Development of a polysilicon process based on chemical vapor deposition, phase 1

The development of a dichlorosilane-based reductive chemical vapor deposition process for the production of polycrystalline silicon is discussed. Experimental data indicate that the ease of ignition and explosion severity of dichlorosilane (DCS)/air mixtures is substantially attenuated if the DCS is diluted with hydrogen. Redesign of the process development unit to accommodate safety related information is described. Several different sources of trichlorosilane were used to generate a mixture of redistributed chlorosilanes via Dowex ion exchange resin. The unseparated mixtures were then fed to an experimental reactor in which silicon was deposited and the deposited silicon analyzed for electrically active impurities. At least one trichlorosilane source provided material of requisite purity. Silicon grown in the experimental reactor was converted to single crystal material and solar cells fabricated and tested

Application of Hapke photometric model to three geologic surfaces using PARABOLA bidirectional reflection data

The Geologic Remote Sensing Field Experiment (GRSFE) was conducted in July and September of 1989 to collect data with both ground and airborne instrumentation. A major objective of GRSFE was to collect data which could be used to test radiative transfer models for the extraction of composition and textural surface properties from remotely acquired data. Reported here are the initial results from an application of the Hapke photometric model, using data from the Portable Apparatus for Remote Acquisition of Bidirectional Observations of Land and Atmosphere (PARABOLA), a ground based radiometer with three spectral channels. PARABOLA data was collected in the Lunar Crater Volcanic Field in Nevada, specifically from the region of Lunar Lake, a playa. The Hapke model was found to be inadequate for three relatively common geologic surfaces (a clay-rich, hard packed surface with decimeter sized mudcracks; a cobble site, similar to a playa site, but strewn with basaltic cobbles and pebbles; and a surface mantled basalt lava flow). The model is not at fault; rather, the complexity of most geologic surfaces is not accounted for in the initial assumptions

BIRP: Software for interactive search and retrieval of image engineering data

Better Image Retrieval Programs (BIRP), a set of programs to interactively sort through and to display a database, such as engineering data for images acquired by spacecraft is described. An overview of the philosophy of BIRP design, the structure of BIRP data files, and examples that illustrate the capabilities of the software are provided

Image processing applied to gravity and topography data covering the continental United States

The applicability of fairly standard image processing techniques to processing and analyzing large geologic data sets in addressed. Image filtering techniques were used to interpolate between gravity station locations to produce a regularly spaced data array that preserves detail in areas with good coverage, and that produces a continuous tone image rather than a contour map. Standard image processing techniques were used to digitally register and overlay topographic and gravity data, and the data were displayed in ways that emphasize subtle but pervasive structural features. The potential of the methods is illustrated through a discussion of linear structures that appear in the processed data between the midcontinent gravity high and the Appalachians

When and How Shall I Plan Dental and Prosthetic Treatment for the Elderly?

The planning of dental and prosthetic treatment for the elderly requires knowledge of the patient’s oral and general health status as well as social orientation. As for most people, loss of teeth is associated with reduced quality of life. Thus, it must be of primary importance to prevent oral diseases leading to edentulism. However, due to medical, economic and social reasons, a conventional approach may not always be optimal. Scientific investigations and clinical experience confirm that treatment with implant-supported prosthesis is equally successful among the old as among younger patients. Good esthetics, chewing comfort and a minimum of future problems can be obtained by a treatment strategy based on timely intervention with implant-supported prosthesis

Live calcium imaging of Aedes aegypti neuronal tissues reveals differential importance of chemosensory systems for life-history-specific foraging strategies.

BackgroundThe mosquito Aedes aegypti has a wide variety of sensory pathways that have supported its success as a species as well as a highly competent vector of numerous debilitating infectious pathogens. Investigations into mosquito sensory systems and their effects on behavior are valuable resources for the advancement of mosquito control strategies. Numerous studies have elucidated key aspects of mosquito sensory systems, however there remains critical gaps within the field. In particular, compared to that of the adult form, there has been a lack of studies directed towards the immature life stages. Additionally, although numerous studies have pinpointed specific sensory receptors as well as responding motor outputs, there has been a lack of studies able to monitor both concurrently.ResultsTo begin filling aforementioned gaps, here we engineered Ae. aegypti to ubiquitously express a genetically encoded calcium indicator, GCaMP6s. Using this strain, combined with advanced microscopy, we simultaneously measured live stimulus-evoked calcium responses in both neuronal and muscle cells with a wide spatial range and resolution.ConclusionsBy coupling in vivo live calcium imaging with behavioral assays we were able to gain functional insights into how stimulus-evoked neural and muscle activities are represented, modulated, and transformed in mosquito larvae enabling us to elucidate mosquito sensorimotor properties important for life-history-specific foraging strategies

Long-term survivors of childhood cancer report quality of life and health status in parity with a comparison group

Background: There is a need for more knowledge about how survivors of childhood cancer perceive their lives and what influence current health status has on their quality of life. The purpose was to describe this among a group of long-term survivors and among a comparison group. Procedure: Telephone interviews were performed with a cohort of 246 long-term survivors and 296 randomly selected from the general population using the Schedule for the Evaluation of Individual Quality of Life- Direct Weighting (SEIQoL-DW). The participants nominated the areas they considered to be most important in life and rated the current status of each area on a seven-point category scale. An overall individual index score was calculated as a measure of quality of life. Self-reported health status was assessed using the Short Form Health Survey (SF-36). Results: Long-term survivors rated their overall quality of life and self-reported health status almost in parity with the comparison group. In both groups, family life, relations to other people, work and career, interests and leisure activities were the areas most frequently reported to influence quality of life. The survivors only differed from the comparison group on one of eight SF-36 scales reflecting problems with daily activities owing to physical health. Conclusions: Health status was not shown to have a major impact on overall quality of life, indicating that health and quality of life should be evaluated distinctively as different constructs. This should be taken in consideration in clinical care of children with childhood cancer and long-term survivors

Mojave remote sensing field experiment

The Mojave Remote Sensing Field Experiment (MFE), conducted in June 1988, involved acquisition of Thermal Infrared Multispectral Scanner (TIMS); C, L, and P-band polarimetric radar (AIRSAR) data; and simultaneous field observations at the Pisgah and Cima volcanic fields, and Lavic and Silver Lake Playas, Mojave Desert, California. A LANDSAT Thematic Mapper (TM) scene is also included in the MFE archive. TM-based reflectance and TIMS-based emissivity surface spectra were extracted for selected surfaces. Radiative transfer procedures were used to model the atmosphere and surface simultaneously, with the constraint that the spectra must be consistent with field-based spectral observations. AIRSAR data were calibrated to backscatter cross sections using corner reflectors deployed at target sites. Analyses of MFE data focus on extraction of reflectance, emissivity, and cross section for lava flows of various ages and degradation states. Results have relevance for the evolution of volcanic plains on Venus and Mars

Opportunity Microscopic Imager Results from the Western Rim of Endeavour Crater

The Athena science payload on the Mars Exploration Rovers (MER Spirit and Opportunity) includes the Microscopic Imager (MI), a fixed focus close-up camera mounted on the instrument arm. The MI acquires images at a scale of 31 micrometers/pixel over a broad spectral range (400 to 700 nm) using only natural illumination of target surfaces. Radio signals from Spirit have not been received since March 2010, so attempts to communicate with that rover ceased in mid-2011. The Opportunity MI optics were contaminated by a global dust storm in 2007. That contamination continues to reduce the contrast of MI images, and is being monitored by occasionally imaging the sky

Structure of the midcontinent basement. Topography, gravity, seismic, and remote sensing

Some 600,000 discrete Bouguer gravity estimates of the continental United States were spatially filtered to produce a continuous tone image. The filtered data were also digitally painted in color coded form onto a shaded relief map. The resultant image is a colored shaded relief map where the hue and saturation of a given image element is controlled by the value of the Bouguer anomaly. Major structural features (e.g., midcontinent gravity high) are readily discernible in these data, as are a number of subtle and previously unrecognized features. A linear gravity low that is approximately 120 to 150 km wide extends from southeastern Nebraska, at a break in the midcontinent gravity high, through the Ozark Plateau, and across the Mississippi embayment. The low is also aligned with the Lewis and Clark lineament (Montana to Washington), forming a linear feature of approximately 2800 km in length. In southeastern Missouri the gravity low has an amplitude of 30 milligals, a value that is too high to be explained by simple valley fill by sedimentary rocks