Nondestructive testing of Scout rocket motors

The nondestructive tests applied to Scout rocket motors were reviewed and appraised. Analytical techniques were developed to evaluate the capabilities of the radiographic and ultrasonic procedures used. Major problem areas found were the inadequacy of high voltage radiography for detecting unbonds and propellant cracks having narrow widths, the inability to relate the ultrasonic signals received from flat-bottomed holes in standards to those received from real defects and in the general area of the specification of acceptance criteria and how these were to be met. To counter the deficiencies noted, analyses were conducted to the potential utility of radiometric, acoustic, holographic and thermographic techniques for motor and nozzle bond inspection, a new approach to qualifying magnetic particle inspection and the application of acoustic emission analysis to the evaluation of proof and leak test data

Marginal likelihoods in phylogenetics: a review of methods and applications

By providing a framework of accounting for the shared ancestry inherent to all life, phylogenetics is becoming the statistical foundation of biology. The importance of model choice continues to grow as phylogenetic models continue to increase in complexity to better capture micro and macroevolutionary processes. In a Bayesian framework, the marginal likelihood is how data update our prior beliefs about models, which gives us an intuitive measure of comparing model fit that is grounded in probability theory. Given the rapid increase in the number and complexity of phylogenetic models, methods for approximating marginal likelihoods are increasingly important. Here we try to provide an intuitive description of marginal likelihoods and why they are important in Bayesian model testing. We also categorize and review methods for estimating marginal likelihoods of phylogenetic models, highlighting several recent methods that provide well-behaved estimates. Furthermore, we review some empirical studies that demonstrate how marginal likelihoods can be used to learn about models of evolution from biological data. We discuss promising alternatives that can complement marginal likelihoods for Bayesian model choice, including posterior-predictive methods. Using simulations, we find one alternative method based on approximate-Bayesian computation (ABC) to be biased. We conclude by discussing the challenges of Bayesian model choice and future directions that promise to improve the approximation of marginal likelihoods and Bayesian phylogenetics as a whole.Comment: 33 pages, 3 figure

Submicrosecond comparisons of time standards via the Navigation Technology Satellites (NTS)

An interim demonstration was performed of the time transfer capability of the NAVSTAR GPS system using a single NTS satellite. Measurements of time difference (pseudo-range) are made from the NTS tracking network and at the participating observatories. The NTS network measurements are used to compute the NTS orbit trajectory. The central NTS tracking station has a time link to the Naval Observatory UTC (USNO,MC1) master clock. Measurements are used with the NTS receiver at the remote observatory, the time transfer value UTC (USNO,MC1)-UTC (REMOTE, VIA NTS) is calculated. Intercomparisons were computed using predicted values of satellite clock offset and ephemeus

Al-Hawārī’s commentary on Ibn al-Bannā’’s Talkhīs: Contents and influences

In 1305 al-Hawārī completed his commentary on Ibn al-Bannā’’s famous arithmetic book Talkhī½ṣ aþmāl al-¬isāb . This is the only commentary, apart from Ibn al-Bannā’’s own, to have been written during the author’s lifetime. What distinguishes al-Hawārī’s book from the numerous later commentaries is its focus on numerical examples of the rules of calculation. We present here what we know about the author, his book, its salient features, and its influences

Betty Jean Oaks Talking About Farm Life in Primera, Cameron County, Texas During 1920s and 1930s

An interview with Betty Jean (Hamilton) Oaks, an RGV community member, explores her experience in the border region. Conducted by Ruby Aguilar, a local school teacher participating in the Porciones to Colonias project. Betty Jean was born in 1925 in Primera, TX. Mrs. Oaks provides an overview of her genealogy and describes farm life in the Valley, providing details about crops and harvests, transportation, local businesses, and more. Betty J. Oaks was interviewed by Ruby A. Aguilar. Mayra Zepeda (videographer)https://scholarworks.utrgv.edu/chapsoralhistories/1109/thumbnail.jp

Improving Transformational Teaching and Learning by Advancing Higher Education Feedback-Based Dialogues at Texas A&M University

Feedback mechanisms are critical to iteratively improving most societal systems, and yet there is minimal documentation on the best practices of leveraging feedback to improve teaching and learning in higher education. We attest that facilitated dialogues have the potential to start conversations relevant to improving policy that otherwise would not transpire. In higher education, facilitated dialogues between students, faculty, staff, and administration provide a unique face-to-face opportunity for all participants to provide feedback to one another on real-time institutional strengths and weaknesses. More specifically, facilitated dialogues have the potential to start a conversation on improving the learning in higher education. This work notes the theory facilitated dialogues and offers discussion on the long-term potential for such conversations to serve as a medium for iterative feedback in larger societal systems. Further, this thesis documents our development of a facilitated dialogue, The Student-Faculty Dialogue, which will act as a plenary event at Texas A&M’s inaugural Transformational Teaching and Learning Conference on April 17, 2018

TALDO1 (transaldolase 1)

Short communication on TALDO1, with data on DNA/RNA, on the protein encoded and where the gene is implicated