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Evaluation of bias on the assessment of diet breadth of herbivorous insects using molecular methods

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Insect Science 2017年第2期24卷 194-209页

作者： Gissela de la Cadena Anna Papadopoulou Jean-michel Maes Jesus Gomez-Zurita Animal Biodiversity and Evolution Institut de Biologia Evolutiva (CSIC-Univ. Pompeu Fabra) Barcelona Spain department of Integrative Ecology Estacion Biologica de Donana (EBD-CSIC) Seville Spain Museo entomologico de Leon Leon Nicaragua

The interactions between herbivores and their host plants play a key role in ecological processes. Understanding the width and nature of these interactions is funda- mental to ecology and conservation. Recent research on DNA-based inference of trophic associations suggests that the host range of phytophagous insects in the tropics may be wider than previously thought based on traditional observation. However, the reliability of molecular inference of ecological associations, still strongly dependent on PCR and thus exposed to the risk of contamination with environmental DNA, is under debate. Here, we explored alternative procedures to reduce the chance of amplification of external, nondiet DNA, including surface decontamination and analysis of mid/hind guts, comparing the results with those obtained using the standard protocol. We studied 261 specimens in eight species of Neotropical Chrysomelidae that yielded 316 psbA-trnH intergenic spacer sequences （cpDNA marker of putative diets） from unique and multiple-band PCR results. The taxonomic identity of these sequences was inferred using the automated pipeline BAGpipe, yielding results consistent with 31 plant families. Regardless of the proto- col used, a wide taxonomic spectrum of food was inferred for all chrysomelid species. Canonical Correspondence Analysis using these data revealed significant differences at- tributed mainly to species （expectedly, since they represent different ecologies）, but also to treatment （untreated vs. cleaned/gut samples） and PCR results （single vs. multiple bands）. Molecular identification of diets is not straightforward and, regardless of the species＇ niche breadth, combining approaches that reduce external contamination and studying multiple individuals per species may help increasing confidence in results.

关键词： food-webs gut content insect plant interaction molecular ecology molec-ular taxonomy psbA-trnH intergenic spacer

Distribution of trace metals and Pb isotopes in bottom sediments of the Murucupi River,North brazil

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International Journal of Sediment Research 2016年第3期31卷 226-236页

作者： Diomar Cavalcante Oliveira Jean michel Lafon Marcelo de Oliveira Lima Institute of Geosciences Federal University of Pára Environmental Section Evandro Chagas Institute

The Murucupi River belongs to the hydrographic network of the Para River estuary,at the southern portion of the Amazon River mouth,which consists of a fluvial-marine transitional zone under strong impact of both tidal and fluvial *** geochemical results obtained for bottom sediments from the Murucupi River,the Arrozal Channel,and the Para River indicate a natural variation of Pb,Cr,Cu,Zn,and Ni content among these water ways with no significant anthropogenic *** to the threshold effects level(TEL),the contents of trace metals do not offer risk to the local *** contrast,the differences in the Pb isotopic composition of sediments in the Murucupi River,the Arrozal Channel,and the Para River are *** isotopic signatures indicate an anthropogenic contribution of Pb in the Murucupi River originating from the domestic effluents of urban centers;industrial waste represented by red mud is not *** results demonstrate that the Pb isotopic signature is a prospective indicator for future contamination of bottom sediments by trace metals and is useful for identifying contaminants among the possible anthropogenic sources.

关键词： Bottom sediments Pb isotopes Trace metals Murucupi River Barcarena

Super-low friction of ta-C coating in presence of oleic acid

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Friction 2014年第2期2卷 156-163页

作者： Makoto KANO Jean michel MARTIN Kentaro YOSHIDA Maria Isabel de BARROS BOUCHET Division of Mechanical&Material Engineering Kanagawa Industrial Technology Center705-1 Shimo-ImaizumiEbinaKanagawaJapan LTDS Ecole Centrale de Lyon 69380EcullyFrance

Friction tests have been carried out on bearing steel friction pairs coated with a-C:H and ta-C under lubricated conditions with 1-hexadecene and pure oleic acid,*** results show that ta-C leads to the super-low regime with oleic acid(friction coefficient below 0.01)and that a-C:H is quite well lubricated by *** analyses by coupling X-ray photoelectron spectroscopy(XPS)and secondary ion mass spectrometry(SIMS)have been carried out in the case of oleic acid with ta-C and a-C:H *** show that tribochemical reactions have *** groups terminate the ta-C surface whereas a-C:H is covered by a thin tribofilm and is terminated by oleic acid *** superlow regime in the case of ta-C is mainly attributed to the presence of the OH-termination.

关键词： epoxy composite short carbon fiber friction wear

On the viability of wearing evaluation by Thin Layer Activation in the presence of non-occupationally exposed individuals

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Nuclear Science and Techniques 2022年第3期33卷 103-112页

作者： michel de Almeida Franca Julio Cezar Suita Paulo Fernando Ferreira Frutuoso e Melo Celso Marcelo Franklin Lapa Graduate Program of Nuclear Engineering COPPEFederal University of Rio de JaneiroRio de JaneiroRJ 21941914Brazil Instituto de Engenharia Nuclear(IEN-CNEN) Rio de Janeiro 21941614Brazil Comissao Nacional de Energia Nuclear(SEASE/DRS/CNEN) Rio de Janeiro 22290040Brazil

Thin Layer Activation is a nuclear technique that has key advantages over other wear measuring techniques for mechanical systems,especially for in site experiments on equipment important to safety in nuclear ***,it incurs radioactive dose and,thus,must be proved radiologically safe before use,otherwise,the utilization of this technique may be hindered *** said technique is safe previous to any operational/monetary cost is key,providing a methodology for this early assertion is the main contribution of this work—here,only non-occupationally exposed individuals are *** work offers a methodology,through a case study,to ascertain the Thin Layer Activation parameters to obtain safe levels of radioactive dose while maintaining statistically reliable *** methodology consists of using simulations,through the Monte Carlo Method,to obtain the floors and ceilings for the previously mentioned activation parameters based on operation and work conditions on site.

关键词： Thin Layer Activation Safety evaluation Simulation Equipment wearing

Increasing analyzable steel thickness for thin layer activation experiments

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Nuclear Science and Techniques 2020年第3期31卷 35-44页

作者： Joao Francisco de Oliveira Antunes Mauro Lucio Borges Lemos michel de Almeida Franca Julio Cezar Suita Celso Marcelo Franklin Lapa Instituto de Engenharia Nuclear Rio de Janeiro 21941-614Brazil Programa de Engenharia Nuclear-COPPE/UFRJ Riode Janeiro 21941-450Brazil

The thin layer activation technique(TLA)is very effective in wear analysis for tribological systems where disassembly is costly or *** its development in the 1970s,TLA has been applied through direct irradiation of solid targets using ionizing particle beams to obtain an activation with a specific *** profile is then used to measure wear in a variety of *** experiments rely heavily on how deep the normalized activation *** of 30μm to 50μm are obtained for constant activation by the standard method,which for many experiments is ***,many others would benefit greatly from a 300μm constant activation layer,such as high-performance engines,softer alloys(brakes),and oil transport *** this aim was the goal of this ***,we needed to find an adequate irradiation line for the TLA ***,another technique/system was developed(the Attenuation Wheel),which would bring the depth of constant activation from 50μm to 300μm.

关键词： Thin layer activation Wear Proton beam Attenuation wheel

Mechanism of superlubricity of a DLC/Si_(3)N_(4) contact in the presence of castor oil and other green lubricants

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Friction 2022年第10期10卷 1693-1706页

作者： Yun LONG Yang WANG Volker WEIHNACHT Stefan MAKOWSKI Momoji KUBO Jean michel MARTIN Maria-Isabel de BARROS BOUCHET Ecole Centrale de Lyon Laboratory of Tribology and System DynamicsUniversity of LyonEcully 69134France Institute for Materials Research Tohoku UniversitySendai 980-8577Japan department of Mechanical Systems Engineering Graduate School of EngineeringTohoku UniversitySendai 980-8579Japan Fraunhofer Institute for Material and Beam Technology(IWS) Dresden 01277Germany

To meet the surging needs in energy efficiency and eco-friendly lubricants,a novel superlubricious technology using a vegetable oil and ceramic materials is *** coupling different hydrogen-free amorphous carbon coatings with varying fraction of sp^(2) and sp^(3) hybridized carbon in presence of a commercially available silicon nitride bulk ceramic,castor oil provides superlubricity although the liquid vegetable oil film in the contact is only a few nanometres thick at *** a partial liquid film possibly separating surfaces in contact,local tribochemical reactions between asperities are essential to maintain superlubricity at low *** local pressure activates chemical degradation of castor oil generating graphitic/graphenic-like species on top of asperities,thus helping both the chemical polishing of surface and its chemical passivation by H and OH ***,the formation of the formation of–(CH_(2)–CH_(2))n–noligomers have been evidenced to have a major role in the friction *** simulation unveils that formation of chemical degradation products of castor oil on friction surfaces are favoured by the quantity of sp^(2)-hybridized carbon atoms in the amorphous carbon ***,tuning sp^(2)-carbon content in hydrogen-free amorphous carbon,in particular,on the top layers of the coating,provides an alternative way to control superlubricity achieved with castor oil and other selected green lubricants.

关键词： superlubricity diamond-like carbon(DLC) sp^(2)-hybridized carbon hydrogen passivation castor oil

Which algebraic groups are Picard varieties?

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Science China Mathematics 2015年第3期58卷 461-478页

作者： BRION michel Institut Fourier Universit'e de Grenoble

We show that every connected commutative algebraic group over an algebraically closed field of characteristic 0 is the Picard variety of some projective variety having only finitely many non-normal *** contrast,no Witt group of dimension at least 3 over a perfect field of prime characteristic is isogenous to a Picard variety obtained by this construction.

关键词： algebraic group Picard variety pinching

New results on the hadronic vacuum polarization contribution to the muon g-2

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Chinese Physics C 2010年第6期34卷 718-727页

作者： michel Davier Laboratoire de l'Acclrateur Linaire IN2P3/CNRSUniversit Paris-Sud 11

Results on the lowest-order hadronic vacuum polarization contribution to the muon magnetic anomaly are presented. They are based on the latest published experimental data used as input to the dispersion integral. Thus recent results on τ→υτππ^0 decays from Belle and on e^＋e^- annihilation to π^＋π^- from BABAR and KLOE are included. The new data, together with improved isospin-breaking corrections for τ decays, result into a much better consistency among the different results. A discrepancy between the Standard Model prediction and the direct g- 2 measurement is found at the level of 3σ.

关键词： muon magnetic moment vacuum polarization electron-positron annihilation tau decays g-2

Surgical Site Infections in Trauma and Orthopaedics at Bouaké Teaching Hospital (Côte d’Ivoire)

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Open Journal of Orthopedics 2024年第9期14卷 381-390页

作者： Loukou Blaise Yao Koffi Léopold Krah Aya Adelaïde Natacha Kouassi Kouamé Innocent M’bra Kouamé Jean-Eric Kouassi michel Kodo department of Trauma and Orthopaedics Bouak Teaching Hospital Bouak Cte dIvoire

Background: Surgical site infections are serious healthcare problems. The aim was to describe the epidemiological, diagnostic, therapeutic, and prognostic aspects of surgical site infections in Trauma and Orthopaedics at Bouaké Teaching Hospital. Method: This retrospective, descriptive, and analytical study was conducted from January 2019 to december 31, 2021. The data studied included prevalence, initial lesions, type of surgical intervention, type of SSI, bacteria involved, treatment, and outcomes. Results: Forty-four (11%) of the 399 patients included in the study developed a surgical site infection. The mean age was 27 years, with 36 male and 8 female. Initial lesions were predominantly open fractures (n = 31;70%), with a mean delay of 48 hours for surgical management. Emergency interventions accounted for 70% (n = 31) of cases. The NNISS infection risk score was 1 in 80% (n = 35) of cases. Superficial infections (n = 34;77%) appeared early, on a mean 6 days postoperatively. Bacteriological analysis primarily identified Pseudomonas aeruginosa (n = 10;23%), sensitive to Imipenem and Chloramphenicol but resistant to Amoxicillin-clavulanic acid, Ceftriaxone, Gentamicin, and Ciprofloxacin. Multidrug-resistant bacteria were found in 89% (n = 8) of cases, with all bacteria resistant to Ceftriaxone. Surgical revision was performed in 10 patients (23%), primarily involving debridement with hardware retention (n = 7;70%). Chloramphenicol was the most commonly used antibiotic post-antibiogram (61%). Outcomes were favourable in 98% of cases. Identified risk factors included the type of lesion according to NRC classification, the delay in managing open fractures, and the NNISS score. Conclusion: The prevalence of surgical site infection was 11%, favoured by the delayed operation of open fractures.

关键词： Surgical Site Infection Open Fractures Pseudomonas aeruginosa Ceftriaxone