Utilization of the Building-Block Approach in Structural Mechanics Research

In the last 20 years NASA has worked in collaboration with industry to develop enabling technologies needed to make aircraft safer and more affordable, extend their lifetime, improve their reliability, better understand their behavior, and reduce their weight. To support these efforts, research programs starting with ideas and culminating in full-scale structural testing were conducted at the NASA Langley Research Center. Each program contained development efforts that (a) started with selecting the material system and manufacturing approach; (b) moved on to experimentation and analysis of small samples to characterize the system and quantify behavior in the presence of defects like damage and imperfections; (c) progressed on to examining larger structures to examine buckling behavior, combined loadings, and built-up structures; and (d) finally moved to complicated subcomponents and full-scale components. Each step along the way was supported by detailed analysis, including tool development, to prove that the behavior of these structures was well-understood and predictable. This approach for developing technology became known as the "building-block" approach. In the Advanced Composites Technology Program and the High Speed Research Program the building-block approach was used to develop a true understanding of the response of the structures involved through experimentation and analysis. The philosophy that if the structural response couldn't be accurately predicted, it wasn't really understood, was critical to the progression of these programs. To this end, analytical techniques including closed-form and finite elements were employed and experimentation used to verify assumptions at each step along the way. This paper presents a discussion of the utilization of the building-block approach described previously in structural mechanics research and development programs at NASA Langley Research Center. Specific examples that illustrate the use of this approach are included from recent research and development programs for both subsonic and supersonic transports

Applying economic principles to health care.

Applying economic thinking to an understanding of resource use in patient care is challenging given the complexities of delivering health care in a hospital. Health-care markets lack the characteristics needed to determine a "market" price that reflects the economic value of resources used. However, resource allocation in a hospital can be analyzed by using production theory to determine efficient resource use. The information provided by hospital epidemiologists is critical to understanding health-care production processes used by a hospital and developing economic incentives to promote antibiotic effectiveness and infection control

First-Year Faculty of Color: Narratives about Entering the Academy

The experiences of first-year, tenure-track faculty have been missing in the literature about new or junior faculty. Furthermore, the extant literature about new faculty does not offer a critical outlook on how oppressive institutional structures shape how first-year faculty of color approach faculty work. Drawing from analytical narratives, the authors reframe how doctoral student socialization and new-faculty support systems are discussed, especially pertaining to first-year faculty of color. In doing so, and utilizing narrative inquiry as a methodological framework, the authors draw out the distinct voices of new faculty of color. The implications offered are important for scholars who study faculty experiences and for faculty advisors to doctoral students interested in the professoriate

Using Small-Area Analysis to Estimate County-Level Racial Disparities in Obesity Demonstrating the Necessity of Targeted Interventions

Data on the national and state levels is often used to inform policy decisions and strategies designed to reduce racial disparities in obesity. Obesity-related health outcomes are realized on the individual level, and policies based on state and national-level data may be inappropriate due to the variations in health outcomes within and between states. To examine county-level variation of obesity within states, we use a small-area analysis technique to fill the void for county-level obesity data by race. Five years of Behavioral Risk Factor Surveillance System data are used to estimate the prevalence of obesity by county, both overall and race-stratified. A modified weighting system is used based on demographics at the county level using 2010 census data. We fit a multilevel reweighted regression model to obtain county-level prevalence estimates by race. We compare the distribution of prevalence estimates of non-Hispanic Blacks to non-Hispanic Whites. For 25 of the 26 states included in our analysis there is a statistically significant difference between within-state county-level average obesity prevalence rates for non-Hispanic Whites and non-Hispanic Blacks. This study provides information needed to target disparities interventions and resources to the local areas with greatest need; it also identifies the necessity of doing so

Optical Follow-up of New SMC Wing Be/X-ray Binaries

We investigate the optical counterparts of recently discovered Be/X-ray binaries in the Small Magellanic Cloud. In total four sources, SXP101, SXP700, SXP348 and SXP65.8 were detected during the Chandra Survey of the Wing of the SMC. SXP700 and SXP65.8 were previously unknown. Many optical ground based telescopes have been utilised in the optical follow-up, providing coverage in both the red and blue bands. This has led to the classification of all of the counterparts as Be stars and confirms that three lie within the Galactic spectral distribution of known Be/X-ray binaries. SXP101 lies outside this distribution becoming the latest spectral type known. Monitoring of the Halpha emission line suggests that all the sources bar SXP700 have highly variable circumstellar disks, possibly a result of their comparatively short orbital periods. Phase resolved X-ray spectroscopy has also been performed on SXP65.8, revealing that the emission is indeed harder during the passage of the X-ray beam through the line of sight.Comment: 9 pages, 9 figures, 2 tables, accepted for publication in MNRA

Barriers and facilitators to cooking from 'scratch' using basic or raw ingredients: A qualitative interview study

BACKGROUND: Previous research has highlighted an ambiguity in understanding cooking related terminology and a number of barriers and facilitators to home meal preparation. However, meals prepared in the home still include convenience products (typically high in sugars, fats and sodium) which can have negative effects on health. Therefore, this study aimed to qualitatively explore: (1) how individuals define cooking from 'scratch', and (2) their barriers and facilitators to cooking with basic ingredients. METHODS: 27 semi-structured interviews were conducted with participants (aged 18-58 years) living on the island of Ireland, eliciting definitions of 'cooking from scratch' and exploring the reasons participants cook in a particular way. The interviews were professionally transcribed verbatim and Nvivo 10 was used for an inductive thematic analysis. RESULTS: Our results highlighted that although cooking from 'scratch' lacks a single definition, participants viewed it as optimal cooking. Barriers to cooking with raw ingredients included: 1) time pressures; (2) desire to save money; (3) desire for effortless meals; (4) family food preferences; and (5) effect of kitchen disasters. Facilitators included: 1) desire to eat for health and well-being; (2) creative inspiration; (3) ability to plan and prepare meals ahead of time; and (4) greater self-efficacy in one's cooking ability. CONCLUSIONS: Our findings contribute to understanding how individuals define cooking from 'scratch', and barriers and facilitators to cooking with raw ingredients. Interventions should focus on practical sessions to increase cooking self-efficacy; highlight the importance of planning ahead and teach methods such as batch cooking and freezing to facilitate cooking from scratch

Increasing intention to cook from basic ingredients: A randomised controlled study

The promotion of home cooking is a strategy used to improve diet quality and health. However, modern home cooking typically includes the use of processed food which can lead to negative outcomes including weight gain. In addition, interventions to improve cooking skills do not always explain how theory informed their design and implementation. The Behaviour Change Technique (BCT) taxonomy successfully employed in other areas has identified essential elements for interventions. This study investigated the effectiveness of different instructional modes for learning to cook a meal, designed using an accumulating number of BCTs, on participant's perceived difficulty, enjoyment, confidence and intention to cook from basic ingredients. 141 mothers aged between 20 and 39 years from the island of Ireland were randomised to one of four conditions based on BCTs (1) recipe card only [control condition]; (2) recipe card plus video modelling; (3) recipe card plus video prompting; (4) recipe card plus video elements. Participants rated their enjoyment, perceived difficulty, confidence and intention to cook again pre, mid and post experiment. Repeated one-way factorial ANOVAs, correlations and a hierarchical regression model were conducted. Despite no significant differences between the different conditions, there was a significant increase in enjoyment (P < 0.001), confidence (P < 0.001) and intention to cook from basics again (P < 0.001) and a decrease in perceived difficulty (P = 0.001) after the experiment in all conditions. Intention to cook from basics pre-experiment, and confidence and enjoyment (both pre and post experiment) significantly contributed to the final regression model explaining 42% of the variance in intention to cook from basics again. Cooking interventions should focus on practical cooking and increasing participants' enjoyment and confidence during cooking to increase intention to cook from basic ingredients at home

Detection statistics in the micromaser

We present a general method for the derivation of various statistical quantities describing the detection of a beam of atoms emerging from a micromaser. The user of non-normalized conditioned density operators and a linear master equation for the dynamics between detection events is discussed as are the counting statistics, sequence statistics, and waiting time statistics. In particular, we derive expressions for the mean number of successive detections of atoms in one of any two orthogonal states of the two-level atom. We also derive expressions for the mean waiting times between detections. We show that the mean waiting times between de- tections of atoms in like states are equivalent to the mean waiting times calculated from the uncorrelated steady state detection rates, though like atoms are indeed correlated. The mean waiting times between detections of atoms in unlike states exhibit correlations. We evaluate the expressions for various detector efficiencies using numerical integration, reporting re- sults for the standard micromaser arrangement in which the cavity is pumped by excited atoms and the excitation levels of the emerging atoms are measured. In addition, the atomic inversion and the Fano-Mandel function for the detection of de-excited atoms is calculated for compari- son to the recent experimental results of Weidinger et al. [1], which reports the first observation of trapping states.Comment: 26 pages, 11 figure