhou

《环境科学与工程前沿（英文）》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1056-5

摘要：

The inhibition ratio sharply increased with the increasing COD.

The absorbance of UV-vis at 420 nm showed a linear correlation with the SMA.

The molecular structure of EPS has changed when COD was 9585 mg/L.

Illumina Miseq sequencing was employed to reveal the microbial composition.

关键词： 2-butenal manufacture wastewater     Methanogenic activity     Specific methanogenic activity (SMA)     Extracellular polymeric substance (EPS)     Microbial community    

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Low intensity ultrasound stimulates biological activity of aerobic activated sludge

LIU Hong, YAN Yixin, WANG Wenyan, YU Yongyong

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 67-72 doi: 10.1007/s11783-007-0013-5

摘要： This work aims to explore a procedure to improve biological wastewater treatment efficiency using low intensity ultrasound. The aerobic activated sludge from a municipal wastewater treatment plant was used as the experimental material. Oxygen uptake rate (OUR) of the activated sludge (AS) was determined to indicate the changes of AS activity stimulated by ultrasound at 35 kHz for 0 40 min with ultrasonic intensities of 0 1.2 W/cm. The highest OUR was observed at the ultrasonic intensity of 0.3 W/cm and an irradiation period of 10 min; more than 15% increase was achieved immediately after sonication. More significantly, the AS activity stimulated by ultrasound could last 24 h after sonication, and the AS activity achieved its peak value within 8 h after sonication, or nearly 100% higher than the initial level after sonication. Therefore, to improve the wastewater treatment efficiency of bioreactors, ultrasound with an intensity of 0.3 W/cm could be employed to irradiate a part of the AS in the bioreactor for 10 min every 8 h.

关键词： sonication     irradiation     kHz     treatment efficiency     AS activity    

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A survey of physical activity among urban women in China

Shilin DENG MD, Tongyuan LIU,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 463-469 doi: 10.1007/s11684-009-0081-y

摘要： Few studies have been conducted to assess the level of physical activity (PA) of women in China. The purpose of this study was to describe the prevalence of PA among women in Wuhan and explore sociodemographic and behavioral correlation to PA for the population. A total of 1359 community-dwelling women (42.9713.60 years old) participated in this study. The long-version IPAQ was used to define the level of PA. 45.7% of women were considered physically active, and 27.5% were vigorously active. The proportion of physical inactivity was around 26.8%. The total and 4 domains of PA showed significant age, education level, and occupation variation. PA tended to be lower as the age declined. PA in transportation, housework, leisure time, and the total tended to be the lowest or the second lowest among the women aged 18–35 years old. PA tended to be lower as the level of education increased. Among the 5 indices, PAwas the lowest among women with college education, especially those with postgraduate education. PA tended to be the lowest among the women of office staff and instructor or technician. Generally, the total and 4 domains of PA showed significant age, education level, and occupation variation. Physical inactivity appears to be more common among younger women, or college-educated women, office ladies, and female instructor and technicians.

关键词： physical activity     urban women     China    

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preparation of Ag@AgCl/Bio-veins composites and their photocatalytic activity and recyclability

《化学科学与工程前沿（英文）》 2023年 第17卷 第7期   页码 906-917 doi: 10.1007/s11705-022-2273-9

摘要： The industrial application of nano-photocatalysts in wastewater treatment has been severely restricted for a long time due to their difficult separation, poor reusability, and low efficiency. In this work, a facile strategy was proposed to enhance the photocatalytic activity and recovery performance of Ag@AgCl nanocatalysts. Biological veins (Bio-veins) with a unique 3D porous construction were used as carriers for the in-situ growth of Ag@AgCl nanoparticles. Scanning electron microscopy results showed that the Ag@AgCl nanoparticles were uniformly loaded on the surface and interior of the Bio-veins, and the size of the Ag@AgCl nanoparticles immobilized on the Bio-veins (50–300 nm) was significantly smaller than Ag@AgCl obtained by the co-precipitation method (1–3 μm). The Bio-veins played a vital role in the photocatalysis reaction system. The degradation efficiency of the Ag@AgCl/Bio-veins(CI4) was up to 3.50 times as high as pure Ag@AgCl. Furthermore, the composites also exhibited excellent recyclability and stability under both visible and solar light. This work provided a suitable strategy for nano-photocatalysts for practical application and may also offer new possibilities for the high-value utilization of biomass materials.

关键词： Ag@AgCl     biological veins     photocatalytic activity     recyclability    

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Antithrombin deficiency and decreased protein C activity in a young man with venous thromboembolism:

null

《医学前沿（英文）》 2018年 第12卷 第3期   页码 319-323 doi: 10.1007/s11684-017-0553-4

摘要：

Antithrombin and protein C are two crucial members in the anticoagulant system and play important roles in hemostasis. Mutations in and lead to deficiency or dysfunction of the two proteins, which could result in venous thromboembolism (VTE). Here, we report a Chinese 22-year-old young man who developed recurrent and serious VTE in cerebral veins, visceral veins, and deep veins of the lower extremity. Laboratory tests and direct sequencing of and were conducted for the patient and his family members. Coagulation tests revealed that the patient presented type I antithrombin deficiency combined with decreased protein C activity resulting from a small insertion mutation c.848_849insGATGT in and a short deletion variant c.572_574delAGA in . This combination of the two mutations was absent in 400 healthy subjects each from southern and northern China. Then, we summarized all the mutations of the and gene reported in the Chinese Han population. This study demonstrates that the combination of antithrombin deficiency and decreased protein C activity can result in severe VTE and that the coexistence of different genetic factors may increase the risk of VTE.

关键词： antithrombin deficiency     protein C activity     mutation     variant     venous thromboembolism     anticoagulants    

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Probing the catalytic activity of M-N

Fan Ge, Qingan Qiao, Xin Chen, You Wu

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1206-1216 doi: 10.1007/s11705-020-2017-7

摘要： In this work, the detailed oxygen reduction reaction (ORR) catalytic performance of M-N O (M= Fe, Co, and Ni; = 1–4) has been explored via the detailed density functional theory method. The results suggest that the formation energy of M-N O shows a good linear relationship with the number of doped O atoms. The adsorption manner of O on M-N O changed from end-on ( = 1 and 2) to side-on ( = 3 and 4), and the adsorption strength gradually increased. Based on the results for binding strength of ORR intermediates and the Gibbs free energy of ORR steps on the studied catalysts, we screened out two highly active ORR catalysts, namely Co-N O and Ni-N O , which possess very small overpotentials of 0.27 and 0.32 V, respectively. Such activities are higher than the precious Pt catalyst. Electronic structure analysis reveals one of the reasons for the higher activity of Co-N O and Ni-N O is that they have small energy gaps and moderate highest occupied molecular orbital energy levels. Furthermore, the results of the density of states reveal that the O doping can improve the electronic structure of the original catalyst to tune the adsorption of the ORR intermediates.

关键词： M-N-C catalyst     oxygen doping     oxygen reduction reaction     catalytic activity     density functional theory    

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Catalytic activity of manganese oxide supported on alumina in the synthesis of quinoxalines

Rekha M., H. Kathyayini, N. Nagaraju

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 415-421 doi: 10.1007/s11705-013-1360-3

摘要： Two catalysts, alumina and manganese oxide supported on alumina, have been prepared by calcination and precipitation-impregnation methods, respectively. The catalysts are characterised by the following techniques: Brunner-Emmett-Teller-N adsorption-desorption for surface area, temperature programmed desorption of NH and -butyl amine back titration methods for surface acidity, powder X-ray diffraction for textural properties, and Fourier transform infrared spectroscopy for the anionic radicals. The catalytic activity has been determined under heterogeneous conditions in the condensation reaction between -phenylenediamine and benzil. The product purity is checked by thin-layer chromatography and melting point. The products are also analysed by LC-MS and H-NMR techniques. The yields of the products have been found to be good and catalysts exhibited excellent recyclability. The effect of changing the reaction parameters such as temperature, reaction time, amount of the catalyst, nature of solvent and molar ratio of reactants on the yield of the product has been studied. The surface acidity of the catalysts plays an important role in activating the reaction.

关键词： alumina     manganese oxide deposited on alumina     quinoxaline synthesis    

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Design, synthesis, biological activity and density function theory study of pyrazole derivatives containing

Xiaoming Ding, Zhiwen Zhai, Luping Lv, Zhaohui Sun, Xinghai Liu

《化学科学与工程前沿（英文）》 2017年 第11卷 第3期   页码 379-386 doi: 10.1007/s11705-017-1634-2

摘要： A variety of pyrazole derivatives containing 1,3,4-thiadiazole moiety were synthesized under microwave irradiation, and their structures were confirmed by H NMR and HRMS. They were evaluated for herbicidal and antifungal activities, and the results indicated that two compounds with a phenyl group ( ) and 4- -butylphenyl group ( ) possess good herbicidal activity for dicotyledon and with the inhibition of 90% for root and 80%–90% for stalk at 100 ppm respectively. The structure-activity relationship of compounds and was also studied by density function theory method.

关键词： pyrazole     1     3     4-thiadiazole     antifungal activity     herbicidal activity     density function theory    

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QUANTITATIVE STUDY ON ANTI-PEST ACTIVITY OF NATURAL PRODUCTS BASED ON VISUALIZATION FRAMEWORK OF KNOWLEDGE

《农业科学与工程前沿（英文）》 2023年 第10卷 第2期   页码 306-332 doi: 10.15302/J-FASE-2023488

摘要：

● Using visual analysis to predict the trend of natural product pest resistance.

关键词： anti-pest activity     crop protection     insect pest     natural product     visual analysis    

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Mapping the structure-activity relationship of

Worawan PANPIPAT, Hasene KESKIN, Zheng GUO

《化学科学与工程前沿（英文）》 2015年 第9卷 第1期   页码 105-113 doi: 10.1007/s11705-015-1502-x

摘要： The phase behavior of twelve synthesized -sitosteryl fatty acid esters with acyl moieties with different chain lengths (C2:0-C18:0) and different degrees of unsaturation (C18:1-C18:3) were investigated in pure and mixed Langmuir monolayers with phospholipids. The surface-pressure isotherms showed that short chain -sitosteryl fatty acid esters gave smaller mean molecular areas and had decreased monolayer stability and the long chain steryl esters did not produce collapsed plateaus. All the steryl esters displayed strong condensing effects, but there was a pronounced structural dependency: medium chain esters (C8 and C10) were less efficient than short and long chain esters. Atomic force microscopy imaging demonstrated that monolayers mixed with dipalmitoyl phosphatidylcholine (DPPC) displayed both DPPC-rich and steryl lipid-rich domains. However, the height and area differences between the two phases and the roughness and morphologic patterns were very dependent on the steryl lipid concentrations as well as the length, the degree of unsaturation and the molecular conformations of the acyl segments. These findings not only provide a better understanding of the interactions between phytosteryl hydrophobic derivatives and biomembranes, but also may be of general use for the design and engineering of phytosterol structural derivations for specific food and pharmaceutical applications.

关键词： β-sitosteryl fatty acid esters     dipalmitoyl phosphatidylcholine     Langmuir monolayer     condensing effect     structure-activity relationship    

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Diagnostic evaluation of plasma aldosterone concentration to plasma renin activity ratio in primary aldosteronism

ZHANG Huilan, WANG Daowen

《医学前沿（英文）》 2008年 第2卷 第1期   页码 11-14 doi: 10.1007/s11684-008-0003-4

摘要： Using the plasma aldosterone concentration to plasma renin activity ratio (PAC/PRA ratio) as the screening test of choice for primary aldosteronism in hypertensive patients, we studied the clinical characteristics and the diagnostic value of PAC/PRA ratio in primary aldosteronism. The plasma aldosterone concentration (PAC) and plasma renin activity (PRA) levels were measured by radioimmunoassay in 902 hypertensive patients from out-patient clinics or hospitals. One hundred and twenty-six suspected primary aldosteronism patients whose PAC/PRA ratio was > 25 ng/dL/ng/mL/hr had a lamellar computed tomography (CT) scan in the adrenal gland and follow-up visits. The proportion of primary aldosteronism in hypertensive patients was 14% (126/902). There were 54 patients with unilateral or bilateral hyperplasia and 25 patients with adenoma according to the CT scan. 39% (49/126) of the patients with primary aldosteronism had hypokalemia. Twenty-five patients received surgical treatment. The efficacy and cure rates were 100% (25/25) and 48% (12/25), respectively. The effective rate of aldactone and the single-drug cure rate were 89% (48/54) and 24% (13/54), respectively. Primary aldosteronism affects over 10% of hypertensive patients in China. The PAC/PRA ratio can be considered as a routine screening test in hypertensives, especially resistant hypertensive patients and a high PAC/PRA ratio is an invaluable index in primary aldosteronism diagnosis.
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Covalent triazine framework with efficient photocatalytic activity in aqueous and solid media

Cyrine Ayed, Wei Huang, Kai A. I. Zhang

《化学科学与工程前沿（英文）》 2020年 第14卷 第3期   页码 397-404 doi: 10.1007/s11705-019-1884-2

摘要： Covalent triazine frameworks (CTFs) have been recently employed for visible light-driven photocatalysis due to their unique optical and electronic properties. However, the usually highly hydrophobic nature of CTFs, which originates from their overall aromatic backbone, leads to limitations of CTFs for applications in aqueous media. In this study, we aim to extend the range of the application media of CTFs and design hybrid material of a CTF and mesoporous silica (SBA-15) for efficient photocatalysis in aqueous medium. A thiophene-containing CTF was directly synthesized in mesopores of SBA-15. Due to the high surface area and the added hydrophilic properties by silica, the hybrid material demonstrated excellent adsorption of organic molecules in water. This leads not only to high photocatalytic performance of the hybrid material for the degradation of organic dyes in water, but also for efficient photocatalysis in solvent-free and solid state. Furthermore, the reusability, stability and easy recovery of the hybrid material offers promising metal-free heterogeneous photocatalyst for broader applications in different reaction media.

关键词： photocatalysis     covalent triazine framework     aqueous medium     SBA-15     solid state    

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标题 作者 时间 类型 操作

Synthesis and

Wen Zhao, Jiahua Xing, Tianming Xu, Weili Peng, Xinghai Liu

期刊论文

IDEEA activity monitor: validity of activity recognition for lying, reclining, sitting and standing

null

期刊论文

Production of pectic extracts from sugar beet pulp with antiproliferative activity on a breast cancer

Jacqueline CONCHA, Caroline WEINSTEIN, María Elvira Zú?IGA

期刊论文

Effect of 2-butenal manufacture wastewater to methanogenic activity and microbial community

Guangqing Song, Hongbo Xi, Xiumei Sun, Yudong Song, Yuexi Zhou

期刊论文

Low intensity ultrasound stimulates biological activity of aerobic activated sludge

LIU Hong, YAN Yixin, WANG Wenyan, YU Yongyong

期刊论文

A survey of physical activity among urban women in China

Shilin DENG MD, Tongyuan LIU,

期刊论文

preparation of Ag@AgCl/Bio-veins composites and their photocatalytic activity and recyclability

期刊论文

Antithrombin deficiency and decreased protein C activity in a young man with venous thromboembolism:

null

期刊论文

Probing the catalytic activity of M-N

Fan Ge, Qingan Qiao, Xin Chen, You Wu

期刊论文

Catalytic activity of manganese oxide supported on alumina in the synthesis of quinoxalines

Rekha M., H. Kathyayini, N. Nagaraju

期刊论文

Design, synthesis, biological activity and density function theory study of pyrazole derivatives containing

Xiaoming Ding, Zhiwen Zhai, Luping Lv, Zhaohui Sun, Xinghai Liu

期刊论文

QUANTITATIVE STUDY ON ANTI-PEST ACTIVITY OF NATURAL PRODUCTS BASED ON VISUALIZATION FRAMEWORK OF KNOWLEDGE

期刊论文

Mapping the structure-activity relationship of

Worawan PANPIPAT, Hasene KESKIN, Zheng GUO

期刊论文

Diagnostic evaluation of plasma aldosterone concentration to plasma renin activity ratio in primary aldosteronism

ZHANG Huilan, WANG Daowen

期刊论文

Covalent triazine framework with efficient photocatalytic activity in aqueous and solid media

Cyrine Ayed, Wei Huang, Kai A. I. Zhang

期刊论文