Ion beam characterization of advanced luminescent materials for application in radiation effects microscopy

The ion photon emission microscope (IPEM) is a technique developed at Sandia National Laboratories (SNL) to study radiation effects in integrated circuits with high energy, heavy ions, such as those produced by the 88” cyclotron at Lawrence Berkeley National Laboratory (LBNL). In this method, an ion-luminescent film is used to produce photons from the point of ion impact. The photons emitted due to an ion impact are imaged on a position-sensitive detector to determine the location of a single event effect (SEE). Due to stringent resolution, intensity, wavelength, decay time, and radiation tolerance demands, an engineered material with very specific properties is required to act as the luminescent film. The requirements for this material are extensive. It must produce a high enough induced luminescent intensity so at least one photon is detected per ion hit. The emission wavelength must match the sensitivity of the detector used, and the luminescent decay time must be short enough to limit accidental coincidences. In addition, the material must be easy to handle and its luminescent properties must be tolerant to radiation damage. Materials studied for this application include plastic scintillators, GaN and GaN/InGaN quantum well structures, and lanthanide-activated ceramic phosphors. Results from characterization studies on these materials will be presented; including photoluminescence, cathodoluminescence, ion beam induced luminescence, luminescent decay times, and radiation damage. Results indicate that the ceramic phosphors are currently proving to be the ideal material for IPEM investigations.     

Developing a methodology for using case mix information

With the advent of DRG reimbursement for Medicare patients, hospitals have had to use their case mix data more effectively. This paper describes a method use to develop summary case mix reports using a spreadsheet program. With this approach, the hospital administration could interact more during the development of the summary reports. Once the summary reports are stabilized, they can be put into production on the Hospital's main frame computer.     

Integrating tester pin electronics

A 10-V pin electronics driver that can output signals with low distortion and fast risetimes for both narrow and wide voltage swings is described. The features combine to eliminate the need for dual drivers, pin cards, or test heads, which simplifies the testing of mixed-technology devices or modules. A high-voltages process module has been added to a standard 1.5-μm digital CMOS process, which allows the driver to be in the same silicon as the timing and formatting circuitry. Design and calibration techniques that overcome the limitations of the high-voltage CMOS process are examined     

Infective endocarditis as a complication of heroin use

Infective endocarditis in heroin addicts has been reported to have a mortality as high as 85% and reports have varied widely regarding predominant valvular involvement and infecting microorganisms. A retrspective study was done and 61 cases of heroin-associated infective endocarditis were identified at Freedmen's Hospital and the District of Columbia General Hospital, Washington, DC between January 1969 and January 1973. Our results indicate that staphylococcal infection of the tricuspid valve has a much higher incidence in this population than has generally been believed and that it is the predominant presentation of infective endocarditis in these patients. The outcome of patients in our series compares favorably with previous reports and suggests that early diagnosis and prompt institution of appropriate antimicrobial therapy are important and may lead to improved survival in addicts with tricuspid endocarditis.     

Children's spontaneous strategies for coping with pain: A review of the literature.

Reviews the literature on strategies children use for coping with pain before professional intervention. The development of direct methods of assessing children's behavioral and cognitive coping strategies is traced; and evidence for developmental differences in the types of strategies children employ is presented. Initial evidence regarding the effectiveness of spontaneous coping strategies is presented. Future research directions to be taken may include extension to pediatric chronic pain populations, outcome studies, and investigation of parents' roles in children's development and application of coping strategies. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Outlier removal in biomaterial image segmentations using a non-stationary Bayesian learning

Pattern Analysis and Applications - Segmentation of dried amnion biomaterial tends to produce invalid (outlier) contour point detections due to texture and colour inhomogeneity of the biomaterial....     

Electron tunneling through ultrathin boron nitride crystalline barriers

We investigate the electronic properties of ultrathin hexagonal boron nitride (h-BN) crystalline layers with different conducting materials (graphite, graphene, and gold) on either side of the barrier layer. The tunnel current depends exponentially on the number of h-BN atomic layers, down to a monolayer thickness. Conductive atomic force microscopy scans across h-BN terraces of different thickness reveal a high level of uniformity in the tunnel current. Our results demonstrate that atomically thin h-BN acts as a defect-free dielectric with a high breakdown field. It offers great potential for applications in tunnel devices and in field-effect transistors with a high carrier density in the conducting channel.     

The Ignorant Led by the Blind: A Hybrid Human–Machine Vision System for Fine-Grained Categorization

We present a visual recognition system for fine-grained visual categorization. The system is composed of a human and a machine working together and combines the complementary strengths of computer vision algorithms and (non-expert) human users. The human users provide two heterogeneous forms of information object part clicks and answers to multiple choice questions. The machine intelligently selects the most informative question to pose to the user in order to identify the object class as quickly as possible. By leveraging computer vision and analyzing the user responses, the overall amount of human effort required, measured in seconds, is minimized. Our formalism shows how to incorporate many different types of computer vision algorithms into a human-in-the-loop framework, including standard multiclass methods, part-based methods, and localized multiclass and attribute methods. We explore our ideas by building a field guide for bird identification. The experimental results demonstrate the strength of combining ignorant humans with poor-sighted machines the hybrid system achieves quick and accurate bird identification on a dataset containing 200 bird species.