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Growth of RB Population in the Conversion Phase of Chlamydia Life Cycle

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Communications on Applied Mathematics and Computation 2024年第1期6卷 90-112页

作者： frederic y.M.Wan Department of Mathematics University of CaliforniaIrvineCA92697-3875USA

Upon infecting a host cell,the reticulate body(RB)form of the Chlamydia bacteria simply proliferates by binary fission for an extended *** data show only RB units in the infected cells 20 hours post infection(hpi),spanning nearly half way through the development *** data collected every 4 hpi,conversion to the elementary body(EB)form begins abruptly at a rapid rate sometime around 24 *** modeling proliferation and conversion as simple birth and death processes,it has been shown that the optimal strategy for maximizing the total(mean)EB population at host cell lysis time is a bang-bang control qualitatively replicating the observed conversion ***,the simple birth and death model for the RB proliferation and conversion to EB deviates in a significant way from the available data on the evolution of the RB population after the onset of RB-to-EB *** working with a more refined model that takes into account a small size threshold eligibility requirement for conversion noted in the available data,we succeed in removing the deficiency of the previous models on the evolution of the RB population without affecting the optimal bang-bang conversion strategy.

关键词： Chlamydia Life cycle Optimal control Maximal infectious spread Specie competitive survival

Fully integrated and broadband Si-rich silicon nitride wavelength converter based on Bragg scattering intermodal four-wave mixing

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Photonics Research 2024年第3期12卷 I0001-I0010页

作者： VALERIO VITALI THALÍA DOMÍNGUEZ BUCIO HAO LIU JOSÉMANUEL LUQUE GONZÁLEZ FRANCISCO JURADO-ROMERO ALEJANDRO ORTEGA-MOÑUX GLENN CHURCHILL JAMES C.GATES JAMES HILLIER NIKOLAOS KALFAGIANNIS DANIELE MELATI JENS H.SCHMID ILARIA CRISTIANI PAVEL CHEBEN J.GONZALO WANGÜEMERT-PÉREZ ÑIGO MOLINA-FERNÁNDEZ frederic gardes COSIMO LACAVA PERIKLIS PETROPOULOS Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK 2ElectricalComputer and Biomedical Engineering DepartmentUniversity of PaviaPavia 27100Italy 3Telecommunication Research Institute(TELMA)Universidad de MálagaCEI Andalucı´a TECHE.T.S.I.Telecomunicación29010 MálagaSpain 4School of Science and TechnologyNottingham Trent UniversityNottingham NG118NSUK 5Department of Electrical EngineeringEindhoven University of TechnologyEindhoven 5600 MBThe Netherlands 6Department of Materials Science and EngineeringUniversity of IoanninaIoannina 45110Greece 7Centre de Nanosciences et de NanotechnologiesUniversitéParis-SaclayCNRS91120 PalaiseauFrance 8Advanced Electronics and Photonics Research CenterNational Research Council CanadaOttawaOntario K1A 0R6Canada

Intermodal four-wave mixing(FWM)processes have recently attracted significant interest for all-optical signal processing applications thanks to the possibility to control the propagation properties of waves exciting distinct spatial modes of the same *** allows,in principle,to place signals in different spectral regions and satisfy the phase matching condition over considerably larger bandwidths compared to intramodal ***,the demonstrations reported so far have shown a limited bandwidth and suffered from the lack of on-chip components designed for broadband manipulation of different *** demonstrate here a silicon-rich silicon nitride wavelength converter based on Bragg scattering intermodal FWM,which integrates mode conversion,multiplexing and de-multiplexing functionalities *** system enables wavelength conversion between pump waves and a signal located in different telecommunication bands(separated by 60 nm)with a 3 dB bandwidth exceeding 70 nm,which represents,to our knowledge,the widest bandwidth ever achieved in an intermodal FWM-based system.

关键词： scattering pump modal

High-efficiency reflector-less dual-level silicon photonic grating coupler

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光子学研究:英文版 2023年第7期11卷 1275-1283页

作者： VALERIO VITALI THALíA DOMíNGUEZ BUCIO COSIMO LACAVA RICCARDO MARCHETTI LORENZO MASTRONAR TEERAPAT RUTIRAWUT GLENN CHURCHILL JOAQUíN FANECA JAMES C.GATES frederic gardes PERIKLIS PETROPOULOS Optoelectronics Research Centre University of SouthamptonSouthamptonSO171BJUK Electrical Computer and Biomedical Engineering DepartmentUniversity of Pavia27100 PaviaItaly Advanced Fiber Resources Milan S.r.l. 20098 San Donato MilaneseItaly Currently at Instituto de Microelectrónica de Barcelona IMB-CNM(CSIC)Campus UAB08193 BellaterraSpain

We present the design and experimentally demonstrate a dual-level grating coupler with subdecibel efficiency for a 220 nm thick silicon photonics waveguide which was fabricated starting from a 340 nm silicon-on-insulator *** proposed device consists of two grating levels designed with two different linear apodizations,with opposite chirping signs,and whose period is varied for each scattering unit.A coupling efficiency of-0.8 d B at1550 nm is experimentally demonstrated,which represents the highest efficiency ever reported in the telecommunications C-band in a single-layer silicon grating structure without the use of any backreflector or indexmatching material between the fiber and the grating.

关键词： waveguide scattering grating

All-silicon carrier accumulation modulator based on a lateral metal-oxide-semiconductor capacitor

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Photonics Research 2018年第5期6卷 373-379页

作者： KAPIL DEBNATH DAVID J.THOMSON WEIWEI ZHANG ALI Z.KHOKHAR CALLUM LITTLEJOHNS JAMES ByERS LORENZO MASTRONARDI MUHAMMAD K.HUSAIN KOUTA IBUKURO FREOERIC y.gardes GRAHAM T,REED SHINICHI SAITO Optoelectronics Research Centre University of SouthamptonSouthampton S017 1B JUK Faculty of Physical Sciences and Engineering University of SouthamptonSouthampton SO17 1BJUK

In silicon photonics, the carrier depletion scheme has been the most commonly used mechanism for demonstrating high-speed electro-optic modulation. However, in terms of phase modulation efficiency, carrieraccumulation-based devices potentially offer almost an order of magnitude improvement over those based on carrier depletion. Previously reported accumulation modulator designs only considered vertical metal-oxidesemiconductor(MOS) capacitors, which imposes serious restrictions on the design flexibility and integratability with other photonic components. In this work, for the first time to our knowledge, we report experimental demonstration of an all-silicon accumulation phase modulator based on a lateral MOS capacitor. Using a Mach–Zehnder interferometer modulator with a 500-μm-long phase shifter, we demonstrate high-speed modulation up to 25 Gbit∕s with a modulation efficiency(V_πL_π) of 1.53 V·cm.

关键词： All-silicon carrier accumulation modulator based on a lateral metal-oxide-semiconductor capacitor MZI

Urban heat mitigation by green and blue infrastructure:Drivers,effectiveness,and future needs

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The Innovation 2024年第2期5卷 145-166页

作者： Prashant Kumar Sisay E.Debele Soheila Khalili Christos H.Halios Jeetendra Sahani Nasrin Aghamohammadi Maria de Fatima Andrade Maria Athanassiadou Kamaldeep Bhui Nerea Calvillo Shi-Jie Cao frederic Coulon Jill L.Edmondson David Fletcher Edmilson Dias de Freitas Hai Guo Matthew C.Hort Madhusudan Katti Thomas Rodding Kjeldsen Steffen Lehmann Giuliano Maselli Locosselli Shelagh K.Malham Lidia Morawska Rajan Parajuli Christopher D.F.Rogers Runming yao Fang Wang Jannis Wenk Laurence Jones Global Centre for Clean Air Research(GCARE) School of SustainabilityCivil and Environmental EngineeringFaculty of Engineering and Physical SciencesUniversity of SurreyGuildford GU27XHUK Institute for Sustainability University of SurreyGuildford GU27XHSurreyUK School of Built Environment University of ReadingWhiteknightsReading RG66BUUK School Design and the Built Environment Curtin University Sustainability Policy InstituteKent StBentley 6102Western Australia Harry Butler Institute Murdoch UniversityMurdoch 6150Western Australia Atmospheric Sciences Department Institute of AstronomyGeophysics and Atmospheric SciencesUniversity of Sao PauloSao Paulo 05508-090Brazil Met Office FitzRoy RoadExeter EX13PBUK Department of Psychiatry and Nuffield Department of Primary Care Health Sciences Wadham CollegeUniversity of OxfordOxfordUK Centre for Interdisciplinary Methodologies University of WarwickWarwickUK School of Architecture Southeast University2 SipailouNanjing 210096China Cranfield University School of WaterEnvironment and EnergyCranfield MK430ALUK Plants PhotosynthesisSoil ClusterSchool of BiosciencesUniversity of SheffieldSheffield S102TNUK UK Centre for Ecology&Hydrology Environment Centre WalesDeiniol RoadBangor LL572UWUK Air Quality Studies Department of Civil and Environmental EngineeringThe Hong Kong Polytechnic UniversityHong KongChina Department of Forestry and Environmental Resources Faculty Excellence Program for Leadership in Public ScienceNorth Carolina State UniversityChancellorRaleighNC 27695USA Departments of Architecture&Civil Engineering and Chemical EngineeringUniversity of BathBath BA27AYUK School of Architecture University of NevadaLas VegasNV 89154USA Department of Tropical Ecosystems Functioning Center of Nuclear Energy in AgricultureUniversity of São PauloPiracicaba 13416-000Sao PauloBrazil School of Ocean Sciences Bangor UniversityMenai BridgeAnglesey LL595 ABUK International Laboratory for Air Quality and Health Science and Engine

The combination of urbanization and global warming leads to urban overheating and compounds the frequency and intensity of extreme heat events due to climate ***,the risk of urban overheating can be mitigated by urban green-blue-grey infrastructure(GBGI),such as parks,wetlands,and engineered greening,which have the potential to effectively reduce summer air *** many reviews,the evidence bases on quantified GBGI cooling benefits remains partial and the practical recommendations for implementation are *** systematic literature review synthesizes the evidence base for heat mitigation and related co-benefits,identifies knowledge gaps,and proposes recommendations for their implementation to maximize their *** screening 27,486 papers,202 were reviewed,based on 51 GBGI types categorized under 10 main *** GBGI(green walls,parks,street trees)have been well researched for their urban cooling ***,several other GBGI have received negligible(zoological garden,golf course,estuary)or minimal(private garden,allotment)*** most efficient air cooling was observed in botanical gardens(5.0±3.5℃),wetlands(4.9±3.2℃),green walls(4.1±4.2℃),street trees(3.8±3.1℃),and vegetated balconies(3.8±2.7℃).Under changing climate conditions(2070–2100)with consideration of RCP8.5,there is a shift in climate subtypes,either within the same climate zone(e.g.,Dfa to Dfb and Cfb to Cfa)or across other climate zones(e.g.,Dfb[continental warm-summer humid]to BSk[dry,cold semi-arid]and Cwa[temperate]to Am[tropical]).These shifts may result in lower efficiency for the current GBGI in the *** the importance of multiple services,it is crucial to balance their functionality,cooling performance,and other related co-benefits when planning for the future *** global GBGI heat mitigation inventory can assist policymakers and urban planners in prioritizing effective interventions to reduce the risk of urban overheating,fi

关键词： estuary walls extreme

Intermodal frequency generation in silicon-rich silicon nitride waveguides

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Photonics Research 2019年第6期7卷 615-621页

作者： C.LACAVA T.DOMINGUEZ BUCIO A.Z.KHOKHAR P.HORAK y.JUNG F.y.gardes D.J.RICHARDSON P.PETROPOULOS F.PARMIGIANI Optoelectronics Research Centre University of SouthamptonS0171BJ Southampton UK Currently at Microsoft Research UK CB1 2FB Cambridge UK

Dispersion engineering in optical waveguides allows applications relying on the precise control of phase matching conditions to be implemented. Although extremely effective over relatively narrow band spectral regions,dispersion control becomes increasingly challenging as the bandwidth of the process of interest *** matching can also be achieved by exploiting the propagation characteristics of waves exciting different spatial modes of the same waveguide. Phase matching control in this case relies on achieving very similar propagation characteristics across two, and even more, waveguide modes over the wavelengths of interest, which may be rather far from one another. We demonstrate here that broadband(>40 nm) four-wave mixing can be achieved between pump waves and a signal located in different bands of the communications spectrum(separated by50 nm) by exploiting interband nonlinearities. Our demonstration is carried out in the silicon-rich silicon nitride material platform, which allows flexible device engineering, allowing for strong effective nonlinearity at telecommunications wavelengths without deleterious nonlinear-loss effects.

关键词： Intermodal frequency silicon-rich silicon nitride waveguides

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

Reactive uptake of NO2 on volcanic particles: A possible source of HONO in the atmosphere

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Journal of Environmental Sciences 2020年第9期32卷 155-164页

作者： Manolis N.Romanias yangang Ren Benoit Grosselin Véronique Daële Abdelwahid Mellouki Pavla Dagsson-Waldhauserova frederic Thevenet IMT Lille Douai Univ.LilleSAGEF-59000 LilleFrance CNRS-ICARE/OSUC 45071 OrléansFrance Agricultural University of Iceland KeldnaholtReykjavik 112Iceland Faculty of Environmental Sciences Czech University of Life SciencesPrague 16521Czech Republic

The heterogeneous degradation of nitrogen dioxide(NO2) on five samples of natural Icelandic volcanic particles has been *** experiments were carried out under simulated atmospheric conditions using a coated wall flow tube(CWFT).The CWFT reactor was coupled to a blue light nitrogen oxides analyzer(NOx analyzer),and a long path absorption photometer(LOPAP) to monitor in real time the concentrations of NO2,NO and HONO,*** dark and ambient relative humidity conditions,the steady state uptake coefficients of NO2 varied significantly between the volcanic samples probably due to differences in magma composition and morphological variation related with the density of surface OH *** irradiation of the surface with simulated sunlight enhanced the uptake coefficients by a factor of three indicating that photo-induced processes on the surface of the dust ***,the product yields of NO and HONO were determined under both dark and simulated sunlight *** relative humidity was found to influence the distribution of gaseous products,promoting the formation of gaseous HONO.A detailed reaction mechanism is proposed that supports our experimental *** the atmospheric implications,our results suggest that the NO2 degradation on volcanic particles and the corresponding formation of HONO is expected to be significant during volcanic dust storms or after a volcanic eruption.

关键词： humidity gaseous source

Impact of switching from ranibizumab to aflibercept on the number of intravitreous injection and follow up visit in wet AMD:results of real life ELU study

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International Journal of Ophthalmology(English edition) 2020年第2期13卷 252-256页

作者： frederic Queguiner Kristina Bezirganyan Jean Christophe Courjaret Laurence Curel Guillaume Penaranda Maud Righini Chossegros Ophthalmology and Clinical Research Departments Hopital Saint JosephMarseille F-13008France Biostatistics Department Alphabio LaboratoryMarseille F-13003France

●AIM:To study if one of the two molecules could lead to a lower number of follow up visits and intra-vitreous injection(IVI)with the same efficacy.●METHODS:ELU(or"elected"in French)study is a retrospective study conducted in real life in patients presenting suboptimal response after ranibizumab IVI(phase 1)and secondary switched to aflibercept(phase 2).The number of follow up visits and IVI were compared in both *** acuity(VA)evolution and"switching"reasons were secondary analyzed.●RESULTS:We retrospectively included data of 33 patients(38 eyes)with age-related macular degeneration(AMD;mean age:77±7.7 y).The number of monthly follow up visits[median(Q1;Q3)]:was significantly lower with aflibercept(phase 2),respectively 1.0(0.81;1.49)visits in phase 1,versus 0.79(0.67;0.86)visits in phase *** median number of monthly IVI also significantly decreased in phase 2,respectively 0.67(0.55;0.90)IVI in phase 1,versus 0.55(0.45;0.67)IVI in phase *** mean VA evolution(VA final-VA initial)was similar in both phases,(P>0.05).Whatever the reason for"switching"(loss of efficacy,tachyphylaxis,tolerance problems),there was no incidence on VA evolution over the time.●CONCLUSION:Our results show that switching from ranibizumab to aflibercept in"suboptimal"patients significantly reduce the number of follow up visits and IVI,with a comparable *** decrease in visit number could improve patients’quality of life and reduce surgical risk by reducing the number of injections.

关键词： wet age-related macular degeneration anti-VEGF aflibercept ranibizumab follow up visit intravitreal injection visual acuity