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Microwave photonics

Science China(Information Sciences) 2022年第12期65卷 49-112页

作者： Jianping YAO jose CAPMAnY Microwave Photonics Research Laboratory School of Electrical Engineering and Computer Science University of Ottawa ITEAM Research Institute Universitat Politècnica de València iPronics Programmable Photonics

Microwave photonics, an interdisciplinary field that combines microwave engineering and photonic technology for the generation, transmission, processing, and control of microwave signals, to take advantage of the broad bandwidth, high frequency, and low loss offered by modern photonics, has been intensively researched for the last few decades, and numerous solutions have been proposed and demonstrated. In this article, an overview about microwave photonics is provided which covers the basic concepts of microwave photonics, photonic-assisted microwave signal generation, photonic-assisted microwave signal processing, and true time delay beamforming. The implementation of microwave photonic systems based on photonic integrated circuits is also reviewed, including the design, fabrication, and material platforms, application-specific photonic integrated circuits for microwave photonics, and programmable integrated microwave *** challenges and future applications of microwave photonics are also discussed.

关键词： microwave photonics photonic integrated circuits microwave photonic link microwave photonic signal processor optoelectronic oscillator radio over fiber

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Single-shot incoherent optical processing of microwave signals： opening the path to low cost high performance analog photonics

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Science Bulletin 2017年第9期62卷 652-653页

作者： jose Capmany ITEAM Research Institute Universitat Politecnica de Valencia Camino de Vera s/n 46022 Valencia Spain

Incoherent optical processing of microwave signals,where low-coherence broadband light sources are employed instead of costly mode locked lasers,has attracted great interest thanks to its wide applications in microwav... 详细信息

关键词： Single-shot incoherent optical processing of microwave signals:opening the path to low cost high performance analog photonics high MZM SnR mode SLD

Multitemporal landslide inventory analysis of an intertropical mountain in west-central Mexico——Basis for hazard management

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Journal of Mountain Science 2022年第6期19卷 1650-1669页

作者： Alejandro Cesar VALDES CARRERA Manuel E.MEnDOZA Teodoro CARLÓn ALLEnDE jose Luis MACIAS Centro de Investigaciones en Geografia Ambiental Universidad Nacional Autonoma de MexicoMorelia 58190Mexico Consejo nacional de Ciencia y Tecnologia-Instituto de Geofisica-Unidad Michoacan Universidad Nacional Autonoma de MexicoMorelia 58190Mexico Instituto de Geofisica-Unidad Michoacan Universidad Nacional Autonoma de MexicoMorelia 58190Mexico

Landslides in intertropical mountainous areas of Mexico are a natural hazard that could potentially generate a disaster. Despite this, many areas lack landslide inventories, making it difficult to monitor and efficiently manage the associated risks for local populations. For this reason, the aim of this research was to undertake a multitemporal landslide inventory and analyze its conditioning factors in the Pico de Tancítaro stratovolcano, which, in recent decades, has presented several high-risk geomorphological events with disastrous consequences for nearby localities. The spatial distribution of landslides and its conditioning factors were mapped at a 1:50,000 scale for the 1995-2020 period, through visual interpretation of orthophotos and satellite images(Landsat, SPOT, and SEnTInEL). The conditioning factors that link the most to landslides were Quaternary andesite and basaltic andesite rocks;volcanic cones, mountain river valleys, and very steep to steep slopes(30° to >45°), oriented to the South, north, and East;Andosols and Leptosols;and the oyamel fir and mixed forests. 505 landslide events classified into slides and flows that occurred in 1995, 2004, 2010, and 2015 were identified. new scars generated by the reactivation of landslide processes were also observed. The landslides in the study area were triggered by torrential rains caused by hurricanes and tropical storms;such as hurricanes Alex and Patricia. The inventory and analysis of conditioning factors highlighted the distribution and dynamics of slides and flows in the study area. In addition, the most important factors for studies of landslide susceptibility, hazards, and risks in the Pico de Tancítaro stratovolcano were identified, contributing to the management of geomorphological risks in intertropical mountain areas.

关键词： Geomorphology Mass wasting natural hazards Pico de Tancítaro stratovolcano Risk management

Thermal biology and locomotor performance in Phymaturus calcogaster:are Patagonian lizards vulnerable to climate change?

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Integrative Zoology 2021年第1期16卷 53-66页

作者： Rosa L.OBREGÓn jose A.SCOLARO nora R.IBARGÜEnGOYTÍA Marlin MEDInA Instituto de Diversidad y Evolución Austral (CENPAT-CONICET)Puerto MadrynArgentina Facultad de Ciencias naturales Universidad Nacional de la Patagonia San Juan BoscoTrelewArgentina Instituto de Investigaciones en Biodiversidad y Medioambiente Consejo Nacional de Investigaciones Científicas y Técnicas(INIBIOMA-CONICET)San Carlos de BarilocheArgentina Centro de Investigación Esquel de Montaña y Estepa Patagónica Consejo Nacional de Investigaciones Científicas y Técnicas(CIEMEP-CONICET)EsquelArgentina

Behavioral and physiological traits of ectotherms are especially sensitive to fluctuations of environmental *** particular,niche-specialist lizards are dependent on their physiological plasticity to adjust to changing environmental *** of the genus Phymaturus are viviparous,mainly herbivorous,and inhabit only rock promontories in the steppe environments of Patagonia and the ***,we examine the vulnerability of the southernmost Phymaturus species to global warming:the endemic Phymaturus calcogaster,which lives in a mesic environment in eastern *** studied body temperatures in the field(T_(b)),preferred body temperatures in a thermogradient(T_(pref)),the operative(T_(e))and environmental temperatures,and the dependence of running performance on body *** had a mean T_(b)(27.04℃)and a mean Te(31.15℃)both lower than their preferred temperature(T_(pref)=36.61℃)and the optimal temperature for running performance(T_(o)=37.13℃).Lizard activity seems to be restraint during the early afternoon due high environmental ***,both,the high safety margin and warming tolerance suggest that the expected increase in environmental temperatures due to global warming(IPCC report in 2018)would not threaten,but indeed enhance locomotor performance in this population.

关键词： climate change cold environment locomotor performance Patagonia Phymaturus

Application of micro-morphology in the physical characterization of urban road dust

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Particuology 2021年第1期19卷 146-155页

作者： Jithin jose B.Srimuruganandam School of Civil Engineering Vellore Institute of TechnologyVellore 632014Tamil NaduIndia

Urban road dust was collected from Vellore City,Tamil nadu,India,and *** electron microscopy(SEM)was used to examine road dust from nine sampling locations in the study *** image analysis was used to identify various shape factors of collected dust *** equivalent spherical diameter of most particles was between 10μm and 30μ*** particles had greater concentrations at locations with higher traffic *** were categorized into four classes based on their shape factors,viz.,spherical,mineral,elongated,or *** particles had the smallest mean equivalent diameter(1.95μm)and mineral particles had the largest diameter(33.3μm).Spherical particles made up the smallest portion of road dust(0-12%)in the study region and mineral particles made up the largest(45-65%).Elongated and irregular particles,each made up 23-30%of road *** dispersive X-ray spectroscopy analysis was used to identify the elemental composition of dust *** particles were mostly from combustion sources and mineral particles were largely of crustal *** individual source was found for irregular and elongated *** debris was the major source of irregular particles.

关键词： Road dust Scanning electron microscopy Shape factors Silt load Size distribution Particle shapes

Acoustic streaming and Sun's meridional circulation

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Research in Astronomy and Astrophysics 2016年第9期16卷 101-106页

作者： jose Manuel Valverde Faculty of Physics University of Seville

A vast number of physical processes involving oscillations of a bounded viscous fluid are relevantly influenced by acoustic streaming. When this happens a steady circulation of fluid develops in a thin boundary adjacent to the interface. Some examples are refracted sound waves, a fluid inside a spherical cavity undergoing torsional oscillations or a pulsating liquid droplet. Steady streaming around circular interfaces consists of a hemispherically symmetric recirculation of fluid from the equatorial plane to the polar axes closely resembling the meridional circulation pattern observed in the Sun＇s convection zone that determines the solar cycle. In this paper, it is argued that the acoustic pulsations exhibited by the Sun would lead to acoustic streaming in the boundary of the convection zone. A simple estimation using a typical dominant frequency of 3 mHz and the observed surface oscillation amplitude yields a steady streaming velocity Us - 10 m s^-1, which is on the order of the meridional circulation velocity observed in the Sun＇s convection zone.

关键词： Sun general -- Sun helioseismology -- Sun granulation -- Sun oscillations -- Sun fun-damental parameters -- Sun activity

Epidermal stem cells and skin tissue engineering in hair follicle regeneration

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World Journal of Stem Cells 2015年第4期7卷 711-727页

作者： María Eugenia Balaná Hernán Eduardo Charreau Gustavo jose Leirós Fundación Pablo Cassará-Instituto de Ciencia y Tecnología Dr.César Milstein Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Saladillo 2468 C1440FFXCiudad de Buenos AiresArgentina Technology Intelligence Unit ClarkeModet&C°Lavalle 1903°PisoC1047AAD Buenos AiresArgentina

The reconstitution of a fully organized and functional hair follicle from dissociated cells propagated under defined tissue culture conditions is a challenge stillpending in tissue engineering. The loss of hair follicles caused by injuries or pathologies such as alopecia not only affects the patients' psychological well-being, but also endangers certain inherent functions of the skin. It is then of great interest to find different strategies aiming to regenerate or neogenerate the hair follicle under conditions proper of an adult individual. Based upon current knowledge on the epithelial and dermal cells and their interactions during the embryonic hair generation and adult hair cycling, many researchers have tried to obtain mature hair follicles using different strategies and approaches depending on the causes of hair loss. This review summarizes current advances in the different experimental strategies to regenerate or neogenerate hair follicles, with emphasis on those involving neogenesis of hair follicles in adult individuals using isolated cells and tissue engineering. Most of these experiments were performed using rodent cells, particularly from embryonic or newborn origin. However, no successful strategy to generate human hair follicles from adult cells has yet been reported. This review identifies several issues that should be considered to achieve this objective. Perhaps the most important challenge is to provide threedimensional culture conditions mimicking the structure of living tissue. Improving culture conditions that allow the expansion of specific cells while protecting their inductive properties, as well as methods for selecting populations of epithelial stem cells, should give us the necessary tools to overcome the difficulties that constrain human hair follicle neogenesis. An analysis of patent trends shows that the number of patent applications aimed at hair follicle regeneration and neogenesis has been increasing during the last decade. This fiel

关键词： Adult stem cells Skin grafts Epidermis Multipotential differentiation Tissue regeneration Dermal papilla Epithelial-mesenchymal interactions

Isotopic niche provides an insight into the ecology of a symbiont during its geographic expansion

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Current Zoology 2022年第2期68卷 185-197页

作者： Enrique GOnZALEZ-ORTEGOn Marta PEREZ-MIGUEL jose I.nAVAS Pilar DRAKE jose A.CUESTA Instituto de Ciencias Marinas de Andalucia(ICMAn-CSIC) Campus Universitario Rio San PedroAvda.Republica Saharaui211519CadizPuerto RealSpain Unidad Asociada Crecimiento Azul CSIC-IFAPA El Puerto de Santa Maria SpainSpain Instituto de Investigacion y Formacion Agraria y Pesquera IFAPA-Centro Agua del PinoCtra.EI Rompido-Punta Umbriakm 3.821459 EI RompidoHuelvaSpain

The study of the recent colonization of a symbiont and its interaction with host communities in new locations is an opportunity to understand how they *** use of isotopic ratios in trophic ecology can provide measurements of a species'isotopic niche,as well as knowledge about how the isotopic niches between symbiont and host species *** isotope measurements were used to assess the sources of carbon assimilated by the host species(the bivalves Mytilus galloprovincialis and Scrobicularia plana)and their associated symbiont pea crab Afropinnotheres monodi,which occurs within these bivalves'mantle *** mixing model estimates suggest that all of them assimilate carbon from similar sources,particularly from pseudofaeces and particulate organic matter in this symbiotic system based on filter *** symbiotic species occupy comparable trophic levels and its association seems to be commensal or parasitic depending on the duration of such *** pea crab *** reflects a sex-specific diet,where males are more generalist than the soft females because the latter's habitat is restricted to the host *** high isotopic overlap between soft females and *** may reflect a good commensal relationship with the host.

关键词： bivalves commensal kleptoparasitism parasitism stable isotope trophic position

Magnetic field assisted fluidization:A modified Richardson-Zaki equation

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China Particuology 2007年第1期5卷 61-70页

作者： jose Manuel Valverde Antonio Castellanos Faculty of Physics Universidad de Sevilla Avenida Reina Mercedes s/n 41012 Sevilla Spain

Magnetic particles can be uniformly fluidized by coupling the gas flow with an externally imposed magnetic field. Interparticle forces generated by the magnetic field cause aggregation of the particles in chain-like structures preferentially oriented along the magnetic field lines. In the present paper, we study the implications of the formation of these special types of aggregates on the empirical Richardson-Zaki （RZ） equation, originally proposed to describe the expansion of fluidized beds of non-aggregated particles. We have addressed two important issues, namely the flow regime, which is a function of the size of the aggregates, and the effect of shape and orientation of the chain-like aggregates with respect to gas flow on fluid drag. We propose a modified RZ equation （MRZE） in which the velocity scale, given by the terminal settling velocity of the individual aggregates, and the RZ exponent are predetermined as a function of the chain length. The chain length depends on the ratio of the magnetic energy to gravitational energy, and is estimated from the magnetic field intensity, and particle magnetization, size and density. Predictions of the MRZE are successfully compared with published results in the literature on the expansion of magnetic particles in the presence of externally applied magnetic fields.

关键词： Fluidization Geldart B Magnetic particles Aggregation Richardson-Zaki equation