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Gold nanoparticles as dehydrogenase mimicking nanozymes for estradiol degradation

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Chinese Chemical Letters 2019年第9期30卷 1655-1658页

作者： Zijie Zhang leslie M. Bragg Mark R. Servos Juewen Liu Department of Chemistry Waterloo Institute for Nanotechnology University of Waterloo Waterloo Ontario N2L 3G1 Canada Department of Biology University of Waterloo Waterloo Ontario N2L 3G1 Canada

nanozyme catalysis has been mainly focused on a few chromogenic and fluorogenic substrates, while environmentally and biologically important compounds need to be tested to advance the field. In this work, we studied oxidation of estradiol(E2) in the presence of various nanomaterials including gold nanoparticles(AunPs), nanoceria(CeO2), Fe3O4, Fe2O3, MnO2 and Mn2O3, and found that AunPs had a dehydrogenase-mimicking activity to convert E2 to estrone(E1). This conversion was monitored using HPLC. The reaction was faster at higher pH and reached saturation at pH 8. Smaller AunPs had a higher catalytic efficiency and 5 nm AunPs were 4.8-fold faster than 13 nm at the same total surface area. Finally,we tried 17α-ethinylestradiol(EE2) as a substrate and found that 5 nm AunPs can catalyze EE2 oxidation in the presence of H2O2. This work indicated that some nanomaterials can affect environmentally important hormones via oxidation reactions, and this study has expanded the scope of substrate of nanozymes.

关键词： nanozymes Estradiol Gold nanoparticles Catalysis Environment HPLC

Diversity of Arbuscular Mycorrhizal Fungi Species Associated with Soybean (Glycine max L. Merill) in Benin

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American Journal of Plant Sciences 2022年第5期13卷 686-701页

作者： Howell B. Houngnandan Appolinaire Adandonon Trévis S. B. Adoho leslie D. R. Bossou Adélaïde H. Fagnibo Oslo S. Gangnon Moriaque Akplo Charlotte M. Zoundji Félix kouèlo Adolphe Zeze Pascal Houngnandan Laboratoire des Sciences Végétale Horticole et Forestière (LaSVHF) Université Nationale d’Agriculture (UNA) Kétou République du Bénin Laboratoire de Microbiologie des Sols et d’Ecologie Microbienne Faculté des Sciences Agronomiques de l’Université d’Abomey-Calavi (UAC) Abomey-Calavi République du Bénin Laboratoire de Biotechnologies Végétale et Microbienne Unité Mixte de Recherche et d’Innovation en Sciences Agronomiques et Génie Rural Institut National Polytechnique Felix Houphou&#235 t-Boigny (InPHB C&#244 te d’Ivoire) Yamoussoukro C&#244 te d’Ivoire Ecole de Gestion et de Production Vegetale et Semenciere (EGPVS) Université Nationale d’Agriculture (UNA) Kétou République du Bénin

Arbuscular Mycorrhizal Fungi (AMFs) could be used to sustainably improve crop yields. The present study evaluated the diversity of AMF species associated with soybean (Glycine max L. Merill) in main soybean-producing areas in Benin. Composite soil samples from 13 production areas at a rate of 04 villages per production areas were collected. A spore trapping device was set up to reveal the diversity of spores. The physical and chemical properties of the soils, the frequency and intensity of mycorrhization of roots, and the diversity of AMF spores were determined in the soil samples following trapping. As result, eight morphotypes belonging to four genera: Glomus, Acaulospora Gigaspora and Disversispora and three families: Diversisporales, Glomérales and Paraglomérales were observed. An important variability of spore densities was observed from one production areas to another with a higher abundance in the production areas of Copargo estimated at 3584 spores/100g soil. The biological diversity indexes as Shannon (0.0311), Simpson (0.0204) and Hill (0.0235), varied significantly (p ne production areas to another. There was significant correlation between the parameters studied, particularly between the physico-chemical parameters of the soils and between the physico-chemical parameters and the biological diversity indexes. For the mycorrhization parameters, the mycorhization frequencies did not vary from one production areas to another, unlike the intensities, which significantly varied from one production areas to another (2.31% to 24.62%). Finally, this study revealed that the physico-chemical parameters of the soils had an influence on the other parameters studied. Moreover, there were an abundance and a significant diversification of AMFs associated with soybean in the different production areas, which are influenced by certain physico-chemical soil parameters.

关键词： Arbuscular Mycorrhizal Fungi (AMFs) Soybean Spore Density Diversity

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npj Computational Materials 2021年第1期7卷 1474-1480页

作者： Iaroslav Gaponenko loïc Musy neus Domingo nicolas Stucki Albert Verdaguer nazanin Bassiri-Gharb Patrycja Paruch Department of Quantum Matter Physics University of GenevaGenevaSwitzerland G.W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGAUSA Catalan Institute of nanoscience and nanotechnology(ICn2) CSIC and BISTCampus UABBarcelonaSpain University of Applied Sciences and Arts Western Switzerland(HES-SO/HEPIA) GenevaSwitzerland Institut de Ciència de Materials de Barcelona(ICMAB) CSICCampus UABBarcelonaSpain School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGAUSA

Electrochemical phenomena in ferroelectrics are of particular interest for catalysis and sensing applications,with recent studies highlighting the combined role of the ferroelectric polarisation,applied surface voltage and overall switching ***,we present a systematic kelvin probe microscopy study of the effect of relative humidity and polarisation switching history on the surface charge dissipation in ferroelectric Pb(Zr_(0.2)Ti_(0.8))O_(3)thin *** analyse the interaction of surface charges with ferroelectric domains through the framework of physically constrained unsupervised machine learning matrix factorisation,Dictionary Learning,and reveal a complex interplay of voltage-mediated physical processes underlying the observed signal *** insight into the observed behaviours is given by a Fitzhugh–nagumo reaction–diffusion model,highlighting the lateral spread and charge passivation process contributors within the Dictionary Learning analysis.

关键词： ferroelectric charge film

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学校改进中教师领导研究述评

教育学报 2010年第3期6卷 35-40页

作者：张佳伟卢乃桂华南师范大学广州510631 香港中文大学

在学校改进的研究中,教师领导已愈来愈成为重要的研究领域。目前学校改进中教师领导的研究集中于对行使领导力的教师——"领袖教师"的研究,围绕领袖教师在学校改进中的角色、能力、发展以及与他人的关系而展开。整体而言,现有的研究存... 详细信息

在学校改进的研究中,教师领导已愈来愈成为重要的研究领域。目前学校改进中教师领导的研究集中于对行使领导力的教师——"领袖教师"的研究,围绕领袖教师在学校改进中的角色、能力、发展以及与他人的关系而展开。整体而言,现有的研究存在以下的特点:(1)领袖教师自身的专业发展是研究的核心;(2)整全式的研究策略;(3)领袖教师与情境的关系研究还较为缺乏。

关键词：学校改进教师领导领袖教师

Antibiotic resistance assessment in bacteria isolated in migratory Passeriformes transiting through the Metaponto territory(Basilicata,Italy)

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Avian Research 2017年第4期8卷 255-265页

作者： Maria Foti Antonietta Mascetti Vittorio Fisichella Egidio Fulco Bianca Maria Orlandella Francesco lo Piccolo Department of Veterinary Sciences University of MessinaPolo Universitario dell’Annunziata98168 MessinaItaly naturalistic Study Milvus Pantano Street 13485010 PignolaPZItaly

Background: Wild birds are considered to be reservoirs of human enteric pathogens and vectors of antimicrobial resistance dissemination in the *** their annual migration,they play a potential role in the epidemiology of human associated *** aim of this study was to investigate the frequency of isolation and antimicrobial susceptibility profiles of microorganisms found in the cloaca of common European ***: One hundred and twenty-one cloacal swabs were collected during a monitoring program of migratory birds in the Forest Reserve for Protection "Metaponto"(Basilicata,Italy).All samples were cultured using standard bacteriological methods and antibiotic susceptibility testing(agar disk diffusion test) of isolated strains was ***: The bacteriological analysis produced 122 strains belonging to 18 different *** most commonly isolated species were Enterobacter cloacae and Providencia rettgeri(21 strains,17.2%).Potentially pathogenic species including klebsiella pneumoniae,Serratia marcescens and Pseudomonas *** also been *** showed significant frequencies of antimicrobial *** highest frequency of resistance was observed against amoxicillin(n = 79,64.8%);ampicillin(n = 77,63.1%);rifampicin(n Thirty-one strains(25.4%) showed resistance to imipenem a= 75,61.5%);amoxicillin–clavulanic acid(n nd 8(6.6%) to meropenem.= 66,54.1%).Conclusions: Migratory birds play an important role in the ecology,circulation and dissemination of potentially pathogenic antimicrobial resistant *** can therefore be considered sentinel species and environmental health *** results suggest that the integration of epidemiological surveillance networks during ringing campaigns of wild species can be an effective tool to study this phenomenon.

关键词： Passeriformes Cloacal swabs Bacteriological test Antimicrobial resistance

Generalized food-deceptive orchid species flower earlier and occur at lower altitudes than rewarding ones

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Journal of Plant Ecology 2010年第4期3卷 243-250页

作者： loıc Pellissier Pascal Vittoz Antonina Ingrid Internicola Luc Daniel Bienvenu Gigord Department of Ecology and Evolution University of LausanneBiophoreCH-1015 LausanneSwitzerland Faculty of Geosciences and Environment University of LausanneBiophoreCH-1015 LausanneSwitzerland Conservatoire Botanique national de Mascarin 2 rue du Pe`re GeorgesLes Colimac xons97436 Saint-LeuLa Re´unionFrance Present address:Department of Biological Sciences 2500 University Drive N.W.University of CalgaryCalgary ABAlbertaCanada T2N 1N4

Aims Food-deceptive pollination,in which plants do not offer any food reward to their pollinators,is common within the *** food-deceptive orchids are poorer competitors for pollinator visitation than rewarding orchids,their occurrence in a given habitat may be more constrained than that of rewarding *** particular,the success of deceptive orchids strongly relies on several biotic factors such as interactions with co-flowering rewarding species and pollinators,which may vary with altitude and over *** study compares generalized food-deceptive(*** sexually deceptive)and rewarding orchids to test whether(i)deceptive orchids flower earlier compared to their rewarding counterparts and whether(ii)the relative occurrence of deceptive orchids decreases with increasing *** To compare the flowering phenology of rewarding and deceptive orchids,we analysed data compiled from the literature at the species level over the occidental Palaearctic *** flowering phenology can be constrained by the latitudinal distribution of the species and by their phylogenetic relationships,we accounted for these factors in our *** compare the altitudinal distribution of rewarding and deceptive orchids,we used field observations made over the entire Swiss territory and over two Swiss mountain *** Findings We found that deceptive orchid species start flowering earlier than rewarding orchids do,which is in accordance with the hypotheses of exploitation of naive pollinators and/or avoidance of competition with rewarding co-occurring ***,the relative frequency of deceptive orchids decreases with altitude,suggesting that deception may be less profitable at high compared to low altitude.

关键词： altitude timing of flowering food-deception European orchids Orchidaceae biogeography

Industrial Centric node localization and Pollution Prediction Using Hybrid Swarm Techniques

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Computer Systems Science & Engineering 2022年第8期42卷 545-560页

作者： R.Saravana Ram M.Vinoth kumar n.krishnamoorthy A.Baseera D.Mansoor Hussain n.Susila Department of Electronics and Communication Engineering Anna UniversityUniversity College of Engineering DindigulDindigul624622India Department of Computer Science and Engineering Anna UniversityUniversity College of Engineering DindigulDindigul624622India Department of Computer Science and Engineering Kongu Engineering CollegePerundurai638060India School of Computing Science and Engineering VIT Bhopal UniversityBhopal466114India Department of Computer Science and Engineering Sri Krishna College of Engineering and TechnologyCoimbatore641008India Department of Information Technology Sri Krishna College of Engineering and TechnologyCoimbatore641008India

Major fields such as military applications,medical fields,weather forecasting,and environmental applications use wireless sensor networks for major computing *** play a vital role in emerging technologies of the 20th *** of sensors in needed locations is a very serious *** environment is home to every living being in the *** growth of industries after the industrial revolution increased pollution across the *** to recent uncontrolled growth and development,sensors to measure pollution levels across industries and surroundings are *** interesting and challenging task is choosing the place to fit the *** meta-heuristic techniques have been introduced in node *** intelligent algorithms have proven their efficiency in many studies on localization *** this article,we introduce an industrial-centric approach to solve the problem of node localization in the sensor ***,our work aims at selecting industrial areas in the sensed *** use random forest regression methodology to select the polluted ***,the elephant herding algorithm is used in sensor node *** two algorithms are combined to produce the best standard result in localizing the sensor *** check the proposed performance,experiments are conducted with data from the kDD Cup 2018,which contain the name of 35 stations with concentrations of air pollutants such as PM,SO_(2),CO,nO_(2),and O_(3).These data are normalized and tested with *** results are comparatively analyzed with other swarm intelligence algorithms such as the elephant herding algorithm,particle swarm optimization,and machine learning algorithms such as decision tree regression and multi-layer *** can indicate our proposed algorithm can suggest more meaningful locations for localizing the sensors in the *** proposed method achieves a lower root mean square value with 0.06 to 0.08 for lo

关键词： Wireless sensor networks node localization industrial-centric approach random forest regression elephant herding optimization swarm intelligence pollution

Chemical and Sr-nd compositions and ^(40)Ar/^(39)Ar ages of nW-trending dolerite dikes of Burkina Faso: Evidence for a Mesoproterozoic magmatism in the West African Craton

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Geoscience Frontiers 2018年第6期9卷 1957-1980页

作者： Boukare Tapsoba Ching-Hua lo Urbain Wenmenga Yoshiyuki Iizuka Sun-Lin Chung Gregory Shellnutt Department of Geosciences National Taiwan University UFR-SVT Département de Géologie Université Pr.Joseph Ki-Zerbo de Ouagadougou Institute of Earth Sciences Academia Sinica Department of Earth Sciences National Taiwan Normal University

The Paleoproterozoic basement of the northeastern part of the Leo-Man craton is intruded by generally nW-trending dikes. These regional scale dikes extend over 1000 km in Burkina Faso, Mali and niger. We present chemical and Sr-nd isotope compositions, as well as 40 Ar/39 Ar ages of these dikes with the following strikes n98°-n112°, and n114°-n124° in nE Burkina Faso. Field relationships show that the dikes are posterior to all other rock types dated between 2.26 Ga and 2.0 Ga. Chemical data indicate that the dikes are continental flood basalts and composed of low-Ti(TiO2 ≤ 2 wt.%) sub-alkaline basalts and andesites. They exhibit a minor negative Europium anomaly(0.86-0.99) and slightly fractionated REE patterns((La/Yb)_n= 2.5-9.1; Yb_n = 9.5-19.9). The ratios of Th/Ta(1.3-11.4) and Ce/Pb(5.2-58.5)suggest a varying crustal assimilation of the dike magmas during ascent in the continental crust for all studied samples. Calculated P-T conditions indicate that the magma reached temperatures of 1285 ℃(calculated from olivine compositions) and pressures of 6.9 kbar(calculated for pyroxene minerals).Calculated initial 87 Sr/86 Sr(0.70040-0.70260) and ε_(nd)(t)=+2.1 to-3.5 at 1575 Ma,also point to a crustal contamination with the most primitive samples showing T_(DM) values of 1946 Ma and 2154 Ma. The low values of La/Ba(nd nb/La(ntrast with the low Th/nb(nd suggest a lithospheric mantle or subduction-modified mantle as possible source for the dikes. Sr-nd data, Mg# and nbTa-Zr-Y-Th-Tb-Yb compositions further suggest that the most primitive samples were emplaced in a none orogenic setting and their magmas were subjected to variable crustal contaminations. Literature and the present whole rock 40 Ar/39 Ar age determinations show that the dikes were emplaced during a widespread Mesoproterozoic magmatism between 1.6 Ga and 1.2 Ga, and were affected by a thermal event causing the argon systematics resetting, best constrained by the date of sample kk1(123

关键词： Mafic dike swarm Depleted mantle Mesoproterozoic Continental tholeiites nuna West African Craton

Exploring system architectures in AADL via Polychrony and SynDEx

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Frontiers of Computer Science 2013年第5期7卷 627-649页

作者： Huafeng YU Yue MA Thierry GAUTIER loc BESnARD Jean-Pierre TALPIn Paul Le GUERnIC Yves SOREL InRIA Rennes-Bretagne Atlantique 263 av. du Général LeclercRennes 35042 France IRISA/CnRS 263 av. du Général LeclercRennes 35042 France InRIA Paris-Rocquencourt Domaine de VoluceauBP 105Le Chesnay Cedex 78153 France

Architecture analysis&design language(AADL)has been increasingly adopted in the design of embedded systems,and corresponding scheduling and formal verification have been well ***,little work takes code distribution and architecture exploration into account,particularly considering clock constraints,for distributed multi-processor *** this paper,we present an overview of our approach to handle these concerns,together with the associated toolchain,***,in order to avoid semantic ambiguities of AADL,the polychronous/multiclock semantics of AADL,based on a polychronous model of computation,is *** synthesis is then carried out in Polychrony,which bridges the gap between the polychronous semantics and the synchronous semantics of *** same timing semantics is always preserved in order to ensure the correctness of the transformations between diferent *** distribution and corresponding scheduling is carried out on the obtained SynDEx model in the last step,which enables the exploration of architectures originally specified in *** contribution provides a fast yet efcient architecture exploration approach for the design of distributed real-time and embedded *** avionic case study is used here to illustrate our approach.

关键词： Polychrony Signal AADL SynDEx architecture exploration modeling timing analysis scheduling distribution