The Spectroscopy of Nuclear Gamma-Rays

Abstract Not Provided

On the magnetospheric ULF wave counterpart of substorm onset

One near‐ubiquitous signature of substorms observed on the ground is the azimuthal structuring of the onset auroral arc in the minutes prior to onset. Termed auroral beads, these optical signatures correspond to concurrent exponential increases in ground ultralow frequency (ULF) wave power and are likely the result of a plasma instability in the magnetosphere. Here, we present a case study showing the development of auroral beads from a Time History of Events and Macroscale Interactions during Substorms (THEMIS) all‐sky camera with near simultaneous exponential increases in auroral brightness, ionospheric and conjugate magnetotail ULF wave power, evidencing their intrinsic link. We further present a survey of magnetic field fluctuations in the magnetotail around substorm onset. We find remarkably similar superposed epoch analyses of ULF power around substorm onset from space and conjugate ionospheric observations. Examining periods of exponential wave growth, we find the ground‐ and space‐based observations to be consistent, with average growth rates of ∼0.01 s−1, lasting for ∼4 min. Cross‐correlation suggests that the space‐based observations lead those on the ground by approximately 1–1.5 min. Meanwhile, spacecraft located premidnight and ∼10 RE downtail are more likely to observe enhanced wave power. These combined observations lead us to conclude that there is a magnetospheric counterpart of auroral beads and exponentially increasing ground ULF wave power. This is likely the result of the linear phase of a magnetospheric instability, active in the magnetotail for several minutes prior to auroral breakup

From safety net to trampoline:elevating learning with growth mindset in healthcare simulation

The Implicit Theory of Mindset proposes two different mindsets that sit at opposite ends of a spectrum: a fixed mindset versus a growth mindset. With a fixed mindset, an individual believes they are born with a certain amount of an attribute, and so their potential is both pre-determined and static. With a growth mindset, an individual believes their attributes are malleable and can strengthen over time with repeated effort, adaptable learning strategies, and challenge seeking. Adoption of a growth mindset is associated with improved academic success, more effective learning strategies, increased resilience in the face of adversity, and better mental wellbeing. The theoretical underpinning of psychological safety resonates with the Implicit Theory of Mindset as it infers that a significant number of simulation participants have a fixed mindset and are therefore more likely to be fearful of making an error. The simulation community agree that participants need to feel comfortable making errors for simulation to be successful. The key word here is comfortable. Participants feeling comfortable to make errors just scratches the surface of adopting a growth mindset. With a growth mindset, participants see errors as a positive in the simulation experience, an inevitability of the learning process, evidence that they are adequately challenging themselves to improve. Encouraging adoption of a growth mindset in participants is a powerful addition to the establishment of psychological safety because a growth mindset will re-frame participants’ experiences of social comparison from negative to positive and optimize information processing. We propose a novel idea: simulation educators should be explicit in the pre-brief about what a growth mindset is and its associated benefits to encourage its adoption during the simulation activity—a simulation growth mindset intervention. If this is not possible due to time constraints, an online module or article about growth mindset would be appropriate as pre-reading to encourage adoption of a growth mindset in participants. The message is not that a simulation growth mindset intervention should replace the focus on psychological safety but rather that it should be used synergistically to provide the highest quality simulation experience.</p

COBE ground segment gyro calibration

Discussed here is the calibration of the scale factors and rate biases for the Cosmic Background Explorer (COBE) spacecraft gyroscopes, with the emphasis on the adaptation for COBE of an algorithm previously developed for the Solar Maximum Mission. Detailed choice of parameters, convergence, verification, and use of the algorithm in an environment where the reference attitudes are determined form the Sun, Earth, and star observations (via the Diffuse Infrared Background Experiment (DIRBE) are considered. Results of some recent experiments are given. These include tests where the gyro rate data are corrected for the effect of the gyro baseplate temperature on the spacecraft electronics

Auditing the Election Ecosystem

Election administration is a highly complex process that involves multiple actors all working to achieve the goal of running an effective election. One critical technique for gathering the performance data needed to improve election management is through comprehensive evaluations, which we refer to as election ecosystem audits (EEA). These audits are evaluations of an election from start to finish. Accomplishing this goal requires election officials coordinating the efforts of contractors—from ballot printers to voting machine companies—third parties, like the US Postal Service who transport absentee ballots and the entities who agree to house polling places, and the poll workers who actually implement the election at the polls. Managing this vast enterprise requires election officials to evaluate their election activities so that they can improve the implementation of the process over time

Statistics of Solar Wind Electron Breakpoint Energies Using Machine Learning Techniques

Solar wind electron velocity distributions at 1 au consist of a thermal "core" population and two suprathermal populations: "halo" and "strahl". The core and halo are quasi-isotropic, whereas the strahl typically travels radially outwards along the parallel and/or anti-parallel direction with respect to the interplanetary magnetic field. With Cluster-PEACE data, we analyse energy and pitch angle distributions and use machine learning techniques to provide robust classifications of these solar wind populations. Initially, we use unsupervised algorithms to classify halo and strahl differential energy flux distributions to allow us to calculate relative number densities, which are of the same order as previous results. Subsequently, we apply unsupervised algorithms to phase space density distributions over ten years to study the variation of halo and strahl breakpoint energies with solar wind parameters. In our statistical study, we find both halo and strahl suprathermal breakpoint energies display a significant increase with core temperature, with the halo exhibiting a more positive correlation than the strahl. We conclude low energy strahl electrons are scattering into the core at perpendicular pitch angles. This increases the number of Coulomb collisions and extends the perpendicular core population to higher energies, resulting in a larger difference between halo and strahl breakpoint energies at higher core temperatures. Statistically, the locations of both suprathermal breakpoint energies decrease with increasing solar wind speed. In the case of halo breakpoint energy, we observe two distinct profiles above and below 500 km/s. We relate this to the difference in origin of fast and slow solar wind.Comment: Published in Astronomy & Astrophysics, 11 pages, 10 figure

Who Asks For Voter Identification? Explaining Poll-Worker Discretion

As street-level bureaucrats, poll workers bear the primary responsibility for implementing voter identification requirements. Voter identification requirements are not implemented equally across groups of voters, and poll workers exercise substantial discretion in how they apply election law. In states with minimal and varying identification requirements, poll workers appear to treat especially minority voters differently, requesting more stringent voter identification. We explain why poll workers are different from other street-level bureaucrats and how traditional mechanisms of control have little impact on limiting poll-worker discretion. We test why many poll workers appear not to follow the law using a post-election survey of New Mexico poll workers. We find little evidence that race, training, or partisanship matters. Instead, poll worker attitudes toward photo-identification policies and their educational attainment influences implementation of voter-identification laws

The Balance Between Preventing Fraud and Ensuring Participation: Attitudes Towards Voter Identification in New Mexico

This paper examines public opinion on the effectiveness and consequences of voter identification laws in New Mexico. In particular, it focuses on the attitudes central to the court reasoning in the 2008 Supreme Court case which upheld an Indiana photo-ID law, Crawford v. Marion County Election Board. Questions include whether or not voters think the ID laws protect against fraud and prevent legitimate participation, as well as which point of view voters find more compelling and whether or not attitudes towards voter identification are related to voter confidence. While most voters think that voter ID laws prevent fraud, many voters think that ensuring access to the polls is more important than preventing fraud. Among other variables that explain differences among individuals, partisanship plays an important role.Caltech/MIT Voting Technology Projec

Bore seal technology topical report

Thermophysical, compatibility, and mechanical properties of ceramic-to-metal bore seal material