Elasticity of plagioclase feldspars

AbstractElastic properties are reported for eight plagioclase feldspars that span compositions from albite (NaSi3AlO8) to anorthite (CaSi2Al2O8). Surface acoustic wave velocities measured using Impulsive Stimulated Light Scattering and compliance sums from high‐pressure X‐ray compression studies accurately determine all 21 components of the elasticity tensor for these triclinic minerals. The overall pattern of elasticity and the changes in individual elastic components with composition can be rationalized on the basis of the evolution of crystal structures and chemistry across this solid‐solution join. All plagioclase feldspars have high elastic anisotropy; a* (the direction perpendicular to the b and c axes) is the softest direction by a factor of 3 in albite. From albite to anorthite the stiffness of this direction undergoes the greatest change, increasing twofold. Small discontinuities in the elastic components, inferred to occur between the three plagioclase phases with distinct symmetry ( , , and ), appear consistent with the nature of the underlying conformation of the framework‐linked tetrahedra and the associated structural changes. Measured body wave velocities of plagioclase‐rich rocks, reported over the last five decades, are consistent with calculated Hill‐averaged velocities using the current moduli. This confirms long‐standing speculation that previously reported elastic moduli for plagioclase feldspars are systematically in error. The current results provide greater assurance that the seismic structure of the middle and lower crusts can be accurately estimated on the basis of specified mineral modes, chemistry, and fabric

Differential Discourse Patterns in Mainstream Versus First Nations Students in an Adult Basic Education Classroom

The purpose of this study was to record and transcribe a lesson conducted in the Initiation-Response-Evaluation (IRE) style, in order to examine the patterns of interaction between teacher and students, focusing on ways in which the teacher differentiates between First Nations and non-First Nations students, and on ways in which their discourse differs. I chose to use one of my own classes, and to examine my own interactions, in order to discover my role in these student-teacher interactions. What differences can be seen in the quantity and quality of student utterances between First Nations and mainstream students? How do I, as the teacher, treat students, and do I treat First Nations students differently? What am I doing that may cause differences, and how do I react to differences? How does the IRE style of the lesson impact upon student contributions? What is occurring that maintains or reinforces inequalities of knowledge and skills? In sum, I wanted to examine my role in the classroom more closely, in the hope that I could use any findings to improve my practice

Pediatric emergency medical care in Yerevan, Armenia: a knowledge and attitudes survey of out-of-hospital emergency physicians.

BACKGROUND: Out-of-hospital emergency care is at an early stage of development in Armenia, with the current emergency medical services (EMS) system having emergency physicians (EPs) work on ambulances along with nurses. While efforts are underway by the Ministry of Health and other organizations to reform the EMS system, little data exists on the status of pediatric emergency care (PEC) in the country. We designed this study to evaluate the knowledge and attitudes of out-of-hospital emergency physicians in pediatric rapid assessment and resuscitation, and identify areas for PEC improvement. METHODS: We distributed an anonymous, self-administered Knowledge and Attitudes survey to a convenience sample of out-of-hospital EPs in the capital, Yerevan, from August to September 2012. RESULTS: With a response rate of 80%, the majority (89.7%) of respondents failed a 10-question knowledge test (with a pre-defined passing score of ≥7) with a mean score of 4.17 ± 1.99 SD. Answers regarding the relationship between pediatric cardiac arrest and respiratory issues, compression-to-ventilation ratio in neonates, definition of hypotension, and recognition of shock were most frequently incorrect. None of the participants had attended pediatric-specific continuing medical education (CME) activities within the preceding 5 years. χ2 analysis demonstrated no statistically significant association between physician age, length of EMS experience, type of ambulance (general vs. resuscitation/critical care), or CME attendance and pass/fail status. The majority of participants agreed that PEC education in Armenia needs improvement (98%), that there is a need for pediatric-specific CME (98%), and that national out-of-hospital PEC guidelines would increase PEC safety, efficiency, and effectiveness (96%). CONCLUSIONS: Out-of-hospital emergency physicians in Yerevan, Armenia are deficient in pediatric-specific emergency assessment and resuscitation knowledge and training, but express a clear desire for improvement. There is a need to support additional PEC training and CME within the EMS system in Armenia

Electronic and Structural Properties of a 4d-Perovskite: Cubic Phase of SrZrO3_3

First-principles density functional calculations are performed within the local density approximation to study the electronic properties of SrZrO$_3$, an insulating 4d-perovskite, in its high-temperature cubic phase, above 1400 K, as well as the generic 3d-perovskite SrTiO$_3$, which is also a d^0-insulator and cubic above 105 K, for comparison reasons. The energy bands, density of states and charge density distributions are obtained and a detailed comparison between their band structures is presented. The results are discussed also in terms of the existing data in the literature for both oxides.Comment: 5 pages, 2 figure

Evaluating Cognition in Individuals with Huntington Disease: NeuroQoL Cognitive Functioning Measures

PURPOSE: Cognitive functioning impacts health-related quality of life (HRQOL) for individuals with Huntington disease (HD). The Neuro-QoL includes two patient-reported outcome (PRO) measures of cognition-Executive Function (EF) and General Concerns (GC). These measures have not previously been validated for use in HD. The purpose of this analysis is to evaluate the reliability and validity of the Neuro-QoL Cognitive Function measures for use in HD. METHODS: Five hundred ten individuals with prodromal or manifest HD completed the Neuro-QoL Cognition measures, two other PRO measures of HRQOL (WHODAS 2.0 and EQ5D), and a depression measure (PROMIS Depression). Measures of functioning The Total Functional Capacity and behavior (Problem Behaviors Assessment) were completed by clinician interview. Objective measures of cognition were obtained using clinician-administered Symbol Digit Modalities Test and the Stroop Test (Word, Color, and Interference). Self-rated, clinician-rated, and objective composite scores were developed. We examined the Neuro-QoL measures for reliability, convergent validity, discriminant validity, and known-groups validity. RESULTS: Excellent reliabilities (Cronbach\u27s alphas ≥ 0.94) were found. Convergent validity was supported, with strong relationships between self-reported measures of cognition. Discriminant validity was supported by less robust correlations between self-reported cognition and other constructs. Prodromal participants reported fewer cognitive problems than manifest groups, and early-stage HD participants reported fewer problems than late-stage HD participants. CONCLUSIONS: The Neuro-QoL Cognition measures provide reliable and valid assessments of self-reported cognitive functioning for individuals with HD. Findings support the utility of these measures for assessing self-reported cognition

Improvements in forecasting intense rainfall: results from the FRANC (forecasting rainfall exploiting new data assimilation techniques and novel observations of convection) project

The FRANC project (Forecasting Rainfall exploiting new data Assimilation techniques and Novel observations of Convection) has researched improvements in numerical weather prediction of convective rainfall via the reduction of initial condition uncertainty. This article provides an overview of the project’s achievements. We highlight new radar techniques: correcting for attenuation of the radar return; correction for beams that are over 90% blocked by trees or towers close to the radar; and direct assimilation of radar reflectivity and refractivity. We discuss the treatment of uncertainty in data assimilation: new methods for estimation of observation uncertainties with novel applications to Doppler radar winds, Atmospheric Motion Vectors, and satellite radiances; a new algorithm for implementation of spatially-correlated observation error statistics in operational data assimilation; and innovative treatment of moist processes in the background error covariance model. We present results indicating a link between the spatial predictability of convection and convective regimes, with potential to allow improved forecast interpretation. The research was carried out as a partnership between University researchers and the Met Office (UK). We discuss the benefits of this approach and the impact of our research, which has helped to improve operational forecasts for convective rainfall event

The International Surface Pressure Databank version 2

The International Surface Pressure Databank (ISPD) is the world's largest collection of global surface and sea-level pressure observations. It was developed by extracting observations from established international archives, through international cooperation with data recovery facilitated by the Atmospheric Circulation Reconstructions over the Earth (ACRE) initiative, and directly by contributing universities, organizations, and countries. The dataset period is currently 1768–2012 and consists of three data components: observations from land stations, marine observing systems, and tropical cyclone best track pressure reports. Version 2 of the ISPD (ISPDv2) was created to be observational input for the Twentieth Century Reanalysis Project (20CR) and contains the quality control and assimilation feedback metadata from the 20CR. Since then, it has been used for various general climate and weather studies, and an updated version 3 (ISPDv3) has been used in the ERA-20C reanalysis in connection with the European Reanalysis of Global Climate Observations project (ERA-CLIM). The focus of this paper is on the ISPDv2 and the inclusion of the 20CR feedback metadata. The Research Data Archive at the National Center for Atmospheric Research provides data collection and access for the ISPDv2, and will provide access to future versions

Delta-Sarcoglycan Gene Therapy Halts Progression of Cardiac Dysfunction, Improves Respiratory Failure, and Prolongs Life in Myopathic Hamsters

The BIO14.6 hamster provides a useful model of hereditary cardiomyopathies and muscular dystrophy. Previous delta-sarcoglycan (δSG) gene therapy (GT) studies were limited to neonatal and young adult animals, and prevented the development of cardiac and skeletal muscle dysfunction. GT of a pseudo-phosphorylated mutant of phospholamban (S16EPLN) moderately alleviated the progression of cardiomyopathy