The Recognition of Fires Originating from Photovoltaic (PV) Solar Systems

There has been an observable increase in the fitting of photovoltaic (PV) solar panels on the roofs of buildings in the UK over the last decade. The origin of some fires in domestic and commercial properties has been attributed to PV systems. This thesis examines the ability of fire examiners to recognise and record details of fires believed to have originated from PV systems, as well as investigating the effect of internal heating in direct current (DC) isolators to the point at which they fail. National fire data was examined along with the methods for collecting and collating these data. This clarified that national fire data cannot identify the specifics of electrical fires. Validity of these data was then tested by identifying the confidence and competence in the recognition of the origin of fire, (especially when associated with PV systems), of some fire staff responsible for collecting fire data. This suggests that some fire scenes examiners are not confident in their own ability to recognise fires originating from PV systems. Evidence for fires occurring in PV systems in Kent between 2009 and 2014 was then examined, including a cold case forensic review of the evidence. This provided an indication that a potential common point of failure, which may lead to fire originating from a PV system, was to be found within the DC section of the PV circuits and probably within the DC isolator switch itself. Experimentation revealed that internal heating of a terminal connection can lead to changes of the phase of the insulating material, causing failure of structural integrity and therefore allowing an arc to be established. Observable post fire indicators associated with this mechanism of failure have been identified as well as hydrocarbons evolved from pyrolysis of isolator insulating material. Finally, areas for further experimental research and training of fire staff are suggested as well as the modification of recording mechanisms and building regulations

Principles, fundamentals, and applications of programmable integrated photonics

[EN] Programmable integrated photonics is an emerging new paradigm that aims at designing common integrated optical hardware resource configurations, capable of implementing an unconstrained variety of functionalities by suitable programming, following a parallel but not identical path to that of integrated electronics in the past two decades of the last century. Programmable integrated photonics is raising considerable interest, as it is driven by the surge of a considerable number of new applications in the fields of telecommunications, quantum information processing, sensing, and neurophotonics, calling for flexible, reconfigurable, low-cost, compact, and low-power-consuming devices that can cooperate with integrated electronic devices to overcome the limitation expected by the demise of Moore¿s Law. Integrated photonic devices exploiting full programmability are expected to scale from application-specific photonic chips (featuring a relatively low number of functionalities) up to very complex application-agnostic complex subsystems much in the same way as field programmable gate arrays and microprocessors operate in electronics. Two main differences need to be considered. First, as opposed to integrated electronics, programmable integrated photonics will carry analog operations over the signals to be processed. Second, the scale of integration density will be several orders of magnitude smaller due to the physical limitations imposed by the wavelength ratio of electrons and light wave photons. The success of programmable integrated photonics will depend on leveraging the properties of integrated photonic devices and, in particular, on research into suitable interconnection hardware architectures that can offer a very high spatial regularity as well as the possibility of independently setting (with a very low power consumption) the interconnection state of each connecting element. Integrated multiport interferometers and waveguide meshes provide regular and periodic geometries, formed by replicating unit elements and cells, respectively. In the case of waveguide meshes, the cells can take the form of a square, hexagon, or triangle, among other configurations. Each side of the cell is formed by two integrated waveguides connected by means of a Mach¿Zehnder interferometer or a tunable directional coupler that can be operated by means of an output control signal as a crossbar switch or as a variable coupler with independent power division ratio and phase shift. In this paper, we provide the basic foundations and principles behind the construction of these complex programmable circuits. We also review some practical aspects that limit the programming and scalability of programmable integrated photonics and provide an overview of some of the most salient applications demonstrated so far.European Research Council; Conselleria d'Educació, Investigació, Cultura i Esport; Ministerio de Ciencia, Innovación y Universidades; European Cooperation in Science and Technology; Horizon 2020 Framework Programme.Pérez-López, D.; Gasulla Mestre, I.; Dasmahapatra, P.; Capmany Francoy, J. (2020). Principles, fundamentals, and applications of programmable integrated photonics. Advances in Optics and Photonics. 12(3):709-786. https://doi.org/10.1364/AOP.387155709786123Lyke, J. C., Christodoulou, C. G., Vera, G. A., & Edwards, A. H. (2015). An Introduction to Reconfigurable Systems. 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Multipurpose self-configuration of programmable photonic circuits

[EN] Programmable integrated photonic circuits have been called upon to lead a new revolution in information systems by teaming up with high speed digital electronics and in this way, adding unique complementary features supported by their ability to provide bandwidthunconstrained analog signal processing. Relying on a common hardware implemented by two-dimensional integrated photonic waveguide meshes, they can provide multiple functionalities by suitable programming of their control signals. Scalability, which is essential for increasing functional complexity and integration density, is currently limited by the need to precisely control and configure several hundreds of variables and simultaneously manage multiple configuration actions. Here we propose and experimentally demonstrate two different approaches towards management automation in programmable integrated photonic circuits. These enable the simultaneous handling of circuit self-characterization, auto-routing, self-configuration and optimization. By combining computational optimization and photonics, this work takes an important step towards the realization of high-density and complex integrated programmable photonics.D.P.L. acknowledges funding through the Spanish MINECO Juan de la Cierva program. J.C. acknowledges funding from the ERC Advanced Grant ERC-ADG-2016-741415 UMWP-Chip and ERC-2019-POC-859927. Authors also acknowledge funding from Future MWP technologies and applications PROMETEO/2017/103, Advanced Instrumentation for World Class Microwave Photonics Research IDIFEDER/2018/031, EUIMWP CA16220, Infraestructura para caracterizacion de Chips Fotonicos EQC2018-004683-P.Pérez-López, D.; López-Hernández, A.; Dasmahapatra, P.; Capmany Francoy, J. (2020). Multipurpose self-configuration of programmable photonic circuits. Nature Communications. 11(1):1-11. https://doi.org/10.1038/s41467-020-19608-w111111Chrostowski, L. & Hochberg, M. Silicon Photonics Design (Cambridge University Press, 2015).Lin, Y. et al. Characterization of hybrid InP-TriPleX photonic integrated tunable lasers based on silicon nitride (Si 3N4/SiO2) microring resonators for optical coherent system. IEEE Photonics J. 10, 1400108 (2018).Bogaerts, W. et al. Proc. Integrated Design for Integrated Photonics: from the Physical to the Circuit Level and Back (SPIE Optics and Optoelectronics, Prague, Czech Republic, 2013).Inniss, D. & Rubenstein, R. Silicon Photonics: Fueling the Next Information Revolution (Elsevier Science, 2016).Streshinsky, M. et al. The road to affordable, large-scale silicon photonics. Opt. Photonics News 24, 32–39, (2013).Carrol, L. et al. Photonic packaging: transforming silicon photonic integrated circuits into photonic devices. Appl. Sci. 6, 426 (2016).Capmany, J. & Pérez, D. Programmable Integrated Photonics (Oxford University Press, 2019).Lyke, J. et al. An introduction to reconfigurable systems. Proc. IEEE 103, 291–317 (2015).Capmany, J., Gasulla, I. & Pérez, D. The programmable processor. Nat. Photonics 10, 6–8 (2015).Carolan, J. et al. Universal linear optics. Science 349, 711 (2015).Ribeiro, A. et al. Demonstration of a 4×4-port universal linear circuit. Optica 3, 1348–1357 (2016).Annoni, A. Unscrambling light—automatically undoing strong mixing between modes. Light Sci. Appl. 6, e17110 (2017).Shen, Y. et al. Deep learning with coherent nanophotonic circuits. Nat. Photonics 11, 441–446 (2017).Mennea, P. L. et al. Modular linear optical circuits. Optica 5, 1087–1090 (2018).Zheng, D. et al. Low-loss broadband 5×5 non-blocking Si3N4 optical switch matrix. Opt. Lett. 44, 2629–2632 (2019).Zhuang, L. et al. Programmable photonic signal processor chip for radiofrequency applications. Optica 2, 854–859 (2015).Pérez, D. et al. Multipurpose silicon photonics signal processor core. Nat. Commun. 8, 636 (2017).Zhang, W. & Yao, J. Photonic integrated field-programmable disk array signal processor. Nat. Commun. 11, 406 (2020).Eberhart, J. K. R. A new optimizer using particle swarm theory. In MHS'95. Proceedings of the Sixth International Symposium on Micro Machine and Human Science (IEEE, Nagoya, Japan, 1995).Whitley, D. A genetic algorithm tutorial. Stat. Comput. 4, 65–85 (1994).Zibar, D., Wymeersch, H. & Lyubomirsky, I. Machine Learning under the spotlight. Nat. Photonics 11, 749–751 (2017).Pérez, D. Programmable integrated silicon photonics waveguide meshes: optimized designs and control algorithms. In IEEE Journal of Selected Topics in Quantum Electronics, Vol. 26 (IEEE, 2019).Pérez, D., Gasulla, I. & Capmany, J. Field-programmable photonic arrays. Opt. Express 26, 27265–27278 (2018).Pérez, D., Gasulla, I., Soref, R. & Capmany, J. Reconfigurable lattice mesh designs for programmable photonic processors. Opt. Express 24, 12093–12106 (2016).Pérez-López, D., Sánchez, E. & Capmany, Y. J. Programmable true time delay lines using integrated waveguide meshes. J. Lightwave Technol. 36, 4591–4601 (2018).López, A. et al. Auto-routing algorithm for field-programmable photonic gate arrays. Opt. Express 28, 737–752 (2020).Chen, X. & Boggaerts, W. A graph-based design and programming strategy for reconfigurable photonic circuits. In IEEE Photonics Society Summer Topical Meeting Series (SUM) (IEEE, Fort Lauderdale, FL, USA, 2019).Pérez, D., López, A., DasMahapatra, P. & Capmany, J. Field-Programmable Photonic Array for multipurpose microwave photonic applications. In IEEE International Topical Meeting on Microwave Photonics (MWP) (IEEE, Ottawa, Canada, 2019).Pérez, D. & Capmany, J. Scalable analysis for arbitrary photonic integrated waveguide meshes. Optica 6, 19–27 (2019).Yegnanarayanan, S. et al. Automated initialization of reconfigurable silicon-nitride (SiNx) filters. In Conference on Lasers and Electro-Optics (IEEE, San José, CA, 2018).Milanizadeh, M. et al. Cancelling thermal cross-talk effects in photonic integrated circuits. J. Light. Tech. 37, 1325–1332 (2019).Xie, Y., Zhuang, L. & Lowery, A. J. Picosecond optical pulse processing using a terahertz-bandwidth reconfigurable photonic integrated circuit. Nanophotonics 7, 837–852 (2018).Guan, B. et al. CMOS compatible reconfigurable silicon photonic lattice filters using cascaded unit cells for RF-photonic processing. IEEE J. Sel. Top. Quantum Electron. 20, 359–368 (2014).Doylend, J. K. et al. Hybrid III/V silicon photonic source with integrated 1D free-space beam steering. Opt. Lett. 37, 4257–4259 (2012).Burla, M. Advanced integrated optical beam forming networks for broadband phased array antenna systems, Telecommunication Engineering Faculty of Electrical Engineering, Mathematics and Computer Science. PhD. Thesis, University of Twente (2013).Wang, J. et al. Reconfigurable radio-frequency arbitrary waveforms synthesized in a silicon photonic chip, Nat. Commun. 6, 5957 (2015).Dumais, P. et al. Silicon photonic switch subsystem with 900 monolithically integrated calibration photodiodes and 64-fiber package. J. Lightwave Technol. 36, 233–238 (2018).Tanizawa, K. et al. 32×32 strictly non-blocking Si-wire optical switch on ultra-small die of 11×25 mm2. In Optical Fiber Communications Conference (IEEE, Los Angeles, CA, USA, 2015).Miller, D. A. B. Perfect optics with imperfect components. Optica 2, 747–750 (2015).Gazman, A. et al. Tapless and topology agnostic calibration solution for silicon photonic switches. Opt. Express 26, 347241 (2018).Cheng, Q. et al. First demonstration of automated control and assessment of a dynamically reconfigured monolithic 8 × 8 wavelength-and-space switch. IEEE J. Opt. Commun. Netw. 7, 388–395 (2015).Tait, A. N. et al. Continuous calibration of microring weights for analog optical networks. IEEE Photonics Technol. Lett. 28, 887–890 (2016).Carolan, J. et al. Scalable feedback control of single photon sources for photonic quantum technologies. Optica 6, 335–341 (2019).Tait, A. N. et al. Multi-channel control for microring weightbanks. Opt. Express 24, 8895 (2016).Jiang, H. et al. Chip-based arbitrary radio-frequency photonic filter with algorithm-driven reconfigurable resolution. Opt. Lett. 43, 415–418 (2018).Jayatilleka, H. Automatic configuration and wavelength locking of coupled silicon ring resonators. J. Lightwave Technol. 36, 210–218 (2018).Choo, G. Automatic monitor-based tuning of reconfigurable silicon photonic APF-based pole/zero filters. J. Lightwave Technol. 36, 1899–1911 (2018).Choo, G. Automatic monitor-based tuning of an RF silicon photonic 1X4 asymmetric binary tree true-time-delay beamforming network. J. Lightwave Technol. 36, 5263–5275 (2018).Bin Mohd Zain, M. Z. et al. A multi-objective particle swarm optimization algorithm based on dynamic boundary search for constrained optimization. Appl. Soft Comput. 70, 680–700 (2018).Pérez, D. et al. Thermal tuners on a silicon nitride platform. Preprint at https://arxiv.org/abs/1604.02958 (2016)

Modeling amplified arbitrary filtered microwave photonic links and systems

[EN] Microwave photonic (MWP) links and systems will have more losses as their complexities increase and there will be a need for incorporating optical amplification. Here, we report results of an analytical model developed for amplified arbitrary filtered MWP systems that provides the expressions of the main figures of merit fur intensity modulation direct detection. It contemplates the cases of power, intermediate and pre amplification. The model is applied to a long MWP link and then it is evaluated in a MWP reconfigurable filter implemented by means of a programmable waveguide mesh photonic integrated circuit.Ministerio de Ciencia, Innovacion y Universidades (JUANDELACIERVAAWARD); European Commission (H2020-ICT-2019-021-871330 NEOTERIC); Generalitat Valenciana (IDIFEDER/2018/031, IDIFEDER/2020/032, PROMETEO/2017/103); European Research Council (ERC ADG-2016-741415 UMWP-Chip, ERC-POC-2019-859927).Sánchez-Gomáriz, E.; Pérez-López, D.; Dasmahapatra, P.; Capmany Francoy, J. (2021). Modeling amplified arbitrary filtered microwave photonic links and systems. Optics Express. 29(10):14757-14772. https://doi.org/10.1364/OE.423613S1475714772291

Dual-Drive Directional Couplers for Programmable Integrated Photonics

A novel class of photonic integrated circuits employs large-scale integration of combined beam splitters and waveguides loaded with phase actuators to provide complex linear processing functionalities that can be reconfigured dynamically. Here, we propose and experimentally demonstrate a thermally-actuated Dual-Drive Directional Coupler (DD-DC) design, integrated in a silicon nitride platform, functioning both as a standalone optical component providing arbitrary optical beam splitting and common phase as well as for its use in waveguide mesh arrangements. We analyze the experimental demonstration of the first integration of a triangular waveguide mesh arrangement, and the first DD-DC based arrangement along with an extended analysis of its performance and scalability

Auto-routing algorithm for field-programmable photonic gate arrays

[EN] Programmable multipurpose photonic integrated circuits require software routines to make use of their flexible operation as desired. In this work, we propose and demonstrate the use of a modified tree-search algorithm to automatically determine the optimum optical path in a field-programmable photonic gate array (FPPGA), based on end-user specifications, circuit architecture and imperfections in the realized FPPGA arising, for example, from fabrication variations. In such a scenario, the proposed algorithm only requires the hardware topology and the location of the connections of the FPPGA defining the optical path to be programmed. The routine is able to optimize the path over multiple and competing objectives like the overall length, accumulated loss and power consumption. In addition, should any region of the circuit suffer from any potential damage that may affect the device performance, this algorithm is also able to provide basic self-healing and fault-tolerance capabilities by supplying alternative paths through the photonic arrangement.The authors acknowledge financial support by the ERC ADG-2016 UMWP-Chip ERC-2016- ADG-741415, the ERC PoC-2019 FPPAs ERC-2019-POC-859927, the Generalitat Valenciana Future MWP technologies and applications PROMETEO 2017/103 research excellency award, and the COST Action CA16220 EUIMWP, the Advanced Instrumentation for World Class Microwave Photonics Research IDIFEDER/2018/031 and the Infraestructura para caracterizacion de Chips Fotonicos EQC2018-004683-PLópez-Hernández, A.; Pérez-López, D.; Dasmahapatra, P.; Capmany Francoy, J. (2020). Auto-routing algorithm for field-programmable photonic gate arrays. Optics Express. 28(1):737-752. https://doi.org/10.1364/oe.382753737752281Soref, R. (2006). The Past, Present, and Future of Silicon Photonics. IEEE Journal of Selected Topics in Quantum Electronics, 12(6), 1678-1687. doi:10.1109/jstqe.2006.883151Streshinsky, M., Ding, R., Liu, Y., Novack, A., Galland, C., Lim, A. E.-J., … Hochberg, M. (2013). The Road to Affordable, Large-Scale Silicon Photonics. Optics and Photonics News, 24(9), 32. doi:10.1364/opn.24.9.000032Smit, M., Leijtens, X., Ambrosius, H., Bente, E., van der Tol, J., Smalbrugge, B., … van Veldhoven, R. (2014). An introduction to InP-based generic integration technology. Semiconductor Science and Technology, 29(8), 083001. doi:10.1088/0268-1242/29/8/083001Carroll, L., Lee, J.-S., Scarcella, C., Gradkowski, K., Duperron, M., Lu, H., … O’Brien, P. (2016). Photonic Packaging: Transforming Silicon Photonic Integrated Circuits into Photonic Devices. Applied Sciences, 6(12), 426. doi:10.3390/app6120426Pérez, D., Gasulla, I., & Capmany, J. (2018). Field-programmable photonic arrays. Optics Express, 26(21), 27265. doi:10.1364/oe.26.027265Pérez, D., Gasulla, I., Capmany, J., & Soref, R. A. (2016). Reconfigurable lattice mesh designs for programmable photonic processors. Optics Express, 24(11), 12093. doi:10.1364/oe.24.012093Zhuang, L., Roeloffzen, C. G. H., Hoekman, M., Boller, K.-J., & Lowery, A. J. (2015). Programmable photonic signal processor chip for radiofrequency applications. Optica, 2(10), 854. doi:10.1364/optica.2.000854Pérez, D., Gasulla, I., Crudgington, L., Thomson, D. J., Khokhar, A. Z., Li, K., … Capmany, J. (2017). Multipurpose silicon photonics signal processor core. Nature Communications, 8(1). doi:10.1038/s41467-017-00714-1Pérez, D., & Capmany, J. (2019). Scalable analysis for arbitrary photonic integrated waveguide meshes. Optica, 6(1), 19. doi:10.1364/optica.6.000019Dijkstra, E. W. (1959). A note on two problems in connexion with graphs. Numerische Mathematik, 1(1), 269-271. doi:10.1007/bf01386390McQuillan, J., Richer, I., & Rosen, E. (1980). The New Routing Algorithm for the ARPANET. IEEE Transactions on Communications, 28(5), 711-719. doi:10.1109/tcom.1980.109472

Integrated photonic tunable basic units using dual-drive directional couplers

"© 2019 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited"[EN] Photonic integrated circuits based on waveguide meshes and multibeam interferometers call for large-scale integration of Tunable Basic Units (TBUs) that feature beam splitters and waveguides. This units are loaded with phase actuators to provide complex linear processing functionalities based on optical interference and can be reconfigured dynamically. Here, we propose and experimentally demonstrate, to the best of our knowledge, for the first time, a thermally actuated Dual-Drive Directional Coupler (DD-DC) design integrated on a silicon nitride platform. It operates both as a standalone optical component providing arbitrary optical beam splitting and common phase as well as a low loss and potentially low footprint TBU. Finally, we report the experimental demonstration of the first integrated triangular waveguide mesh arrangement using DD-DC based TBUs and provide an extended analysis of its performance and scalability. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing AgreementEuropean Research Council (ERC ADG-2016UMWP-Chip, ERC-POC-2019 FPPAs); Generalitat Valenciana (PROMETEO 2017/017); European Cooperation in Science and Technology (COST Action CA16220 EUIMWP.).Pérez-López, D.; Gutierrez Campo, AM.; Sánchez-Gomáriz, E.; Dasmahapatra, P.; Capmany Francoy, J. (2019). Integrated photonic tunable basic units using dual-drive directional couplers. Optics Express. 27(26):38071-38086. https://doi.org/10.1364/OE.27.03807138071380862726Soref, R. (2006). The Past, Present, and Future of Silicon Photonics. IEEE Journal of Selected Topics in Quantum Electronics, 12(6), 1678-1687. doi:10.1109/jstqe.2006.883151Somekh, S., Garmire, E., Yariv, A., Garvin, H. L., & Hunsperger, R. G. (1974). Channel Optical Waveguides and Directional Couplers in GaAs–Imbedded and Ridged. Applied Optics, 13(2), 327. doi:10.1364/ao.13.000327Pérez, D., Gasulla, I., Capmany, J., & Soref, R. A. (2016). Reconfigurable lattice mesh designs for programmable photonic processors. Optics Express, 24(11), 12093. doi:10.1364/oe.24.012093Clements, W. R., Humphreys, P. C., Metcalf, B. J., Kolthammer, W. S., & Walsmley, I. A. (2016). Optimal design for universal multiport interferometers. Optica, 3(12), 1460. doi:10.1364/optica.3.001460Zhuang, L., Roeloffzen, C. G. H., Hoekman, M., Boller, K.-J., & Lowery, A. J. (2015). Programmable photonic signal processor chip for radiofrequency applications. Optica, 2(10), 854. doi:10.1364/optica.2.000854Pérez, D., Gasulla, I., Crudgington, L., Thomson, D. J., Khokhar, A. Z., Li, K., … Capmany, J. (2017). Multipurpose silicon photonics signal processor core. Nature Communications, 8(1). doi:10.1038/s41467-017-00714-1Perez-Lopez, D., Sanchez, E., & Capmany, J. (2018). Programmable True Time Delay Lines Using Integrated Waveguide Meshes. Journal of Lightwave Technology, 36(19), 4591-4601. doi:10.1109/jlt.2018.2831008Kogelnik, H., & Schmidt, R. (1976). Switched directional couplers with alternating ΔΒ. IEEE Journal of Quantum Electronics, 12(7), 396-401. doi:10.1109/jqe.1976.1069190Schmidt, R. V., & Kogelnik, H. (1976). Electro‐optically switched coupler with stepped Δβ reversal using Ti‐diffused LiNbO3waveguides. Applied Physics Letters, 28(9), 503-506. doi:10.1063/1.88833Alferness, R. C., & Veselka, J. J. (1985). Simultaneous modulation and wavelength multiplexing with a tunable Ti:LiNbO3directional coupler filter. Electronics Letters, 21(11), 466-467. doi:10.1049/el:19850330Sharkawy, A., Shi, S., Prather, D. W., & Soref, R. A. (2002). Electro-optical switching using coupled photonic crystal waveguides. Optics Express, 10(20), 1048. doi:10.1364/oe.10.001048Orlandi, P., Morichetti, F., Strain, M. J., Sorel, M., Melloni, A., & Bassi, P. (2013). Tunable silicon photonics directional coupler driven by a transverse temperature gradient. Optics Letters, 38(6), 863. doi:10.1364/ol.38.000863Pérez, D., & Capmany, J. (2019). Scalable analysis for arbitrary photonic integrated waveguide meshes. Optica, 6(1), 19. doi:10.1364/optica.6.000019Rios, C., Stegmaier, M., Cheng, Z., Youngblood, N., Wright, C. D., Pernice, W. H. P., & Bhaskaran, H. (2018). Controlled switching of phase-change materials by evanescent-field coupling in integrated photonics [Invited]. Optical Materials Express, 8(9), 2455. doi:10.1364/ome.8.002455Zheng, J., Khanolkar, A., Xu, P., Colburn, S., Deshmukh, S., Myers, J., … Majumdar, A. (2018). GST-on-silicon hybrid nanophotonic integrated circuits: a non-volatile quasi-continuously reprogrammable platform. Optical Materials Express, 8(6), 1551. doi:10.1364/ome.8.001551Capmany, J., Domenech, D., & Muñoz, P. (2014). Silicon graphene waveguide tunable broadband microwave photonics phase shifter. Optics Express, 22(7), 8094. doi:10.1364/oe.22.008094Abel, S., Eltes, F., Ortmann, J. E., Messner, A., Castera, P., Wagner, T., … Fompeyrine, J. (2018). Large Pockels effect in micro- and nanostructured barium titanate integrated on silicon. Nature Materials, 18(1), 42-47. doi:10.1038/s41563-018-0208-0Sanchez, L., Lechago, S., Gutierrez, A., & Sanchis, P. (2016). Analysis and Design Optimization of a Hybrid VO2/Silicon2 $\times$ 2 Microring Switch. IEEE Photonics Journal, 8(2), 1-9. doi:10.1109/jphot.2016.2551463Qiao, L., Tang, W., & Chu, T. (2017). 32 × 32 silicon electro-optic switch with built-in monitors and balanced-status units. Scientific Reports, 7(1). doi:10.1038/srep42306Zheng, D., Doménech, J. D., Pan, W., Zou, X., Yan, L., & Pérez, D. (2019). Low-loss broadband 5  ×  5 non-blocking Si3N4 optical switch matrix. Optics Letters, 44(11), 2629. doi:10.1364/ol.44.002629Capmany, J., Gasulla, I., & Pérez, D. (2015). The programmable processor. Nature Photonics, 10(1), 6-8. doi:10.1038/nphoton.2015.254Carolan, J., Harrold, C., Sparrow, C., Martín-López, E., Russell, N. J., Silverstone, J. W., … Laing, A. (2015). Universal linear optics. Science, 349(6249), 711-716. doi:10.1126/science.aab3642Lee, B. G., & Dupuis, N. (2019). Silicon Photonic Switch Fabrics: Technology and Architecture. Journal of Lightwave Technology, 37(1), 6-20. doi:10.1109/jlt.2018.2876828Seok, T. J., Quack, N., Han, S., Muller, R. S., & Wu, M. C. (2016). Large-scale broadband digital silicon photonic switches with vertical adiabatic couplers. Optica, 3(1), 64. doi:10.1364/optica.3.00006

Comparisons of oncological and functional outcomes among radical retropubic prostatectomy, high dose rate brachytherapy, cryoablation and high-intensity focused ultrasound for localized prostate cancer: A prospective, controlled, nonrandomized trial

Background: Several clinical decision rules (CDRs) are available to exclude acute pulmonary embolism (PE), but they have not been directly compared. Objective: To directly compare the performance of 4 CDRs (Wells rule, revised Geneva score, simplified Wells rule, and simplified revised Geneva score) in combination with D-dimer testing to exclude PE. Design: Prospective cohort study. Setting: 7 hospitals in the Netherlands. Patients: 807 consecutive patients with suspected acute PE. Intervention: The clinical probability of PE was assessed by using a computer program that calculated all CDRs and indicated the next diagnostic step. Results of the CDRs and D-dimer tests guided clinical care. Measurements: Results of the CDRs were compared with the prevalence of PE identified by computed tomography or venous thromboembolism at 3-month follow-up. Results: Prevalence of PE was 23%. The proportion of patients categorized as PE-unlikely ranged from 62% (simplified Wells rule) to 72% (Wells rule). Combined with a normal D-dimer result, the CDRs excluded PE in 22% to 24% of patients. The total failure rates of the CDR and D-dimer combinations were similar (1 failure, 0.5% to 0.6% [upper-limit 95% CI, 2.9% to 3.1%]). Even though 30% of patients had discordant CDR outcomes, PE was not detected in any patient with discordant CDRs and a normal D-dimer result. Limitation: Management was based on a combination of decision rules and D-dimer testing rather than only 1 CDR combined with D-dimer testing. Conclusion: All 4 CDRs show similar performance for exclusion of acute PE in combination with a normal D-dimer result. This prospective validation indicates that the simplified scores may be used in clinical practice. Primary Funding Source: Academic Medical Center, VU University Medical Center, Rijnstate Hospital, Leiden University Medical Center, Maastricht University Medical Center, Erasmus Medical Center, and Maasstad Hospital. © 2011 American College of Physicians

Pandorae Sive Veniae Hispanicae Belgicis Exulibvs, M.D.LXXIIII. Mense Ivlio Editae : Item, Bvllae Greg. XIII. Sive Papalis veniae Anatomia ... Item, Iusivrandvm Poenitentivm cum Epilogo eiusdem autoris

Prometheo AvtoreKnuttel, W.P.C. Catalogus van de pamfletten-verzameling berustende in de Koninklijke Bibliotheek, 222Prometheus Pseud.Geurts, P.A.M. De Nederlandse Opstand in de pamfletten 1566-1584, S. 49: "commentaar op het pardon: ... Na een zeer felle inleiding, waarin ook de koning rechtstreeks en in uiterst scherpe bewoordingen wordt aangevallen, ontleedt het pamflet de in de titel genoemde stukken, die tot in details worden gecritiseerd... Het latijnse ‘Pardona wordt met een woordspeling ‘Pandora, de eerste vrouw, die met haar bedriegelijke gaven de oorzaak was van alle rampen ... Volgelingen van Epimetheus zijn de Nederlanders die op het pardon van Requesens ingaan. De auteur noemt zich Prometheus, omdat hij de nederlandse ballingen van die noodlottige stap probeert terug te houdenAan het eind gesigneerd: P.CVorlageform des Erscheinungsvermerks: 1574. Mense Novemb.Knuttel 222Belgica Typographica 4063Netherlandish Books 2603

Radiologic physics : war machine

383 p. : ill. ; 28 cm