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Low expression of fatty acid oxidation related gene ACADM indicates poor prognosis of renal clear cell carcinoma and is related to tumor immune infltration
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作者 JIECHUAN QIU TIANMIN YANG +3 位作者 YANNING SUN KAI SUN YINGKUN XU QINGHUA XIA 《Oncology Research》 SCIE 2024年第3期545-561,共17页
This research aims to identify the key fatty acid beta-oxidation(FAO)genes that are altered in kidney renal clear cell carcinoma(KIRC)and to analyze the role of these genes in KIRC The Gene Expression Omnibus(GEO)and ... This research aims to identify the key fatty acid beta-oxidation(FAO)genes that are altered in kidney renal clear cell carcinoma(KIRC)and to analyze the role of these genes in KIRC The Gene Expression Omnibus(GEO)and FAO datasets were used to identify these key genes.Wilcoxon rank sum test was used to assess the levels of acyl-CoA dehydrogenase medium chain(ACADM)between KIRC and non cancer samples.The logistic regression and Wilcoxon rank sum test were used to explore the association between ACADM and clinical features.The diagnostic performance of ACADM for KIRC was asessed using a diagnostic receiver operating ch aracteristic(ROC)curve.The co-expressed genes of ACADM were identifed in LinkedOmics database,and their function and pathway enrichment were analyzed.The correlation between ACADM expression level and immune infitration was analyzed by Gene Set Variation Analysis(GSVA)method Additionally,the proliferation,migration,and invasion abilities of KIRC cells were assessed after overexpressing ACADM.Following differential analysis and intersection,we identifed six hub genes,induding ACADM.We found that the expression level of ACADM was decreased in KIRC tissues and had a better diagnostic efect(AUC=0.916).Survival analysis suggested that patients with decreased ACADM expression had a worse prognosis.According to correlation analysis,a variety of dinical features were associated with the expression level of ACADML By analyzing the infiltration level of immune cells,we found that ACADM may be related to the enrichment of immune cells.Finally,ACADM overexpression inhibited proliferation,migration,and invasion of KIRC cells.In conclusion,our findings suggest that reduced ACADM expression in KIRC patients is indicative of poor prognosis.These results imply that ACADM may be a diagnostic and prognostic marker for individuals with KIRC,offering a reference for dinicians in diagnosis and treatment. 展开更多
关键词 Kidney renal clear cell carcinoma Acyl CoA dehydrogenase medium chain Immune infiltration Fatty acid oxidation Prognosis
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Synergistic extraction of cerium from sulfuric acid medium using mixture of 2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester and Di-(2-ethyl hexyl) phosphoric acid as extractant 被引量:8
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作者 罗兴华 黄小卫 +2 位作者 朱兆武 龙志奇 刘营 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第1期119-122,共4页
Synergistic extraction of cerium(IV) from sulfuric acid medium using mixture of 2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester(HEH/EHP, HL) and Di-(2-ethyl hexyl) phosphoric acid(HDEHP, HA) as extractant... Synergistic extraction of cerium(IV) from sulfuric acid medium using mixture of 2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester(HEH/EHP, HL) and Di-(2-ethyl hexyl) phosphoric acid(HDEHP, HA) as extractant was investigated.The results indicated that the maximum synergistic enhancement coefficients were obtained at the mole fraction of HEH/EHP=0.6, and cerium(IV) was extracted into organic phase in the form of Ce(SO4)0.5HL2A2.A cation exchange mechanism was proposed for the synergistic extraction of Ce(IV).The equilibrium constants and thermodynamic functions such as △G, △H, and △S were determined in the extraction of Ce(IV) from sulfuric medium using mixture of HEH/EHP and HDEHP. 展开更多
关键词 synergistic extraction CERIUM HEH/EHP HDEHP sulfuric acid medium rare earths
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Leaching Behavior and Mechanism of Cement Solidified Heavy Metal Pb in Acid Medium 被引量:1
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作者 周明凯 王彩萍 +1 位作者 CHEN Yan CHEN Xiao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第4期781-786,共6页
The relationship between Pb leaching concentration and the solution's pH with time was analyzed when cement in its solidified form was leached in an acid medium. The effects of the particle size of the solidified for... The relationship between Pb leaching concentration and the solution's pH with time was analyzed when cement in its solidified form was leached in an acid medium. The effects of the particle size of the solidified form, the cement adding method, and the hydration degree on Pb solidification were also investigated. The experimental results indicate that cement is quickly dissolved and hydrated in the acid medium, forming a C-S-H gel or silicic acid sol with good adsorption. When cement-Pb solidified form is leached in an acetate solution, the hydrated product erodes with time, so the Pb concentration increases slightly in the beginning. Then, some of the Pb ions are absorbed by the newly generated silicic acid sol, C-S-H. Others produce Pb(OH)2 precipitation for secondary solidification, leading to a gradual decrease in the Pb concentration in a leaching time of more than two hours. Moreover, the particle size of the solidified form has important effects on the Pb dissolution. When the amount of added cement is low, with a pH of less than 9.5, the solidification affects the sequence of the original cement powder, the cement hydrated powder, and the cement- Pb solidified form. When the added amount of cement increases with a pH of more than 11, the effect of adding methods on solidification decreases, and the solidified form is a little better than others. 展开更多
关键词 CEMENT acid medium heavy metal leaching behavior
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Optimization of Fermentation Medium for Producing α-Hydroxyphenylacetic Acid by Using Plackett-Burman Design and Response Surface Methodology 被引量:2
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作者 Zhiguo Hou Bingmei Chen +4 位作者 Jing Lan Yueman Liu Xiaoping Xu James Yu Gu Junjie Gu 《American Journal of Analytical Chemistry》 2013年第10期594-599,共6页
Plackett-Burman design and response surface methodology were applied in order to optimize the fermentation medium of (R)-α-hydroxyphenylacetic acid ((R)-HPA) producing Bacillus sp. HZG-19. The factors playing importa... Plackett-Burman design and response surface methodology were applied in order to optimize the fermentation medium of (R)-α-hydroxyphenylacetic acid ((R)-HPA) producing Bacillus sp. HZG-19. The factors playing important roles in the production of (R)-HPA were selected based on Plackett-Burman design. The path of steepest ascent was undertaken to optimize said fermentation medium. Finally, the optimal levels of the factors with the greatest change in regard to product yield were further optimized using Box-Behnken and response surface analysis. The optimal conditions were found to be as follows: casein peptone 30.49 (g × L-1), glycerol 14.09 (g × L-1), KH2PO4 0.1345 (g × L-1), K2HPO4 0.01 (g × L-1), CaCl2 0.1 (g × L-1), MnSO4 0.01 (g × L-1). Under the optimal conditions described above, the yield of (R)-HPA reached 63.30%, which indicated an increase of 14.9%, as compared to the yield obtained before optimization. 展开更多
关键词 α-Hydroxyphenylacetic acid FERMENTATION medium BIOTRANSFORMATION RESPONSE Surface Analysis
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Facile, Direct Reaction of Benzaldehydes to 3-Arylprop-2-Enoic Acids and 3-Arylprop-2-Ynoic Acids in Aqueous Medium 被引量:2
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作者 Thies Thiemann Mohamed W. Elshorbagy +5 位作者 Mostafa H. F. A. Salem Siraj A. N. Ahmadani Yosef Al-Jasem Mariam Al Azani Mazen A. M. Al-Sulaibi Bassam Al-Hindawi 《International Journal of Organic Chemistry》 CAS 2016年第2期126-141,共16页
Wittig reactions of benzaldehydes, alkanals, and cycloalkanals as well as of acetophenones are carried out with alkoxycarbonyl methylidenetriphenylphosphoranes in 10 w% aqueous NaOH, where the cinnamates and alkenoate... Wittig reactions of benzaldehydes, alkanals, and cycloalkanals as well as of acetophenones are carried out with alkoxycarbonyl methylidenetriphenylphosphoranes in 10 w% aqueous NaOH, where the cinnamates and alkenoates produced are hydrolysed in situ and the corresponding acids are obtained after mostly simple extractive work-up, often without employing organic solvents. Under the same conditions, benzaldehydes are reacted with alkoxycarbonyl bromomethy-lidenephosphorane to produce 3-arylprop-2-ynoic acids (arylpropiolic acids). 展开更多
关键词 Carboxylic acids Arylpropiolic acids Wittig Olefination One Pot Reaction Aqueous Reaction medium Dehydrobromination HYDROLYSIS
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Acidity and Rare Earth Concentration Effects on Ytterbium Purification by an Electrolysis Reduction in H_2SO_4 Medium
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作者 Zhang Bo Jia Jiangtao +1 位作者 Liao Chunsheng Yan Chunhua 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第1期128-128,共1页
Ytterbium purification by an electrolysis reduction in sulfuric acid medium was investigated without nitrogen or argon protection, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode, respectively.... Ytterbium purification by an electrolysis reduction in sulfuric acid medium was investigated without nitrogen or argon protection, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode, respectively. How the conditions such as the acidities of cathode and anode solutions, and the concentration of Yb( Ⅲ ) to affect the circuit and ratio of Yb( Ⅱ )/Yb ( Ⅲ ) in electrolysis reduction were studied. 展开更多
关键词 acidity of cathode and anode solutions rare earths concentration sulfuric acid medium electrolysis reduction YTTERBIUM
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Geological characters and petrological characters of metamorphosed medium-acidic intrusive complexes in Ludong Orogenic Belt,China
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作者 凌贤长 胡庆立 王丽霞 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第1期16-23,共8页
Ludong orogenic belt in China is an importantal continent collision orogenic belt in eastern Asia, between Sino Korean landmass and Yangtze landmass. The host rock of the orogenic belt is metamorphosed medium acidic i... Ludong orogenic belt in China is an importantal continent collision orogenic belt in eastern Asia, between Sino Korean landmass and Yangtze landmass. The host rock of the orogenic belt is metamorphosed medium acidic intrusive complexes, which can be divided into four types, that’s, quartz dioritz, granite dioritz, monzonitic granite and undertint monzonitic granite, principal minerals are plagioclases, potassium feldspars and quartzs, minor minerals are hornblendes, biotites, clinopyxenes and garnets, accessory mineral types and assemblages are very similar, specially, various rocks are mainly fine grained textures. They have the history of regional amphibolite facies metamorphism and deep middle shallow structural layer deformation, and are changed into various gneiss and tectonic system. There are many xenolithes of middle Proterozoic eclogite host rock extrahigh high pressure metamorphic complexes, a small xenolithes of early Proterozoic layered metamorphite system and granulites, and ultrabasic basic rocks of various epoches in the metamorphosed medium acidic intrusive complexes. 展开更多
关键词 Ludong OROGENIC belt in China metamorphosed medium acidIC INTRUSIVE complexes Sino Korean landmass yangtze landmass
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Application of response surface methodology in medium optimization for pyruvic acid production of Torulopsis glabrata TP19 in batch fermentation 被引量:9
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作者 ZHANG Jian GAO Nian-fa 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第2期98-104,共7页
Response surface methodology (RSM) was used to optimize the fermentation medium for enhancing pyruvic acid production by Torulopsis glabrata TP19. In the first step of optimization, with Plackett-Burman design, ammoni... Response surface methodology (RSM) was used to optimize the fermentation medium for enhancing pyruvic acid production by Torulopsis glabrata TP19. In the first step of optimization, with Plackett-Burman design, ammonium sulfate, glucose and nicotinic acid were found to be the important factors affecting pyruvic acid production significantly. In the second step, a 23 full factorial central composite design and RSM were applied to determine the optimal concentration of each significant variable. A second-order polynomial was determined by the multiple regression analysis of the experimental data. The optimum values for the critical components were obtained as follows: ammonium sulfate 0.7498 (10.75 g/L), glucose 0.9383 (109.38 g/L) and nicotinic acid 0.3633 (7.86 mg/L) with a predicted value of maximum pyruvic acid production of 42.2 g/L. Under the optimal conditions, the practical pyruvic acid production was 42.4 g/L. The determination coefficient (R2) was 0.9483, which ensures adequate credibility of the model. By scaling up fermentation from flask to jar fermentor, we obtained promising results. 展开更多
关键词 发酵法 丙酮酸 中磷铸铁闸瓦 表面反应
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Efficacy of medium-chain fatty acid salts distilled from coconut oil against two enteric pathogen challenges in weanling piglets 被引量:7
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作者 Paola López-Colom Lorena Castillejos +3 位作者 Agustina Rodríguez-Sorrento Mónica Puyalto Juan JoséMallo Susana María Martín-Orúe 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2020年第1期251-267,共17页
Background:The search for alternatives to antibiotics in pig production has increased the interest in natural resources with antimicrobial properties,such as medium-chain fatty acids(MCFA)as in-feed additives.This stu... Background:The search for alternatives to antibiotics in pig production has increased the interest in natural resources with antimicrobial properties,such as medium-chain fatty acids(MCFA)as in-feed additives.This study evaluated the potential of a novel blend of MCFA salts(DIC)from distilled coconut oil with a lauric acid content to reduce enteropathogens and control intestinal diseases around weaning.Two experimental disease models were implemented in early-weaned piglets,consisting of two oral challenges:Salmonella Typhimurium(1.2×10~8 CFU)or enterotoxigenic Escherichia coli(ETEC)F4(1.5×10~9 CFU).The parameters assessed were:animal performance,clinical signs,pathogen excretion,intestinal fermentation,immune-inflammatory response,and intestinal morphology.Results:The Salmonella challenge promoted an acute course of diarrhea,with most of the parameters responding to the challenge,whereas the ETEC F4 challenge promoted a mild clinical course.A consistent antipathogenic effect of DIC was observed in both trials in the hindgut,with reductions in Salmonella spp.plate counts in the cecum(P=0.03)on d 8 post-inoculation(PI)(Salmonella trial),and of enterobacteria and total coliform counts in the ileum and colon(P<0.10)on d 8 PI(ETEC F4 trial).When analyzing the entire colonic microbiota(16 S rRNA gene sequencing),this additive tended(P=0.13)to reduce the Firmicutes/Bacteroidetes ratio and enriched Fibrobacteres after the Salmonella challenge.In the ETEC F4 challenge,DIC prompted structural changes in the ecosystem with increases in Dialister,and a trend(P=0.14)to increase the Veillonellaceae family.Other parameters such as the intestinal fermentation products or serum pro-inflammatory mediators were not modified by DIC supplementation,nor were the histological parameters.Only the intraepithelial lymphocyte(IEL)counts were lowered by DIC in animals challenged with Salmonella(P=0.07).With ETEC F4,the IEL counts were higher with DIC on d 8 PI(P=0.08).Conclusions:This study confirms the potential activity of this MCFA salts mixture to reduce intestinal colonization by opportunistic pathogens such as Salmonella or E.coli and its ability to modulate colonic microbiota.These changes could explain to some extent the local immune cell response at the ileal level. 展开更多
关键词 ENTERIC PATHOGEN Gut MICROBIOTA Intestinal immunity medium-chain fatty acids WEANING pig
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Ball-milling MoS_2/carbon black hybrid material for catalyzing hydrogen evolution reaction in acidic medium 被引量:1
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作者 Jiayuan Li Dunfeng Gao +3 位作者 Jing Wang Shu Miao Guoxiong Wang Xinhe Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第5期608-613,共6页
Replacing platinum for catalyzing hydrogen evolution reaction (HER) in acidic medium remains great chal- lenges. Herein, we prepared few-layered MoS2 by ball milling as an efficient catalyst for HER in acidic medium... Replacing platinum for catalyzing hydrogen evolution reaction (HER) in acidic medium remains great chal- lenges. Herein, we prepared few-layered MoS2 by ball milling as an efficient catalyst for HER in acidic medium, The activity of as-prepared MoS2 had a strong dependence on the ball milling time, Furthermore, Ketjen Black EC 300J was added into the ball-milled MoS2 followed by a second ball milling, and the resultant MoS2/carbon black hybrid material showed a much higher HER activity than MoS2 and carbon black alone. The enhanced activity of the MoS2/carbon black hybrid material was attributed to the increased abundance of catalytic edge sites of MoS) and excellent electrical coupling to the underlving carbon network. 展开更多
关键词 Molybdenum disulfide Carbon black Hybrid material Ball milling Hydrogen evolution reaction acidic medium
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Enhanced Oil Recovery by Injecting Oleic Acid as a Surfactant into the Porous Medium
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作者 Mmadi Salim Mohamed Sosse Ndyaye +2 位作者 Kharouna Talla Cheikh Mbow Aboubaker Chedikh Beye 《Open Journal of Fluid Dynamics》 2020年第1期82-94,共13页
Physico-chemical methods of improved oil recovery make it possible to increase oil production in deposits by injecting surfactants acting on various physical parameters. Oleic acid has an effect on the viscosity of th... Physico-chemical methods of improved oil recovery make it possible to increase oil production in deposits by injecting surfactants acting on various physical parameters. Oleic acid has an effect on the viscosity of the displacement fluid and the flow rate. Therefore, increasing the viscosity of the displacement fluid plays an essential role in improving the improved oil recovery. The physicochemical properties at the interface between petroleum and water are modified by oleic acid, lowering the viscosity of petroleum and increasing the viscosity of water, which facilitated the mobility of petroleum in the porous medium. 展开更多
关键词 Porous medium Complex FLUIDS SURFACTANT Oleic acid TWO-PHASE FLOWS
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N/S co-doped 3D carbon framework prepared by a facile morphology-controlled solid-state pyrolysis method for oxygen reduction reaction in both acidic and alkaline media 被引量:2
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作者 Juan Nong Min Zhu +4 位作者 Kun He Aosheng Zhu Pu Xie Minzhi Rong Mingqiu Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第7期220-226,共7页
Developing high-performance non-precious metal electrocatalysts for oxygen reduction reaction(ORR)is crucial for the commercialization of fuel cells and metal-air batteries.However,doped carbon-based materials only sh... Developing high-performance non-precious metal electrocatalysts for oxygen reduction reaction(ORR)is crucial for the commercialization of fuel cells and metal-air batteries.However,doped carbon-based materials only show good ORR activity in alkaline medium,and become less effective in acidic environment.We believe that an appropriate combination of both ionic and electronic transport path,and well dopant distribution of doped carbon-based materials would help to realize high ORR performance un-der both acidic and alkaline cond让ions.Accordingly,a nitrogen and sulfur co-doped carbon framework with hierarchical through-hole structure is fabricated by morphology-controlled solid-state pyrolysis of poly(aniline-co-2-ami no thiophenol)foam.The uniform high concentrations of nitrogen and sulfur,high intrinsic conductivity,and integrated three dimensional ionic and electronic transfer passageways of the 3D porous structure lead to synergistic effects in catalyzing ORR.As a result,the limiting current density of the carbonized poly(aniline-co-2-aminothiophenol)foam is equivalent to commercial Pt/C in acidic environment,and twice the latter in alkaline medium. 展开更多
关键词 3D N/S-doped CARBON frameworks Oxygen reduction reaction(ORR) Morphology-retaining PYROLYSIS acidIC medium
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Effect of Indole 3-Butyric Acid and Media Type on Adventitious Root Formation in Sheanut Tree (<i>Vitellaria paradoxa</i>C. F. Gaertn.) Stem Cuttings 被引量:4
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作者 Daniel Brain Akakpo Naalamle Amissah +1 位作者 Julius Yeboah Essie Blay 《American Journal of Plant Sciences》 2014年第3期313-318,共6页
Shea nuts play an important role in food security for rural folks within sub-Sahara Africa, serving as the main source of income for many people living in Northern Ghana. Unfortunately, the full economic potential of ... Shea nuts play an important role in food security for rural folks within sub-Sahara Africa, serving as the main source of income for many people living in Northern Ghana. Unfortunately, the full economic potential of the Sheanut tree has not been fully realized due to the difficulty involved in its domestication. This difficulty in vegetatively propagating sheanut trees has greatly hindered its cultivation and the realization of its true economic potential. Two experiments were conducted to investigate the effects of rooting media and varying indole 3-butyric acid (IBA) concentrations on adventitious root formation in cuttings taken from coppiced sheanut trees. Results indicated that 3000 ppm produced significantly (p 0.05) better rooting (57.5%) than 5000 ppm (30%), 7000 ppm (45.0%) and the control (7.5%). Although the levels of soluble sugars (SS) and total free phenols (TFP) in the cutting were significantly (p 0.05) higher at the end of the experiment (after IBA treatment) compared to the start (prior to IBA treatment), the SS and TFP trends observed did not clearly explain the rooting differences found between the IBA levels investigated. Callus formation was significantly (p 0.05) higher (35.0%) in the control (no IBA). Generally, callus formation decreased with increasing IBA concentration. In the rooting media experiment, rooting was significantly (p 0.05) higher in the rice husk medium (35.0%) compared to that in the palm fiber (18.3%), saw dust (14.1%) and top soil (16.7%) media. 展开更多
关键词 Coppiced INDOLE 3-Butyric acid Sheanut TREE Cuttings Rooting medium
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Degradation mechanisms of poly (lactic-co-glycolic acid) films in vitro under static and dynamic environment 被引量:2
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作者 黄莹莹 齐民 +2 位作者 张萌 刘洪泽 杨大智 《中国有色金属学会会刊:英文版》 CSCD 2006年第B01期293-297,共5页
To understand their degradation mechanisms, PLGA (50:50) polymer films were prepared and eroded in the static and dynamic medium system. The degradation behavior was characterized through weight-average molecular weig... To understand their degradation mechanisms, PLGA (50:50) polymer films were prepared and eroded in the static and dynamic medium system. The degradation behavior was characterized through weight-average molecular weight change, mass loss, water uptake, etc. The results show that in dynamic system, significant mass loss begins until 10 d while mass loss does not begin until 30 d later, while weight-average molecular weight decreases observably at the beginning, and the appeasable mass loss happens in 20 d in static system, which suggests that the dynamic degradation rate is slower even than degradation in static medium. A mechanism was proposed that specimens in static medium take up water homogeneously and cause the polymer chains to degrade all over the specimen cross sections, which creates free carboxylic acid groups which lead to a decrease of pH value inside the swollen polymer and accelerate degradation of the polymer. While pH value inside polymer keeps constant in dynamic medium because of flowing of simulated medium, which make the hydrolytic cleavage of ester bonds inside specimen delayed. 展开更多
关键词 聚乳酸-乙醇酸共聚物 薄膜 水解 降解机制 静力环境 动力环境 缓释体系
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Isolation, Purification, and Identification of a Novel HX-Producing Strain and Optimization of Its Fermentation Medium
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作者 Zhengkai Xue Wenwu Zheng 《Food and Nutrition Sciences》 2018年第5期447-463,共17页
Hexanoic acid (HX) is a crucial flavor compound and precursor of ethyl caproate (EA), which determines the quality of Chinese Luzhou-flavor liquor (CLFL). The isolation, purification, identification, and optimization ... Hexanoic acid (HX) is a crucial flavor compound and precursor of ethyl caproate (EA), which determines the quality of Chinese Luzhou-flavor liquor (CLFL). The isolation, purification, identification, and optimization of fermentation conditions of HX-producing bacteria are essential for industrial CLFL production. In this study, one strain of HX-producing bacterium was isolated from six candidate bacterial strains and identified as Clostridium sartagoneforme. Then, the growth characteristics and HX production of C. sartagoneforme were investigated. Sodium acetate medium was identified as the optimal fermentation medium from four candidate media. C. sartagoneforme yielded 800.85 ± 12.87 mg/100mL HX in sodium acetate medium. Then, to further optimize the formula of the fermentation medium, the carbon and nitrogen sources and inorganic salt component of the fermentation medium were investigated using HX yields as an optimization index. Optimization was performed with a single-factor experiment and the Taguchi design method. The single-factor experiment showed that the highest HX outputs were obtained when the sodium acetate medium contained 2.5 g/L yeast extract, 1.8 g/L KCl, 20 g/L sodium acetate, 15 mL/L ethanol, and 1.5 g/L glucose. In the orthogonal experiment designed using the Taguchi design method, HX yields reached 2018.29 ± 46.37 mg/100mL in sodium acetate medium that contained 3.5 g/L yeast extract, 1.8 g/L KCl, 25 g/L sodium acetate, and 15 mL/L ethanol. 展开更多
关键词 ISOLATION IDENTIFICATION Hexanoic acid-Producing STRAIN FERMENTATION medium Optimization
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Dorsal root ganglion-derived Schwann cells combined with poly(lactic-co-glycolic acid)/chitosan conduits for the repair of sciatic nerve defects in rats 被引量:3
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作者 Li Zhao Wei Qu +2 位作者 Yuxuan Wu Hao Ma Huajun Jiang 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第22期1961-1967,共7页
Schwann cells, nerve regeneration promoters in peripheral nerve tissue engineering, can be used to repair both the peripheral and central nervous systems. However, isolation and puriifcation of Schwann cells are compl... Schwann cells, nerve regeneration promoters in peripheral nerve tissue engineering, can be used to repair both the peripheral and central nervous systems. However, isolation and puriifcation of Schwann cells are complicated by contamination with ifbroblasts. Current reported measures are mainly limited by either high cost or complicated procedures with low cell yields or purity. In this study, we collected dorsal root ganglia from neonatal rats from which we obtained highly puriifed Schwann cells using serum-free melanocyte culture medium. The purity of Schwann cells (〉95%) using our method was higher than that using standard medium containing fetal bovine serum. The obtained Schwann cells were implanted into poly(lactic-co-glycolic acid)/chi-tosan conduits to repair 10-mm sciatic nerve defects in rats. Results showed that axonal diameter and area were signiifcantly increased and motor functions were obviously improved in the rat sciatic nerve tissue. Experimental ifndings suggest that serum-free melanocyte culture medium is conducive to purify Schwann cells and poly(lactic-co-glycolic acid)/chitosan nerve conduits combined with Schwann cells contribute to restore sciatic nerve defects. 展开更多
关键词 nerve regeneration Schwann cells dorsal root ganglia melanocyte medium FIBROBLASTS poly(lactic-co-glycolic acid CHITOSAN sciatic nerve defect NSFC grants neural regeneration
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Comparative Study of the Kinetics of Dissolution of Laterite in some Acidic Media 被引量:1
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作者 Olushola S. AYANDA Folahan A. ADEKOLA +2 位作者 Alafara A. BABA Olalekan S. FATOKI Bhekumusa J. XIMBA 《Journal of Minerals and Materials Characterization and Engineering》 2011年第15期1457-1472,共16页
Studies on the kinetics of dissolution of a Nigerian lateritic soil in acids media including hydrochloric, nitric and sulphuric acids have been undertaken. The elemental and mineralogical characterization, loss of mas... Studies on the kinetics of dissolution of a Nigerian lateritic soil in acids media including hydrochloric, nitric and sulphuric acids have been undertaken. The elemental and mineralogical characterization, loss of mass on ignition, moisture content and pH of the material suspension in water were determined. The effects of acid concentration, process temperature, stirring rate and particle size on the dissolution rate were investigated. Experimental results indicated that laterite dissolution was greatly influenced by hydrogen ion concentration and the leaching data fitted a diffusion model. The linear dependence of the rate constant k on 1/ro 2 supported the proposed kinetic model. Values of 60.23 kJmol-1, 64.31 kJmol-1 and 67.53 kJmol-1 were obtained for the activation energies of laterite dissolution in hydrochloric, nitric and sulphuric acids respectively;and the order of reaction was approximately one with respect to each of the three acids. 展开更多
关键词 Lateritic soil DISSOLUTION KINETICS hydrochloric acid nitric acid Sulphuric acid.
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Effects of medium chain triglycerides on hepatic fatty acid oxidation in clofibrate-fed newborn piglets 被引量:1
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作者 Jinan Zhao Brandon Pike +3 位作者 Jin Huang Zhihua Feng Jack Odle Xi Lin 《Animal Nutrition》 SCIE CSCD 2023年第1期334-344,共11页
To investigate whether increasing tricarboxylic acid(TCA)cycle activity and ketogenic capacity would augment fatty acid(FA)oxidation induced by the peroxisome proliferator-activated receptor-alpha(PPARα)agonist clofi... To investigate whether increasing tricarboxylic acid(TCA)cycle activity and ketogenic capacity would augment fatty acid(FA)oxidation induced by the peroxisome proliferator-activated receptor-alpha(PPARα)agonist clofibrate,suckling newborn piglets(n=54)were assigned to 8 groups following a 2(±clofibrate)×4(glycerol succinate[SUC],triglycerides of 2-methylpentanoic acid[T2M],valeric acid[TC5]and hexanoic acid[TC6])factorial design.Each group was fed an isocaloric milk formula containing either 0%or 0.35%clofibrate(wt/wt,dry matter basis)with 5%SUC,T2M,TC5 or TC6 for 5 d.Another 6 pigs served as newborn controls.Fatty acid oxidation was examined in fresh homogenates of liver collected on d 6 using[1-^(14)C]palmitic acid(1 mM)as a substrate(0.265μCi/μmol).Measurements were performed in the absence or presence of L-carnitine(1 mM)or inhibitors of 3-hydroxy-3-methylglutaryl-CoA synthase(L659699,1.6μM)or acetoacetate-CoA deacylase(iodoacetamide,50μM).Without clofibrate stimulation,^(14)C accumulation in CO_(2) was higher from piglets fed diets containing T2M and TC5 than SUC,but similar to those fed TC6.Under clofibrate stimulation,accumulation also was higher in homogenates from piglets fed TC5 than all other dietary treatments.Interactions between clofibrate and carnitine or the inhibitors were observed(P=0.0004)for acid soluble products(ASP).In vitro addition of carnitine increased^(14)C-ASP(P<0.0001)above all other treatments,regardless of clofibrate treatment.The percentage of^(14)C in CO_(2) was higher(P=0.0023)in TC5 than in the control group.From these results we suggest that dietary supplementation of anaplerotic and ketogenic FA could impact FA oxidation and modify the metabolism of acetyl-CoA(product ofβ-oxidation)via alteration of TCA cycle activity,but the modification has no significant impact on the hepatic FA oxidative capacity induced by PPARα.In addition,the availability of carnitine is a critical element to maintain FA oxidation during the neonatal period. 展开更多
关键词 PPARΑ CLOFIBRATE Newborn piglets medium chain triglyceride(MCT) Hepatic fatty acid oxidation
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A Suitable Culture Medium for the Production of Exopolysaccharide by Streptococcus salivarius subsp.thermophilus
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作者 GURui-xia LIUAi-ping 《Journal of Northeast Agricultural University(English Edition)》 CAS 2000年第1期43-49,共7页
A new culture medium for the synthesis of exopolysaccharide by streptococcus salivarius subsp.thermophilus was formulated,based on MRS,M17,ATP,SL,Elliker,SDM usually used in lactic acid bacterium.The suitability of a ... A new culture medium for the synthesis of exopolysaccharide by streptococcus salivarius subsp.thermophilus was formulated,based on MRS,M17,ATP,SL,Elliker,SDM usually used in lactic acid bacterium.The suitability of a semi defined culture media (named LCX) was obtained.The formula of culture medium was optimized as:peptone,1.50%,typtone,1.00%;K 2HPO 4,0.20%;MgSO 4.7H 2O,0.02%;MnSO 4.4H 2O,50 mg·L -1 ;Tween 80,1ml·L -1 ;Sodium acetate,0.50%;Sodium glycerate,1.90%. 展开更多
关键词 lactic acid bacteria EXOPOLYSACCHARIDE medium
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Investigate the Corrosion Inhibition of Mild Steel in Sulfuric Acid Solution by Thiosemicarbazide
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作者 Fatma Mohamed Mahgoub S. M. Al-Rashdi 《Open Journal of Physical Chemistry》 2016年第3期54-66,共13页
Corrosion inhibition of mild steel in 0.5 mol/L H<sub>2</sub>SO<sub>4</sub> was investigated in the absence and presence of different concentrations of thiosemicarbazide. The inhibition efficie... Corrosion inhibition of mild steel in 0.5 mol/L H<sub>2</sub>SO<sub>4</sub> was investigated in the absence and presence of different concentrations of thiosemicarbazide. The inhibition efficiency of thiosemicarbazide was studied by electrochemical impedance methods, potentiodynamic polarization and scanning electron microscopy at different inhibitor concentrations. Inhibition efficiency, corrosion rate and surface coverage were evaluated at different concentrations of thiosemicarbazide. Electrochemical impedance plots indicated that the presence of the inhibitors increased the charge transfer resistance of the corrosion process, increasing the inhibition efficiency. Polarization curves showed that this compound acted as mixed type inhibitor. The results of the investigation showed that this compound had good inhibiting properties for mild steel corrosion in 0.5 M sulfuric acid. The adsorption isotherm studies showed that Thiosemicarbazide adsorbed chemisorbed and formed a stable surface complex on the mild steel surface. And Langmuir obeyed the adsorption isotherm. Scanning electron microscopy analysis shows that, the surface morphology of the polished mild steel in the presence of thiosemicarbazide as inhibitor is smoother surface as compared with polished mild steel specimen in the absence of inhibitor. 展开更多
关键词 acidic medium ADSORPTION Inhibitor Mild Steel and SEM
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