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Proline-2′-deoxymugineic acid, a phytosiderophore analog, drives beneficial rhizobacterial community

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023531

摘要：

● Proline-2′-deoxymugineic (PDMA) significantly altered the bacterial community in the peanut rhizosphere.

关键词： Beneficial rhizobacteria recruitment     peanut     plant-soil micronutrition enhancement     proline-2′-deoxymugineic acid     stable microbial network    

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Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

G. Usha RANI,Kartick Prasad DEY,Srijita BHARTI,Sumit MISHRA

《化学科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 465-470 doi: 10.1007/s11705-014-1452-8

摘要： The utilization of poly (2-hydroxyethylmethacrylate) grafted agar (Ag-g-P(HEMA)) as a matrix for the controlled release of 5-aminosalicylic acid was investigated. Grafted copolymers of 2-hydroxyethylmethacrylate (HEMA) monomers on agar were synthesized by microwave assisted method. drug release studies were performed at pH values of 2 and 7 in order to investigate the possibility of pH triggered release for colon targeted drug delivery. Further, the percent grafting . (the time taken for release of 50% of the enclosed drug) value was studied and the results indicate that it may be possible to develop a programmable drug release matrix based on grafted polysaccharide. Ag-g-P(HEMA) appears to be a useful matrix for controlled release.

关键词： agar     controlled drug release     5-Amino salicylic acid     poly(2-hydroxyethylmethacrylate) grafted agar    

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Investigation of the effects of humic acid and H 2 O 2 on the photocatalytic degradation of atrazine

Chao QIN, Shaogui YANG, Cheng SUN, Jia ZHOU, Manjun ZHAN, Rongjun WANG, Huanxing CAI,

《环境科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 321-328 doi: 10.1007/s11783-010-0238-6

摘要： A solution of atrazine in a TiO suspension, an endocrine disruptor in natural water, was tentatively treated by microwave-assisted photocatalytic technique. The effects of mannitol, oxygen, humic acid, and hydrogen dioxide on the photodegradation rate were explored. The results could be deduced as follows: the photocatalytic degradation of atrazine fits the pseudo-first-order kinetic well with = 0.0328 s, and ·OH was identified as the dominant reactant. Photodegradation of atrazine was hindered in the presence of humic acid, and the retardation effect increased as the concentration of humic acid increased. HO displayed a significant negative influence on atrazine photocatalysis efficiency. Based on intermediates identified with gas chromatography-mass spectrometry (GC-MS) and Liquid chromatography-mass spectrometry (LC-MS/MS) techniques, the main degradation routes of atrazine are proposed.

关键词： atrazine     retardation effect     photocatalysis     TiO2    

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Improvement in the synthesis of 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl

GAO Shihao, SUN Chenghui, ZHAO Xinqi, GAO Changquan

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 80-84 doi: 10.1007/s11705-008-0017-0

摘要： 2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl thioester(III), an important intermediate of the fourth generation cephalosporins, was efficiently synthesized by reacting 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid (I) with 2,2′-dibenzothiazole disulfide (II) in the presence of triphenylphosphine. Effects of reaction time, temperature, solvents, catalysts and feeding molar ratio on the yield and quality of products were investigated, and an improved procedure suitable for industrial production was established. Using 1,2-dichloroethane as solvent, triphenylphosphine as reducer, and triethylamine as catalyst, (I) : (II) : (triphenylphosphine) = 1.0 : 1.0 : 1.0, the product was obtained at room temperature in 98.1% yield. The purity of the product without further purification is 98.7% determined by HPLC method. This procedure could be a suitable alternative to the traditional processes because of its easy handling, high yield and low cost.

关键词： 5-Amino-1     2     4-thiadiazol-3-yl     1     2-dichloroethane     important intermediate     2-benzothiazolyl thioester     temperature    

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富含sn-2 DHA脂质对大脑的益处及其酶法合成综述 Review

金俊, 金青哲, 王兴国, Casimir C. Akoh

《工程（英文）》 2020年 第6卷 第4期   页码 424-431 doi: 10.1016/j.eng.2020.02.009

摘要： 甘油酯sn-2位上的DHA可以被肠黏膜更好地吸收，从而实现机体对DHA的高效利用。为了全面了解DHA对大脑的有益功能，本文系统介绍了天然油脂甘油骨架上DHA的位置分布（sn-2和sn-1,3位）特征，并讨论了DHA补充和通过肠-脑轴传递信息的潜在功能机制为了在日常饮食中摄入更多的sn-2 DHA，我们建议通过更为高效和经济的酯交换制造技术生产富含sn-2 DHA脂质，其中需要解决的关键技术包括强化酶的特异性和优化纯化工艺这类饮食可满足对sn-2 关键词： DHA 和 sn-2 DHA     单甘酯     大脑     肠-脑轴     结构脂质    

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Observation on therapeutic efficacy of ursodeoxycholic acid in Chinese patients with primary biliarycirrhosis: a 2-year follow-up study

null

《医学前沿（英文）》 2013年 第7卷 第2期   页码 255-263 doi: 10.1007/s11684-012-0227-1

摘要：

The efficacy of ursodeoxycholic acid (UDCA) on long-term outcome of primary biliary cirrhosis (PBC) has been less documented in Chinese cohort. We aimed to assess the therapeutic effect of UDCA on Chinese patients with PBC. In the present study, 67 patients with PBC were treated with UDCA (13–15 mg?kg-1?day-1) and followed up for 2 years to evaluate the changes of symptoms, laboratory values and histological features. As the results indicated, fatigue and pruritus were obviously improved by UDCA, particularly in patients with mild or moderate symptoms. The alkaline phosphatase and γ-glutamyl transpetidase levels significantly declined at year 2 comparing to baseline values, with the most profound effects achieved in patients at stage 2. The levels of alanine aminotransferase and aspartate aminotransferase significantly decreased whereas serum bilirubin and immunoglobulin M levels exhibited no significant change. Histological feature was stable in patients at stages 1–2 but still progressed in patients at stages 3–4. The biochemical response of patients at stage 2 was much better than that of patients at stages 3–4. These data suggest that, when treated in earlier stage, patients in long-term administration of UDCA can gain favorable results not only on symptoms and biochemical responses but also on histology. It is also indicated that later histological stage, bad biochemical response and severe symptom may be indicators of poor prognosis for UDCA therapy.

关键词： primary biliary cirrhosis     ursodeoxycholic acid     Chinese     biochemical response     therapeutic efficacy    

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Synthesis and bulk polymerization kinetics of monomer dehydroabietic acid-(2-acryloyloxy-ethoxy)-ethyl

Haibo ZHANG,Yanping YANG,He LIU,Jie SONG,Shibin SHANG,Zhanqian SONG

《农业科学与工程前沿（英文）》 2017年 第4卷 第1期   页码 97-105 doi: 10.15302/J-FASE-2016115

摘要： A bulk polymerization monomer dehydro- abietic acid-(2-acryloyloxy-ethoxy)-ethyl ester (DHA-DG-AC) was synthesized from dehydroabietic acid (DHA). The chemical structure of DHA-DG-AC was characterized by H NMR, C NMR, MS and FT-IR. The kinetics of the bulk polymerization of DHA-DG-AC was investigated by Differential Scanning Calorimeter (DSC). Two kinds of kinetic model (nth-order model and autocatalytic model) were used to investigate the polymerization process. The results showed that the experimental DSC curves were consistent with the computational data generated by the autocatalytic kinetic model, and the value of was 95.73 kJ·mol .

关键词： dehydroabietic acid     bulk polymerization     kinetics     autocatalytic kinetic model    

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Resistance to acid degradation, sorptivity, and setting time of geopolymer mortars

Osama A MOHAMED; Rania AL-KHATTAB; Waddah AL-HAWAT

《结构与土木工程前沿（英文）》 2022年 第16卷 第6期   页码 781-791 doi: 10.1007/s11709-022-0862-9

摘要： Experimental evaluations were conducted to determine the water sorptivity, setting time, and resistance to a highly acidic environment, of mortar with alkali-activated ground granulated blast furnace slag (GBS) binder and also of combinations of fly ash and GBS binders. Binders were activated using mixtures of NaOH and Na2SiO3 solutions. The molarity of NaOH in the mixtures ranged from 10 mol·L−1 to 16 mol·L−1, and the Na2SiO3/NaOH ratio was varied from 1.5 to 2.5. Mortar samples were produced using three binder combinations: 1) GBS as the only binder; 2) blended binder with a slag-to-fly ash ratio of 3:1; and 3) mixed binder with 1:1 ratio of slag to fly ash. Mortar samples were mixed and cured at (22 ± 2) °C till the day of the test. The impact of activator solution alkalinity, activator ratio Na2SiO3/NaOH, GBS content on the rate of water absorption were evaluated. After 7, 28, and 90 d of immersion in a 10% sulfuric acid solution, the resistance of a geopolymer matrix to degradation was assessed by measuring the change in sample weight. The influence of solution alkalinity and relative fly ash content on setting times was investigated. Alkali-activated mortar with a slag-to-fly ash ratio of 3:1 had the least sorptivity compared to the two other binder combinations, at each curing age, and for mortars made with each of the NaOH alkaline activator concentrations. Mortar sorptivity decreased with age and sodium hydroxide concentrations, suggesting the production of geopolymerization products. No reduction in weight of sample occurred after immersion in the strong acid H2SO4 solution for three months, regardless of binder combination. This was due to the synthesis of hydration and geopolymerization products in the presence of curing water, which outweighed the degradation of the geopolymer matrix caused by sulfuric acid.

关键词： alkali-activated materials     fly ash     sorptivity     durability of concrete     sodium hydroxide     sodium silicates     reduction in CO2 emissions     sulfuric acid    

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Crk-associated substrate, vascular smooth muscle and hypertension

TANG Dale

《医学前沿（英文）》 2008年 第2卷 第4期   页码 323-331 doi: 10.1007/s11684-008-0062-6

摘要： Hypertension is characterized by vascular smooth muscle constriction and vascular remodeling involving cell migration, hypertrophy and growth. Crk-associated substrate (CAS), the first discovered member of the adapter protein CAS family, has been shown to be a critical cellular component that regulates various smooth muscle functions. In this review, the molecular structure and protein interactions of the CAS family members are summarized. Evidence for the role of CAS in the regulation of vascular smooth muscle contractility is presented. Contraction stimulation induces CAS phosphorylation on Tyr-410 in arterial smooth muscle, creating the binding site for the Src homology (SH) 2/SH3 protein CrkII, which activates neuronal Wiskott-Aldrich syndrome protein (N-WASP)-mediated actin assembly and force development. The functions of CAS in cell migration, hypertrophy and growth are also summarized. Abelson tyrosine kinase (Abl), c-Src, focal adhesion kinase (FAK), proline-rich tyrosine kinase 2 (PYK2), protein tyrosine phosphatase-proline, glutamate, serine and threonine sequence protein (PTP-PEST) and SHP-2 have been documented to coordinate the phosphorylation and dephosphorylation of CAS. The downstream signaling partners of CAS in the context of cell motility, hypertrophy, survival and growth are also discussed. These new findings establish the important role of CAS in the modulation of vascular smooth muscle functions. Furthermore, the upstream regulators of CAS may be new biologic targets for the development of more effective and specific treatment of cardiovascular diseases such as hypertension.

关键词： Contraction stimulation     phosphatase-proline     molecular structure     discovered     hypertension    

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Keratin 5-Cre-driven deletion of

Jun Yang, Lianqing Wang, Yingzhi Huang, Keqiang Liu, Chaoxia Lu, Nuo Si, Rongrong Wang, Yaping Liu, Xue Zhang

《医学前沿（英文）》 2020年 第14卷 第3期   页码 305-317 doi: 10.1007/s11684-019-0722-8

摘要： Familial acne inversa (AI) is an autoinflammatory disorder that affects hair follicles and is caused by loss-of-function mutations in -secretase component genes. We and other researchers showed that ( ) is the most frequently mutated gene in familial AI. In this study, we generated a keratin 5-Cre-driven epidermis-specific conditional knockout mutant in mice. We determined that this mutant recapitulated the major phenotypes of AI, including hyperkeratosis of hair follicles and inflammation. In mice, the IL-36a expression level markedly increased starting from postnatal day 0 (P0), and this increase occurred much earlier than those of TNF- , IL-23A, IL-1 and TLR4. RNA-Seq analysis indicated that Sprr2d, a member of the small proline-rich protein 2 family, in the skin tissues of the mice was also upregulated on P0. Quantitative reverse-transcription polymerase chain reaction showed that other genes had a similar expression pattern. Our findings suggested that IL-36a might be a key inflammatory cytokine in the pathophysiology of AI and involved in the malfunction of the skin barrier in the pathogenesis of AI.

关键词： acne inversa mouse model     interleukin 1 family     member 6     small proline rich protein 2D     key inflammatory cytokine    

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A pulsed switching peroxi-coagulation process to control hydroxyl radical production and to enhance 2,4-Dichlorophenoxyacetic acid degradation

Yaobin Lu, Songli He, Dantong Wang, Siyuan Luo, Aiping Liu, Haiping Luo, Guangli Liu, Renduo Zhang

《环境科学与工程前沿（英文）》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1070-7

摘要：

• A new pulsed switching peroxi-coagulation (PSPC) system was developed.

• The ECT for 2,4-D removal in the PSPC was lower than that in the EF.

• The iron consumption for 2,4-D removal in the PSPC was lower than that in the PC.

关键词： Pulsed switching peroxi-coagulation system     Energy consumption     Hydroxyl radical production     2     4- Dichlorophenoxyacetic acid    

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Electrochemical oxidation of humic acid at the antimony- and nickel-doped tin oxide electrode

TANG Chengli,YAN Wei,ZHENG Chunli

《环境科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 337-344 doi: 10.1007/s11783-013-0545-9

摘要： This work investigated the degradation of humic acid (HA) in aqueous solution by electrochemical oxidation with Antimony- and Nickel-doped Tin oxide electrode (Ni-Sb-SnO /Ti electrode) as the anode. Initial concentrations of HA ranged from 3 to 9 mg·L . Under such a concentration scope, the degradation of HA was a mass transfer controlled process. Degradation rate increased with the increase of HA initial concentration. Test on the effect of tert-butanol revealed that ·OH played an important role in the oxidation of HA. The absence of cation Ca was beneficial to HA degradation, which suggested that both indirect and direct electrolyze happened during the whole electrochemical oxidation process. Alkaly (pH= 12) and neutral (pH= 7) conditions were benefical to HA degradation.

关键词： electrochemical oxidation     humic acid (HA)     natural water     Ni-Sb-SnO2/Ti electrode    

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Vanadium(IV) solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with

《化学科学与工程前沿（英文）》 2023年 第17卷 第1期   页码 56-67 doi: 10.1007/s11705-022-2185-8

摘要： Separation of vanadium from black shale leaching solution at low pH is very meaningful, which can effectively avoid the generation of alkali neutralization slag and the resulting vanadium loss. In this study, coordination mechanism of vanadium in acid leaching solution at low pH was investigated with the intervention of chloride ions. Under the conditions of pH 0.8, di-(2-ethylhexyl)phosphoric acid concentration of 20%, phase ratio of 1:2, and extraction time of 8 min, the vanadium extraction could reach 80.00%. The Fourier transform infrared and electrospray ionization results reveal that, despite the fact that the chloride ion in the leachate could significantly promote vanadium extraction, the chloride ion does not enter the organic phase, indicating an intriguing phenomenon. Among Cl−–V, SO42−–V, and H2O–V, the V–Cl bond is longer and the potential difference between coordinate ions and vanadium is smaller. Therefore, VO2+ gets easily desorbed with chloride ions and enter the organic phase. At the same time, the hydrogen ions of di-(2-ethylhexyl)phosphoric acid also enter the water phase more easily, which reduces the pH required for the extraction reaction.

关键词： vanadium     black shale     solvent extraction     high acidity extraction    

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A study on rapid acid chrome black (MB 7) spectrophotometric determination of ClO

Jing DONG, Huilong WANG

《化学科学与工程前沿（英文）》 2011年 第5卷 第2期   页码 245-251 doi: 10.1007/s11705-010-1003-x

摘要： Experiments were conducted to investigate the degradation of 2,6-dinitro- -cresol (DNPC) in the chlorine dioxide (ClO ) catalytic oxidation process. Pure aluminum oxide was used as the catalyst in this process. The degradation of DNPC by ClO using aluminum oxide as catalyst was systematically studied by varying the experimental parameters, such as pH values, catalyst dosage, the initial concentration of DNPC and ClO , reaction time, etc. Under optimal condition (DNPC concentration 39 mg·L , ClO concentration 0.234 g·L , reaction time 15 min, catalyst dosage 4.7 g·L and pH 4.32), almost complete degradation of DNPC can be achieved. The kinetic studies revealed that the ClO catalytic oxidation degradation of DNPC followed pseudo-first-order kinetics with respect to both ClO and DNPC concentration. The repetitive use of the catalyst was investigated along sequential feed-batch trials. The catalyst performed efficiently after five runs. In addition, a simple and convenient method for the determination of ClO in water was developed by using acid chrome black 7 (MB 7) spectrophotometry in this paper.

关键词： chlorine dioxide     2     6-dinitro-p-cresol (DNPC)     aluminum oxide     water treatment     MB 7 spectrophotometry    

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Inhibition of protein kinase B by Palmitate in the insulin signaling of HepG2 cells and the preventiveeffect of Arachidonic acid on insulin resistance

XIA Yanzhi, WAN Xuedong, DUAN Qiuhong, HE Shansu, WANG Ximing

《医学前沿（英文）》 2007年 第1卷 第2期   页码 200-206 doi: 10.1007/s11684-007-0038-y

摘要： Elevated plasma levels of free fatty acids (FFAs) may contribute to insulin resistance (IR) that is characteristic of type 2 diabetes mellitus. In this study, we investigated the effects of two fatty acids, palmitate (PA) and arach

关键词： palmitate     characteristic     study     plasma     resistance    

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标题 作者 时间 类型 操作

Proline-2′-deoxymugineic acid, a phytosiderophore analog, drives beneficial rhizobacterial community

期刊论文

Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

G. Usha RANI,Kartick Prasad DEY,Srijita BHARTI,Sumit MISHRA

期刊论文

Investigation of the effects of humic acid and H 2 O 2 on the photocatalytic degradation of atrazine

Chao QIN, Shaogui YANG, Cheng SUN, Jia ZHOU, Manjun ZHAN, Rongjun WANG, Huanxing CAI,

期刊论文

Improvement in the synthesis of 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl

GAO Shihao, SUN Chenghui, ZHAO Xinqi, GAO Changquan

期刊论文

富含sn-2 DHA脂质对大脑的益处及其酶法合成综述

金俊, 金青哲, 王兴国, Casimir C. Akoh

期刊论文

Observation on therapeutic efficacy of ursodeoxycholic acid in Chinese patients with primary biliarycirrhosis: a 2-year follow-up study

null

期刊论文

Synthesis and bulk polymerization kinetics of monomer dehydroabietic acid-(2-acryloyloxy-ethoxy)-ethyl

Haibo ZHANG,Yanping YANG,He LIU,Jie SONG,Shibin SHANG,Zhanqian SONG

期刊论文

Resistance to acid degradation, sorptivity, and setting time of geopolymer mortars

Osama A MOHAMED; Rania AL-KHATTAB; Waddah AL-HAWAT

期刊论文

Crk-associated substrate, vascular smooth muscle and hypertension

TANG Dale

期刊论文

Keratin 5-Cre-driven deletion of

Jun Yang, Lianqing Wang, Yingzhi Huang, Keqiang Liu, Chaoxia Lu, Nuo Si, Rongrong Wang, Yaping Liu, Xue Zhang

期刊论文

A pulsed switching peroxi-coagulation process to control hydroxyl radical production and to enhance 2,4-Dichlorophenoxyacetic acid degradation

Yaobin Lu, Songli He, Dantong Wang, Siyuan Luo, Aiping Liu, Haiping Luo, Guangli Liu, Renduo Zhang

期刊论文

Electrochemical oxidation of humic acid at the antimony- and nickel-doped tin oxide electrode

TANG Chengli,YAN Wei,ZHENG Chunli

期刊论文

Vanadium(IV) solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with

期刊论文

A study on rapid acid chrome black (MB 7) spectrophotometric determination of ClO

Jing DONG, Huilong WANG

期刊论文

Inhibition of protein kinase B by Palmitate in the insulin signaling of HepG2 cells and the preventiveeffect of Arachidonic acid on insulin resistance

XIA Yanzhi, WAN Xuedong, DUAN Qiuhong, HE Shansu, WANG Ximing

期刊论文