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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 Electrical Computer and Biomedical Engineering DepartmentUniversity of PaviaPavia 27100Italy Telecommunication Research Institute(TELMA) Universidad de MálagaCEI Andalucı´a TECHE.T.S.I.Telecomunicación29010 MálagaSpain School of Science and Technology Nottingham Trent UniversityNottingham NG118NSUK Department of Electrical Engineering Eindhoven University of TechnologyEindhoven 5600 MBThe Netherlands Department of Materials Science and Engineering University of IoanninaIoannina 45110Greece Centre de Nanosciences et de Nanotechnologies UniversitéParis-SaclayCNRS91120 PalaiseauFrance Advanced Electronics and Photonics Research Center National 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

Design of Poiseuille flow Controllers Using the Method of Inequalities

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International Journal of Automation and computing 2009年第1期6卷 14-21页

作者： John McKernan james f. Whidborne George Papadakis Department of Mechanical Engineering King s College London Strand Department of Aerospace Sciences Cranfield University

This paper investigates the use of the method of inequalities （MoI） to design output-feedback compensators for the problem of the control of instabilities in a laminar plane Poiseuille flow. In common with many flows, the dynamics of streamwise vortices in plane Poiseuille flow are very non-normal. Consequently, small perturbations grow rapidly with a large transient that may trigger nonlinearities and lead to turbulence even though such perturbations would, in a linear flow model, eventually decay. Such a system can be described as a conditionally linear system. The sensitivity is measured using the maximum transient energy growth, which is widely used in the fluid dynamics community. The paper considers two approaches. In the first approach, the MoI is used to design low-order proportional and proportional-integral （PI） controllers. In the second one, the MoI is combined with Mcfarlane and Glover＇s H∞ loop-shaping design procedure in a mixed-optimization approach.

关键词： Transient energy growth transient behaviour flow control Poiseuille flow method of inequalities (MoI) mixed opti-mization H∞-optimization.

Perceptual tolerance neighborhood-based similarity in content-based image retrieval and classification

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International Journal of Intelligent Computing and Cybernetics 2012年第2期5卷 164-185页

作者： Amir H.Meghdadi james f.Peters Electrical and Computer Engineering University of ManitobaWinnipegCanada School of Mathematics University of HyderabadHyderabadIndia

Purpose–The purpose of this paper is to demonstrate the effectiveness and advantages of using perceptual tolerance neighbourhoods in tolerance space-based image similarity measures and its application in content-based image classification and ***/methodology/approach–The proposed method in this paper is based on a set-theoretic approach,where an image is viewed as a set of local visual *** method also includes a tolerance relation that detects the similarity between pairs of elements,if the difference between corresponding feature vectors is less than a threshold 2(0,1).findings–It is shown that tolerance space-based methods can be successfully used in a complete content-based image retrieval(CBIR)***,it is shown that perceptual tolerance neighbourhoods can replace tolerance classes in CBIR,resulting in more accuracy and less ***/value–The main contribution of this paper is the introduction of perceptual tolerance neighbourhoods instead of tolerance classes in a new form of the Henry-Peters tolerance-based nearness measure(tNM)and a new neighbourhood-based tolerance-covering nearness measure(tcNM).Moreover,this paper presents a side–by–side comparison of the tolerance space based methods with other published methods on a test dataset of images.

关键词： Image similarity Nearness measure Distance measurement Content-based image retrieval(CBIR) Perceptual tolerance neighbourhoods Tolerance spaces Tolerances Measurement

Semi-transparent,flexible,and electrically conductive silicon mesh by capillarity-driven welding of vapor-liquid-solid-grown nanowires over large areas

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Nano Research 2020年第5期13卷 1465-1471页

作者： Thomas A.Celano Seokhyoung Kim David J.Hill james f.Cahoon Department of Chemistry University of North Carolina at Chapel HillChapel HillNC 27599-3290USA

Bottom-up synthesis of semiconductor nanowires(NWs)by the vapor-liquid-solid(VLS)mechanism has enabled diverse technological applications for these *** metallic NWs,however,it has been challenging to form large-area interconnected NW ***,we generate centimeter-scale meshes of mechanically and electrically interconnected Si NWs by sequentially growing,collapsing,and joining the NWs using a capillarity-driven welding *** fabricate meshes from VLS-grown NWs ranging in diameter from 20 to 100 nm and find that the meshes are three-dimensional with a thickness ranging from^1 to^10 microns depending on the NW *** extinction measurements reveal that the networks are semi-transparent with a color that depends on the absorption and scattering characteristics of individual ***,active voltage contrast imaging of both centimeter-and micron-scale meshes reveals widespread electrical *** a sacrificial layer,we demonstrate that the mesh can be liberated from the growth substrate,yielding a highly flexible and transparent *** transport measurements both on the growth substrate and on liberated,flexible films reveal electrical conduction across a centimeter scale with a sheet resistance of^160-180 kΩ/square that does not change significantly upon *** the ability to encode complex functionality in semiconductor NWs through the VLS process,we believe these meshes of networked NWs could find application as neuromorphic memory,electrode scaffolds,and bioelectronic interfaces.

关键词： semiconductor nanowire conductive network flexible electronics welding thermal annealing active-voltage contrast

The HIf-1α/PLOD2 axis integrates extracellular matrix organization and cell metabolism leading to aberrant musculoskeletal repair

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Bone Research 2024年第2期12卷 289-301页

作者： Heeseog Kang Amy L.Strong Yuxiao Sun Lei Guo Conan Juan Alec C.Bancroft Ji Hae Choi Chase A.Pagani Aysel A.fernandes Michael Woodard Juhoon Lee Sowmya Ramesh Aaron W.james David Hudson Kevin N.Dalby Lin Xu Robert J.Tower Benjamin Levi Center for Organogenesis Regeneration and TraumaDepartment of SurgeryUniversity of Texas SouthwesternDallasTX 75390USA Section of Plastic Surgery Department of SurgeryUniversity of MichiganAnn ArborMI 48109USA Quantitative Biomedical Research Center Peter O’Donnell Jr.School of Public HealthUniversity of Texas SouthwesternDallasTX 75390USA Department of Orthopedics and Sports Medicine University of WashingtonSeattleWA 98195USA Division of Chemical Biology and Medicinal Chemistry College of PharmacyUniversity of Texas at AustinAustinTX 78712USA Department of Pathology Johns Hopkins UniversityBaltimoreMD 21218USA

While hypoxic signaling has been shown to play a role in many cellular processes,its role in metabolism-linked extracellular matrix(ECM)organization and downstream processes of cell fate after musculoskeletal injury remains to be ***(HO)is a debilitating condition where abnormal bone formation occurs within extra-skeletal *** andhypoxia-inducible factor 1α(HIf-1α)activation have been shown to promote ***,the underlying molecular mechanisms bywhich the HIf-1αpathway in mesenchymal progenitor cells(MPCs)contributes to pathologic bone formation remain to ***,we used a proven mouse injury-induced HO model to investigate the role of HIf-1αon aberrant cell ***-cell RNA sequencing(scRNA-seq)and spatial transcriptomics analyses of the HO site,we found that collagen ECM organizationis the most highly up-regulated biological process in *** mesenchymal cell-specific deletion of Hif1α(Hoxa11-CreER^(T2);Hif1a^(fl/fl))significantly mitigated HO in ***-seq analysis of these Hoxa11-CreER^(T2);Hif1a^(fl/fl)mice identified the PLOD2/LOXpathway for collagen cross-linking as downstream of the HIf-1αregulation of ***,our scRNA-seq data and mechanisticstudies further uncovered that glucose metabolism in MPCs is most highly impacted by HIf-1α*** a translational aspect,a pan-LOX inhibitor significantly decreased HO.A newly screened compound revealed that the inhibition of PLOD2 activity in MPCssignificantly decreased osteogenic differentiation and glycolytic *** suggests that the HIf-1α/PLOD2/LOX axis linked tometabolism regulates HO-forming MPC *** results suggest that the HIf-1α/PLOD2/LOX pathway represents a promisingstrategy to mitigate HO formation.

关键词： metabolism skeletal aberrant

Round spermatid injection into human oocytes:a systematic review and meta-analysis

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Asian Journal of Andrology 2021年第4期23卷 363-369页

作者： Brent M Hanson Taylor P Kohn Alexander W Pastuszak Richard T Scott jr Philip J Cheng james M Hotaling Department of Reproductive Endocrinology and Infertility IVI-Reproductive Medicine Associates of New JerseyBasking RidgeNJ 07920USA Department of Urology The Brady Urological Institute at Johns Hopkins UniversityBaltimoreMD 21287USA Department of Surgery University of Utah Center for Reconstructive Urology and Men's HealthSalt Lake CityUT 84108USA

Many azoospermic men do not possess mature spermatozoa at the time of surgical sperm *** study is a systematic review and meta-analysis evaluating outcomes following round spermatid injection(ROSI),a technique which utilizes immature precursors of spermatozoa for *** electronic search was performed to identify relevant articles published through October *** cohort studies in English involving male patients who had round spermatids identified and used for fertilization with human oocytes were *** rate,pregnancy rate,and resultant delivery rate were assessed following ***-analysis outcomes were analyzed using a random-effects *** were extracted from 22 studies involving 1099 couples and 4218 embryo *** fertilization rate after ROSI was 38.7%(95%confidence interval[CI]:31.5%–46.3%),while the pregnancy rate was 3.7%(95%CI:3.2%–4.4%).The resultant delivery rate was low,with 4.3%of embryo transfers resulting in a delivery(95%CI:2.3%–7.7%).The pregnancy rate per couple was 13.4%(95%CI:6.8%–19.1%)and the resultant delivery rate per couple was 8.1%(95%CI:6.1%–14.4%).ROSI has resulted in clinical pregnancies and live births,but success rates are considerably lower than those achieved with mature *** this technique may be a feasible alternative for men with azoospermia who decline other options,couples should be aware that the odds of a successful delivery are greatly diminished and the prognosis is relatively poor.

关键词： azoospermia in vitro fertilization infertility spermatozoa testis

RECENT RESULTS fORM EARTHBASED OBSERVATIONS Of MARS

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紫金山天文台台刊 1998年第2期 33-43页

作者： james f.Bell III Cornell University Department of Astronomy Ithaca NY 14853-6801 USA

Even in an age of increasing spacecraft exploration, telescopic observations of Mars continue to provide new data and new insights into the nature of the Martian surface, atmosphere, and climate. Three major technological advances in the last decade, combinde, have allowed telescopic observations to increase our knowledge of the planet: (1) Advances in infrared, near-infrared, and radio wavelength array detector and telescope technology, allowing high spatial and/ or high spectral resolution imaging in new and diagnostic wavelength regions; (2) The advent of routine space-based telescopic observations of Mars using the Hubble Space Telescope , providing the ability to study the planet at high spatial resolution over a much longer part of its orbit than from groundbased telescopes, and offsetting some of the inherent loss in resolution associated with the recent series of aphelic oppositions of the planet; and (3) The widespread use and availability of CCD cameras and powerful telescopes in the 10 -

关键词：火星紫金山地面天文台结果卷柏

Murine lung eosinophil activation and chemokine production in allergic airway inflammation

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Cellular & Molecular Immunology 2010年第5期7卷 361-374页

作者： C Edward Rose jr Joanne A Lannigan Paul Kim james J Lee Shu Man fu Sun-sang J Sung Division of Pulmonary and Critical Care Department of MedicineUniversity of Virginia School of MedicineCharlottesvilleVAUSA Department of Microbiology University of Virginia School of MedicineCharlottesvilleVAUSA Center for Immunity Inflammationand Regenerative Medicine and Division of NephrologyDepartment of MedicineUniversity of Virginia School of MedicineCharlottesvilleVAUSA Division of Pulmonary Medicine Department of Biochemistry and Molecular BiologyMayo Clinic ArizonaScottsdaleAZUSA

Eosinophils play important roles in asthma and lung *** models are widely used for assessing the functional significance and mechanistic basis for eosinophil involvements in these ***,little is known about tissue eosinophils in *** addition,little data on eosinophil chemokine production during allergic airway inflammation are *** this study,the properties and functions of homeostatic and activated eosinophils were *** from normal tissues expressed costimulation and adhesion molecules B7-1,B7-2 and ICAM-1 for Ag presentation but little major histocompatibility complex(MHC)class II,and were found to be poor stimulators of T-cell ***,these eosinophils expressed high levels of chemokine mRNA including C10,macrophage inflammatory protein(MIP)-1a,MIP-1c,MIP-2,eotaxin and monocyte chemoattractant protein-5(MCP-5),and produced chemokine *** intracellular chemokines decreased rapidly with concomitant surface marker downregulation upon in vitro culturing consistent with piecemeal *** eosinophils from mice with induced allergic airway inflammation exhibited increased chemokines mRNA expression and chemokines protein production and upregulated MHC class II and CD11c *** were also found to be the predominant producers of the CCR1 ligands CCL6/C10 and CCL9/MIP-1c in inflamed *** production of C10 and MIP-1c correlated with the marked influx of CD11bhigh lung dendritic cells during allergic airway inflammation and the high expression of CCR1 on these dendritic cells(DCs).The study provided baseline information on tissue eosinophils,documented the upregulation of activation markers and chemokine production in activated eosinophils,and indicated that eosinophils were a key chemokine-producing cell type in allergic lung inflammation.

关键词： allergy chemokines eosinophils lung mouse

Olfactory Dysfunction as an Early Biomarker in Parkinson's Disease

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Neuroscience Bulletin 2017年第5期33卷 515-525页

作者： Michelle E.fullard james f.Morley John E.Duda Parkinson's Disease Research Education and Clinical Center Corporal Michael J. Crescenz VA Medical CenterPhiladelphia PA 19104 USA Department of Neurology University of Pennsylvania School of Medicine Philadelphia PA 19104 USA

Olfactory dysfunction is common in Parkinson＇s disease （PD） and often predates the diagnosis by years, reflecting early deposition of Lewy pathology, the histo- logic hallmark of PD, in the olfactory bulb. Clinical tests are available that allow for the rapid characterization of olfactory dysfunction, including tests of odor identification, discrimination, detection, and recognition thresholds, memory, and tests assessing the build-up of odor intensity across increasing suprathreshold stimulus concentrations. The high prevalence of olfactory impairment, along with the ease and low cost of assessment, has fostered great interest in olfaction as a potential biomarker for PD. Hyposmia may help differentiate PD from other causes of parkinsonism, and may also aid in the identification of ＂pre-motor＂ PD due to the early pathologic involvement of olfactory pathways. Olfactory function is also correlated with other non-motor features of PD and may serve as a predictor of cognitive decline. In this article, we summarize the existing literature on olfaction in PD, focusing on the potential for olfaction as a biomarker for early or differential diagnosis and prognosis.

关键词： Olfaction · Parkinson's disease · Biomarker ·Parkinsonism · Pathology