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American journal of Analytical Chemistry 2012年第1期3卷 67-75页

作者： Christophe Y.Fischer Pascal Laurent Stephanie Heuskin Delphine Durieux Eric Haubruge francois j.verheggen Georges C.Lognay Department of Analytical Chemistry Gembloux Agro-Bio TechLiege UniversityLiegeBelgium Department of General and Organic Chemistry Gembloux Agro-Bio TechLiege UniversityLiegeBelgium Department of Biological and Industrial Chemistry Gembloux Agro-Bio TechLiege UniversityLiegeBelgium Department of Functional and Evolutionary Entomology Gembloux Agro-Bio TechLiege UniversityLiegeBelgium

These last few years the multicolored Asian ladybird, Harmonia axyridis (Pallas), previously introduced in Europe and North America as a biological control agent, has swiftly spread out on those territories and turns out to be a pest in several ways. In order to improve understanding of several key points of the biology of this ladybird, a novel fast-GC method of quantification of harmonine, the main defense alkaloid of H. axyridis, has been designed and validated using the accuracy profile concept for concentrations ranging from 13 to 264 μg/individual. This method allows quantifying harmonine in a single insect with a maximal error risk of 20%. For ladybirds collected in spring, mean harmonine concentration observed was 106.6 μg/individual with a very high standard deviation of 80.2 μg/individual, which can easily be explained by the strong asymmetry of the results distribution. Males and females seem equally chemically protected as the harmonine concentration did not significantly differ between sexes. This method is currently used to improve our comprehension of several key points of H. axyridis biology including aggregation behavior and aposematism.

关键词： Alkaloid Harmonine Harmonia axyridis Fast-GC Validation

From Control Theory to Gravitational Waves

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Advances in Pure Mathematics 2024年第2期14卷 49-100页

作者： jean-francois Pommaret CERMICS Ecole des Ponts Paris Tech Paris France

When D:ξ→η is a linear ordinary differential (OD) or partial differential (PD) operator, a “direct problem” is to find the generating compatibility conditions (CC) in the form of an operator D1:η→ξ such that Dξ = η implies D1η = 0. When D is involutive, the procedure provides successive first-order involutive operators D1,...,Dn when the ground manifold has dimension n. Conversely, when D1 is given, a much more difficult “inverse problem” is to look for an operator D:ξ→η having the generating CC D1η = 0. If this is possible, that is when the differential module defined by D1 is “torsion-free”, that is when there does not exist any observable quantity which is a sum of derivatives of η that could be a solution of an autonomous OD or PD equation for itself, one shall say that the operator D1 is parametrized by D. The parametrization is said to be “minimum” if the differential module defined by D does not contain a free differential submodule. The systematic use of the adjoint of a differential operator provides a constructive test with five steps using double differential duality. We prove and illustrate through many explicit examples the fact that a control system is controllable if and only if it can be parametrized. Accordingly, the controllability of any OD or PD control system is a “built in” property not depending on the choice of the input and output variables among the system variables. In the OD case and when D1 is formally surjective, controllability just amounts to the formal injectivity of ad(D1), even in the variable coefficients case, a result still not acknowledged by the control community. Among other applications, the parametrization of the Cauchy stress operator in arbitrary dimension n has attracted many famous scientists (G. B. Airy in 1863 for n = 2, j. C. Maxwell in 1870, E. Beltrami in 1892 for n = 3, and A. Einstein in 1915 for n = 4).

关键词： Differential Operator Differential Sequence Killing Operator Riemann Operator Bianchi Operator Cauchy Operator Control Theory Controllability Elasticity General Relativity

Do aphids actively search for ant partners？

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Insect Science 2015年第2期22卷 283-288页

作者： Christophe Y. Fischer Maryse Vanderplanck Georges C. Lognay Claire Detrain francois j. verheggen Laboratory of Analytical Chemistry University of Liege Gembloux Agro-Bio Tech Gembloux Research Institute of Biosciences Laboratory of Zoology University of Mons Mons Unit of Social Ecology Universit6 Libre de Bruxelles Brussels Department of Functional and Evolutionary Entomology University of Liege Gembloux Agro-Bio Tech Gembloux Belgium

The aphid-ant mutnalistic relationships are not necessarily obligate for neither partners but evidence is that such interactions provide them strong advantages in terms of global fitness. While it is largely assumed that ants actively search for their mutualistic partners namely using volatile cues; whether winged aphids （i.e., aphids＇ most mobile form） are able to select ant-frequented areas had not been investigated so far. Ant-frequented sites would indeed offer several advantages for these aphids including a lower predation pressure through ant presence and enhanced chances of establishing mutuaslistic interactions with neighbor ant colonies. In the field, aphid colonies are often observed in higher densities around ant nests, which is probably linked to a better survival ensured by ants＇ services. Nevertheless, this could also result from a preferential establishment of winged aphids in ant-frequented areas. We tested this last hypothesis through different ethological assays and show that the facultative myrmecophilous black bean aphid, Aphisfabae L., does not orientate its search for a host plant preferentially toward ant-frequented plants. However, our results suggest that ants reduce the number of winged aphids leaving the newly colonized plant. Thus, ants involved in facultative myrmecophilous interactions with aphids appear to contribute to structure aphid populations in the field by ensuring a better establishment and survival of newly established colonies rather than by inducing a deliberate plant selection by aphid partners based on the proximity of ant colonies.

关键词： ant aphid Aphisfabae Lasius niger mutualism partner research

Bacteria may contribute to distant species recognition in ant-aphid mutualistic relationships

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Insect Science 2017年第2期24卷 278-284页

作者： Christophe Y. Fischer Claire Detrain Philippe Thonart Eric Haubruge Frederic Francis francois j. verheggen Georges C. Lognay Laboratory of Analytical Chemistry University of Liege Gembloux Agro-Bio Tech Passage des Deportes 2 5030 Gembloux Unit of Social Ecology Universite Libre de Bruxelles CP231 50 avenue F. Roosevelt B-1050 Brussels Walloon Center of Industrial Biology University of Liege B40 Sart-Tilman 4000 Liege 4Functional and Evolutionary Entomology University of Liege Gembloux Agro-Bio Tech Passage des Deportes 2 5030 Gembloux Belgium

Mutualistic interactions between ant and aphid species have been the subject of considerable historical and contemporary investigations, the primary benefits being clean- ing and protection for the aphids and carbohydrate-rich honeydew for the ants. Questions remained, however, as to the volatile semiochemical factor influencing this relationship. A recent study highlighted the role of bacterial honeydew volatile compounds in ant at- traction. Here, ant＇s ability to distantly discriminate 2 aphid species was investigated based on bacterial honeydew semiochemicals emissions using a two-way olfactometer. Both the mutualistic aphid Aphis fabae L. and the nonmyrmecophilous aphid Acyrthosiphon pisum Harris were found to be attractive for the ant Lasius niger L. The level of attraction was similar in both assays （control vs. one of the aphid species）. However, when given a choice between these 2 aphid species, ants showed a significant preference for Aphis fabae. Honeydew volatiles, mostly from bacterial origins, are known to be a key element in ant attraction. Using the same olfactometry protocol, the relative attractiveness of volatiles emitted by honeydews collected from each aphid species and by bacteria isolated from each honeydew was investigated. Again, ants significantly preferred volatiles released by Aphis fabae honeydew and bacteria. This information suggests that microbial honeydew volatiles enable ants to distantly discriminate aphid species. These results strengthen the interest of studying the occurrence and potential impact of microorganisms in insect symbioses.

关键词： ant aphid bacteria honeydew mutualism recognition VOC

Testing semiochemicals from aphid, plant and conspecific： attraction of Harmonia axyridis

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Insect Science 2012年第3期19卷 372-382页

作者： Pascal D. Leroy Thomas Schillings julien Farmakidis Stephanie Heuskin Georges Lognay francois j. verheggen Yves Brostaux Eric Haubruge Frederic Francis Departments of Functional and Evolutionary Entomology Departments of Analytical Chemistry Departments of Applied Statistics Computer Science and Mathematics University of Liege Gembloux Agro-Bio Tech Gembloux Belgium

Harmonia axyridis Pallas （Coleoptera： Coccinellidae） is an invasive specie affecting the dynamics and composition of several guilds. Nowadays, no biological control method is available to reduce the populations of this harmful coccinellid. Attractants and semiochemicals seem to be the best alternative but only few studies have tested the impact of semiochemicals on this Asian lady beetle. In this work, through wind- tunnel experiments, semiochemicals from aphids （Z,E-nepetalactone, [E]-β-farnesene, a-pinene and β-pinene）, from coccinellids （[-]-β-earyophyllene） and from the nettle Urtica dioica L. were evaluated as potential attractants. The nettle volatile compounds （[Z]-3- hexenol and [E]-2-hexenal） were extracted using a Clevenger Apparatus and identified by headspace gas chromatography-mass spectroscopy. In the wind-tunnel experiments, the main components of the aphid alarm pheromone as well as a component of the aphid sexual pheromone strongly attracted both sexes of the Asian lady beetle while （-）-β- caryophyllene only attracted few individuals and had no impact on the males. The nettle extract as well as the （Z）-3-hexenol oriented both males and females to the odor source. The （E）-2-hexenal was shown to have no effect on females even if this green leaf volatile attracted males. Because Z,E-nepetalactone was identified as the most efficient attractant in the wind-tunnel experiments, this volatile was also tested in a potato field where H. axyridis has been showed to respond to this semiochemical. This study highlighted that Z,E-nepetalactone orientated the Asian lady beetle H. axyridis under natural condi- tions, indicating that this volatile compound could certainly help for an efficient biological control approach against this invasive specie.

关键词： aphids attractant Harmonia axyridis plant semiochemicals wind-tunnel

Epidemiology and risk factors for mortality in critically ill patients with pancreatic infection

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journal of Intensive Medicine 2024年第1期4卷 81-93页

作者： Marie Dejonckheere Massimo Antonelli Kostoula Arvaniti Koen Blot Ben CreaghBrown Dylan Wde Lange jan De Waele Mieke Deschepper Yalim Dikmen George Dimopoulos Christian Eckmann Guy francois Massimo Girardis Despoina Koulenti Sonia Labeau jeffrey Lipman Fernando Lipovestky Emilio Maseda Philippe Montravers Adam Mikstacki joseArtur Paiva Cecilia Pereyra jordi Rello jeanfrancois Timsit Dirk Vogelaers Stijn Blot the Abdominal Sepsis Study(AbSeS)group on behalf of the Trials Group of the European Society of Intensive Care Medicine Department of Internal Medicine and Pediatrics Faculty of Medicine and Health SciencesGhent UniversityGhentBelgium Department of Anesthesiology Intensive Care and Emergency MedicineFondazione Policlinico Universitario A.Gemelli IRCCSRomeItaly UniversitàCattolica del Sacro Cuore RomeItaly Intensive Care Unit Papageorgiou University Affiliated HospitalThessaloníkiGreece Department of Epidemiology and Public Health SciensanoIxellesBelgium Surrey Perioperative Anaesthetic Critical Care Collaborative Research Group(SPACeR) Royal Surrey County HospitalGuildfordUK Department of Clinical and Experimental Medicine University of SurreyGuildfordUK Department of Intensive Care Medicine University Medical Center UtrechtUniversity UtrechtUtrechtthe Netherlands Department of Intensive Care Medicine Ghent University HospitalGhentBelgium Data Science Institute Ghent University HospitalGhentBelgium Department of Anesthesiology and Reanimation Cerrahpasa School of MedicineIstanbul University-CerrahpasaIstanbulTurkey rd Department of Critical Care “EVGENIDIO”HospitalNational and Kapodistrian University of AthensAthensGreece Department of General Visceral and Thoracic SurgeryKlinikum Hannoversch-MuendenGoettingen UniversityGöttingenGermany Division of Scientific Affairs-Research European Society of Intensive Care MedicineBrusselsBelgium Anesthesia and Intensive Care Department University Hospital of ModenaModenaItaly UQ Centre for Clinical Research Faculty of MedicineThe University of QueenslandBrisbaneQLDAustralia nd Critical Care Department Attikon University HospitalAthensGreece Department of Nursing Faculty of EducationHealth and Social WorkUniversity College GhentGhentBelgium jamieson Trauma Institute The University of QueenslandBrisbaneQLDAustralia Nimes University Hospital University of MontpellierNimesFrance Critical Care Department Hospital of the Interamerican Open University(UAI)Buenos AiresArgentina Surgical Critical Care Department of AnesthesiaHospital Universitario

Background:The AbSeS-classification defines specific phenotypes of patients with intra-abdominal infection based on the(1)setting of infection onset(community-acquired,early onset,or late-onset hospital-acquired),(2)presence or absence of either localized or diffuse peritonitis,and(3)severity of disease expression(infection,sepsis,or septic shock).This classification system demonstrated reliable risk stratification in intensive care unit(ICU)patients with intra-abdominal *** study aimed to describe the epidemiology of ICU patients with pancreatic infection and assess the relationship between the components of the AbSeS-classification and ***:This was a secondary analysis of an international observational study(“AbSeS”)investigating ICU patients with intra-abdominal *** patients with pancreatic infection were included in this analysis(n=165).Mortality was defined as ICU mortality within 28 days of observation for patients discharged earlier from the *** with mortality were assessed using logistic regression analysis and reported as odds ratio(OR)and 95%confidence interval(CI).Results:The overall mortality was 35.2%(n=58).The independent risk factors for mortality included older age(OR=1.03,95%CI:1.0 to 1.1 P=0.023),localized peritonitis(OR=4.4,95%CI:1.4 to 13.9 P=0.011),and persistent signs of inflammation at day 7(OR=9.5,95%CI:3.8 to 23.9,P<0.001)or after the implementation of additional source control interventions within the first week(OR=4.0,95%CI:1.3 to 12.2,P=0.013).Gramnegative bacteria were most frequently isolated(n=58,49.2%)without clinically relevant differences in microbial etiology between survivors and ***:In pancreatic infection,a challenging source/damage control and ongoing pancreatic inflammation appear to be the strongest contributors to an unfavorable short-term *** this limited series,essentials of the AbSeS-classification,such as the setting of infection onset,diffuse

关键词： Pancreatic infection Intensive care unit Mortality Intra-abdominal infection Sepsis

Inverse Design of Strained Graphene Surfaces for Electron Control

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Communications in Computational Physics 2023年第6期33卷 235-260页

作者： francois Fillion-Gourdeau Emmanuel Lorin Steve Maclean Institute for Quantum Computing University of WaterlooWaterlooOntarioCanadaN2L 3G1 School of Mathematics and Statistics Carleton UniversityOttawaCanadaK1S 5B6 Centre de Recherches Mathematiques Universite de MontrealMontrealCanadaH3T 1J4

This paper is devoted to the inverse design of strained graphene surfaces for the control of electrons in the semi-classical optical-like *** that charge carriers are described by the Dirac equation in curved-space and exploiting the fact that wave propagation can be described by ray-optics in this regime,a general computational strategy is proposed in order to find strain fields associated with a desired effective refractive index *** latter is first determined by solving semi-classical trajectories and by optimizing a chosen objective functional using a genetic ***,the graded refractive index corresponding to the strain field is obtained by using its connection to the metric component in isothermal *** coordinates are evaluated via numerical quasiconformal transformations by solving the Beltrami equation with a finite volume *** graphene surface deformation is finally optimized,also using a genetic algorithm,to reproduce the desired index of *** analytical results and numerical experiments are performed to illustrate the methodology.

关键词： Graphene isothermal coordinates Beltrami equation gravitational lens waveguide finite volume method genetic algorithm Dirac equation

Impact of time to diagnosis on the occurrence of cardiogenic shock in MIS‑C post‑COVID-19 infection

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World journal of Pediatrics 2023年第6期19卷 595-604页

作者： Said Bichali Mathilde Bonnet Marie‑Emilie Lampin jean‑Benoit Baudelet Heloise Reumaux Olivia Domanski Thameur Rakza Alexandre Delarue Morgan Recher jerome Soquet francois Dubos Stephane Leteurtre Ali Houeijeh francois Godart Pediatric Cardiology Univ.LilleCHU Lille2 Avenue Oscar Lambret59000 LilleFrance Pediatric Intensive Care Univ.LilleCHU Lille59000 LilleFrance ULR 2694‑Metrics:Evaluation des Technologies de Sante et des Pratiques Medicales Univ.Lille59000 LilleFrance Pediatric Rhumatology Univ.LilleCHU Lille59000 LilleFrance Cardiac Surgery Univ.LilleCHU Lille59000 LilleFrance Pediatric Emergency Univ.LilleCHU Lille59000 LilleFrance

Background In multisystem inflammatory syndrome in children(MIS-C),diagnostic delay could be associated with *** study aims to measure the time to diagnosis in MIS-C,assess its impact on the occurrence of cardiogenic shock,and specify its *** A single-center prospective cohort observational study was conducted between May 2020 and july 2022 at a tertiary care *** meeting the World Health Organization MIS-C criteria were included.A long time to diagnosis was defined as six days or *** on time to diagnosis were collected by two independent *** primary outcome was the occurrence of cardiogenic *** regression and receiver operating characteristic curve analysis were used for outcomes,and a Cox proportional hazards model was used for *** Totally 60 children were assessed for inclusion,and 31 were finally analyzed[52%males,median age 8.8(5.7-10.7)years].The median time to diagnosis was 5.3(4.2-6.2)*** univariable analysis,age above the median,time to diagnosis,high C-reactive protein,and high N-terminal pro-B-type natriuretic peptide(NT-proBNP)were associated with cardiogenic shock[odds ratio(OR)6.13(1.02-36.9),2.79(1.15-6.74),2.08(1.05-4.12),and 1.70(1.04-2.78),respectively].In multivariable analysis,time to diagnosis≥6 days was associated with cardiogenic shock[adjusted OR(aOR)21.2(1.98-227)].Time to diagnosis≥6 days had a sensitivity of 89% and a specificity of 77% in predicting cardiogenic shock;the addition of age>8 years and NT-proBNP at diagnosis≥11,254 ng/L increased the specificity to 91%.Independent determinants of short time to diagnosis were age<8.8 years[aHR 0.34(0.13-0.88)],short distance to tertiary care hospital[aHR 0.27(0.08-0.92)],and the late period of the COVID-19 pandemic[aHR 2.48(1.05-5.85)].Conclusions Time to diagnosis≥6 days was independently associated with cardiogenic shock in *** diagnosis and treatment are crucial to avoid the use of inotropes and

关键词： COVID-19 Delay in diagnosis Heart failure MIS-C SARS-CoV-2

Cloning and functional characterization of two cDNAs encoding NADPH-dependent 3-ketoacyl-CoA reductased from developing cotton fibers

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Cell Research 2005年第6期15卷 465-473页

作者： francois MA PUjOL,Alexander j KASTANIOTIS,j Kalervo HILTUNEN Biocenter Oulu and Department of Biochemistry University of Oulu P.O. Box 3000 FIN-90014 University of Oulu Finland Biocenter Oulu and Department of Biochemistry University of Oulu P.O. Box 3000 FIN-90014 University of Oulu Finland Biocenter Oulu and Department of Biochemistry University of Oulu P.O. Box 3000 FIN-90014 University of Oulu Finland

Genes encoding enzymes involved in biosynthesis of very long chain fatty acids were significantly up-regulatedduring early cotton fiber development. Two cDNAs, GhKCR1 and GhKCR2 encoding putative cotton 3-ketoacyl-CoAreductases that catalyze the second step in fatty acid elongation, were isolated from developing cotton fibers. GhKCR1and 2 contain open reading frames of 963 bp and 924 bp encoding proteins of 320 and 307 amino acid residues,respectively. Quantatitive RT-PCR analysis showed that both these genes were highly preferentially expressed duringthe cotton fiber elongation period with much lower levels recovered from roots, stems and leaves. GhKCR1 and 2showed 30%-32% identity to Saccharomyces cerevisiae Ybr159p at the deduced amino acid level. These cotton cDNAswere cloned and expressed in yeast haploid ybr159w? mutant that was deficient in 3-ketoacyl-CoA reductase ***-type growth rate was restored in ybr159w? cells that expressed either GhKCR1 or 2. Further analysis showed thatGhKCR1 and 2 were co-sedimented within the membranous pellet fraction after high-speed centrifugation, similar to theyeast endoplasmic reticulum marker ScKar2p. Both GhKCR(s) showed NADPH-dependent 3-ketoacyl-CoA reductaseactivity in an in vitro assay system using palmitoyl-CoA and malonyl-CoA as substrates. Our results suggest thatGhKCR1 and 2 are functional orthologues of ScYbr159p.

关键词： very-long-chain fatty acids endoplasmic reticulum fatty acid elongation system 3-ketoacyl-CoA reductase Gossypium hirsutum short-chain alcohol dehydrogenase/reductase protein family.

Cross-sectional associations between cortical thiclmess and physical activity in older adults with spontaneous memory complaints:The MAPT Study

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journal of Sport and Health Science 2023年第3期12卷 324-332页

作者： jérémy Raffin Yves Rolland Clara Fischer jean-francois Mangin Audrey Gabelle Bruno Vellas Philipe de Souto Barreto the MAPT/DSA Group Gérontopôle de Toulouse Institut du VieillissementCentre Hospitalo-Universitaire de ToulouseToulouse 31000France UniversitéPaul-Sabatier/Institut National de la Santéet de la Recherche Médicale UnitéMixte de Recherche 1027 Facultéde médecineUniversity of Toulouse ⅢToulouse 31000France Centre pour l'Acquisition et le Traitement des Images Multicenter Neuroimaging Platform NeurospinUniversitéParis-SaclayGif sur Yvette 91191France Memory Resources and Research Center Montpellier University HospitalMontpellier 34295France Institut National de la Santéet de la Recherche Médicale Unité1061 i-site Montpellier Universitéd'Excellence University of MontpellierMontpellier 34090France 不详

Background:Age-related changes in brain structure may constitute the starting point for cerebral function *** activity(PA)demonstrated favorable associations with total brain volume,but its relationship with cortical thickness(CT)remains *** investigated the cross-sectional associations between PA level and CT in community-dwelling people aged 70 years and ***:A total of 403 older adults aged 74.8±4.0 years(mean±SD)who underwent a baseline magnetic resonance imaging examination and who had data on PA and confounders were *** was assessed with a *** were categorized according to PA *** linear regressions were used to compare the brain CT(mm)of the inactive group(no PA at all)with 6 active groups(growing PA levels)in 34 regions of ***:Compared with inactive persons,people who achieved PA at a level of 1500-1999 metabolic equivalent task-min/week(i.e.,about6-7 h of brisk walking for exercise) and those who achieved it at 2000-2999 metabolic equivalent task-min/week(i.e.,8-11 h of brisk walking for exercise)had higher CT in the fusiform gyrus and the temporal ***,dose-response associations between PA and CT were found in the fusiform gyrus(B=0.011,SE=0.004,adj.p=0.035),the temporal pole(B=0.026,SE=0.009,adj.p=0.048),and the caudal middle frontal gyrus,the entorhinal,medial orbitofrontal,lateral occipital,and insular ***:This study demonstrates a positive association between PA level and CT in temporal areas such as the fusiform gyrus,a brain region often associated to Alzheimer’s disease in people aged 70 years and *** investigations focusing on PA type may help to fulfil remaining knowledge gaps in this field.

关键词： Alzheimer's disease Brain aging Cortical thickness Physical activity