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In analogy to cavity optomechanics, enhancing specific sidebands of a Raman process with narrowband optical resonators would allow for parametric amplification, entanglement of light and molecular vibrations, and reduced transduction noise. We report on the demonstration of waveguide-addressable sideband-resolved surface-enhanced Raman scattering (SERS). We realized a hybrid plasmonic-photonic resonator consisting of a 1D photonic crystal cavity decorated with a sub-20 nm gap dimer nanoantenna. Hybrid resonances in the near-IR provide designer Q-factors of 1000, and $Q/V=(\lambda^3/10^6)^{-1}$, with SERS signal strength on par with levels found in state-of-the-art purely plasmonic systems. We evidence Fano-lineshapes in the SERS enhancement of organic molecules, and quantitatively separate out the pump enhancement and optical reservoir contributions., Comment: Main text: 6 pages, Supplementary information: 12 pages

Hot subdwarf stars are mostly stripped red giants that can exhibit photometric variations due to stellar pulsations, eclipses, the reflection effect, ellipsoidal modulation, and Doppler beaming. Detailed studies of their light curves help constrain stellar parameters through asteroseismological analyses or binary light curve modeling and generally improve our capacity to draw a statistically meaningful picture of this enigmatic stage of stellar evolution. From an analysis of Gaia DR2 flux errors, we have identified around 1200 candidate hot subdwarfs with inflated flux errors for their magnitudes - a strong indicator of photometric variability. As a pilot study, we obtained 2-min cadence TESS Cycle 2 observations of 187 candidate hot subdwarfs with anomalous Gaia flux errors. More than 90% of our targets show significant photometric variations in their TESS light curves. Many of the new systems found are cataclysmic variables, but we report the discovery of several new variable hot subdwarfs, including HW Vir binaries, reflection effect systems, pulsating sdBVs stars, and ellipsoidally modulated systems. We determine atmospheric parameters for select systems using follow-up spectroscopy from the 3-m Shane telescope. Finally, we present a Fourier diagnostic plot for classifying binary light curves using the relative amplitudes and phases of their fundamental and harmonic signals in their periodograms. This plot makes it possible to identify certain types of variables efficiently, without directly investigating their light curves, and may assist in the rapid classification of systems observed in large photometric surveys., Comment: 24 pages, 18 figures, 5 tables; accepted for publication in ApJ

We report on a Python-toolbox for unbiased statistical analysis of fluorescence intermittency properties of single emitters. Intermittency, i.e., step-wise temporal variations in the instantaneous emission intensity and fluorescence decay rate properties are common to organic fluorophores, II-VI quantum dots and perovskite quantum dots alike. Unbiased statistical analysis of intermittency switching time distributions, involved levels and lifetimes is important to avoid interpretation artefacts. This work provides an implementation of Bayesian changepoint analysis and level clustering applicable to time-tagged single-photon detection data of single emitters that can be applied to real experimental data and as tool to verify the ramifications of hypothesized mechanistic intermittency models. We provide a detailed Monte Carlo analysis to illustrate these statistics tools, and to benchmark the extent to which conclusions can be drawn on the photophysics of highly complex systems, such as perovskite quantum dots that switch between a plethora of states instead of just two., Comment: Corresponds to Python code at https://github.com/AMOLFResonantNanophotonics/CPA Updated version (Feb 25) contains ZENODO link to code and data, and arxiv identifiers to related work

We analyze intermittency in intensity and fluorescence lifetime of CsPbBr$_3$ perovskite quantum dots by applying unbiased Bayesian inference analysis methods. We apply changepoint analysis (CPA) and a Bayesian state clustering algorithm to determine the timing of switching events and the number of states between which switching occurs in a statistically unbiased manner, which we have benchmarked particularly to apply to highly multistate emitters. We conclude that perovskite quantum dots display a plethora of gray states in which brightness broadly speaking correlates inversely with decay rate, confirming the multiple recombination centers model. We leverage the CPA partitioning analysis to examine aging and memory effects. We find that dots tend to return to the bright state before jumping to a dim state, and that when choosing a dim state they tend to explore the entire set of states available., Comment: Preprint itself 32 pages double spaced with 7 figures. Remainder is supplementary data plots for 40 single quantum dots First update: inserted ZENODO data link, and arxiv identifier for related reference

Modulated electron radiotherapy (MERT) and combined, modulated photon/electron radiotherapy (MPERT) have received increased research attention, having shown capacity for reduced low dose exposure to healthy tissue and comparable, if not improved, target coverage for a number of treatment sites. Accurate dose calculation tools are necessary for clinical treatment planning, and Monte Carlo (MC) is the gold standard for electron field simulation. With many clinics replacing older accelerators, MC source models of the new machines are needed for continued development, however, Varian has kept internal schematics of the TrueBeam confidential and electron phase-space sources have not been made available. TrueBeam electron fields are not substantially different from those generated by the Clinac 21EX, so we have modified the internal schematics of the Clinac 21EX to simulate TrueBeam electrons. BEAMnrc/DOSXYZnrc were used to simulate 5x5 and 20x20 cm$^2$ electron fields with MLC-shaped apertures. Secondary collimating jaws were set 0.5 cm beyond the MLC periphery and to 40x40 cm$^2$. Complete accelerator models agreed with diode measurement within 2%/2 mm at 12 and 20 MeV, and within 3%/3 mm at 6 MeV. Comparisons of measured depth and profile data showed dose-dependencies on jaw position; simulated energy fluences scored just above the phantom showed that, for small apertures, dose dependencies on jaw position are dominated by changes in the in-field energy fluence (not scattered by jaws or MLC) at 6 MeV, while at 20 MeV dose dependencies are dominated by the scattered component. Our models reproduce these jaw position dependencies, which is an asset as there is no consensus on the optimal position for jaws in modulated electron field delivery. Good agreement between simulation and measurement and flexibility in jaw position make our models appropriate for use in MERT and MPERT planning., Comment: 18 pages, 5 figures, 4 tables; v2 - corrected typo on page 17 and in references

Kernel ridge regression is used to approximate the kinetic energy of non-interacting fermions in a one-dimensional box as a functional of their density. The properties of different kernels and methods of cross-validation are explored, and highly accurate energies are achieved. Accurate {\em constrained optimal densities} are found via a modified Euler-Lagrange constrained minimization of the total energy. A projected gradient descent algorithm is derived using local principal component analysis. Additionally, a sparse grid representation of the density can be used without degrading the performance of the methods. The implications for machine-learned density functional approximations are discussed.

Twitter is a micro-blogging social media platform for short messages that can have a long-term impact on how scientists create and publish ideas. We investigate the usefulness of twitter in the development and distribution of scientific knowledge. At the start of the life cycle of a scientific publication, twitter provides a large virtual department of colleagues that can help to rapidly generate, share and refine new ideas. As ideas become manuscripts, twitter can be used as an informal arena for the pre-review of works in progress. Finally, tweeting published findings can communicate research to a broad audience of other researchers, decision makers, journalists and the general public that can amplify the scientific and social impact of publications. However, there are limitations, largely surrounding issues of intellectual property and ownership, inclusiveness and misrepresentations of science sound bites. Nevertheless, we believe twitter is a useful social media tool that can provide a valuable contribution to scientific publishing in the 21st century., Comment: 31 pages, 5 figures

The Saskatoon Region Shared Service was formed by one urban and three adjoining rural school divisions in Saskatchewan (Canada), to serve a small, widespread population base of special needs students. The Shared Service established the Behavior Adjustment Model to develop a continuum of services for children with social and emotional problems. The program provides videotapes on classroom management for inservice teacher education and offers support services from a behavior consultant, social worker, psychologist, school administrator, or resource teacher. The procedures for receiving these support services are described. Statistical data on the numbers of clients served and types of services are provided. The Shared Service also developed the Social Learning Centre, to meet the needs of students with severe behavioral problems who are unable to cope with, or benefit from, the regular classroom program. The document describes the Centre's service approach, student population, staff, program individualization, length of stay, student integration and reintegration, funding, and volunteer involvement. (JDD)