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The engineering diffractometer 2nd Generation Neutron Residual Stress Facility (NRSF2) at the Oak Ridge National Laboratory's High Flux Isotope Reactor was built specifically for the mapping of residual strains. NRSF2 is optimized to investigate a wide range of engineering materials by providing the user a selection of monochromatic neutron wavelengths to maintain the selected Bragg reflection near 2θ = 90°, which is the optimal scattering geometry for strain mapping. Details of the instrument configuration and operation are presented, and considerations for experimental planning are also discussed. Selected examples of recent residual stress work completed with NRSF2 are presented to highlight capabilities.

Improving communication with an adolescent with a life-limiting or life-threatening disease is key to providing comprehensive care and support. A pediatric hospital in the Midwest uses a communication tool (CCCT) to facilitate conversations about the adolescent's wishes, beliefs, values, preferences and goals. Information gathered in a CCCT conversation becomes a key intervention to providing compassionate, appropriate care that is directed toward quality of life consistent with the adolescent's and family's goals., (Copyright 2010 National Association of Pediatric Nurse Practitioners. Published by Mosby, Inc. All rights reserved.)

Patients with previous adverse contrast reactions occasionally present with ST-segment elevation myocardial infarction. Whether they can undergo catheterization safely using current contrast and medications is unknown. We reviewed catheterization laboratory records of all 501 patients (January 2005 to December 2006) presenting with ST-segment elevation myocardial infarction who underwent emergency coronary angiography. Six patients (1.2%) reported a previous contrast reaction including rash, acute bronchospasm, or anaphylaxis. All received a combination of intravenous steroids and H1 and H2 blockers in the emergency department or catheterization laboratory before catheterization. None of these had complications or evidence of allergy in any patient. In conclusion, some patients with previous contrast reaction may undergo emergency catheterization without adverse consequences, although the safety of this approach has not been proved.

We present the case of a young woman who developed an acute onset of classic cardiac symptoms, but because of her age and lack of risk factors, had a significant delay in transfer for cardiac catheterization. She was found to have spontaneous dissection of the left coronary system, eventually requiring emergent bypass surgery. The patient had recently began her menstrual period, and we speculate that hormonal fluctuations contributed to this process. The role of hormonal influences on the coronary vasculature is not entirely understood, but the incidence of spontaneous coronary dissection is higher in women, and is usually related to changes in hormones such as pregnancy and oral contraceptive use. We review the literature on spontaneous coronary dissection, the influence of hormones on the vasculature, as well as diagnosis and treatment options.

The Research Associateship program of the Joint Committee on Powder Diffraction-International Centre for Diffraction Data (JCPDS-ICDD, now known as the ICDD) at NBS/NIST was a long standing (over 35 years) successful industry-government cooperation. The main mission of the Associateship was to publish high quality x-ray reference patterns to be included in the Powder Diffraction File (PDF). The PDF is a continuing compilation of patterns gathered from many sources, compiled and published by the ICDD. As a result of this collaboration, more than 1500 high quality powder diffraction patterns, which have had a significant impact on the scientific community, were reported. In addition, various research collaborations with NBS/NIST also led to the development of several standard reference materials (SRMs) for instrument calibration and quantitative analyses, and computer software for data collection, calibration, reduction, for the editorial process of powder pattern publication, analysis of powder data, and for quantitative analyses. This article summarizes information concerning the JCPDS-ICDD organization, the Powder Diffraction File (PDF), history and accomplishments of the JCPDS-ICDD Research Associateship.

An international project was successfully completed which involved two major undertakings: (1) a round-robin to demonstrate the viability of the selected standard and (2) the certification of the lattice parameters of the SRM 1990, a Standard Reference Material(®) for single crystal diffractometer alignment. This SRM is a set of ≈3500 units of Cr-doped Al2O3, or ruby spheres [(0.420.011 mole fraction % Cr (expanded uncertainty)]. The round-robin consisted of determination of lattice parameters of a pair of crystals: the ruby sphere as a standard, and a zeolite reference to serve as an unknown. Fifty pairs of crystals were dispatched from Hauptman-Woodward Medical Research Institute to volunteers in x-ray laboratories world-wide. A total of 45 sets of data was received from 32 laboratories. The mean unit cell parameters of the ruby spheres was found to be a=4.7608 ű0.0062 Å, and c=12.9979 ű0.020 Å (95 % intervals of the laboratory means). The source of errors of outlier data was identified. The SRM project involved the certification of lattice parameters using four well-aligned single crystal diffractometers at (Bell Laboratories) Lucent Technologies and at NRC of Canada (39 ruby spheres), the quantification of the Cr content using a combined microprobe and SEM/EDS technique, and the evaluation of the mosaicity of the ruby spheres using a double-crystal spectrometry method. A confirmation of the lattice parameters was also conducted using a Guinier-Hägg camera. Systematic corrections of thermal expansion and refraction corrections were applied. These rubies- are rhombohedral, with space group [Formula: see text]. The certified mean unit cell parameters are a=4.76080±0.00029 Å, and c=12.99568 ű0.00087 Å (expanded uncertainty). These certified lattice parameters fall well within the results of those obtained from the international round-robin study. The Guinier-Hägg transmission measurements on five samples of powdered rubies (a=4.7610 ű0.0013 Å, and c = 12.9954 ű0.0034 Å) agreed well with the values obtained from the single crystal spheres.

Objective: To define the growth pattern of girls with Rett syndrome with respect to height, weight, and fronto-occipital head circumference., Design: Longitudinal with irregular intervals between measurements., Setting: Rett Syndrome Program Project at Baylor College of Medicine, Houston, Tex., Participants: Ninety-six girls fulfilling criteria for Rett syndrome; comparison group with standard growth curves., Selection Procedure: Consecutive entries into the Rett Syndrome Program Project., Intervention: None., Measurements/main Results: Height, weight, and fronto-occipital head circumference data were grouped into intervals. Group medians were then generated. Regression lines were fitted through the median points and plotted on standard growth charts. Deceleration of growth velocities began at age 3 months and persisted through age 18 years., Conclusions: Early deceleration of head growth, followed by deceleration of weight and height measurements, appears to be a growth pattern characteristic of Rett syndrome. This pattern of growth may provide the earliest clinical indicator for the diagnosis of Rett syndrome.

C 11 N 4 O 3 K 2 · 2H 2 O crystallizes in the triclinic space group P 1 ¯ with a = 8.568(2), b = 9.105(4), c = 9.818(4)Å, α = 103.61(3), β = 107.63(3), γ = 101.58(3)°; Z = 2, ρ calc = 1.716, ρ obs = 1.72(2)g cm -3 (flotation). The structure was solved by direct methods and was refined by full-matrix least-squares procedures to a final R of 0.074 for 1989 observed reflections. The five-membered ring is planar and pentagonal. The two = C(CN) 2 groups define separate planes which form angles of 3.36 and 6.30° with the plane of the five-membered ring. The dianions form stacks along the a-axis. In a given stack, there is an alternating sequence of perpendicular distances (3.32, 3.42Å) between the planes defined by the ring atoms.

C 27 H 20 N 2 O 3 , MW = 420, orthorhombic, Pbc2 1 , a = 4.686(2), b = 16.784(8), c = 25.924(10)Å, V = 2039Å 3 , d obs = 1.37 g cm -3 (flotation), d calc = 1.369g cm -3 , Z = 4. The structure has been determined by direct methods and refined to R = 0.045 based on 1419 independent reflections. No crystallographic symmetry element is present in the dixanthylurea molecule. In fact, the molecule is considerably distorted from any possible mirror symmetry. The molecules are hydrogen bonded in an infinite chain along the a -axis. The compound is of interest because of its role in the analytical determination of urea.

The development of a computerized database on advanced structural ceramics can play a critical role in fostering the widespread use of ceramics in industry and in advanced technologies. A computerized database may be the most effective means of accelerating technology development by enabling new materials to be incorporated into designs far more rapidly than would have been possible with traditional information transfer processes. Faster, more efficient access to critical data is the basis for creating this technological advantage. Further, a computerized database provides the means for a more consistent treatment of data, greater quality control and product reliability, and improved continuity of research and development programs. A preliminary system has been completed as phase one of an ongoing program to establish the Structural Ceramics Database system. The system is designed to be used on personal computers. Developed in a modular design, the preliminary system is focused on the thermal properties of monolithic ceramics. The initial modules consist of materials specification, thermal expansion, thermal conductivity, thermal diffusivity, specific heat, thermal shock resistance, and a bibliography of data references. Query and output programs also have been developed for use with these modules. The latter program elements, along with the database modules, will be subjected to several stages of testing and refinement in the second phase of this effort. The goal of the refinement process will be the establishment of this system as a user-friendly prototype. Three primary considerations provide the guidelines to the system's development: (1) The user's needs; (2) The nature of materials properties; and (3) The requirements of the programming language. The present report discusses the manner and rationale by which each of these considerations leads to specific features in the design of the system.