Creep-Rupture and Fatigue Behaviors of Notched Oxide/Oxide Ceramic Matrix Composite at Elevated Temperature

Oxide/oxide composites are being considered for use in high temperature aerospace applications where their inherent resistance to oxidation provides for better long life properties at high temperature than most other ceramic matrix composites (CMCs). One promising oxide/oxide CMC is Nextel 720/A (N720/A) which uses an 8-harness satin weave (8HSW) of Nextel 720 fibers embedded in a porous alumina matrix. Possible aerospace applications for N720/A will likely require inserting holes into the material for mounting and cooling purposes. The notch characteristics must be understood to ensure designs using the material are sufficient for the desired application. This research effort examined the fatigue and creep-rupture characteristics of N720/A with a 0 /90 fiber orientation and notch to width ratio (2a/w) of 0.33. Specifically, 12.0 mm wide rectangular specimens with a 4.0 mm center hole were subjected to axial fatigue and creep-rupture loads in 1200 C laboratory air. Monotonic tensile tests at 1200 C were performed on unnotched specimens to provide a baseline for comparison with previous research. Fracture surfaces were examined under microscope to observe microstructure and damage mechanisms. Comparisons to previous unnotched research results at 1200 C show N720/A to be primarily insensitive to 0.33 notch ratios

The Military Divorce: An Overview

Your Court Review Editors asked Mark Sullivan, nationally known expert on the military divorce, to contribute an article to this journal. Mark recruited colleagues Joe DeWoskin of Kansas City, KS, a retired Army officer, and Kansas District Court Judge Dan Wiley, who presides over domestic relations cases, to assist him. What follows is their round table discussion of the key issues in a military divorce

Soft body animation in real-time simulations

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 75-76).This thesis presents a novel approach for creating deformable object animations. A deformable object can be represented as a discrete lattice of particles, and transforming those particles defines a new state for the represented object. By applying shape matching techniques, we are able to adapt traditional mesh based animations to this representation. We then allow these particles to take place in a soft body physics simulation. By making the particles track positions defined in the animation, soft body tracking of user created animation has been made possible.by Mark A. Sullivan III.M.Eng

Single-object Imaging and Spectroscopy to Enhance Dark Energy Science from LSST

Single-object imaging and spectroscopy on telescopes with apertures ranging from ~4 m to 40 m have the potential to greatly enhance the cosmological constraints that can be obtained from LSST. Two major cosmological probes will benefit greatly from LSST follow-up: accurate spectrophotometry for nearby and distant Type Ia supernovae will expand the cosmological distance lever arm by unlocking the constraining power of high-z supernovae; and cosmology with time delays of strongly-lensed supernovae and quasars will require additional high-cadence imaging to supplement LSST, adaptive optics imaging or spectroscopy for accurate lens and source positions, and IFU or slit spectroscopy to measure detailed properties of lens systems. We highlight the scientific impact of these two science drivers, and discuss how additional resources will benefit them. For both science cases, LSST will deliver a large sample of objects over both the wide and deep fields in the LSST survey, but additional data to characterize both individual systems and overall systematics will be key to ensuring robust cosmological inference to high redshifts. Community access to large amounts of natural-seeing imaging on ~2-4 m telescopes, adaptive optics imaging and spectroscopy on 8-40 m telescopes, and high-throughput single-target spectroscopy on 4-40 m telescopes will be necessary for LSST time domain cosmology to reach its full potential. In two companion white papers we present the additional gains for LSST cosmology that will come from deep and from wide-field multi-object spectroscopy.Comment: Submitted to the call for Astro2020 science white paper

Depression predicts revascularization procedures for 5 years after coronary angiography.

OBJECTIVE:Depression has been reported to increase cardiac event rates and functional impairment in patients with coronary disease. This article describes the impact of depression on subsequent healthcare utilization for such patients. METHODS:One hundred ninety-eight health maintenance organization patients with stable coronary disease were interviewed after elective angiography using a structured psychiatric diagnostic scale. Cardiac events, hospitalizations, procedures, and costs were monitored for the next 5 years through automated data. Subjects were classified at the time of angiography by modified DSM-IV criteria into those with major, minor, and no depression. RESULTS:In univariate analyses, the no depression group (N = 136) was most likely to receive coronary artery bypass grafting (CABG) (61% vs. 36% in the major depression group vs. 27% in the minor depression group, p =.001), and the major depression group (N = 25) was most likely to receive percutaneous transluminal coronary angioplasty (PTCA) (44% vs. 14% in the minor depression group vs. 24% in the no depression group). The minor depression group (N = 37) was least likely to be hospitalized for cardiac reasons during follow-up (54% vs. 80% in the major depression group vs. 80% in the no depression group, p =.005). Five-year rates of myocardial infarction and death did not differ significantly between groups. Proportional hazard models showed that those in the depression groups differed in time from catheterization to CABG (chi2(2) = 11.9, p =.003) and time to PCTA (chi2(2) = 7.74, p =.02) after controlling for relevant covariates. Median regression showed that patients with no depression had higher costs during the first year but tended to have lower costs in years 2 through 5 than patients with minor or major depression. CONCLUSIONS:Depression status at angiography is associated with the need for revascularization and total healthcare costs for the following year

A detailed study of the diastereoselective catalytic hydrogenation of 6-hydroxytetrahydroisoquinoline-(3R)-carboxylic ester intermediates

A key step towards a highly-selective antagonist of ionotropic glutamate receptors entails the diastereoselective arene hydrogenation of an enantiopure tetrahydroisoquinoline. An extensive screen using parallel reactors was conducted and led to the discovery of several Pd/C catalysts giving high yield and improved diastereoselectivity from 75 : 25 to 95 : 5. A detailed kinetic study of the best system was performed and supports the reduction occuring in two-steps.

The impact of deliberate reflection with WISE-MD modules on surgical clerkship students\u27 critical thinking: a prospective, randomized controlled pilot study

Purpose: Critical thinking underlies several Association of American Medical Colleges (AAMC)-defined core entrustable professional activities (EPAs). Critical-thinking ability affects health care quality and safety. Tested tools to teach, assess, improve, and nurture good critical-thinking skills are needed. This prospective randomized controlled pilot study evaluated the addition of deliberate reflection (DR), guidance with Web Initiative in Surgical Education (WISE-MD) modules, to promote surgical clerks\u27 critical-thinking ability. The goal was to promote the application of reflective awareness principles to enhance learning outcomes and critical thinking about the module content. Participants and methods: Surgical clerkship (SC) students were recruited from two different blocks and randomly assigned to a control or intervention group. The intervention group was asked to record responses using a DR guide as they viewed two selected WISE-MD modules while the control group was asked to view two modules recording free thought. We hypothesized that the intervention group would show a significantly greater pre- to postintervention increase in critical-thinking ability than students in the control group. Results: Neither group showed a difference in pre- and posttest free-thought critical-thinking outcomes; however, the intervention group verbalized more thoughtful clinical reasoning during the intervention. Conclusion: Despite an unsupported hypothesis, this study provides a forum for discussion in medical education. It took a sponsored tool in surgical education (WISE-MD) and posed the toughest evaluation criteria of an educational intervention; does it affect the way we think? and not just what we learn, but how we learn it? The answer is significant and will require more resources before we arrive at a definitive answer

A Visual Impact Assessment Methodology for the National Park Service

As the National Park Service (NPS) set out to create a visual resource management program, the first major component was the development of a robust visual resource inventory (VRI) process to identify, locate, and assess high value views, both within and near NPS units, based on both scenic quality and the importance of the view to the visitor experience. The next component in the program has been the development of a visual impact assessment (VIA) process to understand how changes in the landscape— whether inside the park or beyond its boundaries—could impact the scenic quality of valued views and visitor experience of those views. This presentation will discuss the NPS VIA process and highlight results of field-testing. Units of the National Park System encompass a wide variety of landscape types and visual settings. Particular views are enjoyed not only for scenic qualities but also appreciated for their historic and cultural values. NPS incorporates visible elements of views into their interpretive and educational activities. As a result, the NPS VRI was designed to identify not only the visual qualities of views but also the other values that make views important to NPS and park visitors. The NPS VRI was also built to support VIAs, both for NPS projects and actions within NPS unit boundaries, and projects and activities beyond NPS unit boundaries, where NPS is a stakeholder rather than a permitting agency. The detailed information from the VRI provides a sound basis for articulating the full effects of a proposed project or activity, which may go far beyond measuring visual contrast and other more purely scenic aspects of visual impact. Building on the inventory process the NPS visual impact assessment (VIA) methodology identifies the expected level of visual change from a proposed project or activity, and assesses the likely effects of the change on scenic quality as determined in the VRI. The NPS VIA approach provides parks with information to pursue better planning and design for park projects and credible support for understanding and communicating the potential impacts of changes beyond park boundaries