High School Exit Examinations: When Do Learning Effects Generalize?

This paper reviews international and domestic evidence on the effects of three types of high school exit exam systems: voluntary curriculum-based external exit exams, universal curriculum-based external exit exam systems and minimum competency tests that must be passed to receive a regular high school diploma. The nations and provinces that use Universal CBEEES (and typically teacher grades as well) to signal student achievement have significantly higher achievement levels and smaller differentials by family background than otherwise comparable jurisdictions that base high stakes decisions on voluntary college admissions tests and/or teacher grades. The introduction of Universal CBEEES in New York and North Carolina during the 1990s was associated with large increases in math achievement on NAEP tests. Research on MCTs and high school accountability tests is less conclusive because these systems are new and have only been implemented in one country. Cross-section studies using a comprehensive set of controls for family background have not found that students in MCT states score higher on audit tests like the NAEP that carry no stakes for the test taker. The analysis reported in table 1 tells us that the five states that introduced MCTs during the 1990s had significantly larger improvements on NAEP tests than states that made no change in their student accountability regime. The gains, however, are smaller than for the states introducing Universal CBEEES. New York and North Carolina. The most positive finding about MCTs is that students in MCT states earn significantly more during the first eight years after graduation than comparable students in other states suggesting that MCTs improve employer perceptions of the quality of the recent graduates of local high schools

A comprehensive survey on quantum computer usage: How many qubits are employed for what purposes?

Quantum computers (QCs), which work based on the law of quantum mechanics, are expected to be faster than classical computers in several computational tasks such as prime factoring and simulation of quantum many-body systems. In the last decade, research and development of QCs have rapidly advanced. Now hundreds of physical qubits are at our disposal, and one can find several remarkable experiments actually outperforming the classical computer in a specific computational task. On the other hand, it is unclear what the typical usages of the QCs are. Here we conduct an extensive survey on the papers that are posted in the quant-ph section in arXiv and claim to have used QCs in their abstracts. To understand the current situation of the research and development of the QCs, we evaluated the descriptive statistics about the papers, including the number of qubits employed, QPU vendors, application domains and so on. Our survey shows that the annual number of publications is increasing, and the typical number of qubits employed is about six to ten, growing along with the increase in the quantum volume (QV). Most of the preprints are devoted to applications such as quantum machine learning, condensed matter physics, and quantum chemistry, while quantum error correction and quantum noise mitigation use more qubits than the other topics. These imply that the increase in QV is fundamentally relevant, and more experiments for quantum error correction, and noise mitigation using shallow circuits with more qubits will take place.Comment: 14 pages, 5 figures, figures regenerate

Search for astronomical neutrinos from blazar TXS 0506+056 in super-kamiokande

We report a search for astronomical neutrinos in the energy region from several GeV to TeV in the direction of the blazar TXS 0506+056 using the Super-Kamiokande detector following the detection of a 100 TeV neutrinos from the same location by the IceCube collaboration. Using Super-Kamiokande neutrino data across several data samples observed from 1996 April to 2018 February we have searched for both a total excess above known backgrounds across the entire period as well as localized excesses on smaller timescales in that interval. No significant excess nor significant variation in the observed event rate are found in the blazar direction. Upper limits are placed on the electron- and muon-neutrino fluxes at the 90% confidence level as 6.0 × 10−7 and 4.5 × 10−7–9.3 × 10−10 [erg cm−2 s−1], respectively

GMC Collisions as Triggers of Star Formation. III. Density and Magnetically Regulated Star Formation

We study giant molecular cloud (GMC) collisions and their ability to trigger star cluster formation. We further develop our three dimensional magnetized, turbulent, colliding GMC simulations by implementing star formation sub-grid models. Two such models are explored: (1) Density-Regulated, i.e., fixed efficiency per free-fall time above a set density threshold; (2) Magnetically- Regulated, i.e., fixed efficiency per free-fall time in regions that are magnetically supercritical. Variations of parameters associated with these models are also explored. In the non-colliding simulations, the overall level of star formation is sensitive to model parameter choices that relate to effective density thresholds. In the GMC collision simulations, the final star formation rates and efficiencies are relatively independent of these parameters. Between non-colliding and colliding cases, we compare the morphologies of the resulting star clusters, properties of star-forming gas, time evolution of the star formation rate (SFR), spatial clustering of the stars, and resulting kinematics of the stars in comparison to the natal gas. We find that typical collisions, by creating larger amounts of dense gas, trigger earlier and enhanced star formation, resulting in 10 times higher SFRs and efficiencies. The star clusters formed from GMC collisions show greater spatial sub-structure and more disturbed kinematics

GMC Collisions as Triggers of Star Formation. II. 3D Turbulent, Magnetized Simulations

We investigate giant molecular cloud (GMCs) collisions and their ability to induce gravitational instability and thus star formation. This mechanism may be a major driver of star formation activity in galactic disks. We carry out a series of three dimensional, magnetohydrodynamics (MHD), adaptive mesh refinement (AMR) simulations to study how cloud collisions trigger formation of dense filaments and clumps. Heating and cooling functions are implemented based on photo-dissociation region (PDR) models that span the atomic to molecular transition and can return detailed diagnostic information. The clouds are initialized with supersonic turbulence and a range of magnetic field strengths and orientations. Collisions at various velocities and impact parameters are investigated. Comparing and contrasting colliding and non-colliding cases, we characterize morphologies of dense gas, magnetic field structure, cloud kinematic signatures, and cloud dynamics. We present key observational diagnostics of cloud collisions, especially: relative orientations between magnetic fields and density structures, like filaments; 13CO(J=2-1), 13CO(J=3-2), and 12CO(J=8-7) integrated intensity maps and spectra; and cloud virial parameters. We compare these results to observed Galactic clouds

Search for proton decay into three charged leptons in 0.37 megaton-years exposure of the Super-Kamiokande

A search for proton decay into three charged leptons has been performed by using 0.37 Mton⋅years of data collected in Super-Kamiokande. All possible combinations of electrons, muons, and their antiparticles consistent with charge conservation were considered as decay modes. No significant excess of events has been found over the background, and lower limits on the proton lifetime divided by the branching ratio have been obtained. The limits range between 9.2×10^33 and 3.4×10^34 years at 90% confidence level, improving by more than an order of magnitude upon limits from previous experiments. A first limit has been set for the p→μ^−e^+e^+ mode

Search for astronomical neutrinos from blazar TXS 0506+056 in Super-Kamiokande

We report a search for astronomical neutrinos in the energy region from several GeV to TeV in the direction of the blazar TXS 0506+056 using the Super-Kamiokande detector following the detection of a 100 TeV neutrinos from the same location by the IceCube collaboration. Using Super-Kamiokande neutrino data across several data samples observed from 1996 April to 2018 February we have searched for both a total excess above known backgrounds across the entire period as well as localized excesses on smaller timescales in that interval. No significant excess nor significant variation in the observed event rate are found in the blazar direction. Upper limits are placed on the electron- and muon-neutrino fluxes at the 90% confidence level as 6.0 × 10−7 and 4.5 × 10−7–9.3 × 10−10 [erg cm−2 s−1], respectively