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Effects of the availability of floral resources and neighboring plants on nectar robbery in a specialized pollination system

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Current Zoology 2022年第5期68卷 541-548页

作者： Júlia Mendonça Almeida Caio César Corrêa Missagia Maria Alice Santos Alves Graduação Instituto de BiociênciasUniversidade Federal do Estado do Rio de Janeiro(UNIRIO)CEPAvenida Pasteur458Rio de Janeiro 22290-240Brazil Departamento de Ecologia Programa de Pós-Graduação em Ecologia e EvoluçãoInstituto de Biologia Roberto Alcantara Gomes(IBRAG)Laboratório de Ecologia de Aves e ComportamentoUniversidade do Estado do Rio de Janeiro(UERJ)Rua São Francisco Xavier524 Rio de JaneiroRJCEPRio de Janeiro 20550-011Brazil Departamento de Ecologia IBRAGLaboratório de Ecologia de Aves UERJ.Rua São Francisco Xavier524 Rio de JaneiroRJCEPRio de Janeiro 20550-011Brazil

Many plants pollinated by nectar-foraging animals have to maintain a balance between legitimate visitor attraction strategies and mechanisms that minimize illegitimate *** study investigated how floral display and neighboring species composition influences nectar robbing by hummingbirds in the tropical ornithophilous herb Heliconia *** tested the role of inflorescence display,flower abundance,and neighboring species in the reduction of nectar robbing in *** results indicate that nectar robbing hummingbird activity was higher in moderately large inflorescence displays and that the frequency of nectar robbing in *** decreases with increased flower abundance and the presence of neighboring plant *** non-ornithophilous plants decreased the frequency of nectar robbing in *** flowers to a greater extent than ornithophilous *** results suggest that nectar robbing hummingbirds are attracted to similar conditions that attract legitimate visitors and that spatial aggregation and mixed-species displays may represent a mechanism to dilute nectar robbing effects at an individual level.

关键词： Brazilian Atlantic forest density floral antagonists Heliconiaceae

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Elevated nitric oxide and 3',5' cyclic guanosine monophosphate levels in patients with alcoholic cirrhosis

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World Journal of Gastroenterology 2008年第2期14卷 236-242页

作者： Cíntia Siqueira Miguel Carneiro de Moura Ana Júlia pedro Paula Rocha Center of Gastroenterology Institute of Molecular Medicine School of Medicine University of Lisbon Portugal Department of Medicine Ⅱ University Hospital of Santa MariaLisbonPortugal

AIM: To evaluate whether serum levels of nitric oxide (NO ·) and plasma levels of cyclic guanosine monophosphate (cGMP) and total glutathione (GSH) are altered in patients with alcoholic cirrhosis and to examine their correlation with the severity of liver ***: Twenty-six patients with alcoholic liver cirrhosis were studied. Serum levels of NO · and plasma levels of cGMP and GSH were measured in 7 patients with compensated alcoholic cirrhosis (Child-Pugh A) and 19 patients with advanced cirrhosis (Child-Pugh B and C). The model for end-stage liver disease (MELD) score was evaluated. Sixteen healthy volunteers served as controls. Liver enzymes and creatinine levels were also ***: NO · and cGMP levels were higher in patients with Child-Pugh B and C cirrhosis than in Child-Pugh A cirrhosis or controls (NO ·: 21.70 ± 8.07 vs 11.70 ± 2.74; 21.70 ± 8.07 vs 7.26 ± 2.47 μmol/L, respectively; P pectively; P pectively; P pensated patients with higher levels of NO ·and cGMP and lower GSH levels than in compensated and control patients. Altered mediator levels in decompensated patients may influence the hemodynamic changes in and progression of liver disease.

关键词： Oxidative stress Nitric oxide Alcoholic cirrhosis Fibrosis Model for end-stage liver disease

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Optimization and evaluation of fish oil rnicrocapsules

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Particuology 2016年第6期14卷 162-168页

作者： Hui Liu lia nyan Wang Tingyuan Yang Guifeng Zhang Jian Huang Jing Sun Junsheng Huo Division of Food Science & Technology National Institute for Nutrition and Health Chinese Center for Disease Control and Prevention Beijing 100050China National Key Lab of Biochemical Engineering Institute of Process Engineering Chinese Academy of Science Beifing 100190 China

Fish oil microcapsules were prepared using two natural polysaccharides, alginate and chitosan, as the wall materials. A response surface methodology （RSM） was used to optimize the conditions for fish oil encapsulation efficiency （FOEE）. The FOEE was investigated with respect to three key-variables in the RSM： ratio of inner oil phase to aqueous phase （X1 w/w）; concentration of the aqueous phase （X2, wt%）; and ratio of the aqueous phase to outer oil phase （X3, v/v）. The optimal formulation obtained from the RSM model, i.e., 2.7：1 （X1）, 1.6 wt% （X2）, and 11.5：1 （X3）, gave a FOEE of 28%. The model was validated and the fish oil microcapsules prepared under the optimized conditions were characterized in terms of particle size, polydispersity index （PDI）, zeta potential, surface morphology, and in vitro release. The average droplet size, PDI, and zeta potential were 915 nm, 0.038, and ＋5.2 mV, respectively. The fish oil microcapsules were highly uniform microspheres, and had an accumulative release rate of 77.7% in 270 min in a gastrointestinal model, indicating their potential as an alternative carrier for the controlled release of fish oil. In conclusion, formulating optimal microencapsulation conditions by the RSM can be applied to the microencapsulation of various oil-soluble nutrients for food applications.

关键词： Optimization Microencapsulation Fish oil Evaluation Response surface methodology

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含碳铁泥基催化剂活化H_(2)O_(2)处理亚甲基蓝废水

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工业水处理 2024年第2期44卷 125-132页

作者：王俩吴霜程小双梁澜李宁陈冠益侯立安天津大学环境科学与工程学院天津300350 中环保水务投资有限公司北京100082 天津商业大学机械工程学院天津300134

利用铁泥基催化剂构建类Fenton体系可实现污水厂废弃铁泥的资源化利用。热解温度可调控催化剂表面金属和非金属位点组成,影响其对过氧化氢(H_(2)O_(2))的活化效果。对不同热解温度(400~700℃)下制备的催化剂进行形貌、组成、结构和活性... 详细信息

利用铁泥基催化剂构建类Fenton体系可实现污水厂废弃铁泥的资源化利用。热解温度可调控催化剂表面金属和非金属位点组成,影响其对过氧化氢(H_(2)O_(2))的活化效果。对不同热解温度(400~700℃)下制备的催化剂进行形貌、组成、结构和活性等方面的测试。研究发现,700℃下制备的催化剂活化H_(2)O_(2),在100 min内对亚甲基蓝(MB)降解率达92.0%。当热解温度在400~700℃范围内增大时,催化剂比表面积和C含量均增大。机理探究表明,催化剂表面的Fe0、C==C/C—C和C==O活性位点对活化H_(2)O_(2)发挥重要作用,有利于促进亚甲基蓝降解。此外,铁泥基催化剂/H_(2)O_(2)体系中羟基自由基(·OH)和单线态氧(^(1)O_(2))是主要活性物种,超氧自由基(O_(2)^(·-))发挥作用较小。

关键词：废弃铁泥类Fenton 染料废水

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Night and day at the beach: Relating social life to location and infrastructure in a Brazilian city

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Frontiers of Architectural Research 2022年第6期11卷 1177-1192页

作者： Lucy Donegan Gabriel de Oliveira Madruga Natália Vale Carneiro Departamento de Arquitetura e Urbanismo Federal University of ParaíbaJoão PessoaParaíbaBrazil

Brazilian city beaches are public spaces favoring citizens *** studies relate built form and infrastructure with urban vitality and coastal studies underline uses as important for beach management,yet few researches relate form and infrastructure with beach *** daily life as essential for public spaces and that spatial form relates with uses,this paper assesses time-based relationships between built and natural physical attributes and social life on the beaches of João pessoa,a coastal city in North-east *** attributes are investigated at city scale-beach type,street network centrality and topography-and seafront scale-land uses,public/private interfaces,public infrastructure,beach sections and water *** social life was surveyed online,enquiring peoples’beach choice,visiting time and place,activities and *** and street network follow topography and help configure shore and promenade for different *** central beaches have diverse land uses,well-equipped promenades and lighting and were popular night and day,while less central beaches had less infrastructure and were visited only by *** highlight how physical attributes facilitate uses and,together with peoples’evaluation,can inform urban beach design and planning.

关键词： Public space Social life Built environment Beaches Public infrastructure

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Inside the Light Boojums: a Journey to the Land of Boundary Defects

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Analysis in Theory and Applications 2020年第2期36卷 128-160页

作者： Stan Alama lia Bronsard petru Mironescu Department of Mathematics&Statistics McMaster UniversityHamiltonOntarioL8S 4K1 Canada Universit'e de Lyon CNRS UMR 5208Universit´e Lyon 1Institut Camille Jordan43 blvd.du 11 Novembre 1918F-69622 Villeurbanne CedexFrance

We consider minimizers of the energy Eε(u)=:∫Ω[1/2|■u|^2+1/4ε2(|u|^2-1)^2]dx+1/2ε^s∫■ΩW(u,g)ds,u:Ω→■,0-cosα)^2,0 详细信息

We consider minimizers of the energy Eε(u)=:∫Ω[1/2|■u|^2+1/4ε2(|u|^2-1)^2]dx+1/2ε^s∫■ΩW(u,g)ds,u:Ω→■,0-cosα)^2,0perture,centered at the normal vector to the *** the regime where s[α^2+(π-α)^2]<π^2/2,any limiting map u*:Ω→S^1 has only boundary vortices,where its phase jumps by either 2α(light boojums)or 2(π-α)(heavy boojums).Our main result is the fine-scale description of the light boojums.

关键词： Nematics thin-film limit Ginzburg-Landau type energy weak anchoring boundary vortices asymptotic profile

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Self-assembled peG-b-PDPA-b-PGEM copolymer nanoparticles as protein antigen delivery vehicles to dendritic cells:preparation,characterization and cellular uptake

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Regenerative Biomaterials 2017年第1期4卷 11-20页

作者： Pan Li Junhui Zhou Pingsheng Huang Chuangnian Zhang Weiwei Wang Chen lia Deling Kong Tianjin Key Laboratory of Biomaterial Research Institute of Biomedical EngineeringChinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300192China School of Chemical Engineering and Technology Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin UniversityTianjin 300072China

Antigen uptake by dendritic cells(DCs)is a key step for initiating antigen-specific T cell *** the present study,novel synthetic polymeric nanoparticles were prepared as antigen delivery vehicles to improve the antigen uptake by ***-defined cationic and acid-responsive copolymers,monomethoxy poly(ethylene glycol)-block-poly(2-(diisopropyl amino)ethyl methacrylate)-block-poly(2-(guanidyl)ethyl methacrylate)(mpeG-b-PDPA-b-PGEM,peDG)were synthesized by reversible addition-fragmentation chain transfer polymerization of 2-(diisopropylamino)ethyl methacrylate and N-(tert-butoxycarbonyl)amino ethyl methacrylate monomers,followed by deprotection of tert-butyl protective groups and guanidinylation of obtained primary amines.1H NMR,13C NMR and GPC results indicated the successful synthesis of well-defined peDG *** copolymers could self-assemble into nanoparticles in aqueous solution,which were of cationic surface charges and showed acid-triggered disassembly contributed by PGEM and PDPA moieties,***,peDG nanoparticles could effectively condense with negatively charged model antigen ovalbumin(OVA)to form OVA/peDG nanoparticle formulations with no influence on its secondary and tertiary structures demonstrating by far-UV circular dichroism and UV-vis *** vitro antigen cellular uptake by bone marrow DCs(BMDCs)indicated using peDG nanoparticles as antigen delivery vehicles could significantly improve the antigen uptake efficiency of OVA compared with free OVA or the commercialized Alum ***,as the surface cationic charges of OVA/peDG nanoparticle formulations reduced,the uptake efficiency decreased ***,our work suggests that guanidinylated,cationic and acid-responsive peDG nanoparticles represent a new kind of promising antigen delivery vehicle to DCs and hold great potential to serve as immunoadjuvants in the development of vaccines.

关键词： guanidyl synthetic copolymer nanoparticles antigen delivery dendritic cells

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How reliable is the ReaxFF potential for describing the structure of alkanethiols on gold?A molecular dynamics study

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International Journal of Modeling, Simulation, and Scientific Computing 2014年第S1期5卷 137-145页

作者： Velachi Vasumathi José Luis Cagide Fajin Maria Natália Dias Soeiro Cordeiro REQUIMTE Department of Chemistry and Biochemistry University of PortoRua do Campo Alegre 6874168-007PortoPortugal

The structures of self-assembled monolayers(Sams)of short(methyl)and long(hexyl)chain alkyl thiols on the clean gold(111)surface were modeled using for the Au–S interactions either the reactive ReaxFF potential or the well-known nonreactive Morse potential,while for the Au–Au interactions either the ReaxFF potential or an embeddedatom method(Eam).Analysis of the molecular dynamics(MD)trajectories of possible Sam structures suggests that disordering of interfacial Au atoms is definitely driven by the gold–sulphur *** MD results reveal a novel structure where two methanethiol molecules are bound to a gold adatom that has been lifted from the surface at 300 K,and the same kind of RS–Au–SR motif was also observed for hexanethiol at 600 K but not at 300 *** is more,the above motif is only observed for the reactive ReaxFF ***,these results are in clear agreement with recent experiments and more costly first principles-based MD *** findings strongly support the use of reactive potentials such as ReaxFF for gathering an accurate description of Au–S interactions in inexpensive classical MD simulations.

关键词： Reactive potential alkanethiols self-assembled monolayers gold surface MD simulations

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A survey of executive compensation contracts in China's listed companies

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China Journal of Accounting Research 2013年第3期6卷 211-231页

作者： Yubo lia Fang Lou Jiwei Wang Hongqi Yuan Sydney Institute of Language and Commerce Shanghai University School of Economics Shanghai University of Finance and Economics School of Accountancy Singapore Management University School of Management Fudan University

We analyze 228 executive compensation contracts voluntarily disclosed by Chinese listed firms and find that central-government-controlled companies disclose more information in executive compensation contracts than localgovernment-controlled and non-government-controlled companies. Cashbased payments are the main form of executive compensation, whereas equity-based payments are seldom used by Chinese listed companies. On average, there are no significant differences in the value of basic salaries and performance-based compensation in executive compensation ***, compared with their counterparts in non-government-controlled companies, executives in government-controlled companies are given more incentive compensation. Accounting earnings are typically used in executive compensation contracts, with few firms using stock returns to evaluate their executives. However, the use of non-financial measures has increased significantly since 2007.

关键词： Executive compensation Voluntary disclosure Incentives performance measures

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Hydrocarbons in particulate samples from wildfire events in central Portugal in summer 2010

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Journal of Environmental Sciences 2017年第3期29卷 122-131页

作者： Ana Vicente Ana Calvo Ana P.Fernandes Teresa Nunes Cristina Monteiro Casimiro Pio Célia Alves Centre for Environmental and Marine Studies (CESam) Department of EnvironmentUniversity of Aveiro Department of Physics IMARENABUniversity of León

In summer 2010, twenty eight （14 PM=2.5 samples plus 14 samples PM2.5-10） smoke samples were collected during wildfires that occurred in central Portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse （PM=2.5-10） and fine （PM2.5） smoke samples. The carbonaceous content （elemental and organic carbon） of particulate matter was analysed by a thermal-optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatog- raphy into three different classes of organic compounds （aliphatics, polycyclic aromatic hydrocarbons （PAHs） and carbonyl compounds）. The organic speciation was performed by gas chromatography-mass spectrometry （GC-MS）. Emissions were dominated by the fine particles, which represented around 92% of the PM10. A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon （OC/EC） ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone 6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between OC and both aliphatic and PAH compounds. Pyrogenic processes, thermal release of biogenic com- pounds and secondary processing accounted for 97% of the apportioned PM2.5 levels.

关键词： WildfiresOrganic carbonOrganic compoundsBiomarkersParticulate matterPortugal

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