| 241. |
- Mazur, Mikael, 1990, et al.
(författare)
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Characterization of Long Multi-Mode Fiber Links using Digital Holography
- 2019
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Ingår i: Optics InfoBase Conference Papers. - 2162-2701.
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Konferensbidrag (refereegranskat)abstract
- We propose to use digital holography to characterize long multi-mode fiber links. A four segment 26.5km fiber span supporting 45 spatial modes is analyzed, showing the evolution of both mode-dependent loss and cross talk.
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| 242. |
- Mazur, Mikael, 1990, et al.
(författare)
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Reduced footprint multiplane light propagation mode multiplexers
- 2019
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Ingår i: IET Conference Publications. ; 2019:CP765
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Konferensbidrag (refereegranskat)abstract
- We design, assemble and characterize three different multiplane light propagation (MPLC)-based mode multiplexers, including a device with reduced size, supporting 45, 45 and 36 spatial modes, respectively. Ranging from 2700 mm3 to 146 mm3, all devices achieve <-12 dB cross talk, showing that MPLC can enable compact multiplexers.
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| 243. |
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| 244. |
- Middleton, Matthew J., et al.
(författare)
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Bright radio emission from an ultraluminous stellar-mass microquasar in M 31
- 2013
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 493:7431, s. 187-190
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Tidskriftsartikel (refereegranskat)abstract
- A subset of ultraluminous X-ray sources (those with luminosities of less than 10(40) erg s(-1); ref. 1) are thought to be powered by the accretion of gas onto black holes with masses of similar to 5-20M(circle dot), probably by means of an accretion disk(2,3). The X-ray and radio emission are coupled in such Galactic sources; the radio emission originates in a relativistic jet thought to be launched from the innermost regions near the black hole(4,5), with the most powerful emission occurring when the rate of infalling matter approaches a theoretical maximum (the Eddington limit). Only four such maximal sources are known in the Milky Way(6), and the absorption of soft X-rays in the interstellar medium hinders the determination of the causal sequence of events that leads to the ejection of the jet. Here we report radio and X-ray observations of a bright new X-ray source in the nearby galaxy M 31, whose peak luminosity exceeded 10(39) erg s(-1). The radio luminosity is extremely high and shows variability on a timescale of tens of minutes, arguing that the source is highly compact and powered by accretion close to the Eddington limit onto a black hole of stellar mass. Continued radio and X-ray monitoring of such sources should reveal the causal relationship between the accretion flow and the powerful jet emission.
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| 245. |
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| 246. |
- Nazemosadat Arsanjani, Seyedeh Bentolhoda, 1984, et al.
(författare)
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Dielectric Broadband Metasurfaces for Fiber Mode-Multiplexed Communications
- 2019
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Ingår i: Advanced Optical Materials. - : Wiley. - 2195-1071. ; 7:14
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Tidskriftsartikel (refereegranskat)abstract
- A subwavelength-thick spatial-mode multiplexer based on a highly transparent all-dielectric Mie-resonant metasurface is demonstrated with a broadband response covering major optical communication wavelength bands. The metasurface is employed to convert simultaneously each orthogonal polarization of LP 01 inputs into individual higher-order TM 01 and TE 01 vectorial modes, without the need of a polarization diversity setup. This is not feasible using current mode multiplexing approaches. An LP 01 polarization-multiplexed 51 × 64 quadrature amplitude modulation (QAM) superchannel, with a 10.3 bits s −1 Hz −1 spectral-efficiency and total bit-rate of 13.2 Tb s −1 , is converted to higher-order modes with the metasurface multiplexer, and then mode-multiplexed data is transmitted over a multimode fiber. The results demonstrate the potential application of these metadevice-based mode multiplexers in space-division multiplexed systems.
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| 247. |
- Nielsen, Rasmus J., et al.
(författare)
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Integrated ecological–economic fisheries models—Evaluation, review and challenges for implementation
- 2018
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Ingår i: Fish and Fisheries. - : Wiley. - 1467-2960 .- 1467-2979. ; 19:1, s. 1-29
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Forskningsöversikt (refereegranskat)abstract
- Marine ecosystems evolve under many interconnected and area-specific pressures. To fulfil society's intensifying and diversifying needs while ensuring ecologically sustainable development, more effective marine spatial planning and broader-scope management of marine resources is necessary. Integrated ecological–economic fisheries models (IEEFMs) of marine systems are needed to evaluate impacts and sustainability of potential management actions and understand, and anticipate ecological, economic and social dynamics at a range of scales from local to national and regional. To make these models most effective, it is important to determine how model characteristics and methods of communicating results influence the model implementation, the nature of the advice that can be provided and the impact on decisions taken by managers. This article presents a global review and comparative evaluation of 35 IEEFMs applied to marine fisheries and marine ecosystem resources to identify the characteristics that determine their usefulness, effectiveness and implementation. The focus is on fully integrated models that allow for feedbacks between ecological and human processes although not all the models reviewed achieve that. Modellers must invest more time to make models user friendly and to participate in management fora where models and model results can be explained and discussed. Such involvement is beneficial to all parties, leading to improvement of models and more effective implementation of advice, but demands substantial resources which must be built into the governance process. It takes time to develop effective processes for using IEEFMs requiring a long-term commitment to integrating multidisciplinary modelling advice into management decision-making.
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| 248. |
- Norström, Albert V., 1979-, et al.
(författare)
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The programme on ecosystem change and society (PECS) - a decade of deepening social-ecological research through a place-based focus
- 2022
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Ingår i: Ecosystems and People. - : Informa UK Limited. - 2639-5908 .- 2639-5916. ; 18:1, s. 598-608
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Tidskriftsartikel (refereegranskat)abstract
- The Programme on Ecosystem Change and Society (PECS) was established in 2011, and is now one of the major international social-ecological systems (SES) research networks. During this time, SES research has undergone a phase of rapid growth and has grown into an influential branch of sustainability science. In this Perspective, we argue that SES research has also deepened over the past decade, and helped to shed light on key dimensions of SES dynamics (e.g. system feedbacks, aspects of system design, goals and paradigms) that can lead to tangible action for solving the major sustainability challenges of our time. We suggest four ways in which the growth of place-based SES research, fostered by networks such as PECS, has contributed to these developments, namely by: 1) shedding light on transformational change, 2) revealing the social dynamics shaping SES, 3) bringing together diverse types of knowledge, and 4) encouraging reflexive researchers.
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| 249. |
- Pace, Michael L., et al.
(författare)
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Whole-lake carbon-13 additions reveal terrestrial support of aquatic food webs
- 2004
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Ingår i: Nature. - : Nature Publishing Group. - 0028-0836 .- 1476-4687. ; 427:6971, s. 240-243
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Tidskriftsartikel (refereegranskat)abstract
- Ecosystems are supported by organic carbon from two distinct sources. Endogenous carbon is produced by photosynthesis within an ecosystem by autotrophic organisms. Exogenous carbon is produced elsewhere and transported into ecosystems. Consumers may use exogenous carbon with consequent influences on population dynamics, predator-prey relationships and ecosystem processes(1). For example, exogenous inputs provide resources that may enhance consumer abundance beyond levels supported by within-system primary production(2). Exogenous fluxes of organic carbon to ecosystems are often large, but this material is recalcitrant and difficult to assimilate, in contrast to endogenously produced organic matter, which is used more easily(3,4). Here we show, by the experimental manipulation of dissolved inorganic C-13 in two lakes, that internal primary production is insufficient to support the food webs of these ecosystems. Additions of NaH (CO3)-C-13 enriched the C-13 content of dissolved inorganic carbon, particulate organic carbon, zooplankton and fish. Dynamics of C-13 indicate that 40-55% of particulate organic carbon and 22-50% of zooplankton carbon are derived from terrestrial sources, showing that there is significant subsidy of these ecosystems by organic carbon produced outside their boundaries.
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| 250. |
- Patrinos, George P., et al.
(författare)
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Human variome project country nodes: Documenting genetic information within a country
- 2012
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Ingår i: Human Mutation. - : Hindawi Limited. - 1059-7794. ; 33:11, s. 1513-1519
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Tidskriftsartikel (refereegranskat)abstract
- The Human Variome Project (http://www.humanvariomeproject.org) is an international effort aiming to systematically collect and share information on all human genetic variation. The two main pillars of this effort are gene/disease-specific databases and a network of Human Variome Project Country Nodes. The latter are nationwide efforts to document the genomic variation reported within a specific population. The development and successful operation of the Human Variome Project Country Nodes are of utmost importance to the success of Human Variome Project's aims and goals because they not only allow the genetic burden of disease to be quantified in different countries, but also provide diagnosticians and researchers access to an up-to-date resource that will assist them in their daily clinical practice and biomedical research, respectively. Here, we report the discussions and recommendations that resulted from the inaugural meeting of the International Confederation of Countries Advisory Council, held on 12th December 2011, during the 2011 Human Variome Project Beijing Meeting. We discuss the steps necessary to maximize the impact of the Country Node effort for developing regional and country-specific clinical genetics resources and summarize a few well-coordinated genetic data collection initiatives that would serve as paradigms for similar projects. Hum Mutat 33:15131519, 2012. (c) 2012 Wiley Periodicals, Inc.
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