Neutron monitors and muon detectors for solar modulation studies: Interstellar flux, yield function, and assessment of critical parameters in count rate calculations

Particles count rates at given Earth location and altitude result from the convolution of (i) the interstellar (IS) cosmic-ray fluxes outside the solar cavity, (ii) the time-dependent modulation of IS into Top-of-Atmosphere (TOA) fluxes, (iii) the rigidity cut-off (or geomagnetic transmission function) and grammage at the counter location, (iv) the atmosphere response to incoming TOA cosmic rays (shower development), and (v) the counter response to the various particles/energies in the shower. Count rates from neutron monitors or muon counters are therefore a proxy to solar activity. In this paper, we review all ingredients, discuss how their uncertainties impact count rate calculations, and how they translate into variation/uncertainties on the level of solar modulation $\varphi$ (in the simple Force-Field approximation). The main uncertainty for neutron monitors is related to the yield function. However, many other effects have a significant impact, at the 5-10\% level on $\varphi$ values. We find no clear ranking of the dominant effects, as some depend on the station position and/or the weather and/or the season. An abacus to translate any variation of count rates (for neutron and $\mu$ detectors) to a variation of the solar modulation $\varphi$ is provided.Comment: 28 pages, 16 figures, 9 tables, match accepted version in AdSR (minor corrections, Dorman (1974,2004,2009) reference textbooks added

Neutron monitors and muon detectors for solar modulation studies: 2. ϕ\phi time series

The level of solar modulation at different times (related to the solar activity) is a central question of solar and galactic cosmic-ray physics. In the first paper of this series, we have established a correspondence between the uncertainties on ground-based detectors count rates and the parameter $\phi$ (modulation level in the force-field approximation) reconstructed from these count rates. In this second paper, we detail a procedure to obtain a reference $\phi$ time series from neutron monitor data. We show that we can have an unbiased and accurate $\phi$ reconstruction ($\Delta\phi/\phi\simeq 10\%$). We also discuss the potential of Bonner spheres spectrometers and muon detectors to provide $\phi$ time series. Two by-products of this calculation are updated $\phi$ values for the cosmic-ray database and a web interface to retrieve and plot $\phi$ from the 50's to today (\url{http://lpsc.in2p3.fr/crdb}).Comment: 15 pages, 5 figures, 2 tables. AdSR, in press. Web interface to get modulation parameter phi(t): new tab in http://lpsc.in2p3.fr/crd

2/3D imaging based on photonics-enabled multi-band MIMO radar system

Photonics-enabled coherent MIMO radars have been numerically investigated to evaluate the benefits of coherence and multi-band operation in 2/3D imaging

Effect of cattle trampling and farm machinery traffic on soil compaction of an Entic Haplustoll in a semiarid region of Argentina

Soil compaction has detrimental effects on the physical, mechanical and hydraulic properties of soils, and affects important soil processes and function, and crop productivity. This work was conducted to investigate soil compaction impacts in integrated arable croppinglivestock systems managed under conventional tillage (CT) and no-tillage (NT). The work examined the combined effects of cattle trampling and farm machinery traffic on: soil strength, soil deformation, and water infiltration into soil. The following treatments were applied to soil (Entic Haplustoll, 60% sand) managed under CT and NT: three traffic intensities (1, 5, 7 passes) performed with light (2WD, 53 kN) and heavy (4WD, 100.4 kN) tractors, and two stocking densities (400 and 700 kg ha-1 ), respectively. Controls were also used to represent the condition of the soil without any effect of livestock or field traffic. In both tillage systems, soil penetration resistance (strength) increased and water infiltration into soil decreased as traffic intensities or stocking rates applied increased. There was a significant traffic intensity × stocking rate interaction, which influenced the depth and extent of soil compaction at depth. Despite these results, stubble grazing during fallow should not be discouraged as this practice offers mixed farming systems several agronomic and financial benefits. If stubble was to be grazed, the system would need to be carefully managed: (1) avoid ‘random’ traffic using permanent or semipermanent traffic paths to minimise the field wheeled area, (2) vacate livestock from the field, or confine it to a sacrificial area, when the soil water content exceeds a critical level above which soil damage is likely, and (3) maintain more than 60%–70% ground cover. Tillage repair treatments can be targeted to those sacrificial or ‘hot-spots’ areas so that localised, as supposed to widespread, compaction problems are rectified before the next crop is established

Design and Performance Estimation of a Photonic Integrated Beamforming Receiver for Scan-On-Receive Synthetic Aperture Radar

Synthetic aperture radar is a remote sensing technology finding applications in a wide range of fields, especially related to Earth observation. It enables a fine imaging that is crucial in critical activities, like environmental monitoring for natural resource management or disasters prevention. In this picture, the scan-on-receive paradigm allows for enhanced imaging capabilities thanks to wide swath observations at finer azimuthal resolution achieved by beamforming of multiple simultaneous antenna beams. Recently, solutions based on microwave photonics techniques demonstrated the possibility of an efficient implementation of beamforming, overcoming some limitations posed by purely electronic solutions, offering unprecedented flexibility and precision to RF systems. Moreover, photonics-assisted RF beamformers can nowadays be realized as integrated circuits, with reduced size and power consumption with respect to digital beamforming approaches. This paper presents the design analysis and the challenges of the development of a hybrid photonic-integrated circuit as the core element of an X-band scan-on-receive spaceborne synthetic aperture radar. The proposed photonic-integrated circuit synthetizes three simultaneous scanning beams on the received signal, and performs the frequency down-conversion, guaranteeing a compact 15 cm2-form factor, less than 6 W power consumption, and 55 dB of dynamic range. The whole photonics-assisted system is designed for space compliance and meets the target application requirements, representing a step forward toward a deeper penetration of photonics in microwave applications for challenging scenarios, like the observation of the Earth from space

Multipurpose silicon photonics signal processor core

[EN] Integrated photonics changes the scaling laws of information and communication systems offering architectural choices that combine photonics with electronics to optimize performance, power, footprint, and cost. Application-specific photonic integrated circuits, where particular circuits/chips are designed to optimally perform particular functionalities, require a considerable number of design and fabrication iterations leading to long development times. A different approach inspired by electronic Field Programmable Gate Arrays is the programmable photonic processor, where a common hardware implemented by a two-dimensional photonic waveguide mesh realizes different functionalities through programming. Here, we report the demonstration of such reconfigurable waveguide mesh in silicon. We demonstrate over 20 different functionalities with a simple seven hexagonal cell structure, which can be applied to different fields including communications, chemical and biomedical sensing, signal processing, multiprocessor networks, and quantum information systems. Our work is an important step toward this paradigm.J.C. acknowledges funding from the ERC Advanced Grant ERC-ADG-2016-741415 UMWP-Chip, I.G. acknowledges the funding through the Spanish MINECO Ramon y Cajal program. D.P. acknowledges financial support from the UPV through the FPI predoctoral funding scheme. D.J.T. acknowledges funding from the Royal Society for his University Research Fellowship.Pérez-López, D.; Gasulla Mestre, I.; Crudgington, L.; Thomson, DJ.; Khokhar, AZ.; Li, K.; Cao, W.... (2017). Multipurpose silicon photonics signal processor core. Nature Communications. 8(1925):1-9. https://doi.org/10.1038/s41467-017-00714-1S1981925Doerr, C. R. & Okamoto, K. Advances in silica planar lightwave circuits. J. Lightw. Technol. 24, 4763–4789 (2006).Coldren, L. A. et al. High performance InP-based photonic ICs—A tutorial. J. Lightw. Technol 29, 554–570 (2011).Soref, R. The past, present, and future of silicon photonics. IEEE J. Sel. Top. Quantum Electron. 12, 1678–1687 (2006).Bogaerts, W. Design challenges in silicon photonics. IEEE J. Sel. Top. Quantum Electron. 20, 8202008 (2014).Bogaerts, W. et al. Nanophotonic waveguides in silicon-on-insulator fabricated with CMOS technology. J. Lightw. Technol. 23, 401–412 (2005).Smit, M. K. et al. An introduction to InP-based generic integration technology. Semicond. Sci. Technol. 29, 083001 (2014).Leinse, A. et al. TriPleX waveguide platform: low-loss technology over a wide wavelength range. Proc. SPIE 8767, 87670E (2013).Kish, F. et al. From visible light-emitting diodes to large-scale III–V photonic integrated circuits. Proc. IEEE 101, 2255–2270 (2013).Heck, M. J. R. et al. Hybrid silicon photonic integrated circuit technology. IEEE J. Sel. Top. Quantum Electron. 19, 6100117 (2013).Sacher, W. et al. Multilayer silicon nitride-on-silicon integrated photonic platforms and devices. J. Lightw. Technol. 33, 901–910 (2015).Asghari, M. Silicon photonics: A low cost integration platform for datacom and telecom applications. In OFC/NFOEC 2008 – 2008 Conference on Optical Fiber Communication/National Fiber Optic Engineers Conference 1–10 (San Diego, USA, 2008).Melati, D. et al. Integrated all-optical MIMO demultiplexer for mode- and wavelength-division-multiplexed transmission. Opt. Lett. 42, 342–345 (2017).Waterhouse, R. & Novak, D. Realizing 5G: microwave photonics for 5G mobile wireless systems. IEEE Microw. Mag. 16, 84–92 (2015).Marpaung, D. et al. Integrated microwave photonics. Laser Photon. Rev. 7, 506–538 (2013).Iezekiel, S., Burla, M., Klamkin, J., Marpaung, D. & Capmany, J. RF engineering meets optoelectronics: Progress in integrated microwave photonics. IEEE Microw. Mag. 16, 28–45 (2015).Technology focus on microwave photonics. Nat. Photon. 5, 723 (2011).Ghelfi, P. et al. A fully photonics-based coherent radar system. Nature 507, 341–345 (2014).Heideman, R. G. TriPleX™-based integrated optical ring resonators for lab-ona-chip-and environmental detection. IEEE J. Sel. Top. Quantum Electron. 18, 1583–1596 (2012).Estevez, M. C., Alvarez, M. & Lechuga, L. Integrated optical devices for lab-on-a-chip biosensing applications. Laser Photon. Rev. 6, 463–487 (2012).Almeida, V. R., Barrios, C. A., Panepucci, R. & Lipson, M. All-optical control of light on a silicon chip. Nature 431, 1081–1084 (2004).Norberg, E. J., Guzzon, R. S., Parker, J. S., Johansson, L. A. & Coldren, L. A. Programmable photonic microwave filters monolithically integrated in InP/InGaAsP. J. Lightw. Technol. 29, 1611–1619 (2011).Wang, J. et al. Reconfigurable radio-frequency arbitrary waveforms synthesized in a silicon photonic chip. Nat. Commun. 6, 5957 (2015).Hill, M. T. et al. A fast low power optical memory based on coupled micro-ring lasers. Nature 432, 206–209 (2004).Slavík, R. et al. Photonic temporal integrator for all-optical computing. Opt. Express 16, 18202–18214 (2008).Sun, C. et al. A monolithically-integrated chip-to-chip optical link in bulk CMOS. IEEE J. Solid-State Circ. 50, 828–844 (2015).Sun, C. et al. Single-chip microprocessor that communicates directly using light. Nature 528, 534–538 (2015).Assefa, S. et al. in Optical Fibre Communication Conference OMM6, https://www.osapublishing.org/abstract.cfm?uri=OFC-2011-OMM6 (Optical Society of America, 2011).Peruzzo, A. et al. Multimode quantum interference of photons in multiport integrated devices. Nat. Commun. 2, 224 (2011).Bonneau, D. et al. Quantum interference and manipulation of entanglement in silicon wire waveguide quantum circuits. N. J. Phys. 14, 045003 (2012).Metcalf, B. J. et al. Multiphoton quantum interference in a multiport integrated photonic device. Nat. Commun. 4, 1356 (2013).Muñoz, P. et al. in 16th International Conference on Transparent Optical Networks (ICTON), 1–4 (Graz, 2014).Ribeiro, A. et al. Demonstration of a 4×4-port universal linear circuit. Optica 3, 1348–1357 (2016).Liu, W. et al. A fully reconfigurable photonic integrated signal processor. Nat. Photon 10, 190–195 (2016).Graydon, O. Birth of the programmable optical chip. Nat. Photon 10, 1 (2016).Pérez, D., Gasulla, I. & Capmany, J. Software-defined reconfigurable microwave photonics processor. Opt. Express 23, 14640–14654 (2015).Miller, D. A. B. Self-configuring universal linear optical component. Photon. Res. 1, 1–15 (2013).Miller, D. A. B. Self-aligning universal beam coupler. Opt. Express 21, 6360–6370 (2013).Clements, W. R. et al. Optimal design for universal multiport interferometers. Optica 3, 1460–1465 (2016).Zhuang, L., Roeloffzen, C. G. H., Hoekman, M., Boller, K.-J. & Lowery, A. J. Programmable photonic signal processor chip for radiofrequency applications. Optica 2, 854–859 (2015).Capmany, J., Gasulla, I. & Pérez, D. Microwave photonics: The programmable processor. Nat. Photon. 10, 6–8 (2016).Pérez, D., Gasulla., Capmany, J. & Soref, R. A. Reconfigurable lattice mesh designs for programmable photonic processors. Opt. Express 24, 12093–12106 (2016).Madsen, C. K. & Zhao, J. H. Optical Filter Design and Analysis: A Signal Processing Approach. 1st edn. (Wiley, 1999).Jinguji, K. Synthesis of coherent two-port lattice-form optical delay-line circuit. J. Lightw. Technol. 13, 73–82 (1995).Jinguji, K. Synthesis of coherent two-port Optical delay-line circuit with ring waveguides. J. Lightw. Technol. 14, 1882–1898 (1996).Madsen, C. K. General IIR optical filter design for WDM applications using all-pass filters. J. Lightw. Technol. 18, 860–868 (2000).Burla, M. et al. On-chip CMOS compatible reconfigurable optical delay line with separate carrier tuning for microwave photonic signal processing. Opt. Express 19, 21475–21484 (2011).Yariv, A. et al. Coupled resonator optical waveguides: a proposal and analysis. Opt. Lett. 24, 711–713 (1999).Hebner, J. E. et al. Distributed and localized feedback in microresonator sequences for linear and nonlinear optics. J. Opt. Soc. Am. B. 21, 1665–1673 (2004).Fandiño, J. S. et al. A monolithic integrated photonic microwave filter. Nat. Photon. 11, 124–129 (2017).Miller, D. A. B. All linear optical devices are mode converters. Opt. Express 20, 23985–23993 (2012).Reck, M. et al. Experimental realization of any discrete unitary operator. Phys. Rev. Lett. 73, 58–61 (1994).Carolan, J. et al. Universal linear optics. Science 349, 711 (2015).Nielsen, M. A. & Chuang, I. L. Quantum Computation and Quantum Information. 1st edn. (Cambridge University Press, 2001).Miller, D. A. B. Perfect optics with imperfect components. Optica 2, 747–750 (2015).Grillanda, S. et al. Non-invasive monitoring and control in silicon photonics using CMOS integrated electronics. Optica 1, 129–136 (2014)

Acute effects of fine particulate air pollution on ST segment height: A longitudinal study

Background The mechanisms for the relationship between particulate air pollution and cardiac disease are not fully understood. Air pollution-induced myocardial ischemia is one of the potentially important mechanisms. Methods We investigate the acute effects and the time course of fine particulate pollution (PM2.5) on myocardium ischemic injury as assessed by ST-segment height in a community-based sample of 106 healthy non-smokers. Twenty-four hour beat-to-beat electrocardiogram (ECG) data were obtained using a high resolution 12-lead Holter ECG system. After visually identifying and removing all the artifacts and arrhythmic beats, we calculated beat-to-beat ST-height from ten leads (inferior leads II, III, and aVF; anterior leads V3 and V4; septal leads V1 and V2; lateral leads I, V5, and V6,). Individual-level 24-hour real-time PM2.5 concentration was obtained by a continuous personal PM2.5 monitor. We then calculated, on a 30-minute basis, the corresponding time-of-the-day specific average exposure to PM2.5 for each participant. Distributed lag models under a linear mixed-effects models framework were used to assess the regression coefficients between 30-minute PM2.5 and ST-height measures from each lead; i.e., one lag indicates a 30-minute separation between the exposure and outcome. Results The mean (SD) age was 56 (7.6) years, with 41% male and 74% white. The mean (SD) PM2.5 exposure was 14 (22) μg/m3. All inferior leads (II, III, and aVF) and two out of three lateral leads (I and V6), showed a significant association between higher PM2.5 levels and higher ST-height. Most of the adverse effects occurred within two hours after PM2.5 exposure. The multivariable adjusted regression coefficients β (95% CI) of the cumulative effect due to a 10 μg/m3 increase in Lag 0-4 PM2.5 on ST-I, II, III, aVF and ST-V6 were 0.29 (0.01-0.56) μV, 0.79 (0.20-1.39) μV, 0.52 (0.01-1.05) μV, 0.65 (0.11-1.19) μV, and 0.58 (0.07-1.09) μV, respectively, with all p < 0.05. Conclusions Increased PM2.5 concentration is associated with immediate increase in ST-segment height in inferior and lateral leads, generally within two hours. Such an acute effect of PM2.5 may contribute to increased potential for regional myocardial ischemic injury among healthy individuals

Reexamining the effect of gustatory disgust on moral judgment: A multi-lab direct replication of Eskine, Kacinik, and Prinz (2011)

Tufts University Faculty Research Awar

Precision Measurement of the Boron to Carbon Flux Ratio in Cosmic Rays from 1.9 GV to 2.6 TV with the Alpha Magnetic Spectrometer on the International Space Station

Knowledge of the rigidity dependence of the boron to carbon flux ratio (B/C) is important in understanding the propagation of cosmic rays. The precise measurement of the B/C ratio from 1.9 GV to 2.6 TV, based on 2.3 million boron and 8.3 million carbon nuclei collected by AMS during the first 5 years of operation, is presented. The detailed variation with rigidity of the B/C spectral index is reported for the first time. The B/C ratio does not show any significant structures in contrast to many cosmic ray models that require such structures at high rigidities. Remarkably, above 65 GV, the B/C ratio is well described by a single power law R[superscript Δ] with index Δ=-0.333±0.014(fit)±0.005(syst), in good agreement with the Kolmogorov theory of turbulence which predicts Δ=-1/3 asymptotically.National Science Foundation (U.S.) (Grants 1455202 and 1551980)Wyle Research (Firm) (Grant 2014/T72497)United States. National Aeronautics and Space Administration (NASA Earth and Space Science Fellowship Grant HELIO15F-0005