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Impacts of Human Activities and Season on Species Diversity and Abundance of Butterflies in Mpanga Kipengere Game Reserve and Surrounding Farmlands, Tanzania
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作者 Privatus M. Kasisi Nsajigwa Mbije Paul Lyimo 《Open Journal of Ecology》 2024年第4期274-291,共18页
Maintaining natural habitats is crucial for the preservation of insects and other species that indicate environmental changes. However, the Mpanga/Kipengere Game Reserve and its surrounding farmlands are facing distur... Maintaining natural habitats is crucial for the preservation of insects and other species that indicate environmental changes. However, the Mpanga/Kipengere Game Reserve and its surrounding farmlands are facing disturbance due to human activities, which is putting many wildlife species, particularly larger mammals, at risk. To determine the impact of human activities on butterfly species diversity and abundance in the reserve and its surrounding areas, we conducted a study from November 2021 to October 2023. We collected butterfly data using transect walks and baited traps in two habitat types. Our study yielded 2799 butterfly Individuals ranging in 124 species divided into five families habitat, season, and anthropogenic factors are significant environmental variables influencing species diversity and abundance of butterflies. Therefore, it’s important to protect habitat and dry-season water for the conservation of invertebrates such as butterflies. Our study findings provide essential information for ecological monitoring and future assessment of the Mpanga/Kipengere Game Reserve ecosystem health. 展开更多
关键词 Mpanga Kipengere Game Reserve species Diversity HABITAT Butterflies SEASON Human activities
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Evaluation of Reactive Oxygen Species (ROS) Generated on the Surface of Copper Using Chemiluminesence
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作者 Ken Hirota Hiroya Tanaka +4 位作者 Taika Maeda Kazuhiko Tsukagoshi Hiroshi Kawakami Takashi Ozawa Masahiko Wada 《Materials Sciences and Applications》 2023年第10期482-499,共18页
The antibacterial activity of copper is well-known from an ancient civilization, however, its biocidal mechanism has not been necessarily elucidated. Notwithstanding up to now, mainly 4 processes have been proposed. A... The antibacterial activity of copper is well-known from an ancient civilization, however, its biocidal mechanism has not been necessarily elucidated. Notwithstanding up to now, mainly 4 processes have been proposed. Among them, it is cleared that 4 kinds of reactive oxygen species (ROS): hydroxyl radical ·OH, hydrogen per oxide H<sub>2</sub>O<sub>2</sub>, superoxide anion ·O<sup>-</sup>2</sub></sub>   and singlet oxygen <sup>1</sup>O<sub>2</sub>, play an important role for contact-killing of bacteria, viruses and fungi. In this paper, generation of ROS on the surfaces of copper plates heated from room temperature to 673 K for 4.2 × 10<sup>2</sup> s in air, was investigated using the chemiluminescence. ROS have been evaluated by selecting the most suitable scavengers, such as 2-propanol for ·OH, sodium pyruvate for H<sub>2</sub>O<sub>2</sub>, nitro blue tetrazolium for ·O<sup>-</sup>2</sub></sub>,  and sodium azide NaN<sub>3</sub> for <sup>1</sup>O<sub>2</sub>. At the same time the outermost surface of copper, on which thin film of cuprous oxide Cu<sub>2</sub>O was first formed and then cupric oxide CuO was laminated on Cu<sub>2</sub>O, was examined by thin-film XRD and TEM analysis to estimate the amounts and kinds of copper oxides. It was found that the most amounts of ROS were obtained for the 573 K-heated Cu plate and they were composed of ·OH, H<sub>2</sub>O<sub>2</sub>, and ·O<sup>-</sup>2.</sub></sub>. 展开更多
关键词 COPPER Microbial activity Reactive Oxygen species CHEMILUMINESCENCE SCAVENGERS
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Synergistic activation of smithsonite with copper-ammonium species for enhancing surface reactivity and xanthate adsorption 被引量:1
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作者 Wenjuan Zhao Bin Yang +2 位作者 Yahui Yi Qicheng Feng Dianwen Liu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第4期519-527,共9页
Copper ions(Cu^(2+))are usually added to activate the sulfidized surface of zinc oxide minerals to enhance xanthate attachment using sulfidization xanthate flotation technology.The adsorption of Cu^(2+)and xanthate on... Copper ions(Cu^(2+))are usually added to activate the sulfidized surface of zinc oxide minerals to enhance xanthate attachment using sulfidization xanthate flotation technology.The adsorption of Cu^(2+)and xanthate on the sulfidized surface was investigated in various systems,and its effect on the surface hydrophobicity and flotation performance was revealed by multiple analytical methods and experiments.X-ray photoelectron spectroscopy(XPS)and time-of-flight secondary ion mass spectrometry(To F-SIMS)characterization demonstrated that the adsorption of Cu^(2+)on sulfidized smithsonite surfaces increased the active Cu—S content,regardless of treatment in any activation system.The sulfidized surface pretreated with NH_(4)^(+)-Cu^(2+)created favorable conditions for the adsorption of more Cu^(2+),significantly enhancing the smithsonite reactivity.Zeta potential determination,ultraviolet(UV)-visible spectroscopy,Fourier transform-infrared(FT-IR)measurements,and contact angle detection showed that xanthate was chemically adsorbed on the sulfidized surface,and its adsorption capacity in various systems was illustrated from qualitative and quantitative aspects.In comparison to the Na2S–Cu^(2+)and Cu^(2+)–Na2S–Cu^(2+)systems,xanthate exhibited a higher adsorption capacity on sulfidized smithsonite surfaces in NH_(4)^(+)-Cu^(2+)–Na2S–Cu^(2+)system.Hence,activation with Cu^(2+)–NH4+synergistic species prior to sulfidization significantly enhanced the mineral surface hydrophobicity,thereby increasing its flotation recovery. 展开更多
关键词 Smithsonite surface reactivity Synergistic activation Copper-ammonium species Surface hydrophobicity Enhanced recovery
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Aromatization over nanosized Ga-containing ZSM-5 zeolites prepared by different methods:Effect of acidity of active Ga species on the catalytic performance 被引量:8
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作者 Yujun Fang Xiaofang Su +4 位作者 Xuefeng Bai Wei Wu Gaoliang Wang Linfei Xiao Anran Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第4期768-775,共8页
Nanosized Ga-containing ZSM-5 zeolites were prepared via isomorphous substitution and impregnation followed by characterized using various techniques. The catalytic performance of the zeolites for the aromatization of... Nanosized Ga-containing ZSM-5 zeolites were prepared via isomorphous substitution and impregnation followed by characterized using various techniques. The catalytic performance of the zeolites for the aromatization of 1-hexene was investigated. The results indicate that isomorphous substitution promotes the incorporation of Ga heteroatoms into the framework along with the formation of extra-framework GaO;species([GaO;]a) that have stronger interactions with the negative potential of the framework. In addition, based on the Py-IR results and catalytic performance, the [GaO;]aspecies with stronger Lewis acid sites produced a better synergism with moderate Br?nsted acid sites and thus improved the selectivity to aromatic compounds. However, the impregnation results in the formation of Ga;O;phase and small amounts of GaO;species that are mainly located on the external surface([GaO;];), which contribute to weaker Lewis acid sites due to weaker interactions with the zeolite framework. During 1-hexene aromatization, the nanosized Ga isomorphously substituted ZSM-5 zeolite samples(Gax-NZ5) exhibited better catalytic performance compared to the impregnated samples, and the highest aromatic yield(i.e.,65.4 wt%) was achieved over the Ga4.2-NZ5 sample, which contained with the highest Ga content. 展开更多
关键词 Nanosized ZSM-5 zeolite Isomorphous substitution IMPREGNATION active gallium species AROMATIZATION
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Degradation of Organic Compounds by Active Species Sprayed in a Dielectric Barrier Corona Discharge System 被引量:4
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作者 李杰 宋玲 +3 位作者 刘强 屈广周 李国锋 吴彦 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第2期211-215,共5页
Investigation was made into the degradation of organic compounds by a dielectric barrier corona discharge (DBCD) system. The DBCD, consisting of a quartz tube, a concentric high voltage electrode and a net wrapped t... Investigation was made into the degradation of organic compounds by a dielectric barrier corona discharge (DBCD) system. The DBCD, consisting of a quartz tube, a concentric high voltage electrode and a net wrapped to the external wall (used as ground electrode), was introduced to generate active species which were sprayed into the organic solution through an aerator fixed on the bottom of the tube. The effect of four factors-the discharge voltage, gas flow rate, solution conductivity, and pH of wastewater, on the degradation efficiency of phenol was assessed. The obtained results demonstrated that this process was an effective method for phenol degradation. The degradation rate was enhanced with the increase in power supplied. The degradation efficiency in alkaline conditions was higher than those in acid and neutral conditions. The optimal gas flow rate for phenol degradation in the system was 1.6 L/min, while the solution conductivity had little effect on the degradation. 展开更多
关键词 dielectric barrier corona discharge (DBCD) active species organic compound degradation wastewater treatment
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Reactive oxygen species-induced activation of Yes-associated protein-1 through the c-Myc pathway is a therapeutic target in hepatocellular carcinoma 被引量:1
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作者 Yuri Cho Min Ji Park +4 位作者 Koeun Kim Sun Woong Kim Wonjin Kim Sooyeon Oh Joo Ho Lee 《World Journal of Gastroenterology》 SCIE CAS 2020年第42期6599-6613,共15页
BACKGROUND The Hippo signaling pathway regulates organ size by regulating cell proliferation and apoptosis with terminal effectors including Yes-associated protein-1(YAP-1).Dysregulation in Hippo pathway has been prop... BACKGROUND The Hippo signaling pathway regulates organ size by regulating cell proliferation and apoptosis with terminal effectors including Yes-associated protein-1(YAP-1).Dysregulation in Hippo pathway has been proposed as one of the therapeutic targets in hepatocarcinogenesis.The levels of reactive oxygen species(ROS)increase during the progression from early to advanced hepatocellular carcinoma(HCC).AIM To study the activation of YAP-1 by ROS-induced damage in HCC and the involved signaling pathway.METHODS The expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761)was quantified using real-time polymerase chain reaction and immunoblotting.Human HCC cells were treated with H2O2,which is a major component of ROS in living organisms,and with either YAP-1 small interfering RNA(siRNA)or control siRNA.To investigate the role of YAP-1 in HCC cells under oxidative stress,MTS assays were performed.Immunoblotting was performed to evaluate the signaling pathway responsible for the activation of YAP-1.Eighty-eight surgically resected frozen HCC tissue samples and 88 nontumor liver tissue samples were used for gene expression analyses.RESULTS H2O2 treatment increased the mRNA and protein expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761).Suppression of YAP-1 using siRNA transfection resulted in a significant decrease in tumor proliferation during H2O2 treatment both in vitro and in vivo(both P<0.05).The oncogenic action of YAP-1 occurred via the activation of the c-Myc pathway,leading to the upregulation of components of the unfolded protein response(UPR),including 78-kDa glucoseregulated protein and activating transcription factor-6(ATF-6).The YAP-1 mRNA levels in human HCC tissues were upregulated by 2.6-fold compared with those in nontumor tissues(P<0.05)and were positively correlated with the ATF-6 Levels(Pearson’s coefficient=0.299;P<0.05).CONCLUSION This study shows a novel connection between YAP-1 and the UPR through the c-Myc pathway during oxidative stress in HCC.The ROS-induced activation of YAP-1 via the c-Myc pathway,which leads to the activation of the UPR pathway,might be a therapeutic target in HCC. 展开更多
关键词 Hepatocellular carcinoma Yes-associated protein-1 C-MYC Reactive oxygen species Unfolded protein response activating transcription factor-6
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Reactive oxygen species: A double-edged sword in oncogenesis 被引量:13
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作者 Jin-Shui Pan Mei-Zhu Hong Jian-Lin Ren 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第14期1702-1707,共6页
Reactive oxygen species (ROS) are molecules or ions formed by the incomplete one-electron reduction of oxygen. Ofinterest, it seems that ROS manifest dual roles, cancer promoting or cancer suppressing, in tumorigenesi... Reactive oxygen species (ROS) are molecules or ions formed by the incomplete one-electron reduction of oxygen. Ofinterest, it seems that ROS manifest dual roles, cancer promoting or cancer suppressing, in tumorigenesis. ROS participate simultaneously in two signaling pathways that have inverse functions in tumorigenesis, Ras-Raf-MEK1/2-ERK1/2 signaling and the p38 mitogen-activated protein kinases (MAPK) pathway. It is well known that Ras-Raf-MEK1/2-ERK1/2 signaling is related to oncogenesis, while the p38 MAPK pathway contributes to cancer suppression, which involves oncogene-induced senescence, inflammationinduced cellular senescence, replicative senescence, contact inhibition and DNA-damage responses. Thus, ROS may not be an absolute carcinogenic factor or cancer suppressor. The purpose of the present review is to discuss the dual roles of ROS in the pathogenesis of cancer, and the signaling pathway mediating their role in tumorigenesis. 展开更多
关键词 癌症抑制 活性氧 P38丝裂原活化蛋白激酶 P38蛋白激酶 信号通路 物种 信号转导通路 肿瘤发生
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Organogermanium (Ge-132) Suppresses Activities of Stress Enzymes Responsible for Active Oxygen Species in Monkey Liver Preparation 被引量:1
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作者 Takafumi Tezuka Atsunori Higashino +1 位作者 Mitsuo Akiba Takashi Nakamura 《Advances in Enzyme Research》 2017年第2期13-23,共11页
Assays of stress enzymes related to active oxygen species were performed by using an in vitro preparation from the liver of a monkey (Japanese Macaque). Ge-132, an organic germanium compound, viz. poly-trans-[(2-carbo... Assays of stress enzymes related to active oxygen species were performed by using an in vitro preparation from the liver of a monkey (Japanese Macaque). Ge-132, an organic germanium compound, viz. poly-trans-[(2-carboxyethyl) germasesquioxane] [(GeCH2CH2COOH)2O3]n, suppressed the activities of NADH-dependent oxidase and NADPH-dependent oxidase [NAD(P)H-OD] and xanthine oxidase (XOD) as superoxide-forming enzymes, while promoting the activities of superoxide dismutase (SOD) as a superoxide-scavenging enzyme and catalase (CAT) as an enzyme responsible for degradation of hydrogen peroxide (H2O2). The evidence suggests that the levels of active oxygen species such as and H2O2 would be reduced by Ge-132. The possible connection between Ge-132 and activities of stress enzymes is discussed on the basis of these results. 展开更多
关键词 active Oxygen species Stress ENZYMES [CAT NAD(P)H-OD SOD XOD] GE-132 [(GeCH2CH2COOH)2O3]n MONKEY LIVER
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Elucidation of Active Species over Ru/MnO Catalyst on Co<sub>2</sub>/H<sub>2</sub>Methanation Reaction 被引量:1
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作者 Wan Azelee Wan Abu Bakar Susilawati Toemen +1 位作者 Rusmidah Ali Hazwan Faiz Abd Rahim 《Advances in Materials Physics and Chemistry》 2013年第2期161-167,共7页
The information regarding phase changes and structure transformation, particle sizes as well as active species of the catalyst are briefly discussed towards alumina supported Ru/MnO catalysts according to their variou... The information regarding phase changes and structure transformation, particle sizes as well as active species of the catalyst are briefly discussed towards alumina supported Ru/MnO catalysts according to their various parameters of calcination temperatures and Mn loading. The Ru/Mn-75/Al2O3 catalysts calcined at 400°C, 700°C, 900°C, 1000°C and 1100°C, Ru/Mn-65/Al2O3 and Ru/Mn-85/Al2O3 catalyst calcined at 1000°C were synthesized by the wetness impregnation method. All the prepared catalysts exhibited crystallite size in the range of 95 nm to 114 nm. It was found that the catalyst with Ru/Mn-75/Al2O3 calcined at 1000°C showed the highest 60.21% CO2 conversion with 57.84% formation of CH4 at the reaction temperature 200°C. The expected active species that assist the CO2 methanation activity over this catalyst was Mn3O4. 展开更多
关键词 X-Ray DIFFRACTION CO2 METHANATION CATALYSTS active species
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Gallic Acid Isolated from Pomegranate Peel Extract Induces Reactive Oxygen Species Mediated Apoptosis in A549 Cell Line
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作者 Santhini Elango Ramji Balwas Viswanadha Vijaya Padma 《Journal of Cancer Therapy》 2011年第5期638-645,共8页
Antioxidant properties elicited by plant species have a full range of perspective applications in human health care. In recent years, the prevention of cancer and cardiovascular diseases has been associated with the i... Antioxidant properties elicited by plant species have a full range of perspective applications in human health care. In recent years, the prevention of cancer and cardiovascular diseases has been associated with the ingestion of fresh fruits, vegetables or teas rich in natural antioxidants [1]. Extracts from the different part of the pomegranate plant such as juice, seed and peel have been reported to exhibit a potent antioxidant activity. But the anticarcinogenic activity of active principle from the pomegranate peel extract was not studied so far. Hence the present study was planned to explore the molecular mechanism of the anticarcinogenic activity pomegranate peel on A549 cell line. In this study, GC-MS analysis was carried out for the methanolic extract of pomegranate peel which revealed gallic acid (GA) as the major antioxidant compound in the extract. Hence GA was purified further through RP-HPLC and evaluated its anticancer potential by studying its effect on mitochondrial respiration, cell-membrane integrity, apoptotic body formation and the DNA fragmentation in cultured A549 cells. We observed increased level of reactive oxygen species in the cells treated with GA at the concentrations of 10 and 20 ug/ml. Further analysis of caspase activation (caspase 8 and 9) revealed activation of caspases 9 in the cells treated with GA at a concentration of 20 ug/ml. Thus the present study revealed that the GA isolated from the pomegranate peel extract (Kabul variety) induced apoptosis in A549 cells through intrinsic pathway. 展开更多
关键词 POMEGRANATE Anticarcinogenic activity REactive OXYGEN species APOPTOSIS
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Tocilizumab Significantly Decreases Reactive Oxygen Species Level in Patients with Rheumatoid Arthritis
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作者 Naoki Kondo Katsumitsu Arai +6 位作者 Takahiro Netsu Tomotake Kanai Hiroshige Sano Go Okumura Yasufumi Kijima Junichi Fujisawa Naoto Endo 《Open Journal of Rheumatology and Autoimmune Diseases》 2017年第1期46-52,共7页
To determine the effect of tocilizumab (TCZ) on reactive oxygen species (ROS) in 11 patients with rheumatoid arthritis (RA), reactive oxygen metabolites (d-ROM) were measured using a Free Radical Elective Evaluator. T... To determine the effect of tocilizumab (TCZ) on reactive oxygen species (ROS) in 11 patients with rheumatoid arthritis (RA), reactive oxygen metabolites (d-ROM) were measured using a Free Radical Elective Evaluator. The Disease Activity Score (DAS28) and matrix metalloproteinase-3 (MMP-3) level were also evaluated. d-ROM measured 392 ± 110 Carratelli units [U. CARR] on initiation of TCZ, and significantly decreased to 237 ± 82, 248 ± 88, and 226 ± 91 U.CARR after 3, 6, and 12 months, respectively 展开更多
关键词 TOCILIZUMAB RHEUMATOID ARTHRITIS REactive Oxygen species Disease activity SCORE 28
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JWA is required for arsenic trioxide induced apoptosis in HeLa and MCF-7 cells via reactive oxygen species and mitochondria linked signal pathway 被引量:8
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作者 Zhou, J. H. Ye, J. Zhao, X. J. Li, A. P. Zhou, J. W. 《南京医科大学学报(自然科学版)》 CAS CSCD 北大核心 2008年第12期1648-1648,共1页
关键词 基因 三氧化二砷 诱导方法 细胞凋亡 活性氧 线粒体
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Effects of Tannic Acid on Active Aluminum Species Distribution in Various Tea Soils
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作者 You-Jian Su Wan-You Liao +3 位作者 Ye-Jun Wang Yong-Li Zhang Yi Luo Shan-Guo Hu 《茶叶》 2013年第4期299-307,共9页
Effects of tannic acid on active aluminum species distribution in different pH tea soils in Yunnan and Jiangxi tea gardens were studied by field observation and laboratory analysis.There were 4 species of active alumi... Effects of tannic acid on active aluminum species distribution in different pH tea soils in Yunnan and Jiangxi tea gardens were studied by field observation and laboratory analysis.There were 4 species of active aluminum in the tea soil,i.e.,exchangeable aluminum Al3 +,unimer hydroxyl aluminum Al(OH)2 +Al(OH)+2,acid-soluble aluminum Al(OH)03and humic-acid aluminum Al-HA.Experimental results showed that tannic acid at levels 0 ~0.4 mmol/kg and 0 ~ 2.0 mmol/kg,with the rising of soil pH value,the content of exchangeable aluminum decreased significantly,hydroxyl aluminum,acid-soluble aluminum and humic-acid aluminum were increased gently.When the concentration of tannic acid increased to above 2.0 mmol/kg,the inhibition of higher concentration of tannic acid on content of active aluminum was strengthened with the rising of soil pH value and variation law of 20 ~ 40 cm soil layer was similar to 0 ~ 20cm soil layer.Generally speaking,the content of active aluminum in upper layer of soil were more than subsoil and total content of active aluminum in Yunnan tea soils were higher than Jiangxi tea soils.The correlation analysis showed that the soil pH were positively correlated with hydroxyl aluminum,humic-acid aluminum,pHBC(r = 0.796,0.960,0.852;p < 0.01,0.01,0.01) in 0 ~ 20cm soil layer.pHBC were significant negative correlated with exchangeable aluminum(r =- 904,p < 0.01),hydroxyl aluminum(r =- 645,p < 0.05),and with humic-acid aluminum have a positive correlation,correlation coefficient was0.795(P < 0.05).Meanwhile,the tannic acid addition concentration were 0 ~ 0.4 mmol/kg soils pH were increased significantly,while samples attains a peak pH value afterwards decrease continuously,the relationship between the pH and the concentration of tannic acids accords with the equation:Y pH=- 0.04C DN+3.82(R2= 0.95,P < 0.01).When the concentration of tannic acid up to about 8.0 ~ 12.0 mmol/kg,soil pH keep unchanged.Therefore,we can clearly draw that effects of tannic acid on active aluminum content of the inflection point is not the same in different region of tea garden soil.Low concentration tannic acid can improve the soil content of various forms of aluminum,but with the increase in the amount of tannic acid,the various forms of aluminum content are inhibited.With the soil pH increased,high concentrations tannic acid on the inhibition of the release of active aluminum increased.pH and tannic acid on the total amount of active aluminum garden soil was mutual weakening effect relationship. 展开更多
关键词 铝形态分布 土壤活性 茶园土壤 单宁酸 土壤PH值 浓度增加 实验室分析 交换性铝
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Au^(δ-)-O_(v)-Ti^(3+):Active site of MO_(x)-Au/TiO_(2) catalysts for the aerobic oxidation of 5-hydroxymethylfurfural
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作者 Weiyao Yang Mengchen Fu +2 位作者 Chenyu Yang Yiwen Zhang Chun Shen 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期785-797,共13页
Despite wide applications of noble metal-based catalysts in 5-hydroxymethylfurfural(HMF)oxidation,promoting the catalytic performance at low loading amounts still remains a significant challenge.Herein,a series of met... Despite wide applications of noble metal-based catalysts in 5-hydroxymethylfurfural(HMF)oxidation,promoting the catalytic performance at low loading amounts still remains a significant challenge.Herein,a series of metal oxide modified MO_(x)-Au/TiO_(2)(M=Fe,Co,Ni)catalysts with low Au loading amount of 0.5 wt%were synthesized.Addition of transition metal oxides promotes electron transfer and generation of the Au^(δ-)-O_(v)-Ti^(3+)interface.A combination study reveals that the dual-active site(Au^(δ-)-O_(v)-Ti^(3+))governs the catalytic performance of the ratedetermining step,namely hydroxyl group oxidation.Au^(δ-) site facilitates chemisorption and activation of O_(2) molecules.At the same time,O_(v)-Ti^(3+) site acts as the role of“killing two birds with one stone”:enhancing adsorption of both reactants,accelerating the activation and dissociation of H_(2)O,and facilitating activation of the adsorbed O_(2).Besides,superoxide radicals instead of base is the active oxygen species during the rate-determining step.On this basis,a FDCA yield of 71.2% was achieved under base-free conditions,complying with the“green chemistry”principle.This work provides a new strategy for the transition metal oxides modification of Au-based catalysts,which would be constructive for the rational design of other heterogeneous catalysts. 展开更多
关键词 5-HYDROXYMETHYLFURFURAL Base-free oxidation Interfacial catalysis active oxygen species
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Soil functional indicators in mixed beech forests are clearly species-specifi c
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作者 Yahya Kooch Neda Ghorbanzadeh +1 位作者 Samaneh Hajimirzaaghaee Markus Egli 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期1033-1049,共17页
Beech stands are considered part of the ancient forest ecosystems in the northern hemisphere.In mixed stands in beach forest ecosystems,the type of associated tree species can signifi cantly aff ect soil functions,but... Beech stands are considered part of the ancient forest ecosystems in the northern hemisphere.In mixed stands in beach forest ecosystems,the type of associated tree species can signifi cantly aff ect soil functions,but their infl uence on microbial activity,nutrient cycling and belowground properties is unknown.Here,we considered forest patches in northern Iran that are dominated by diff erent tree species:Fagus orientalis Lipsky,Quercus castaneifolia C.A.Mey.,Pterocarya fraxinifolia(Lam.),Tilia begonifolia Stev.,Zelkova carpinifolia Dippe,Acer cappadocicum Gled,Acer velutinum Boiss.,Fraxinus excelsior L.,Carpinus betulus L.,and Alnus subcordata C.A.Mey.For each forest patch–tree species,litter and soil samples(25×25×10 cm,100 of each)were analyzed for determine soil and litter properties and their relationship with tree species.The litter decomposition rate during a 1-year experiment was also determined.A PCA showed a clear diff erence between selected litter and soil characteristics among tree species.F.orientalis,Q.castaneifolia,P.fraxinifolia,T.begonifolia,Z.carpinifolia,A.cappadocicum,and A.velutinum enhanced soil microbial biomass of carbon,whereas patches with F.excelsior,C.betulus and A.subcordata had faster litter decomposition and enhanced biotic activities and C and N dynamics.Thus,soil function indicators were species-specifi c in the mixed beech forest.A.subcordata(a N-fi xing species),C.betulus and F.excelsior were main drivers of microbial activities related to nutrient cycling in the old-growth beech forest. 展开更多
关键词 Old-growth forest Deciduous tree species Soil fertility Microbial activities Carbon and nitrogen cycle
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<i>In Vitro</i>Anti-HIV Activity of Partially Purified Coumarin(s) Isolated from Fungal Endophyte, <i>Alternaria</i>Species of <i>Calophyllum inophyllum</i> 被引量:1
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作者 Melappa Govindappa Kavya C. Hemmanur +3 位作者 S. Nithin Chandrappa Chinna Poojari Gopalakrishna Bhat K. Channabasava 《Pharmacology & Pharmacy》 2015年第7期321-328,共8页
5 totally different endophytic fungal species were isolated from bark and leaf parts of Calophyllum inophyllum. Leaf part yielded Trichoderma harzianum and Alternaria species, whereas bark showed the presence of Fusar... 5 totally different endophytic fungal species were isolated from bark and leaf parts of Calophyllum inophyllum. Leaf part yielded Trichoderma harzianum and Alternaria species, whereas bark showed the presence of Fusarium species, Aspergillus species and unidentified fungi. Two solvents (hexane and methanol) were used for endophytic fungal extraction and the Alternaria species had shown the presence of coumarin whereas Trichoderma harzianum in methanol extract and Fusarium species in hexane extract had shown the coumarin(s) in all the four methods tested. The total coumarin yield was more in microwave assistance method, the methanol Alternaria species (3.941 ± 0.082) stood first, followed by hexane extract of Alternaria species (3.254 ± 0.082), Fusarium species (2.532 ± 0.082) and Trichoderma harzianum (2.294 ± 0.082), the plant extract showed 4.149 + 0.053. The methanol extract of Alternaria species inhibited the activity of HIV-Reverse Transcriptase (RT) (82.81 ± 1.0), integrase (98%) and protease (78) in maximum level followed by hexane extract of Alternaria species (71.12 ± 0.9, 89, 68), Fusarium species (63.92 ± 1.8, 67, 66) and Trichoderma harzianum (56.69 ± 0.9, 71, 63). The endophytic fungi Alternaria species inhibited all the three viral enzymes at maximum level and it was more than standard drug. However, in order to know possible anti-HIV, it is necessary to isolate active coumarin from the Alternaria species and the mechanism of action will be studied in future studies. 展开更多
关键词 ENDOPHYTES ALTERNARIA species HIV-RT INTEGRASE Protease Inhibitory activity
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Understanding of the structural evolution of catalysts and identification of active species during CO_(2) conversion
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作者 Li Li Fanpeng Chen +1 位作者 Bohang Zhao Yifu Yu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第4期17-30,共14页
Converting CO_(2) into value-added chemicals and fuels through various catalytic methods to lower the atmospheric CO_(2) concentration has been developed to be a crucial means to alleviate the energy shortage and amel... Converting CO_(2) into value-added chemicals and fuels through various catalytic methods to lower the atmospheric CO_(2) concentration has been developed to be a crucial means to alleviate the energy shortage and ameliorate the ever-fragile environment status. However, the complexity of the CO_(2) conversion reaction and the strong reduction conditions lead to the inevitable structural evolution, making it difficult for the prior design of suitable catalytic materials. Herein, to guide the rational design of efficient catalysts,we will be centered on the thermal, electro, and photo-induced structural evolution and active species identification during the CO_(2) conversion, including the in situ/operando characterization techniques monitoring the activation, steady, and deactivation stage of the catalysts as well as the inherent restructuring mechanism towards active species. Besides, the future challenges and opportunities on the merits of combining the structural evolution with the adsorbed intermediates recognized by ultra-fast spectroscopic techniques, simultaneously, the combination of theoretical simulation and the results of in situ experiments will also be addressed. This review can not only guide the identification of real active species, but also provide an approach to design the specific active species towards CO_(2) conversion, rather than only focusing on activity, for the purpose of practical industrial application. 展开更多
关键词 CO_(2) Structural evolution active species In situ OPERANDO
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Ethnobotanical and traditional uses, phytochemical constituents and biological activities of Eryngium species growing in Iran
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作者 Masoumeh Ghajarieh Sepanlou Mehran Mirabzadeh Ardakani +4 位作者 Mannan Hajimahmoodi Sima Sadrai Gholam-Reza Amin Naficeh Sadeghi Seyedeh Nargess Sadati Lamardi 《Traditional Medicine Research》 2019年第3期148-159,共12页
Objective: Eryngium with the 274 accepted species, is the largest genus of Apiaceae family which are distributed all over the world and have been used in traditional remedies to manage various ailments in different na... Objective: Eryngium with the 274 accepted species, is the largest genus of Apiaceae family which are distributed all over the world and have been used in traditional remedies to manage various ailments in different nations. Ten species of Eryngium have been identified in Iran including E. caeruleum M.B.(syn: E. caucasicum Trautv.), E. creticum Lam., E. bungei Boiss., E. billardieri F. Delaroche.(syn: E. kotschyi Boiss.), E. glomeratum Lam.(syn: E. parviflorum Sm.), E. bornumulleri Nab., E. pyramidale Boiss.& Husson., E. noeanum Boiss., E. wanaturi Woron.(syn: E. woronowii Bordz.), and E. thyrsoideum Boiss. The aim of the present research is to review pharmacological activity, and phytochemical constituents as well as ethnobotany and traditional uses of Iranian species of Eryngium. Materials and methods: Electronic databases including PubMed, Scopus, Science Direct (ISI Web of Knowledge) and Embase library were comprehensively searched for research on Eryngium. The search period was from 1966 to October 2018. The related articles were selected according to the inclusion and exclusion criterias in our study. Results: A total of 57 papers were enrolled in analyses. The findings showed that Iranian species of Eryngium, had a noticeable diverse of traditional medicinal uses and also broad range of pharmacological activities as well as various phytochemical compounds. Some remarkable biological and pharmacological activities of these species have been demonstrated in present scientific studies, including antimicrobial, cytotoxic and anticancer, anti-inflammatory, analgesic and antinociceptive activities as well as antioxidant, antidiabetic, anti-snake and anti-scorpion venom effects. Conclusion: Iranian Eryngium species have enormous potential for prospective preparation of herbal medicinal products and are good candidates for discovering new drugs. 展开更多
关键词 ERYNGIUM IRANIAN species PHARMACOLOGICAL activITIES PHYTOCHEMICAL compositions Traditional and ethnopharmacological uses
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Effect of Lanthanum (Ⅲ) on Reactive Oxygen Metabolism of Soybean Seedlings under Supplemental UV-B Irradiation 被引量:7
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作者 闫生荣 黄晓华 周青 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第3期352-358,共7页
The effect of lanthanum (Ⅲ) on reactive oxygen metabolism of soybean seedlings under elevated ultraviolet-B radiation(UV-B:280~320 nm)at 0.15 and 0.45 W·cm-2 levels respectively was studied through hydropon... The effect of lanthanum (Ⅲ) on reactive oxygen metabolism of soybean seedlings under elevated ultraviolet-B radiation(UV-B:280~320 nm)at 0.15 and 0.45 W·cm-2 levels respectively was studied through hydroponics in the laboratory.Plasmolemma permeability and contents of malonadialdehyde(MDA),hydrogen peroxide(H2O2),and proline gradually increased during the imposition of UV-B radiation and subsequently decreased during recovery from UV-B stress.The dynamic tendency of catalase(CAT)activity was similar to that of the above four indices.The activity of peroxidase(POD)initially increased,then remained at a high level,and finally dropped steeply when soybean seedlings were exposed to a low dosage of UV-B radiation.However,POD activity rose throughout and declined slightly on the eleventh day when soybean seedlings were stressed by a high dosage.With the addition of La (Ⅲ) of 20 mg·L-1,the rising tendency of plasmolemma permeability and contents of MDA,H2O2,and proline were slowed down during the stress period,whereas the declining speed was accelerated during the recovery period.The activities of CAT and POD were higher than those without La (Ⅲ) in all experiments.It suggested that the regulative effect of La (Ⅲ) on antioxidant enzymes such as CAT and POD could strengthen their capacities to scavenge reactive oxygen species(ROS),decrease contents of MDA and proline,and maintain normal plasmolemma permeability.Further more,the protective potential of La (Ⅲ) was better under low UV-B radiation than under a high one. 展开更多
关键词 lanthanum (Ⅲ) ultraviolet-B radiation soybean seedlings metabolism of reactive oxygen species CATactivity POD activity
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In vitro antiplasmodial effect of ethanolic extracts of traditional medicinal plant Ocimum species against Plasmodium falciparum 被引量:3
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作者 Samuel Jacob Inbaneson Sundaram Ravikumar Palavesam Suganthi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第2期103-106,共4页
Objective:To identify the possible antiplasmodial compounds from leaf,stem,root and flower extracts of Ocimum canum(O.canum),Ocimum sanctum(O.sanctum) and Ocimum basilicum (O.basilicum).Methods:The O.canum,O.san... Objective:To identify the possible antiplasmodial compounds from leaf,stem,root and flower extracts of Ocimum canum(O.canum),Ocimum sanctum(O.sanctum) and Ocimum basilicum (O.basilicum).Methods:The O.canum,O.sanctum and O.basilicum were collected from Ramanalhapuram District,Tamil Nadu and the extraction was carried out in ethanol.The filter sterilized extracts(100,30,23,12.5,6.23 and 3.125μg/mL) of leaf,stem,root and flower extracts of O.canum,O.sanctum and O.basilicum were tested for antiplasmodial activity against Plasmodium falciparum(P.falciparum).The potential extracts were also tested for their phytochemical constituents.Results:The leaf extract of O.sanctum showed excellent antiplasmodial activity(IC<sub>50</sub> 3538μg/mL) followed by leaf extract of O.basilicum(IC<sub>50</sub> 4341μg/mL). The leaf extract of O.canum,root extracts of O.sanctum and O.basilicum,the stem and flower extracts of all the three tested Ocimum species showed IC<sub>50</sub> values between 50 and 100μg/mL Statistical analysis reveals that,significant antiplasmodial activity(P【0.01) was observed between the concentrations and time of exposure.The chemical injury to erythrocytes was also carried out and it shows that,there were no morphological changes in erythrocytes by the ethanolic extract of O.canum,O.sanctum and O.basilicum.The in vitro antiplasmodial activity might be due to the presence of alkaloids,glycosides,flavonoids,phenols,saponins,triterpenoids,proteins,resins, steroids and tannins in the ethanolic extracts of tested plants.Conclusions:The ethanolic leaf extracts of O.sanctum possess lead compounds for the development of antiplasmodial drugs. 展开更多
关键词 ANTIPLASMODIAL activity IC50 Phytochemicals PLASMODIUM FALCIPARUM OCIMUM species
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