Analysis Tools for Discovering Strong Parity Violation at Hadron Colliders

Several arguments suggest parity violation may be observable in high energy strong interactions. We introduce new analysis tools for describing the azimuthal dependence of multi-particle distributions, or "azimuthal flow." Analysis uses the representations of the orthogonal group O(2) and dihedral groups $D_{N}$ necessary to define parity correctly in two dimensions. Classification finds that collective angles used in event-by-event statistics represent inequivalent tensor observables that cannot generally be represented by a single "reaction plane". Many new parity-violating observables exist that have never been measured, while many new parity-conserving observables formerly lumped together are now distinguished. We use the concept of "event shape sorting" to suggest separating right- and left-handed events, and we discuss the effects of transverse and longitudinal spin. The analysis tools are statistically robust, and can be applied equally to low or high multiplicity events at the Tevatron, $RHIC$ or $RHIC\, Spin$, and the $LHC$.Comment: 18 pages, 2 figures. Final version, accepted for publication in PRD. Updated references. Modified presentation and discussion of previous wor

Tablet PCs in schools: Case study report: A report for Becta by the Open University

The publication provides an analysis of twelve case studies involving schools in England that were using Tablet PCs. The analysis is complemented by brief individual reports describing aspects of how each of these schools was using Tablet PCs

The Nucleon ``Tensor Charges'' and the Skyrme Model

The lowest moment of the twist-two, chiral-odd parton distribution $h_1(x)$ of the nucleon can be related to the so-called ``tensor charges'' of the nucleon. We consider the tensor charges in the Skyrme model, and find that in the large-$N_c$, SU(3)-symmetric limit, the model predicts that the octet isosinglet tensor charge, $g^8_T$, is of order $1/N_c$ with respect to the octet isovector tensor charge, $g^3_T$. The predicted $F/D$ ratio is then 1/3, in the large-$N_c$ limit. These predictions coincide with the Skyrme model predictions for the octet ${\it axial}$ charges, $g^8_A$ and $g^3_A$. (The prediction $F/D=1/3$ for the axial charges differs from the commonly quoted prediction of 5/9, which is based on an inconsistent treatment of the large-$N_c$ limit.) The model also predicts that the singlet tensor charge, $g^0_T$, is of order $1/N_c$ with respect to $g^3_T$.Comment: 9 single-spaced pages, no figures, MIT-CTP-212

Temperature and residence time controls on an estuarine harmful algal bloom : modeling hydrodynamics and Alexandrium fundyense in Nauset estuary

Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Estuaries and Coasts 38 (2015): 2240-2258, doi:10.1007/s12237-015-9949-z.A highly resolved, 3-d model of hydrodynamics and Alexandrium fundyense in an estuarine embayment has been developed to investigate the physical and biological controls on a recurrent harmful algal bloom. Nauset estuary on Cape Cod (MA, USA) consists of three salt ponds connected to the ocean through a shallow marsh and network of tidal channels. The model is evaluated using quantitative skill metrics against observations of physical and biological conditions during three spring blooms. The A. fundyense model is based on prior model applications for the nearby Gulf of Maine, but notable modifications were made to be consistent with the Nauset observations. The dominant factors controlling the A. fundyense bloom in Nauset were the water temperature, which regulates organism growth rates, and the efficient retention of cells due to bathymetric constraints, stratification, and cell behavior (diel vertical migration). Spring-neap variability in exchange altered residence times, but for cell retention to be substantially longer than the cell doubling time required both active vertical migration and stratification that inhibits mixing of cells into the surface layer by wind and tidal currents. Unlike in the Gulf of Maine, the model results were relatively insensitive to cyst distributions or germination rates. Instead, in Nauset, high apparent rates of vegetative cell division by retained populations dictated bloom development. Cyst germination occurred earlier in the year than in the Gulf of Maine, suggesting that Nauset cysts have different controls on germination timing. The model results were relatively insensitive to nutrient concentrations, due to eutrophic conditions in the highly impacted estuary or due to limitations in the spatial and temporal resolution of nutrient sampling. Cell loss rates were inferred to be extremely low during the growth phase of the bloom, but increased rapidly during the final phase due to processes that remain uncertain. The validated model allows a quantitative assessment of the factors that contribute to the development of a recurrent harmful algal bloom and provides a framework for assessing similarly impacted coastal systems.This work was supported by the National Science Foundation (OCE-0430724, OCE-0911031, and OCE-1314642) and National Institutes of Health (NIEHS-1P50-ES021923-01) through the Woods Hole Center for Oceans and Human Health, and by National Park Service (NPS) Cooperative Agreement H238015504.2016-03-1

Radio Detection of High Energy Particles: Coherence Versus Multiple Scales

Radio Cherenkov emission underlines detection of high energy particles via a signal growing like the particle-energy-squared. Cosmic ray-induced electromagnetic showers are a primary application. While many studies have treated the phenomenon approximately, none have attempted to incorporate all the physical scales involved in problems with time- or spatially- evolving charges. We find it is possible to decompose the calculated fields into the product of a form factor, characterizing a moving charge distribution, multiplying a general integral which depends on the charge evolution. In circumstances of interest for cosmic ray physics, the resulting expressions can be evaluated explicitely in terms of a few parameters obtainable from shower codes. The classic issues of Frauhofer and Fresnel zones play a crucial role in the coherence.Comment: 25 pages, 10 figure

Evaluating the impact of patients' online access to doctors' visit notes: designing and executing the OpenNotes project

Background: Providers and policymakers are pursuing strategies to increase patient engagement in health care. Increasingly, online sections of medical records are viewable by patients though seldom are clinicians' visit notes included. We designed a one-year multi-site trial of online patient accessible office visit notes, OpenNotes. We hypothesized that patients and primary care physicians (PCPs) would want it to continue and that OpenNotes would not lead to significant disruptions to doctors' practices. Methods/Design: Using a mixed methods approach, we designed a quasi-experimental study in 3 diverse healthcare systems in Boston, Pennsylvania, and Seattle. Two sites had existing patient internet portals; the third used an experimental portal. We targeted 3 key areas where we hypothesized the greatest impacts: beliefs and attitudes about OpenNotes, use of the patient internet portals, and patient-doctor communication. PCPs in the 3 sites were invited to participate in the intervention. Patients who were registered portal users of participating PCPs were given access to their PCPs' visit notes for one year. PCPs who declined participation in the intervention and their patients served as the comparison groups for the study. We applied the RE-AIM framework to our design in order to capture as comprehensive a picture as possible of the impact of OpenNotes. We developed pre- and post-intervention surveys for online administration addressing attitudes and experiences based on interviews and focus groups with patients and doctors. In addition, we tracked use of the internet portals before and during the intervention. Results: PCP participation varied from 19% to 87% across the 3 sites; a total of 114 PCPs enrolled in the intervention with their 22,000 patients who were registered portal users. Approximately 40% of intervention and non-intervention patients at the 3 sites responded to the online survey, yielding a total of approximately 38,000 patient surveys. Discussion: Many primary care physicians were willing to participate in this "real world" experiment testing the impact of OpenNotes on their patients and their practices. Results from this trial will inform providers, policy makers, and patients who contemplate such changes at a time of exploding interest in transparency, patient safety, and improving the quality of care

Addendum to "Coherent radio pulses from GEANT generated electromagnetic showers in ice"

We reevaluate our published calculations of electromagnetic showers generated by GEANT 3.21 and the radio frequency pulses they produce in ice. We are prompted by a recent report showing that GEANT 3.21-modeled showers are sensitive to internal settings in the electron tracking subroutine. We report the shower and pulse characteristics obtained with different settings of GEANT 3.21 and with GEANT 4. The default setting of electron tracking in GEANT 3.21 we used in previous work speeds up the shower simulation at the cost of information near the end of the tracks. We find that settings tracking electron and positron to lower energy yield a more accurate calculation, a more intense shower, and proportionately stronger radio pulses at low frequencies. At high frequencies the relation between shower tracking algorithm and pulse spectrum is more complex. We obtain radial distributions of shower particles and phase distributions of pulses from 100 GeV showers that are consistent with our published results.Comment: 4 pages, 3 figure

Coherent Radio Pulses From GEANT Generated Electromagnetic Showers In Ice

Radio Cherenkov radiation is arguably the most efficient mechanism for detecting showers from ultra-high energy particles of 1 PeV and above. Showers occuring in Antarctic ice should be detectable at distances up to 1 km. We report on electromagnetic shower development in ice using a GEANT Monte Carlo simulation. We have studied energy deposition by shower particles and determined shower parameters for several different media, finding agreement with published results where available. We also report on radio pulse emission from the charged particles in the shower, focusing on coherent emission at the Cherenkov angle. Previous work has focused on frequencies in the 100 MHz to 1 GHz range. Surprisingly, we find that the coherence regime extends up to tens of Ghz. This may have substantial impact on future radio-based neutrino detection experiments as well as any test beam experiment which seeks to measure coherent Cherenkov radiation from an electromagnetic shower. Our study is particularly important for the RICE experiment at the South Pole.Comment: 44 pages, 29 figures. Minor changes made, reference added, accepted for publication in Phys. Rev.

Data visualization for truth maintenance in clinical decision support systems

Background and objectives The goal is to inform proactive initiatives to expand the knowledge base of clinical decision support systems. Design and setting We describe an initiative in which research informationists and health services researchers employ visualization tools to map logic models for clinical decision support within an electronic health record. Materials and methods We mapped relationships using software for social network analysis: NodeXL and CMAP. We defined relationships by shared observations, such as two Arden rules within medical logic modules that consider the same clinical observation, or by the presence of common keywords that were used to label rules according to standardized vocabularies. Results We studied the Child Health Improvement through Computer Automation (CHICA) system, an electronic medical record that contains 170 unique variables representing discrete clinical observations. These variables were used in 300 medical logic modules (MLM's) that prompted health care providers to deliver preventive counseling or otherwise served as clinical decision support. Using data visualization tools, we generated maps that illustrate connections, or lack thereof, between clinical topics within CHICA's MLMs. Conclusions The development of such maps may allow multiple disciplines commonly interacting over EMR platforms, and various perspectives (clinicians, programmers, informationists) to work more effectively as teams to refine the EMR by programming logic routines to address co-morbidities or other instances where domains of medical knowledge should be connected

Exclusive Hadronic Processes and Color Transparency

We review the current status of high energy exclusive processes and color transparency.Comment: 17 pages, 8 figures, based on talk given at International Symposium on Nuclear Physics, Mumbai, Dec 18-22, 200