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Self-configuring universal linear optical component[Invited]

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Photonics Research 2013年第1期1卷 1-15页

作者： david a.b.miller Ginzton Laboratory Stanford University348 Via Pueblo MallStanfordCalifornia 94305-4088USA

We show how to design an optical device that can perform any linear function or coupling between inputs and *** design method is progressive,requiring no global *** also show how the device can configure itself progressively,avoiding design calculations and allowing the device to stabilize itself against drifts in component properties and to continually adjust itself to changing *** self-configuration operates by training with the desired pairs of orthogonal input and output functions,using sets of detectors and local feedback loops to set individual optical elements within the device,with no global feedback or multiparameter optimization *** mappings,such as spatial mode conversions and polarization control,can be implemented using standard planar integrated *** the spirit of a universal machine,we show that other linear operations,including frequency and time mappings,as well as nonreciprocal operation,are possible in principle,even if very challenging in practice,thus proving there is at least one constructive design for any conceivable linear optical component;such a universal device can also be *** approach is general for linear waves,and could be applied to microwaves,acoustics,and quantum mechanical superpositions.

关键词： acoustics operations optics

Separating arbitrary free-space beams with an integrated photonic processor

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Light(Science & Applications) 2022年第8期11卷 1811-1822页

作者： Maziyar Milanizadeh SeyedMohammad SeyedinNavadeh Francesco Zanetto Vittorio Grimaldi Christian De Vita Charalambos Klitis Marc Sorel Giorgio Ferrari david a.b.miller Andrea Melloni Francesco Morichetti Department of Electronics Information and BioengineeringPolitecnico di Milanovia Ponzio 34/520133MilanoItaly School of Engineering University of GlasgowGlasgowG128QQUK TeCIP Institute Scuola Superiore Sant’Anna56124PisaItaly Ginzton Laboratory Stanford UniversitySpilker BuildingStanfordCA94305USA

Free-space optics naturally offers multiple-channel communications and sensing exploitable in many applications. The different optical beams will, however, generally be overlapping at the receiver, and, especially with atmospheric turbulence or other scattering or aberrations, the arriving beam shapes may not even be known in advance. We show that such beams can be still separated in the optical domain, and simultaneously detected with negligible cross-talk, even if they share the same wavelength and polarization, and even with unknown arriving beam shapes. The kernel of the adaptive multibeam receiver presented in this work is a programmable integrated photonic processor that is coupled to free-space beams through a two-dimensional array of optical antennas. We demonstrate separation of beam pairs arriving from different directions, with overlapping spatial modes in the same direction, and even with mixing between the beams deliberately added in the path. With the circuit’s optical bandwidth of more than 40 nm, this approach offers an enabling technology for the evolution of FSO from single-beam to multibeam space-division multiplexed systems in a perturbed environment, which has been a game-changing transition in fiber-optic systems.

关键词： processor polarization scattering

Coherent self-control of free-space optical beams with integrated silicon photonic meshes

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Photonics Research 2021年第11期9卷 2196-2204页

作者： MAZIYAR MILANIZADEH FAbIO TOSO GIORGIO FERRARI TIGERS JONUZI david a.b.miller ANDREA MELLONI FRANCESCO MORICHETTI Dipartimento di Elettronica Informazione e Bioingegneria-Politecnico di MilanoMilano 20133Italy VLC Photonics Universidad Politecnica de Valencia46022 ValenciaSpain Ginzton Laboratory Stanford UniversityStanfordCalifornia 94305USA

In technologies operating at light wavelengths for wireless communication,sensor networks,positioning,and ranging,a dynamic coherent control and manipulation of light fields is an enabling element for properly generating and correctly receiving free-space optical(FSO)beams even in the presence of unpredictable objects and turbulence in the light *** this work,we use a programmable mesh of Mach-Zehnder(MZI)interferometers to automatically control the complex field radiated and captured by an array of optical *** implementation of local feedback control loops in each MZI stage,without global multivariable optimization techniques,enables an unlimited *** functionalities are demonstrated,including the generation of perfectly shaped beams with nonperfect optical antennas,the imaging of a desired field pattern through an obstacle or a diffusive medium,and the identification of an unknown obstacle inserted in the FSO *** to conventional devices used for the manipulation of FSO beams,such as spatial light modulators,our programmable device can self-configure through automated control strategies and can be integrated with other functionalities implemented onto the same photonic chip.

关键词： optical interferometer obstacle

Metal-dielectric-metal plasmonic waveguide devices for manipulating light at the nanoscale

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Chinese Optics Letters 2009年第4期7卷 302-308页

作者： Georgios Veronis Zongfu Yu Sukru Ekin Kocaba david A. b. miller Mark L. brongersma Shanhui Fan Department of Electrical and Computer Engineering and Center for Computation and Technology Louisiana State University Baton Rouge LA 70803 USA Ginzton LaSoratory Stanford University Stanford CA 94305 USA GeSalle LaSoratory of Advanced Materials Stanford University Stanford CA 94305 USA

We review some of the recent advances in the development of subwavelength plasmonic devices for manipulating light at the nanoseale, drawing examples from our own work in metal-dielectric-metal （MDM） plasmonic waveguide devices. We introduce bends, splitters, and mode converters for MDM waveguides with no additional loss. We also demonstrate that optical gain provides a mechanism for on/off switching in MDM plasmonic waveguides. Highly efficient compact couplers between dielectric waveguides and MDM waveguides are also introduced.

关键词： Metals Multiplexing Nanotechnology Optical waveguides Plasmons Waveguide components Waveguides

Neuroinflammation revisited through the microglial lens

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Neural Regeneration Research 2025年第7期20卷 1989-1990页

作者： Renato Socodato João b.Relvas Institute of Research and Innovation in Health(i3S)and Institute for Molecular and Cell biology(IbMC) University of PortoPortoPortugal Department of biomedicine Faculty of Medicine of the University of Porto(FMUP)PortoPortugal

Neuroimmunology is emerging as a pivotal field,shedding light on the intricate dialogues between the central nervous system(CNS)and the immune *** exploration is particularly significant in understanding microglia,the CNS’s innate immune cells,beyond the conventional conflation of“neuroinflammation”and“microglial activation.”This conflation has clouded the true complexity of these processes,potentially stalling scientific progress and the development of new *** challenge the long-standing perspectives that have oversimplified these interactions,advocating for a deeper exploration of the dynamic relationship between neuroinflammation and microglial *** dissecting specific molecular pathways,we aim to illuminate their elaborate roles in neuroinflammatory responses,especially in the context of Alzheimer’s disease(AD).Here,neuroinflammation is not merely a passive observer or a direct antagonist but a complex agent in the disease’s *** article calls for a significant paradigm shift towards an integrative,multi-omics approach to *** such a comprehensive framework is crucial for advancing our understanding of neuroinflammatory conditions and paving the way for targeted therapeutic strategies for brain diseases.

关键词： inflammation simplified activation

Design of synthetic materials for intracellular delivery of RNAs： From siRNA-mediated gene silencing to CRISPR/Cas gene editing

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Nano Research 2018年第10期11卷 5310-5337页

作者： Jason b. miller Daniel J. Siegwart Simmons Comprehensive Cancer Center University of Texas Southwestern Medical Center Dallas TX 75390 USA Department of biochemistry University of Texas Southwestern Medical Center Dallas TX 75390 USA

Ribonucleic acids （RNAs） possess great therapeutic potential and can be used to treat a variety of diseases. The unique biophysical properties of RNAs, such as high molecular weight, negative charge, hydrophilicity, low stability, and potential immunogenicity, require chemical modification and development of carriers to enable intracellular delivery of RNAs for clinical use. A variety of nanornaterials have been developed for the effective in vivo delivery of short/ small RNAs, messenger RNAs, and RNAs required for gene editing technologies including clustered regularly interspaced palindromic repeat （CRISPR）/Cas. This review outlines the challenges of delivering RNA therapeutics, explores the chemical synthesis of RNA modifications and carriers, and describes the efforts to design nanomaterials that can be used for a variety of clinical indications.

关键词： nucleic acid therapeutics nanoparticles synthetic nanomaterials RNA interference (RNAi) messenger RNA (mRNA) clustered regularly inter-spaced palindromic repeat(CRISPR)/Cas

A matter of time： Temporal variation in the introduction history and population genetic structuring of an invasive lizard

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Current Zoology 2015年第3期61卷 456-464页

作者： HalmahMOULE Kirilee CHAPLIN Rebecca D. bRAY Kimberly A. miller Michael b. THOMSON david G. CHAPPLE School of biological Sciences Monash University Clayton Victoria 3800 Australia Department of Sciences Museum Victoria Victoria 3001 Australia School of biological Sciences University of Sydney Sydney NSW 2006 Australia Allan Wilson Centre for Molecular Ecology and Evolution School of Biological Sciences Victoria University of Wellington Wellington 6140 New Zealand

Invasive species are considered one of the greatest threats to native ecosystems, second only to habitat loss and frag- mentation. Despite this, the temporal dynamics of invasions are poorly understood, with most studies focusing on a single time point, providing us with only a snapshot of the biology and genetics of the invader. We investigated the invasion of Lord Howe Island by the delicate skink Lampropholis delicata and assessed the introduction history and genetic structure of this species over a 5-year period. Using genetic data taken from 2007, and again in 2011/12, we examined changes in the population genetic struc- ture （whether new haplotypes had been introduced to the island, and shifts in haplotype frequencies） of the species on the island between these two time points. No new haplotypes were introduced to the island between 2007 and 2011/12; however, significant shifts in haplotype frequencies across the island were detected. We conclude that the delicate skink is expanding its range into the southern regions of the island and that the haplotype frequencies on Lord Howe Island are still in a state of highly dynamic flux. Our study highlights the importance of considering invasions as dynamic and studying them in such a way that enable us to better manage their impacts

关键词： biological invasion Genetic admixture Lampropholis delicata Lord Howe Island Population genetics,Unintentional introduction

Intraspecific temporal resource partitioning at white-tailed deer feeding sites

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Current Zoology 2019年第2期65卷 139-146页

作者： david b. STONE James A. MARTIN bradley S. COHEN Thomas J. PREbYL Charlie KILLMASTER Karl V. miller Warnell School of Forestry and Natural Resources University of Georgia Athens GA USA Savannah River Ecology Lab University of Georgia Aiken SC USA Department of biology Tennessee Technological University Cookeville TN USA Georgia Department of Natural Resources Atlanta GA USA

Individuals may reduce competition by temporally partitioning their use of a shared resource. behavioral differences between sexes in ungulates may encourage segregation as individuals attempt to avoid antagonistic interactions. However, dominant sex and age groups may reduce subordinates' access to food resources, regardless of the subordinate's sex. We hypothesized that white-tailed deer Odocoileus Virginian us temporally segregated at supplemental feedi ng sites based on social rank (subordinate: yearling males and adult females;dominant: adult males) and that segregation was affected by phase of the breeding season and diel cycle. If deer temporally segregate according to social rank, we predicted that the resulting activity patterns would manifest in one social class being relatively more susceptible to hunter-induced mortality. We used a multistate modeling approach to quantify temporal segregation and calculated the probability that a feeding site was in a particular state during diurnal and nocturnal hours for each of the 3 phases of the breeding season. We determined that transition probabilities differed by season and diel cycle and dominant and subordinate social classes clearly avoided each other, with breedi ng seas on, the probability of a subordi nate being present during diurnal hours was *** more likely than a dominant being present, but did not differ during nocturnal hours. There was no difference for dominants and subordinates during diurnal or no cturnal hours during the breedi ng season .In the post-breedi ng season, subordi nates were 1.7x more likely to occur at the feeding site than a dominant during diurnal hours but they did not differ during nocturnal hours. Our results indicate that dominance status influences temporal segregation at feeding sites and is affected by the phase of the breeding season. Therefore, the resulti ng activity patterns may in crease subordi nates' risk to human

关键词： competition multistate modeling predation risk supplemental feeding sites intraspecific temporal resource partitioning white-tailed deer

Variations in zonal fruit starch concentrations of apples – a developmental phenomenon or an indication of ripening?

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Horticulture Research 2015年第1期2卷 84-92页

作者： Franziska C Doerflinger William b miller Jacqueline F Nock Christopher b Watkins Horticulture Section School of Integrative Plant ScienceCornell UniversityIthaca14853NYUSA School of Agriculture Food&WineUniversity of AdelaideWaite CampusGlen Osmond5064South AustraliaAustralia

Patterns of starch hydrolysis in stem,equatorial,and calyx zones of‘Honeycrisp’and‘Empire’apples(Malus sylvestris(L.)Mill ***(borkh.)Mansf.)during maturation and ripening,and in‘Gala’apples in response to propylene or 1-methylcyclopropene(1-MCP)treatments after harvest,were *** in zonal starch concentrations were found for‘Empire’and‘Gala’fruits,but not for‘Honeycrisp’.During maturation and ripening of‘Empire’,the concentration of starch was highest in the calyx end and lowest in the stem region.Differences in rates of starch hydrolysis among zones were not detected.‘Honeycrisp’and‘Empire’had the highest concentration of sorbitol in the calyx region,whereas it was highest in the stem-end region in‘Gala’.The distribution differences of glucose,fructose,and sucrose were similar in all three cultivars;higher fructose and glucose concentrations in the stem region,and higher sucrose concentrations in the calyx end of the *** treatment of‘Gala’with propylene did not affect the internal ethylene concentration of the fruit but 1-MCP markedly inhibited *** concentrations were highest in the calyx end but gradients of starch among zones were not changed by postharvest *** rate of hydrolysis was slowed by 1-MCP treatment,but was unaffected by *** treatments influenced sorbitol,glucose,and fructose *** of starch concentration among the zones did not confirm differences in ripening,but reflected its uneven distribution throughout the fruit during ***,measured differences in zonal starch are most likely related to starch accumulation during fruit development,rather than differences in rates of starch degradation during ripening.

关键词： cultivar fir starch