Science.gov

Sample records for liss core study

  1. Comparison of LSS-IV and LISS-III+LISS-IV merged data for classification of crops

    NASA Astrophysics Data System (ADS)

    Hebbar, R.; Sesha Sai, M. V. R.

    2014-11-01

    Resourcesat-1 satellite with its unique capability of simultaneous acquisition of multispectral images at different spatial resolutions (AWiFS, LISS-III and LISS-IV MX / Mono) has immense potential for crop inventory. The present study was carried for selection of suitable LISS-IV MX band for data fusion and its evaluation for delineation different crops in a multi-cropped area. Image fusion techniques namely intensity hue saturation (IHS), principal component analysis (PCA), brovey, high pass filter (HPF) and wavelet methods were used for merging LISS-III and LISS-IV Mono data. The merged products were evaluated visually and through universal image quality index, ERGAS and classification accuracy. The study revealed that red band of LISS-IV MX data was found to be optimal band for merging with LISS-III data in terms of maintaining both spectral and spatial information and thus, closely matching with multispectral LISS-IVMX data. Among the five data fusion techniques, wavelet method was found to be superior in retaining image quality and higher classification accuracy compared to commonly used methods of IHS, PCA and Brovey. The study indicated that LISS-IV data in mono mode with wider swath of 70 km could be exploited in place of 24km LISS-IVMX data by selection of appropriate fusion techniques by acquiring monochromatic data in the red band.

  2. LISS-4 camera for Resourcesat

    NASA Astrophysics Data System (ADS)

    Paul, Sandip; Dave, Himanshu; Dewan, Chirag; Kumar, Pradeep; Sansowa, Satwinder Singh; Dave, Amit; Sharma, B. N.; Verma, Anurag

    2006-12-01

    The Indian Remote Sensing Satellites use indigenously developed high resolution cameras for generating data related to vegetation, landform /geomorphic and geological boundaries. This data from this camera is used for working out maps at 1:12500 scale for national level policy development for town planning, vegetation etc. The LISS-4 Camera was launched onboard Resourcesat-1 satellite by ISRO in 2003. LISS-4 is a high-resolution multi-spectral camera with three spectral bands and having a resolution of 5.8m and swath of 23Km from 817 Km altitude. The panchromatic mode provides a swath of 70Km and 5-day revisit. This paper briefly discusses the configuration of LISS-4 Camera of Resourcesat-1, its onboard performance and also the changes in the Camera being developed for Resourcesat-2. LISS-4 camera images the earth in push-broom mode. It is designed around a three mirror un-obscured telescope, three linear 12-K CCDs and associated electronics for each band. Three spectral bands are realized by splitting the focal plane in along track direction using an isosceles prism. High-speed Camera Electronics is designed for each detector with 12- bit digitization and digital double sampling of video. Seven bit data selected from 10 MSBs data by Telecommand is transmitted. The total dynamic range of the sensor covers up to 100% albedo. The camera structure has heritage of IRS- 1C/D. The optical elements are precisely glued to specially designed flexure mounts. The camera is assembled onto a rotating deck on spacecraft to facilitate +/- 26° steering in Pitch-Yaw plane. The camera is held on spacecraft in a stowed condition before deployment. The excellent imageries from LISS-4 Camera onboard Resourcesat-1 are routinely used worldwide. Such second Camera is being developed for Resourcesat-2 launch in 2007 with similar performance. The Camera electronics is optimized and miniaturized. The size and weight are reduced to one third and the power to half of the values in Resourcesat

  3. Rain-induced subsurface airflow and Lisse effect

    USGS Publications Warehouse

    Guo, H.; Jiao, J.J.; Weeks, E.P.

    2008-01-01

    Water-level increase after rainfall is usually indicative of rainfall recharge to groundwater. This, however, may not be true if the Lisse effect occurs. This effect represents the water-level increase in a well driven by airflow induced by an advancing wetting front during highly intensive rains. The rainwater, which may behave like a low-permeability lid, seals the ground surface so that the air pressure beneath the wetting front is increased because of air compression due to downward movement of the wetting front. A rapid and substantial rise of the water level in the well screened below water table, which bears no relationship to groundwater recharge, can be induced when various factors such as soil properties and the rain-runoff condition combine favorably. A transient, three-dimensional and variably saturated flow model was employed to study the air and groundwater flows in the soil under rain conditions. The objectives of this paper are two-fold: to evaluate the reliability of the theory of the Lisse effect presented by Weeks to predict its magnitude in modeled situations that mimic the physical complexity of real aquifers, and to conduct parametric studies on the sensitivity of the water-level rise in the well to soil properties and the rain event. The simulation results reveal that the magnitude of the Lisse effect increases with the ponding depth. Soil permeability plays a key role in generating the Lisse effect. The water-level rise in the well is delayed relative to the air-pressure rise in the unsaturated zone when the soil permeability is low, and the maximum water-level rise is less than the maximum air pressure induced by rain infiltration. The simulation also explores the sensitivity of the Lisse effect to the van Genuchten parameters and the water table depth. Copyright 2008 by the American Geophysical Union.

  4. Investigating the Capability of IRS-P6-LISS IV Satellite Image for Pistachio Forests Density Mapping (case Study: Northeast of Iran)

    NASA Astrophysics Data System (ADS)

    Hoseini, F.; Darvishsefat, A. A.; Zargham, N.

    2012-07-01

    In order to investigate the capability of satellite images for Pistachio forests density mapping, IRS-P6-LISS IV data were analyzed in an area of 500 ha in Iran. After geometric correction, suitable training areas were determined based on fieldwork. Suitable spectral transformations like NDVI, PVI and PCA were performed. A ground truth map included of 34 plots (each plot 1 ha) were prepared. Hard and soft supervised classifications were performed with 5 density classes (0-5%, 5-10%, 10-15%, 15-20% and > 20%). Because of low separability of classes, some classes were merged and classifications were repeated with 3 classes. Finally, the highest overall accuracy and kappa coefficient of 70% and 0.44, respectively, were obtained with three classes (0-5%, 5-20%, and > 20%) by fuzzy classifier. Considering the low kappa value obtained, it could be concluded that the result of the classification was not desirable. Therefore, this approach is not appropriate for operational mapping of these valuable Pistachio forests.

  5. Automated co-registration of images from multiple bands of Liss-4 camera

    NASA Astrophysics Data System (ADS)

    Radhadevi, P. V.; Solanki, S. S.; Jyothi, M. V.; Nagasubramanian, V.; Varadan, Geeta

    Three multi-spectral bands of the Liss-4 camera of IRS-P6 satellite are physically separated in the focal plane in the along-track direction. The time separation of 2.1 s between the acquisition of first and last bands causes scan lines acquired by different bands to lie along different lines on the ground which are not parallel. Therefore, the raw images of multi-spectral bands need to be registered prior to any simple application like data visualization. This paper describes a method for co-registration of multiple bands of Liss-4 camera through photogrammetric means using the collinearity equations. A trajectory fit using the given ephemeris and attitude data, followed by direct georeferencing is being employed in this model. It is also augmented with a public domain DEM for the terrain dependent input to the model. Finer offsets after the application of this parametric technique are addressed by matching a small subsection of the bands (100×100 pixels) using an image-based method. Resampling is done by going back to original raw data when creating the product after refining image coordinates with the offsets. Two types of aligned products are defined in this paper and their operational flow is described. Datasets covering different types of terrain and also viewed with different geometries are studied with extensive number of points. The band-to-band registration (BBR) accuracies are reported. The algorithm described in this paper for co-registration of Liss-4 bands is an integral part of the software package Value Added Products generation System (VAPS) for operational generation of IRS-P6 data products.

  6. Classification of Liss IV Imagery Using Decision Tree Methods

    NASA Astrophysics Data System (ADS)

    Verma, Amit Kumar; Garg, P. K.; Prasad, K. S. Hari; Dadhwal, V. K.

    2016-06-01

    Image classification is a compulsory step in any remote sensing research. Classification uses the spectral information represented by the digital numbers in one or more spectral bands and attempts to classify each individual pixel based on this spectral information. Crop classification is the main concern of remote sensing applications for developing sustainable agriculture system. Vegetation indices computed from satellite images gives a good indication of the presence of vegetation. It is an indicator that describes the greenness, density and health of vegetation. Texture is also an important characteristics which is used to identifying objects or region of interest is an image. This paper illustrate the use of decision tree method to classify the land in to crop land and non-crop land and to classify different crops. In this paper we evaluate the possibility of crop classification using an integrated approach methods based on texture property with different vegetation indices for single date LISS IV sensor 5.8 meter high spatial resolution data. Eleven vegetation indices (NDVI, DVI, GEMI, GNDVI, MSAVI2, NDWI, NG, NR, NNIR, OSAVI and VI green) has been generated using green, red and NIR band and then image is classified using decision tree method. The other approach is used integration of texture feature (mean, variance, kurtosis and skewness) with these vegetation indices. A comparison has been done between these two methods. The results indicate that inclusion of textural feature with vegetation indices can be effectively implemented to produce classifiedmaps with 8.33% higher accuracy for Indian satellite IRS-P6, LISS IV sensor images.

  7. The Core Journal Concept in Black Studies

    ERIC Educational Resources Information Center

    Weissinger, Thomas

    2010-01-01

    Black Studies scholars have shown interest in the core journal concept. Indeed, the idea of core journals for the study of the Black experience has changed several times since 1940. While Black Studies scholars are citing Black Studies journals with frequency, they also cite traditional disciplinary journals a great deal of the time. However,…

  8. Pre-flight radiometric and spectral calibration of Resourcesat-2A-LISS3* payload

    NASA Astrophysics Data System (ADS)

    Seth, Harish; Detroja, M. P.; Padmanabhan, Deepa; Raj, Vedant; Kumar, Anil; Sarkar, S. S.

    2016-05-01

    Resourcesat-2A is a follow-on mission of Resourcesat-2, belongs to Indian Remote Sensing Program. It is expected to be launched in 2016 and is dedicated mainly to agricultural applications. One of the payloads, LISS3* is a medium resolution (23.5 m) sensor having four multispectral bands from 450 to 1650 nm. These spectral bands are named as B2 (550 nm), B3 (650 nm), B4 (815 nm) and B5 (1625 nm) respectively covering Visible, Near Infrared (NIR) and Short Wave Infrared (SWIR) regions. In order to provide quality data to the user community for long term scientific applications pre-flight ground calibration is carried out. This paper describes pre-flight spectral and radiometric calibration of LISS3* payload and its performance evaluation. Since it is a continuity mission to Resourcesat-2, which was launched in April 2011 so for generating long-term data record and correlation with previous observations, its parameters are compared with Resourcesat-2 LISS3* payload. The main spectral parameters like central wavelength, and pass band is determined using system level spectral response and compared for both the mission and differences are outlined. The next important exercise is pre-flight radiometric calibration, which was carried out in laboratory using a standard integrating sphere traceable to NIST standards. This paper highlights the technique adopted during pre-flight calibration of the radiometric response and performance assessment of all 4 bands of LISS3* in terms of major electro-optical parameters like Signal to Noise Ratio (SNR), Saturation Radiance (SR) etc. The observed SR shows that the sensor can measure spectral radiance from Earth up to 100% albedo.

  9. Infrared and Submilllimeter Studies of Dense Cores

    NASA Astrophysics Data System (ADS)

    Bourke, Tyler L.

    2014-07-01

    Dense Cores are the birthplace of stars, and so understanding their structure and evolution is key to understanding star formation. Information on the density, temperature, and motions within cores are needed to describe these properties, and are obtained through continuum and line observations at far infrared and submm/mm wavelengths. Recent observations of dust emission with Herschel and molecular line observations with single-dish telescopes and interferometers provide the wavelength coverage and resolution to finally map core properties without appealing to spherical simplifications. Although large scale Herschel observations reveal numerous filaments in molecular clouds which are well described by cylindrical geometries, cores are still modeled as spherical entities. A few examples of other core geometries exist in the literature, and the wealth of new data on cloud filaments demand that non-spherical models receive more attention in future studies. This talk will examine the evidence for non-spherical cores and their connection to the filaments from which they form.

  10. Improving classification accuracy using multi-date IRS/LISS data and development of thermal stress index for Asiatic lion habitat

    NASA Astrophysics Data System (ADS)

    Gupta, Rajendra Kumar

    The increase in lion and leopard population in the GIR wild life sanctuary and National Park (Gir Protected Area) demands periodic and precision monitoring of habitat at close intervals using space based remote sensing data. Besides characterizing the different forest classes, remote sensing needs to support for the assessment of thermal stress zones and identification of possible corridors for lion dispersion to new home ranges. The study focuses on assessing the thematic forest classification accuracies in percentage terms(CA) attainable using single date post-monsoon (CA=60, kappa = 0.514) as well as leaf shedding (CA=48.4, kappa = 0.372) season data in visible and Near-IR spectral bands of IRS/LISS-III at 23.5 m spatial resolution; and improvement of CA by using joint two date (multi-temporal) data sets (CA=87.2, kappa = 0.843) in the classification. The 188 m spatial resolution IRS/WiFS and 23.5 m spatial resolution LISS-III data were used to study the possible corridors for dispersion of Lions from GIR protected areas (PA). A relative thermal stress index (RTSI) for Gir PA has been developed using NOAA/ AVHRR data sets of post-monsoon, leaf shedded and summer seasons. The paper discusses the role of RTSI as a tool to work out forest management plans using leaf shedded season data to combat the thermal stress in the habitat, by identifying locations for artificial water holes during the ensuing summer season.

  11. Assessment of water quality parameters of the Harike wetland in India, a Ramsar site, using IRS LISS IV satellite data.

    PubMed

    Mabwoga, Samson Okongo; Chawla, Amit; Thukral, Ashwani Kumar

    2010-11-01

    This study aims at the classification and water quality assessment of Harike wetland (Ramsar site) in India using satellite images from the Indian Remote Sensing satellite, Resourcesat (IRS P6). The Harike wetland is a converging zone of two rivers, Beas and Sutlej. The satellite images of IRS Linear Imaging Self Scanner (LISS) IV multispectral sensor with three bands (green, red, and near infrared (NIR)) and a spatial resolution of 5.8 m were classified using supervised image classification techniques. Field points for image classification and water sampling were recorded using a Garmin eTrex Global Positioning System. The water quality parameters assessed were dissolved oxygen, conductivity, pH, turbidity, total and suspended solids (SS), chemical oxygen demand, and Secchi disk transparency (SDT). Correlations were established between turbidity and SS, SS and SDT, and total solids and turbidity. Using reflectance values from the green, red, and NIR bands, we then plotted the water quality parameters with the mean digital number values from the satellite imagery. The NIR band correlated significantly with the water quality parameters, whereas, using SDT values, it was observed that the green and the red reflectance bands were able to distinguish the waters from the two rivers, which have different water qualities. PMID:19882220

  12. Automated Registration of Images from Multiple Bands of Resourcesat-2 Liss-4 camera

    NASA Astrophysics Data System (ADS)

    Radhadevi, P. V.; Solanki, S. S.; Jyothi, M. V.; Varadan, G.

    2014-11-01

    Continuous and automated co-registration and geo-tagging of images from multiple bands of Liss-4 camera is one of the interesting challenges of Resourcesat-2 data processing. Three arrays of the Liss-4 camera are physically separated in the focal plane in alongtrack direction. Thus, same line on the ground will be imaged by extreme bands with a time interval of as much as 2.1 seconds. During this time, the satellite would have covered a distance of about 14 km on the ground and the earth would have rotated through an angle of 30". A yaw steering is done to compensate the earth rotation effects, thus ensuring a first level registration between the bands. But this will not do a perfect co-registration because of the attitude fluctuations, satellite movement, terrain topography, PSM steering and small variations in the angular placement of the CCD lines (from the pre-launch values) in the focal plane. This paper describes an algorithm based on the viewing geometry of the satellite to do an automatic band to band registration of Liss-4 MX image of Resourcesat-2 in Level 1A. The algorithm is using the principles of photogrammetric collinearity equations. The model employs an orbit trajectory and attitude fitting with polynomials. Then, a direct geo-referencing with a global DEM with which every pixel in the middle band is mapped to a particular position on the surface of the earth with the given attitude. Attitude is estimated by interpolating measurement data obtained from star sensors and gyros, which are sampled at low frequency. When the sampling rate of attitude information is low compared to the frequency of jitter or micro-vibration, images processed by geometric correction suffer from distortion. Therefore, a set of conjugate points are identified between the bands to perform a relative attitude error estimation and correction which will ensure the internal accuracy and co-registration of bands. Accurate calculation of the exterior orientation parameters with

  13. Monitoring Environment with GIS for Part of Thiruvallur Town Using Cartosat 1 Stereo, Pan & Resourcesat Liss 4 MSS Merged Data

    NASA Astrophysics Data System (ADS)

    Mohamed, G. S.; Venkatchalam, R. V.; Ramamurthhy, M.; Gummidipoondi, R. J.; Ramillah, M.

    2012-07-01

    Thiruvallur town is about 44 km from Chennai in Tamil nadu state of India with a population of 130000 , covering 10.75 sq km area. It is about 2km from Sri Venkateswara College of Engineering and Technology. It was Taluk (Sub Division'.s) head quarters and from 1991 it was upgraded as District head quarters after the formation of Thiruvallur District. With rapid growth of town the Population density of Thiruvallur has increased in the past three decades from 300 persons/sq.km in 1951, to 6000 persons/sq.km in 1981 and now it is 12925 persons/sq.km in 2011. The creation of District administrative collector office, headquarters offices for police, judicial courts and Tamil Nadu and Federal Government development department's offices, establishment of multinationals major industries like Caterpillar, Kingfishers,Hindustan Motors, Mahendra Automobiles, Coco cola, Japanese Glass industry, Korean LOTO etc apart from mushrooming growth of about 41 Engineering, Nursing, Education, Medical, Naval, Arts and Science colleges, International Public schools,Governmentt, Private schools and Polytechnics added to the population of this Town. It is well connected by National Highways and Railways and upgraded as District Municipality. This resulted in urban drainage problem and conversion of Agriculture land and lakes for housing, establishment of major Govt and Private Hospitals including special units for Eye care, Cardiology, and Health Clinics, pharmacies etc. The effect of urbanization on environment of this once silent rural temple town which was supporting intensive agriculture activities , green with paddy fields is studied with high resolution satellite data is know the impact on health and environment changes from 2008 to 2011, using 2.5m resolution PAN stereo data of Cartosat 1 merged with 5.8 m resolution Multi Spectral data of LISS 4 of Resourcesat 1 of Indian Remote sensing satellites and Geo Eye satellite image of 2011 from Google Earth web site for the western part

  14. Cardiovascular Deconditioning in Humans: Human Studies Core

    NASA Technical Reports Server (NTRS)

    Williams, Gordon

    1999-01-01

    Major cardiovascular problems, secondary to cardiovascular deconditioning, may occur on extended space missions. While it is generally assumed that the microgravity state is the primary cause of cardiovascular deconditioning, sleep deprivation and disruption of diurnal rhythms may also play an important role. Factors that could be modified by either or both of these perturbations include: autonomic function and short-term cardiovascular reflexes, vasoreactivity, circadian rhythm of cardiovascular hormones (specifically the renin-angiotensin system) and renal sodium handling and hormonal influences on that process, venous compliance, cardiac mass, and cardiac conduction processes. The purpose of the Human Studies Core is to provide the infrastructure to conduct human experiments which will allow for the assessment of the likely role of such factors in the space travel associated cardiovascular deconditioning process and to develop appropriate countermeasures. The Core takes advantage of a newly-created Intensive Physiologic Monitoring (IPM) Unit at the Brigham and Women's Hospital, Boston, MA, to perform these studies. The Core includes two general experimental protocols. The first protocol involves a head down tilt bed-rest study to simulate microgravity. The second protocol includes the addition of a disruption of circadian rhythms to the simulated microgravity environment. Before and after each of these environmental manipulations, the subjects will undergo acute stressors simulating changes in volume and/or stress, which could occur in space and on return to Earth. The subjects are maintained in a rigidly controlled environment with fixed light/dark cycles, activity pattern, and dietary intake of nutrients, fluids, ions and calories.

  15. Magnetic core studies at LBNL and LLNL

    SciTech Connect

    Molvik, A.W.; Faltens, A.; Reginato, L.; Blaszkiewicz, M.; Smith, C.; Wood, R.

    1997-09-20

    The objective of this work is to minimize the cost of the materials and maximize the performance of magnetic cores, a major cost component of a Heavy-Ion-Fusion, HIF, induction accelerator driver. This includes selection of the alloy for cost and performance, and maximizing the performance of each alloy evaluated. The two major performance parameters are the magnetic flux swing and the energy loss. The volt seconds of the cores, obtained from the flux swing with Faraday's Law, determines the beam energy and duration. Core losses from forming domains and moving their boundaries are a major factor in determining the efficiency of an induction accelerator.

  16. Preserving Social Studies as Core Curricula in an Era of Common Core Reform

    ERIC Educational Resources Information Center

    Denton, David W.; Sink, Cindy

    2015-01-01

    Education reform over the last two decades has changed perceptions of core curricula. Although social studies has traditionally been part of the core, emphasis on standards-based teaching and learning, along with elaborate accountability schemes, is causing unbalanced treatment of subjects. While the research literature indicates teachers are…

  17. Idaho NTE Core Battery Validation: Study Report.

    ERIC Educational Resources Information Center

    Zetler, Alan G.

    The content validity of the National Teacher Examinations (NTE) Core Battery tests of communications skills, general knowledge, and professional knowledge was examined to determine whether this commercially available test was suitable for initial teacher certification in Idaho. Focus was on recommending adoption scores (cut scores) to the State…

  18. Marketing Competencies: A Core Course of Study.

    ERIC Educational Resources Information Center

    Cicchetti, Elric A.

    The document provides a systematic analysis of curriculum in marketing, focusing on the design and evaluation of a vocational course in the distributive education curriculum. The core course, entitled basic marketing, was selected because marketing competencies are essential to every distributive education student. The following areas are…

  19. Mercury's Core Molten, Radar Study Shows

    NASA Astrophysics Data System (ADS)

    2007-05-01

    Scientists using a high-precision planetary radar technique for the first time have discovered that the innermost planet Mercury probably has a molten core, resolving a mystery of more than three decades. The discovery, which used the National Science Foundation's Robert C. Byrd Green Bank Telescope in West Virginia and Arecibo Observatory in Puerto Rico, and NASA/Jet Propulsion Laboratory antennas in California, is an important step toward a better understanding of how planets form and evolve. Planetary Radar High-precision planetary radar technique sent signal to Mercury, received reflection. CREDIT: Bill Saxton, NRAO/AUI/NSF Click on image for high-resolution file (447 KB) "For a long time it was thought we'd have to land spacecraft on Mercury to learn if its core is solid or molten. Now we've answered that question using ground-based telescopes," said Jean-Luc Margot, of Cornell University, leader of the research team, which published its results in the May 4 issue of the journal Science. Mercury is one of the least-understood of the planets in our Solar System. Its distance from the Sun is just over one-third that of the Earth, and it contains a mass just 5½ percent that of Earth. Only about half of Mercury's surface has been photographed by a spacecraft, Mariner 10, back in 1974. Mariner 10 also discovered that Mercury has a weak magnetic field, about one percent as strong as Earth's. That discovery spurred a scientific debate about the planet's core. Scientists normally expect a rocky planet's magnetic field to be caused by an electromagnetic dynamo in a molten core. However, Mercury is so small that most scientists expected its core to have cooled and solidified long ago. Those scientists speculated that the magnetic field seen today may have been "frozen" into the planet when the core cooled. "Whether the core is molten or solid today depends greatly on the chemical composition of the core. That chemical composition can provide important clues about the

  20. LONG ISLAND SOUND STUDY 2002 CCMP IR

    EPA Science Inventory

    The Long Island Sound Study Implementation Review (IR) summarizes the progress and challenges ahead for the for the Long Island Sound Study (LISS) through examination of it activities in relation to the CCMP. The LISS CCMP identified six major areas requiring management action: 1...

  1. Graduate Study in Advertising and the Core Curriculum.

    ERIC Educational Resources Information Center

    Applegate, Edd

    1995-01-01

    Discusses business school guidelines and journalism school guidelines for graduate education. Discusses graduate study in advertising and the advertising core. Outlines suggested changes to the advertising core to make it more attractive to advertising agency executives and to meet the challenges of the future. (SR)

  2. Ferromagnetic resonance studies of lunar core stratigraphy

    NASA Technical Reports Server (NTRS)

    Housley, R. M.; Cirlin, E. H.; Goldberg, I. B.; Crowe, H.

    1976-01-01

    We first review the evidence which links the characteristic ferromagnetic resonance observed in lunar fines samples with agglutinatic glass produced primarily by micrometeorite impacts and present new results on Apollo 15, 16, and 17 breccias which support this link by showing that only regolith breccias contribute significantly to the characteristic FMR intensity. We then provide a calibration of the amount of Fe metal in the form of uniformly magnetized spheres required to give our observed FMR intensities and discuss the theoretical magnetic behavior to be expected of Fe spheres as a function of size. Finally, we present FMR results on samples from every 5 mm interval in the core segments 60003, 60009, and 70009. These results lead us to suggest: (1) that secondary mixing may generally be extensive during regolith deposition so that buried regolith surfaces are hard to recognize or define; and (2) that local grinding of rocks and pebbles during deposition may lead to short scale fluctuations in grain size, composition, and apparent exposure age of samples.

  3. Core compressor exit stage study, 2

    NASA Technical Reports Server (NTRS)

    Behlke, R. F.; Burdsall, E. A.; Canal, E., Jr.; Korn, N. D.

    1979-01-01

    A total of two three-stage compressors were designed and tested to determine the effects of aspect ratio on compressor performance. The first compressor was designed with an aspect ratio of 0.81; the other, with an aspect ratio of 1.22. Both compressors had a hub-tip ratio of 0.915, representative of the rear stages of a core compressor, and both were designed to achieve a 15.0% surge margin at design pressure ratios of 1.357 and 1.324, respectively, at a mean wheel speed of 167 m/sec. At design speed the 0.81 aspect ratio compressor achieved a pressure ratio of 1.346 at a corrected flow of 4.28 kg/sec and an adiabatic efficiency of 86.1%. The 1.22 aspect ratio design achieved a pressure ratio of 1.314 at 4.35 kg/sec flow and 87.0% adiabatic efficiency. Surge margin to peak efficiency was 24.0% with the lower aspect ratio blading, compared with 12.4% with the higher aspect ratio blading.

  4. Pre-conceptual design study of ASTRID core

    SciTech Connect

    Varaine, F.; Marsault, P.; Chenaud, M. S.; Bernardin, B.; Conti, A.; Sciora, P.; Venard, C.; Fontaine, B.; Devictor, N.; Martin, L.; Scholer, A. C.; Verrier, D.

    2012-07-01

    In the framework of the ASTRID project at CEA, core design studies are performed at CEA with the AREVA and EDF support. At the stage of the project, pre-conceptual design studies are conducted in accordance with GEN IV reactors criteria, in particularly for safety improvements. An improved safety for a sodium cooled reactor requires revisiting many aspects of the design and is a rather lengthy process in current design approach. Two types of cores are under evaluation, one classical derived from the SFR V2B and one more challenging called CFV (low void effect core) with a large gain on the sodium void effect. The SFR V2b core have the following specifications: a very low burn-up reactivity swing (due to a small cycle reactivity loss) and a reduced sodium void effect with regard to past designs such as the EFR (around 2$ minus). Its performances are an average burn-up of 100 GWd/t, and an internal conversion ratio equal to one given a very good behavior of this core during a control rod withdrawal transient). The CFV with its specific design offers a negative sodium void worth while maintaining core performances. In accordance of ASTRID needs for demonstration those cores are 1500 MWth power (600 MWe). This paper will focus on the CFV pre-conceptual design of the core and S/A, and the performances in terms of safety will be evaluated on different transient scenario like ULOF, in order to assess its intrinsic behavior compared to a more classical design like V2B core. The gap in term of margin to a severe accident due to a loss of flow initiator underlines the potential capability of this type of core to enhance prevention of severe accident in accordance to safety demonstration. (authors)

  5. Feasibility study of full-reactor gas core demonstration test

    NASA Technical Reports Server (NTRS)

    Kunze, J. F.; Lofthouse, J. H.; Shaffer, C. J.; Macbeth, P. J.

    1973-01-01

    Separate studies of nuclear criticality, flow patterns, and thermodynamics for the gas core reactor concept have all given positive indications of its feasibility. However, before serious design for a full scale gas core application can be made, feasibility must be shown for operation with full interaction of the nuclear, thermal, and hydraulic effects. A minimum sized, and hence minimum expense, test arrangement is considered for a full gas core configuration. It is shown that the hydrogen coolant scattering effects dominate the nuclear considerations at elevated temperatures. A cavity diameter of somewhat larger than 4 ft (122 cm) will be needed if temperatures high enough to vaporize uranium are to be achieved.

  6. Thermal-hydraulic studies on molten core-concrete interactions

    SciTech Connect

    Greene, G.A.

    1986-10-01

    This report discusses studies carried out in connection with light water power reactor accidents. Recent assessments have indicated that the consequences of molten-core concrete interactions dominate the considerations of severe accidents. The two areas of interest that have been investigated are interlayer heat and mass transfer and liquid-liquid boiling. Interlayer heat and mass transfer refers to processes that occur within a core melt between the stratified, immiscible phases of core oxides and metals. Liquid-liquid boiling refers to processes that occur at the melt-concrete on melt-coolant interface. (JDH)

  7. Genomic and Proteomic Studies on Plesiomonas shigelloides Lipopolysaccharide Core Biosynthesis

    PubMed Central

    Aquilini, Eleonora; Merino, Susana; Regué, Miguel

    2014-01-01

    We report here the identification of waa clusters with the genes required for the biosynthesis of the core lipopolysaccharides (LPS) of two Plesiomonas shigelloides strains. Both P. shigelloides waa clusters shared all of the genes besides the ones flanking waaL. In both strains, all of the genes were found in the waa gene cluster, although one common core biosynthetic gene (wapG) was found in a different chromosome location outside the cluster. Since P. shigelloides and Klebsiella pneumoniae share a core LPS carbohydrate backbone extending up at least to the second outer-core residue, the functions of the common P. shigelloides genes were elucidated by genetic complementation studies using well-defined K. pneumoniae mutants. The function of strain-specific inner- or outer-core genes was identified by using as a surrogate acceptor LPS from three well-defined K. pneumoniae core LPS mutants. Using this strategy, we were able to assign a proteomic function to all of the P. shigelloides waa genes identified in the two strains encoding six new glycosyltransferases (WapA, -B, -C, -D, -F, and -G). P. shigelloides demonstrated an important variety of core LPS structures, despite being a single species of the genus, as well as high homologous recombination in housekeeping genes. PMID:24244003

  8. Evaluation of Catrosat 1PAN Stereo and Resourcesat Liss 4 MSS Merged Data for Morphometric Analysis, Delineation of Drainage Basins and Codification in Tamil Nadu, India and Australia

    NASA Astrophysics Data System (ADS)

    Mohamed, G. S.; Srinivasan, S.; Pandian, R.; Gummidipoondi, R. J.; Venkatchalam, R. V.; Swaminathan. S, S.

    2012-07-01

    The Topographic maps and Aerial Photographs are used for morphometric analysis of drainage basins and mapping contours with drainage. The stereo pairs of 2.5 m resolution Cartosat 1, Indian satellite 2 and merged data with 5.5 m resolution P6 Resourcesat 1 LISS 4 Indian satellite of 2001 is used to map, rills, gullies, and streams of first order to evaluate part of drainage basin of Cooum and Poondi Reservoir in Thiruvallur taluk of Tamil Nadu state. The Geo Eye latest 2011data is also used with Catrosat 1Stereo data to study present morphology of tiny micro watersheds to study the use of High resolution data for delineation and codification of watersheds. This study area is in an inter fluvial drainage basin of Cooum and Kusasthalai rivers. Kusasthalai river drains in Poondi reservoir which is about 50 km from Chennai. The excess water from Kosasthalai is also diverted through Kesawaram weir to Cooum river which passes through Thiruvallur and Chennai city before it's confluence with Bay of Benegal in the east. As Cooum basin is at higher elevation, water for irrigation is again diverted through chain of tanks to Kusasthalai river basin to drain in Poondi reservoir. Delineation of water sheds in this fluvial basin is difficult by manual survey as man made irrigation channels, natural drainage streams etc., have to be clearly identified. The streams of various orders are identified based on Strahler stream order hierarchy of tributaries, slops and contours using large scale satellite data. The micro water sheds are delinated identifying the ridges from Catrosat data for this interfluves basin which has mild slop. To illustrate this research, parts of two micro watersheds which were delineated using 1:50000 data for Tamil Nadu watershed Atlas up to 7th order streams are taken up for a detailed study using high resolution data. 19 Micro watersheds with streams up to 10th order are mapped. The capability of high resolution satellite data for digital as well as visual

  9. Implications of Common Core State Standards on the Social Studies

    ERIC Educational Resources Information Center

    Kenna, Joshua L.; Russell, William B., III.

    2014-01-01

    Social studies teachers have often been on the outside looking in during much of the era billed as the standards-based educational reform (SBER), but with the adoption and implementation of the Common Core State Standards (CCSS), social studies teachers seem to have been invited back inside. Yet, how will the standards impact social studies…

  10. Core design studies for advanced burner test reactor.

    SciTech Connect

    Yang, W. S.; Kim, T. K.; Hill, R. N.; Nuclear Engineering Division

    2008-01-01

    The U.S. government announced in February 2006 the Global Nuclear Energy Partnership (GNEP) to expand the use of nuclear energy to meet increasing global energy demand, to address nuclear waste management concerns and to promote non-proliferation. The advanced burner reactor (ABR) based on a fast spectrum is one of the three major technologies to be demonstrated in GNEP. In FY06, a pre-conceptual design study was performed to develop an advanced burner test reactor (ABTR) that supports development of a prototype full-scale ABR, which would be followed by commercial deployment of ABRs. The primary objectives of the ABTR were (1) to demonstrate reactor-based transmutation of transuranics (TRU) as part of an advanced fuel cycle, (2) to qualify the TRU-containing fuels and advanced structural materials needed for a full-scale ABR, (3) to support the research, development and demonstration required for certification of an ABR standard design by the U.S. Nuclear Regulatory Commission. Based on these objectives, core design and fuel cycle studies were performed to develop ABTR core designs, which can accommodate the expected changes of the TRU feed and the conversion ratio. Various option and trade-off studies were performed to determine the appropriate power level and conversion ratio. Both ternary metal alloy (U-TRU-10Zr) and mixed oxide (UO{sub 2}-TRUO{sub 2}) fuel forms have been considered with TRU feeds from weapons-grade plutonium (WG-Pu) and TRU recovered from light water reactor spent fuel (LWR-SF). Reactor performances were evaluated in detail including equilibrium cycle core parameters, mass flow, power distribution, kinetic parameters, reactivity feedback coefficient, reactivity control requirements and shutdown margins, and spent fuel characteristics. Trade-off studies on power level suggested that about 250 MWt is a reasonable compromise to allow a low project cost, at the same time providing a reasonable prototypic irradiation environment for demonstrating

  11. A Numerical Study on Possible Driving Mechanisms of Core Convection

    NASA Astrophysics Data System (ADS)

    Breuer, M.; Harder, H.; Hansen, U.

    2005-12-01

    We present a numerical study on core convection based on a model of a rotating spherical shell where different driving mechanisms are investigated. Two different sources are potentially available to act as driving forces. The first is based on the super adiabatic temperature gradient in the outer core. The second is of chemical nature and is derived from light elements which emerge at the boundary between the inner and the outer core as a result of the freezing process of the outer core. So far it is uncertain if the convective flow in the outer core is dominated by thermal or by chemical buoyancy. Dynamically, both components differ mainly in terms of their diffusional time scales, whereas the chemical component diffuses much faster than the thermal one. To investigate the influence of the driving mechanisms on the convective flow pattern we considered different scenarios including the two extreme cases of purely thermal and purely chemical driven convection and the more likely situation of a joint action of both sources. We focused on the question how the driving mechanisms affects the differential rotation and the spatial distribution of helicity which are particularly important for the dynamo process.

  12. Flexoelectric polarization studies in bent-core nematic liquid crystals.

    PubMed

    Sreenilayam, S P; Panarin, Yu P; Vij, J K; Torgova, S I; Lehmann, A; Tschierske, C

    2015-08-01

    The flexoelectric polarization (Pf) of four bent-core nematic liquid crystals (LCs) has been measured using the pyroelectric effect. Hybrid aligned nematic cells are fabricated for measuring the pyroelectric response over the entire range of the nematic phase. It is found that the magnitude of flexoelectric polarization Pf and the sum of the flexoelectric coefficients |e1+e3| for the bent-core LCs studied here are three to six times higher than for the calamitics. Pf is found to depend on the transverse dipole moment of LC molecules. However, |e1+e3| values are by no means giant as |e3| alone had been reported for a bent-core nematic system previously. The dependence of the sum of "splay and bend flexoelectric coefficients" is discussed in terms of the shape of the molecule and of the dipole moment directed normal to the molecular axis. PMID:26382418

  13. Lesson Study: The Core of Japanese Professional Development.

    ERIC Educational Resources Information Center

    Lewis, Catherine

    This paper describes research lessons, which form the core of a larger process called lesson study within Japanese elementary science faculty development. Research lessons are actual classroom lessons with students which are: observed by others; planned for a long time, usually collaboratively; designed to bring to life particular goals of…

  14. Mixed core conversion study with HEU and LEU fuels

    SciTech Connect

    Matos, J.E.; Freese, K.E.

    1984-01-01

    The results of a mixed core study are presented for gradual replacement of HEU fuel with LEU fuel using the IAEA generic 10 MW reactor as an example. The key parameters show that the transition can be accomplished safely and economically.

  15. Social Studies Core Curriculum in Fieldston Lower School.

    ERIC Educational Resources Information Center

    Kuhmerker, Lisa, Ed.

    1983-01-01

    An overview is presented of an elementary-level social studies core curriculum at Fieldston Lower School (in New York City) in which the moral and ethical development of students is seen as a priority. Fieldston Lower School is one of three branches of the Ethical Culture Schools. Article 1 focuses on the modification of the traditional elementary…

  16. Teleseismic Array Studies of Earth's Core-Mantle Boundary

    NASA Astrophysics Data System (ADS)

    Alexandrakis, Catherine

    2011-12-01

    The core mantle boundary (CMB) is an inaccessible and complex region, knowledge of which is vital to our understanding of many Earth processes. Above it is the heterogeneous lower-mantle. Below the boundary is the outer-core, composed of liquid iron, and/or nickel and some lighter elements. Elucidation of how these two distinct layers interact may enable researchers to better understand the geodynamo, global tectonics, and overall Earth history. One parameter that can be used to study structure and limit potential chemical compositions is seismic-wave velocity. Current global-velocity models have significant uncertainties in the 200 km above and below the CMB. In this thesis, these regions are studied using three methods. The upper outer core is studied using two seismic array methods. First, a modified vespa, or slant-stack method is applied to seismic observations at broadband seismic arrays, and at large, dense groups of broadband seismic stations dubbed 'virtual' arrays. Observations of core-refracted teleseismic waves, such as SmKS, are used to extract relative arrivaltimes. As with previous studies, lower -mantle heterogeneities influence the extracted arrivaltimes, giving significant scatter. To remove raypath effects, a new method was developed, called Empirical Transfer Functions (ETFs). When applied to SmKS waves, this method effectively isolates arrivaltime perturbations caused by outer core velocities. By removing raypath effects, the signals can be stacked further reducing scatter. The results of this work were published as a new 1D outer-core model, called AE09. This model describes a well-mixed outer core. Two array methods are used to detect lower mantle heterogeneities, in particular Ultra-Low Velocity Zones (ULVZs). The ETF method and beam forming are used to isolate a weak P-wave that diffracts along the CMB. While neither the ETF method nor beam forming could adequately image the low-amplitude phase, beam forms of two events indicate precursors

  17. Correction of Atmospheric Haze in RESOURCESAT-1 LISS-4 MX Data for Urban Analysis: AN Improved Dark Object Subtraction Approach

    NASA Astrophysics Data System (ADS)

    Mustak, S.

    2013-09-01

    The correction of atmospheric effects is very essential because visible bands of shorter wavelength are highly affected by atmospheric scattering especially of Rayleigh scattering. The objectives of the paper is to find out the haze values present in the all spectral bands and to correct the haze values for urban analysis. In this paper, Improved Dark Object Subtraction method of P. Chavez (1988) is applied for the correction of atmospheric haze in the Resoucesat-1 LISS-4 multispectral satellite image. Dark object Subtraction is a very simple image-based method of atmospheric haze which assumes that there are at least a few pixels within an image which should be black (% reflectance) and such black reflectance termed as dark object which are clear water body and shadows whose DN values zero (0) or Close to zero in the image. Simple Dark Object Subtraction method is a first order atmospheric correction but Improved Dark Object Subtraction method which tends to correct the Haze in terms of atmospheric scattering and path radiance based on the power law of relative scattering effect of atmosphere. The haze values extracted using Simple Dark Object Subtraction method for Green band (Band2), Red band (Band3) and NIR band (band4) are 40, 34 and 18 but the haze values extracted using Improved Dark Object Subtraction method are 40, 18.02 and 11.80 for aforesaid bands. Here it is concluded that the haze values extracted by Improved Dark Object Subtraction method provides more realistic results than Simple Dark Object Subtraction method.

  18. The study in sub E class converter with saturating cores

    NASA Astrophysics Data System (ADS)

    Suzuki, T.; Usami, K.; Yamanaka, S.

    1985-09-01

    Recently, for switching power supplies it is best to be smaller in size, with electronic equipments' miniaturization by IC technology. Sub E class dc-to-dc converter with a saturating core has the properties of high efficiency, small size, light weight and high reliability. Hence, the applications of switching regulater power supply to this technique are studied by many investigators. The results of an experiment in sub E class dc-to-dc converter with magnetic amplifier is presented.

  19. Structural and spectral studies of sunspots. [umbral core modelling

    NASA Technical Reports Server (NTRS)

    Wyller, A. A.

    1974-01-01

    Observations of umbral cores, both by multicolor photometry and by narrow band photometry in the vicinity of the sodium D lines, are described, and evidence is given which supports the validity of many umbral models, each of which describes different aspects of the observed umbral cores. Theoretical studies carried on at the observatory include the following: (1) Zeeman profiles of the sodium D sub 2 line and other lines; (2) turbulent heat conduction, sound waves, and the missing flux in sunspots; (3) chromospheric heating above spots by Alfven waves; (4) magnetic convection in the sun and solar neutrinos; (5) models of starspots on flare stars; (5) starspots on the primaries of contact binary systems; and (6) implications of starspots on red dwarfs.

  20. Neutrino oscillation studies with IceCube-DeepCore

    NASA Astrophysics Data System (ADS)

    Aartsen, M. G.; Abraham, K.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Ahrens, M.; Altmann, D.; Anderson, T.; Ansseau, I.; Archinger, M.; Arguelles, C.; Arlen, T. C.; Auffenberg, J.; Bai, X.; Barwick, S. W.; Baum, V.; Bay, R.; Beatty, J. J.; Becker Tjus, J.; Becker, K.-H.; Beiser, E.; Berghaus, P.; Berley, D.; Bernardini, E.; Bernhard, A.; Besson, D. Z.; Binder, G.; Bindig, D.; Bissok, M.; Blaufuss, E.; Blumenthal, J.; Boersma, D. J.; Bohm, C.; Börner, M.; Bos, F.; Bose, D.; Böser, S.; Botner, O.; Braun, J.; Brayeur, L.; Bretz, H.-P.; Buzinsky, N.; Casey, J.; Casier, M.; Cheung, E.; Chirkin, D.; Christov, A.; Clark, K.; Classen, L.; Coenders, S.; Collin, G. H.; Conrad, J. M.; Cowen, D. F.; Cruz Silva, A. H.; Daughhetee, J.; Davis, J. C.; Day, M.; de André, J. P. A. M.; De Clercq, C.; del Pino Rosendo, E.; Dembinski, H.; De Ridder, S.; Desiati, P.; de Vries, K. D.; de Wasseige, G.; de With, M.; DeYoung, T.; Díaz-Vélez, J. C.; di Lorenzo, V.; Dumm, J. P.; Dunkman, M.; Eberhardt, B.; Ehrhardt, T.; Eichmann, B.; Euler, S.; Evenson, P. A.; Fahey, S.; Fazely, A. R.; Feintzeig, J.; Felde, J.; Filimonov, K.; Finley, C.; Flis, S.; Fösig, C.-C.; Fuchs, T.; Gaisser, T. K.; Gaior, R.; Gallagher, J.; Gerhardt, L.; Ghorbani, K.; Gier, D.; Gladstone, L.; Glagla, M.; Glüsenkamp, T.; Goldschmidt, A.; Golup, G.; Gonzalez, J. G.; Góra, D.; Grant, D.; Griffith, Z.; Groß, A.; Ha, C.; Haack, C.; Haj Ismail, A.; Hallgren, A.; Halzen, F.; Hansen, E.; Hansmann, B.; Hanson, K.; Hebecker, D.; Heereman, D.; Helbing, K.; Hellauer, R.; Hickford, S.; Hignight, J.; Hill, G. C.; Hoffman, K. D.; Hoffmann, R.; Holzapfel, K.; Homeier, A.; Hoshina, K.; Huang, F.; Huber, M.; Huelsnitz, W.; Hulth, P. O.; Hultqvist, K.; In, S.; Ishihara, A.; Jacobi, E.; Japaridze, G. S.; Jeong, M.; Jero, K.; Jones, B. J. P.; Jurkovic, M.; Kappes, A.; Karg, T.; Karle, A.; Kauer, M.; Keivani, A.; Kelley, J. L.; Kemp, J.; Kheirandish, A.; Kiryluk, J.; Klein, S. R.; Kohnen, G.; Koirala, R.; Kolanoski, H.; Konietz, R.; Köpke, L.; Kopper, C.; Kopper, S.; Koskinen, D. J.; Kowalski, M.; Krings, K.; Kroll, G.; Kroll, M.; Krückl, G.; Kunnen, J.; Kurahashi, N.; Kuwabara, T.; Labare, M.; Lanfranchi, J. L.; Larson, M. J.; Lesiak-Bzdak, M.; Leuermann, M.; Leuner, J.; Lu, L.; Lünemann, J.; Madsen, J.; Maggi, G.; Mahn, K. B. M.; Mandelartz, M.; Maruyama, R.; Mase, K.; Matis, H. S.; Maunu, R.; McNally, F.; Meagher, K.; Medici, M.; Meli, A.; Menne, T.; Merino, G.; Meures, T.; Miarecki, S.; Middell, E.; Mohrmann, L.; Montaruli, T.; Morse, R.; Nahnhauer, R.; Naumann, U.; Neer, G.; Niederhausen, H.; Nowicki, S. C.; Nygren, D. R.; Obertacke Pollmann, A.; Olivas, A.; Omairat, A.; O'Murchadha, A.; Palczewski, T.; Pandya, H.; Pankova, D. V.; Paul, L.; Pepper, J. A.; Pérez de los Heros, C.; Pfendner, C.; Pieloth, D.; Pinat, E.; Posselt, J.; Price, P. B.; Przybylski, G. T.; Quinnan, M.; Raab, C.; Rädel, L.; Rameez, M.; Rawlins, K.; Reimann, R.; Relich, M.; Resconi, E.; Rhode, W.; Richman, M.; Richter, S.; Riedel, B.; Robertson, S.; Rongen, M.; Rott, C.; Ruhe, T.; Ryckbosch, D.; Sabbatini, L.; Sander, H.-G.; Sandrock, A.; Sandroos, J.; Sarkar, S.; Schatto, K.; Schimp, M.; Schmidt, T.; Schoenen, S.; Schöneberg, S.; Schönwald, A.; Schulte, L.; Schumacher, L.; Seckel, D.; Seunarine, S.; Soldin, D.; Song, M.; Spiczak, G. M.; Spiering, C.; Stahlberg, M.; Stamatikos, M.; Stanev, T.; Stasik, A.; Steuer, A.; Stezelberger, T.; Stokstad, R. G.; Stößl, A.; Ström, R.; Strotjohann, N. L.; Sullivan, G. W.; Sutherland, M.; Taavola, H.; Taboada, I.; Tatar, J.; Ter-Antonyan, S.; Terliuk, A.; Tešić, G.; Tilav, S.; Toale, P. A.; Tobin, M. N.; Toscano, S.; Tosi, D.; Tselengidou, M.; Turcati, A.; Unger, E.; Usner, M.; Vallecorsa, S.; Vandenbroucke, J.; van Eijndhoven, N.; Vanheule, S.; van Santen, J.; Veenkamp, J.; Vehring, M.; Voge, M.; Vraeghe, M.; Walck, C.; Wallace, A.; Wallraff, M.; Wandkowsky, N.; Weaver, Ch.; Wendt, C.; Westerhoff, S.; Whelan, B. J.; Wiebe, K.; Wiebusch, C. H.; Wille, L.; Williams, D. R.; Wills, L.; Wissing, H.; Wolf, M.; Wood, T. R.; Woschnagg, K.; Xu, D. L.; Xu, X. W.; Xu, Y.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Zoll, M.

    2016-07-01

    IceCube, a gigaton-scale neutrino detector located at the South Pole, was primarily designed to search for astrophysical neutrinos with energies of PeV and higher. This goal has been achieved with the detection of the highest energy neutrinos to date. At the other end of the energy spectrum, the DeepCore extension lowers the energy threshold of the detector to approximately 10 GeV and opens the door for oscillation studies using atmospheric neutrinos. An analysis of the disappearance of these neutrinos has been completed, with the results produced being complementary with dedicated oscillation experiments. Following a review of the detector principle and performance, the method used to make these calculations, as well as the results, is detailed. Finally, the future prospects of IceCube-DeepCore and the next generation of neutrino experiments at the South Pole (IceCube-Gen2, specifically the PINGU sub-detector) are briefly discussed.

  1. Comparative study of the physical properties of core materials.

    PubMed

    Saygili, Gülbin; Mahmali, Sevil M

    2002-08-01

    This study was undertaken to measure physical properties of materials used for direct core buildups, including high-copper amalgam, visible light-cured resin composite, autocured titanium-containing composite, polyacid-modified composite, resin-modified glass-ionomer, and silver cermet cement. Compressive strength, diametral tensile strength, and flexural strength of six core materials of various material classes were measured for each material as a function of time up to 3 months at different storage conditions, using a standard specification test designed for the materials. Three different storage conditions (dry, humid, wet) at 37 degrees C were chosen. Materials were manipulated according to manufacturers' instructions for use as cores. Mean compressive, diametral tensile, and flexural strengths with associated standard deviations were calculated for each material. Multiple comparison and Newman-Keuls tests discerned many differences among materials. All materials were found to meet the minimum specification requirements, except in terms of flexural strength for amalgam after 1 hour and the silver cermet at all time intervals. PMID:12212682

  2. Multi-Core Processor Memory Contention Benchmark Analysis Case Study

    NASA Technical Reports Server (NTRS)

    Simon, Tyler; McGalliard, James

    2009-01-01

    Multi-core processors dominate current mainframe, server, and high performance computing (HPC) systems. This paper provides synthetic kernel and natural benchmark results from an HPC system at the NASA Goddard Space Flight Center that illustrate the performance impacts of multi-core (dual- and quad-core) vs. single core processor systems. Analysis of processor design, application source code, and synthetic and natural test results all indicate that multi-core processors can suffer from significant memory subsystem contention compared to similar single-core processors.

  3. Assessment of land degradation hazards, Jamui district India using IRS P6 LISS-III multi-temporal satellite data

    NASA Astrophysics Data System (ADS)

    Londhe, S.; Talukdar, G.; Deshmukh, B.; Srivastava, S.

    2009-04-01

    Asian region is under high pressure to supply required food for rapidly increasing population. This, together with harsh climatic conditions and changes in land use accelerates land degradation process, which eventually leads to yield reduction. Soil erosion is one of the mode of land degradation and serious problem in granitic terrains of Semi-arid regions. This accounts the loss of fertile soil through detachment and transportation from one place and deposition to another place resulting in decreased soil fertility and reduced crop yields as well as sedimentation of rivers and reservoirs. IRSP6 LISS-III satellite data of three different season viz. Khrif, rabi and summer data in conjunction of with Survey of India toposheets and subsequent ground truth has been used for assessment of land degradation using onscreen visual interpretation. Based on severity of degradation the area is mapped into sheet erosion, rill erosion, gully erosion, ravenous erosion, seasonal waterlogging and rock out crops. The complex degradation problems having more than one degradation processes were appropriately represented in the mapping unit as combination. In order to understand the associated land use and feasibility of reclamination of degraded lands different landforms are identified along with land use level 1 classification. It was observed that 23.2 % of the total area (3044.5 km2) of the district is under sheet erosion followed by rill erosion 33.5 %, gully erosion 13.3% and ravenous erosion 0.4%. Highly degraded area, rock out crops is associated with higher elements of slope and barren areas accounts for 2.0%. The seasonal waterlogging is associated with lower elements of slope in depression where there is no facility for water to drain out through surface or sub-surface drainage and affecting agricultural activities which occupy 0.90% area in the district. Around 26.8 % area of the Jamui district is depicted as not affected due to degradation process due to its lower slopes

  4. Spectroscopic studies of Synechococcus sp PCC 7002 phycobilisome core mutants

    SciTech Connect

    Gindt, Y.M.

    1993-04-01

    The role of the L{sub cm} (I), {beta}{sup 18} (II), and {alpha}{sup AP-B} (III) chromoproteins in the phycobilisome (PBS) core was investigated using genetically engineered strains of Synechococcus missing different polypeptides. Intact cells, isolated PBS, and subcore preparations for each mutant were studied to determine the effect of that mutation on energy transfer within the PBS core and to the reaction centers. Three mutants lacked the II and/or III polypeptides, while the I chromophore was altered in others. A lower energy absorbing chromophore, A{sub max} = 695 nm, was substituted for the I chromophore. The deletion of the II and III subunits had no discernible effect on energy transfer from the PBS to PSII. In cells and isolated PBS, the altered I chromophore acts to quench the PBS complex and to redirect the energy which would be transferred to PSII. In the PBS and subcore preparations, deletion of the III subunit did not alter energy transfer within the core. The deletion of the II subunit from the PBS caused a small decrease in the excited state lifetimes of the final emitters indicating more disorder within the core. The I chromophore was found to absorb at 670nm and to emit at 683nm within the intact PBS. The II chromophore emits at 679nm while the III chromophore emits at 682nm. A strong interaction exists between the I chromophore and the II subunit. Upon deletion of the II subunit from the PBS core, the I chromophore emits at a higher energy. The II subunit could act to stabilize the I chromophore-binding pocket, or exciton coupling could be occurring between the two. The role of the III chromophore is still unclear at this time. The III chromophore does contribute to the RT emission of the isolated PBS, but it transfers energy to I at 77 K. One can conclude that the III subunit is adjacent to the trimer containing the I polypeptide.

  5. Spectroscopic studies of Synechococcus sp PCC 7002 phycobilisome core mutants

    SciTech Connect

    Gindt, Y.M.

    1993-04-01

    The role of the L[sub cm] (I), [beta][sup 18] (II), and [alpha][sup AP-B] (III) chromoproteins in the phycobilisome (PBS) core was investigated using genetically engineered strains of Synechococcus missing different polypeptides. Intact cells, isolated PBS, and subcore preparations for each mutant were studied to determine the effect of that mutation on energy transfer within the PBS core and to the reaction centers. Three mutants lacked the II and/or III polypeptides, while the I chromophore was altered in others. A lower energy absorbing chromophore, A[sub max] = 695 nm, was substituted for the I chromophore. The deletion of the II and III subunits had no discernible effect on energy transfer from the PBS to PSII. In cells and isolated PBS, the altered I chromophore acts to quench the PBS complex and to redirect the energy which would be transferred to PSII. In the PBS and subcore preparations, deletion of the III subunit did not alter energy transfer within the core. The deletion of the II subunit from the PBS caused a small decrease in the excited state lifetimes of the final emitters indicating more disorder within the core. The I chromophore was found to absorb at 670nm and to emit at 683nm within the intact PBS. The II chromophore emits at 679nm while the III chromophore emits at 682nm. A strong interaction exists between the I chromophore and the II subunit. Upon deletion of the II subunit from the PBS core, the I chromophore emits at a higher energy. The II subunit could act to stabilize the I chromophore-binding pocket, or exciton coupling could be occurring between the two. The role of the III chromophore is still unclear at this time. The III chromophore does contribute to the RT emission of the isolated PBS, but it transfers energy to I at 77 K. One can conclude that the III subunit is adjacent to the trimer containing the I polypeptide.

  6. Isotope Fractionation Studies in Prestellar Cores: The Case of Nitrogen

    NASA Technical Reports Server (NTRS)

    Milam, Stefanie N.; Charnley, Steven B.

    2011-01-01

    Isotopically fractionated material is found in many solar system objects, including meteorites and comets. It is considered, in some cases, to trace interstellar material that was incorporated into the solar system without undergoing significant processing, thus preserving the fractionation. In interstellar molecular clouds, ion-molecule chemistry continually cycles nitrogen between the two main reservoirs - N and N2 - leading to only minor N-15 enrichments. Charnley and Rodgers showed that depletion of CO removes oxygen from the gas and weakens this cycle such that significant N-15 fractionation can occur for N2 and other N-bearing species in such cores. Observations are being conducted at millimeter and submillimeter wavelengths employing various facilities in order to both spatially and spectrally, resolve emission from these cores. A preliminary study to obtain the N-14/N-15 ratio in nitriles (HCN and HNC) was conducted at the Arizona Radio Observatory's 12m telescope on Kitt Peak, AZ. Spectra were obtained at high resolution (0.08 km/s) in order to resolve dynamic properties of each source as well as to resolve hyperfine structure present in certain isotopologues. This study included four dark cloud cores, observed to have varying levels of molecular depletion: L1521E, L1498, L1544, and L1521F. Previous studies of the N-14/N-15 ratio towards LI544 were obtained with N2H+ and NIH3, yielding ratios of 446 and >700, respectively. The discrepancy observed in these two measurements suggests a strong chemical dependence on the fractionation of nitrogen. Ratios (C,N, and D) obtained from isotopologues for a particular molecule are likely tracing the same chemical heritage and are directly comparable within a given source. Results and comparisons between the protostellar evolutionary state and isomer isotope fractionation as well as between other N-bearing species will be presented.

  7. Preliminary design study of advanced multistage axial flow core compressors

    NASA Technical Reports Server (NTRS)

    Wisler, D. C.; Koch, C. C.; Smith, L. H., Jr.

    1977-01-01

    A preliminary design study was conducted to identify an advanced core compressor for use in new high-bypass-ratio turbofan engines to be introduced into commercial service in the 1980's. An evaluation of anticipated compressor and related component 1985 state-of-the-art technology was conducted. A parametric screening study covering a large number of compressor designs was conducted to determine the influence of the major compressor design features on efficiency, weight, cost, blade life, aircraft direct operating cost, and fuel usage. The trends observed in the parametric screening study were used to develop three high-efficiency, high-economic-payoff compressor designs. These three compressors were studied in greater detail to better evaluate their aerodynamic and mechanical feasibility.

  8. Doppler Scanning of Sediment Cores: A Useful Method for Studying Sedimentary Structures and Defining the Cutting Angle for Half Cores

    NASA Astrophysics Data System (ADS)

    Acar, Dursun; Cagatay, Namik; Biltekin, Demet; Eris, Kadir; Albut, Gulum; Ogretmen, Nazik; Arslan, Tugce; Sari, Erol

    2014-05-01

    We tested the doppler ultrasound scanning of sediment cores in PVC liners using 8 megahertz ultrasonic waves for detection of angular laminations. The method was tested with artificially prepared cores as well as marine and lake sediment cores, and proven to be a useful and fast technique for imaging and determining the vertical angularity of sedimentary structures, such as laminations and beddings. Random cutting axes provide two angularities on X and Y dimensions. In this study, the main scientific problem is 'sequential angular disconformity'. Importance of detection of these anomalies on whole cores before dividing into half cores based on determining the right cutting axes. Successful imaging was obtained from top three centimeter depth of the sediments below the PVC liner, using a linear Doppler probe. Other Doppler probes (e.g., convex probe) did not work for core scanning because of their wave-form and reflection characteristics. Longitudinal and rotational scanning with gap filler and ultrasonic wave conductive gel material for keeping energy range of wave is necessary for detecting the variation in the dip of the bedding and laminae in the cores before separation. Another angular reasoned problem is about horizontal surface and can be easily solved with adjustable position of sensor or ray source placement. Border of sampling points between two different lithology must be stay with regard to neighbour sediment angles. Vertical angularity correction is not easy and its effect on signal propagation, detection biases and effectible to mixed samples contamination during physical sampling (particle size analyzing). Determining the attitude of angled bedding before core splitting is important for further core analyses such as elemental analysis and digital X-ray radiography. After Doppler scanning, the splitting direction (i.e., vertical to bedding and lamination) can be determined. The method is cheap, quick and non- hazardous to health, unlike the x

  9. Experimental study of the Biot coefficient of Bakken cores

    NASA Astrophysics Data System (ADS)

    Ma, X.; Zoback, M. D.

    2015-12-01

    We have performed a series of exhaustive experiments to measure the Biot coefficient (α) of the tight cores from the Bakken shale oil play. Five distinct, bedding-normal cores from a vertical well were tested, covering the sequences of Three Forks, Lower, Middle, and Upper Bakken, and Lodgepole. The scope of this laboratory study is two-fold: (1) to obtain realistic Biot coefficient for modeling reservoir stress changes due to depletion and injection; (2) to characterize the poromechanical properties in relation to rock's mineral composition and microstructure. The experiments were carried out as follows: Argon-saturated specimen (1-inch length, 1-inch diameter) was subjected to hydrostatic confining pressure under drained conditions. Pore pressure was regulated as Argon was injected into both ends of the specimen. We drilled multiple non-through-going boreholes (1-mm diameter) in the specimen to facilitate pressure equilibrium, without compromising its integrity. The specimen was put through a loading path to experience confining pressure and pore pressure up to 70 and 60 MPa, respectively. Axial and lateral strains were recorded and used to calculate the rock's bulk stiffness, and subsequently the static Biot coefficient, which is related to reservoir deformation and associated stress changes. Results of all five cores unanimously show that α is less than unity and is a function of both confining and pore pressure. α generally varies between 0.3 and 0.9 for the pressure levels we applied. This implies that models of reservoir deformation and its stress change using Terzaghi's simple effective stress law (α = 1) or a constant α less than 1 may be erroneous. Typically, α rises significantly with pore pressure, but declines with confining pressure to the degree that is dependent on rock's bulk stiffness. We found the stiffness of these rocks does not correlate well with the content of compliant components (e.g., clay and kerogen), and the drastic difference in

  10. Study on Spatial Cultural Heritage Integrated into the Core Curriculum

    NASA Astrophysics Data System (ADS)

    Hsu, W. H.; Lai, Y. P.

    2015-08-01

    These Many countries have put a lot of efforts, promoting education of cultural heritage, to raise the conservation awareness and increase people's participation. However, the development of Taiwan's higher education about cultural heritage has not shown a significant growth, so it didn't train talents with enough cultural heritage awareness. In the workplace, these professionals will inevitably lack of comprehensions and the appropriate professional assessments for cultural heritage. Hence, the main objective of this paper is to study and combine these concepts into the core curriculum of Department of Construction and Spatial Design at Tungnan University. It takes the local "Shenkeng historic cultural district" as a case study, and will gradually develop an proper interdisciplinary course in order to help local residents implement projects of conserving cultural heritage. This plan not only can increase schools' engagements toward communities, with an ability of social civilization, but also it can encourage the conservation and maintenance of cultural heritages.

  11. Secondary Social Studies Teachers' Experiences Implementing Common Core State Literacy Standards: A Phenomenological Study

    ERIC Educational Resources Information Center

    Webb, Krista Faith Huskey

    2014-01-01

    The purpose of this phenomenological study was to examine the experiences of secondary social studies teachers who implemented Common Core State Standards for English Language Arts & Literacy in history/social studies, science and technical subjects in social studies courses requiring End of Course Tests at secondary schools in one suburban…

  12. Core Outcomes for Colorectal Cancer Surgery: A Consensus Study

    PubMed Central

    Whistance, Robert N.; Forsythe, Rachael O.; Macefield, Rhiannon; Pullyblank, Anne M.; Avery, Kerry N. L.; Brookes, Sara T.; Thomas, Michael G.; Sylvester, Paul A.; Russell, Ann; Oliver, Alfred; Morton, Dion; Kennedy, Robin; Jayne, David G.; Huxtable, Richard; Hackett, Roland; Card, Mia; Brown, Julia; Blazeby, Jane M.

    2016-01-01

    Background Colorectal cancer (CRC) is a major cause of worldwide morbidity and mortality. Surgical treatment is common, and there is a great need to improve the delivery of such care. The gold standard for evaluating surgery is within well-designed randomized controlled trials (RCTs); however, the impact of RCTs is diminished by a lack of coordinated outcome measurement and reporting. A solution to these issues is to develop an agreed standard “core” set of outcomes to be measured in all trials to facilitate cross-study comparisons, meta-analysis, and minimize outcome reporting bias. This study defines a core outcome set for CRC surgery. Methods and Findings The scope of this COS includes clinical effectiveness trials of surgical interventions for colorectal cancer. Excluded were nonsurgical oncological interventions. Potential outcomes of importance to patients and professionals were identified through systematic literature reviews and patient interviews. All outcomes were transcribed verbatim and categorized into domains by two independent researchers. This informed a questionnaire survey that asked stakeholders (patients and professionals) from United Kingdom CRC centers to rate the importance of each domain. Respondents were resurveyed following group feedback (Delphi methods). Outcomes rated as less important were discarded after each survey round according to predefined criteria, and remaining outcomes were considered at three consensus meetings; two involving international professionals and a separate one with patients. A modified nominal group technique was used to gain the final consensus. Data sources identified 1,216 outcomes of CRC surgery that informed a 91 domain questionnaire. First round questionnaires were returned from 63 out of 81 (78%) centers, including 90 professionals, and 97 out of 267 (35%) patients. Second round response rates were high for all stakeholders (>80%). Analysis of responses lead to 45 and 23 outcome domains being retained

  13. From the Common Core to the Classroom: A Professional Development Efficacy Study for the Common Core State Standards for Mathematics

    ERIC Educational Resources Information Center

    Rimbey, Kimberly A.

    2013-01-01

    In this mixed-methods study, I examined the relationship between professional development based on the Common Core State Standards for Mathematics and teacher knowledge, classroom practice, and student learning. Participants were randomly assigned to experimental and control groups. The 50-hour professional development treatment was administered…

  14. A Deuterium NMR Study of Bent-Core Liquid Crystals

    NASA Astrophysics Data System (ADS)

    Dingemans, Theo J.; Madsen, Louis A.; Samulski, Edward T.

    2002-10-01

    We have synthesized two deuterated boomerang-shaped liquid crystals based on 2,5-bis(4-hydroxyphenyl)-1,3,4-oxadiazole (ODBP). Deuterium was introduced in the rigid 2,5-diphenyl-1,3,4-oxadiazole core and in the aromatic ring of the terminal 4-dodecyloxyphenyl moiety using standard acid catalyzed deuterium exchange conditions. Both compounds, (4,4'(1,3,4-oxadiazole-2,5-diyl-d4) di-4-dodecyloxybenzoate: ODBP-d4-Ph-O-C12) and (4,4'(1,3,4-oxadiazole-2,5-diyl) di-4-dodecyloxy-benzoate-d4; ODBP-Ph-d4-O-C12) were investigated by nuclear magnetic resonance, optical microscopy and differential scanning calorimetry. The optical textures and thermal behavior of both compounds were found to be identical to the non-deuterated analog 4,4(1,3,4-oxadiazole-2,5-diyl) di-4-dodecyloxybenzoate (ODBP-Ph-O-C12) which we reported earlier. These compounds exhibit behavior indicative of a biaxial nematic liquid crystal phase, which we hope to confirm using deuterium NMR spectroscopy in the next phase of this study.

  15. Monitoring of Western Corn Rootworm Damage in Maize Fields by Using Integrated Radar (ALOS PALSAR) and Optical (IRS LISS, AWiFS) Satellite Data

    NASA Astrophysics Data System (ADS)

    Nador, Gizella; Fenyes, Diana; Surek, Gyorgy; Vasas, Laszlo

    2008-11-01

    The gradual dispersion of western corn rootworm (WCR) is becoming a serious maize pest in Europe, and all over the world. In 2008 using remote sensing data, the Remote Sensing Centre of Institute of Geodesy, Cartography and Remote Sensing (FÖMI RSC) carried out this project to identify WCR larval damage. Our goal with the present project is to assess and identify the disorder and structural changes caused by WCR larvae using optical (IRS-P6 AWiFS, IRS-P6 LISS, SPOT4 and SPOT5) and polarimetic radar (ALOS PALSAR) satellite images. The project aims to identify the extent of WCR damaged cornfields using both polarimetic radar images and optical satellite data time series. Findings were tested against on-the-spot ground assessments. Using radar polarimetry increased the accuracy significantly. The final results have implications for plant protection strategy, farming practices, pesticide producers, state authorities and research institutes.

  16. Physical studies of small asteroids and cometary cores

    NASA Technical Reports Server (NTRS)

    Wisniewski, Wieslaw Z.

    1988-01-01

    The main goal of the research is to carry on an extensive study of physical properties (colors and variability) of asteroids in the 1 to 10 km diameter range and of cometary cores, with the use of a charge coupled device (CCD) camera, PMT photometer, or both. Particular attention is paid to asteroids being observed by radar because the greatest gain is found from the combination of radar results with the data obtained by optical techniques. To satisfy the goal, 100 nights/year have been scheduled on the 2.3 m and 1.5 m telescopes. During the past 2 years small asteroids were observed. Out of 22 asteroids for which periods of rotation could be precisely measured, 17 have periods of rotation less than 5 hours. This indicates that small objects rotate faster. By now researchers know 14 asteroids with rotation periods in the 2 hour range. At the same time they confirmed the existence of a number of exceptionally slow rotators e.g., 1367 Nongoma with P = 5.65 days. Taxonomic observations lead to a conclusion that Apollo, Amor, and Aten asteroids represent a variety of classes and are not predominantly of class S. Apollo asteroid 3361 Orpheus was found to belong to the rare class V. In collaboration with Dr A. Harris of JPL the opposition effect was studied for 30 Urania and 64 Angelina. Seven comets: P/Helin, P/Brooks 2, P/Klemola, P/Borrelly, Wilson (1986 1) and Shoemaker (1987 o) were monitored for variability. The results were negative with the exception of P/Brooks 2 for which 0.35 mag amplitude was detected.

  17. Study of High-Efficiency Motors Using Soft Magnetic Cores

    NASA Astrophysics Data System (ADS)

    Tokoi, Hirooki; Kawamata, Shoichi; Enomoto, Yuji

    We have been developed a small and highly efficient axial gap motor whose stator core is made of a soft magnetic core. First, the loss sensitivities to various motor design parameters were evaluated using magnetic field analysis. It was found that the pole number and core dimensions had low sensitivity (≤ 2.2dB) in terms of the total loss, which is the sum of the copper loss and the iron losses in the stator core and the rotor yoke respectively. From this, we concluded that to improve the motor efficiency, it is essential to reduce the iron loss in the rotor yoke and minimize other losses. With this in mind, a prototype axial gap motor is manufactured and tested. The motor has four poles and six slots. The motor is 123mm in diameter and the axial length is 47mm. The rotor has parallel magnetized magnets and a rotor yoke with magnetic steel sheets. The maximum measured motor efficiency is 93%. This value roughly agrees with the maximum calculated efficiency of 95%.

  18. Feasibility Studies of Teacher Core Job Characteristics. Final Report.

    ERIC Educational Resources Information Center

    Charters, W. W., Jr.; And Others

    Work redesign for improving satisfaction or productivity depends partially on employee attributes because employees respond differently to work conditions. The Hackman-Oldham theory distinguishes "job" from employee responses to job. A job's motivating potential is thus linked to five core characteristics that affect three psychological states…

  19. A study of the core module simulator floor capability

    NASA Technical Reports Server (NTRS)

    Foreman, James W.

    1993-01-01

    The floor of the Core Module Simulator (CMS) is required to support various combinations of dead load and live load during the testing process. Even though there is published data on the structural capability of the grating, it is not always evident if the combined loadings with joint loads will cause structural failure.

  20. Soft-core processor study for node-based architectures.

    SciTech Connect

    Van Houten, Jonathan Roger; Jarosz, Jason P.; Welch, Benjamin James; Gallegos, Daniel E.; Learn, Mark Walter

    2008-09-01

    Node-based architecture (NBA) designs for future satellite projects hold the promise of decreasing system development time and costs, size, weight, and power and positioning the laboratory to address other emerging mission opportunities quickly. Reconfigurable Field Programmable Gate Array (FPGA) based modules will comprise the core of several of the NBA nodes. Microprocessing capabilities will be necessary with varying degrees of mission-specific performance requirements on these nodes. To enable the flexibility of these reconfigurable nodes, it is advantageous to incorporate the microprocessor into the FPGA itself, either as a hardcore processor built into the FPGA or as a soft-core processor built out of FPGA elements. This document describes the evaluation of three reconfigurable FPGA based processors for use in future NBA systems--two soft cores (MicroBlaze and non-fault-tolerant LEON) and one hard core (PowerPC 405). Two standard performance benchmark applications were developed for each processor. The first, Dhrystone, is a fixed-point operation metric. The second, Whetstone, is a floating-point operation metric. Several trials were run at varying code locations, loop counts, processor speeds, and cache configurations. FPGA resource utilization was recorded for each configuration. Cache configurations impacted the results greatly; for optimal processor efficiency it is necessary to enable caches on the processors. Processor caches carry a penalty; cache error mitigation is necessary when operating in a radiation environment.

  1. Numerical studies of the margin of vortices with decaying cores

    NASA Technical Reports Server (NTRS)

    Liu, G. C.; Ting, L.

    1986-01-01

    The merging of vortices to a single one is a canonical incompressible viscous flow problem. The merging process begins when the core sizes or the vortices are comparable to their distances and ends when the contour lines of constant vorticity lines are circularized around one center. Approximate solutions to this problem are constructed by adapting the asymptotic solutions for distinct vortices. For the early stage of merging, the next-order terms in the asymptotic solutions are added to the leading term. For the later stage of merging, the vorticity distribution is reinitialized by vortices with overlapping core structures guided by the 'rule of merging' and the velocity of the 'vortex centers' are then defined by a minimum principle. To show the accuracy of the approximate solution, it is compared with the finite-difference solution.

  2. Positron Annihilation Spectroscopy Study of Barnett Shale Core

    NASA Astrophysics Data System (ADS)

    Ameena, Fnu; Alsleben, Helge; Quarles, Carroll A.

    Measurements are reported of positron annihilation lifetime and Doppler broadening parameters on 14 samples of Barnett shale core selected from 196 samples ranging from depths of 6107 to 6402 feet. The Barnett shale core was taken from EOG well Two-O-Five 2H located in Johnson county TX. The selected samples are dark clay-rich mudstone consisting of fine-grained clay minerals. The samples are varied in shape, typically a few inches long and about 1/2 inch in width and thickness, and are representative of the predominant facies in the core. X-ray fluorescence (XRF), X-ray diffraction (XRD), petrographic analysis and geochemical analysis of total organic carbon (TOC) were already available for each of the selected samples. The lifetime data are analyzed in terms of three lifetime components with the shortest lifetime fixed at 125 ps. The second lifetime is attributed to positron annihilation in the bulk and positron trapping; and the third lifetime is due to positronium. Correlations of the lifetimes, intensities, the average lifetime and S and W parameters with TOC, XRF and XRD parameters are discussed. The observed correlations suggest that positron spectroscopy may be a useful tool in characterizing shale.

  3. Core compressor exit stage study. 1: Aerodynamic and mechanical design

    NASA Technical Reports Server (NTRS)

    Burdsall, E. A.; Canal, E., Jr.; Lyons, K. A.

    1979-01-01

    The effect of aspect ratio on the performance of core compressor exit stages was demonstrated using two three stage, highly loaded, core compressors. Aspect ratio was identified as having a strong influence on compressors endwall loss. Both compressors simulated the last three stages of an advanced eight stage core compressor and were designed with the same 0.915 hub/tip ratio, 4.30 kg/sec (9.47 1bm/sec) inlet corrected flow, and 167 m/sec (547 ft/sec) corrected mean wheel speed. The first compressor had an aspect ratio of 0.81 and an overall pressure ratio of 1.357 at a design adiabatic efficiency of 88.3% with an average diffusion factor or 0.529. The aspect ratio of the second compressor was 1.22 with an overall pressure ratio of 1.324 at a design adiabatic efficiency of 88.7% with an average diffusion factor of 0.491.

  4. A PILOT STUDY OF CORE STABILITY AND ATHLETIC PERFORMANCE: IS THERE A RELATIONSHIP?

    PubMed Central

    Sharrock, Chris; Cropper, Jarrod; Mostad, Joel; Johnson, Matt

    2011-01-01

    Study Design: Correlation study Objectives: To objectively evaluate the relationship between core stability and athletic performance measures in male and female collegiate athletes. Background: The relationship between core stability and athletic performance has yet to be quantified in the available literature. The current literature does not demonstrate whether or not core strength relates to functional performance. Questions remain regarding the most important components of core stability, the role of sport specificity, and the measurement of core stability in relation to athletic performance. Methods: A sample of 35 volunteer student athletes from Asbury College (NAIA Division II) provided informed consent. Participants performed a series of five tests: double leg lowering (core stability test), the forty yard dash, the T-test, vertical jump, and a medicine ball throw. Participants performed three trials of each test in a randomized order. Results: Correlations between the core stability test and each of the other four performance tests were determined using a General Linear Model. Medicine ball throw negatively correlated to the core stability test (r –0.389, p=0.023). Participants that performed better on the core stability test had a stronger negative correlation to the medicine ball throw (r =–0.527). Gender was the most strongly correlated variable to core strength, males with a mean measurement of double leg lowering of 47.43 degrees compared to females having a mean of 54.75 degrees. Conclusions: There appears to be a link between a core stability test and athletic performance tests; however, more research is needed to provide a definitive answer on the nature of this relationship. Ideally, specific performance tests will be able to better define and to examine relationships to core stability. Future studies should also seek to determine if there are specific sub-categories of core stability which are most important to allow for optimal training and

  5. The Incomplete Impact Record and Implications for Ice Core Studies

    NASA Astrophysics Data System (ADS)

    Bay, R. C.; Rohde, R. A.; Price, P. B.

    2007-12-01

    The impact risk is extremely uncertain for objects of order 0.1-1 km diameter, with kinetic energies in the range 100 to 1 million Mt (megaton TNT ~ 4×1015 J) and recurrence times estimated in thousands to many tens of thousands of years. Millennial timescales are especially interesting, since the character of explosions (e.g. impacts, large volcanic eruptions) that only occur every 103 to 104 years lies just beyond the reckoning of modern cultural history. The impact rate predicted for the Earth based on observing nearby objects is much higher than the endemic rate estimated by counting known craters on Earth's surface. We have examined the latest account of confirmed craters from the Earth Impact Database (http://www.unb.ca/passc/ImpactDatabase/) over the last 100 Ma. The cratering record contains a large gap between 35 and 5 Ma, during which the apparent impact rate drops by an order of magnitude. The gap occurs during a period of substantial climate change, notably the initiation of large scale permanent glaciers, based on climate proxies from deep-sea sediment cores. A likely partial explanation is that climate change eroded or precluded crater formation in the recent geologic past. Taken together with constraints from inner solar system cratering and observations of near earth objects, the apparent gap in crater formation suggests that the terrestrial impact record is grossly incomplete over timescales much shorter than 100 Ma. If the true impact rate is more commensurate with the higher rates inferred from the local planetary environment, then some of the explosive fallout layers now observed in ice cores may actually be the result of recent impacts rather than volcanic eruptions. Like very large eruptions, impact ejecta are likely to be widely distributed, since impactors disrupt all levels of the atmosphere and generate ballistic debris and vapor plumes that can rise above the stratosphere. Polar ice core records of the last ~50-100 ka have become

  6. Feasibility study on nuclear core design for soluble boron free small modular reactor

    SciTech Connect

    Rabir, Mohamad Hairie Hah, Chang Joo; Ju, Cho Sung

    2015-04-29

    A feasibility study on nuclear core design of soluble boron free (SBF) core for small size (150MWth) small modular reactor (SMR) was investigated. The purpose of this study was to design a once through cycle SMR core, where it can be used to supply electricity to a remote isolated area. PWR fuel assembly design with 17×17 arrangement, with 264 fuel rods per assembly was adopted as the basis design. The computer code CASMO-3/MASTER was used for the search of SBF core and fuel assembly analysis for SMR design. A low critical boron concentration (CBC) below 200 ppm core with 4.7 years once through cycle length was achieved using 57 fuel assemblies having 170 cm of active height. Core reactivity controlled using mainly 512 number of 4 wt% and 960 12 wt% Gd rods.

  7. Feasibility study on nuclear core design for soluble boron free small modular reactor

    NASA Astrophysics Data System (ADS)

    Rabir, Mohamad Hairie; Hah, Chang Joo; Ju, Cho Sung

    2015-04-01

    A feasibility study on nuclear core design of soluble boron free (SBF) core for small size (150MWth) small modular reactor (SMR) was investigated. The purpose of this study was to design a once through cycle SMR core, where it can be used to supply electricity to a remote isolated area. PWR fuel assembly design with 17×17 arrangement, with 264 fuel rods per assembly was adopted as the basis design. The computer code CASMO-3/MASTER was used for the search of SBF core and fuel assembly analysis for SMR design. A low critical boron concentration (CBC) below 200 ppm core with 4.7 years once through cycle length was achieved using 57 fuel assemblies having 170 cm of active height. Core reactivity controlled using mainly 512 number of 4 wt% and 960 12 wt% Gd rods.

  8. Lessons Learned in Conducting a Lottery-Based Study of Core Knowledge Charter Schools

    ERIC Educational Resources Information Center

    White, Thomas G.; Grissmer, David W.; Altenhofen, Shannon; Larson, Jennifer

    2013-01-01

    The authors are presently in the fourth year of a six-year, lottery-based randomized control trial (RCT) studying the effectiveness of nine Colorado charter schools that have implemented Core Knowledge®. Core Knowledge (CK) is a comprehensive K-8 curriculum for language arts, math, science, social studies, visual arts, and music that is intended…

  9. System Study: High-Pressure Core Spray 1998–2012

    SciTech Connect

    T. E. Wierman

    2013-10-01

    This report presents an unreliability evaluation of the high-pressure core spray (HPCS) at 8 U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2012 for selected components were obtained from the Equipment Performance and Information Exchange (EPIX). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPCS results.

  10. System Study: High-Pressure Core Spray 1998–2013

    SciTech Connect

    Schroeder, John Alton

    2015-01-31

    This report presents an unreliability evaluation of the high-pressure core spray (HPCS) at eight U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2013 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10-year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPCS results.

  11. System Study: Reactor Core Isolation Cooling 1998–2013

    SciTech Connect

    Schroeder, John Alton

    2015-01-31

    This report presents an unreliability evaluation of the reactor core isolation cooling (RCIC) system at 31 U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2013 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10-year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant trends were identified in the RCIC results.

  12. System Study: Reactor Core Isolation Cooling 1998–2012

    SciTech Connect

    T. E. Wierman

    2013-10-01

    This report presents an unreliability evaluation of the reactor core isolation cooling (RCIC) system at 31 U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2012 for selected components were obtained from the Equipment Performance and Information Exchange (EPIX). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing trend was identified in the HPCI results. Statistically significant decreasing trends were identified for RCIC start-only and 8-hour trends.

  13. System Study: Reactor Core Isolation Cooling 1998-2014

    SciTech Connect

    Schroeder, John Alton

    2015-12-01

    This report presents an unreliability evaluation of the reactor core isolation cooling (RCIC) system at 31 U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant trends were identified in the RCIC results.

  14. System Study: High-Pressure Core Spray 1998-2014

    SciTech Connect

    Schroeder, John Alton

    2015-12-01

    This report presents an unreliability evaluation of the high-pressure core spray (HPCS) at eight U.S. commercial boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the HPCS results.

  15. Secondary Social Studies Teachers' Time Commitment When Addressing the Common Core State Standards

    ERIC Educational Resources Information Center

    Kenna, Joshua L.; Russell, William Benedict, III

    2015-01-01

    In 2010 the Common Core State Standards (CCSS) were officially released in America for mathematics and English language arts and soon adopted by 45 of the 50 states. However, within the English langue arts domain there were standards intended for secondary social studies teachers under the title, Common Core State Standards for English Language…

  16. Identifying Core Mobile Learning Faculty Competencies Based Integrated Approach: A Delphi Study

    ERIC Educational Resources Information Center

    Elbarbary, Rafik Said

    2015-01-01

    This study is based on the integrated approach as a concept framework to identify, categorize, and rank a key component of mobile learning core competencies for Egyptian faculty members in higher education. The field investigation framework used four rounds Delphi technique to determine the importance rate of each component of core competencies…

  17. Revisiting Traveling Books: Early Literacy, Social Studies, and the Common Core

    ERIC Educational Resources Information Center

    Swain, Holly Hilboldt; Coleman, Julianne

    2015-01-01

    With the development and institution of the Common Core Standards, teachers must be prepared to integrate content areas such as social studies within the language arts curriculum. Teachers following the suggestions of the Common Core Standards should develop practical and meaningful strategies within their classrooms that encourage and support…

  18. Fluorescence studies of cyanobacterial phycobiliproteins: I. Spectroscopy of allophycocyanin core complexes. II. Spectroscopy of two phycobilisome core insertion mutants

    SciTech Connect

    Maxson, P.

    1988-10-01

    The work described here relates to the mechanisms governing energy transfer in the core polypeptides of the cyanobacterial phycobilisome. Two approaches are represented: measurements were made on isolated core components for which a great deal of structural information is available; and the fluorescence properties were characterized for the whole phycobilisome from two phycobilisome core insertion mutants. 130 refs.

  19. A comprehensive core-phase study from reflected waveform data

    NASA Astrophysics Data System (ADS)

    Li, D.; Schmandt, B.; Sun, D.; Helmberger, D. V.

    2012-12-01

    A recent event beneath central America produced an excellent set of core phases recorded by USArray ranging from 18 to 30 degree. The results from 1D modeling (Schmandt, 2012) indicate that the ratio of PKiKP/PcP is about 0.16 whereas the prediction from the reference model PREM is 0.085. The prediction can match this ratio by adding a weak ULVZ (with -5% in Vp, -10% in Vs, and 5% in density) at the CMB if the top is gradational. The variation in the core-phases ratios involving ScP, ScS, PcP, PKiKP displays considerable scatter with a factor of 4 or more. Here, we investigate this scatter by examining the roles of source directivity, variation in 3D velocity structures and attenuation, and the station site effects. Preliminary waveform complexity measured by the Multi-Path Detector analysis (Sun et.al, 2009) indicates that a small scale variation of the order of 100 to 200km near the CMB is involved. To localize the causes of these fluctuations we generate seismogram using both WKM ray code and numerical code. The former produced ray-path corrected for 2D structure while the latter are more complete. This is achieved by using a staggered grid finite difference with embedded earthquake sources. To reach high frequencies (1Hz) , we use a fine grid size of 0.7 km to reduce the dispersion. A correction account for out of plane spreading is applied as a post processing step.

  20. Cross-calibration of the Landsat-7 ETM+ and Landsat-5 TM with the ResourceSat-1 (IRS-P6) AWiFS and LISS-III sensors

    USGS Publications Warehouse

    Chander, G.; Scaramuzza, P.L.

    2006-01-01

    Increasingly, data from multiple sensors are used to gain a more complete understanding of land surface processes at a variety of scales. The Landsat suite of satellites has collected the longest continuous archive of multispectral data. The ResourceSat-1 Satellite (also called as IRS-P6) was launched into the polar sunsynchronous orbit on Oct 17, 2003. It carries three remote sensing sensors: the High Resolution Linear Imaging Self-Scanner (LISS-IV), Medium Resolution Linear Imaging Self-Scanner (LISS-III), and the Advanced Wide Field Sensor (AWiFS). These three sensors are used together to provide images with different resolution and coverage. To understand the absolute radiometric calibration accuracy of IRS-P6 AWiFS and LISS-III sensors, image pairs from these sensors were compared to the Landsat-5 TM and Landsat-7 ETM+ sensors. The approach involved the calibration of nearly simultaneous surface observations based on image statistics from areas observed simultaneously by the two sensors.

  1. First-principles study of the influence of different interfaces and core types on the properties of CdSe/CdS core-shell nanocrystals

    NASA Astrophysics Data System (ADS)

    Kocevski, V.; Rusz, J.; Eriksson, O.; Sarma, D. D.

    2015-06-01

    With the expanding field of nanoengineering and the production of nanocrystals (NCs) with higher quality and tunable size, having reliable theoretical calculations to complement the experimental results is very important. Here we present such a study of CdSe/CdS core-shell NCs using density functional theory, where we focus on dependence of the properties of these NCs on core types and interfaces between the core and the shell, as well as on the core/shell ratio. We show that the density of states and the absorption indices depend rather weakly on the type of interface and core type. We demonstrate that the HOMO wavefunction is mainly localised in the core of the nanocrystal, depending primarily on the core/shell ratio. On the other hand the LUMO wavefunction spreads more into the shell of the nanocrystal, where its confinement in the core is almost the same in each of the studied structural models. Furthermore, we show that the radiative lifetimes decrease with increasing core sizes due to changes in the dipolar overlap integral of the HOMO and LUMO wavefunctions. In addition, the electron-hole Coulomb interaction energies follow a similar pattern as the localisation of the wavefunctions, with the smaller NCs having higher Coulomb interaction energies.

  2. First-principles study of the influence of different interfaces and core types on the properties of CdSe/CdS core-shell nanocrystals

    PubMed Central

    Kocevski, V.; Rusz, J.; Eriksson, O.; Sarma, D.D.

    2015-01-01

    With the expanding field of nanoengineering and the production of nanocrystals (NCs) with higher quality and tunable size, having reliable theoretical calculations to complement the experimental results is very important. Here we present such a study of CdSe/CdS core-shell NCs using density functional theory, where we focus on dependence of the properties of these NCs on core types and interfaces between the core and the shell, as well as on the core/shell ratio. We show that the density of states and the absorption indices depend rather weakly on the type of interface and core type. We demonstrate that the HOMO wavefunction is mainly localised in the core of the nanocrystal, depending primarily on the core/shell ratio. On the other hand the LUMO wavefunction spreads more into the shell of the nanocrystal, where its confinement in the core is almost the same in each of the studied structural models. Furthermore, we show that the radiative lifetimes decrease with increasing core sizes due to changes in the dipolar overlap integral of the HOMO and LUMO wavefunctions. In addition, the electron-hole Coulomb interaction energies follow a similar pattern as the localisation of the wavefunctions, with the smaller NCs having higher Coulomb interaction energies. PMID:26039582

  3. Switching probabilities of magnetic vortex core reversal studied by table top magneto optic Kerr microscopy

    NASA Astrophysics Data System (ADS)

    Dieterle, G.; Gangwar, A.; Gräfe, J.; Noske, M.; Förster, J.; Woltersdorf, G.; Stoll, H.; Back, C. H.; Schütz, G.

    2016-01-01

    We have studied vortex core reversal in a single submicron Permalloy disk by polar Kerr microscopy. A sophisticated lock-in-technique based on repetitive switching of the magnetic vortex core and a continuous calibration allows for a reliable determination of the switching probability. This highly sensitive method facilitates the detection of a change in the magnetic moment of the tiny magnetic vortex core which is about 1.5 × 10-17 A m2. We have investigated vortex core switching caused by excitation of the vortex core gyromode with varying frequencies and amplitudes. The frequency range in which switching occurs was found to broaden with increasing excitation amplitude, whereby the highest frequency in this range shifts stronger to higher frequencies than the lowest frequency to lower frequencies. The experimental results are in good agreement with micromagnetic simulations.

  4. Experimental study of the mechanical behaviour of pin reinforced foam core sandwich materials under shear load

    NASA Astrophysics Data System (ADS)

    Dimassi, M. A.; Brauner, C.; Herrmann, A. S.

    2016-03-01

    Sandwich structures with a lightweight closed cell hard foam core have the potential to be used in primary structures of commercial aircrafts. Compared to honeycomb core sandwich, the closed cell foam core sandwich overcomes the issue of moisture take up and makes the manufacturing of low priced and highly integrated structures possible. However, lightweight foam core sandwich materials are prone to failure by localised external loads like low velocity impacts. Invisible cracks could grow in the foam core and threaten the integrity of the structure. In order to enhance the out-of-plane properties of foam core sandwich structures and to improve the damage tolerance (DT) dry fibre bundles are inserted in the foam core. The pins are infused with resin and co-cured with the dry fabric face sheets in an out-of-autoclave process. This study presents the results obtained from shear tests following DIN 53294-standard, on flat sandwich panels. All panels were manufactured with pin-reinforcement manufactured with the Tied Foam Core Technology (TFC) developed by Airbus. The effects of pin material (CFRP and GFRP) and pin volume fraction on the shear properties of the sandwich structure and the crack propagation were investigated and compared to a not pinned reference. It has been concluded that the pin volume fraction has a remarkable effect on the shear properties and damage tolerance of the observed structure. Increasing the pin volume fraction makes the effect of crack redirection more obvious and conserves the integrity of the structure after crack occurrence.

  5. Small Angle Neutron-Scattering Studies of the Core Structure of Intact Neurosecretory Vesicles.

    NASA Astrophysics Data System (ADS)

    Krueger, Susan Takacs

    Small angle neutron scattering (SANS) was used to study the state of the dense cores within intact neurosecretory vesicles. These vesicles transport the neurophysin proteins, along with their associated hormones, oxytocin or vasopressin, from the posterior pituitary gland to the bloodstream, where the entire vesicle contents are released. Knowledge of the vesicle core structure is important in developing an understanding of this release mechanism. Since the core constituents exist in a dense state at concentrations which cannot be reproduced (in solution) in the laboratory, a new method was developed to determine the core structure from SANS experiments performed on intact neurosecretory vesicles. These studies were complemented by biochemical assays performed to determine the role, if any, played by phospholipids in the interactions between the core constituents. H_2O/D_2 O ratio in the solvent can be adjusted, using the method of contrast variation, such that the scattering due to the vesicle membranes is minimized, thus emphasizing the scattering originating from the cores. The applicability of this method for examining the interior of biological vesicles was tested by performing an initial study on human red blood cells, which are similar in structure to other biological vesicles. Changes in intermolecular hemoglobin interactions, occurring when the ionic strength of the solvent was varied or when the cells were deoxygenated, were examined. The results agreed with those expected for dense protein solutions, indicating that the method developed was suitable for the study of hemoglobin within the cells. Similar SANS studies were then performed on intact neurosecretory vesicles. The experimental results were inconsistent with model calculations which assumed that the cores consisted of small, densely-packed particles or large, globular aggregates. Although a unique model could not be determined, the data suggest that the core constituents form long aggregates of

  6. Study of photodynamic activity of Au@SiO2 core-shell nanoparticles in vitro.

    PubMed

    Meena, K S; Dhanalekshmi, K I; Jayamoorthy, K

    2016-06-01

    Metal-semiconductor core-shell type Au@SiO2 nanoparticles were prepared by Stober's method. They were characterized by absorption, XRD, HR-TEM and EDAX techniques. The resulting modified core-shell nanoparticles shows that the formation of singlet oxygen, which was confirmed by ESR technique. The photohemolysis studies were carried out under two different experimental conditions. It is observed that the photohemolysis increases with concentration as well as light dose. Cell viability of the core-shell nanoparticles against HeLa cell lines were studied by MTT assay method. The outcomes of the present study indicate that, the Au@SiO2 core-shell nanoparticles are extremely stable with a very high photodynamic efficiency under visible light illumination. PMID:27040225

  7. Study of the F ring core at high and low resolutions with Cassini ISS

    NASA Astrophysics Data System (ADS)

    Deau, Estelle

    2014-11-01

    Saturn’s F ring evolution is still a mystery since its discovery by Pioneer 11. This ring is unique by its changing appearance, its spiral shape, its shepherd satellites Prometheus and Pandora, its ephemeral satellites, and its chaotic behavior. We focus here on the brightest and central region of the F ring called the core. Using Voyager data, the core was primarily believed to be one of the four strands of the F ring (Murray et al., 1997, Icarus, vol.129, p.304-316). However, the core is very different from the other stands, because we have demonstrated previously that the core reconnects on itself over 360 degrees, while the strands don't (Charnoz et al. 2005, Science, vol.310, p.1300-1304). Indeed, the strands originate from the core and are connected between themselves in a single feature that is a spiral, as explained in our previous works (Charnoz et al. 2005, Science, vol.310, p.1300-1304, Deau, 2007, PhD thesis University Paris 7 Denis Diderot). Our present study focus on the F ring core. We have established a protocol in (Deau, 2007, PhD thesis University Paris 7 Denis Diderot) to calculate the radial width and the radial local variations of the core using a Gaussian model. We use this method on Cassini ISS data to derive azimuthal profiles of core's radial width and local kicks. Our study shows that the F ring core is very stable on scale of several months, as suggested by the recent chaos theory of Cuzzi et al. (2014, Icarus, vol.232, p.157-175), while the spiral has a much smaller timescale, i.e. the order of a few weeks.

  8. Time-resolved SANS studies on block copolymer micelles with varying core-solvent interactions

    NASA Astrophysics Data System (ADS)

    Cooksey, Tyler; Singh, Avantika; Marquez, Maria; Robertson, Megan

    The self-assembly of block copolymer micelles occurs through a relaxation process dominated by the exchange of individual polymer chains. The objective of this work is to probe the single chain exchange of block copolymer micelles with varying core-solvent interactions, utilizing time-resolved neutron scattering (TR-SANS). The interactions between the core-forming polymer and the solvent has many implications for the micelle structure, including the aggregation number, micelle size, and interfacial tension. However, few studies have investigated the effect of the core polymer-solvent interactions on the dynamics of micelle formation. We will focus our study on poly(epsilon-caprolactone-block-ethylene oxide) block copolymers forming micelle structures in mixtures of water and tetrahydrofuran (THF). It was observed that changing the THF concentration, which varies the degree of repulsion between the core and solvent, greatly influences the single chain exchange rate in this system.

  9. Star formation in Chamaeleon I and III: a molecular line study of the starless core population

    NASA Astrophysics Data System (ADS)

    Tsitali, A. E.; Belloche, A.; Garrod, R. T.; Parise, B.; Menten, K. M.

    2015-03-01

    Context. The Chamaeleon dark molecular clouds are excellent nearby targets for low-mass star formation studies. Even though they belong to the same cloud complex, Cha I and II are actively forming stars while Cha III shows no sign of ongoing star formation. Aims: We aim to determine the driving factors that have led to the very different levels of star formation activity in Cha I and III and examine the dynamical state and possible evolution of the starless cores within them. Methods: Observations were performed in various molecular transitions with the APEX and Mopra telescopes. We examine the kinematics of the starless cores in the clouds through a virial analysis, a search for contraction motions, and velocity gradients. The chemical differences in the two clouds are explored through their fractional molecular abundances, derived from a non-LTE analysis, and comparison to predictions of chemical models. Results: Five cores are gravitationally bound in Cha I and one in Cha III. The so-called infall signature indicating contraction motions is seen toward 8-17 cores in Cha I and 2-5 cores in Cha III, which leads to a range of 13-28% of the cores in Cha I and 10-25% of the cores in Cha III that are contracting and may become prestellar. There is no significant difference in the turbulence level in the two clouds. Future dynamical interactions between the cores will not be dynamically significant in either Cha I or III, but the subregion Cha I North may experience collisions between cores within ~0.7 Myr. Turbulence dissipation in the cores of both clouds is seen in the high-density tracers N2H+ 1-0 and HC3N 10-9 which have lower non-thermal velocity dispersions compared to C17O 2-1, C18O 2-1, and C34S 2-1. Evidence of depletion in the Cha I core interiors is seen in the abundance distributions of the latter three molecules. The median fractional abundance of C18O is lower in Cha III than Cha I by a factor of ~2. The median abundances of most molecules (except

  10. Nondestructive observation of teeth post core space using optical coherence tomography: a pilot study.

    PubMed

    Minamino, Takuya; Mine, Atsushi; Omiya, Kouta; Matsumoto, Mariko; Nakatani, Hayaki; Iwashita, Taichi; Ohmi, Masato; Awazu, Kunio; Yatani, Hirofumi

    2014-04-01

    Coronal tooth lesions, such as caries, enamel cracking, and composite resin restoration cavities, have been observed by optical coherence tomography (OCT). This pilot study was performed to verify whether OCT could reveal details of root canals filled with resin core build-up. A dual-cure, one-step, self-etch adhesive system-bonding agent (Clearfil Bond SE ONE, Kuraray Noritake Dental) and dual-cure resin composite core material (Clearfil DC Core Automix ONE, Kuraray Noritake Dental) were used according to the manufacturer's instructions in root canals. OCT was performed at three stages of the core build-up: after the post space preparation, after bonding application, and after resin core fabrication. The cementum was removed in the cementum absent group and the root was left untreated in the cementum present group. Bubbles were observed in the resin cores and gaps formed between the resin core and dentin. In the cementum absent group, the internal structure of the root could be visualized clearly compared with the cementum present group. The root internal structure could be observed by OCT and the image became clearer when cementum was removed. PMID:24711153

  11. Initial Studies of Core and Edge Transport of NSTX Plasmas

    SciTech Connect

    E.J. Synakowski; M.G. Bell; R.E. Bell; C.E. Bush; C. Bourdelle; D. Darrow; W. Dorland; A. Ejiri; E.D. Fredrickson; D.A. Gates; S.M. Kaye; S. Kubota; H.W. Kugel; B.P. LeBlanc; R. Maingi; R.J. Maqueda; J.E. Menard; D. Mueller; A. Rosenberg; S.A. Sabbagh; D. Stutman; G. Taylor; D.W. Johnson; R. Kaita; M. Ono; F. Paoletti; W. Peebles; Y-K.M. Peng; A.L. Roquemore , C.H. Skinner; V.A. Soukhanovskii; and the NSTX Research Team

    2001-09-19

    Rapidly developing diagnostic, operational, and analysis capability is enabling the first detailed local physics studies to begin in high-beta plasmas of the National Spherical Torus Experiment (NSTX). These studies are motivated in part by energy confinement times in neutral-beam-heated discharges that are favorable with respect to predictions from the ITER-89P scaling expression. Analysis of heat fluxes based on profile measurements with neutral-beam injection (NBI) suggest that the ion thermal transport may be exceptionally low, and that electron thermal transport is the dominant loss channel. This analysis motivates studies of possible sources of ion heating not presently accounted for by classical collisional processes. Gyrokinetic microstability studies indicate that long wavelength turbulence with k(subscript ''theta'') rho(subscript ''i'') {approx} 0.1-1 may be suppressed in these plasmas, while modes with k(subscript ''theta'') rho(subscript ''i'') {approx} 50 may be robust. High-harmonic fast-wave (HHFW) heating efficiently heats electrons on NSTX, and studies have begun using it to assess transport in the electron channel. Regarding edge transport, H-mode [high-confinement mode] transitions occur with either NBI or HHFW heating. The power required for low-confinement mode (L-mode) to H-mode transitions far exceeds that expected from empirical edge-localized-mode-free H-mode scaling laws derived from moderate aspect ratio devices. Finally, initial fluctuation measurements made with two techniques are permitting the first characterizations of edge turbulence.

  12. Study of core-shell platinum-based catalyst for methanol and ethylene glycol oxidation

    NASA Astrophysics Data System (ADS)

    Kaplan, D.; Alon, M.; Burstein, L.; Rosenberg, Yu.; Peled, E.

    A Ru core-Pt shell, XC72-supported catalyst was synthesized in a two-step process: first, by deposition of Ru on XC72 by the polyol process and then by deposition of Pt on the XC72-supported Ru, with NaBH 4 as reducing agent. The structure and composition of this core-shell catalyst were determined by EDS, XPS, TEM and XRD. Electrochemical characterization was determined with the use of cyclic voltammetry and chronoamperometry. The methanol and ethylene glycol oxidation activities of the core-shell catalyst were studied at 80 °C and compared to those of a commercial catalyst. It was found to be significantly better (in terms of A g -1 of Pt) in the case of methanol oxidation and worse in the case of ethylene glycol oxidation. Possible reasons for the lower ethylene glycol oxidation activity of the core-shell catalyst are discussed.

  13. Magnetic studies of erosion in a Scottish lake catchment. 1. Core chronology and correlation

    SciTech Connect

    Appleby, P.G.; Dearing J.A.; Oldfield, F.

    1985-11-01

    Magnetic susceptibility, /sup 210/Pb, /sup 137/Cs, /sup 14/C, and paleomagnetic secular variation are used to establish the chronology of sedimentation in a set of cores from Loch Frisa in western Scotland. The /sup 14/C dates obtained are not compatible with the chronology derived from all the other techniques and this is ascribed to inwash of old particulate carbon from the watershed. Central cores show little evidence of changes in sedimentation rate over the last 150 years whereas marginal cores contain evidence of major increases arising from ploughing and from drainage associated with catchment afforestation since 1935. The results illustrate the value of a multiple core approach to sedimentation and erosion studies even where complex lake morphometry precludes calculation of sediment budgets.

  14. Core and Refueling Design Studies for the Advanced High Temperature Reactor

    SciTech Connect

    Holcomb, David Eugene; Ilas, Dan; Varma, Venugopal Koikal; Cisneros, Anselmo T; Kelly, Ryan P; Gehin, Jess C

    2011-09-01

    The Advanced High Temperature Reactor (AHTR) is a design concept for a central generating station type [3400 MW(t)] fluoride-salt-cooled high-temperature reactor (FHR). The overall goal of the AHTR development program is to demonstrate the technical feasibility of FHRs as low-cost, large-size power producers while maintaining full passive safety. This report presents the current status of ongoing design studies of the core, in-vessel structures, and refueling options for the AHTR. The AHTR design remains at the notional level of maturity as important material, structural, neutronic, and hydraulic issues remain to be addressed. The present design space exploration, however, indicates that reasonable options exist for the AHTR core, primary heat transport path, and fuel cycle provided that materials and systems technologies develop as anticipated. An illustration of the current AHTR core, reactor vessel, and nearby structures is shown in Fig. ES1. The AHTR core design concept is based upon 252 hexagonal, plate fuel assemblies configured to form a roughly cylindrical core. The core has a fueled height of 5.5 m with 25 cm of reflector above and below the core. The fuel assembly hexagons are {approx}45 cm across the flats. Each fuel assembly contains 18 plates that are 23.9 cm wide and 2.55 cm thick. The reactor vessel has an exterior diameter of 10.48 m and a height of 17.7 m. A row of replaceable graphite reflector prismatic blocks surrounds the core radially. A more complete reactor configuration description is provided in Section 2 of this report. The AHTR core design space exploration was performed under a set of constraints. Only low enrichment (<20%) uranium fuel was considered. The coated particle fuel and matrix materials were derived from those being developed and demonstrated under the Department of Energy Office of Nuclear Energy (DOE-NE) advanced gas reactor program. The coated particle volumetric packing fraction was restricted to at most 40%. The pressure

  15. Cycle 0(CY1991) NLS trade studies and analyses report. Book 1: Structures and core vehicle

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This report (SR-1: Structures, Trades, and Analysis), documents the Core Tankage Trades and analyses performed in support of the National Launch System (NLS) Cycle 0 preliminary design activities. The report covers trades that were conducted on the Vehicle Assembly, Fwd Skirt, LO2 Tank, Intertank, LH2 Tank, and Aft Skirt of the NLS Core Tankage. For each trade study, a two page executive summary and the detail trade study are provided. The trade studies contain study results, recommended changes to the Cycle 0 Baselines, and suggested follow on tasks to be performed during Cycle 1.

  16. A Global Study of Inner Core Boundary Topography and its Temporal Variations

    NASA Astrophysics Data System (ADS)

    Ibourichene, A.; Romanowicz, B. A.

    2015-12-01

    The inner core boundary (ICB) separates the solid inner core from the surrounding liquid outer core. Its detailed properties, such as its shape, the density jump across it or its topography are key for understanding the dynamics of the core and, ultimately, the generation and sustained character of the Earth's magnetic field. The determination of the ICB topography and its variation with time could also enhance our understanding of the inner core growth and its past history.Seismology makes use of two phases to study the shallow inner core : the PKiKP, reflected at the ICB and the PKIKP, refracted into the inner core. The PKiKP/PKIKP amplitude ratio and the travel time residual of these phases characterize the vicinity of the ICB and may help constrain ICB topography. Different studies propose various wavelengths for this topography: from hundreds of meters to tens of kilometers. Several parameters can affect PKiKP/PKIKP amplitude ratios and the corresponding differential travel time, such as the quality factor of the shallow inner core, the density jump at the ICB, the geometry of the ray paths or even the reflection coefficient at the ICB. We present a global map of PKiKP/PKIKP amplitude ratios and differential travel times filtered in different pass-bands, with regional densification based, in particular, on the relatively short wavelength sampling afforded by large aperture broadband arrays, such as USArray, and discuss their spatial variability and interpretation in terms of ICB topography, as appropriate.We also have assembled a catalog of high quality doublets which provide a reference for the stability of the measurements, and point to possible time variability of the topography.

  17. Relationship of Core Self-Evaluation (CSE) to Approaches to Student Learning and Studying

    ERIC Educational Resources Information Center

    Starcher, Keith

    2015-01-01

    Insights on the use of the Core Self-Evaluation (CSE) and Study Process Questionnaire (SPQ) instruments are presented. The relationship of students' CSE with their approach to studying and learning is explored. Differences in approach to studying are also analyzed based on several categorical variables.

  18. A study on reactor core failure thresholds to safety operation of LMFBR

    SciTech Connect

    Kazuo, Haga; Hiroshi, Endo; Tomoko, Ishizu; Yoshihisa, Shindo

    2006-07-01

    Japan Nuclear Safety Organization (JNES) has been developing the methodology and computer codes for applying level-1 PSA to LMFBR. Many of our efforts have been directed to the judging conditions of reactor core damage and the time allowed to initiate the accident management. Several candidates of the reactor core failure threshold were examined to a typical proto-type LMFBR with MOX fuel based on the plant thermal-hydraulic analyses to the actual progressions leading to the core damage. The results of the present study showed that the judging condition of coolant-boundary integrity failure, 750 degree-C of the boundary temperature, is enough as the threshold of core damage to PLOHS (protected loss-of-heat sink). High-temperature fuel cladding creep failure will not take place before the coolant-boundary reaches the judging temperature and sodium boiling will not occur due to the system pressure rise. In cases of ATWS (anticipated transient without scrum) the accident progression is so fast and the reactor core damage will be inevitable even a realistic negative reactivity insertion due to the temperature rise is considered. Only in the case of ULOHS (unprotected loss-of-heat sink) a relatively long time of 11 min will be allowed till the shut-down of the reactor before the core damage. (authors)

  19. A study of the structural efficiency of fluted core graphite-epoxy panels

    NASA Technical Reports Server (NTRS)

    Jegley, Dawn C.

    1990-01-01

    The structural efficiency of compression-loaded graphite-epoxy sandwich panels with fluted cores is studied to determine their weight saving potential. Graphite-epoxy equilateral triangular elements are used to construct the fluted cores for the sandwich panels. Two panel configurations are considered. One configuration has two layers of triangular elements in the fluted core and the second configuration has only one layer of triangular elements in the core. An optimization code is used to find the minimum weight design for each panel configuration. Laminate ply orientations are limited to approx. 45, 0, and 90 deg. A constraint on the axial stiffness is included in the design process so the panel will conform to typical constraints for aircraft wing structures. Minimum thickness requirements for each laminate and maximum allowable strains are also included. A comparison is made of the calculated structural efficiency of the fluted core panels to the structural efficiency of aluminum transport aircraft structures and simple blade-stiffened graphite-epoxy panels. Limited experimental results are also included for comparison with the analytical predictions and to identify the critical failure mechanisms of graphite-epoxy fluted-core sandwich panels.

  20. The paleoclimatic and geochronologic utility of coring red beds and evaporites: a case study from the RKB core (Permian, Kansas, USA)

    NASA Astrophysics Data System (ADS)

    Soreghan, Gerilyn S.; Benison, Kathleen C.; Foster, Tyler M.; Zambito, Jay; Soreghan, Michael J.

    2015-09-01

    Drill core is critical for robust and high-resolution reconstructions of Earth's climate record, as well demonstrated from both marine successions and modern long-lived lake systems. Deep-time climate reconstructions increasingly require core-based data, but some facies, notably red beds and evaporites, have garnered less attention for both paleoclimatic and geochronologic analyses. Here, we highlight studies from the Rebecca K. Bounds (RKB) core, a nearly continuous, >1.6 km drill core extending from the Cretaceous to the Mississippian, recovered from the US Midcontinent by Amoco Production Company in 1988, and serendipitously made available for academic research. Recent research conducted on this core illustrates the potential to recover high-resolution data for geochronologic and climatic reconstructions from both the fine-grained red bed strata, which largely represent paleo-loess deposits, and associated evaporite strata. In this case, availability of core was instrumental for (1) accessing a continuous vertical section that establishes unambiguous superposition key to both magnetostratigraphic and paleoclimatic analyses, and (2) providing pristine sample material from friable, soluble, and/or lithofacies and mineralogical species otherwise poorly preserved in surface exposures. The potential for high-resolution paleoclimatic reconstruction from coring of deep-time loess strata in particular remains severely underutilized.

  1. Study on Ultra-Long Life,Small U-Zr Metallic Fuelled Core With Burnable Poison

    SciTech Connect

    Kenji Tsuji; Hiromitsu Inagaki; Akira Nishikawa; Hisato Matsumiya; Yoshiaki Sakashita; Yasuyuki Moriki; Mitsuaki Yamaoka; Norihiko Handa

    2002-07-01

    A conceptual design for a 50 MWe sodium cooled, U-Pu-Zr metallic fuelled, fast reactor core, which aims at a core lifetime of 30 years, has been performed [1]. As for the compensation for a large burn-up reactivity through 30 years, an axially movable reflector, which is located around the core, carries the major part of it and a burnable poison does the rest. This concept has achieved not only a long core lifetime but also a high discharged burn-up. On this study, a conceptual design for a small fast reactor loading U-Zr metallic fuelled core instead of U-Pu-Zr fuelled core has been conducted, based on the original core arrangement of 4S reactor [2]. Within the range of this study including safety requirements, adopting the burnable poison would be effective to construct a core concept that achieves both a long lifetime and a high discharged burn-up. (authors)

  2. High School Teachers' Perspectives on the English Language Arts Common Core State Standards: An Exploratory Study

    ERIC Educational Resources Information Center

    Ajayi, Lasisi

    2016-01-01

    This was an exploratory study that examined high school teachers' perspectives about their early experiences with the English language arts Common Core State Standards. The sources of data for the study included a survey and structured interviews. Twenty-three high school ELA teachers from one unified school district in Southern California…

  3. A Chandra Study of the Image Power Spectra of 41 Cool Core and Non-cool Core Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Zhang, Chenhao; Xu, Haiguang; Zhu, Zhenghao; Li, Weitian; Hu, Dan; Wang, Jingying; Gu, Junhua; Gu, Liyi; Zhang, Zhongli; Liu, Chengze; Zhu, Jie; Wu, Xiang-Ping

    2016-06-01

    In this work we propose a new diagnostic to segregate cool core (CC) clusters from non-CC (NCC) clusters by studying the two-dimensional power spectra of the X-ray images observed with the Chandra X-ray observatory. Our sample contains 41 members (z=0.01{--}0.54) which are selected from the Chandra archive when a high photon count, an adequate angular resolution, a relatively complete detector coverage, and coincident CC–NCC classifications derived with three traditional diagnostics are simultaneously guaranteed. We find that in the log–log space the derived image power spectra can be well represented by a constant model component at large wavenumbers, while at small wavenumbers a power excess beyond the constant component appears in all clusters, with a clear tendency that the excess is stronger in CC clusters. By introducing a new CC diagnostic parameter, i.e., the power excess index (PEI), we classify the clusters in our sample and compare the results with those obtained with three traditional CC diagnostics. We find that the results agree with each other very well. By calculating the PEI values of the simulated clusters, we find that the new diagnostic works well at redshifts up to 0.5 for intermediately sized and massive clusters with a typical Chandra or XMM-Newton pointing observation. The new CC diagnostic has several advantages over its counterparts, e.g., it is free of the effects of the commonly seen centroid shift of the X-ray halo caused by merger event, and the corresponding calculation is straightforward, almost irrelevant to the complicated spectral analysis.

  4. Studies of mixed HEU-LEU-MTR cores using 3D models

    SciTech Connect

    Haenggi, P.; Lehmann, E.; Hammer, J.; Christen, R.

    1997-08-01

    Several different core loadings were assembled at the SAPHIR research reactor in Switzerland combining the available types of MTR-type fuel elements, consisting mainly of both HEU and LEU fuel. Bearing in mind the well known problems which can occur in such configurations (especially power peaking), investigations have been carried out for each new loading with a 2D neutron transport code (BOXER). The axial effects were approximated by a global buckling value and therefore the radial effects could be studied in considerably detail. Some of the results were reported at earlier RERTR meetings and were compared to those obtained by other methods and with experimental values. For the explicit study of the third dimension of the core, another code (SILWER), which has been developed in PSI for LWR power plant cores, has been selected. With the help of an adapted model for the MTR-core of SAPHIR, several important questions have been addressed. Among other aspects, the estimation of the axial contribution to the hot channel factors, the influence of the control rod position and of the Xe-poisoning on the power distribution were studied. Special attention was given to a core position where a new element was assumed placed near a empty, water filled position. The comparison of elements of low and high enrichments at this position was made in terms of the induced power peaks, with explicit consideration of axial effects. The program SILWER has proven to be applicable to MTR-cores for the investigation of axial effects. For routine use as for the support of reactor operation, this 3D code is a good supplement to the standard 2D model.

  5. Experimental Study on the Performance of IIST Passive Core Cooling System

    SciTech Connect

    Chin-Jang Chang; Chien-Hsiung Lee; Wen-Tan Hong; Wang, Lance L.C.

    2002-07-01

    The purpose of this study is to conduct the experiments at the Institute of Nuclear Energy Research (INER) Integral System Test (IIST) facility for evaluation of the performance of the passive core cooling system (PCCS) during the cold-leg small break loss-of-coolant accidents (SBLOCAs). Five experiments were performed with (1) three different break sizes, 2%, 0.5%, and 0.2% (approximately corresponding to 1 1/4'', 2'', and 4'' breaks for Maanshan nuclear power plant), and (2) 0.2% and 0.5% without actuation of the first-stage and third-stage automatic depressurization valve (ADS-1 and ADS-3) to initiate PCCS for assessing its capacity in accident management. The detailed descriptions of general system response and the interactions of core makeup tanks (CMTs), accumulators (ACCs), automatic depressurization system (ADS), passive residual heat Removal (PRHR), and in-containment refueling water storage tank (IRWST) on the core heat removal are included. The results show: (1) core long term cooling can be maintained for all cases following the PCCS procedures, (2) the core can be covered for the cases of the 0.2% and 0.5% breaks without actuation of ADS-1 and ADS-3. (authors)

  6. Experimental Study of the Compression Response of Fluted-Core Composite Panels with Joints

    NASA Technical Reports Server (NTRS)

    Schultz, Marc R.; Rose, Cheryl A.; Guzman, J. Carlos; McCarville, Douglas; Hilburger, Mark W.

    2012-01-01

    Fluted-core sandwich composites consist of integral angled web members spaced between laminate face sheets, and may have the potential to provide benefits over traditional sandwich composites for certain aerospace applications. However, fabrication of large autoclave-cured fluted-core cylindrical shells with existing autoclaves will require that the shells be fabricated in segments, and joined longitudinally to form a complete barrel. Two different longitudinal fluted-core joint designs were considered experimentally in this study. In particular, jointed fluted-core-composite panels were tested in longitudinal compression because longitudinal compression is the primary loading condition in dry launch-vehicle barrel sections. One of the joint designs performed well in comparison with unjointed test articles, and the other joint design failed at loads approximately 14% lower than unjointed test articles. The compression-after-impact (CAI) performance of jointed fluted-core composites was also investigated by testing test articles that had been subjected to 6 ft-lb impacts. It was found that such impacts reduced the load-carrying capability by 9% to 40%. This reduction is dependent on the joint concept, component flute size, and facesheet thickness.

  7. Flow visualization studies of the cores of thin vortex rings in water

    NASA Astrophysics Data System (ADS)

    Sullivan, Ian; Niemela, Joseph; Donnelly, Russell

    2002-11-01

    We have been studying the propagation of thin core vortex rings in water with the aim of trying to describe them in considerable detail by simple equations. A major problem has been to measure the core radius by some means. Saffman has proposed a relationship for the velocity of vortex rings in a viscous fluid in which the core parameter is the square root of the product of kinematic viscosity and time, where time is measured from some virtual origin. We have decided to take the relevant time as the stroke time for the piston creating the rings. We visualize our rings using the Baker Ph technique where the flow pattern is marked by thymol blue. We pass a laser beam through the ring as it passes and use a photocell to detect the transmitted intensity. We find a dip in intensity as the rings passes, and a distinctive notch in the center of the distribution which we take to be a measure of the core itself. Measurements show that the measured core size agrees reasonably well with Saffman's formula,scales properly with piston stroke time, and is independent of stroke length.

  8. Motivation to Study Core French: Comparing Recent Immigrants and Canadian-Born Secondary School Students

    ERIC Educational Resources Information Center

    Mady, Callie J.

    2010-01-01

    As the number of Allophone students attending public schools in Canada continues to increase (Statistics Canada, 2008), it is clear that a need exists in English-dominant areas to purposefully address the integration of these students into core French. I report the findings of a mixed-method study that was conducted to assess and compare the…

  9. Studies of Medical Students' Activities on Core Surgical Clerkships: A Preliminary Report.

    ERIC Educational Resources Information Center

    Kennedy, W. Robert; Wile, Marcia Z.

    The core surgical clerkship is described as the most intensive clinical experience during the student's first three years, and one which is extremely difficult to examine systematically. The research strategy, methodologies, data collected, and major findings of a study of such clerkships are reported. The data from more than 1000 hours of…

  10. Synthetic Study of Pactamycin: Enantioselective Construction of the Pactamycin Core with Five Contiguous Stereocenters.

    PubMed

    Yamaguchi, Mami; Hayashi, Minami; Hamada, Yasumasa; Nemoto, Tetsuhiro

    2016-05-20

    A synthetic study of pactamycin is described. Enantioselective construction of the aminocyclopentitol core of pactamycin bearing five contiguous stereocenters was achieved based on an organocatalytic asymmetric aziridination of 2-cyclopentene-1-one, a regio- and diastereoselective 1,3-dipolar cycloaddition, and a rhodium-catalyzed C-H amination reaction. PMID:27171747

  11. History as the Core of the Precollege Social Studies Curriculum. A Statement of Policy.

    ERIC Educational Resources Information Center

    Organization of History Teachers, Chicago, IL.

    This policy statement by a national professional association of history teachers from kindergarten through grade 12 begins by pointing out that history currently functions as the core of the social studies curriculum prior to college. This position should be expanded and enhanced as a matter of sound curriculum policy. History alone of the social…

  12. Evaluation of Core Vocabulary Therapy for Deaf Children: Four Treatment Case Studies

    ERIC Educational Resources Information Center

    Herman, Rosalind; Ford, Katie; Thomas, Jane; Oyebade, Natalie; Bennett, Danita; Dodd, Barbara

    2015-01-01

    This study evaluated whether core vocabulary intervention (CVT) improved single word speech accuracy, consistency and intelligibility in four 9-11-year-old children with profound sensori-neural deafness fitted with cochlear implants and/or digital hearing aids. Their speech was characterized by inconsistent production of different error forms for…

  13. Reframing a Social Studies Methods Course: Preparing Elementary Teacher Candidates for the Common Core

    ERIC Educational Resources Information Center

    Gleeson, Ann Marie; D'Souza, Lisa Andries

    2016-01-01

    The emphasis on disciplinary literacy skills embedded within the Common Core State Standards requires a shift in preparing teachers to explicitly address the craft of reading and writing within social studies instruction. As teacher educators, we think it is imperative to understand the ways in which our teacher candidates integrate literacy…

  14. Contents of a Core Library in Continuing Medical Education: A Delphi Study

    ERIC Educational Resources Information Center

    Olson, Curtis A.; Tooman, Tricia R.; Leist, James C.

    2005-01-01

    Introduction: In developing their professional competence, those who are interested in the practice of continuing medical education (CME) should recognize the knowledge base that defines their field. This study systematically identifies and organizes a list of books and journals comprising a core library (100 books/15 journals) for CME…

  15. A Pilot Study of Core Topics in Introductory Social Psychology and Developmental Psychology Textbooks

    ERIC Educational Resources Information Center

    Whitehead, George I., III; Smith, Stephanie H.; Losonczy-Marshall, Marta

    2014-01-01

    This study examined the similarities and differences in the topics and references in selected chapters of eight introductory social psychology textbooks and six developmental psychology textbooks. We wanted to determine the extent to which there were core concepts and references presented in these chapters. We found a relatively small set of core…

  16. Design Core Commonalities: A Study of the College of Design at Iowa State University

    ERIC Educational Resources Information Center

    Venes, Jane

    2015-01-01

    This comprehensive study asks what a group of rather diverse disciplines have in common. It involves a cross-disciplinary examination of an entire college, the College of Design at Iowa State University. This research was intended to provide a sense of direction in developing and assessing possible core content. The reasoning was that material…

  17. Core Competencies: The Challenge for Graduate Peace and Conflict Studies Education

    ERIC Educational Resources Information Center

    Windmueller, John; Wayne, Ellen Kabcenell; Botes, Johannes

    2009-01-01

    This article uses a case study of the assessment of a graduate program in negotiations and conflict management as a springboard for discussing several critical, but unanswered questions in our field. It raises questions regarding the lack of clear core competencies and expectations regarding curricula at the graduate-level of peace and conflict…

  18. Correction of interstitial water changes in calibration methods applied to XRF core-scanning major elements in long sediment cores: Case study from the South China Sea

    NASA Astrophysics Data System (ADS)

    Chen, Quan; Kissel, Catherine; Govin, Aline; Liu, Zhifei; Xie, Xin

    2016-05-01

    Fast and nondestructive X-ray fluorescence (XRF) core scanning provides high-resolution element data that are widely used in paleoclimate studies. However, various matrix and specimen effects prevent the use of semiquantitative raw XRF core-scanning intensities for robust paleoenvironmental interpretations. We present here a case study of a 50.8 m-long piston Core MD12-3432 retrieved from the northern South China Sea. The absorption effect of interstitial water is identified as the major source of deviations between XRF core-scanning intensities and measured element concentrations. The existing two calibration methods, i.e., normalized median-scaled calibration (NMS) and multivariate log-ratio calibration (MLC), are tested with this sequence after the application of water absorption correction. The results indicate that an improvement is still required to appropriately correct the influence of downcore changes in interstitial water content in the long sediment core. Consequently, we implement a new polynomial water content correction in NMS and MLC methods, referred as NPS and P_MLC calibrations. Results calibrated by these two improved methods indicate that the influence of downcore water content changes is now appropriately corrected. We therefore recommend either of the two methods to be applied for robust paleoenvironmental interpretations of major elements measured by XRF-scanning in long sediment sequences with significant downcore interstitial water content changes.

  19. Cadmium Telluride, Cadmium Telluride/Cadmium Sulfide Core/Shell, and Cadmium Telluride/Cadmium Sulfide/Zinc Sulfide Core/Shell/Shell Quantum Dots Study

    NASA Astrophysics Data System (ADS)

    Yan, Yueran

    aqueous phase can quench CdTe/CdS QDs. Additionally, the stability of the different ligands capped CdTe/CdS QDs was tested by dialysis measurement, the hydrodynamic diameters of CdTe and CdTe/CdS core/shell QDs were measured by dynamic light scattering, and dissolving issue was found when CdTe and CdTe/CdS core/shell QDs were diluted in CHCl3. We have characterized the CdTe core and the CdTe/CdS core/shell QDs by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), small angle X-ray scattering (SAXS), and ICP-OES measurements. We have found that the CdTe core was of a zincblende structure, and the shell was a wurtzite structure. And the CdTe/CdS QDs were core/shell QDs instead of alloying QDs. We have also analyzed the photophysical properties of CdTe and CdTe/CdS core/shell QDs. Time-resolved photoluminescence (PL) measurements showed the emission decay lifetimes in the tens of nanoseconds. Additionally, ultrafast charge carrier relaxation dynamics of the CdTe core and CdTe/CdS core/shell QDs were studied by the femtosecond transient absorption (TA) spectroscopy. The transient absorption spectra of CdTe and CdTe/CdS core/shell QDs showed multiple bleaches, which have been assigned to the 1S3/2(h)-1S(e), 2S3/2(h)-1S(e), and 1P3/2(h)-1P(e) transitions. The spectral shifts of these bleaches after shell deposition have been analyzed in the context of a quasi-type-II carrier distribution in the core/shell samples, and interestingly the red shift was only contributed from the conduction band energy levels shifting to lower energy. In addition, the ultrafast evolution of these bleach features has been examined to extract electron cooling rates in these samples. A fast decay component in the 1S3/2(h)-1S(e) transition of the small CdTe QDs was discovered due to the hole being trapped by the defects on the surface of QD. Further, we have studied the PL quenching process of the air exposed CdTe QDs via the PL decay and transient absorption measurements. Oxygen

  20. Charge separation and energy transfer in the photosystem II core complex studied by femtosecond midinfrared spectroscopy.

    PubMed

    Pawlowicz, N P; Groot, M-L; van Stokkum, I H M; Breton, J; van Grondelle, R

    2007-10-15

    The core of photosystem II (PSII) of green plants contains the reaction center (RC) proteins D1D2-cytb559 and two core antennas CP43 and CP47. We have used time-resolved visible pump/midinfrared probe spectroscopy in the region between 1600 and 1800 cm(-1) to study the energy transfer and charge separation events within PSII cores. The absorption difference spectra in the region of the keto and ester chlorophyll modes show spectral evolution with time constants of 3 ps, 27 ps, 200 ps, and 2 ns. Comparison of infrared (IR) difference spectra obtained for the isolated antennas CP43 and CP47 and the D1D2-RC with those measured for the PSII core allowed us to identify the features specific for each of the PSII core components. From the presence of the CP43 and CP47 specific features in the spectra up to time delays of 20-30 ps, we conclude that the main part of the energy transfer from the antennas to the RC occurs on this timescale. Direct excitation of the pigments in the RC evolution associated difference spectra to radical pair formation of PD1+PheoD1- on the same timescale as multi-excitation annihilation and excited state equilibration within the antennas CP43 and CP47, which occur within approximately 1-3 ps. The formation of the earlier radical pair ChlD1+PheoD1-, as identified in isolated D1D2 complexes with time-resolved mid-IR spectroscopy is not observed in the current data, probably because of its relatively low concentration. Relaxation of the state PD1+PheoD1-, caused by a drop in free energy, occurs in 200 ps in closed cores. We conclude that the kinetic model proposed earlier for the energy and electron transfer dynamics within the D1D2-RC, plus two slowly energy-transferring antennas C43 and CP47 explain the complex excited state and charge separation dynamics in the PSII core very well. We further show that the time-resolved IR-difference spectrum of PD1+PheoD1- as observed in PSII cores is virtually identical to that observed in the isolated D1D2-RC

  1. Study of Hydrothermal Mineralization in 2013 Drill Core from Hawaii Island

    NASA Astrophysics Data System (ADS)

    Lautze, N. C.; Calvin, W. M.; Moore, J.; Haskins, E.; Thomas, D. M.

    2014-12-01

    The Humu'ula Groundwater Research Project (HGRP) drilled a continuously-cored hole to nearly 2 km depth near the Saddle Road between Mauna Loa and Mauna Kea volcanoes on Hawaii Island in March of 2013. Temperatures at the bottom of the hole were unexpectedly high and reached over 100 C. A study is underway to characterize hydrothermal (secondary) mineralization in the core at depths below ~ 1 km. Secondary mineralization can indicate the presence, chemistry, and temperature of hydrothermal fluids, therein helping to characterize a present and/or past geothermal system. To date, the study is two pronged. In collaboration with University Nevada Reno (UNR) we used an Analytical Spectral Devices (ASD) FieldSpec instrument to obtain nearly 800 spectra from core depths spanning 3190 to 5785 feet. This device has a 2 cm contact probe that measures from 0.4 to 2.5 mm, and has been used successfully by UNR to identify depth-associated changes in alteration mineralogy and zoning in drill core from other pilot studies. The spectra indicate that rocks above a depth of ~1 km are only weakly altered. At greater depths to the base of the well, chlorite, possibly with some mica, and zeolites are common. The majority of zeolites are spectrally similar to each other at these wavelengths, however analcime and natrolite are uniquely identified in some sections. Epidote was not observed. The secondary mineral assemblages suggest that the alteration was produced by moderate temperature neutral pH fluids. Here, we used the spectral data as a survey tool to help identify and select over 20 sections of core for sampling and more detailed mineralogical analysis using traditional X-Ray Diffraction (XRD) and petrographic techniques, conducted in collaboration with University of Utah. This presentation will include mineral maps with depth and results of the petrographic analyses.

  2. Geochemical studies of backfill aggregates, lake sediment cores and the Hueco Bolson Aquifer

    NASA Astrophysics Data System (ADS)

    Thapalia, Anita

    This dissertation comprises of three different researches that focuses on the application of geochemistry from aggregates, lake sediment cores and Hueco Bolson Aquifer. Each study is independent and presented in the publication format. The first chapter is already published and the second chapter is in revision phase. Overall, three studies measure the large scale (field) as well as bench scale (lab) water-rock interactions influenced by the climatic and anthropogenic factors spans from the field of environmental geology to civil engineering. The first chapter of this dissertation addresses the chemical evaluation of coarse aggregates from six different quarries in Texas. The goal of this work is to find out the best geochemical methods for assessing the corrosion potential of coarse aggregates prior to their use in mechanically stabilized earth walls. Electrochemical parameters help to define the corrosion potential of aggregates following two different leaching protocols. Testing the coarse and fine aggregates demonstrate the chemical difference due to size-related kinetic leaching effects. Field fines also show different chemistry than the bulk rock indicating the weathering impact on carbonate rocks. The second chapter investigates zinc (Zn) isotopic signatures from eight lake sediment cores collected both from pristine lakes and those impacted by urban anthropogenic contamination. Zinc from the natural weathering of rocks and anthropogenic atmospheric pollutants are transported to these lakes and the signatures are recorded in the sediments. Isotopic analysis of core samples provides the signature of anthropogenic contamination sources. Dated sediment core and isotopic analysis can identify Zn inputs that are correlated to the landuse and population change of the watersheds. Comparison of isotopic data from both pristine and urban lake sediment core also serves as an analog in other lake sediment cores in the world. The third chapter studies on Hueco Bolson

  3. Image-guided Coring for Large-scale Studies in Molecular Pathology.

    PubMed

    Montaser-Kouhsari, Laleh; Knoblauch, Nicholas W; Oh, Eun-Yeong; Baker, Gabrielle; Christensen, Stephen; Hazra, Aditi; Tamimi, Rulla M; Beck, Andrew H

    2016-07-01

    Sampling of formalin-fixed paraffin-embedded (FFPE) tissue blocks is a critical initial step in molecular pathology. Image-guided coring (IGC) is a new method for using digital pathology images to guide tissue block coring for molecular analyses. The goal of our study is to evaluate the use of IGC for both tissue-based and nucleic acid-based projects in molecular pathology. First, we used IGC to construct a tissue microarray (TMA); second, we used IGC for FFPE block sampling followed by RNA extraction; and third, we assessed the correlation between nuclear counts quantitated from the IGC images and RNA yields. We used IGC to construct a TMA containing 198 normal and breast cancer cores. Histopathologic analysis showed high accuracy for obtaining tumor and normal breast tissue. Next, we used IGC to obtain normal and tumor breast samples before RNA extraction. We selected a random subset of tumor and normal samples to perform computational image analysis to quantify nuclear density, and we built regression models to estimate RNA yields from nuclear count, age of the block, and core diameter. Number of nuclei and core diameter were the strongest predictors of RNA yields in both normal and tumor tissue. IGC is an effective method for sampling FFPE tissue blocks for TMA construction and nucleic acid extraction. We identify significant associations between quantitative nuclear counts obtained from IGC images and RNA yields, suggesting that the integration of computational image analysis with IGC may be an effective approach for tumor sampling in large-scale molecular studies. PMID:26186251

  4. Image-guided Coring for Large-scale Studies in Molecular Pathology

    PubMed Central

    Montaser-Kouhsari, Laleh; Knoblauch, Nicholas W.; Oh, Eun-Yeong; Baker, Gabrielle; Christensen, Stephen; Hazra, Aditi; Tamimi, Rulla M.

    2016-01-01

    Sampling of formalin-fixed paraffin-embedded (FFPE) tissue blocks is a critical initial step in molecular pathology. Image-guided coring (IGC) is a new method for using digital pathology images to guide tissue block coring for molecular analyses. The goal of our study is to evaluate the use of IGC for both tissue-based and nucleic acid–based projects in molecular pathology. First, we used IGC to construct a tissue microarray (TMA); second, we used IGC for FFPE block sampling followed by RNA extraction; and third, we assessed the correlation between nuclear counts quantitated from the IGC images and RNA yields. We used IGC to construct a TMA containing 198 normal and breast cancer cores. Histopathologic analysis showed high accuracy for obtaining tumor and normal breast tissue. Next, we used IGC to obtain normal and tumor breast samples before RNA extraction. We selected a random subset of tumor and normal samples to perform computational image analysis to quantify nuclear density, and we built regression models to estimate RNA yields from nuclear count, age of the block, and core diameter. Number of nuclei and core diameter were the strongest predictors of RNA yields in both normal and tumor tissue. IGC is an effective method for sampling FFPE tissue blocks for TMA construction and nucleic acid extraction. We identify significant associations between quantitative nuclear counts obtained from IGC images and RNA yields, suggesting that the integration of computational image analysis with IGC may be an effective approach for tumor sampling in large-scale molecular studies. PMID:26186251

  5. Molecular dynamics study of crater formation by core-shell structured cluster impact

    NASA Astrophysics Data System (ADS)

    Aoki, Takaaki; Seki, Toshio; Matsuo, Jiro

    2012-07-01

    Crater formation processes by the impacts of large clusters with binary atomic species were studied using molecular dynamics (MD) simulations. Argon and xenon atoms are artificially organized in core-shell cluster structures with various component ratios and irradiated on a Si(1 0 0) target surface. When the cluster has Xe1000 core covered with 1000 Ar atoms, and impacts at a total of 20 keV, the core Xe cluster penetrates into the deep area, and a crater with a conical shape is left on the target. On the other hand, in the case of a cluster with the opposite structure, Ar1000 core covered with 1000 Xe atoms, the cluster stops at a shallow area of the target. The incident cluster atoms are mixed and tend to spread in a lateral direction, which results in a square shaped crater with a shallower hole and wider opening. The MD simulations suggest that large cluster impacts cause different irradiation effects by changing the structure, even if the component ratio is the same.

  6. Comparative structural and chemical studies of ferritin cores with gradual removal of their iron contents.

    PubMed

    Gálvez, Natividad; Fernández, Belén; Sánchez, Purificación; Cuesta, Rafael; Ceolín, Marcelo; Clemente-León, Miguel; Trasobares, Susana; López-Haro, Miguel; Calvino, Jose J; Stéphan, Odile; Domínguez-Vera, José M

    2008-06-25

    Transmission Electron Microscopy (TEM), X-ray Absorption Near Edge Spectroscopy (XANES), Electron Energy-Loss Spectroscopy (EELS), Small-Angle X-ray Scattering (SAXS), and SQUID magnetic studies were performed in a batch of horse spleen ferritins from which iron had been gradually removed, yielding samples containing 2200, 1200, 500, and 200 iron atoms. Taken together, findings obtained demonstrate that the ferritin iron core consists of a polyphasic structure (ferrihydrite, magnetite, hematite) and that the proportion of phases is modified by iron removal. Thus, the relative amount of magnetite in ferritin containing 2200 to 200 iron atoms rose steadily from approximately 20% to approximately 70% whereas the percentage of ferrihydrite fell from approximately 60% to approximately 20%. These results indicate a ferrihydrite-magnetite core-shell structure. It was also found that the magnetite in the ferritin iron core is not a source of free toxic ferrous iron, as previously believed. Therefore, the presence of magnetite in the ferritin cores of patients with Alzheimer's disease is not a cause of their increased brain iron(II) concentration. PMID:18507465

  7. Comparative study of mechanical properties of direct core build-up materials

    PubMed Central

    Kumar, Girish; Shivrayan, Amit

    2015-01-01

    Background and Objectives: The strength greatly influences the selection of core material because core must withstand forces due to mastication and para-function for many years. This study was conducted to evaluate certain mechanical properties of commonly used materials for direct core build-up, including visible light cured composite, polyacid modified composite, resin modified glass ionomer, high copper amalgam, and silver cermet cement. Materials and Methods: All the materials were manipulated according to the manufacturer's recommendations and standard test specimens were prepared. A universal testing machine at different cross-head speed was used to determine all the four mechanical properties. Mean compressive strength, diametral tensile strength, flexural strength, and elastic modulus with standard deviations were calculated. Multiple comparisons of the materials were also done. Results: Considerable differences in compressive strength, diametral tensile strength, and flexural strength were observed. Visible light cured composite showed relatively high compressive strength, diametral tensile strength, and flexural strength compared with the other tested materials. Amalgam showed the highest value for elastic modulus. Silver cermet showed less value for all the properties except for elastic modulus. Conclusions: Strength is one of the most important criteria for selection of a core material. Stronger materials better resist deformation and fracture provide more equitable stress distribution, greater stability, and greater probability of clinical success. PMID:25684905

  8. Climatic implications of background acidity and other chemistry derived from electrical studies of the Greenland Ice Core Project ice core

    NASA Astrophysics Data System (ADS)

    Wolff, Eric W.; Moore, John C.; Clausen, Henrik B.; Hammer, Claus U.

    1997-11-01

    High-resolution continuous profiles were obtained on the Greenland Ice Core Project (GRIP) ice core using two different electrical methods. After correction for temperature and density, the electrical conductivity method (ECM) technique responds only to acidity, while dielectric profiling (DEP) responds to acid, ammonium, and chloride. Detailed chemistry on a section of glacial-age ice allows us to confirm the calibration factor for chloride in DEP. Acidity dominates the DEP variability in the Holocene, Allerod/Bolling, and larger interstadials; ammonium dominates in the Younger Dry as, while chloride is the major contributor in cold periods including smaller interstadials. From the electrical signals plotted on a linear timescale we can deduce the background (nonvolcanic) acidity of the ice, varying from always acidic in the Holocene to always alkaline in the cold periods. In the interstadials, the ice is close to neutral, with most of it acidic in larger interstadials, most of it alkaline in smaller ones, and rapid alternations within interstadials. It is not clear whether neutralization of individual acidic particles occurred in the atmosphere or whether acid and alkaline particles coexisted until deposition in the snowpack. The changes in acidity observed at GRIP apply at least to all of Greenland and probably to much of North America. There would have been ecological effects and important changes in the uptake of some chemicals onto ice. If acidic sulfate particles were neutralized and removed from the atmosphere, which remains uncertain, then there are atmospheric chemistry and radiative effects that require further investigation.

  9. Regional climate signal modified by local factors - multi core study records (Lake Czechowskie region, N Poland)

    NASA Astrophysics Data System (ADS)

    Zawiska, Izabela; Rzodkiewicz, Monika; Noryśkiewicz, Agnieszka; Kramkowski, Mateusz; Obremska, Milena; Ott, Florian; Plessen, Birgit; Tjallingii, Rik; Słowiński, Michał; Błaszkiewicz, Mirosław; Brauer, Achim

    2016-04-01

    Lake sediments can be utilized as valuable paleoclimate and environmental archives as they contain information of past changes. Multi-proxy analyses of sedimentary compartments (e.g. pollen, diatoms, Cladocera) reveal those changes. However, to decipher the spatial variability of past climate changes and to define the proxies suited for local and regional scale reconstructions archive comparisons are needed. Here we present a detailed multi-proxy study from four different sediment cores covering the Younger Dryas cold period from the Lake Czechowskie region (N Poland). Three cores are located along a transect in the Lake Czechowskie basin from its deepest point towards a former lake bay close to today's shoreline. The fourth lacustrine sediment core was retrieved from the Trzechowskie paleolake, app. 1 km W from Lake Czechowskie. The dataset comprises information from pollen (AP, NAP, Juniperus, Betula-tree, Pinus silvestris), diatom (planktonic/benthic index, diatom valve concentration, dominant species), Cladocera (planktonic/benthic index, dominant species, number of Cladocera species, total sum of specimens) and geochemical (TOC and CaCO3 content, mineral matter, titanium) analyses. At the beginning of the Younger Dryas the AP pollen share decreased and NAP and Juniperus pollen increased in all studied locations. The mineral matter and titanium record showed higher values in two cores taken from the deepest parts of Lake Czechowskie and the core from Trzechowskie paleolake while in the core located at the marginal part of the lake it was already high in Allerød and it did not change much in Younger Dryas. The Cladocera based indexes: total sum of specimens and number of species decreased at the beginning of YD but on the contrary the Cladocera species composition changes were site-specific. The diatoms valve concentration index significantly lowered in core from the deep location while on the contrary increased in core from paleolake Trzechowskie. Our results

  10. Generic BWR-4 degraded core in-vessel study. Status report

    SciTech Connect

    Not Available

    1984-11-01

    Original intent of this project was to produce a phenomenological study of the in-vessel degradation which occurs during the TQUX and TQUV sequences for a generic BWR-4 from the initiation of the FSAR Chapter 15 operational transient through core debris bed formation to the failure of the primary pressure boundary. Bounding calculations were to be performed for the two high pressure and low pressure non-LOCA scenarios to assess the uncertainties in the current state of knowledge regarding the source terms for containment integrity studies. Source terms as such were defined in terms of hydrogen generation, unreacted metal, and coolant inventroy, and in terms of the form, sequencing and mode of dispersal through the primary vessel boundary. Fission product release was not to be considered as part of this study. Premature termination of the project, however, led to the dicontinuation of work on an as is basis. Work on the in-core phase from the point of scram to core debris bed formation was largely completed. A preliminary scoping calculation on the debris bed phase had been initiated. This report documents the status of the study at termination.

  11. Influence of Different Post-Core Systems on Impact Stress: a Pilot Study

    PubMed Central

    Kondoh, Yoshihiro; Takeda, Tomotaka; Ozawa, Takamitsu; Narimatsu, Keishiro; Konno, Michiyo; Fujii, Toshiki; Sekiguchi, Chieko; Nakajima, Kazunori; Ishigami, Keiichi; Shomura, Masahito

    2013-01-01

    This pilot study compared impact strain at the core and root surfaces between two different post-core systems. Materials and Methods: The form of a bovine mandibular front tooth was modified to resemble that of a human maxillary incisor as a test specimen. A cast post and core (Metal PC) and composite resin and glass fiber-reinforced epoxy resin post (Fiber-Resin PC) system were tested. Four gauges were affixed to the buccal and lingual surfaces of the core and root. The specimens were then embedded in a metal mold using dental stone. A pendulum-type device with a pyramid-shaped metal impact object with a titanium alloy head was used to provide 2 different shock forces. Maximum distortion was measured and analyzed. Results: Distortion at the core at each measurement point and total amount of distortion with Fiber-Resin PC was significantly greater (p<0.05) than that with Metal PC against both impact forces. On the other hand, distortion at the root at the buccal measurement point with Fiber-Resin PC was significantly less than that with Metal PC against both impact forces. Total distortion was significantly less with Fiber-Resin PC than that with Metal PC against the greater impact shock. Acceleration with Fiber-Resin PC was significantly less than that with Metal PC against both impact forces. Conclusion: Fiber-Resin PC has the potential to protect remaining root against traumatic force. This suggests that a Fiber-Resin PC is more suitable for non-vital teeth against not only occlusal but also traumatic impact force. PMID:24358064

  12. A study of the earth's free core nutation using international deployment of accelerometers gravity data

    NASA Technical Reports Server (NTRS)

    Cummins, Phil R.; Wahr, John M.

    1993-01-01

    In this study we consider the influence of the earth's free core nutation (FCN) on diurnal tidal admittance estimates for 11 stations of the globally distributed International Deployment of Accelerometers network. The FCN causes a resonant enhancement of the diurnal admittances which can be used to estimate some properties of the FCN. Estimations of the parameters describing the FCN (period, Q, and resonance strength) are made using data from individual stations and many stations simultaneously. These yield a result for the period of 423-452 sidereal days, which is shorter than theory predicts but is in agreement with many previous studies and suggests that the dynamical ellipticity of the core may be greater than its hydrostatic value.

  13. Paleomagnetic Study of Marine Sediment Core OR715-21 from Eastern Offshore of Taiwan

    NASA Astrophysics Data System (ADS)

    Lee, T.; Wei, K.; Huh, C.

    2009-12-01

    This study presents paleomagnetic secular variation results of a marine sediment core, named as OR715-21, taken from eastern offshore of Taiwan (121.5°E, 22.7°N, water depth 760 m). The total recovered length is 1.87 meters. Sediments in the core mainly consist of gray clay and silt. Planktonic foraminiferal shells (>250 μm, >6 mg, Globigerinoides spp. and Orbulina universa) were picked from six levels of the core and subjected to AMS 14C dating for constructing the age model. The results indicated that this core could support the information for the last 7000 years. The averaged sedimentation rate is estimated to be of about 26.5 cm/kyr. Psuedo-single domain (PSD) magnetite is identified as the most important magnetic carrier. Alternating field (AF) demagnetization was applied to treat the u-channel samples of the core. The median destructive field of the samples distributed between 15~25 mT. The characteristic remanent magnetization could be resolved after 20 mT cleaning. The paleo-declinations of the samples varied about ±200 around their mean and their paleo-inclinations varied between 300 and 500 . The variation pattern of the paleo-declination is somehow similar to the pattern compiled by Hyoto et al. (1993) based on the lake and marine sediment records from Japan except the varied amplitude is less between 4000 and 5000 yrB.P. Using NRM/ARM after 20 mT cleaning to simulate the paleo-intensity secular variation, our record shows that an increased trend began from 6500 yrB.P. to 3000 yrB.P., but decreased after. Magnetic proxies of this core indicate that 4 stages of environmental changes has happened in the area studied: (1) high magnetite abundance with relative low oxidized magnetic mineral contents occurred during ~6900 to 6200 yrB.P.; (2) a relative low abundance of magnetite with relative high oxidized magnetic minerals during ~6200 to ~5400 yrB.P.; (3) an abnormal low HIRM with relative higher ARM/SIRM could be found during the time period of ~5400

  14. Lack of Effect of Risperidone on Core Autistic Symptoms: Data from a Longitudinal Study

    PubMed Central

    Underwood-Riordan, Heather; Randall, Fellana; Zhang, Yi; Constantino, John N.

    2014-01-01

    Abstract Objective: The purpose of this study was to investigate the course of autistic symptoms, using a quantitative measure of core autistic traits, among risperidone-treated children who participated in a 10 year life course longitudinal study. Methods: Parents completed surveys of intervention history, as well as serial symptom severity measurements using the Social Responsiveness Scale (SRS), on their autism spectrum disorder (ASD)-affected children. Fifty participants (out of a total of 184 with full intervention histories) were reported to have been treated with risperidone during the course of the study. Serial SRS scores during risperidone treatment were available for a majority of children whose parents reported a positive effect from risperidone. Results: Two thirds of risperidone-treated children (n=33) were reported by parents to have improved by taking the medication, with the principal effects described being that children were calmer, better focused, and less aggressive. SRS scores of children reported to have responded positively to risperidone did not improve over time. Conclusions: Risperidone's beneficial effect on aggression and other elements of adaptive functioning were not necessarily accompanied by reduction in core ASD symptoms, as serially assessed by the same caregivers who reported improvement in their children. These results reflect the distinction between reduction in core symptom burden and improvement in adaptive functioning. Given the cumulative risks of atypical neuroleptics, the findings underscore the importance of periodic re-evaluation of medication benefit for children with ASD receiving neuroleptic treatment. PMID:25361070

  15. Comprehensive assessment of radiation dose estimates for the CORE320 study.

    PubMed

    Rybicki, Frank J; Mather, Richard T; Kumamaru, Kanako K; Brinker, Jeffrey; Chen, Marcus Y; Cox, Christopher; Matheson, Matthew B; Dewey, Marc; DiCarli, Marcelo F; Miller, Julie M; Geleijns, Jacob; George, Richard T; Paul, Narinder; Texter, John; Vavere, Andrea; Yaw, Tan Swee; Lima, Joao A C; Clouse, Melvin E

    2015-01-01

    OBJECTIVE. The purpose of this study was to comprehensively study estimated radiation doses for subjects included in the main analysis of the Combined Non-invasive Coronary Angiography and Myocardial Perfusion Imaging Using 320 Detector Computed Tomography (CORE320) study ( ClinicalTrials.gov identifier NCT00934037), a clinical trial comparing combined CT angiography (CTA) and perfusion CT with the reference standard catheter angiography plus myocardial perfusion SPECT. SUBJECTS AND METHODS. Prospectively acquired data on 381 CORE320 subjects were analyzed in four groups of testing related to radiation exposure. Radiation dose estimates were compared between modalities for combined CTA and perfusion CT with respect to covariates known to influence radiation exposure and for the main clinical outcomes defined by the trial. The final analysis assessed variations in radiation dose with respect to several factors inherent to the trial. RESULTS. The mean radiation dose estimate for the combined CTA and perfusion CT protocol (8.63 mSv) was significantly (p < 0.0001 for both) less than the average dose delivered from SPECT (10.48 mSv) and the average dose from diagnostic catheter angiography (11.63 mSv). There was no significant difference in estimated CTA-perfusion CT radiation dose for subjects who had false-positive or false-negative results in the CORE320 main analyses in a comparison with subjects for whom the CTA-perfusion CT findings were in accordance with the reference standard SPECT plus catheter angiographic findings. CONCLUSION. Radiation dose estimates from CORE320 support clinical implementation of a combined CT protocol for assessing coronary anatomy and myocardial perfusion. PMID:25539270

  16. Laboratory studies evaluating CO2 flood impact on the geomechanics of whole core samples

    SciTech Connect

    O'Connor, William K.

    2005-06-01

    Geological sequestration of CO2, whether by enhanced oil recovery (EOR), coal-bed methane (CBM) recovery, or saline aquifer injection is a promising near-term sequestration methodology. While tremendous experience exists for EOR, and CBM recovery has been demonstrated in existing fields, saline aquifer injection studies have only recently been initiated. Studies evaluating the availability of saline aquifers suitable for CO2 injection show great potential, however, the long-term fate of the injected CO2 in these ancient aqueous systems is still uncertain. Migration of the CO2 beyond the natural reservoir seals could become problematic, thus the identification of means to enhance the natural seals may help lead to the utilization of this sequestration methodology. Co-injection of a mineral reactant slurry, either with the CO2 or in separate, secondary injection wells, could provide a means to enhance the natural reservoir seals by providing the necessary cations for precipitation of mineral carbonates along the periphery of the injection plume. The subject study evaluates the merit of several mineral slurry co-injection strategies, by conduct of a series of laboratory-scale CO2 flood tests on whole core samples of the Mt. Simon sandstone from the Illinois Basin. By conducting these tests on whole core samples rather than crushed core, an evaluation of the impact of the CO2 flood on the rock mechanics properties as well as the geochemistry of the core and brine solution has been possible. This empirical data could provide a valuable resource for the validation of reservoir models under development for these engineered CO2 systems.

  17. N Reactor core heatup sensitivity study for the 32-inch unit cell model

    SciTech Connect

    Martin, F.; Zimmerman, B.; Heard, F.

    1988-02-01

    A number of N Reactor core heatup studies have been performed using the TRUMP-BD computer code. These studies were performed to address questions concerning the dependency of results on potential variations in the material properties and/or modeling assumptions. This report described and documents a series of 31 TRUMP-BD runs that were performed to determine the sensitivity of calculated inner-fuel temperatures to a variety of TRUMP input parameters and also to a change in the node density in a high-temperature-gradient region. The results of this study are based on the 32-in. model. 18 refs., 17 figs., 2 tab.

  18. A comparative study of dissociation of thymidine molecules following valence or core photoionization

    NASA Astrophysics Data System (ADS)

    Itälä, E.; Huels, M. A.; Rachlew, E.; Kooser, K.; Hägerth, T.; Kukk, E.

    2013-11-01

    We have studied the fragmentation of gas phase thymidine following valence and core ionization using synchrotron radiation, combined with electron energy and ion mass resolved detection in coincidence. To identify certain fragment masses 13C labelled thymidine was also used. We find that in large part, the photofragmentation of thymidine can be described as separated thymine and 2-deoxy-d-ribose cations. However, also the intact thymidine radical cation, formation of intact base and sugar cations from glycosidic bond cleavage and several new thymidine-specific fragments are observed after valence ionization. Conversely, at the photoionization of C 1s electrons neither parent thymidine cations nor any fragments above 55 amu were detected, and only ion pairs with small masses survive core ionization, Auger decay and the subsequent Coulomb separation of the DNA sub-unit. This demonstrates the genotoxic nature of soft x-rays which in cells induce complex clustered damage similar to those yielded by heavy particles.

  19. Study of thermal diffusivity of nanofluids with bimetallic nanoparticles with Au(core)/Ag(shell) structure

    NASA Astrophysics Data System (ADS)

    Gutierrez Fuentes, R.; Pescador Rojas, J. A.; Jiménez-Pérez, J. L.; Sanchez Ramirez, J. F.; Cruz-Orea, A.; Mendoza-Alvarez, J. G.

    2008-11-01

    The thermal diffusivity of Au/Ag nanoparticles with core/shell structure, at different compositions (Au/Ag = 3/1, 1/1, 1/3, 1/6), was measured by using the mismatched mode of the dual-beam thermal lens (TL) technique. This study determines the effect of the bimetallic composition on the thermal diffusivity of the nanofluids. In these results we find a lineal increment of the nanofluid it thermal diffusivity when the Ag shell thickness is increased. Our results show that the nanoparticle structure is an important parameter to improve the heat transport in composites and nanofluids. These results could have importance for applications in therapies and photothermal deliberation of drugs. Complementary measurements with UV-vis spectroscopy and TEM, were used to characterize the Au(core)/Ag(shell) nanoparticles.

  20. Core competencies for health professionals' training in pediatric behavioral sleep care: a Delphi study.

    PubMed

    Boerner, Katelynn E; Coulombe, J Aimée; Corkum, Penny

    2015-01-01

    The need to train non-sleep-specialist health professionals in evidence-based pediatric behavioral sleep care is well established. The objective of the present study was to develop a list of core competencies for training health professionals in assisting families of 1- to 10-year old children with behavioral insomnia of childhood. A modified Delphi methodology was employed, involving iterative rounds of surveys that were administered to 46 experts to obtain consensus on a core competency list. The final list captured areas relevant to the identification and treatment of pediatric behavioral sleep problems. This work has the potential to contribute to the development of training materials to prepare non-sleep-specialist health professionals to identify and treat pediatric behavioral sleep problems, ideally within stepped-care frameworks. PMID:24628091

  1. Developing a competence-based core curriculum in biomedical laboratory science: a Delphi study.

    PubMed

    Edgren, Gudrun

    2006-08-01

    In this study the Delphi technique has been used to develop a core curriculum for education of the biomedical scientist. The rapid development in biomedicine and the corresponding changes in methodology in biomedical laboratories demand careful planning of the education of biomedical scientists. The Delphi technique uses an anonymous panel of experts for suggestions and assessments aiming at consensus. Twenty-six experts from different kinds of hospital and university laboratories took part in the investigation. They suggested and assessed necessary competences for a recently graduated biomedical scientist, and if 75% or more of the participants agreed on a competence, it was included in the core curriculum. The final list consisted of 66 competences of varying depth, in three categories. This list contained several generic competences, concerning for example basic laboratory methods, handling of samples, dealing with apparatus and applying relevant rules and laws; basic knowledge in chemistry, preclinical medicine and laboratory methods; and finally attitudes that the panel expected in the recently graduated person. The core was sufficiently restricted to be used in a three-year programme and still leave space for about one year of electives/special study modules. It became rather traditional, e.g. it did not include competences that many recent reports consider important for the future professional. PMID:16973452

  2. FDTD study of the formation of optical vortices associated with core-shell nanoparticle cluster

    NASA Astrophysics Data System (ADS)

    Rahman, Md Mahfuzur; Lu, Jin You; Ni, George; Fang, Nicholas Xuanlai; Zhang, Tiejun; Ghaferi, Amal Al

    2015-03-01

    Light absorbing plasmonic metal-dielectric nanoparticles suspended in water, or nanofluids have recently been experimentally demonstrated to produce steam at high efficiencies upon solar illumination. This approach localizes high temperatures to the interior of the liquid through efficient trapping of incoming light via scattering and absorption mechanisms. In suspensions, nanoparticles may form clusters due to surface wetting properties, and little work has focused on understanding the optical properties of clusters. In this work, we use the FDTD method to accurately visualize the optical power flow through various plasmonic metal-silica core-shell nanoparticle pairs at different inter-particle separations (10-100 nm). At these separations phase singularities of the power flow can occur, such as vortices of light inside the dielectric core which can enhance the absorption cross-section of the cluster. We study the conditions required to form these vortices. We also consider titanium nitride as shell, other than the widely studied noble metals to visualize the extinction cross-section of a cluster which depends on the separation, and the permittivity of the dielectric core. The authors would like to acknowledge the valuable support from Masdar Institute and Massachusetts Institute of Technology for the soler thermal project grant.

  3. TEM Study of the Growth Mechanism, Phase Transformation, and Core/shell Structure of Semiconductor Nanowires

    NASA Astrophysics Data System (ADS)

    Wong, Tai Lun

    In this thesis, the fabrication and characterization of one-dimensional nanostructures have been studied systematically to understand the growth mechanism and structure transformation of one-dimensional nanostructures. The growth behavior of the ultrathin ZnSe nanowires with diameter less than 60 nm was found to be different from classical vapor-liquid-solid (VLS) process. The growth rate increases when the diameter of nanowires decreases, in contrast to the classical VLS process in which the growth rate increases with the diameter. The nucleation, initial growth, growth rates, defects, interface structures and growth direction of the nanowires were investigated by high resolution transmission electron microscopy (HRTEM). We found the structure and growth direction of ultra-thin nanowires are highly sensitive to growth temperatures and diameters of nanowires. At a low growth temperature (380°C), the growth direction for most nanowires is along <111>. Planar defects were found throughout the nanowires. At a high growth temperature (530°C), uniform nanowires with diameters around 10nm were grown along <110> and <112> directions, and the nanowires with diameters larger than 20nm were mainly grown along <111> direction. The possible growth mechanism of ultrathin nanowires was proposed by combining the solid catalytic growth with the interface diffusion theory, in order to explain how the growth temperature and the size of the catalysts influent the morphology, growth direction and growth rate of ultrathin nanowires. Structural and phase transformation of a nickel coated Si nanowire to NiSi2/SiC core-shell nanowire heterostructures has been investigated by the in-situ Transmission Electron Microscope (TEM). The phase transformation is a single-site nucleation process and therefore a single crystalline NiSi2 core resulted in the core-shell nanowire heterostructures. The transformation of the Si nanowire to NiSi2/SiC core-shell nanowire heterostructures was extremely

  4. New seismological attempts to study the top of the Earth's core

    NASA Astrophysics Data System (ADS)

    Tanaka, S.

    2007-12-01

    The seismological structure at the top of the Earth's core has been masked by the D", the base of the mantle, that is adjacent above the core. As increasing the high quality digital seismic data, the studies of the region have been revisited. First is the analysis of SmKS phases. Previously, the travel times of SKS, SKKS, and S3KS have been examined by using a regional array or an old global network of which distribution was sparse. Now I show that a new data set consisting of 1211 SmKS (m > 1) waveforms has been obtained from the recent permanent and temporary networks that exist between 1990 and 2003. The new data has been analyzed to investigate the radial seismic velocity structure around the core-mantle boundary (CMB). A stacked waveform at each distance bin coincides with reflectivity synthetic one for PREM very well, whereas those for other global models (iasp91, ak135, and SP6) yield disagreements. Furthermore, a waveform modeling for the D" structure results in a 30 km thick layer with a 10 percent S-wave velocity reduction at the mantle bottom as the best model while the SmKS modeling is insensitive to the lowermost mantle structures with thickness of several hundred kilometers. The possibility of a low P-wave velocity layer in the outermost core is remained because that the waveform fitness for the part of S4KS is improved by further introducing a 140 km thick layer with a 0.8 percent P-wave velocity reduction at the core top. However, a linear velocity gradient is assumed in the modeling of the outermost core. More complicated structure, such as the change of the velocity gradient, would be suffered from the trade-off between the velocity and the core radius. As discussed above, an independent approach is required to investigate to the core radius and topography of the CMB. Thus I have started another project. The combination of P4KP and PcP is suitable for canceling the hypocenter uncertainty and the regional variations in the mantle and the crust. To

  5. Optical properties of Au-core Pt-shell nanorods studied using FDTD simulations

    NASA Astrophysics Data System (ADS)

    Liu, Jian-Bo; Long, Lin; Zhang, Yu-Shi; Wang, Yue-Ping; Liu, Feng-Shou; Xu, Wei-Yao; Zong, Ming-Ji; Ma, Lei; Liu, Wen-Qi; Zhang, Hui; Yan, Jiao; Chen, Jia-Qi; Ji, Ying-Lu; Wu, Xiao-Chun

    2016-06-01

    Au-core/Pt-shell nanorods (Au@Pt NRs) have been prepared by a Au nanorod-mediated growth method, and they exhibit high electromagnetic field enhancements under coupling conditions. Boosted by a long-range effect of the high electromagnetic field generated by the Au core, the electromagnetic field enhancement can be controlled by changing the morphology of the nanostructures. In this study, we report the results on the simulations of the electromagnetic field enhancement using a finite difference time domain (FDTD) method, taking the real shapes of the Au@Pt NRs into account. Due to the "hot spot" effect, the electromagnetic field can be localized between the Pt nanodots. The electromagnetic field enhancement is found to be rather independent of the Pt content, whereas the local roughness and small sharp features might significantly modify the near-field. As the electromagnetic field enhancement can be tuned by the distribution of Pt nanodots over the Au-core, Au@Pt NRs can find potential applications in related areas.

  6. ACT-CCREC Core Research Program: Study Questions and Design. ACT Working Paper Series. WP-2015-01

    ERIC Educational Resources Information Center

    Cruce, Ty M.

    2015-01-01

    This report provides a non-technical overview of the guiding research questions and research design for the ACT-led core research program conducted on behalf of the GEAR UP College and Career Readiness Evaluation Consortium (CCREC). The core research program is a longitudinal study of the effectiveness of 14 GEAR UP state grants on the academic…

  7. A Study of a Failed Coronal Mass Ejection Core Associated with an Asymmetric Filament Eruption

    NASA Astrophysics Data System (ADS)

    Joshi, Navin Chandra; Srivastava, Abhishek K.; Filippov, Boris; Uddin, Wahab; Kayshap, Pradeep; Chandra, Ramesh

    2013-07-01

    We present multi-wavelength observations of an asymmetric filament eruption and associated coronal mass ejection (CME) and coronal downflows on 2012 June 17 and 18 from 20:00-05:00 UT. We use SDO/AIA and STEREO-B/SECCHI observations to understand the filament eruption scenario and its kinematics, while LASCO C2 observations are analyzed to study the kinematics of the CME and associated downflows. SDO/AIA limb observations show that the filament exhibits a whipping-like asymmetric eruption. STEREO/EUVI disk observations reveal a two-ribbon flare underneath the southeastern part of the filament that most probably occurred due to reconnection processes in the coronal magnetic field in the wake of the filament eruption. The whipping-like filament eruption later produces a slow CME in which the leading edge and the core propagate, with an average speed of ≈540 km s-1 and ≈126 km s-1, respectively, as observed by the LASCO C2 coronagraph. The CME core formed by the eruptive flux rope shows outer coronal downflows with an average speed of ≈56 km s-1 after reaching ≈4.33 R ⊙. Initially, the core decelerates at ≈48 m s-2. The plasma first decelerates gradually up to a height of ≈4.33 R ⊙ and then starts accelerating downward. We suggest a self-consistent model of a magnetic flux rope representing the magnetic structure of the CME core formed by an eruptive filament. This rope loses its previous stable equilibrium when it reaches a critical height. With some reasonable parameters, and inherent physical conditions, the model describes the non-radial ascending motion of the flux rope in the corona, its stopping at some height, and thereafter its downward motion. These results are in good agreement with observations.

  8. Bacterial study of Vostok drilling fluid: the tool to make ice core finding confident

    NASA Astrophysics Data System (ADS)

    Alekhina, I. A.; Petit, J. R.; Lukin, V. V.; Bulat, S. A.

    2003-04-01

    Decontamination of Vostok ice core is a critical issue in molecular biology studies. Core surface contains a film of hardly removable 'dirty' drilling fluid representing a mixture of polyhydrocarbons (PHC) including polyaromatic hydrocarbons (PAH) and freon. To make ice microbial finding more confident the original Vostok drilling fluid sampled from different depths (110m - 3600m) was analyzed for bacterial content by ribosomal DNA sequencing. Total, 33 clones of 16S ribosomal DNA were recovered from four samples of drilling fluid at 110, 2750, 3400, and 3600m leading to identification of 8 bacterial species. No overlapping was observed even for neighboring samples (3400m and 3600m). At present four major bacteria with the titer more than 103-104 cells per ml (as estimated from PCR results) are identified. Among them we found: unknown representative of Desulfobacteraceae which are able to oxidize sulphates and degrade benzenes (110m); PAH-degrading alpha-proteobacterium Sphingomonas natatoria (3400m); alpha-proteobacterium representing closely-related group of Sphingomonas sp. (e.g., S. aurantiaca) which are able to degrade PAH as well, and human pathogen closely related to Haloanella gallinarum of CFB group (3600m). Four additional species were revealed as single clones and showed relatedness to human pathogens and saprophytes as well as soil bacteria. These bacteria may represent drilling fluid contaminants introduced during its sampling or DNA extraction procedure. Of four major bacteria revealed, one species, Sphingomonas natatoria, has been met by us in the Vostok core from 3607 m depth (AF532054) whereas another Sphingomonas sp. which we refer to as S. aurantiaca was found in Antarctic microbial endolithic community (AF548567), hydrocarbon-containing soil near Scott Base in Antarctica (AF184221) and even isolated from 3593m Vostok accretion ice (AF324199) and Taylor Dome core (AF395031). The source for major human pathogen-related bacteria is rather uncertain

  9. The SNL100-02 blade : advanced core material design studies for the Sandia 100-meter blade.

    SciTech Connect

    Griffith, Daniel

    2013-11-01

    A series of design studies are performed to investigate the effects of advanced core materials and a new core material strategy on blade weight and performance for large blades using the Sandia 100-meter blade designs as a starting point. The initial core material design studies were based on the SNL100-01 100- meter carbon spar design. Advanced core material with improved performance to weight was investigated with the goal to reduce core material content in the design and reduce blade weight. A secondary element of the core study was to evaluate the suitability of core materials from natural, regrowable sources such as balsa and recyclable foam materials. The new core strategy for the SNL100-02 design resulted in a design mass of 59 tons, which is a 20% reduction from the most recent SNL100-01 carbon spar design and over 48% reduction from the initial SNL100-00 all-glass baseline blade. This document provides a description of the final SNL100-02 design, includes a description of the major design modifications, and summarizes the pertinent blade design information. This document is also intended to be a companion document to the distribution of the NuMAD blade model files for SNL100-02 that are made publicly available.

  10. A study of the compartmentalization of core-shell nanoparticles through fluorescence energy transfer of dopants.

    PubMed

    Chávez, Jorge L; Jiang, Hui; Duran, Randolph S

    2010-02-01

    Hybrid organic-inorganic templates and core-shell nanoparticles were used as models to study the communication between fluorescent probes placed inside nanoparticles. The hybrid templates were prepared on the basis of a mixed-surfactant system using octadecyltrimethoxysilane as a reactive amphiphile. The core-shell particles were obtained after coating of the templates with a siloxane shell, using the silanol groups on their surface. Atomic force microscopy imaging showed that the templates were made of a flexible material that flattened significantly after deposition on a substrate and evaporation of the solvent. Pyrene was sequestered by the templates in an aqueous suspension, which placed it in a nonpolar environment, as observed by its fluorescence response. Subsequently, double-doped templates were prepared by sequestering coumarin 153 (C153), with pyrene-doped hybrid templates. The communication between these probes was studied on the basis of their spectral properties, by means of fluorescence resonance energy transfer (FRET). Energy transfer between the dyes with efficiencies up to 55% was observed. Similarly, double-doped core-shell particles prepared on the basis of the hybrid templates were doped with this pair of dyes. Despite the presence of the shell, which was intended to increment the average separation between the probes, interaction of the dyes was observed, although with lower efficiencies. A similar study was performed with C153 and 4-(dicyanomethylene)-2-methyl-6-p-(dimethylamino)styryl-4H-pyran (DCM). FRET studies indicated that the probes were placed in proximity to each other. We confirmed these observations by means of fluorescence lifetime measurements, which showed a decrease in the lifetime of the donor upon addition of the acceptor. PMID:20023306

  11. Pathologic evaluation of a new endoscopic ultrasound needle designed to obtain core tissue samples: A pilot study

    PubMed Central

    Adler, Douglas G.; Witt, Benjamin; Chadwick, Barbara; Wells, Jason; Taylor, Linda Jo; Dimaio, Christopher; Schmidt, Robert

    2016-01-01

    Background and Objectives: Standard endoscopic ultrasound-fine-needle aspiration (EUS-FNA) needles are in widespread use. Meaningful differences between the available needles have been difficult to identify. Recently, a new EUS needle (Shark Core®, Covidien, Dublin, Leinster, Ireland), has been introduced in an attempt to improve diagnostic accuracy, tissue yield, and to potentially obtain a core tissue sample. We performed a pilot study prospectively to evaluate this new needle when compared to a standard EUS-FNA needle. Materials and Methods: Analysis of the first 15 patients undergoing EUS-FNA with the Shark Core needle was performed and it was compared to EUS-FNA in 15 patients who underwent EUS-FNA with a standard needle. Results: The Shark Core needle required fewer needle passes to obtain diagnostic adequacy than the standard needle [(χ2(1) = 11.3, P < 0.001]. The Shark Core needle required 1.5 passes to reach adequacy, whereas the standard needle required three passes. For cases with cell blocks, the Shark Core needle produced diagnostic material in 85% of cases [95% confidence interval (CI): 54–98], whereas the standard needle produced diagnostic material in 38% of the cases (95% CI: 9-76). The Shark Core needle produced actual tissue cores 82% of the time (95% CI: 48–98) and the standard needle produced no tissue cores (95% CI: 0-71) (P = 0.03). Conclusion: This pilot study found that the Shark Core needle had a high rate of producing adequate cytologic material for the diagnosis of pancreatic and peri-pancreatic lesions sampled by EUS with fewer passes required to obtain a definitive diagnosis and with a high rate of tissue cores being obtained when compared to a standard FNA needle.

  12. Nondestructive X-Ray Computed Tomography Analysis of Sediment Cores: A Case Study from the Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Oti, E.; Polyak, L. V.; Cook, A.; Dipre, G.

    2014-12-01

    Investigation of marine sediment records can help elucidate recent changes in the Arctic Ocean circulation and sea ice conditions. We examine sediment cores from the western Arctic Ocean, representing Late to Early Quaternary age (potentially up to 1 Ma). Previous studies of Arctic sediment cores indicate that interglacial/interstadial periods with relatively high sea levels and reduced ice cover are characterized by vigorous bioturbation, while glacial intervals have little to no bioturbation. Traditional methods for studying bioturbation require physical dissection of the cores, effectively destroying them. To treat this limitation, we evaluate archival sections of the cores using an X-ray Computed Tomography (XCT) scanner, which noninvasively images the sediment cores in three dimensions. The scanner produces density sensitive images suitable for quantitative analysis and for identification of bioturbation based on size, shape, and orientation. We use image processing software to isolate burrows from surrounding sediment, reconstruct them three-dimensionally, and then calculate their surface areas, volumes, and densities. Preliminary analysis of a core extending to the early Quaternary shows that bioturbation ranges from 0 to approximately 20% of the core's volume. In future research, we will quantitatively define the relationship between bioturbation activity and glacial regimes. XCT examination of bioturbation and other sedimentary features has the potential to shed light on paleoceanographic conditions such as sedimentation patterns and food flux. XCT is an alternative, underexplored investigation method that bears implications not only for illustrating paleoclimate variations but also for preserving cores for future, more advanced technologies.

  13. Influence of polar substituent on central bending unit of bent core mesogens: Synthesis, photophysical, mesomorphism and DFT studies

    NASA Astrophysics Data System (ADS)

    Paul, Manoj Kumar; Kalita, Gayatri; Bhattacharya, Barnali; Sarkar, Utpal

    2016-09-01

    New five ring bent core mesogens derived from substituted 1,3-phenylenediamine (4-nitro-1,3-phenylenediamine, 4-chloro-1,3-phenylenediamine) were synthesized. Their molecular structures, photophysical properties and mesogenic behaviors were investigated. The molecular structures and the purity of the bent core molecule have been characterized by spectroscopic studies and elemental analysis respectively. Photophysical properties of bent core compounds were investigated in chloroform by using UV-visible and fluorescence spectroscopic studies. The phase transition temperatures were detected by differential scanning calorimetry analysis and the phases are confirmed by polarizing optical microscopy. The polar substituents on bent core unit of bent shaped molecule influence the mesomorphic behaviors of the bent core mesogens. The polar nitro group at 4-position of the bent core unit displays tilted smectic C phase and unknown smectic X phase whereas chloro group at 4-position exhibits orthogonal smectic A phase. The bent core mesogens are fluorescent in nature. The density functional theory calculation was carried out to obtain the stable molecular conformation and chemical reactivity of the bent core molecules. Orbitals involved in the electronic transitions and their corresponding energies together with oscillator strengths have been reported.

  14. Core compressor exit stage study. Volume 4: Data and performance report for the best stage configuration

    NASA Technical Reports Server (NTRS)

    Wisler, D. C.

    1981-01-01

    The core compressor exit stage study program develops rear stage blading designs that have lower losses in their endwall boundary layer regions. The test data and performance results for the best stage configuration consisting of Rotor-B running with Stator-B are described. The technical approach in this efficiency improvement program utilizes a low speed research compressor. Tests were conducted in two ways: (1) to use four identical stages of blading to obtain test data in a true multistage environment and (2) to use a single stage of blading to compare with the multistage test results. The effects of increased rotor tip clearances and circumferential groove casing treatment are evaluated.

  15. First-Principles Study on β-SiC/BNNT Core/shell Nanocable

    NASA Astrophysics Data System (ADS)

    Zou, X. C.; Ouyang, J.; Wu, M. S.; Liu, G.; Lei, X. L.; Ouyang, C. Y.; Xu, B.

    2013-09-01

    In this paper, we studied the structural and electronic properties of core/shell nanocables composed of cubic silicon carbide nanowires (β-SiCNW) and boron nitride nanotubes (BNNT) using first-principles pseudopotential plane wave method within density functional theory. Our results show that the β-SiC/BNNT heterojunction structures are metallic, which primarily originates from the contributions of the BNNTs and the surfaces of SiCNWs. The BNNTs exhibit metallic characters after the SiC nanowires are inserted. The transition of the BNNTs is attributed to the charge transfer between BNNTs and SiCNWs.

  16. Core design studies for a 1000 MW{sub th} advanced burner reactor.

    SciTech Connect

    Kim, T. K.; Yang, W. S.; Grandy, C.; Hill, R.; Nuclear Engineering Division

    2009-04-01

    This paper describes the core design and performance characteristics of 1000 MW{sub th} Advanced Burner Reactor (ABR) core concepts with a wide range of TRU conversion ratio. Using ternary metal alloy and mixed oxide fuels, reference core designs of a medium TRU conversion ratio of {approx}0.7 were developed by trade-off between burnup reactivity loss and TRU conversion ratio. Based on these reference core concepts, TRU burner cores with low and high TRU conversion ratios were developed by changing the intra-assembly design parameters and core configurations. Reactor performance characteristics were evaluated in detail, including equilibrium cycle core performances, reactivity feedback coefficients, and shutdown margins. The results showed that by employing different assembly designs, a wide range of TRU conversion ratios from {approx}0.2 to break-even can be achieved within the same core without introducing significant performance and safety penalties.

  17. Influence of Full Veneer Restoration on Fracture Resistance of Three Different Core Materials: An Invitro Study

    PubMed Central

    Manoharan, P.S; Shekhawat, Kuldeep Singh; Deb, Saikat; Chidambaram, S.; Konchada, Jagadish; Venugopal, Nirupa; Vadivel, Harish

    2015-01-01

    Aims and Objectives One of the factor which affects the strength of the tooth restored with core material is the property of the material. In clinical situation all such restored teeth are protected by crowns. This study evaluated the strength of different core materials on a compromised tooth structure after restoration with a crown. Materials and Methods Seventy extracted intact human premolars were collected and mounted within a mould using auto-polymerizing resin. The teeth were divided in-to four groups - A, B, C and D. Each group contained 20 teeth except group A with 10 teeth. All the teeth were prepared for full veneer cast crown. Except for the teeth in group: A) extensive class-I cavities were prepared in the teeth of all the groups and restored with; B) composite resin, 3M EPSE Filtek P60; C) Silver reinforced glass ionomer, SHOFU Hi Dense XP and; (D) Resin reinforced glass ionomer, GC Gold Label light cure GIC. All the teeth were restored with cast-metal alloy and exposed to 1.2 million cycles of cyclic loading in a chewing simulator. Subsequently, the teeth that survived were loaded till fracture in the universal testing machine. Fracture loads and type of fractures were recorded. Results All the specimens survived cyclic loading. The mean fracture strength of the silver reinforced glass ionomer was greater with and without crown (p<0.001). Statistical analysis for the mean fracture load of each specimen showed significant difference between the groups. Conclusion Under the condition of this study, core materials when restored with artificial crown had a significant increase in fracture resistance. PMID:26501004

  18. FNAC Versus Core Needle Biopsy: A Comparative Study in Evaluation of Palpable Breast Lump

    PubMed Central

    Saha, Abhijit; Mukhopadhyay, Madhumita; Sarkar, Koushik; Saha, Ashis Kumar; Sarkar, Diptendra KR

    2016-01-01

    Introduction Breast carcinoma is the most common malignant tumour and the leading cause of carcinoma death in women in world. The main purpose of FNAC or CNB of breast lumps is to confirm cancer preoperatively and to avoid unnecessary surgery in specific benign conditions. Aims and Objective The objective of the study was to compare between Fine Needle Aspiration Cytology (FNAC) and Core Needle Biopsy (CNB) in the diagnosis of breast carcinoma with final histological diagnosis from excision specimen as it is gold standard. Materials and Methods A prospective study was done on 50 cases. Patients undergoing all three procedures (Fine Needle Aspiration Cytology and Core Needle Biopsy done at Department of Pathology; subsequent excision surgeries done at Department of General Surgery) were selected. May Grunwald Giemsa (MGG) and Papaniculou (PAP) staining were performed on cytology smears. Haematoxylin and Eosin (H&E) staining was done on both the CNB and tissue specimens obtained from subsequent excision surgeries to see the histological features. Results FNAC showed sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 69%, 100%, 100%, 38.1%, and 74% respectively in diagnosing carcinoma. CNB had sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of 88.3%, 100%, 100%, 53.3% and 86%. Both FNAC and CNB showed statistically significant correlation with confirmatory HPE of excision specimen (p-value <0.05) in the diagnosis of breast carcinoma. Conclusion Fine needle aspiration cytology (FNAC) is a rapid, less complicated, economical, reliable and relevant method for the preoperative pathological diagnosis of breast carcinoma in a developing nation like ours. If the initial FNAC is inadequate, core needle biopsy (CNB) can be a useful second line method of pathological diagnosis in order to minimize the chance of missed diagnosis of breast cancer. PMID:27042469

  19. A theoretical study on the advantage of core-shell particles with radially-oriented mesopores.

    PubMed

    Deridder, Sander; Catani, Martina; Cavazzini, Alberto; Desmet, Gert

    2016-07-22

    We report on a first-principles numerical study explaining the potential advantage of core-shell particles with strictly radially-oriented mesopores. Comparing the efficiency of these particles with fully porous and core-shell particles with a conventional (i.e., randomly oriented) mesopore network, the present numerical study shows a similar strong reduction in minimal reduced plate height (hmin) as was very recently observed in an experimental study by Wei et al. (respectively a hmin-reduction on the order of about 1 and 0.5 reduced plate height-units). As such, the present work provides a theoretical basis to understand and confirm their experimental findings and quantifies the general advantage of "radial-diffusion-only" particles. Determining the effective longitudinal diffusion (B-term contribution) in a series of dedicated, independent simulations, it was found that this contribution can be described by a very simple, yet fully exact mathematical expression for the case of "radial- diffusion-only" particles. Using this expression, the significant increase in efficiency of these particles can be fully attributed to their much smaller B-term band broadening, while their C-term band broadening (representing the mass transfer resistance) remains unaffected. PMID:27317003

  20. Core Competencies: The Challenge For Graduate Peace and Conflict Studies Education

    NASA Astrophysics Data System (ADS)

    Windmueller, John; Wayne, Ellen Kabcenell; Botes, Johannes (Jannie)

    2009-05-01

    This article uses a case study of the assessment of a graduate program in negotiations and conflict management as a springboard for discussing several critical, but unanswered questions in our field. It raises questions regarding the lack of clear core competencies and expectations regarding curricula at the graduate-level of peace and conflict studies programs, as well as concerns over how educators in this field can or should assess their own work and train students for practice. It also addresses, via a comparative case analysis in Tajikistan, the degree to which the competencies and pedagogical approaches in this field are culturally bound. The picture that emerges from these case studies suggests that there have been important omissions in the way that the varied educational programs and the larger peace and conflict studies field itself have developed thus far.

  1. Petrologic studies of drill cores USW-G2 and UE25b-1H, Yucca Mountain, Nevada

    SciTech Connect

    Caporuscio, F.; Vaniman, D.; Bish, D.; Broxton, D.; Arney, B.; Heiken, G.; Byers, F.; Gooley, R.; Semarge, E.

    1982-07-01

    The tuffs of the Nevada Test Site are currently under investigation as a possible deep geologic site for high-level radioactive waste disposal. This report characterizes tuff retrieved in core from two drill holes, USW-G2 and UE25b-1H, at the Yucca Mountain block. The USW-G2 drill core is from the northernmost extent of the block, whereas UE25b-1H is adjacent to an earlier drill hole, UE25a-1. The drill cores USW-G2 and UE25b-1H bottomed at 6000 and 4200 ft, respectively. Petrographic and x-ray diffraction studies of the two drill cores are presented in this report and indicate that tuffs (composed primarily of variably welded ash flows) are partially recrystallized to secondary minerals. Correlations of stratigraphy are also made with previous drill cores from Yucca Mountain.

  2. [Study on trace elements of lake sediments by ICP-AES and XRF core scanning].

    PubMed

    Cheng, Ai-Ying; Yu, Jun-Qing; Gao, Chun-Liang; Zhang, Li-Sha; He, Xian-Hu

    2013-07-01

    It is the first time to study sediment of Toson lake in Qaidam Basin. Trace elements including Cd, Cr, Cu, Zn and Pb in lake sediment were measured by ICP-AES method, studied and optimized from different resolution methods respectively, and finally determined a optimum pretreatment system for sediment of Toson lake, namely, HCl-HNO3-HF-HClO4-H2O2 system in the proportions of 5 : 5 : 5 : 1 : 1 was determined. At the same time, the data measured by XRF core scanning were compared, the use of moisture content correction method was analyzed, and the influence of the moisture content on the scanning method was discussed. The results showed that, compared to the background value, the contents of Cd and Zn were a little higher, the content of Cr, Cu and Pb was within the background value limits. XRF core scanning was controlled by sediment elements as well as water content in sediment to some extent. The results by the two methods showed a significant positive correlation, with the correlation coefficient up to 0.673-0.925, and they have a great comparability. PMID:24059207

  3. Developing a common bean core collection suitable for association mapping studies

    PubMed Central

    Perseguini, Juliana Morini Küpper Cardoso; Silva, Gliciane Micaele Borges; Rosa, João Ricardo Bachega Feijó; Gazaffi, Rodrigo; Marçal, Jéssica Fernanda; Carbonell, Sérgio Augusto Morais; Chiorato, Alisson Fernando; Zucchi, Maria Imaculada; Garcia, Antonio Augusto Franco; Benchimol-Reis, Luciana Lasry

    2015-01-01

    Because of the continuous introduction of germplasm from abroad, some collections have a high number of accessions, making it difficult to explore the genetic variability present in a germplasm bank for conservation and breeding purposes. Therefore, the aim of this study was to quantify and analyze the structure of genetic variability among 500 common bean accessions to construct a core collection. A total of 58 SSRs were used for this purpose. The polymorphism information content (PIC) in the 180 common bean accessions selected to compose the core collection ranged from 0.17 to 0.86, and the discriminatory power (DP) ranged from 0.21 to 0.90. The 500 accessions were clustered into 15 distinct groups and the 180 accessions into four distinct groups in the Structure analysis. According to analysis of molecular variance, the most divergent accessions comprised 97.2% of the observed genetic variability present within the base collection, confirming the efficiency of the selection criterion. The 180 selected accessions will be used for association mapping in future studies and could be potentially used by breeders to direct new crosses and generate elite cultivars that meet current and future global market needs. PMID:25983627

  4. Perforation of aluminium foam core sandwich panels under impact loading: A numerical and analytical study

    NASA Astrophysics Data System (ADS)

    Elnasri, Ibrahim; Zhao, Han

    2015-09-01

    This paper reports the numerical results of the inversed perforation test instrumented with Split Hopkinson Pressure Bar SHPB with an instrumented pressure bar on the AlSi7Mg0.5 aluminium foam core sandwich panels with 0.8 mm thick 2024 T3 aluminium top and bottom skin. The numerical models are developed in order to understand the origin of the enhancement of the top skin loads found under impact loading (paper published by [1]). Numerical predicted piercing force vs displacement curves are compared with experimental measurements (tests at impact velocities at 27 and 44 m/s). The simulation catches all process of the perforation of the sandwich panels (top skin, foam core, and bottom skin). Within experimental scatter, there is a good agreement between numerical predictions and experimental measurements. Virtual tests with different impact velocities up 200 m/s are presented and showed a significant enhancement of the piercing force under impact loading (top skin peak and foam core plateau loads). In order to understand the origin of these force enhancements, any difference of detailed local information between static and dynamic loading is studied and showed that a shock front effect is responsible for the enhancement piercing force. An analytical model using an improved RPPL shock model based a power law densification assumption is proposed to calculate the top skin piercing force. The improved RPPL shock model agrees with the FE results for small velocities and gives better prediction of the piercing force than the RPPL shock model for large velocities (>100 m/s).

  5. A STUDY OF A FAILED CORONAL MASS EJECTION CORE ASSOCIATED WITH AN ASYMMETRIC FILAMENT ERUPTION

    SciTech Connect

    Joshi, Navin Chandra; Srivastava, Abhishek K.; Uddin, Wahab; Kayshap, Pradeep; Filippov, Boris; Chandra, Ramesh E-mail: njoshi98@gmail.com

    2013-07-01

    We present multi-wavelength observations of an asymmetric filament eruption and associated coronal mass ejection (CME) and coronal downflows on 2012 June 17 and 18 from 20:00-05:00 UT. We use SDO/AIA and STEREO-B/SECCHI observations to understand the filament eruption scenario and its kinematics, while LASCO C2 observations are analyzed to study the kinematics of the CME and associated downflows. SDO/AIA limb observations show that the filament exhibits a whipping-like asymmetric eruption. STEREO/EUVI disk observations reveal a two-ribbon flare underneath the southeastern part of the filament that most probably occurred due to reconnection processes in the coronal magnetic field in the wake of the filament eruption. The whipping-like filament eruption later produces a slow CME in which the leading edge and the core propagate, with an average speed of Almost-Equal-To 540 km s{sup -1} and Almost-Equal-To 126 km s{sup -1}, respectively, as observed by the LASCO C2 coronagraph. The CME core formed by the eruptive flux rope shows outer coronal downflows with an average speed of Almost-Equal-To 56 km s{sup -1} after reaching Almost-Equal-To 4.33 R{sub Sun }. Initially, the core decelerates at Almost-Equal-To 48 m s{sup -2}. The plasma first decelerates gradually up to a height of Almost-Equal-To 4.33 R{sub Sun} and then starts accelerating downward. We suggest a self-consistent model of a magnetic flux rope representing the magnetic structure of the CME core formed by an eruptive filament. This rope loses its previous stable equilibrium when it reaches a critical height. With some reasonable parameters, and inherent physical conditions, the model describes the non-radial ascending motion of the flux rope in the corona, its stopping at some height, and thereafter its downward motion. These results are in good agreement with observations.

  6. Core strengthening.

    PubMed

    Arendt, Elizabeth A

    2007-01-01

    Several recent studies have evaluated interventional techniques designed to reduce the risk of serious knee injuries, particularly noncontact anterior cruciate ligament injuries in female athletes. Maintenance of rotational control of the limb underneath the pelvis, especially in response to cutting and jumping activities, is a common goal in many training programs. Rotational control of the limb underneath the pelvis is mediated by a complex set of factors including the strength of the trunk muscles and the relationship between the core muscles. It is important to examine the interrelationship between lower extremity function and core stability. PMID:17472321

  7. A Combined He and Os Isotopic Study of the HSDP-2 Core from Mauna Kea, Hawaii

    NASA Astrophysics Data System (ADS)

    Ireland, T. J.; Walker, R. J.; Depaolo, D. J.; Kurz, M. D.

    2004-12-01

    Combined osmium and helium isotope systematics of hotspot lavas have the potential to reveal information about the deep Earth. A high 3He/4He ratio may represent an undegassed reservoir, generally associated with the lower mantle. There are two Os isotopes that can be studied to help to further elucidate the problem. The decay of 187Re to 187Os is the more frequently cited system; however, in terms of lower mantle processes, the decay of 190Pt to 186Os may be extremely useful. Both of these Os isotopes are enriched in the core relative to chondritic values. In a previous study, Brandon et al. (1999) examined several Hawaiian volcanoes for both He and Os isotopes. A correlation was noted between the 3He/4He, 187Os/188Os and 186Os/188Os ratios. In terms of 3He/4He and 187Os/188Os space, the three commonly cited Hawaiian end-members (Kea, Koolau and Loihi members) were clearly defined. A strong positive correlation was also observed for 186Os/188Os versus 3He/4He. These correlations were interpreted as a possible signature of core-mantle interaction. There were some limitations to previous studies. Only 2-3 samples from each volcano were studied, with these samples generally being subaerially erupted. The He data utilized were often not for the same samples for which the Os data were collected (volcano averages for He were used on some samples). With the introduction of data from the Hawaiian Scientific Drilling Project (HSDP-2), which drilled 2.84 km into the Mauna Kea volcanics (DePaolo et al., 2000), an extensive history of a single volcano can be observed (from the early submarine stages to the later subaerial rocks). In the current study a detailed Os isotopic analysis of several samples that span a large depth range of the HSDP-2 core, in conjunction with previously collected He isotopic data (Kurz et al., 2004), was conducted. The samples define a relatively narrow range of slightly suprachondritic 187Os/188Os ratios (0.12865-0.13056), despite having a large

  8. Energy transfer and trapping in the photosystem I core antenna. A temperature study.

    PubMed Central

    Werst, M; Jia, Y; Mets, L; Fleming, G R

    1992-01-01

    The fluorescence decay kinetics of the photosystem I-only mutant strain of Chlamydomonas reinhardtii, A4d, are used to study energy transfer and structural organization in photosystem I (PSI). Time-resolved measurements over a wide temperature range (36-295 K) have been made both on cells containing approximately 65 core chl a/P700 and an additional 60-70 chl a + b from LHC proteins and on PSI particles containing 40-50 chl a/P700. In each case, the fluorescence decay kinetics is dominated by a short component, tau 1 which is largely attributed to the lifetime of the excitations in the core complex. The results are discussed in terms of simulations of the temperature dependence of tau 1 in model systems. Spectral inhomogeneity and the temperature dependence of the spectral lineshapes are included explicitly in the simulations. Various kinds of antenna arrangements are modeled with and without the inclusion of pigments with lower absorption energies than the trap (red pigments). We conclude that funnel arrangements are not consistent with our measurements. A random model that includes one or two red pigments placed close to the trap shows temperature and wavelength dependence similar to that observed experimentally. A comparison of the temperature dependence of tau 1 for cells and PSI particles is included. PMID:1581501

  9. Tokamak Fusion Core Experiment: design studies based on superconducting and hybrid toroidal field coils. Design overview

    SciTech Connect

    Flanagan, C.A.

    1984-10-01

    This document is a design overview that describes the scoping studies and preconceptual design effort performed in FY 1983 on the Tokamak Fusion Core Experiment (TFCX) class of device. These studies focussed on devices with all-superconducting toroidal field (TF) coils and on devices with superconducting TF coils supplemented with copper TF coil inserts located in the bore of the TF coils in the shield region. Each class of device is designed to satisfy the mission of ignition and long pulse equilibrium burn. Typical design parameters are: major radius = 3.75 m, minor radius = 1.0 m, field on axis = 4.5 T, plasma current = 7.0 MA. These designs relay on lower hybrid (LHRH) current rampup and heating to ignition using ion cyclotron range of frequency (ICRF). A pumped limiter has been assumed for impurity control. The present document is a design overview; a more detailed design description is contained in a companion document.

  10. A mapping study of massive cores with 13CO J = 1 0 line

    NASA Astrophysics Data System (ADS)

    Esimbek, Jarken; Wu, Yuefang; Wang, Yang

    2008-04-01

    Using 13.7 m telescope of Qinghai station of Purple Mountain Observatory (PMO) at Delingha, 27 sources were observed with 12CO J = 1-0 and mapped with 13CO J = 1-0 lines. Midcourse Space Experiment (MSX) images and IRAS point source catalogue (PSC) were used to identify stellar objects embedded in the detected cores. Forty-one 13CO cores were obtained. The sizes of these cores is from 0.4 pc to 7 pc. Their average excitation temperatures and masses are 23.4 K and 3.1 × 10 4M⊙, which shows that these cores are massive and relatively cold. The line widths are much wider than those of low-mass cores. The correlation between line widths and core sizes is weak. According to the radio, IRAS and MSX data, there are three kinds of cores in the entire sample: group A has 21 cores whose Tex and Δ V are 15.5 K and 3.2 km/s on the average. The cores in group A are not associated with infrared sources. Group B contains 17 cores, of which five are associated with IRAS sources, the remaining 12 are associated with MSX sources. All the 17 cores are not associated with UC HII regions. Group C contains three cores which are associated with UC HII regions. All these physical parameters indicate that there could be an evolutionary development from group A to group C. The bolometric luminosities of groups B and C are also investigated. The reason for the displacement of the cores and the infrared sources in group A was discussed.

  11. International perspective on common core competencies for occupational physicians: a modified Delphi study

    PubMed Central

    Lalloo, Drushca; Demou, Evangelia; Kiran, Sibel; Cloeren, Marianne; Mendes, René; Macdonald, Ewan B

    2016-01-01

    Objectives The competencies required of occupational physicians (OPs) have been the subject of peer-reviewed research in Europe and individual countries around the world. In the European Union (EU), there has been development of guidance on training and common competencies, but little research has extended beyond this. The aim of this study was to obtain consensus on and identify the common core competencies required of OPs around the world. Methods A modified Delphi study was carried out among representative organisations and networks of OPs in a range of countries around the world. It was conducted in 2 rounds using a questionnaire based on the specialist training syllabus of a number of countries, expert panel reviews and conference discussions. Results Responses were received from 51 countries around the world, with the majority from Europe (60%; 59%) and North and South America (24%; 32%) in rounds 1 and 2, respectively. General principles of assessment and management of occupational hazards to health and good clinical care were jointly considered most important in ranking when compared with the other topic areas. Assessment of disability and fitness for work, communication skills and legal and ethical issues completed the top five. In both rounds, research methods and teaching and educational supervision were considered least important. Conclusions This study has established the current priorities among OPs across 51 countries of the common competencies required for occupational health (OH) practice. These findings can serve as a platform for the development of common core competencies/qualifications within specific geographical regions or internationally. This is particularly pertinent with globalisation of commerce and free movement within the EU. PMID:27076063

  12. A comparative study on liquid core formulation on the diameter on the alginate capsules

    NASA Astrophysics Data System (ADS)

    Ong, Hui-Yen; Lee, Boon-Beng; Radzi, AkmalHadi Ma'; Zakaria, Zarina; Chan, Eng-Seng

    2015-08-01

    Liquid core capsule has vast application in biotechnology related industries such as pharmaceutical, medical, agriculture and food. Formulation of different types of capsule was important to determine the performance of the capsule. Generally, the liquid core capsule with different formulations generated different size of capsule.Therefore, the aim of this project is to investigate the effect of different liquid core solution formulations on the diameter of capsule. The capsule produced by extruding liquid core solutions into sodium alginate solution. Three types of liquid core solutions (chitosan, xanthan gum, polyethylene glycol (PEG)) were investigated. The results showed that there is significant change in capsule diameter despite in different types of liquid core solution were used and a series of capsule range in diameter of 3.1 mm to 4.5 mm were produced. Alginate capsule with chitosan formulation appeared to be the largest capsule among all.

  13. Synthesis and cytotoxicity study of magnesium ferrite-gold core-shell nanoparticles.

    PubMed

    Nonkumwong, Jeeranan; Pakawanit, Phakkhananan; Wipatanawin, Angkana; Jantaratana, Pongsakorn; Ananta, Supon; Srisombat, Laongnuan

    2016-04-01

    In this work, the core-magnesium ferrite (MgFe2O4) nanoparticles were prepared by hydrothermal technique. Completed gold (Au) shell coating on the surfaces of MgFe2O4 nanoparticles was obtained by varying core/shell ratios via a reduction method. Phase identification, morphological evolution, optical properties, magnetic properties and cytotoxicity to mammalian cells of these MgFe2O4 core coated with Au nanoparticles were examined by using a combination of X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy, UV-visible spectroscopy (UV-vis), vibrating sample magnetometry and resazurin microplate assay techniques. In general, TEM images revealed different sizes of the core-shell nanoparticles generated from various core/shell ratios and confirmed the completed Au shell coating on MgFe2O4 core nanoparticles via suitable core/shell ratio with particle size less than 100nm. The core-shell nanoparticle size and the quality of coating influence the optical properties of the products. The UV-vis spectra of complete coated MgFe2O4-Au core-shell nanoparticles exhibit the absorption bands in the near-Infrared (NIR) region indicating high potential for therapeutic applications. Based on the magnetic property measurement, it was found that the obtained MgFe2O4-Au core-shell nanoparticles still exhibit superparamagnetism with lower saturation magnetization value, compared with MgFe2O4 core. Both of MgFe2O4 and MgFe2O4-Au core-shell also showed in vitro non-cytotoxicity to mouse areola fibroblast (L-929) cell line. PMID:26838832

  14. Synthetic Studies on Et-743. Assembly of the Pentacyclic Core and a Formal Total Synthesis

    PubMed Central

    Fishlock, Dan; Williams, Robert M.

    2009-01-01

    A formal total synthesis of the potent anticancer agent Et-743 is described. The tetrahydroisoquinoline core is stereoselectively constructed using a novel radical cyclization of a glyoxalimine. Further elaboration of this core rapidly accessed the pentacyclic core of Et-743, but a mixture of regiosisomers was obtained in the key Pictet-Spengler ring closure. A known advanced intermediate in the synthesis of Et-743 was intercepted, constituting a formal synthesis of the molecule. PMID:18687003

  15. Six weeks of core stability training improves landing kinetics among female capoeira athletes: a pilot study.

    PubMed

    Araujo, Simone; Cohen, Daniel; Hayes, Lawrence

    2015-03-29

    Core stability training (CST) has increased in popularity among athletes and the general fitness population despite limited evidence CST programmes alone lead to improved athletic performance. In female athletes, neuromuscular training combining balance training and trunk and hip/pelvis dominant CST is suggested to reduce injury risk, and specifically peak vertical ground reaction forces (vGRF) in a drop jump landing task. However, the isolated effect of trunk dominant core stability training on vGRF during landing in female athletes had not been evaluated. Therefore, the objective of this study was to evaluate landing kinetics during a drop jump test following a CST intervention in female capoeira athletes. After giving their informed written consent, sixteen female capoeira athletes (mean ± SD age, stature, and body mass of 27.3 ± 3.7 years, 165.0 ± 4.0 cm, and 59.7 ± 6.3 kg, respectively) volunteered to participate in the training program which consisted of static and dynamic CST sessions, three times per week for six weeks. The repeated measures T-test revealed participants significantly reduced relative vGRF from pre- to post-intervention for the first (3.40 ± 0.78 vs. 2.85 ± 0.52 N·NBW-1, respectively [p<0.05, effect size = 0.60]), and second landing phase (5.09 ± 1.17 vs. 3.02 ± 0.41 N·NBW-1, respectively [p<0.001, effect size = 0.87]). The average loading rate was reduced from pre- to post-intervention during the second landing phase (30.96 ± 18.84 vs. 12.06 ± 9.83 N·NBW·s-1, respectively [p<0.01, effect size = 0.68]). The peak loading rate was reduced from pre- to post-intervention during the first (220.26 ± 111.51 vs. 120.27 ± 64.57 N·NBW·s-1 respectively [p<0.01, effect size = 0.64]), and second (99.52 ± 54.98 vs. 44.71 ± 30.34 N·NBW·s-1 respectively [p<0.01, effect size = 0.70]) landing phase. Body weight, average loading rate during the first landing phase, and jump height were not significantly different between week 0 and week 6

  16. Six Weeks of Core Stability Training Improves Landing Kinetics Among Female Capoeira Athletes: A Pilot Study

    PubMed Central

    Araujo, Simone; Cohen, Daniel; Hayes, Lawrence

    2015-01-01

    Core stability training (CST) has increased in popularity among athletes and the general fitness population despite limited evidence CST programmes alone lead to improved athletic performance. In female athletes, neuromuscular training combining balance training and trunk and hip/pelvis dominant CST is suggested to reduce injury risk, and specifically peak vertical ground reaction forces (vGRF) in a drop jump landing task. However, the isolated effect of trunk dominant core stability training on vGRF during landing in female athletes had not been evaluated. Therefore, the objective of this study was to evaluate landing kinetics during a drop jump test following a CST intervention in female capoeira athletes. After giving their informed written consent, sixteen female capoeira athletes (mean ± SD age, stature, and body mass of 27.3 ± 3.7 years, 165.0 ± 4.0 cm, and 59.7 ± 6.3 kg, respectively) volunteered to participate in the training program which consisted of static and dynamic CST sessions, three times per week for six weeks. The repeated measures T-test revealed participants significantly reduced relative vGRF from pre- to post-intervention for the first (3.40 ± 0.78 vs. 2.85 ± 0.52 N·NBW-1, respectively [p<0.05, effect size = 0.60]), and second landing phase (5.09 ± 1.17 vs. 3.02 ± 0.41 N·NBW-1, respectively [p<0.001, effect size = 0.87]). The average loading rate was reduced from pre- to post-intervention during the second landing phase (30.96 ± 18.84 vs. 12.06 ± 9.83 N·NBW·s-1, respectively [p<0.01, effect size = 0.68]). The peak loading rate was reduced from pre- to post-intervention during the first (220.26 ± 111.51 vs. 120.27 ± 64.57 N·NBW·s-1 respectively [p<0.01, effect size = 0.64]), and second (99.52 ± 54.98 vs. 44.71 ± 30.34 N·NBW·s-1 respectively [p<0.01, effect size = 0.70]) landing phase. Body weight, average loading rate during the first landing phase, and jump height were not significantly different between week 0 and week 6

  17. Nanofilms on Hollow Core Fiber-Based Structures: An Optical Study

    NASA Astrophysics Data System (ADS)

    Bravo, Javier; Matías, Ignacio R.; Del Villar, Ignacio; Corres, Jesús M.; Arregui, Francisco J.

    2006-05-01

    The optical characteristics of one multimode fiber (MMF)-hollow core fiber (HCF)-structure when a nanofilm is deposited on it has been theoretically and experimentally studied. The electrostatic self-assembly method has been used as the deposition technique, and the polymers chosen are polydiallyldimethylammonium and Poly R-478. Two different types of HCF have been used for the fabrication of the devices: 10/150 and 50/150 µm inner and outer diameters, respectively. Depending on several design parameters, the transmitted optical-power characteristic of the device experiences important changes that could be interesting towards development of several practical optical devices. The length and thickness of the HCF segment, the refractive index of the material deposited, the angle of the light when it reach the HCF section, and the wavelength of the light source will be analyzed.

  18. Alkyl-terminated Si(111) surfaces: A high-resolution, core level photoelectron spectroscopy study

    SciTech Connect

    Terry, J.; Linford, M.R.; Wigren, C.; Cao, R.; Pianetta, P.; Chidsey, C.E.

    1999-01-01

    The bonding of alkyl monolayers to Si(111) surfaces has been studied with high-resolution core level photoelectron spectroscopy (PES). Two very different wet-chemical methods have been used to prepare the alkyl monolayers: (i) Olefin insertion into the H{endash}Si bond of the H{endash}Si(111) surface, and (ii) replacement of Cl on the Cl{endash}Si(111) surface by an alkyl group from an alkyllithium reagent. In both cases, PES has revealed a C 1s component shifted to lower binding energy and a Si 2p component shifted to higher binding energy. Both components are attributed to the presence of a C{endash}Si bond at the interface. Along with photoelectron diffraction data [Appl. Phys. Lett. {bold 71}, 1056, (1997)], these data are used to show that these two synthetic methods can be used to functionalize the Si(111) surface. {copyright} {ital 1999 American Institute of Physics.}

  19. Studies of lunar regolith dynamics using measurements of cosmogenic radionuclides in lunar rocks, soils and cores

    NASA Technical Reports Server (NTRS)

    Fruchter, J. S.; Reeves, J. H.; Evans, J. C.; Perkins, R. W.

    1982-01-01

    The present investigation is concerned with two types of measurements. The first deals with the use of Al-26 to define regolith gardening processes which have occurred in the upper portion of the lunar cores that were collected both by the deep drilling and drive tube operations. The second portion of the study involves the use of Mn-53 and Al-26 concentrations to determine the surface exposure histories of individual rocks over the past ten million years. It is found that during the past two million years, 15011 has had a history of simple gardening with an accumulation rate of 2 cm/m.y. The Apollo 15 Station 2 boulder appears to have been in place for about five million years. The 'shadowed' soil (75237) shows a shielding effect of about 40%. The Apollo 16 Station 9 boulder appears to have been in place for about four million years and thus is apparently not related to the South Ray Crater event.

  20. Preliminary core design studies for the advanced burner reactor over a wide range of conversion ratios.

    SciTech Connect

    Hoffman, E. A.; Yang, W. S.; Hill, R. N.; Nuclear Engineering Division

    2008-05-05

    A consistent set of designs for 1000 MWt commercial-scale sodium-cooled Advance Burner Reactors (ABR) have been developed for both metal and oxide-fueled cores with conversion ratios from breakeven (CR=1.0) to fertile-free (CR=0.0). These designs are expected to satisfy thermal and irradiation damage limits based on the currently available data. The very low conversion ratio designs require fuel that is beyond the current fuel database, which is anticipated to be qualified by and for the Advanced Burned Test Reactor. Safety and kinetic parameters were calculated, but a safety analysis was not performed. Development of these designs was required to achieve the primary goal of this study, which was to generate representative fuel cycle mass flows for system studies of ABRs as part of the Global Nuclear Energy Partnership (GNEP). There are slight variations with conversion ratio but the basic ABR configuration consists of 144 fuel assemblies and between 9 and 22 primary control assemblies for both the metal and oxide-fueled cores. Preliminary design studies indicated that it is feasible to design the ABR to accommodate a wide range of conversion ratio by employing different assembly designs and including sufficient control assemblies to accommodate the large reactivity swing at low conversion ratios. The assemblies are designed to fit within the same geometry, but the size and number of fuel pins within each assembly are significantly different in order to achieve the target conversion ratio while still satisfying thermal limits. Current irradiation experience would allow for a conversion ratio of somewhat below 0.75. The fuel qualification for the first ABR should expand this experience to allow for much lower conversion ratios and higher bunrups. The current designs were based on assumptions about the performance of high and very high enrichment fuel, which results in significant uncertainty about the details of the designs. However, the basic fuel cycle performance

  1. Using Animations to Study the Formation of Gas Giant Planets via the Core Accretion Model

    NASA Astrophysics Data System (ADS)

    Hubickyj, O.; Lissauer, J. J.; Bodemheimer, P.; D'Angelo, G.

    2009-12-01

    With the ever increasing number of extrasolar planets being discovered (373 as of 8/13/09 quoted by The Extrasolar Planets Encyclopedia: exoplanet.eu) and the recognition of their diverse nature it is very important to understand the formation processes of the gas giant planets. The core accretion model has successfully explained many features of the formation of gas giant planets in the Solar System (Pollack et al. 1996, Hubickyj et al. 2005) and it has provided an explanation of the characteristics of exoplanets. One example is the observed frequency of planets around stars with a high metal content (e.g. Kornet et al. 2005, Valenti and Fischer 2008). Improvements to the input physics to our computer model have resulted in the very important result that gas giant planets (i.e. Jupiter) can form via the core accretion model on a timescale that agrees with observations of protoplanetary disks (Hillenbrand 2008). These observations set the formation time to about 3 to 5 million years. We will present our recent results (Hubickyj et al. 2005,Lissauer et al. 2009) in the form of animations. Our models generate a substantial amount of data. Having published plots of the important values of our study: mass and radius growth, luminosity, and accretion rates as a function of time, we are now ready to study the second tier of information from our recorded data. We examine the energy profiles within the envelope as it evolves, the location and changes of the convective layers, and the location of the mass deposited by the planetesimals in the envelope as the protoplanet evolves. We find that by animating the data we can study the internal processes in the growing envelope of the protoplanet. The qualitative nature of the processes in the protoplanetary envelope is easily discerned in these animations and a deeper insight to the core accretion processes in the gas giant planets is gained. Hillenbrand, L. A. 2008. Disk-dispersal and planet-formation timescales. Physica

  2. An analytical study of volatile metallic fission product release from very high temperature gas-cooled reactor fuel and core

    SciTech Connect

    Mitake, S.; Okamoto, F.

    1988-04-01

    Release characteristics of volatile metallic fission products from the coated fuel particle and the reactor core for a very high temperature gas-cooled reactor during its power operation has been studied using numerical analysis. A computer code FORNAX, based on Fick's diffusion law and the evaporation mass transfer relation, has been developed, which considers, in particular, distribution and time histories of power density, fuel temperature, and failed and degraded fuel particle fractions in the core. Applicability of the code to evaluate the core design has been shown and the following have been indicated on the release of cesium from the reactor: 1. The release from the intact fuel particles by diffusion through their intact coatings shows larger contribution in the total core release at higher temperature. 2. The diffusion release from the intact particle is governed not only by the diffusion in the silicon carbide layer but also by that in the fuel kernel.

  3. Experimental and Analytic Study on the Core Bypass Flow in a Very High Temperature Reactor

    SciTech Connect

    Richard Schultz

    2012-04-01

    Core bypass flow has been one of key issues in the very high temperature reactor (VHTR) design for securing core thermal margins and achieving target temperatures at the core exit. The bypass flow in a prismatic VHTR core occurs through the control element holes and the radial and axial gaps between the graphite blocks for manufacturing and refueling tolerances. These gaps vary with the core life cycles because of the irradiation swelling/shrinkage characteristic of the graphite blocks such as fuel and reflector blocks, which are main components of a core's structure. Thus, the core bypass flow occurs in a complicated multidimensional way. The accurate prediction of this bypass flow and counter-measures to minimize it are thus of major importance in assuring core thermal margins and securing higher core efficiency. Even with this importance, there has not been much effort in quantifying and accurately modeling the effect of the core bypass flow. The main objectives of this project were to generate experimental data for validating the software to be used to calculate the bypass flow in a prismatic VHTR core, validate thermofluid analysis tools and their model improvements, and identify and assess measures for reducing the bypass flow. To achieve these objectives, tasks were defined to (1) design and construct experiments to generate validation data for software analysis tools, (2) determine the experimental conditions and define the measurement requirements and techniques, (3) generate and analyze the experimental data, (4) validate and improve the thermofluid analysis tools, and (5) identify measures to control the bypass flow and assess its performance in the experiment.

  4. Burn Survivors' Experience of Core Outcomes during Return to Life: a Qualitative Study

    PubMed Central

    Zamanzadeh, Vahid; Valizadeh, Leila; Lotfi, Mojgan; Salehi, Feridoon

    2014-01-01

    Introduction: Burn is one of the main and common health problems that face the victims with significant challenges in their lives. The main purpose of caring and rehabilitating these people is returning them to their previous life situation. Thus, the present study was conducted with the purpose of determining the experience of burn survivors with regard to returning to life in order to be able to obtain new concepts of acceptable implications in the present cultural and religious context. Methods: The present study is a qualitative study that was conducted using qualitative content analysis and in-depth unstructured interviews with 15 burn survivors in 2012 and 2013 in Tabriz. Results: During the process of qualitative analysis, the content of the category "balance", as the core essence of the experience of participants, was extracted according to three sub-categories: a- the physical integration (physiological stability, saving the affected limb), b-connecting to the life stream (self-care, getting accustomed, normalization), and c- return to the existence (sense of inner satisfaction and excellence). Conclusion: The results of this study confirmed the physical, psychological and social scales introduced by other studies. Also proposed the concept "return to the existence", that can be measured by the emergence of a sense of inner satisfaction and excellence in the individual, as one of the key and determinant scales in returning the victims of burn to life. PMID:25717453

  5. Ten-core versus 16-core transrectal ultrasonography guided prostate biopsy for detection of prostatic carcinoma: a prospective comparative study in Indian population

    PubMed Central

    Prakash, V. Surya; Mohan, G. Chandra; Krishnaiah, S. Venkata; Vijaykumar, V.; Babu, G. Ramesh; Reddy, G. Vijaya Bhaskar; Mahaboob, V. S.

    2013-01-01

    Purpose: To compare the cancer detection rate in patients with raised serum prostate-specific antigen (PSA) or abnormal digital rectal examination (DRE) results between the 10-core and the 16-core biopsy techniques in an Indian population. Methods: Between November 2010 and November 2012, 95 men aged >50 years who presented to the Urology Department with lower urinary tract symptoms, elevated serum PSA, and/or abnormal DRE findings underwent transrectal ultrasonography (TRUS)-guided prostate biopsy. A total of 53 patients underwent 10-core biopsy and 42 patients underwent 16-core biopsy. Results: Of the 53 men in the 10-core group, 8 had cancer, whereas in the 16-core biopsy group, 23 of 42 men had cancer. Detection of prostate cancer was significantly higher in patients who underwent 16-core biopsy than in those who underwent 10-core biopsy (P<0.001). Among the 95 men, 44 men had abnormal DRE findings (46.3%), of whom 23 showed cancer (52.27%). Of 51 men with normal DRE findings and elevated PSA, 8 men had malignancy with a cancer detection rate of 15.68%. Among 20 men with PSA between 4.1 and 10 ng/mL, 2 (10%) had cancer. In 31 men with PSA between 10.1 and 20 ng/mL, 3 cancers (9.67%) were detected, and in 44 men with PSA >20 ng/mL, 26 cancers were detected (59.09%). Conclusions: The cancer detection rate with 16-core TRUS-guided biopsy is significantly higher than that with 10-core biopsy (54.76% vs. 15.09%, P<0.001). In patients with both normal and abnormal DRE findings, 16-core biopsy has a better detection rate than the 10-core biopsy protocol. With increasing PSA, there is a high rate of detection of prostate cancer in both 10-core and 16-core biopsy patients. PMID:24392441

  6. Study on micro-bend light transmission performance of novel liquid-core optical fiber

    NASA Astrophysics Data System (ADS)

    Ma, Junyan; Zhao, Zhimin; Wang, Kaisheng; Guo, Linfeng

    2007-01-01

    With the increasing development of material technology and electronic integration technology, optical fiber and its using in smart structure have become hot in the field of material research. And liquid-core optical fiber is a special kind of optical fiber, which is made using liquid material as core and polymer material as optical layer and protective covering, and it has the characteristics of large core diameter, high numerical aperture, large-scope and efficient spectrum transmission and long life for using. So the liquid-core optical fiber is very suitable for spectrum cure, ultraviolet solidification, fluorescence detection, criminal investigation and evidence obtainment, etc, and especially as light transfer element in some new structures for the measurement of some signals, such as concentration, voltage, temperature, light intensity and so on. In this paper, the novel liquid-core optical fiber is self-made, and then through the test of its light transmission performance in free state, the relation between axial micro-bend and light-intensity loss are presented. When the liquid-core optical fiber is micro-bent axially, along with the axial displacement's increase, output power of light is reducing increasingly, and approximately has linear relation to micro-displacement in a range. According to the results liquid-core fiber-optic micro-bend sensor can be designed to measure micro-displacement of the tested objects. Experimental data and analysis provide experimental basis for further application of liquid-core optical fiber.

  7. A comparative theoretical study on core-hole excitation spectra of azafullerene and its derivatives.

    PubMed

    Deng, Yunfeng; Gao, Bin; Deng, Mingsen; Luo, Yi

    2014-03-28

    The core-hole excitation spectra-near-edge x-ray absorption spectroscopy (NEXAFS), x-ray emission spectroscopy (XES), and x-ray photoelectron spectroscopy (XPS) shake-up satellites have been simulated at the level of density functional theory for the azafullerene C59N and its derivatives (C59N)(+), C59HN, (C59N)2, and C59N-C60, in which the XPS shake-up satellites were simulated using our developed equivalent core hole Kohn-Sham (ECH-KS) density functional theory approach [B. Gao, Z. Wu, and Y. Luo, J. Chem. Phys. 128, 234704 (2008)] which aims for the study of XPS shake-up satellites of large-scale molecules. Our calculated spectra are generally in good agreement with available experimental results that validates the use of the ECH-KS method in the present work. The nitrogen K-edge NEXAFS, XES, and XPS shake-up satellites spectra in general can be used as fingerprints to distinguish the azafullerene C59N and its different derivatives. Meanwhile, different carbon K-edge spectra could also provide detailed information of (local) electronic structures of different molecules. In particular, a peak (at around 284.5 eV) in the carbon K-edge NEXAFS spectrum of the heterodimer C59N-C60 is confirmed to be related to the electron transfer from the C59N part to the C60 part in this charge-transfer complex. PMID:24697438

  8. A comparative theoretical study on core-hole excitation spectra of azafullerene and its derivatives

    SciTech Connect

    Deng, Yunfeng; Gao, Bin; Deng, Mingsen; Luo, Yi

    2014-03-28

    The core-hole excitation spectra—near-edge x-ray absorption spectroscopy (NEXAFS), x-ray emission spectroscopy (XES), and x-ray photoelectron spectroscopy (XPS) shake-up satellites have been simulated at the level of density functional theory for the azafullerene C{sub 59}N and its derivatives (C{sub 59}N){sup +}, C{sub 59}HN, (C{sub 59}N){sub 2}, and C{sub 59}N–C{sub 60}, in which the XPS shake-up satellites were simulated using our developed equivalent core hole Kohn-Sham (ECH-KS) density functional theory approach [B. Gao, Z. Wu, and Y. Luo, J. Chem. Phys. 128, 234704 (2008)] which aims for the study of XPS shake-up satellites of large-scale molecules. Our calculated spectra are generally in good agreement with available experimental results that validates the use of the ECH-KS method in the present work. The nitrogen K-edge NEXAFS, XES, and XPS shake-up satellites spectra in general can be used as fingerprints to distinguish the azafullerene C{sub 59}N and its different derivatives. Meanwhile, different carbon K-edge spectra could also provide detailed information of (local) electronic structures of different molecules. In particular, a peak (at around 284.5 eV) in the carbon K-edge NEXAFS spectrum of the heterodimer C{sub 59}N–C{sub 60} is confirmed to be related to the electron transfer from the C{sub 59}N part to the C{sub 60} part in this charge-transfer complex.

  9. Getting to the Core: Using Digital Resources to Enhance Content-Based Literacy in the Social Studies

    ERIC Educational Resources Information Center

    Berson, Ilene R.; Berson, Michael J.

    2013-01-01

    With the implementation of the Common Core State Standards for English Language Arts and Literacy in History/Social Studies, Science, and Technical Subjects, teachers across the United States are expanding their integrated approach to social studies instruction and literacy studies. They are challenged to infuse text and narratives linked to…

  10. Theoretical study of geometry relaxation following core excitation: H2O, NH3, and CH4

    NASA Astrophysics Data System (ADS)

    Takahashi, Osamu; Kunitake, Naoto; Takaki, Saya

    2015-10-01

    Single core-hole (SCH) and double core-hole excited state molecular dynamics (MD) calculations for neutral and cationic H2O, NH3, and CH4 have been performed to examine geometry relaxation after core excitation. We observed faster X-H (X = C, N, O) bond elongation for the core-ionized state produced from the valence cationic molecule and the double-core-ionized state produced from the ground and valence cationic molecules than for the first resonant SCH state. Using the results of SCH MD simulations of the ground and valence cationic molecules, Auger decay spectra calculations were performed. We found that fast bond scission leads to peak broadening of the spectra.

  11. Photoluminescence study of high density Si quantum dots with Ge core

    NASA Astrophysics Data System (ADS)

    Kondo, K.; Makihara, K.; Ikeda, M.; Miyazaki, S.

    2016-01-01

    Si quantum dots (Si-QDs) with Ge core were self-assembled on thermally grown SiO2 from alternate thermal decomposition of pure SiH4 and GeH4 diluted with He. When the sample was excited by the 979 nm line of a semiconductor laser, fairly broad photoluminescence (PL) spectra in the region of 0.6-0.8 eV were observed at room temperature. The observed PL spectra suggested that radiative recombination of photo-generated carriers through quantized states of Ge core is the dominant pathway for the emission from the dots, reflecting the type II energy band discontinuity between the Si clad and Ge core. We also found that P-δ doping to Ge core plays an important role in recombination through the quantized states in the valence band of Ge core and P donor levels.

  12. Influence of rigid core permittivity and double layer polarization on the electrophoresis of a soft particle: A numerical study

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, S.; De, Simanta

    2016-01-01

    The nonlinear electrophoresis of a soft particle with a polarizable uncharged rigid core coated with a polyelectrolyte layer is studied. Due to the coupled nature of the governing electrokinetic equations, a numerical approach is adopted. Our numerical solutions are in good agreement with the existing experimental and theoretical results for a particle with a non-polarizable core when the impacts of the nonlinear effects are low. The induced surface potential of the dielectric rigid core has an impact on the soft particle electrophoresis. The combined effects of the solid polarization of the core and double layer polarization have not been addressed previously in the context of soft particle electrophoresis. We have found that both these effects create retardation on the electrophoresis and are significant when the applied electric field is not weak. The double layer polarization is significant when the Debye length is in the order of the particle size. The range of the applied electric field for which the electrophoretic velocity of a soft particle with a non-polarizable core varies linearly with the applied electric field may create a nonlinear variation in electrophoretic velocity when the core is considered to be polarizable.

  13. Paleomagnetic studies of Carboniferous and Permian in the U. K. Southern North Sea: Core orientation, paleocurrent analysis, and diagenetic application

    SciTech Connect

    Turner, P. ); Hartley, A.J. )

    1991-03-01

    The U.K. southern North Sea is a major gas province with production from Carboniferous and Permian reservoirs. It was a foreland basin in Carboniferous times uplifted to form a Lower Permian desert basin and subsequently deeply buried during the Mesozoic. Paleomagnetic methods have been used for burial analysis, core orientation, and paleocurrent studies. VRM is shown to be of only limited value for core orientation; problems relating to drilling effects and deflection by ChRM will be discussed. Detailed thermal demagnetization studies are most valuable. Blocking temperature spectra can be related to burial history curves, and ChRM directions isolated and compared with Carboniferous and Permian reference directions. ChRM is a valuable parameter for core orientation and thus paleocurrent studies. Examples will be shown from the Carboniferous and Lower Permian.

  14. Turbulence coefficients and stability studies for the coaxial flow or dissimiliar fluids. [gaseous core nuclear reactors

    NASA Technical Reports Server (NTRS)

    Weinstein, H.; Lavan, Z.

    1975-01-01

    Analytical investigations of fluid dynamics problems of relevance to the gaseous core nuclear reactor program are presented. The vortex type flow which appears in the nuclear light bulb concept is analyzed along with the fluid flow in the fuel inlet region for the coaxial flow gaseous core nuclear reactor concept. The development of numerical methods for the solution of the Navier-Stokes equations for appropriate geometries is extended to the case of rotating flows and almost completes the gas core program requirements in this area. The investigations demonstrate that the conceptual design of the coaxial flow reactor needs further development.

  15. A comparative study of the impact properties of sandwich materials with different cores

    NASA Astrophysics Data System (ADS)

    Ramakrishnan, K. R.; Shankar, K.; Viot, P.; Guerard, S.

    2012-08-01

    Sandwich panels are made of two high strength skins bonded to either side of a light weight core and are used in applications where high stiffness combined with low structural weight is required. The purpose of this paper is to compare the mechanical response of several sandwich panels whose core materials are different. Sandwich panels with glass fibre-reinforced polymer face sheets were used, combined with five different cores; polystyrene foam, polypropylene honeycomb, two different density Balsa wood and Cork. All specimens were subjected to low velocity impact and their structural response (Force-displacement curves) were compared to quasistatic response of the panel tested using an hemispherical indenter.

  16. Fractographic study of the behavior of different ceramic veneers on full coverage crowns in relation to supporting core materials

    PubMed Central

    Agustín-Panadero, Rubén; Román-Rodriguez, Juan L.; Solá-Ruíz, María F.; Granell-Ruíz, María; Fons-Font, Antonio

    2013-01-01

    Objectives: To observe porcelain veneer behavior of zirconia and metal-ceramic full coverage crowns when subjected to compression testing, comparing zirconia cores to metal cores. Study Design: The porcelain fracture surfaces of 120 full coverage crowns (60 with a metal core and 60 with a zirconia core) subjected to static load (compression) testing were analyzed. Image analysis was performed using macroscopic processing with 8x and 12x enlargement. Five samples from each group were prepared and underwent scanning electron microscope (SEM) analysis in order to make a fractographic study of fracture propagation in the contact area and composition analysis in the most significant areas of the specimen. Results: Statistically significant differences in fracture type (cohesive or adhesive) were found between the metal-ceramic and zirconia groups: the incidence of adhesive fracture was seen to be greater in metal-ceramic groups (92%) and cohesive fracture was more frequent in zirconium oxide groups (72%). The fracture propagation pattern was on the periphery of the contact area in the full coverage crown restorations selected for fractographic study. Conclusions: The greater frequency of cohesive fracture in restorations with zirconia cores indicates that their behavior is inadequate compared to metal-ceramic restorations and that further research is needed to improve their clinical performance. Key words:Zirconia, zirconium oxide, fractography, composition, porcelain veneers, fracture, cohesive, adhesive. PMID:24455092

  17. High-resolution core-level photoemission study of dense Pb overlayers on Si(111)

    NASA Astrophysics Data System (ADS)

    Choi, Won Hoon; Kim, Keun Su; Yeom, Han Woong

    2008-11-01

    Structure and bonding configuration of dense Pb overlayers on the Si(111) surface have been studied by low-energy-electron diffraction and high-resolution photoelectron spectroscopy using synchrotron radiation. Several representative phases in its devil’s staircase phase diagram have been systematically investigated by varying the Pb coverage at 200-300 K. Pb5d photoelectron spectra indicate that there exist two distinct bonding configurations of Pb, which are interpreted as the hollow and on-top (T1) sites of the structure models proposed earlier. In case of surface Si atoms, mainly two different bonding environments are revealed by surface Si2p components for the low-density 7×3 phase. These can be assigned to T1 and modified on-top (T1') sites surrounding hollow-site adatoms. As the coverage increases, the minority site T1 converts to T1' making the topmost Si layer have a unique bonding configuration. This behavior is also consistent with the structure models. The temperature-dependent study reveals that the 7×3 phase undergoes a reversible phase transition into a 1×1 phase. This phase transition induces no significant change in Pb core levels but a marginal increase in the Si2p component for the T1' sites. We suggest a plausible scenario of the phase transition based on the structure model with 1.2 monolayer Pb and the active diffusion of hollow-site adatoms.

  18. Preliminary Results of a Multi-Proxy Lake Sediment Core Study in East-Central France

    NASA Astrophysics Data System (ADS)

    Misner, T.; Meyers, S.; Rosenmeier, M.; Strano, S.; Straffin, E.

    2008-12-01

    This paper presents the preliminary results of a multi-proxy study of natural and human-induced changes in the Burgundian environment, as recorded in the sediment geochemistry of three small freshwater basins within the Arroux River Valley, east-central France. Accelerator mass spectrometry radiocarbon dates constrain the age of core material collected from the basins, and indicate that these mill and farm ponds were constructed by at least 1200 A.D. The pond sediments are predominantly massive, organic-rich muds that contain discrete sand and gravel lenses likely related to episodic flooding and/or basin drainage. In this study, continuous X-ray fluorescence (XRF) scanning is used to quantify bulk geochemical variability throughout the lake sediment cores, and to investigate specific elemental proxies for paleoenvironmental change (detrital flux, biogenic flux, and redox state). The high-resolution XRF data are supplemented by sediment magnetic susceptibility measurements, and organic matter concentration as determined by loss on ignition. These records demonstrate a general increase in detrital sediment input from 1200 to 1300 A.D., during a period of known regional agricultural expansion. We infer these changes to be the consequence of increased catchment soil erosion and material flux to the water bodies. The data also suggest changes in mill and farm pond primary productivity, also related to soil erosion and changing transport of soil nutrients to the basins. Near the onset of the Little Ice Age (ca. 1500 A.D.) pond productivity reductions are apparent, likely indicating colder climates. These mill and farm pond sedimentary archives, in conjunction with historic records, can be used to better understand past land management strategies. Furthermore, historically documented landscape changes can be examined within the context of prevailing climatic conditions over the last ~800 years in an effort to establish future best management practices and the most

  19. The Expanded Core Curriculum at the Indiana School for the Blind and Visually Impaired: A Case Study

    ERIC Educational Resources Information Center

    Ringwalt, Gail Mulholland

    2013-01-01

    This case study investigated how the Expanded Core Curriculum (ECC) was taught to high school students who are blind or visually impaired at the Indiana School for the Blind and Visually Impaired (ISBVI). The study focused on three students pursing different academic tracks with varying degrees of vision. The students were observed throughout…

  20. Interaction of sigma 70 with Escherichia coli RNA polymerase core enzyme studied by surface plasmon resonance.

    PubMed

    Ferguson, A L; Hughes, A D; Tufail, U; Baumann, C G; Scott, D J; Hoggett, J G

    2000-09-22

    The interaction between the core form of bacterial RNA polymerases and sigma factors is essential for specific promoter recognition, and for coordinating the expression of different sets of genes in response to varying cellular needs. The interaction between Escherichia coli core RNA polymerase and sigma 70 has been investigated by surface plasmon resonance. The His-tagged form of sigma 70 factor was immobilised on a Ni2+-NTA chip for monitoring its interaction with core polymerase. The binding constant for the interaction was found to be 1.9x10(-7) M, and the dissociation rate constant for release of sigma from core, in the absence of DNA or transcription, was 4x10(-3) s(-1), corresponding to a half-life of about 200 s. PMID:11007979

  1. Ab Initio Study of 40Ca with an Importance Truncated No-Core Shell Model

    SciTech Connect

    Roth, R; Navratil, P

    2007-05-22

    We propose an importance truncation scheme for the no-core shell model, which enables converged calculations for nuclei well beyond the p-shell. It is based on an a priori measure for the importance of individual basis states constructed by means of many-body perturbation theory. Only the physically relevant states of the no-core model space are considered, which leads to a dramatic reduction of the basis dimension. We analyze the validity and efficiency of this truncation scheme using different realistic nucleon-nucleon interactions and compare to conventional no-core shell model calculations for {sup 4}He and {sup 16}O. Then, we present the first converged calculations for the ground state of {sup 40}Ca within no-core model spaces including up to 16{h_bar}{Omega}-excitations using realistic low-momentum interactions. The scheme is universal and can be easily applied to other quantum many-body problems.

  2. Electron Cryotomography Studies of Maturing HIV-1 Particles Reveal the Assembly Pathway of the Viral Core

    PubMed Central

    Woodward, Cora L.; Cheng, Sarah N.

    2014-01-01

    ABSTRACT To better characterize the assembly of the HIV-1 core, we have used electron cryotomography (ECT) to image infected cells and the viral particles cryopreserved next to them. We observed progressive stages of virus assembly and egress, including flower-like flat Gag lattice assemblies, hemispherical budding profiles, and virus buds linked to the plasma membrane via a thin membrane neck. The population of budded viral particles contains immature, maturation-intermediate, and mature core morphologies. Structural characteristics of the maturation intermediates suggest that the core assembly pathway involves the formation of a CA sheet that associates with the condensed ribonucleoprotein (RNP) complex. Our analysis also reveals a correlation between RNP localization within the viral particle and the formation of conical cores, suggesting that the RNP helps drive conical core assembly. Our findings support an assembly pathway for the HIV-1 core that begins with a small CA sheet that associates with the RNP to form the core base, followed by polymerization of the CA sheet along one side of the conical core toward the tip, and then closure around the body of the cone. IMPORTANCE During HIV-1 assembly and release, the Gag polyprotein is organized into a signature hexagonal lattice, termed the immature lattice. To become infectious, the newly budded virus must disassemble the immature lattice by proteolyzing Gag and then reassemble the key proteolytic product, the structural protein p24 (CA), into a distinct, mature hexagonal lattice during a process termed maturation. The mature HIV-1 virus contains a conical capsid that encloses the condensed viral genome at its wide base. Mutations or small molecules that interfere with viral maturation also disrupt viral infectivity. Little is known about the assembly pathway that results in the conical core and genome encapsidation. Here, we have used electron cryotomography to structurally characterize HIV-1 particles that are

  3. A first-principles core-level XPS study on the boron impurities in germanium crystal

    SciTech Connect

    Yamauchi, Jun; Yoshimoto, Yoshihide; Suwa, Yuji

    2013-12-04

    We systematically investigated the x-ray photoelectron spectroscopy (XPS) core-level shifts and formation energies of boron defects in germanium crystals and compared the results to those in silicon crystals. Both for XPS core-level shifts and formation energies, relationship between defects in Si and Ge is roughly linear. From the similarity in the formation energy, it is expected that the exotic clusters like icosahedral B12 exist in Ge as well as in Si.

  4. A first-principles core-level XPS study on the boron impurities in germanium crystal

    NASA Astrophysics Data System (ADS)

    Yamauchi, Jun; Yoshimoto, Yoshihide; Suwa, Yuji

    2013-12-01

    We systematically investigated the x-ray photoelectron spectroscopy (XPS) core-level shifts and formation energies of boron defects in germanium crystals and compared the results to those in silicon crystals. Both for XPS core-level shifts and formation energies, relationship between defects in Si and Ge is roughly linear. From the similarity in the formation energy, it is expected that the exotic clusters like icosahedral B12 exist in Ge as well as in Si.

  5. Deep Chandra study of the truncated cool core of the Ophiuchus cluster

    NASA Astrophysics Data System (ADS)

    Werner, N.; Zhuravleva, I.; Canning, R. E. A.; Allen, S. W.; King, A. L.; Sanders, J. S.; Simionescu, A.; Taylor, G. B.; Morris, R. G.; Fabian, A. C.

    2016-08-01

    We present the results of a deep (280 ks) Chandra observation of the Ophiuchus cluster, the second-brightest galaxy cluster in the X-ray sky. The cluster hosts a truncated cool core, with a temperature increasing from kT~1 keV in the core to kT~9 keV at r~30 kpc. Beyond r~30 kpc the intra-cluster medium (ICM) appears remarkably isothermal. The core is dynamically disturbed with multiple sloshing induced cold fronts, with indications for both Rayleigh-Taylor and Kelvin-Helmholtz instabilities. The sloshing is the result of the strongly perturbed gravitational potential in the cluster core, with the central brightest cluster galaxy (BCG) being displaced southward from the global center of mass. The residual image reveals a likely subcluster south of the core at the projected distance of r~280 kpc. The cluster also harbors a likely radio phoenix, a source revived by adiabatic compression by gas motions in the ICM. Even though the Ophiuchus cluster is strongly dynamically active, the amplitude of density fluctuations outside of the cooling core is low, indicating velocities smaller than ~100 km/s. The density fluctuations might be damped by thermal conduction in the hot and remarkably isothermal ICM, resulting in our underestimate of gas velocities. We find a surprising, sharp surface brightness discontinuity, that is curved away from the core, at r~120 kpc to the southeast of the cluster center. We conclude that this feature is most likely due to gas dynamics associated with a merger and not a result of an extraordinary active galactic nucleus (AGN) outburst. The cooling core lacks any observable X-ray cavities and the AGN only displays weak, point-like radio emission, lacking lobes or jets, indicating that currently it may be largely dormant. The lack of strong AGN activity may be due to the bulk of the cooling taking place offset from the central supermassive black hole.

  6. THE EFFECT OF SELF-SET GRADE GOALS AND CORE SELF-EVALUATIONS ON ACADEMIC PERFORMANCE: A DIARY STUDY.

    PubMed

    Bipp, Tanja; Kleingeld, Ad; Van Den Tooren, Marieke; Schinkel, Sonja

    2015-12-01

    The aim of this diary study was to examine the effect of self-set grade goals and core self-evaluations on academic performance. Data were collected among 59 university students (M age = 18.4 yr., SD = 0.8) in a 2-wk. exam period on up to five exam days. Multilevel analyses revealed that the individual grade goals students set for their exams were positively related to the grades they obtained for these exams. However, the goal-performance relationship only applied to students scoring high on core self-evaluations. The results of this study contribute to the understanding of the effect of self-set grade goals and core self-evaluations on academic performance and imply important practical applications to enhance academic performance. PMID:26595291

  7. Perceived pros and cons of smoking and quitting in hard-core smokers: a focus group study

    PubMed Central

    2014-01-01

    Background In the last decade, so-called hard-core smokers have received increasing interest in research literature. For smokers in general, the study of perceived costs and benefits (or ‘pros and cons’) of smoking and quitting is of particular importance in predicting motivation to quit and actual quitting attempts. Therefore, this study aims to gain insight into the perceived pros and cons of smoking and quitting in hard-core smokers. Methods We conducted 11 focus group interviews among current hard-core smokers (n = 32) and former hard-core smokers (n = 31) in the Netherlands. Subsequently, each participant listed his or her main pros and cons in a questionnaire. We used a structural procedure to analyse the data obtained from the group interviews and from the questionnaires. Results Using the qualitative data of both the questionnaires and the transcripts, the perceived pros and cons of smoking and smoking cessation were grouped into 6 main categories: Finance, Health, Intrapersonal Processes, Social Environment, Physical Environment and Food and Weight. Conclusions Although the perceived pros and cons of smoking in hard-core smokers largely mirror the perceived pros and cons of quitting, there are some major differences with respect to weight, social integration, health of children and stress reduction, that should be taken into account in clinical settings and when developing interventions. Based on these findings we propose the ‘Distorted Mirror Hypothesis’. PMID:24548463

  8. A Numerical Study on the Effect of Facesheet-Core Disbonds on the Buckling Load of Curved Honeycomb Sandwich Panels

    NASA Technical Reports Server (NTRS)

    Pineda, Evan J.; Myers, David E.; Bednarcyk, Brett A.; Krivanek, Thomas M.

    2015-01-01

    A numerical study on the effect of facesheet-core disbonds on the post-buckling response of curved honeycomb sandwich panels is presented herein. This work was conducted as part of the development of a damage tolerance approach for the next-generation Space Launch System heavy lift vehicle payload fairing. As such, the study utilized full-scale fairing barrel segments as the structure of interest. The panels were composed of carbon fiber reinforced polymer facesheets and aluminum honeycomb core. The panels were analyzed numerically using the finite element method. Facesheet and core nodes in a predetermined circular region were detached to simulate a disbond induced via low-speed impact between the outer mold line facesheet and honeycomb core. Surface-to-surface contact in the disbonded region was invoked to prevent interpenetration of the facesheet and core elements. The diameter of this disbonded region was varied and the effect of the size of the disbond on the post-buckling response was observed. A significant change in the slope of the edge load-deflection response was used to determine the onset of global buckling and corresponding buckling load.

  9. Study of muons near shower cores at sea level using the E594 neutrino detector

    NASA Technical Reports Server (NTRS)

    Goodman, J. A.; Gupta, S. C.; Freudenreich, H.; Sivaprasad, K.; Tonwar, S. C.; Yodh, G. B.; Ellsworth, R. W.; Goodman, M. C.; Bogert, D.; Burnstein, R.

    1985-01-01

    The E594 neutrino detector has been used to study the lateral distribution of muons of energy 3 GeV near shower cores. The detector consists of a 340 ton fine grain calorimeter with 400,000 cells of flash chamber and dimensions of 3.7 m x 20 m x 3.7 m (height). The average density in the calorimeter is 1.4 gm/sq cm, and the average Z is 21. The detector was triggered by four 0.6 sq m scintillators placed immediately on the top of the calorimeter. The trigger required at least two of these four counters. The accompanying extensive air showers (EAS) was sampled by 14 scintillation counters located up to 15 m from the calorimeter. Several off line cuts have been applied to the data. Demanding five particles in at least two of the trigger detectors, a total of 20 particles in all of them together, and an arrival angle for the shower 450 deg reduced the data sample to 11053 events. Of these in 4869 cases, a computer algorithm found at least three muons in the calorimeter.

  10. Parametric study of flow patterns behind the standing accretion shock wave for core-collapse supernovae

    SciTech Connect

    Iwakami, Wakana; Nagakura, Hiroki; Yamada, Shoichi

    2014-05-10

    In this study, we conduct three-dimensional hydrodynamic simulations systematically to investigate the flow patterns behind the accretion shock waves that are commonly formed in the post-bounce phase of core-collapse supernovae. Adding small perturbations to spherically symmetric, steady, shocked accretion flows, we compute the subsequent evolutions to find what flow pattern emerges as a consequence of hydrodynamical instabilities such as convection and standing accretion shock instability for different neutrino luminosities and mass accretion rates. Depending on these two controlling parameters, various flow patterns are indeed realized. We classify them into three basic patterns and two intermediate ones; the former includes sloshing motion (SL), spiral motion (SP), and multiple buoyant bubble formation (BB); the latter consists of spiral motion with buoyant-bubble formation (SPB) and spiral motion with pulsationally changing rotational velocities (SPP). Although the post-shock flow is highly chaotic, there is a clear trend in the pattern realization. The sloshing and spiral motions tend to be dominant for high accretion rates and low neutrino luminosities, and multiple buoyant bubbles prevail for low accretion rates and high neutrino luminosities. It is interesting that the dominant pattern is not always identical between the semi-nonlinear and nonlinear phases near the critical luminosity; the intermediate cases are realized in the latter case. Running several simulations with different random perturbations, we confirm that the realization of flow pattern is robust in most cases.

  11. Numerical Models of Starburst Galaxies: A Study of Outflows and ISM Morphology in Galactic Cores

    NASA Astrophysics Data System (ADS)

    Tanner, Ryan; Cecil, G. N.; Heitsch, F.

    2014-01-01

    Starbursts and AGN winds in galaxy cores can produce large scale outflows. Whether any given outburst can create an outflow depends on several variables including the rate at which the energy is injected into the interstellar medium (ISM), the distribution of clouds with in the ISM, and the overall shape of the ISM. Previous simulations by Cooper et al. (2008) reproduce linear filaments like that in M 82, but were limited in the parameter space that they could explore. We have modified the public Athena hydro code (Stone et al. 2008) to greatly reduce the computation time of high resolution 3D simulations similar to Cooper et al. (2008) and to handle accurate gas cooling down to lower molecule-forming temperatures (10 K). We are exploring the parameter space of a galactic “blowout”, the origin and evolution of interesting ISM morphology such as the curved filamentary “towers” observed at the center of NGC 3079, and how different ISM morphologies may influence the outflow. These simulations are being compared with spectral imaging obtained with the Herschel space telescope to study the connection between regions of the cold neutral medium, warm neutral medium, and warm ionized medium. Those observations are being presented in another session of this AAS meeting. Our work is supported by NASA/Herschel and NC Space Grant funding.

  12. Structural Study of the RIPoptosome Core Reveals a Helical Assembly for Kinase Recruitment

    PubMed Central

    2015-01-01

    Receptor interaction protein kinase 1 (RIP1) is a molecular cell-fate switch. RIP1, together with Fas-associated protein with death domain (FADD) and caspase-8, forms the RIPoptosome that activates apoptosis. RIP1 also associates with RIP3 to form the necrosome that triggers necroptosis. The RIPoptosome assembles through interactions between the death domains (DDs) of RIP1 and FADD and between death effector domains (DEDs) of FADD and caspase-8. In this study, we analyzed the overall structure of the RIP1 DD/FADD DD complex, the core of the RIPoptosome, by negative-stain electron microscopy and modeling. The results show that RIP1 DD and FADD DD form a stable complex in vitro similar to the previously described Fas DD/FADD DD complex, suggesting that the RIPoptosome and the Fas death-inducing signaling complex share a common assembly mechanism. Both complexes adopt a helical conformation that requires type I, II, and III interactions between the death domains. PMID:25119434

  13. Composite Cores

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Spang & Company's new configuration of converter transformer cores is a composite of gapped and ungapped cores assembled together in concentric relationship. The net effect of the composite design is to combine the protection from saturation offered by the gapped core with the lower magnetizing requirement of the ungapped core. The uncut core functions under normal operating conditions and the cut core takes over during abnormal operation to prevent power surges and their potentially destructive effect on transistors. Principal customers are aerospace and defense manufacturers. Cores also have applicability in commercial products where precise power regulation is required, as in the power supplies for large mainframe computers.

  14. NON-EQUILIBRIUM CHEMISTRY OF DYNAMICALLY EVOLVING PRESTELLAR CORES. I. BASIC MAGNETIC AND NON-MAGNETIC MODELS AND PARAMETER STUDIES

    SciTech Connect

    Tassis, Konstantinos; Willacy, Karen; Yorke, Harold W.; Turner, Neal J.

    2012-07-01

    We combine dynamical and non-equilibrium chemical modeling of evolving prestellar molecular cloud cores and investigate the evolution of molecular abundances in the contracting core. We model both magnetic cores, with varying degrees of initial magnetic support, and non-magnetic cores, with varying collapse delay times. We explore, through a parameter study, the competing effects of various model parameters in the evolving molecular abundances, including the elemental C/O ratio, the temperature, and the cosmic-ray ionization rate. We find that different models show their largest quantitative differences at the center of the core, whereas the outer layers, which evolve slower, have abundances which are severely degenerate among different dynamical models. There is a large range of possible abundance values for different models at a fixed evolutionary stage (central density), which demonstrates the large potential of chemical differentiation in prestellar cores. However, degeneracies among different models, compounded with uncertainties induced by other model parameters, make it difficult to discriminate among dynamical models. To address these difficulties, we identify abundance ratios between particular molecules, the measurement of which would have maximal potential for discrimination among the different models examined here. In particular, we find that the ratios between NH{sub 3} and CO, NH{sub 2} and CO, and NH{sub 3} and HCO{sup +} are sensitive to the evolutionary timescale, and that the ratio between HCN and OH is sensitive to the C/O ratio. Finally, we demonstrate that measurements of the central deviation (central depletion or enhancement) of abundances of certain molecules are good indicators of the dynamics of the core.

  15. Deep Chandra study of the truncated cool core of the Ophiuchus cluster

    NASA Astrophysics Data System (ADS)

    Werner, N.; Zhuravleva, I.; Canning, R. E. A.; Allen, S. W.; King, A. L.; Sanders, J. S.; Simionescu, A.; Taylor, G. B.; Morris, R. G.; Fabian, A. C.

    2016-08-01

    We present the results of a deep Chandra observation of the Ophiuchus cluster, the second brightest galaxy cluster in the X-ray sky. The cluster hosts a truncated cool core, with a temperature increasing from kT ˜ 1 keV in the core to kT ˜ 9 keV at r ˜ 30 kpc. Beyond r ˜ 30 kpc, the intracluster medium (ICM) appears remarkably isothermal. The core is dynamically disturbed with multiple sloshing-induced cold fronts, with indications for both Rayleigh-Taylor and Kelvin-Helmholtz instabilities. The residual image reveals a likely subcluster south of the core at the projected distance of r ˜ 280 kpc. The cluster also harbours a likely radio phoenix, a source revived by adiabatic compression by gas motions in the ICM. Even though the Ophiuchus cluster is strongly dynamically active, the amplitude of density fluctuations outside of the cooling core is low, indicating velocities smaller than ˜100 km s-1. The density fluctuations might be damped by thermal conduction in the hot and remarkably isothermal ICM, resulting in our underestimate of gas velocities. We find a surprising, sharp surface brightness discontinuity, that is curved away from the core, at r ˜ 120 kpc to the south-east of the cluster centre. We conclude that this feature is most likely due to gas dynamics associated with a merger. The cooling core lacks any observable X-ray cavities and the active galactic nucleus (AGN) only displays weak, point-like radio emission, lacking lobes or jets. The lack of strong AGN activity may be due to the bulk of the cooling taking place offset from the central supermassive black hole.

  16. Natural abundance carbon-13 nuclear magnetic resonance studies of histone and DNA dynamics in nucleosome cores.

    PubMed

    Hilliard, P R; Smith, R M; Rill, R L

    1986-05-01

    Natural abundance carbon-13 nuclear magnetic resonance spectra (67.9 MHz) were obtained for native nucleosome cores: cores dissociated in 2 M NaCl and 2 M NaCl, 6 M urea; and cores degraded with DNase I plus proteinase K. Phosphorus-31 NMR spectra of native and dissociated cores and core length DNA were also obtained at 60.7 MHz. The 31P resonance and spin-lattice relaxation time (T1) of DNA were only slightly affected by packaging in nucleosome cores, in agreement with other reports, but 13C resonances of DNA were essentially unobservable. The loss of DNA spectral intensity suggests that rapid internal motions of DNA sugar carbons in protein-free DNA previously demonstrated by 13C NMR methods are partly restricted in nucleosomes. The 13C spectrum of native cores contains many narrow intense resonances assigned to lysine side chain and alpha-carbons, glycine alpha-carbons, alanine alpha- and beta- carbons, and arginine side chain carbons. Several weaker resonances were also assigned. The narrow line widths, short T1 values, and non-minimal nuclear Overhauser enhancements of these resonances, including alpha- and beta-carbons, show that some terminal chain segments of histones in nucleosomes are as mobile as small random coil polypeptides. The mobile segments include about 9% of all histone residues and 25% of all lysines, but only 10% of all arginines. The compositions of these segments indicate that mobile regions are located in amino- or carboxyl-terminal sequences of two or more histones. In addition, high mobility was observed for side chain carbons of 45-50% of all lysines (delta and epsilon carbons) and about 25% of all arginines (zeta carbon) in histones (including those in mobile segments), suggesting that basic residues in terminal histone sequences are not strongly involved in nucleosome structure and may instead help stabilize higher order chromatin structure. PMID:3700380

  17. Evaluation of shear bond strength between zirconia core and ceramic veneers fabricated by pressing and layering techniques: In vitro study

    PubMed Central

    Subash, M.; Vijitha, D.; Deb, Saikat; Satish, A.; Mahendirakumar, N.

    2015-01-01

    Statement of Problem: Although ceramic veneered on to zirconia core have been in use for quite some time, information regarding the comparative evaluation of the Shear bond strength of Pressable & Layered ceramic veneered on to zirconia core is limited. Purpose of study: To evaluate the shear bond strength of zirconia core and ceramic veneer fabricated by two different techniques, Layering (Noritake CZR) and Pressing (Noritake, CZR Press). Materials and Method: 20 samples of zirconia blocks were fabricated and the samples were divided into group A & B. Group A - Ceramic Veneered over zirconia core by pressing using Noritake CZR Press. Group B - Ceramic Veneered over zirconia core by layering using Noritake CZR. The veneered specimens were mounted on to the center of a PVC tube using self-cure acrylic resin leaving 3 mm of the veneered surface exposed as cantilever. Using a Universal testing machine the blocks were loaded up to failure. Result: The results were tabulated by using independent samples t-test. The mean shear bond strength for Pressed specimens was 12.458 ± 1.63(S.D) MPa and for layered specimens was 8.458 ± 0.845(S.D) MPa. Conclusion: Pressed specimens performed significantly better than the layered specimen with a P value 0.001. Clinicians and dental laboratory technicians should consider the use of pressed ceramics as an alternative to traditional layering procedures to reduce the chances of chipping or de-lamination of ceramics PMID:26538929

  18. Study on core radius minimization for long life Pb-Bi cooled CANDLE burnup scheme based fast reactor

    NASA Astrophysics Data System (ADS)

    Afifah, Maryam; Miura, Ryosuke; Su'ud, Zaki; Takaki, Naoyuki; Sekimoto, H.

    2015-09-01

    Fast Breeder Reactor had been interested to be developed over the world because it inexhaustible source energy, one of those is CANDLE reactor which is have strategy in burn-up scheme, need not control roads for control burn-up, have a constant core characteristics during energy production and don't need fuel shuffling. The calculation was made by basic reactor analysis which use Sodium coolant geometry core parameter as a reference core to study on minimum core reactor radius of CANDLE for long life Pb-Bi cooled, also want to perform pure coolant effect comparison between LBE and sodium in a same geometry design. The result show that the minimum core radius of Lead Bismuth cooled CANDLE is 100 cm and 500 MWth thermal output. Lead-Bismuth coolant for CANDLE reactor enable to reduce much reactor size and have a better void coefficient than Sodium cooled as the most coolant for FBR, then we will have a good point in safety analysis.

  19. Development of a new academic digital library: a study of usage data of a core medical electronic journal collection

    PubMed Central

    Shearer, Barbara S.; Klatt, Carolyn; Nagy, Suzanne P.

    2009-01-01

    Objectives: The current study evaluates the results of a previously reported method for creating a core medical electronic journal collection for a new medical school library, validates the core collection created specifically to meet the needs of the new school, and identifies strategies for making cost-effective e-journal selection decisions. Methods: Usage data were extracted for four e-journal packages (Blackwell-Synergy, Cell Press, Lippincott Williams & Wilkins, and ScienceDirect). Usage was correlated with weighted point values assigned to a core list of journal titles, and each package was evaluated for relevancy and cost-effectiveness to the Florida State University College of Medicine (FSU COM) population. Results: The results indicated that the development of the core list was a valid method for creating a new twenty-first century, community-based medical school library. Thirty-seven journals are identified for addition to the FSU COM core list based on use by the COM, and areas of overlapping research interests between the university and the COM are identified based on use of specific journals by each population. Conclusions: The collection development approach that evolved at the FSU COM library was useful during the initial stages of identifying and evaluating journal selections and in assessing the relative value of a particular journal package for the FSU COM after the school was established. PMID:19404499

  20. Study on core radius minimization for long life Pb-Bi cooled CANDLE burnup scheme based fast reactor

    SciTech Connect

    Afifah, Maryam Su’ud, Zaki; Miura, Ryosuke; Takaki, Naoyuki; Sekimoto, H.

    2015-09-30

    Fast Breeder Reactor had been interested to be developed over the world because it inexhaustible source energy, one of those is CANDLE reactor which is have strategy in burn-up scheme, need not control roads for control burn-up, have a constant core characteristics during energy production and don’t need fuel shuffling. The calculation was made by basic reactor analysis which use Sodium coolant geometry core parameter as a reference core to study on minimum core reactor radius of CANDLE for long life Pb-Bi cooled, also want to perform pure coolant effect comparison between LBE and sodium in a same geometry design. The result show that the minimum core radius of Lead Bismuth cooled CANDLE is 100 cm and 500 MWth thermal output. Lead-Bismuth coolant for CANDLE reactor enable to reduce much reactor size and have a better void coefficient than Sodium cooled as the most coolant for FBR, then we will have a good point in safety analysis.

  1. Structural and electronic properties of CdS/ZnS core/shell nanowires: A first-principles study

    NASA Astrophysics Data System (ADS)

    Kim, Hyo Seok; Kim, Yong-Hoon

    2015-03-01

    Carrying out density functional theory (DFT) calculation, we studied the relative effects of quantum confinement and strain on the electronic structures of II-IV semiconductor compounds with a large lattice-mismatch, CdS and ZnS, in the core/shell nanowire geometry. We considered different core radii and shell thickness of the CdS/ZnS core/shell nanowire, different surface facets, and various defects in the core/shell interface and surface regions. To properly describe the band level alignment at the core/shell boundary, we adopted the self-interaction correction (SIC)-DFT scheme. Implications of our findings in the context of device applications will be also discussed. This work was supported by the Basic Science Research Grant (No. 2012R1A1A2044793), Global Frontier Program (No. 2013-073298), and Nano-Material Technology Development Program (2012M3A7B4049888) of the National Research Foundation funded by the Ministry of Education, Science and Technology of Korea. Corresponding author

  2. A finite element study of teeth restored with post and core: Effect of design, material, and ferrule

    PubMed Central

    Upadhyaya, Viram; Bhargava, Akshay; Parkash, Hari; Chittaranjan, B.; Kumar, Vivek

    2016-01-01

    Background: Different postdesigns and materials are available; however, no consensus exists regarding superiority for stress distribution. The aim of this study was to evaluate the effect of design and material of post with or without ferrule on stress distribution using finite element analysis. Materials and Methods: A total of 12 three-dimensional (3D) axisymmetric models of postretained central incisors were made: Six with ferrule design and six without it. Three of these six models had tapered posts, and three had parallel posts. The materials tested were titanium post with a composite resin core, nickel chromium cast post and core, and fiber reinforced composite (FRC) post with a composite resin core. The stress analysis was done using ANSYS software. The load of 100 N at an angle of 45΀ was applied 2 mm cervical to incisal edge on the palatal surface and results were analyzed using 3D von Mises criteria. Results: The highest amount of stress was in the cervical region. Overall, the stress in the tapered postsystem was more than the parallel one. FRC post and composite resin core recorded minimal stresses within the post but the stresses transmitted to cervical dentin were more as compared to other systems. Minimal stresses in cervical dentine were observed where the remaining coronal dentin was strengthen by ferrule. Conclusion: A rigid material with high modulus of elasticity for post and core system creates most uniform stress distribution pattern. Ferrule provides uniform distribution of stresses and decreases the cervical stresses. PMID:27274343

  3. Image guided versus palpation guided core needle biopsy of palpable breast masses: a prospective study

    PubMed Central

    Hari, Smriti; Kumari, Swati; Srivastava, Anurag; Thulkar, Sanjay; Mathur, Sandeep; Veedu, Prasad Thotton

    2016-01-01

    Background & objectives: Biopsy of palpable breast masses can be performed manually by palpation guidance or under imaging guidance. Based on retrospective studies, image guided biopsy is considered more accurate than palpation guided breast biopsy; however, these techniques have not been compared prospectively. We conducted this prospective study to verify the superiority and determine the size of beneficial effect of image guided biopsy over palpation guided biopsy. Methods: Over a period of 18 months, 36 patients each with palpable breast masses were randomized into palpation guided and image guided breast biopsy arms. Ultrasound was used for image guidance in 33 patients and mammographic (stereotactic) guidance in three patients. All biopsies were performed using 14 gauge automated core biopsy needles. Inconclusive, suspicious or imaging-histologic discordant biopsies were repeated. Results: Malignancy was found in 30 of 36 women in palpation guided biopsy arm and 27 of 36 women in image guided biopsy arm. Palpation guided biopsy had sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 46.7, 100, 100, 27.3 per cent, respectively, for diagnosing breast cancer. Nineteen of 36 women (52.8%) required repeat biopsy because of inadequate samples (7 of 19), suspicious findings (2 of 19) or imaging-histologic discordance (10 of 19). On repeat biopsy, malignancy was found in all cases of imaging-histologic discordance. Image guided biopsy had 96.3 per cent sensitivity and 100 per cent specificity. There was no case of inadequate sample or imaging-histologic discordance with image guided biopsy. Interpretation & conclusions: Our results showed that in palpable breast masses, image guided biopsy was superior to palpation guided biopsy in terms of sensitivity, false negative rate and repeat biopsy rates. PMID:27488003

  4. Core to Atmosphere Exploration of Ice Giants: A Uranus Mission Concept Study

    NASA Astrophysics Data System (ADS)

    Jensema, R. J.; Arias-Young, T. M.; Wilkins, A. N.; Ermakov, A.; Bennett, C.; Dietrich, A.; Hemingway, D.; Klein, V.; Mane, P.; Marr, K. D.; Masterson, J.; Siegel, V.; Stober, K. J.; Talpe, M.; Vines, S. K.; Wetteland, C. J.

    2014-12-01

    Ice giants remain largely unexplored, as their large distance from the Sun limits both Earth-based observations and spacecraft visits. The significant occurrence of ice giant-sized planets among detected exoplanets presents an impetus to study Uranus to understand planetary formation, dynamics, and evolution. In addition, Uranus is also uniquely interesting, given the large inclination of its rotation axis and magnetospheric configuration. In this work, we design a mission concept that aims to maximize scientific return by measuring Uranus' chemical composition, internal structure, and magnetosphere, the first two being primary indicators of ice giant formation mechanisms. For this study, we analyze the trade space for a Uranus mission constrained by a cost cap of $1B. We discuss the decision making processes behind our choices of the science priorities, instrument suite and orbital configuration. Trade space decisions include a strong onboard instrument suite in lieu of a descent probe, an orbiter instead of a flyby mission, and design constraints on the power and propulsion systems. The mission, CAELUS (Core and Atmospheric Evolution Laboratory for Uranus Science), is designed for an August 2023 launch. Following a 14-year cruise with multiple planetary gravity assists, the spacecraft would begin its science mission, which consists of a series of ten 30-day near-polar orbits around Uranus. The instrument suite would consist of a microwave radiometer, Doppler seismometer, magnetometer, and UV spectrometer. These four instruments, along with a high-gain antenna capable of gravity science, would provide a comprehensive science return that meets the bulk of the scientific objectives of the 2013 NRC Planetary Science Decadal Survey for ice giants, most notably those regarding the chemical composition, interior structure, and dynamo of Uranus. This mission concept was created as part of an educational exercise for the 2014 Planetary Science Summer School at the Jet

  5. A Study on Factors Influencing Toughness of Basic Flux-Cored Weld of Modified 9Cr-1Mo Steel

    NASA Astrophysics Data System (ADS)

    Arivazhagan, B.; Kamaraj, M.

    2011-10-01

    Flux-cored arc welding (FCAW) is relatively a new process for joining of modified 9Cr-1Mo (P91) steel. In this study, effect of shielding gas composition, inclusion content, gas tungsten-arc welding (GTAW) surface remelting, and postweld heat treatment (PWHT) on toughness were investigated. The high amount of silicon resulted in the formation of δ-ferrite in basic flux-cored weld. A mixture of 80% argon + 20% (80A) carbon dioxide shielding gas during welding resulted in the required toughness of 47 J at room temperature. The 95% argon + 5% carbon dioxide (95A) gas-shielded welds have lower toughness due to higher amount of δ-ferrite (4%) than 80% argon + 20% carbon dioxide welds (2%). In essence, most desirable shielding gas medium to achieve optimum toughness was 80% argon + 20% carbon dioxide in basic flux-cored arc welding.

  6. ELECTROCHEMICAL CORROSION STUDIES FOR TANK 241-AN-107 CORE 309 SEGMENTS 21R1 & 21R2

    SciTech Connect

    DUNCAN JB

    2007-11-13

    Liquid waste in tank 241-AN-107 is below Technical Safety Requirements Administrative Control 5.16 (AC 5.16) limits. Electrochemical corrosion testing was performed on Core 309, Segments 21R1 and 21R2, to provide information on the conductivity and corrosive tendencies of the tank saltcake and interstitial liquid. This report describes data obtained under the execution of RPP-PLAN-29001, 'Electrochemical Corrosion Studies for Tank 241-AN-107 Core 309, Segments 21R1 and 21R2'. Analytical results are presented that show supernatant was within the limits while the interstitial liquid remained below the limits for the analytical cores. Applicable AC 5.16 chemistry control limits for AN-107 are presented.

  7. Synthesis and characterization of core-shell acrylate based latex and study of its reactive blends.

    PubMed

    Liu, Xiang; Fan, Xiao-Dong; Tang, Min-Feng; Nie, Ying

    2008-03-01

    Techniques in resin blending are simple and efficient method for improving the properties of polymers, and have been used widely in polymer modification field. However, polymer latex blends such as the combination of latexes, especially the latexes with water-soluble polymers, were rarely reported. Here, we report a core-shell composite latex synthesized using methyl methacrylate (MMA), butyl acrylate (BA), 2-ethylhexyl acrylate (EHA) and glycidyl methacrylate (GMA) as monomers and ammonium persulfate and sodium bisulfite redox system as the initiator. Two stages seeded semi-continuous emulsion polymerization were employed for constructing a core-shell structure with P(MMA-co-BA) component as the core and P(EHA-co-GMA) component as the shell. Results of Transmission Electron Microscopy (TEM) and Dynamics Light Scattering (DLS) tests confirmed that the particles obtained are indeed possessing a desired core-shell structural character. Stable reactive latex blends were prepared by adding the latex with waterborne melamine-formaldehyde resin (MF) or urea-formaldehyde resin (UF). It was found that the glass transition temperature, the mechanical strength and the hygroscopic property of films cast from the latex blends present marked enhancements under higher thermal treatment temperature. It was revealed that the physical properties of chemically reactive latexes with core-shell structure could be altered via the change of crosslinking density both from the addition of crosslinkers and the thermal treatment. PMID:19325753

  8. Synthesis and Characterization of Core-Shell Acrylate Based Latex and Study of Its Reactive Blends

    PubMed Central

    Liu, Xiang; Fan, Xiao-Dong; Tang, Min-Feng; Nie, Ying

    2008-01-01

    Techniques in resin blending are simple and efficient method for improving the properties of polymers, and have been used widely in polymer modification field. However, polymer latex blends such as the combination of latexes, especially the latexes with water-soluble polymers, were rarely reported. Here, we report a core-shell composite latex synthesized using methyl methacrylate (MMA), butyl acrylate (BA), 2-ethylhexyl acrylate (EHA) and glycidyl methacrylate (GMA) as monomers and ammonium persulfate and sodium bisulfite redox system as the initiator. Two stages seeded semi-continuous emulsion polymerization were employed for constructing a core-shell structure with P(MMA-co-BA) component as the core and P(EHA-co-GMA) component as the shell. Results of Transmission Electron Microscopy (TEM) and Dynamics Light Scattering (DLS) tests confirmed that the particles obtained are indeed possessing a desired core-shell structural character. Stable reactive latex blends were prepared by adding the latex with waterborne melamine-formaldehyde resin (MF) or urea-formaldehyde resin (UF). It was found that the glass transition temperature, the mechanical strength and the hygroscopic property of films cast from the latex blends present marked enhancements under higher thermal treatment temperature. It was revealed that the physical properties of chemically reactive latexes with core-shell structure could be altered via the change of crosslinking density both from the addition of crosslinkers and the thermal treatment. PMID:19325753

  9. Models of molecular cloud cores. II. Multitransition study of CS-34

    SciTech Connect

    Mundy, L.G.; Evans, N.J.,II; Snell, R.L.; Goldsmith, P.F.; Bally, J.

    1986-07-01

    The dense cores embedded in the M17, S140 and NGC 2024 molecular clouds are mapped in the J = 5-4, J = 3-2, and J = 2-1 transitions of CS-34, and these lines are found to be a factor of 3-4 weaker, and 25 percent narrower, than the CS lines mapped in these cores by Snell et al. (1984). The data are well fitted by spherical LGV models for the excitation, and the excellent correlation between the CS-34 and CS column densities corroborates the absence of a systematic increase in the gas density with decreasing core radius found by Snell et al. Though the CS/CS-34 column density ratio is 9-17, rather than the terrestrial value of 22.5, the column density relationship is linear. The data support of a clump model in which the column density distribution in the core is determined by the volume filling factor of clumps with high, fairly uniform gas density, and it is suggested that the dense gas in the data represents the dominant component of the core gas. 22 references.

  10. Common Core State Standards for English Language Arts & Literacy in History/Social Studies, Science, and Technical Subjects

    ERIC Educational Resources Information Center

    Common Core State Standards Initiative, 2010

    2010-01-01

    The Common Core State Standards for English Language Arts & Literacy in History/Social Studies, Science, and Technical Subjects ("the Standards") are the culmination of an extended, broad-based effort to fulfill the charge issued by the states to create the next generation of K-12 standards in order to help ensure that all students are college and…

  11. Transitioning to the Common Core State Standards for Mathematics: A Mixed Methods Study of Elementary Teachers' Experiences and Perspectives

    ERIC Educational Resources Information Center

    Swars, Susan Lee; Chestnutt, Cliff

    2016-01-01

    This mixed methods study explored elementary teachers' (n = 73) experiences with and perspectives on the recently implemented Common Core State Standards for Mathematics (CCSS-Mathematics) at a high-needs, urban school. Analysis of the survey, questionnaire, and interview data reveals the findings cluster around: familiarity with and preparation…

  12. The Common Core State Standards: An Opportunity to Enhance Formative Assessment in History/Social Studies Classrooms

    ERIC Educational Resources Information Center

    Ateh, Comfort M.; Wyngowski, Aaron J.

    2015-01-01

    This article discusses the opportunity that the Common Core State Standards (CCSS) present for enhancing formative assessment (FA) in history and social studies classrooms. There is evidence that FA can enhance learning for students if implemented well. Unfortunately, teachers continue to be challenged in implementing FA in their classrooms. We…

  13. Professional Development for Promoting 21st Century Skills and Common Core State Standards in Foreign Language and Social Studies Classrooms

    ERIC Educational Resources Information Center

    Beriswill, Joanne Elizabeth; Bracey, Pamela Scott; Sherman-Morris, Kathleen; Huang, Kun; Lee, Sang Joon

    2016-01-01

    To help satisfy the pressing need for technology-related professional development for in-service teachers, the Global Academic Essentials Teacher Institute (GAETI) was implemented to provide in-service foreign language and social studies teachers with content, pedagogy, and technology explorations centered on the teaching of the Common Core State…

  14. Design Study for a Low-Enriched Uranium Core for the High Flux Isotope Reactor, Annual Report for FY 2006

    SciTech Connect

    Primm, R. T.; Ellis, R. J.; Gehin, J. C.; Clarno, K. T.; Williams, K. A.; Moses, D. L.

    2006-11-01

    Neutronics and thermal-hydraulics studies show that, for equivalent operating power [85 MW(t)], a low-enriched uranium (LEU) fuel cycle based on uranium-10 wt % molybdenum (U-10Mo) metal foil with radially, “continuously graded” fuel meat thickness results in a 15% reduction in peak thermal flux in the beryllium reflector of the High Flux Isotope Reactor (HFIR) as compared to the current highly enriched uranium (HEU) cycle. The uranium-235 content of the LEU core is almost twice the amount of the HEU core when the length of the fuel cycle is kept the same for both fuels. Because the uranium-238 content of an LEU core is a factor of 4 greater than the uranium-235 content, the LEU HFIR core would weigh 30% more than the HEU core. A minimum U-10Mo foil thickness of 84 μm is required to compensate for power peaking in the LEU core although this value could be increased significantly without much penalty. The maximum U-10Mo foil thickness is 457μm. Annual plutonium production from fueling the HFIR with LEU is predicted to be 2 kg. For dispersion fuels, the operating power for HFIR would be reduced considerably below 85 MW due to thermal considerations and due to the requirement of a 26-d fuel cycle. If an acceptable fuel can be developed, it is estimated that $140 M would be required to implement the conversion of the HFIR site at Oak Ridge National Laboratory from an HEU fuel cycle to an LEU fuel cycle. To complete the conversion by fiscal year 2014 would require that all fuel development and qualification be completed by the end of fiscal year 2009. Technological development areas that could increase the operating power of HFIR are identified as areas for study in the future.

  15. Computational Study on the Steady-state Impedance of Saturated-core Superconducting Fault Current Limiter

    NASA Astrophysics Data System (ADS)

    Zhang, C.; Tang, Y.; Liang, S.; Ren, L.; Wang, Z.; Xu, Y.

    This paper presents the electromagnetic analysis of a high voltage saturated-core superconducting fault current limiter (SCSFCL). The numerical analyses of a three-dimensional (3D) model is shown, and the specific parameters are given. The model focus on the steady-state impedance of the limiter when connected to the power grid. It analyzed the dependence of steady-state impedance on the AC coil current, and the relationship between oil gap and coil inductance. The results suggest that, adding oil gap between slice of silicon steel can reduce the core cross-section, restrain the ultraharmonic and decrease the steady-state impedance. As the core cross-section of AC limb decreased from 4344 cm2 to 3983 cm2, the total harmonic distortion for voltage decreased from 2.4% to 1.8%, and the impedance decreased from 1.082 Ω to 1.069 Ω(Idc=400A,Iac=1296A).

  16. Particle-core study of halo dynamics in periodic-focusing channels

    SciTech Connect

    Wang, Tai-Sen F.

    2000-01-01

    This paper reports on an approach to investigate the dynamics of halo particles in mismatched charged-particle beams propagating through periodic-focusing channels using the particle-core model. The proposed method employs canonical transformations to minimize, in new phase-space variables, the flutter due to the periodic focusing to allow making stroboscopic plots. Applying this method, we find that in periodic-focusing systems, certain particles initially not in the halo region can be brought into resonance with the core oscillation to become halo particles. (c) 2000 The American Physical Society.

  17. Potassium-induced charge redistribution on Si(111) surfaces studied by core-level photoemission spectroscopy

    SciTech Connect

    Ma, Y. ); Chen, C.T.; Meigs, G.; Sette, F. ); Illing, G. ); Shigakawa, H. )

    1992-03-15

    High-resolution core-level photoemission spectra of the K/Si(111)(7{times}7) surface system are presented. The Si 2{ital p} results show that potassium adsorption induces a Si 2{ital p} core level to shift to o/Ihighero/P binding energy, i.e., to the opposite direction than that expected from the Si-K electronegativity differences. This result is compared with that of the K/Si(111)({radical}3 {times} {radical}3 ){ital R}30{degree}-B system and is interpreted in terms of the K-induced charge redistribution between the Si-adatom--rest-atom pair.

  18. Collecting core data in severely injured patients using a consensus trauma template: an international multicentre study

    PubMed Central

    2011-01-01

    Introduction No worldwide, standardised definitions exist for documenting, reporting and comparing data from severely injured trauma patients. This study evaluated the feasibility of collecting the data variables of the international consensus-derived Utstein Trauma Template. Methods Trauma centres from three different continents were invited to submit Utstein Trauma Template core data during a defined period, for up to 50 consecutive trauma patients. Directly admitted patients with a New Injury Severity Score (NISS) equal to or above 16 were included. Main outcome variables were data completeness, data differences and data collection difficulty. Results Centres from Europe (n = 20), North America (n = 3) and Australia (n = 1) submitted data on 965 patients, of whom 783 were included. Median age was 41 years (interquartile range (IQR) 24 to 60), and 73.1% were male. Median NISS was 27 (IQR 20 to 38), and blunt trauma predominated (91.1%). Of the 36 Utstein variables, 13 (36%) were collected by all participating centres. Eleven (46%) centres applied definitions of the survival outcome variable that were different from those of the template. Seventeen (71%) centres used the recommended version of the Abbreviated Injury Scale (AIS). Three variables (age, gender and AIS) were documented in all patients. Completeness > 80% was achieved for 28 variables, and 20 variables were > 90% complete. Conclusions The Utstein Template was feasible across international trauma centres for the majority of its data variables, with the exception of certain physiological and time variables. Major differences were found in the definition of survival and in AIS coding. The current results give a clear indication of the attainability of information and may serve as a stepping-stone towards creation of a European trauma registry. PMID:21992236

  19. An experimental study of counter-rotating cores in elliptical galaxies

    NASA Technical Reports Server (NTRS)

    Miller, R. H.; Roelofs, G. R.; Smith, B. F.

    1990-01-01

    Recent observational studies (Franx and Illingworth 1987; Jedrzejewski and Schechter 1988; Bender 1988; Illingworth and Franx 1989) have shown that some elliptical galaxies have a small region near the center that rotates in the opposite direction from the outer parts of the galaxy. Often the rotation in the central part is much faster than that in the outer part. A few other galaxies show a small region near the center that rotates in the same direction as the rest of the galaxy, but much faster. Either way, the part near the center that shows a strange pattern of rotation (the 'core') has been interpreted as a distinct dynamical subsystem. Very briefly, the observational data seem to be that anomalies show up in rotation curves near the centers of some elliptical galaxies and that galaxies with these strange rotational properties do not show a photometric signature: there are no noticeable bumps in the brightness profile and no unusual shapes of isophotal contours that would suggest an excess of matter concentrated near the center. No strong color variations have been reported. The puzzle is to learn what we can about elliptical galaxies in general, and about galaxies with strange central regions in particular, from these observational facts. The authors' approach is experimental. They make a guess about the form of the dynamically distinct subsystem, and then build a galaxy model to test experimental consequences such as the amount of matter required to produce observable effects and the length of time over which these effects would remain observable. They sidestep questions about how the galaxy might have gotten to be that way in the first place. That gives them more freedom to explore a variety of suggestions about what kind of dynamical system might give rise to the observed rotational patterns.

  20. High-Pressure Studies on Iron Analogs with Application to Planetary Cores

    NASA Astrophysics Data System (ADS)

    Godwal, B. K.; Raju, S.; Geballe, Z.; Jeanloz, R.

    2013-12-01

    The properties of hexagonal close-packed (hcp) metals at high pressures are of geophysical interest because hcp Fe is likely to be the primary constituent of Earth's inner core. Zinc and cadmium crystallize in a distorted hcp structure, and undergo electronic topological transitions at high pressures manifested through anomalous values of the c/a crystal-axis ratio, compressibility and electron transport properties. There is renewed interest in such electronic transitions due to their recent association with anomalies in c/a, Debye velocity and Mössbauer center shift in Fe and Fe-Ni alloy near 40 GPa. Past high-pressure studies have shown that the c/a anomaly is larger in Cd as compared to Zn. Nonhydrostatic measurements on Cd reveal texture development, which is used in identifying deformation mechanisms in Os and Fe. Angular x-ray diffraction measurements in a resistively heated diamond-anvil cell, with argon as pressure medium, were carried out on Cd up to 25 GPa at room temperature. We minimized nonhydrostatic conditions by thermally annealing the sample at each pressure by heating it to 100° C, which resulted in sharpening of diffraction peaks. Variations of c/a with pressure revealed anomalies near 2, 7, 15 and 22 GPa, with corresponding anomalies in compression at similar pressures. We associate these anomalies with electronic topological transitions, based on results of first-principles electronic structure calculations at high pressures. Our data are in good agreement with independent measurements using helium as a pressure medium, so the anomalies cannot be ascribed to nonhydrostaticity. Also, in-situ x-ray powder-diffraction shows that the melting curve of Cd deviates from the Lindemann law above 1 GPa, consistent with the occurrence of electronic transitions.

  1. Secondary malignancies diagnosed using kidney needle core biopsies: a clinical and pathological study of 75 cases.

    PubMed

    Huang, He; Tamboli, Pheroze; Karam, Jose A; Vikram, Raghu; Zhang, Miao

    2016-06-01

    Involvement of the kidney by secondary malignancies is uncommon. Differentiating secondary malignancies from primary kidney/urothelial tumors can be challenging, especially on limited biopsy material. A retrospective search of our institutional archive from January 2002 to May 2015 identified 1572 cases of imaging-guided needle core biopsies of the kidney. Of these, 75 (5%) cases revealed a secondary malignancy; 48 (64%) patients had undergone the biopsy with a primary kidney tumor favored clinically. There were 39 male and 36 female patients with a mean age of 59.4 years (range, 21-83 years). The majority of the cases (n = 55, 73%) were metastases from solid tumors, with lung being the most common primary site (n = 22, 29%). Diffuse large B-cell lymphoma was the most common hematological malignancy (n = 6) secondarily involving the kidney. Radiographically, 58 (77%) cases presented as a solitary kidney mass. The primary malignancy was known prior to the kidney biopsy in 66 (88%) cases. The mean interval between diagnoses of the primary tumor and secondary involvement of the kidney was 4.5 years. Immunohistochemical stains were performed in 65 (87%) cases. Follow-up information was available for 73 patients; mean survival was 19.4 months, with 43 patients dead of their disease (mean, 12 months) and 30 patients alive at last follow-up (21 with and 9 without disease; mean, 30 months). Secondary malignancy in the kidney may clinically and pathologically mimic primary kidney tumors. Accurate diagnosis can be rendered by correlating pathological features with clinical and radiographic findings and judicious use of ancillary studies. PMID:26980018

  2. The USDA barley core collection: genetic diversity, population structure, and potential for genome-wide association studies.

    PubMed

    Muñoz-Amatriaín, María; Cuesta-Marcos, Alfonso; Endelman, Jeffrey B; Comadran, Jordi; Bonman, John M; Bockelman, Harold E; Chao, Shiaoman; Russell, Joanne; Waugh, Robbie; Hayes, Patrick M; Muehlbauer, Gary J

    2014-01-01

    New sources of genetic diversity must be incorporated into plant breeding programs if they are to continue increasing grain yield and quality, and tolerance to abiotic and biotic stresses. Germplasm collections provide a source of genetic and phenotypic diversity, but characterization of these resources is required to increase their utility for breeding programs. We used a barley SNP iSelect platform with 7,842 SNPs to genotype 2,417 barley accessions sampled from the USDA National Small Grains Collection of 33,176 accessions. Most of the accessions in this core collection are categorized as landraces or cultivars/breeding lines and were obtained from more than 100 countries. Both STRUCTURE and principal component analysis identified five major subpopulations within the core collection, mainly differentiated by geographical origin and spike row number (an inflorescence architecture trait). Different patterns of linkage disequilibrium (LD) were found across the barley genome and many regions of high LD contained traits involved in domestication and breeding selection. The genotype data were used to define 'mini-core' sets of accessions capturing the majority of the allelic diversity present in the core collection. These 'mini-core' sets can be used for evaluating traits that are difficult or expensive to score. Genome-wide association studies (GWAS) of 'hull cover', 'spike row number', and 'heading date' demonstrate the utility of the core collection for locating genetic factors determining important phenotypes. The GWAS results were referenced to a new barley consensus map containing 5,665 SNPs. Our results demonstrate that GWAS and high-density SNP genotyping are effective tools for plant breeders interested in accessing genetic diversity in large germplasm collections. PMID:24732668

  3. The Hollow Core: Failure of the General Education Curriculum. A Fifty College Study

    ERIC Educational Resources Information Center

    Latzer, Barry

    2004-01-01

    This report provides empirical proof of a disturbing trend in higher education. Over the last several decades colleges and universities have substituted so-called "distribution requirements" for a solid core curriculum. Distribution requirements enable students freely to choose their general education courses, the courses outside their…

  4. Common Core Implementation: Units of Study in Sacramento City. Practice Brief

    ERIC Educational Resources Information Center

    Knudson, Joel

    2014-01-01

    As district leaders search for the best ways to improve student learning with the Common Core State Standards, California districts are leading the way as early implementers of the new standards. The ideas and lessons emerging from their work can help other educators maximize the effectiveness of their own implementation efforts. This brief…

  5. The University of Utah's Integrated Core: A Case Study from a "Commuter Campus"

    ERIC Educational Resources Information Center

    Paisley, Karen; Spencer, Callie; Wells, Mary Sarah; Schwab, Keri

    2013-01-01

    This paper describes the Integrated Core (IC), the University of Utah's version of integrated curricula. We begin with a rationale for the IC, providing a background on the unique student demographics, and University-wide requirements that propelled our design. Our IC focuses specifically on active living, sustainability, and social justice…

  6. Synthetic Studies to Lyngbouilloside: A Phosphate Tether-Mediated Synthesis of the Macrolactone Core

    PubMed Central

    Chegondi, Rambabu

    2015-01-01

    A concise synthetic pathway to the originally assigned structure of lyngbouilloside macrolactone (3) is reported. The core macrocycle 3 was synthesized via a phosphate tether-mediated, one-pot, sequential RCM/CM/chemoselective hydrogenation reaction, Roskamp homologation, and a high yielding Boeckman acylketene cyclization. PMID:26388654

  7. Core muscle strengthening's improvement of balance performance in community-dwelling older adults: a pilot study.

    PubMed

    Kahle, Nicole; Tevald, Michael A

    2014-01-01

    To determine the effect of core muscle strengthening on balance in community-dwelling older adults, 24 healthy men and women between 65 and 85 years old were randomized to either exercise (EX; n = 12) or control (CON; n = 12) groups. The exercise group performed a core strengthening home exercise program thrice weekly for 6 wk. Core muscle (curl-up test), functional reach (FR) and Star Excursion Balance Test (SEBT) were assessed at baseline and follow-up. There were no group differences at baseline. At follow-up, EX exhibited significantly greater improvements in curl-up (Cohen's d = 4.4), FR (1.3), and SEBT (>1.9 for all directions) than CON. The change in curl-up was significantly correlated with the change in FR (r = .44, p = .03) and SEBT (r > .61, p ≤ .002). These results suggest that core strengthening should be part of a comprehensive balance-training program for older adults. PMID:23348043

  8. Study of Core Competency Elements and Factors Affecting Performance Efficiency of Government Teachers in Northeastern Thailand

    ERIC Educational Resources Information Center

    Chansirisira, Pacharawit

    2012-01-01

    The research aimed to investigate the core competency elements and the factors affecting the performance efficiency of the civil service teachers in the northeastern region, Thailand. The research procedure consisted of two steps. In the first step, the data were collected using a questionnaire with the reliability (Cronbach's Alpha) of 0.90. The…

  9. Environmental Education Teacher's Guide, Junior High School. A Core Experience Study of the Natural Environment.

    ERIC Educational Resources Information Center

    Bennett, Dean B.; Willink, Wesley H.

    This Environmental Education Teacher's Guide, developed for use in the junior high school, is designed to familiarize teachers with how an environmental education program can help in their teaching and in achieving the goals of the school. The suggested core activities in this guide are designed to be a motivating way of introducting junior high…

  10. Apps-olutely Perfect! Apps to Support Common Core in the History/Social Studies Classroom

    ERIC Educational Resources Information Center

    Waters, Stewart; Kenna, Joshua; Bruce, Darrian

    2016-01-01

    The inclusion of technology in the classroom is an increasingly important feature of effective instruction. The implementation of Common Core Standards in many states also requires teachers to consider new pedagogical strategies to support meaningful learning. This article explores the intersection between technology demands and curricular change…

  11. The Study on the Core Concepts of Contemporary Sociology of Education and Its Theoretical Construction

    ERIC Educational Resources Information Center

    Qian, Min-hui

    2006-01-01

    Within the sphere of contemporary social sciences, the terms "modernity," "post-modernity" and "globalization" have penetrated, as the core concepts, into various fields of social sciences in a logical way. In constituting the concept of "modernity," sociology of education develops the educational theory, as sociological theory does, into a "grand…

  12. Synthetic studies of callyspongiolide: synthesis of the macrolactone core of the molecule.

    PubMed

    Athe, Sudhakar; Sharma, Ashish; Marumudi, Kanakaraju; Ghosh, Subhash

    2016-07-12

    A concise synthetic strategy has been developed for the synthesis of the macrolactone core 2 of a unique polyketide callyspongiolide 1. The key features of the strategy included an Evan's asymmetric alkylation, diastereoselective Michael type alkylation, Brown's asymmetric allylation reaction, an allylic alkylation of an activated Z-allylic alcohol and an intramolecular Z-selective intramolecular H-W-E olefination. PMID:27337038

  13. Preservice Teacher Preparation for Common Core Standards and Assessments: A Pilot Study

    ERIC Educational Resources Information Center

    Pae, Holly; Freeman, Greta G.; Wash, Pamela D.

    2014-01-01

    Teacher preparation programs face great challenges in ensuring their graduates are prepared for the demands of today's classrooms. The authors explore how teacher accountability has evolved based upon federal legislation leading to adoption of the Common Core State Standards (CCSS). Recognizing that future teachers will be held accountable…

  14. Core outcome measures for exercise studies in people with multiple sclerosis: recommendations from a multidisciplinary consensus meeting.

    PubMed

    Paul, Lorna; Coote, Susan; Crosbie, Jean; Dixon, Diane; Hale, Leigh; Holloway, Ed; McCrone, Paul; Miller, Linda; Saxton, John; Sincock, Caroline; White, Lesley

    2014-10-01

    Evidence shows that exercise is beneficial for people with multiple sclerosis (MS); however, statistical pooling of data is difficult because of the diversity of outcome measures used. The objective of this review is to report the recommendations of an International Consensus Meeting for a core set of outcome measures for use in exercise studies in MS. From the 100 categories of the International Classification of Function Core Sets for MS, 57 categories were considered as likely/potentially likely to be affected by exercise and were clustered into seven core groups. Outcome measures to address each group were evaluated regarding, for example, psychometric properties. The following are recommended: Modified Fatigue Impact Scale (MFIS) or Fatigue Severity Scale (FSS) for energy and drive, 6-Minute Walk Test (6MWT) for exercise tolerance, Timed Up and Go (TUG) for muscle function and moving around, Multiple Sclerosis Impact Scale (MSIS-29) or Multiple Sclerosis Quality of Life-54 Instrument (MSQoL54) for quality of life and body mass index (BMI) or waist-hip ratio (WHR) for the health risks associated with excess body fat. A cost effectiveness analysis and qualitative evaluation should be included where possible. Using these core measures ensures that future meta-analyses of exercise studies in MS are more robust and thus more effectively inform practice. PMID:24639480

  15. GENIE: a software package for gene-gene interaction analysis in genetic association studies using multiple GPU or CPU cores

    PubMed Central

    2011-01-01

    Background Gene-gene interaction in genetic association studies is computationally intensive when a large number of SNPs are involved. Most of the latest Central Processing Units (CPUs) have multiple cores, whereas Graphics Processing Units (GPUs) also have hundreds of cores and have been recently used to implement faster scientific software. However, currently there are no genetic analysis software packages that allow users to fully utilize the computing power of these multi-core devices for genetic interaction analysis for binary traits. Findings Here we present a novel software package GENIE, which utilizes the power of multiple GPU or CPU processor cores to parallelize the interaction analysis. GENIE reads an entire genetic association study dataset into memory and partitions the dataset into fragments with non-overlapping sets of SNPs. For each fragment, GENIE analyzes: 1) the interaction of SNPs within it in parallel, and 2) the interaction between the SNPs of the current fragment and other fragments in parallel. We tested GENIE on a large-scale candidate gene study on high-density lipoprotein cholesterol. Using an NVIDIA Tesla C1060 graphics card, the GPU mode of GENIE achieves a speedup of 27 times over its single-core CPU mode run. Conclusions GENIE is open-source, economical, user-friendly, and scalable. Since the computing power and memory capacity of graphics cards are increasing rapidly while their cost is going down, we anticipate that GENIE will achieve greater speedups with faster GPU cards. Documentation, source code, and precompiled binaries can be downloaded from http://www.cceb.upenn.edu/~mli/software/GENIE/. PMID:21615923

  16. Core-core and core-valence correlation

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.

    1988-01-01

    The effect of (1s) core correlation on properties and energy separations was analyzed using full configuration-interaction (FCI) calculations. The Be 1 S - 1 P, the C 3 P - 5 S and CH+ 1 Sigma + or - 1 Pi separations, and CH+ spectroscopic constants, dipole moment and 1 Sigma + - 1 Pi transition dipole moment were studied. The results of the FCI calculations are compared to those obtained using approximate methods. In addition, the generation of atomic natural orbital (ANO) basis sets, as a method for contracting a primitive basis set for both valence and core correlation, is discussed. When both core-core and core-valence correlation are included in the calculation, no suitable truncated CI approach consistently reproduces the FCI, and contraction of the basis set is very difficult. If the (nearly constant) core-core correlation is eliminated, and only the core-valence correlation is included, CASSCF/MRCI approached reproduce the FCI results and basis set contraction is significantly easier.

  17. Compensation temperature in a dendrimer nano-system with a core-shell structure: Monte Carlo study

    NASA Astrophysics Data System (ADS)

    Belhaj, A.; Jabar, A.; Labrim, H.; Ziti, S.; Bahmad, L.; Laânab, L.; Benyoussef, A.

    2016-01-01

    In this work, we study the magnetic properties of a nanostructure based on an hexagonal core-shell geometry. The model is formed with core spins σ =3/2 and surface spins S=2. More precisely, we investigate the effect of the coupling exchange interactions in the absence/presence of both an external magnetic and crystal fields. In a first step, we elaborate the ground state phase diagrams, and then we discuss the stable phases. At different non null temperatures, we explore Monte Carlo to study computation and the magnetic properties. Among others, we find a compensation temperature between the spins σ and S. To close this study, we examine the hysteresis loop behaviors.

  18. [Nationwide questionnaire study in "the Model Core Curriculum" and current status for the undergraduate education in neurology].

    PubMed

    Sasaki, Hidenao; Arimura, Kimiyoshi; Itoyama, Yasuto; Kwak, Shin; Kira, Jun-Ichi; Nakashima, Kenji; Amano, Takahiro; Inoue, Kiyoharu; Uozumi, Takenori; Kohara, Nobuo; Tsuji, Sadatoshi; Tamagawa, Akira; Toyoshima, Itaru; Mizutani, Tomohiko; Yoshii, Fumihito; Sobue, Gen; Shimizu, Teruo

    2008-08-01

    To investigate the current state of education for undergraduates, the subcommittee of the Japanese Society of Neurology for undergraduate education sent a questionnaire on the 2001-version of Model Core Curriculum to the department of neurology in 80 medical universities and their 7 associate medical institutes throughout Japan. Answers were obtained from 56 out of those 87 institutes (64.4%). According to the answers, the Core Curriculum was introduced to the program of undergraduate education in 93% of those 56 universities. For the revision of neurology part in the current Core Curriculum, there are number of requests for improving the description on the neurological examination, list of common symptoms and disorders, and addition of therapeutics. Despite application of the Model Core Curriculum in medical education, the present study disclosed that there were considerable difference in the number and content of the lectures, and the duration of clinical clerkship in neurology ward. These differences of the curriculum and training program depends on not only the number of staffs, but also whether they are working as staffs in a department of neurology or as a small group of neurologists within a department other than neurology. PMID:18939474

  19. Systematic Studies of Shock Revival and the Subsequent Evolutions in Core-collapse Supernovae with Parametric Progenitor Models

    NASA Astrophysics Data System (ADS)

    Yamamoto, Yu; Yamada, Shoichi

    2016-02-01

    We conducted one-dimensional and two-dimensional hydrodynamic simulations of post-shock revival evolutions in core-collapse supernovae, employing the simple neutrino light bulb approximation to produce explosions rather easily. In order to estimate the explosion energy, we took into proper account nuclear recombinations and fusions consistently with the equation of state for matter not in statistical equilibrium in general. The methodology is similar to our previous work, but is somehow improved. In this paper, we studied the influence of the progenitor structure on the dynamics systematically. In order to expedite our understanding of the systematics, we constructed six parametric progenitor models, which are different in masses of Fe iron core and Si+S layer, instead of employing realistic models provided by stellar evolution calculations, which are sometimes of stochastic nature as a function of stellar mass on the main sequence. We found that the explosion energy is tightly correlated with the mass accretion rate at shock revival irrespective of dimension and the progenitors with light iron cores but with rather high entropies, which have yet to be produced by realistic stellar evolution calculations, may reproduce the canonical values of explosion energy and nickel mass. The mass of the Si+S layer is also important in the mass accretion history after bounce, on the other hand; the higher mass accretion rates and resultant heavier cores tend to hamper strong explosions.

  20. An Observational Study of the Molecular Cloud Core Toward IRAS 23133+6050

    NASA Astrophysics Data System (ADS)

    Wang, Min; Yang, Ji; Geng, Tao; Zhu, Liu-bin

    2008-01-01

    This paper reports 13CO, C 18O, HCO + (J = 1-0) spectral observations toward IRAS 23133+6050 with the 13.7 m millimeter-wave telescope at Qinghai Station of PMO. Corresponding to the 13CO, C 18O, HCO + line emissions, the size of the observed molecular cloud core is 4.0 pc, 2.1 pc and 2.3 pc, the virial mass is 2.7 × 10 3 M⊙, 0.9 × 10 3 M⊙ and 2.3 × 10 3 M⊙, and the volume density of H 2 is 2.7 × 10 3 cm -3, 5.1 × 10 3 cm -3 and 4.6 × 10 3 cm -3, respectively. Using the power-law function n( r) ˜ r- p, the spatial density distribution of the cloud core was analyzed, the obtained exponent p is respectively 1.75, 1.56 and 1.48 for the 13CO, C 18O and HCO + cores, and it is found that the density distribution becomes gradually flatter from the outer region to the inner region of the core. The HCO + abundance is 4.6 × 10 -10, one order of magnitude less than the value for dark clouds, and slightly less than that for giant molecular clouds. The 13CO/C 18O relative abundance ratio is 12.2, comparable with the value 11.8 for dark clouds, and the value 9.0 ˜ 15.6 for giant molecular clouds. A 13CO bipolar outflow is found in this region. The IRAS far-infrared luminosity and the virial masses give the luminosity-mass ratios 18.1, 51.1 and 21.2 from the three lines.

  1. Extensional fault cores in micritic carbonate - Case studies from the Gulf of Corinth, Greece

    NASA Astrophysics Data System (ADS)

    Bastesen, Eivind; Braathen, Alvar; Nøttveit, Henning; Gabrielsen, Roy H.; Skar, Tore

    2009-04-01

    The major Pisia and Doumena faults of the Corinth Rift, Greece, are both hosted by micritic carbonate rock. Their common fault elements are principal slip surfaces, layers of fault rocks, fault rock and host rock lenses, corrugations, and smaller shear and tension fractures. Along planar fault segments, a corrugated slip surface with an associated thin fault rock layer is formed. Well-developed down-dip corrugations indicate movement along the same surface over many fault increments. Bends/jogs in the faults are sites of complex structural relations, hosting frequent lenses, more porous fault rocks, and dense networks of fractures. Major jogs in the slip surfaces have both strike and dip-oriented undulating curvature that are associated with higher order fracture networks as well as frequent lenses. Fault core lens shapes of the Doumena fault show relationship of length vs. width of 3/2. Similarly, principal slip surfaces of the two faults show undulations with aspect ratios of amplitude vs. wavelength (1:19 and 1:14) in strike-direction, despite a prominent difference in down-dip geometry. The intrinsic deformation in fault cores of micritic carbonate supports a model in which fluids entered the core by damage zone fractures that are linked to the principal slip surface. Flow along the fault core was controlled by the fracture system of lenses, and thereby lens connectivity, but may have been hampered by flow-retarding fault rocks. The flow potential is especially well developed in fault bends and breached relays due to frequent lenses and well-developed fracture networks.

  2. A high-resolution study of complex organic molecules in hot cores

    NASA Astrophysics Data System (ADS)

    Calcutt, Hannah; Viti, Serena; Codella, Claudio; Beltrán, Maria T.; Fontani, Francesco; Woods, Paul M.

    2014-10-01

    We present the results of a line identification analysis using data from the IRAM Plateau de Bure Plateau de Bure Interferometer, focusing on six massive star-forming hot cores: G31.41+0.31, G29.96-0.02, G19.61-0.23, G10.62-0.38, G24.78+0.08A1 and G24.78+0.08A2. We identify several transitions of vibrationally excited methyl formate (HCOOCH3) for the first time in these objects as well as transitions of other complex molecules, including ethyl cyanide (C2H5CN), and isocyanic acid (HNCO). We also postulate a detection of one transition of glycolaldehyde (CH2(OH)CHO) in two new hot cores. We find G29.96-0.02, G19.61-0.23, G24.78+0.08A1 and G24.78+0.08A2 to be chemically very similar. G31.41+0.31, however, is chemically different: it manifests a larger chemical inventory and has significantly larger column densities. We suggest that it may represent a different evolutionary stage to the other hot cores in the sample, or it may surround a star with a higher mass. We derive column densities for methyl formate in G31.41+0.31, using the rotation diagram method, of 4 × 1017 cm-2 and a Trot of ˜170 K. For G29.96-0.02, G24.78+0.08A1 and G24.78+0.08A2, glycolaldehyde, methyl formate and methyl cyanide, all seem to trace the same material and peak at roughly the same position towards the dust emission peak. For G31.41+0.31, however, glycolaldehyde shows a different distribution to methyl formate and methyl cyanide and seems to trace the densest, most compact inner part of hot cores.

  3. An RXTE Study of M87 and the Core of the Virgo Cluster

    NASA Technical Reports Server (NTRS)

    Reynolds, Christopher S.; Heinz, Sebastian; Fabian, Andrew C.; Begelman, Mitchell C.

    1998-01-01

    We present hard X-ray observations of the nearby radio galaxy M87 and the core of the Virgo cluster using the Rossi X-ray Timing Explorer. These are the first hard X-ray observations of M87 not affected by contamination from the nearby Seyfert 2 galaxy NGC 4388. Thermal emission from Virgo's intracluster medium is clearly detected and has a spectrum indicative of kT approx. = 2.5 keV plasma with approximately 25% cosmic abundances. No non-thermal (power-law) emission from M87 is detected in the hard X-ray band, with fluctuations in the Cosmic X-ray Background being the limiting factor. Combining with ROSAT data, we infer that the X-ray spectrum of the M87 core and jet must be steep (Gamma(sub core) greater than 1.90 and Gamma(sub jet) greater than 1.75), and we discuss the implications of this result. In particular, these results are consistent with M87 being a mis-aligned BL-Lac object.

  4. An RXTE Study of M87 and the Core of the Virgo Cluster

    NASA Technical Reports Server (NTRS)

    Reynolds, Christopher S.; Heinz, Sebastian; Fabian, Andrew C.; Begelman, Mitchell C.

    1998-01-01

    We present hard X-ray observations of the nearby radio galaxy M87 and the core of the Virgo cluster using the Rossi X-ray 7Tming Explorer. These are the first hard X-ray observations of M87 not affected by contamination from the nearby Seyfert 2 galaxy NGC 4388. Thermal emission from Virgo's intracluster medium is clearly detected and has a spectrum indicative of kT is approximately equal to 2.5 keV plasma with approximately 25% cosmic abundances. No non-thermal (power-law) emission from M87 is detected in the hard X-ray band, with fluctuations in the Cosmic X-ray Background being the limiting factor. Combining with ROSAT data, we infer that the X-ray spectrum of the M87 core and jet must be steep (Gamma (sub core) > 1.90 and Gamma (sub jet) > 1.75), and we discuss the implications of this result. In particular, these results are consistent with M87 being a mis-aligned BL-Lac object.

  5. Studies of Deteriorated Heat Transfer in Prismatic Cores Stemming from Irradiation-Induced Geometry Distortion

    SciTech Connect

    Williams, Brian G.; Schultz, Richard R.; McEligot, Don M.; McCreery, Glenn

    2015-08-31

    A reference design for the Next Generation Nuclear Plant (NGNP) is to use General Atomics Modular High Temperature Gas-cooled Reactor (MHTGR). For such a configuration in normal operation, the helium coolant flow proceeds from the upper plenum to the lower plenum principally through the core coolant channels and the interstitial gaps (bypass flow) that separate the prismatic blocks from one another. Only the core prismatic blocks have coolant channels. The interstitial gaps are present throughout the core, the inner reflector region, and the out reflector region. The bypass flows in a prismatic gas-cooled reactor (GCR) are of potential concern because they reduce the desired flow rates in the coolant channels and, thereby, can increase outlet gas temperatures and maximum fuel temperatures. Consequently, it is appropriate to account for bypass flows in reactor thermal gas dynamic analyses. The objectives of this project include the following: fundamentally understand bypass flow and heat transfer at scaled, undistorted conditions and with geometry distortions; develop improved estimates of associated loss coefficients, surface friction and heat transfer for systems and network codes; and obtain related data for validation of CFD (computational fluid dynamic) or system (e.g., RELAP5) codes which can be employed in predictions for a GCR for normal power, reduced power, and residual heat removal operations.

  6. High resolution photoemission study of CdSe and CdSe/ZnS core-shell nanocrystals

    NASA Astrophysics Data System (ADS)

    Borchert, H.; Talapin, D. V.; McGinley, C.; Adam, S.; Lobo, A.; de Castro, A. R. B.; Möller, T.; Weller, H.

    2003-07-01

    Colloidally prepared CdSe and CdSe/ZnS core-shell nanocrystals passivated with trioctylphosphine/trioctylphosphine oxide and hexadecylamine have been studied by photoelectron spectroscopy with tuneable synchrotron radiation. High-resolution spectra of the Se 3d level in CdSe nanocrystals indicate the bonding of organic ligands not only to surface Cd but also to surface Se atoms. The investigation of the CdSe/ZnS core-shell nanocrystals allows us to determine the average thickness of the ZnS shell and to study the interface between the two semiconductor nanomaterials. The photoemission spectra indicate a rather well ordered interface. No evidence for interfacial bonds other than Cd-S and Se-Zn is found.

  7. Dark Filaments, Clouds and Cores: A Multiband IR Study of the Early Stages of Star Formation in Extended Structures

    NASA Astrophysics Data System (ADS)

    Smith, Howard

    Star formation typically begins in cold, dark clouds that are not spherically symmetric, but elongated as infrared dark clouds or long linear filaments. Their star-forming characteristics are thought to be sensitive to the geometries. We propose a systematic, detailed study of a sample of 168 of these dark clouds spanning a wide range of parameters using new archival data from Herschel and Spitzer. Archival Herschel photometry in particular enables for the first time a sensitive, systematic study of the full far-infrared continuum of these objects. We have distance determinations and ancillary molecule line measurements for all of our sources. Ten-band photometry (from 3.5um to 500um) will let us determine the luminosities, spectral energy distributions (SEDs), and estimate masses of these cold structures as functions of their star-formation activity. We will produce dust temperature and optical depth maps that will enable statistical studies of filaments and their cores; we expect statistics on over 500 protostellar cores. Our selected sources span a range of physical conditions: distances from 1 to 8 kpc, lengths from 0.1 to 80 pc, aspect ratios from below 2 to above 8, nominal core masses from about 1 to 500 Mo, and a range of geometries including linear, branching, hub-filament, and network configurations. We plan to use the extended Robitaille YSO models and SUNRISE radiative transfer models for prestellar cores to analyze a generic set of the most common objects, and then test their applicability across the sample. We will also bring other data to bear (WISE; 2MASS, millimeter) as is useful. We address three current, multi-faceted problems: (1) What are the density, temperature and optical depth structures of filaments and their cores? How do these parameters vary spatially for cores and the inter-core regions? How do these parameters correlate to filamentary or environmental properties? (2) What is the statistical distribution of these properties; in

  8. Release of quercetin from micellar nanoparticles with saturated and unsaturated core forming polyesters--a combined computational and experimental study.

    PubMed

    Hassanzadeh, Salman; Khoee, Sepideh; Beheshti, Abolghasem; Hakkarainen, Minna

    2015-01-01

    Computational and experimental studies were combined to obtain new insight into the widely reported anomalous release mechanism of hydrophobic drug (quercetin) from polymeric micellar nanoparticles. Saturated and unsaturated amphiphilic triblock copolymers from monomethoxy polyethylene glycol (mPEG), poly(butylene adipate) (PBA) and poly(cis-2-butene adipate) (PCBA) (mPEG-PBA-mPEG and mPEG-PCBA-mPEG) were utilized as model polymers to specify the contribution of polymer-micelle degradation and polymer-drug interactions on the observed differences in the release rates by applicable computational investigation and experimental evaluations. Monitoring the size of the micelles through the releasing process together with hydrolytic degradation studies of the core forming polymers proved that the contribution of polymer hydrolysis and micelle degradation on the observed differences in the release rates during the release time window was minimal. The compatibility between quercetin and the core forming polymer is another factor influencing the drug encapsulation and the relative release rate and it was therefore investigated theoretically (using density functional theory (DFT) at B3LYP/6-311(++)G level of theory) and experimentally (FT-IR imaging). The drug-polymer interactions in the core were shown to be much more important than the polymer and/or micelle swelling-dissociation-degradation processes under the studied conditions. PMID:25492006

  9. In situ high-pressure study of FeP: Implications for planetary cores

    NASA Astrophysics Data System (ADS)

    Gu, Tingting; Wu, Xiang; Qin, Shan; Dubrovinsky, Leonid

    2011-02-01

    FeP with MnP-type structure is isostructural with high-pressure FeS polymorphs (both post-troilite FeS and FeS VI), which are believed to exist in planetary cores. Due to similar PTX phase diagrams of binary Fe-P and Fe-S, phosphorus can incorporate with iron-sulfur at planetary core conditions. To understand such substitution and the high-pressure behavior of FeP, we investigate the structural stability of FeP up to 15.6 GPa and 1800 ± 200 K by combined in situ powder X-ray diffraction and Mössbauer spectroscopy. Our experimental results show that FeP remains the MnP-type structure throughout the PT range covered. Isothermal equation of state of FeP is obtained with V0 of 92.91(8) Å 3, B0 of 205(7) GPa, and B0 of 4. The shortest axis of the MnP-type FeP cell, the b-axis, is the most compressible, due to the soft edge-sharing octahedra along the b-axis. Mössbauer results show that no electronic structure changes occur up to 15.6 GPa, but indicate decreasing distortion of FeP 6 octahedron with pressure increasing. The behavior of FeP is quite different from that of FeS under high pressure and high temperature, suggesting that phosphorus will have a significant impact on stability and electronic properties of FeS within terrestrial planet cores.

  10. Steric and electronic contributions to the core reactivity of monoprotonated 5-phenylporphyrin: A DFT study

    NASA Astrophysics Data System (ADS)

    Presselt, Martin; Wojdyr, Michal; Beenken, Wichard J. D.; Kruk, Mikalai; Martínez, Todd J.

    2014-05-01

    We analyse the behaviour of mono-protonated 5-phenylporphyrin upon por-ph torsion to get insights into torsion-induced reactivity changes. In contrast to the majority of structures, nitrogen-accessibility volume (Vreact) is larger for front-side (exposed nitrogen) than for backside-attacks at the optimised structure. The high reactivity of nitrogen is determined by the electrostatic potential distribution inside the porphyrine core. Even if Vreact at certain structures is smaller for front side than for backside attacks the mean electrostatic-potential-density φ inside Vreact reveals a lower barrier for front side than for backside protonation, and this holds true for the majority of structures.

  11. DFT study of structure, IR and Raman spectra of the fluorescent "Janus" dendron built from cyclotriphosphazene core

    NASA Astrophysics Data System (ADS)

    Furer, V. L.; Vandyukova, I. I.; Vandyukov, A. E.; Fuchs, S.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

    2011-11-01

    The FTIR and FT-Raman spectra of the zero generation dendron, possessing five fluorescent dansyl terminal groups, cyclotriphosphazene core, and one carbamate function G0v were studied. The structural optimization and normal mode analysis were performed for G0v dendron on the basis of the density functional theory (DFT). The calculated geometrical parameters and harmonic vibrational frequencies are predicted in a good agreement with the experimental data. It was found that dendron molecule G0v has a concave lens structure with slightly non-planar cyclotriphosphazene core. The experimental IR and Raman spectra of G0v dendron were interpreted by means of potential energy distributions. Relying on DFT calculations a complete vibrational assignment is proposed. The frequency of ν(N-H) band in the IR spectrum reveal the presence of H-bonds in the G0v dendron.

  12. A study on fast reactor core mechanics by an ex-reactor test and comparisons with calculations

    SciTech Connect

    Tottori, Shoji; Kawanaka, Ikunori; Nakagawa, Masatoshi; Arie, Kazuo; Itoh, Kunihiro; Ohya, Takeaki; Motomiya, Takeo; Adachi, Hironori

    1996-07-01

    This paper presents and discusses the results of core bowing experiments performed with an ex-reactor rig holding a half hexagon array of 22 sub-assemblies (S/As) simulating the Japanese DFBR conditions and the comparisons of the measured results with calculations by individually developed codes--ARKAS, RAINBOW, SANBOW. The main conclusions of this study are (1) interwrapper loads and S/A displacements within the array were measured at selected positions for a series of five tests simulating the DFBR core bowing modes, (2) the overall comparison between the non-friction calculation and measurement showed good agreement for loads, displacements and their directions, and (3) validation of the friction algorithm has also been carried out and further improvement of the agreement was obtained.

  13. Direct laser-driven ramp compression studies of iron: A first step toward the reproduction of planetary core conditions

    NASA Astrophysics Data System (ADS)

    Amadou, N.; Brambrink, E.; Benuzzi-Mounaix, A.; Huser, G.; Guyot, F.; Mazevet, S.; Morard, G.; de Resseguier, T.; Vinci, T.; Myanishi, K.; Ozaki, N.; Kodama, R.; Boehly, T.; Henry, O.; Raffestin, D.; Koenig, M.

    2013-06-01

    The study of iron under quasi-isentropic compression using high energy lasers, might allow to understand its thermodynamical properties, in particular its melting line in conditions of pressure and temperature relevant to Earth-like planetary cores (330-1500 GPa, 5000-8000 K). However, the iron alpha-epsilon solid-solid phase transition at 13 GPa favors shock formation during the quasi-isentropic compression process which can depart from the appropriate thermodynamical path. Understanding this shock formation mechanism is a key issue for being able to reproduce Earth-like planetary core conditions in the laboratory by ramp compression. In this article, we will present recent results of direct laser-driven quasi-isentropic compression experiments on iron samples obtained on the LULI 2000 and LIL laser facilities.

  14. Design study of an air pump and integral lift engine ALF-504 using the Lycoming 502 core

    NASA Technical Reports Server (NTRS)

    Rauch, D.

    1972-01-01

    Design studies were conducted for an integral lift fan engine utilizing the Lycoming 502 fan core with the final MQT power turbine. The fan is designed for a 12.5 bypass ratio and 1.25:1 pressure ratio, and provides supercharging for the core. Maximum sea level static thrust is 8370 pounds with a specific fuel consumption of 0.302 lb/hr-lb. The dry engine weight without starter is 1419 pounds including full-length duct and sound-attenuating rings. The engine envelope including duct treatment but not localized accessory protrusion is 53.25 inches in diameter and 59.2 inches long from exhaust nozzle exit to fan inlet flange. Detailed analyses include fan aerodynamics, fan and reduction gear mechanical design, fan dynamic analysis, engine noise analysis, engine performance, and weight analysis.

  15. Contributions from geomagnetic inverse theory to the study of hydromagnetic conditions near the core-mantle boundary

    NASA Technical Reports Server (NTRS)

    Backus, George E.

    1991-01-01

    The Final Report on contributions from geomagnetic inverse theory to the study of hydromagnetic conditions near the core-mantle boundary (CMB) is presented. The original proposal was to study five questions concerning what the surface and satellite magnetic data imply about hydromagnetic and electromagnetic conditions near the CMB. The five questions are: (1) what do the surface and satellite data imply about the geomagnetic field B near the surface of the earth; (2) how does one extrapolate B down through the conducting mantle to the CMB; (3) if B on the CMB is visible, how accurately does it satisfy the frozen-flux approximation; (4) if frozen flux is a good approximation on the CMB, what can be inferred about the fluid velocity v in the upper core; and (5) if v at the CMB is visible, does it suggest any dynamical properties of the core, such as vertical advection, Alfven-inertial waves, link instabilities, or mantle effects. A summary of the research is provided.

  16. Theoretical and Experimental Studies of Epidermal Heat Flux Sensors for Measurements of Core Body Temperature.

    PubMed

    Zhang, Yihui; Webb, Richard Chad; Luo, Hongying; Xue, Yeguang; Kurniawan, Jonas; Cho, Nam Heon; Krishnan, Siddharth; Li, Yuhang; Huang, Yonggang; Rogers, John A

    2016-01-01

    Long-term, continuous measurement of core body temperature is of high interest, due to the widespread use of this parameter as a key biomedical signal for clinical judgment and patient management. Traditional approaches rely on devices or instruments in rigid and planar forms, not readily amenable to intimate or conformable integration with soft, curvilinear, time-dynamic, surfaces of the skin. Here, materials and mechanics designs for differential temperature sensors are presented which can attach softly and reversibly onto the skin surface, and also sustain high levels of deformation (e.g., bending, twisting, and stretching). A theoretical approach, together with a modeling algorithm, yields core body temperature from multiple differential measurements from temperature sensors separated by different effective distances from the skin. The sensitivity, accuracy, and response time are analyzed by finite element analyses (FEA) to provide guidelines for relationships between sensor design and performance. Four sets of experiments on multiple devices with different dimensions and under different convection conditions illustrate the key features of the technology and the analysis approach. Finally, results indicate that thermally insulating materials with cellular structures offer advantages in reducing the response time and increasing the accuracy, while improving the mechanics and breathability. PMID:25953120

  17. Structural Studies of Lipopolysaccharide-defective Mutants from Brucella melitensis Identify a Core Oligosaccharide Critical in Virulence.

    PubMed

    Fontana, Carolina; Conde-Álvarez, Raquel; Ståhle, Jonas; Holst, Otto; Iriarte, Maite; Zhao, Yun; Arce-Gorvel, Vilma; Hanniffy, Seán; Gorvel, Jean-Pierre; Moriyón, Ignacio; Widmalm, Göran

    2016-04-01

    The structures of the lipooligosaccharides fromBrucella melitensismutants affected in the WbkD and ManBcoreproteins have been fully characterized using NMR spectroscopy. The results revealed that disruption ofwbkDgives rise to a rough lipopolysaccharide (R-LPS) with a complete core structure (β-d-Glcp-(1→4)-α-Kdop-(2→4)[β-d-GlcpN-(1→6)-β-d-GlcpN-(1→4)[β-d-GlcpN-(1→6)]-β-d-GlcpN-(1→3)-α-d-Manp-(1→5)]-α-Kdop-(2→6)-β-d-GlcpN3N4P-(1→6)-α-d-GlcpN3N1P), in addition to components lacking one of the terminal β-d-GlcpN and/or the β-d-Glcpresidues (48 and 17%, respectively). These structures were identical to those of the R-LPS fromB. melitensisEP, a strain simultaneously expressing both smooth and R-LPS, also studied herein. In contrast, disruption ofmanBcoregives rise to a deep-rough pentasaccharide core (β-d-Glcp-(1→4)-α-Kdop-(2→4)-α-Kdop-(2→6)-β-d-GlcpN3N4P-(1→6)-α-d-GlcpN3N1P) as the major component (63%), as well as a minor tetrasaccharide component lacking the terminal β-d-Glcpresidue (37%). These results are in agreement with the predicted functions of the WbkD (glycosyltransferase involved in the biosynthesis of the O-antigen) and ManBcoreproteins (phosphomannomutase involved in the biosynthesis of a mannosyl precursor needed for the biosynthesis of the core and O-antigen). We also report that deletion ofB. melitensis wadCremoves the core oligosaccharide branch not linked to the O-antigen causing an increase in overall negative charge of the remaining LPS inner section. This is in agreement with the mannosyltransferase role predicted for WadC and the lack of GlcpN residues in the defective core oligosaccharide. Despite carrying the O-antigen essential inB. melitensisvirulence, the core deficiency in thewadCmutant structure resulted in a more efficient detection by innate immunity and attenuation, proving the role of the β-d-GlcpN-(1→6)-β-d-GlcpN-(1→4)[β-d-GlcpN-(1→6)]-β-d-GlcpN-(1→3)-α-d-Manp-(1→5) structure

  18. Structural Studies of Lipopolysaccharide-defective Mutants from Brucella melitensis Identify a Core Oligosaccharide Critical in Virulence*

    PubMed Central

    Fontana, Carolina; Conde-Álvarez, Raquel; Ståhle, Jonas; Holst, Otto; Iriarte, Maite; Zhao, Yun; Arce-Gorvel, Vilma; Hanniffy, Seán; Gorvel, Jean-Pierre; Moriyón, Ignacio; Widmalm, Göran

    2016-01-01

    The structures of the lipooligosaccharides from Brucella melitensis mutants affected in the WbkD and ManBcore proteins have been fully characterized using NMR spectroscopy. The results revealed that disruption of wbkD gives rise to a rough lipopolysaccharide (R-LPS) with a complete core structure (β-d-Glcp-(1→4)-α-Kdop-(2→4)[β-d-GlcpN-(1→6)-β-d-GlcpN-(1→4)[β-d-GlcpN-(1→6)]-β-d-GlcpN-(1→3)-α-d-Manp-(1→5)]-α-Kdop-(2→6)-β-d-GlcpN3N4P-(1→6)-α-d-GlcpN3N1P), in addition to components lacking one of the terminal β-d-GlcpN and/or the β-d-Glcp residues (48 and 17%, respectively). These structures were identical to those of the R-LPS from B. melitensis EP, a strain simultaneously expressing both smooth and R-LPS, also studied herein. In contrast, disruption of manBcore gives rise to a deep-rough pentasaccharide core (β-d-Glcp-(1→4)-α-Kdop-(2→4)-α-Kdop-(2→6)-β-d-GlcpN3N4P-(1→6)-α-d-GlcpN3N1P) as the major component (63%), as well as a minor tetrasaccharide component lacking the terminal β-d-Glcp residue (37%). These results are in agreement with the predicted functions of the WbkD (glycosyltransferase involved in the biosynthesis of the O-antigen) and ManBcore proteins (phosphomannomutase involved in the biosynthesis of a mannosyl precursor needed for the biosynthesis of the core and O-antigen). We also report that deletion of B. melitensis wadC removes the core oligosaccharide branch not linked to the O-antigen causing an increase in overall negative charge of the remaining LPS inner section. This is in agreement with the mannosyltransferase role predicted for WadC and the lack of GlcpN residues in the defective core oligosaccharide. Despite carrying the O-antigen essential in B. melitensis virulence, the core deficiency in the wadC mutant structure resulted in a more efficient detection by innate immunity and attenuation, proving the role of the β-d-GlcpN-(1→6)-β-d-GlcpN-(1→4)[β-d-GlcpN-(1→6)]-β-d-GlcpN-(1→3)-

  19. Cornerstones and Capstones: A Case Study on the Value of a Holistic Core in the Discipline of Communication Studies.

    ERIC Educational Resources Information Center

    Olsen, Richard K.; Weber, David E.; Trimble, Frank P.

    2002-01-01

    Argues for a holistic core that balances the dialectic tensions between social science and humanities, scholarly discipline and craft/praxis, and common and special topics within the discipline. Offers rationales for two other unique features of the University of North Carolina at Wilmington curriculum: research methods at the front end of the…

  20. Exploring effective core drug patterns in primary insomnia treatment with Chinese herbal medicine: study protocol for a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Chinese herbal medicine is one of the most popular Chinese medicine (CM) therapies for primary insomnia. One of the important characteristics of CM is that different Chinese clinicians give different prescriptions even for the same patient. However, there must be some fixed drug patterns in every clinician’s prescriptions. This study aims to screen the effective core drug patterns in primary insomnia treatment of three prestigious Chinese clinicians. Methods/design A triple-blind, randomized, placebo-controlled, parallel-group clinical trial will be performed. Three clinicians will diagnose and treat every eligible patient individually and independently, producing three prescriptions from three clinicians for every patient. Patients will equally be randomized to one of four groups – medical group A, medical group B, medical group C, or placebo group – and observed for efficacy of treatment. The sample will include primary insomnia patients meeting DSM IV-TR criteria, Spiegel scale score >18, and age 18 to 65 years. A sequential design is employed. Interim analysis will be conducted when between 80 and 160 patients complete the study. The interim study could be stopped and treated as final if a statistically significant difference between treatment and placebo groups can be obtained and core effective drug patterns can be determined. Otherwise, the study continues until the maximum sample size reaches 300. Treatment of the CM group is one of three Chinese clinicians’ prescriptions, who provide independently prescriptions based on their own CM theory and the patient’s disease condition. Assessment will be by sleep diary and Pittsburgh sleep quality index, and CM symptoms and signs will be measured. Primary outcome is total sleep time. Assessment will be carried out at the washout period, weeks 1, 2, 3, and 4 and 4th week after the end of treatment. Effectiveness analysis will be per intent to treat. A multi-dimension association rule and scale

  1. 100 Gbit/s WDM transmission at 2 µm: transmission studies in both low-loss hollow core photonic bandgap fiber and solid core fiber.

    PubMed

    Zhang, H; Kavanagh, N; Li, Z; Zhao, J; Ye, N; Chen, Y; Wheeler, N V; Wooler, J P; Hayes, J R; Sandoghchi, S R; Poletti, F; Petrovich, M N; Alam, S U; Phelan, R; O'Carroll, J; Kelly, B; Grüner-Nielsen, L; Richardson, D J; Corbett, B; Garcia Gunning, F C

    2015-02-23

    We show for the first time 100 Gbit/s total capacity at 2 µm waveband, using 4 × 9.3 Gbit/s 4-ASK Fast-OFDM direct modulation and 4 × 15.7 Gbit/s NRZ-OOK external modulation, spanning a 36.3 nm wide wavelength range. WDM transmission was successfully demonstrated over 1.15 km of low-loss hollow core photonic bandgap fiber (HC-PBGF) and over 1 km of solid core fiber (SCF). We conclude that the OSNR penalty associated with the SCF is minimal, while a ~1-2 dB penalty was observed after the HC-PBGF probably due to mode coupling to higher-order modes. PMID:25836529

  2. Lunar core: occam's razor?

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    Whether or not the earth's moon has a core is a much bandied question. Like many notions about the properties of the moon, ideas of a lunar core changed drastically after the Apollo studies. A review of the development of these ideas was given a scholarly treatment by S.K. Runcorn recently (Nature, 304, 589-596, 1983). In contrast, L.L. Hood, C.P. Sonett, and L.J. Srnka have questioned the concept in serious detail (Nature, 307, 661-662, 1984).Whether or not the moon actually has or has had a fluid metallic core is of great consequence for a number of geophysical theories about the solar system. Most investigators concede that the possible existence of a lunar core remains one of the major unanswered, and yet most critical, questions about the moon. A lot rides on the answer: Can a lunar-sized body have a core? Is the core metallic? How is the core related to lunar magnetism and its paleomagnetism? Is or was a lunar core related to lunar volcanism? If the moon can have a core, is planetary core formation in the solar system a simple matter of gravitationally segregating metallic fragments that were formed elsewhere? Implications of the questions are without limit. There is, perhaps, no more valid issue about the moon to explore scientifically.

  3. Fabrication and Pilot In Vivo Study of a Collagen-BDDGE-Elastin Core-Shell Scaffold for Tendon Regeneration

    PubMed Central

    Sandri, Monica; Filardo, Giuseppe; Kon, Elizaveta; Panseri, Silvia; Montesi, Monica; Iafisco, Michele; Savini, Elisa; Sprio, Simone; Cunha, Carla; Giavaresi, Gianluca; Veronesi, Francesca; Fini, Milena; Salvatore, Luca; Sannino, Alessandro; Marcacci, Maurilio; Tampieri, Anna

    2016-01-01

    The development of bio-devices for complete regeneration of ligament and tendon tissues is presently one of the biggest challenges in tissue engineering. Such device must simultaneously possess optimal mechanical performance, suitable porous structure, and biocompatible microenvironment. This study proposes a novel collagen-BDDGE-elastin (CBE)-based device for tendon tissue engineering, by the combination of two different modules: (i) a load-bearing, non-porous, “core scaffold” developed by braiding CBE membranes fabricated via an evaporative process and (ii) a hollow, highly porous, “shell scaffold” obtained by uniaxial freezing followed by freeze-drying of CBE suspension, designed to function as a physical guide and reservoir of cells to promote the regenerative process. Both core and shell materials demonstrated good cytocompatibility in vitro, and notably, the porous shell architecture directed cell alignment and population within the sample. Finally, a prototype of the core module was implanted in a rat tendon lesion model, and histological analysis demonstrated its safety, biocompatibility, and ability to induce tendon regeneration. Overall, our results indicate that such device may have the potential to support and induce in situ tendon regeneration. PMID:27446909

  4. Impact of post-manipulation corrective core exercises on the spinal deformation and lumbar strength in golfers: a case study

    PubMed Central

    Shin, Chul-ho; Kim, Minjeong; Park, Gi Duck

    2015-01-01

    [Purpose] This study examined spinal shape in professional golfers with chronic back pain, and analyzed the effects of a 4-week regimen of semi-weekly manipulation and corrective core exercises on spinal shape. [Subjects] Two golfers with chronic back pain. [Methods] The pelvis and spinal vertebrae were corrected using the Thompson “drop” technique. Angle and force were adjusted to place the pelvis, lumbar spine, and thoracic vertebrae in neutral position. The technique was applied twice weekly after muscle massage in the back and pelvic areas. The golfers performed corrective, warmup stretching exercises, followed by squats on an unstable surface using the Togu ball. They then used a gym ball for repetitions of hip rotation, upper trunk extension, sit-ups, and pelvic anterior-posterior, pelvic left-right, and trunk flexion-extension exercises. The session ended with cycling as a cool-down exercise. Each session lasted 60 minutes. [Results] The difference in height was measured on the left and right sides of the pelvic bone. The pelvic tilt changed significantly in both participants after the 4-week program. [Conclusion] In golfers, core muscles are critical and are closely related to spinal deformation. Core strengthening and spinal correction play a pivotal role in the correction of spinal deformation. PMID:26504350

  5. Time-resolved photoluminescence study of CdSe/CdMnS/CdS core/multi-shell nanoplatelets

    NASA Astrophysics Data System (ADS)

    Murphy, J. R.; Delikanli, S.; Scrace, T.; Zhang, P.; Norden, T.; Thomay, T.; Cartwright, A. N.; Demir, H. V.; Petrou, A.

    2016-06-01

    We used photoluminescence spectroscopy to resolve two emission features in CdSe/CdMnS/CdS and CdSe/CdS core/multi-shell nanoplatelet heterostructures. The photoluminescence from the magnetic sample has a positive circular polarization with a maximum centered at the position of the lower energy feature. The higher energy feature has a corresponding signature in the absorption spectrum; this is not the case for the low-energy feature. We have also studied the temporal evolution of these features using a pulsed-excitation/time-resolved photoluminescence technique to investigate their corresponding recombination channels. A model was used to analyze the temporal dynamics of the photoluminescence which yielded two distinct timescales associated with these recombination channels. The above results indicate that the low-energy feature is associated with recombination of electrons with holes localized at the core/shell interfaces; the high-energy feature, on the other hand, is excitonic in nature with the holes confined within the CdSe cores.

  6. A molecular dynamics study of the collective correlation functions of a hard-core fluid with a Yukawa tail

    NASA Astrophysics Data System (ADS)

    Alemany, M. M. G.; Rey, C.; Gallego, L. J.

    1996-11-01

    We present a molecular dynamics study of the collective correlation functions of a hard-core system with an attractive Yukawa tail, for various thermodynamic states in the fluid and liquid regions of the phase diagram. The results are compared with available information for hard spheres. The small-q behavior of the intermediate scattering functions indicates the propagation of sound waves, i.e., phononlike collective excitations, in the hard-core Yukawa system. The upper limit of q for these collective modes is practically independent of the thermodynamic state. The computed transverse current correlation functions show that at liquid densities the hard-core Yukawa system is able to sustain shear wave propagation above a critical q; the upper limit of q for sound waves and the lower limit for shear waves nearly coincide. All of these features are qualitatively similar to those found for hard spheres. However, there are significant quantitative differences, which reflect the influence of the attractive Yukawa tail on the dynamical behavior of the system.

  7. Fabrication and Pilot In Vivo Study of a Collagen-BDDGE-Elastin Core-Shell Scaffold for Tendon Regeneration.

    PubMed

    Sandri, Monica; Filardo, Giuseppe; Kon, Elizaveta; Panseri, Silvia; Montesi, Monica; Iafisco, Michele; Savini, Elisa; Sprio, Simone; Cunha, Carla; Giavaresi, Gianluca; Veronesi, Francesca; Fini, Milena; Salvatore, Luca; Sannino, Alessandro; Marcacci, Maurilio; Tampieri, Anna

    2016-01-01

    The development of bio-devices for complete regeneration of ligament and tendon tissues is presently one of the biggest challenges in tissue engineering. Such device must simultaneously possess optimal mechanical performance, suitable porous structure, and biocompatible microenvironment. This study proposes a novel collagen-BDDGE-elastin (CBE)-based device for tendon tissue engineering, by the combination of two different modules: (i) a load-bearing, non-porous, "core scaffold" developed by braiding CBE membranes fabricated via an evaporative process and (ii) a hollow, highly porous, "shell scaffold" obtained by uniaxial freezing followed by freeze-drying of CBE suspension, designed to function as a physical guide and reservoir of cells to promote the regenerative process. Both core and shell materials demonstrated good cytocompatibility in vitro, and notably, the porous shell architecture directed cell alignment and population within the sample. Finally, a prototype of the core module was implanted in a rat tendon lesion model, and histological analysis demonstrated its safety, biocompatibility, and ability to induce tendon regeneration. Overall, our results indicate that such device may have the potential to support and induce in situ tendon regeneration. PMID:27446909

  8. Material combinations and parametric study of thermal and mechanical performance of pyramidal core sandwich panels used for hypersonic aircrafts

    NASA Astrophysics Data System (ADS)

    Zhang, Ruiping; Zhang, Xiaoqing; Lorenzini, Giulio; Xie, Gongnan

    2016-07-01

    A novel kind of lightweight integrated thermal protection system, named pyramidal core sandwich panel, is proposed to be a good safeguard for hypersonic aircrafts in the current study. Such system is considered as not only an insulation structure but also a load-bearing structure. In the context of design for hypersonic aircrafts, an efficient optimization should be paid enough attention. This paper concerns with the homogenization of the proposed pyramidal sandwich core panel using two-dimensional model in subsequent research for material selection. According to the required insulation performance and thermal-mechanical properties, several suitable material combinations are chosen as candidates for the pyramidal core sandwich panel by adopting finite element analysis and approximate response surface. To obtain lightweight structure with an excellent capability of heat insulation and load-bearing, an investigation on some specific design variables, which are significant for thermal-mechanical properties of the structure, is performed. Finally, a good balance between the insulation performance, the capability of load-bearing and the lightweight has attained.

  9. DUBLIN CORE

    EPA Science Inventory

    The Dublin Core is a metadata element set intended to facilitate discovery of electronic resources. It was originally conceived for author-generated descriptions of Web resources, and the Dublin Core has attracted broad ranging international and interdisciplinary support. The cha...

  10. The USDA Barley Core Collection: Genetic Diversity, Population Structure, and Potential for Genome-Wide Association Studies

    PubMed Central

    Endelman, Jeffrey B.; Comadran, Jordi; Bonman, John M.; Bockelman, Harold E.; Chao, Shiaoman; Russell, Joanne; Waugh, Robbie; Hayes, Patrick M.; Muehlbauer, Gary J.

    2014-01-01

    New sources of genetic diversity must be incorporated into plant breeding programs if they are to continue increasing grain yield and quality, and tolerance to abiotic and biotic stresses. Germplasm collections provide a source of genetic and phenotypic diversity, but characterization of these resources is required to increase their utility for breeding programs. We used a barley SNP iSelect platform with 7,842 SNPs to genotype 2,417 barley accessions sampled from the USDA National Small Grains Collection of 33,176 accessions. Most of the accessions in this core collection are categorized as landraces or cultivars/breeding lines and were obtained from more than 100 countries. Both STRUCTURE and principal component analysis identified five major subpopulations within the core collection, mainly differentiated by geographical origin and spike row number (an inflorescence architecture trait). Different patterns of linkage disequilibrium (LD) were found across the barley genome and many regions of high LD contained traits involved in domestication and breeding selection. The genotype data were used to define ‘mini-core’ sets of accessions capturing the majority of the allelic diversity present in the core collection. These ‘mini-core’ sets can be used for evaluating traits that are difficult or expensive to score. Genome-wide association studies (GWAS) of ‘hull cover’, ‘spike row number’, and ‘heading date’ demonstrate the utility of the core collection for locating genetic factors determining important phenotypes. The GWAS results were referenced to a new barley consensus map containing 5,665 SNPs. Our results demonstrate that GWAS and high-density SNP genotyping are effective tools for plant breeders interested in accessing genetic diversity in large germplasm collections. PMID:24732668

  11. Study on the synthesis of the cyclopenta[f]indole core of raputindole A.

    PubMed

    Marsch, Nils; Kock, Mario; Lindel, Thomas

    2016-01-01

    The raputindoles from the rutaceous tree Raputia simulans share a cyclopenta[f]indole partial structure the synthesis of which is subject of this investigation. An efficient route to a series of 1,5-di(indol-6-yl)pentenones was developed via Mo/Au-catalyzed Meyer-Schuster rearrangement of tertiary propargylic alcohol precursors. However, none of the enones underwent the desired Nazarov cyclization to a cyclopenta[f]indole. More suitable were 6-hydroxyallylated indolines which gave good yields of cyclopenta[f]indolines after treatment with SnCl4, as soon as sterically demanding β-cyclocitral adducts were reacted. Most successful were Pt(II) and Au(I)-catalyzed cyclizations of N-TIPS-protected indolin-6-yl-substituted propargylacetates which provided the hydrogenated tricyclic cyclopenta[f]indole core system in high yield. PMID:26977193

  12. An experimental and theoretical core-level study of tautomerism in guanine.

    PubMed

    Plekan, Oksana; Feyer, Vitaliy; Richter, Robert; Coreno, Marcello; Vall-Llosera, Gemma; Prince, Kevin C; Trofimov, Alexander B; Zaytseva, Irina L; Moskovskaya, Tatyana E; Gromov, Evgeniy V; Schirmer, Jochen

    2009-08-20

    The core level photoemission and near edge X-ray photoabsorption spectra of guanine in the gas phase have been measured and the results interpreted with the aid of high level ab initio calculations. Tautomers are clearly identified spectroscopically, and their relative free energies and Boltzmann populations at the temperature of the experiment (600 K) have been calculated and compared with the experimental results and with previous calculations. We obtain good agreement between experiment and the Boltzmann weighted theoretical photoemission spectra, which allows a quantitative determination of the ratio of oxo to hydroxy tautomer populations. For the photoabsorption spectra, good agreement is found for the C 1s and O 1s spectra but only fair agreement for the N 1s edge. PMID:19634878

  13. Core compressor exit stage study. Volume 1: Blading design. [turbofan engines

    NASA Technical Reports Server (NTRS)

    Wisler, D. C.

    1977-01-01

    A baseline compressor test stage was designed as well as a candidate rotor and two candidate stators that have the potential of reducing endwall losses relative to the baseline stage. These test stages are typical of those required in the rear stages of advanced, highly-loaded core compressors. The baseline Stage A is a low-speed model of Stage 7 of the 10 stage AMAC compressor. Candidate Rotor B uses a type of meanline in the tip region that unloads the leading edge and loads the trailing edge relative to the baseline Rotor A design. Candidate Stator B embodies twist gradients in the endwall region. Candidate Stator C embodies airfoil sections near the endwalls that have reduced trailing edge loading relative to Stator A. Tests will be conducted using four identical stages of blading so that the designs described will operate in a true multistage environment.

  14. Self-consistent-field studies of core-level shifts in ionic crystals: LiF

    SciTech Connect

    Broughton, J.Q.; Bagus, P.S.

    1984-10-15

    Restricted-Hartree-Fock, self-consistent-field calculations have been performed for the ground and ionic states of clusters of lithium and fluorine atoms. These clusters are appropriately charged to represent an Li/sup +/F/sup -/ ionic crystal and point charges are used to represent the Madelung field due to ions not explicitly included in the cluster. Factors giving rise to core- and valence-level binding-energy shifts have been examined and separated into compressional, relaxational, and effective Madelung contributions. Many tests of ionicity are shown to be well satisfied, although this is often caused by fortuitous cancellations. Extra-ionic relaxation energies on both the cation and anion are shown to be small, and shakeup probabilities are calculated.

  15. Core design study of a supercritical light water reactor with double row fuel rods

    SciTech Connect

    Zhao, C.; Wu, H.; Cao, L.; Zheng, Y.; Yang, J.; Zhang, Y.

    2012-07-01

    An equilibrium core for supercritical light water reactor has been designed. A novel type of fuel assembly with dual rows of fuel rods between water rods is chosen and optimized to get more uniform assembly power distributions. Stainless steel is used for fuel rod cladding and structural material. Honeycomb structure filled with thermal isolation is introduced to reduce the usage of stainless steel and to keep moderator temperature below the pseudo critical temperature. Water flow scheme with ascending coolant flow in inner regions is carried out to achieve high outlet temperature. In order to enhance coolant outlet temperature, the radial power distributions needs to be as flat as possible through operation cycle. Fuel loading pattern and control rod pattern are optimized to flatten power distribution at inner regions. Axial fuel enrichment is divided into three parts to control axial power peak, which affects maximum cladding surface temperature. (authors)

  16. Carbon combustion supernovae - Numerical studies of the final evolution of degenerate carbon-oxygen cores

    NASA Technical Reports Server (NTRS)

    Mueller, E.; Arnett, W. D.

    1986-01-01

    The evolution of polytropic 1.46-solar-mass 3-Gg/cu cm (4 x 10 to the 8th)-K pure C cores is investigated theoretically by means of model computations starting from the runaway stage. The temperature in central zones is raised to the runaway temperature, and the evolution is followed in a spherical coordinate system. In models of burning without detonation, it is found that the initially spherical burning front is Rayleigh-Taylor unstable, without bipolar jets or equatorial rings; that some C is not burned to Ni; and that the Ni in the 0.8-1.0 solar mass of burned fuel produced can account for observed properties of type I supernovae.

  17. Study on the synthesis of the cyclopenta[f]indole core of raputindole A

    PubMed Central

    Marsch, Nils; Kock, Mario

    2016-01-01

    Summary The raputindoles from the rutaceous tree Raputia simulans share a cyclopenta[f]indole partial structure the synthesis of which is subject of this investigation. An efficient route to a series of 1,5-di(indol-6-yl)pentenones was developed via Mo/Au-catalyzed Meyer–Schuster rearrangement of tertiary propargylic alcohol precursors. However, none of the enones underwent the desired Nazarov cyclization to a cyclopenta[f]indole. More suitable were 6-hydroxyallylated indolines which gave good yields of cyclopenta[f]indolines after treatment with SnCl4, as soon as sterically demanding β-cyclocitral adducts were reacted. Most successful were Pt(II) and Au(I)-catalyzed cyclizations of N-TIPS-protected indolin-6-yl-substituted propargylacetates which provided the hydrogenated tricyclic cyclopenta[f]indole core system in high yield. PMID:26977193

  18. From hypernuclei to the Inner Core of Neutron Stars: A Quantum Monte Carlo Study

    NASA Astrophysics Data System (ADS)

    Lonardoni, D.; Pederiva, F.; Gandolfi, S.

    2014-08-01

    Auxiliary Field Diffusion Monte Carlo (AFDMC) calculations have been employed to revise the interaction beween A-hyperons and nucleons in hypernuclei. The scheme used to describe the interaction, inspired by the phenomenological Argonne-Urbana forces, is the ΛN + ΛNN potential firstly introduced by Bodmer, Usmani et al. Within this framework, we performed calculations on light and medium mass hypernuclei in order to assess the extent of the repulsive contribution of the three-body part. By tuning this contribution in order to reproduce the Λ separation energy in 5ΛHe and 17ΛO, experimental findings are reproduced over a wide range of masses. Calculations have then been extended to Λ-neutron matter in order to derive an analogous of the symmetry energy to be used in determining the equation of state of matter in the typical conditions found in the inner core of neutron stars.

  19. AN Core Analysis

    NASA Astrophysics Data System (ADS)

    Barbarino, Andrea; Tomatis, Daniele

    2014-06-01

    Several alternative approximations of neutron transport have been proposed in years to move around the known limitations imposed by neutron diffusion in the modeling of nuclear cores. However, only a few complied with the industrial requirements of fast numerical computation, concentrating more on physical accuracy. In this work, the AN transport methodology is discussed with particular interest in core performance calculations. The implementation of the methodology in full core codes is discussed with particular attention to numerical issues and to the integration within the entire simulation process. Finally, first results from core studies in AN transport are analyzed in detail and compared to standard results of neutron diffusion.

  20. A subarcsecond study of the hot molecular core in G023.01-00.41

    NASA Astrophysics Data System (ADS)

    Sanna, A.; Cesaroni, R.; Moscadelli, L.; Zhang, Q.; Menten, K. M.; Molinari, S.; Caratti o Garatti, A.; De Buizer, J. M.

    2014-05-01

    Context. Searching for disk-outflow systems in massive star-forming regions is a key to assessing the main physical processes in the recipe of massive star formation. Aims: We have selected a hot molecular core (HMC) in the high-mass star-forming region G023.01-00.41, where VLBI multi-epoch observations of water and methanol masers have suggested the existence of rotation and expansion within 2000 AU of its center. Our purpose is to image the thermal line and continuum emission at millimeter wavelengths to establish the physical parameters and velocity field of the gas in the region. Methods: We performed SMA observations at 1.3 mm with both the most extended and compact array configurations, providing subarcsecond and high sensitivity maps of various molecular lines, including both hot-core and outflow tracers. We also reconstructed the spectral energy distribution of the region from millimeter to near infrared wavelengths, using the Herschel/Hi-GAL maps, as well as archival data. Results: From the spectral energy distribution, we derive a bolometric luminosity of ~4 × 104 L⊙. Our interferometric observations reveal that the distribution of dense gas and dust in the HMC is significantly flattened and extends up to a radius of 8000 AU from the center of radio continuum and maser emission in the region. The equatorial plane of this HMC is strictly perpendicular to the elongation of the collimated bipolar outflow, as imaged on scales of ~0.1-0.5 pc in the main CO isotopomers, as well as in the SiO(5-4) line. In the innermost HMC regions (≲1000 AU), the velocity field traced by the CH3CN (12K - 11K) line emission shows that molecular gas is both expanding along the outflow direction following a Hubble law and rotating about the outflow axis, in agreement with the (3D) velocity field traced by methanol masers. The velocity field associated with rotation indicates a dynamical mass of ~19 M⊙ at the center of the core. The latter is likely to be concentrated in a

  1. A study of the core of the Shapley concentration. II. ROSAT observation of A 3558.

    NASA Astrophysics Data System (ADS)

    Bardelli, S.; Zucca, E.; Malizia, A.; Zamorani, G.; Scaramella, R.; Vettolani, G.

    1996-01-01

    We present the results of a pointed ROSAT PSPC observation of the Abell cluster A 3558. A 3558 is the only cluster classified as richness class four in the entire ACO catalogue and, together with A 3556 and A 3562, it is part of an elongated structure defining the core of the Shapley Concentration. The X-ray surface brightness distribution of the cluster can be fitted as the sum of two components: an elliptical King law, with a major core radius of ~0.20h^-1^Mpc and an axial ratio ~0.72, and a Gaussian central source associated with the cD galaxy. The centers of the two X-ray components are separated by 75 arcsec, corresponding to ~50h^-1^kpc. A number of additional discrete sources is also present in the field. Although most of them are probably unrelated to the cluster, two of these sources are identified with the poor clusters SC 1327-312 and SC 1329-313, at approximately the same redshift as A 3558, and two other sources are identified with bright galaxies, which are also part of the core of the Shapley Concentration. In addition, there is also evidence of an enhanced diffuse X-ray emission which connects the outer part of A 3558 with SC 1327-312. From the spectral analysis, we find that the temperature profile of A 3558 is consistent with an isothermal distribution at kT~3.25keV, while the cD galaxy has the lower temperature kT=1.89keV. For the cluster we derive a luminosity L_X_=1.1x10^44^h^-2^erg/s, in the energy range [0.5-2.0]keV, within a radius of 0.8h^-1^Mpc and a total mass M_tot_=3.1x10^14^h^-1^Msun_ within an Abell radius (1.5h^-1^Mpc). In the same region the gas mass is ~20%h^-3/2^ of the total mass and there are evidences for the hot gas to be less centrally concentrated than the dark matter and the stellar component. For h=1 most of the dynamical mass is in dark matter, while for h=0.5 most of the mass is in hot gas. In both cases, the stellar mass appears to be a good tracer of the total mass distribution. The derived M/L ratio is ~130h

  2. Constraints on core formation from systematic study of metal-silicate partitioning on a great number of siderophile elements

    SciTech Connect

    Siebert, J; Ryerson, F J

    2008-10-27

    The abundances of siderophile elements in the Earth's mantle are the result of core formation in the early Earth. Many variables are involved in the prediction of metal/silicate siderophile partition coefficients during core segregation: pressure, temperature, oxygen fugacity, silicate and metal compositions. Despite publications of numerous results of metal-silicate experiments, the experimental database and predictive expressions for elements partitioning are hampered by a lack of systematic study to separate and evaluate the effects of each variable. Only a relatively complete experimental database that describes Ni and Co partitioning now exists but is not sufficient to unambiguously decide between the most popular model for core formation with a single stage core-mantle equilibration at the bottom of a deep magma ocean (e.g. Li and Agee, 2001) and more recent alternative models (e.g. Wade and Wood, 2005; Rubie et al., 2007). In this experimental work, systematic study of metal silicate partitioning is presented for elements normally regarded as moderately siderophile (Mo, As, Ge, W, P, Ni, Co), slightly siderophile (Zn, Ga, Mn, V, Cr) and refractory lithophile (Nb, Ta). Using a new piston-cylinder design assembly allows us to present a suite of isobaric partitioning experiments at 3 GPa within a temperature range from 1600 to 2600 C and over a range of relative oxygen fugacity from IW-1.5 to IW-3.5. Silicate melts range from basaltic to peridotite in composition. The individual effect of pressure is also investigated through a combination of piston cylinder and multi anvil isothermal experiments from 0.5 to 18 GPa at 1900 C. Absolute measurements of partitioning coefficients combining EMP and LA-ICPMS analytical methods are provided. New results are obtained for elements whose partitioning behavior is usually poorly constrained and not integrated into any accretion or core formation models. We find notably that Ge, As, Mo become less siderophile with

  3. Making an Ice Core.

    ERIC Educational Resources Information Center

    Kopaska-Merkel, David C.

    1995-01-01

    Explains an activity in which students construct a simulated ice core. Materials required include only a freezer, food coloring, a bottle, and water. This hands-on exercise demonstrates how a glacier is formed, how ice cores are studied, and the nature of precision and accuracy in measurement. Suitable for grades three through eight. (Author/PVD)

  4. Gate field induced switching of electronic current in Si-Ge Core-Shell nanowire quantum dots: A first principles study

    NASA Astrophysics Data System (ADS)

    Dhungana, Kamal B.; Jaishi, Meghnath; Pati, Ranjit

    Core-shell nanowires are formed by varying the radial composition of the nanowires. One of the most widely studied core-shell nanowire groups in recent years is the Si-Ge and Ge-Si core-shell nanowires. Compared to their pristine counterparts, they are reported to have superior electronic properties. For example, the scaled ON state current value in a Ge-Si core-shell nanowire field effect transistor (FET) is reported to be three to four times higher than that observed in state-of-the-art-metal oxide semiconductor FET (MOSFET) (Nature, 441, 489 (2006)). Here, we study the transport properties of the pristine Si and Si-Ge core-shell nanowire quantum dots of similar dimension to understand the superior performance of Si-Ge core-shell nanowire field effect transistor. Our calculations yield excellent gate field induced switching behavior in current for both pristine Si and Si-Ge core-shell hetero-structure nanowire quantum dots. The threshold gate bias for ON/OFF switching in the Si-Ge core-shell nanowire is found to be much smaller than that found in the pristine Si nanowire. A single particle many-body Green's function approach in conjunction with density functional theory is employed to calculate the electronic current.

  5. Study of laser-induced damage to large core silica fiber by Nd:YAG and Alexandrite lasers

    NASA Astrophysics Data System (ADS)

    Sun, Xiaoguang; Li, Jie; Hokansson, Adam; Whelan, Dan; Clancy, Michael

    2009-02-01

    As a continuation of our earlier study at 2.1 μm wavelength, we have investigated the laser damage to several types of step-index, large core (1500 μm) silica fibers at two new wavelengths by high power long pulsed Nd:YAG (1064 nm) and Alexandrite (755 nm) lasers. It was observed that fibers with different designs showed a significant difference in performance at these wavelengths. We will also report a correlation of damage to the fibers between the two laser wavelengths. The performance analyses of different fiber types under the given test conditions will enable optimization of fiber design for specific applications.

  6. Study of Fast, Near-Infrared Photodetectors for the ITER Core LIDAR Thomson Scattering

    SciTech Connect

    Giudicotti, L.; Beurskens, M.; Kempenaars, M.; Walsh, M. J.

    2008-03-12

    A key component for the ITER core LIDAR Thomson Scattering (TS) diagnostic would be a detector with good sensitivity in the 850-1060 nm near infrared (NIR) spectral region. Covering this spectral region becomes necessary if a Nd:YAG laser system operating at {lambda} = 1.06 {mu}m is used as the laser source, which is a very attractive choice in terms of available energy, repetition rate, reliability and cost. In this paper we review the state of the art of two types of detectors available for the above spectral range: the transferred electron (TE) InGaAs/InP hybrid photodiode and the In{sub x}Ga{sub 1-x}As microchannel plate (MCP) image intensifier and we describe the advancements necessary for a possible application in the ITER LIDAR TS. In addition we describe the preliminary characterization of new GaAsP fast MCP photomultipliers (PMTs) suitable for the detection of the visible part of the LIDAR TS spectrum in JET and ITER.

  7. Diagenesis of bank margin carbonates monitors glacio-eustacy: modeling and core study results

    SciTech Connect

    Matthews, R.K.; Al-Saqri, K.; Frohlich, C.

    1985-01-01

    Subsiding bank margin carbonates provide a monitoring system for high frequency sea level fluctuations. When sea level rises, new reefs and skeletal sands accumulate to near high-stand sea level. When sea level falls, subaerial exposure and related meteoric and mixed water diagenesis rapidly impart their mineralogic, isotopic, chemical, and petrographic signature on the strata. The authors model the interaction of fluctuating sea level (Milankovitch frequencies) and subsiding bank margin carbonates. Characteristic diagenetic lithologies occur seemingly randomly interbedded and unrelatable to specific subaerial exposure surfaces. This is similar to the pattern observed in Eocene bank margin skeletal sands of Kirkuk Field, Iraq. Meteoric diagenesis dominates the upper 35 meters of the authors core. The next 85 meters contain randomly alternating beds of meteoric limestone, mixed water dolomite, and limestone with well-preserved skeletal grains. This sequence is consistent with rapid glacio-eustatic fluctuations of Late Eocene sea level followed by a 35 to 50 meter glacio-eustatic lowering of average sea level at or near Eocene/Oligocene boundary.

  8. Polar structure in a ferroelectric bent-core mesogen as studied by second-harmonic generation

    NASA Astrophysics Data System (ADS)

    Araoka, Fumito; Thisayukta, Jirakorn; Ishikawa, Ken; Watanabe, Junji; Takezoe, Hideo

    2002-08-01

    Second-harmonic generation (SHG) measurements have been conducted in the ferroelectric liquid crystalline phase of a chiral bent-core molecule, P-8-OPIMB6*. Well-aligned cells were obtained by applying an electric field parallel to the substrate surfaces. In-plane anisotropy of the SHG signal observed at normal incidence of light shows two- or four-leaf patterns depending on polarization conditions, indicating a ferroelectric uniform structure. The detailed analysis of the data by taking account of optical anisotropy in the SHG active bulk leads to the determination of nonlinear susceptibility tensor components, d333=14.4 pm/V and d311=49.2 pm/V. Using the d coefficients thus determined, the hyperpolarizability tensor components of the molecule are also determined as βzzz=14.5×10-30 esu and βzxx=67.6×10-30 esu. These values well agree with those of the achiral homolog P-12-OPIMB previously determined by hyper-Rayleigh scattering.

  9. Polar structure in a ferroelectric bent-core mesogen as studied by second-harmonic generation.

    PubMed

    Araoka, Fumito; Thisayukta, Jirakorn; Ishikawa, Ken; Watanabe, Junji; Takezoe, Hideo

    2002-08-01

    Second-harmonic generation (SHG) measurements have been conducted in the ferroelectric liquid crystalline phase of a chiral bent-core molecule, P-8-OPIMB6*. Well-aligned cells were obtained by applying an electric field parallel to the substrate surfaces. In-plane anisotropy of the SHG signal observed at normal incidence of light shows two- or four-leaf patterns depending on polarization conditions, indicating a ferroelectric uniform structure. The detailed analysis of the data by taking account of optical anisotropy in the SHG active bulk leads to the determination of nonlinear susceptibility tensor components, d(333)=14.4 pm/V and d(311)=49.2 pm/V. Using the d coefficients thus determined, the hyperpolarizability tensor components of the molecule are also determined as beta(zzz)=14.5 x 10(-30) esu and beta(zxx)=67.6 x 10(-30) esu. These values well agree with those of the achiral homolog P-12-OPIMB previously determined by hyper-Rayleigh scattering. PMID:12241194

  10. Study on synthesis of ultrafine Cu-Ag core-shell powders with high electrical conductivity

    NASA Astrophysics Data System (ADS)

    Peng, Yu-hsien; Yang, Chih-hao; Chen, Kuan-ting; Popuri, Srinivasa R.; Lee, Ching-Hwa; Tang, Bo-Shin

    2012-12-01

    Cu-Ag composite powders with high electrical conductivity were synthesized by electroless plating of silver sulfate, copper powders with eco-friendly sodium citrate as reducing agent, dispersant and chelating agent in an aqueous system. The influences of sodium citrate/Ag ratio on Ag coatings of Cu powders were investigated. Ag was formed a dense coating on the surface of Cu powders at a molar ratio of sodium citrate/Ag = 0.07/1. SEM showed an uniformity of Ag coatings on Cu powders. SEM-EDX also revealed that Cu cores were covered by Ag shells on the whole. The surface composition analysis by XPS indicated that without Cu or Ag atoms in the surface were oxidized. The resistivity measurements of Cu-Ag paste shows that they have closer resistivity as the pure silver paste's after 250 °C for 30 min heat-treatment (2.55 × 10-4 Ω cm) and 350 °C for 30 min heat-treatment (1.425 × 10-4 Ω cm).

  11. Study of the resonant scattering in the Perseus cluster core with ASTRO-H SXS

    NASA Astrophysics Data System (ADS)

    Konami, Saori; Sato, Kosuke; Ohashi, Takaya; Churazov, Eugene; Zhuravleva, Irina; Sunyaev, Rashid

    Resonance lines from cores of galaxy clusters have significant optical depth, as predicted by Gilfanov, Sunyaev & Churazov (1987). We can constrain turbulence velocity from the level of suppression of the resonance lines, providing a good measure of dynamical condition of gas. The Soft X-ray Spectrometer (SXS) onboard ASTRO-H is a high-resolution spectrometer and capable of separating resonance lines from other line components. It is important to estimate the flux contamination due to the point spread function (PSF) of the X-ray telescope ~1.5’. Zhuravleva et al. (2013) constructed spectral models for the Perseus cluster which took into account modifications of line fluxes and shapes due to the resonant scattering effect as well as by radial variations of density, temperature and abundances of heavy elements. Line broadening by small-scale motions were also included. We performed simulation of these models by taking into account the pixel layout of SXS and PSF effect. The suppression of resonance line from H-like Fe will enable us to constrain gas velocities below 300 km/sec.

  12. Harmonising data collection from osteoarthritis studies to enable stratification: recommendations on core data collection from an Arthritis Research UK clinical studies group

    PubMed Central

    Corp, Nadia; Watt, Fiona E.; Felson, David T.; O’Neill, Terence W.; Holt, Cathy A.; Jones, Richard K.; Conaghan, Philip G.; Arden, Nigel K.

    2016-01-01

    Objective. Treatment of OA by stratifying for commonly used and novel therapies will likely improve the range of effective therapy options and their rational deployment in this undertreated, chronic disease. In order to develop appropriate datasets for conducting post hoc analyses to inform approaches to stratification for OA, our aim was to develop recommendations on the minimum data that should be recorded at baseline in all future OA interventional and observational studies. Methods. An Arthritis Research UK study group comprised of 32 experts used a Delphi-style approach supported by a literature review of systematic reviews to come to a consensus on core data collection for OA studies. Results. Thirty-five systematic reviews were used as the basis for the consensus group discussion. For studies with a primary structural endpoint, core domains for collection were defined as BMI, age, gender, racial origin, comorbidities, baseline OA pain, pain in other joints and occupation. In addition to the items generalizable to all anatomical sites, joint-specific domains included radiographic measures, surgical history and anatomical factors, including alignment. To demonstrate clinical relevance for symptom studies, the collection of mental health score, self-efficacy and depression scales were advised in addition to the above. Conclusions. Currently it is not possible to stratify patients with OA into therapeutic groups. A list of core and optional data to be collected in all OA interventional and observational studies was developed, providing a basis for future analyses to identify predictors of progression or response to treatment. PMID:27084310

  13. A study of core Thomson scattering measurements in ITER using a multi-laser approach

    NASA Astrophysics Data System (ADS)

    Kurskiev, G. S.; Sdvizhenskii, P. A.; Bassan, M.; Andrew, P.; Bazhenov, A. N.; Bukreev, I. M.; Chernakov, P. V.; Kochergin, M. M.; Kukushkin, A. B.; Kukushkin, A. S.; Mukhin, E. E.; Razdobarin, A. G.; Samsonov, D. S.; Semenov, V. V.; Tolstyakov, S. Yu.; Kajita, S.; Masyukevich, S. V.

    2015-05-01

    The electron component is the main channel for anomalous power loss and the main indicator of transient processes in the tokamak plasma. The electron temperature and density profiles mainly determine the operational mode of the machine. This imposes demanding requirements on the precision and on the spatial and temporal resolution of the Thomson scattering (TS) measurements. Measurements of such high electron temperature with good accuracy in a large fusion device such as ITER using TS encounter a number of physical problems. The 40 keV TS spectrum has a significant blue shift. Due to the transmission functions of the fibres and to their darkening that can occur under a strong neutron irradiation, the operational wavelength range is bounded on the blue side. For example, high temperature measurements become impossible with the 1064 nm probing wavelength since the TS signal within the boundaries of the operational window weakly depends on Te. The second problem is connected with the TS calibration. The TS system for a large fusion machine like ITER will have a set of optical components inaccessible for maintenance, and their spectral characteristics may change with time. Since the present concept of the TS system for ITER relies on the classical approach to measuring the shape of the scattered spectra using wide spectral channels, the diagnostic will be very sensitive to the changes in the optical transmission. The third complication is connected with the deviation of the electron velocity distribution function from a Maxwellian that can happen under a strong ECRH/ECCD, and it may additionally hamper the measurements. This paper analyses the advantages of a ‘multi-laser approach’ implementation for the current design of the core TS system. Such an approach assumes simultaneous plasma probing with different wavelengths that allows the measurement accuracy to be improved significantly and to perform the spectral calibration of the TS system. Comparative analysis

  14. Luminescence, lifetime, and quantum yield studies of redispersible Eu3+-doped GdPO4 crystalline nanoneedles: Core-shell and concentration effects

    NASA Astrophysics Data System (ADS)

    Yaiphaba, N.; Ningthoujam, R. S.; Singh, N. Shanta; Vatsa, R. K.; Singh, N. Rajmuhon; Dhara, Sangita; Misra, N. L.; Tewari, R.

    2010-02-01

    Crystalline nanoneedles of Eu3+-doped GdPO4 and Eu3+-doped GdPO4 covered with GdPO4 shell (core shell) have been prepared at relatively low temperature of 150 °C in ethylene glycol medium. From luminescence study, asymmetric ratio of Eu3+ emission at 612 nm (electric dipole transition) to 592 nm (magnetic dipole transition) is found to be less than one. Maximum luminescence was observed from the nanoparticles with Eu3+ concentration of 5 at. %. For a fixed concentration of Eu3+ doping, there is an improvement in emission intensity for core-shell nanoparticles compared to that for core. This has been attributed to effective removal of surface inhomogeneities around Eu3+ ions present on the surface of core as well as the passivation of inevitable surface states, defects or capping ligand (ethylene glycol) of core nanoparticles by bonding to the shell. Lifetime for D50 level of Eu3+ was found to increase three times for core-shell nanoparticles compared to that for core confirming the more Eu3+ ions with symmetry environment in core shell. For 5 at. % Eu3+-doped GdPO4, quantum yield of 19% is obtained. These nanoparticles are redispersible in water, ethanol, or chloroform and thus will be useful in biological labeling. The dispersed particles are incorporated in polymer-based films that will be useful in display devices.

  15. 24. A CORE WORKER DISPLAYS THE CORE BOX AND CORES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. A CORE WORKER DISPLAYS THE CORE BOX AND CORES FOR A BRASS GATE VALVE BODY MADE ON A CORE BOX, CA. 1950. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  16. Satellite infrared observations of Kuroshio warm-core rings and their application to study of Pacific saury migration

    NASA Astrophysics Data System (ADS)

    Saitoh, Sei-ichi; Kosaka, Sunao; Iisaka, Joji

    1986-11-01

    Satellite infrared observations of Kuroshio warm-core rings (KWCRs), made in the Tohoku area west of 150°E from February 1980 to June 1981, were used to study the effect of ring distributions on the migration routes of the epi-pelagic and migratory fish Pacific saury. Cololabis saira (Brevoort). The movement and mean speed of three KWCRs and a Tsugaru warm current gyre were determined in the study area. KWCRs tended to drift to the north or to the east at a mean speed of 5 cm s -1. This drift speed is similar to that of Gulf Stream warm-core rings, but the drift direction is quite different from the westward drift in the Gulf Stream system. A comparison between distribution of KWCRs and distribution of fish schools suggests that the KWCRs control southward migration routes of Pacific saury through interaction with the surrounding cold waters such as the First and Second Oyashio Intrusions. Satellite infrared monitoring of KWCRs and the surrounding cold waters have proved to be useful for the short period prediction of Pacific saury fishing ground formation.

  17. A case study of full integration of the arts into core subject area instruction in one East Texas secondary school

    NASA Astrophysics Data System (ADS)

    Leysath, Maggie

    This exploratory phenomenological case study investigated the influence the full integration of the arts into core subject instruction has on classroom environment, student academic achievement, and student engagement as perceived by administrators, teachers, and students in one East Texas secondary school. Participant interviews were analyzed using Creswell's (2012) six-step method for analyzing phenomenological studies. The researcher implemented three learning activities in which ceramics learning objectives were fully integrated with chemistry learning objectives. The first activity combined clay properties and pottery wheel throwing with significant numbers. The second activity combined glaze formulation with moles. The third combined stoichiometry with the increased glaze formula for students to glaze the bowls they made. Findings suggest the full integration of art in core subject area instruction has numerous positive effects. Participants reported improved academic achievement for all students including reluctant learners. Students, teachers, and the administrator reported greater participation in the art integrated activities. Participants perceived a need for further training for teachers and administrators for greater success.

  18. The dynamic mechanical properties study on the sandwich panel of different thickness steel plate-foam aluminum core

    NASA Astrophysics Data System (ADS)

    Chang, Zhongliang; Zou, Guangping; Zhao, Weiling; Xia, Peixiu

    2009-12-01

    The foam aluminum belongs to multi-cell materials, and it has good mechanical performance, such as large deformation capacity and good energy absorption, and usually used as core material of sandwich panel, now it is widely used in automotive, aviation, aerospace and other fields, particularly suitable for various anti-collision structure and buffer structure. In this article, based on an engineering background, the INSTRON4505 electronic universal testing machine and split Hopkinson pressure bar (SHPB) were used for testing the static and dynamic mechanical properties of sandwich panel with different thickness steel plate- foam aluminum core, from the results we can see that the steel plate thickness has big influence on the stress-strain curve of the sandwich panel, and also takes the sandwich panel with 1mm steel panel to study the material strain rate dependence which under different high shock wave stress loaded, the results show that the sandwich panel is strain rate dependence material. And also, in order to get good waveforms in the SHPB experiment, the waveform shaped technique is used in the dynamic experiments, and the study of this paper will good to sandwich panel used in the engineering.

  19. The dynamic mechanical properties study on the sandwich panel of different thickness steel plate-foam aluminum core

    NASA Astrophysics Data System (ADS)

    Chang, Zhongliang; Zou, Guangping; Zhao, Weiling; Xia, Peixiu

    2010-03-01

    The foam aluminum belongs to multi-cell materials, and it has good mechanical performance, such as large deformation capacity and good energy absorption, and usually used as core material of sandwich panel, now it is widely used in automotive, aviation, aerospace and other fields, particularly suitable for various anti-collision structure and buffer structure. In this article, based on an engineering background, the INSTRON4505 electronic universal testing machine and split Hopkinson pressure bar (SHPB) were used for testing the static and dynamic mechanical properties of sandwich panel with different thickness steel plate- foam aluminum core, from the results we can see that the steel plate thickness has big influence on the stress-strain curve of the sandwich panel, and also takes the sandwich panel with 1mm steel panel to study the material strain rate dependence which under different high shock wave stress loaded, the results show that the sandwich panel is strain rate dependence material. And also, in order to get good waveforms in the SHPB experiment, the waveform shaped technique is used in the dynamic experiments, and the study of this paper will good to sandwich panel used in the engineering.

  20. The Comparison of Shear Bond Strength Between Fibre Reinforced Composite Posts with Three Different Composite Core Materials – An In vitro Study

    PubMed Central

    Anche, Sampath; Kakarla, Pranitha; Kadiyala, Krishna Kishore; Sreedevi, B.; Chiramana, Sandeep; Dev J., Ravi Rakesh; Manne, Sanjay Dutt; G., Deepthi

    2014-01-01

    Aim: The aim of this study is to compare the shear bond strength between fiber reinforced composite post with three different composite core materials. Materials and Methods: The materials used for the study were: 30 maxillary central incisors, pre fabricated fiber reinforced composite post (postec plus posts), Multi-core heavy body, Ti-core, Fluoro-core, Etchant gel, Silane coupling agent, Dentin bonding agent, Standardized gutta percha points, Rely-X dual cure composite resin. A total of 30 human maxillary central incisor were selected for this study. They were divided into three groups of 10 specimens each namely A, B and C. Results: The results obtained were analyzed by using one way analysis (ANOVA) and Tukey Honestly Significant Difference and they showed highest mean shear bond strength for group C when compared with group A and group B. There is no significant difference in the shear bond strength values between group A and group B. Conclusion: The teeth restored with multicore HB showed highest shear bond strength. The teeth restored with Fluoro core showed lowest shear bond strength. No statistically significant difference exists between the shear bond strength values between Ti-core and Fluoro-core. PMID:24596784

  1. Design Study for a Low-Enriched Uranium Core for the High Flux Isotope Reactor, Annual report for FY 2009

    SciTech Connect

    Chandler, David; Freels, James D; Ilas, Germina; Miller, James Henry; Primm, Trent; Sease, John D; Guida, Tracey; Jolly, Brian C

    2010-02-01

    This report documents progress made during FY 2009 in studies of converting the High Flux Isotope Reactor (HFIR) from high enriched uranium (HEU) fuel to low enriched uranium (LEU) fuel. Conversion from HEU to LEU will require a change in fuel form from uranium oxide to a uranium-molybdenum alloy. With axial and radial grading of the fuel foil and an increase in reactor power to 100 MW, calculations indicate that the HFIR can be operated with LEU fuel with no degradation in reactor performance from the current level. Results of selected benchmark studies imply that calculations of LEU performance are accurate. Studies are reported of the application of a silicon coating to surrogates for spheres of uranium-molybdenum alloy. A discussion of difficulties with preparing a fuel specification for the uranium-molybdenum alloy is provided. A description of the progress in developing a finite element thermal hydraulics model of the LEU core is provided.

  2. Tephrostratigraphic studies on a sediment core from Lake Prespa in the Balkans

    NASA Astrophysics Data System (ADS)

    Damaschke, M.; Sulpizio, R.; Zanchetta, G.; Wagner, B.; Böhm, A.; Nowaczyk, N.; Rethemeyer, J.; Hilgers, A.

    2013-01-01

    A detailed tephrostratigraphic record, which dates back to Marine Isotope Stage (MIS) 5b (ca. 91 kyr), has been established from a 17.76 m long core (Co1215) from Lake Prespa (Macedonia, Albania and Greece). A total of eleven tephra and cryptotephra layers (PT0915-1 to PT0915-11) were identified, using XRF scanning, magnetic susceptibility measurements, and macro- and microscopic inspection of the sediments. The major element composition of glass shards and/or micro-pumice fragments indicates that the tephras and cryptotephras originate from the explosive volcanism of Italy. Eight tephra and cryptotephra layers were correlated with specific volcanic eruptions: the AD 512 eruption of Somma-Vesuvius (1438 cal yr BP), the Mercato eruption of Somma-Vesuvius (8890 ± 90 cal yr BP), the Tufi Biancastri/LN1-LN2 eruption of the Campi Flegrei (14 749 ± 523 cal yr BP and 15 551 ± 621 cal yr BP), the SMP1-e/Y-3 eruption of the Campi Flegrei (30 000-31 000 cal yr BP), the Campanian Ignimbrite/Y-5 eruption of the Campi Flegrei (39 280 ± 110 cal yr BP), the SMP1-a event of Ischia Island (around 44 000 cal yr BP) and the Green Tuff/Y-6 eruption of Pantelleria Island (around 45 000 cal yr BP). One tephra could be attributed to the volcanic activity of Mount Etna, but probably represents an unknown eruption at ca. 60 000 cal yr BP. Cryptotephras PT0915-6 and PT0915-10 remain unclassified so far, but according to the presented age-depth model these would have been deposited around 35 000 and 48 500 cal yr BP, respectively. Some of the tephras and cryptotephras are recognised for the first time in the Balkan region. The tephrostratigraphic work provides important information about ash dispersal and explosion patterns of source volcanoes and can be used to correlate and date geographically distant paleoenvironmental and archaeological archives in the central Mediterranean region. Moreover, the tephrostratigraphic work in combination with radiocarbon and electron spin resonance (ESR

  3. Novel copper (Cu) loaded core-shell silica nanoparticles with improved Cu bioavailability: synthesis, characterization and study of antibacterial properties.

    PubMed

    Maniprasad, Pavithra; Santra, Swadeshmukul

    2012-08-01

    We report synthesis of a novel core-shell silica based antimicrobial nanoparticles where the silica shell has been engineered to accommodate copper (Cu). Synthesis of the core-shell Cu-silica nanoparticle (C-S CuSiO2NP) involves preparation of base-hydrolyzed Stöber silica "seed" particles first, followed by the acid-catalyzed seeded growth of the Cu-silica shell layer around the core. The Scanning Electron Microscopy (SEM) and the Transmission Electron Microscopy (TEM) measured the seed particle size to be -380 nm and the shell thickness to be -35 nm. The SEM particle characterization confirms formation of highly monodispersed particles with smooth surface morphology. Characterization of particle size distribution in solution by Dynamic Light Scattering (DLS) technique was fairly consistent with the electron microscopy results. Loading of Cu to nanoparticles was confirmed by the SEM-Energy Dispersive X-Ray Spectroscopy (EDS) and Atomic Absorption Spectroscopy (AAS). The Cu loading was estimated to be 0.098 microg of metallic copper per mg of C-S CuSiO2NP material by the AAS technique. Antibacterial efficacy of C-S CuSiO2NP was evaluated against E. coli and B. subtilis using Cu hydroxide ("Insoluble" Cu compound, sub-micron size particles) as positive control and silica "seed" particles (without Cu loading) as negative control. Bacterial growth in solution was measured against different concentrations of C-S CuSiO2NP to determine the Minimum Inhibitory Concentration (MIC) value. The estimated MIC values were 2.4 microg metallic Cu/mL for both E. coli and B. subtilis. Bac-light fluorescence microscopy based assay was used to count relative population of the live and dead bacteria cells. Antibacterial study clearly shows that C-S CuSiO2NP is more effective than insoluble Cu hydroxide particles at equivalent metallic Cu concentration, suggesting improvement of Cu bioavailability (i.e., more soluble Cu) in C-SCuSiO2NP material due to its core-shell design. PMID

  4. Childhood Trauma and Adult Interpersonal Functioning: A Study Using the Core Conflictual Relationship Theme Method (CCRT)

    ERIC Educational Resources Information Center

    Drapeau, M.; Perry, J.C.

    2004-01-01

    Objective: This study aimed to examine the long-term correlates of childhood trauma in regard to interpersonal functioning in adulthood. Method: One hundred and nineteen (N=119) subjects from the Austen Riggs Follow-along Study were included in the study. The Traumatic Antecedent Interview scoring method was used to assess 10 types of childhood…

  5. Challenges in Enacting Core Practices in Language Teacher Education: A Self-Study

    ERIC Educational Resources Information Center

    Peercy, Megan Madigan

    2014-01-01

    In this study, I explore my practices as a teacher educator in one course both before and after returning to the K-12 classroom to teach secondary language learners for one academic year. By examining the intersection of self-study and practice-based teacher education, I illustrate how I used self-study as a mechanism for innovation and change and…

  6. Labeling the oily core of nanocapsules and lipid-core nanocapsules with a triglyceride conjugated to a fluorescent dye as a strategy to particle tracking in biological studies.

    PubMed

    Fiel, Luana Almeida; Contri, Renata Vidor; Bica, Juliane Freitas; Figueiró, Fabrício; Battastini, Ana Maria Oliveira; Guterres, Sílvia Stanisçuaski; Pohlmann, Adriana Raffin

    2014-01-01

    The synthesis of novel fluorescent materials represents a very important step to obtain labeled nanoformulations in order to evaluate their biological behavior. The strategy of conjugating a fluorescent dye with triacylglycerol allows that either particles differing regarding supramolecular structure, i.e., nanoemulsions, nanocapsules, lipid-core nanocapsules, or surface charge, i.e., cationic nanocapsules and anionic nanocapsules, can be tracked using the same labeled material. In this way, a rhodamine B-conjugated triglyceride was obtained to prepare fluorescent polymeric nanocapsules. Different formulations were obtained, nanocapsules (NC) or lipid-core nanocapsules (LNC), using the labeled oil and Eudragit RS100, Eudragit S100, or poly(caprolactone) (PCL), respectively. The rhodamine B was coupled with the ricinolein by activating the carboxylic function using a carbodiimide derivative. Thin layer chromatography, proton nuclear magnetic resonance ((1)H-NMR), Fourier transform infrared spectroscopy (FTIR), UV-vis, and fluorescence spectroscopy were used to identify the new product. Fluorescent nanocapsule aqueous suspensions were prepared by the solvent displacement method. Their pH values were 4.6 (NC-RS100), 3.5 (NC-S100), and 5.0 (LNC-PCL). The volume-weighted mean diameter (D 4.3) and polydispersity values were 150 nm and 1.05 (NC-RS100), 350 nm and 2.28 (NC-S100), and 270 nm and 1.67 (LNC-PCL). The mean diameters determined by photon correlation spectroscopy (PCS) (z-average) were around 200 nm. The zeta potential values were +5.85 mV (NC-RS100), -21.12 mV (NC-S100), and -19.25 mV (LNC-PCL). The wavelengths of maximum fluorescence emission were 567 nm (NC-RS100 and LNC-PCL) and 574 nm (NC-S100). Fluorescence microscopy was used to evaluate the cell uptake (human macrophage cell line) of the fluorescent nanocapsules in order to show the applicability of the approach. When the cells were treated with the fluorescent nanocapsules, red emission was

  7. Labeling the oily core of nanocapsules and lipid-core nanocapsules with a triglyceride conjugated to a fluorescent dye as a strategy to particle tracking in biological studies

    NASA Astrophysics Data System (ADS)

    Fiel, Luana Almeida; Contri, Renata Vidor; Bica, Juliane Freitas; Figueiró, Fabrício; Battastini, Ana Maria Oliveira; Guterres, Sílvia Stanisçuaski; Pohlmann, Adriana Raffin

    2014-05-01

    The synthesis of novel fluorescent materials represents a very important step to obtain labeled nanoformulations in order to evaluate their biological behavior. The strategy of conjugating a fluorescent dye with triacylglycerol allows that either particles differing regarding supramolecular structure, i.e., nanoemulsions, nanocapsules, lipid-core nanocapsules, or surface charge, i.e., cationic nanocapsules and anionic nanocapsules, can be tracked using the same labeled material. In this way, a rhodamine B-conjugated triglyceride was obtained to prepare fluorescent polymeric nanocapsules. Different formulations were obtained, nanocapsules (NC) or lipid-core nanocapsules (LNC), using the labeled oil and Eudragit RS100, Eudragit S100, or poly(caprolactone) (PCL), respectively. The rhodamine B was coupled with the ricinolein by activating the carboxylic function using a carbodiimide derivative. Thin layer chromatography, proton nuclear magnetic resonance (1H-NMR), Fourier transform infrared spectroscopy (FTIR), UV-vis, and fluorescence spectroscopy were used to identify the new product. Fluorescent nanocapsule aqueous suspensions were prepared by the solvent displacement method. Their pH values were 4.6 (NC-RS100), 3.5 (NC-S100), and 5.0 (LNC-PCL). The volume-weighted mean diameter ( D 4.3) and polydispersity values were 150 nm and 1.05 (NC-RS100), 350 nm and 2.28 (NC-S100), and 270 nm and 1.67 (LNC-PCL). The mean diameters determined by photon correlation spectroscopy (PCS) ( z-average) were around 200 nm. The zeta potential values were +5.85 mV (NC-RS100), -21.12 mV (NC-S100), and -19.25 mV (LNC-PCL). The wavelengths of maximum fluorescence emission were 567 nm (NC-RS100 and LNC-PCL) and 574 nm (NC-S100). Fluorescence microscopy was used to evaluate the cell uptake (human macrophage cell line) of the fluorescent nanocapsules in order to show the applicability of the approach. When the cells were treated with the fluorescent nanocapsules, red emission was detected

  8. Vibrational spectra study of fluorescent dendrimers built from the cyclotriphosphazene core with terminal dansyl and carbamate groups

    NASA Astrophysics Data System (ADS)

    Furer, V. L.; Vandyukova, I. I.; Vandyukov, A. E.; Fuchs, S.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

    2011-08-01

    The FTIR and FT Raman spectra of the "Janus"-type dendrimers, possessing five carbamate groups on one side and five fluorescent dansyl derivatives on the other side, with amide G1 and hydrazone G2 central linkages were studied. These surface-block dendrimers are obtained by the coupling of two different dendrons. The FTIR and FT-Raman spectra of the zero generation dendrons, built from the hexafunctional cyclotriphosphazene core, with five dansyl terminal groups and one carbamate G0 v and one oxybenzaldehyde function G0v have been recorded. The structural optimization and normal mode analysis were performed for dendron G0v on the basis of the density functional theory (DFT). The calculated geometrical parameters and harmonic vibrational frequencies are predicted in a good agreement with the experimental data. It was found that dendron molecule G0v has a concave lens structure with planar -O-C6H4-CHdbnd O fragments and slightly non-planar cyclotriphosphazene core. The experimental IR and Raman spectra of dendron G0v were interpreted by means of potential energy distributions. Relying on DFT calculations a complete vibrational assignment is proposed. The strong band 1597 cm -1 show marked changes of the optical density in dependence of substituents in the aromatic ring. The frequencies of ν(N-H) bands in the IR spectra reveal the presence of the different types of H-bonds in the dendrimers.

  9. Characteristic of core materials in polymeric micelles effect on their micellar properties studied by experimental and dpd simulation methods.

    PubMed

    Cheng, Furong; Guan, Xuewa; Cao, Huan; Su, Ting; Cao, Jun; Chen, Yuanwei; Cai, Mengtan; He, Bin; Gu, Zhongwei; Luo, Xianglin

    2015-08-15

    Polymeric micelles are one important class of nanoparticles for anticancer drug delivery, but the impact of hydrophobic segments on drug encapsulation and release is unclear, which deters the rationalization of drug encapsulation into polymeric micelles. This paper focused on studying the correlation between the characteristics of hydrophobic segments and encapsulation of structurally different drugs (DOX and β-carotene). Poly(ϵ-caprolactone) (PCL) or poly(l-lactide) (PLLA) were used as hydrophobic segments to synthesize micelle-forming amphiphilic block copolymers with the hydrophilic methoxy-poly(ethylene glycol) (mPEG). Both blank and drug loaded micelles were spherical in shape with sizes lower than 50 nm. PCL-based micelles exhibited higher drug loading capacity than their PLLA-based counterparts. Higher encapsulation efficiency of β-carotene was achieved compared with DOX. In addition, both doxorubicin and β-carotene were released much faster from PCL-based polymeric micelles. Dissipative particle dynamics (DPD) simulation revealed that the two drugs tended to aggregate in the core of the PCL-based micelles but disperse in the core of PLLA based micelles. In vitro cytotoxicity investigation of DOX loaded micelles demonstrated that a faster drug release warranted a more efficient cancer-killing effect. This research could serve as a guideline for the rational design of polymeric micelles for drug delivery. PMID:26196277

  10. A study on the measurement of the core body temperature change after radiofrequency ablation (RFA) through MR temperature mapping

    NASA Astrophysics Data System (ADS)

    Kim, Chang-Bok; Dong, Kyung-Rae; Yu, Young; Chung, Woon-Kwan; Cho, Jae-Hwan; Joo, Kyu-Ji

    2013-09-01

    This study examined the change in the heat generated during radiofrequency ablation (RFA) using a self-manufactured phantom and used magnetic resonance imaging (MRI) to analyze the change in the temperature of the core body and the tissues surrounding the phantom. In this experiment, the image and the phase image were obtained simultaneously from a gradient echo-based sequence using 1.5-Tesla MRI equipment and a 12-channel head coil. The temperature mapping technique was used to calculate the change in temperature. The regions of interest (ROIs) (ROI 1 - ROI 6) were set with a focus on the area where the RFA was performed, according to the temperature distribution, before monitoring the temperature change for one hour in time intervals of five minutes. The results showed that the temperature change in the ROI with time was largest in the ROI 1 and smallest in the ROI 5. In addition, after the RFA procedure, the temperature decreased from the initial value to 0 °C in one hour. The temperature changes in the core body and the surrounding tissues were confirmed by MRI temperature mapping, which is a noninvasive method.

  11. Theoretical studies on the interactions of XIAP-BIR3 domain with bicyclic and tricyclic core monovalent Smac mimetics.

    PubMed

    Ling, Baoping; Dong, Lihua; Zhang, Rui; Wang, Zhiguo; Liu, Yongjun; Liu, Chengbu

    2010-11-01

    X-linked IAP can bind caspase-9 and inhibit its activity. Mitochondrial protein Smac/DIABLO can also interact with XIAP and relieve the inhibition on caspase-9 to induce apoptosis. A series of artificial Smac mimetics have been used to mimic the Smac N-terminal tetrapeptide AVPI to bind to XIAP-BIR3, but these structural diverse mimetics exhibited distinct binding affinities. To get an insight into the binding nature and optimize the structures, molecular docking and dynamics simulations were used to study the binding of XIAP-BIR3 with three groups of Smac mimetics. The docking results reveal that these Smac mimetics anchored on the surface groove of XIAP-BIR3 and superimposed well with AVPI. The modifications on the seven-membered ring of bicyclic core segment do not strengthen the binding affinity, while a benzyl introduced to the five-membered ring is favorable to the binding. Molecular dynamics simulations on three typical systems show that these complexes are very stable. Hydrogen bonds between the bicyclic core segment and Thr308 play critical roles in maintaining the stability of complex. The binding free energies calculated by MM_PBSA method are consistent with the experimental results. PMID:20980180

  12. Occupied and unoccupied electronic structures of an L-cysteine film studied by core-absorption and resonant photoelectron spectroscopies

    NASA Astrophysics Data System (ADS)

    Kamada, M.; Hideshima, T.; Azuma, J.; Yamamoto, I.; Imamura, M.; Takahashi, K.

    2016-04-01

    Unoccupied and occupied electronic structures of an L-cysteine film have been studied by absorption and resonant photoelectron spectroscopies. Core absorptions at S-L, C-K, N-K, and O-K levels indicate that the lower unoccupied states are predominantly composed of oxygen-2p, carbon-2p, and sulfur-4s+3d orbitals, while higher unoccupied states may be attributed dominantly to nitrogen-np (n ≥ 3), oxygen-np (n ≥ 3), and sulfur-ns+md (n ≥ 4, m ≥ 3) orbitals. Resonant photoelectron spectra at S-L23 and O-K levels indicate that the highest occupied state is originated from sulfur-3sp orbitals, while oxygen-2sp orbitals contribute to the deeper valence states. The delocalization lifetimes of the oxygen-1s and sulfur-2p excited states are estimated from a core-hole clock method to be about 9 ± 1 and 125 ± 25 fs, respectively.

  13. Application of Core Dynamics Modeling to Core-Mantle Interactions

    NASA Technical Reports Server (NTRS)

    Kuang, Weijia

    2003-01-01

    Observations have demonstrated that length of day (LOD) variation on decadal time scales results from exchange of axial angular momentum between the solid mantle and the core. There are in general four core-mantle interaction mechanisms that couple the core and the mantle. Of which, three have been suggested likely the dominant coupling mechanism for the decadal core-mantle angular momentum exchange, namely, gravitational core-mantle coupling arising from density anomalies in the mantle and in the core (including the inner core), the electromagnetic coupling arising from Lorentz force in the electrically conducting lower mantle (e.g. D-layer), and the topographic coupling arising from non-hydrostatic pressure acting on the core-mantle boundary (CMB) topography. In the past decades, most effort has been on estimating the coupling torques from surface geomagnetic observations (kinematic approach), which has provided insights on the core dynamical processes. In the meantime, it also creates questions and concerns on approximations in the studies that may invalidate the corresponding conclusions. The most serious problem is perhaps the approximations that are inconsistent with dynamical processes in the core, such as inconsistencies between the core surface flow beneath the CMB and the CMB topography, and that between the D-layer electric conductivity and the approximations on toroidal field at the CMB. These inconsistencies can only be addressed with numerical core dynamics modeling. In the past few years, we applied our MoSST (Modular, Scalable, Self-consistent and Three-dimensional) core dynamics model to study core-mantle interactions together with geodynamo simulation, aiming at assessing the effect of the dynamical inconsistencies in the kinematic studies on core-mantle coupling torques. We focus on topographic and electromagnetic core-mantle couplings and find that, for the topographic coupling, the consistency between the core flow and the CMB topography is

  14. Structural study of a bent-core liquid crystal showing the B{sub 1}-B{sub 2} transition

    SciTech Connect

    Folcia, Cesar Luis; Etxebarria, J.; Ortega, J.; Ros, M. B.

    2006-09-15

    An experimental study of the B{sub 1}-B{sub 2} transition is carried out in a bent-core liquid crystal. The study is essentially based on x-ray measurements as a function of temperature. The B{sub 1}-B{sub 2} transition is extremely unusual and implies a deep structural change from a columnar phase to a lamellar phase. We have found that the B{sub 1} phase in our compound is similar to the so-called B{sub 1} reversed phase, with an additional splay of the polarization in the columns. On approaching the B{sub 2} phase the width of the cross section of the columns increases. The transition is clearly first order, with a large hysteresis though the enthalpy content is very small. A possible mechanism for the transition is briefly sketched.

  15. Formation of core-shell Au@Ag nanorods induced by catecholamines: A comparative study and an analytical application.

    PubMed

    Gorbunova, M V; Apyari, V V; Dmitrienko, S G; Garshev, A V

    2016-09-14

    Gold nanorods (AuNRs) stabilized by cetyltrimethylammonium bromide (CTAB) were synthesized and an interaction of catecholamines (CAs) with silver ions in the presence of the obtained AuNRs was studied. The reaction results into formation of core-shell Au@Ag nanorods (Au@AgNRs) and leads to a hypsochromic shift of the long-wave surface plasmon resonance (SPR) band in the absorption spectrum of AuNRs. The influence of a CA structure, excess of CTAB, interaction time, pH, concentration of AuNRs, silver ions and CAs on this interaction was studied. Based on correlation of the NRs spectral characteristics with the concentration of CAs, a method for spectrophotometric determination of dobutamine, epinephrine, norepinephrine and dopamine with detection limits 27, 18, 16 and 13 μg L(-1), respectively, has been developed. The method can be applied to the analysis of medicines. PMID:27566354

  16. Independent studies using deep sequencing resolve the same set of core bacterial species dominating gut communities of honey bees.

    PubMed

    Sabree, Zakee L; Hansen, Allison K; Moran, Nancy A

    2012-01-01

    Starting in 2003, numerous studies using culture-independent methodologies to characterize the gut microbiota of honey bees have retrieved a consistent and distinctive set of eight bacterial species, based on near identity of the 16S rRNA gene sequences. A recent study [Mattila HR, Rios D, Walker-Sperling VE, Roeselers G, Newton ILG (2012) Characterization of the active microbiotas associated with honey bees reveals healthier and broader communities when colonies are genetically diverse. PLoS ONE 7(3): e32962], using pyrosequencing of the V1-V2 hypervariable region of the 16S rRNA gene, reported finding entirely novel bacterial species in honey bee guts, and used taxonomic assignments from these reads to predict metabolic activities based on known metabolisms of cultivable species. To better understand this discrepancy, we analyzed the Mattila et al. pyrotag dataset. In contrast to the conclusions of Mattila et al., we found that the large majority of pyrotag sequences belonged to clusters for which representative sequences were identical to sequences from previously identified core species of the bee microbiota. On average, they represent 95% of the bacteria in each worker bee in the Mattila et al. dataset, a slightly lower value than that found in other studies. Some colonies contain small proportions of other bacteria, mostly species of Enterobacteriaceae. Reanalysis of the Mattila et al. dataset also did not support a relationship between abundances of Bifidobacterium and of putative pathogens or a significant difference in gut communities between colonies from queens that were singly or multiply mated. Additionally, consistent with previous studies, the dataset supports the occurrence of considerable strain variation within core species, even within single colonies. The roles of these bacteria within bees, or the implications of the strain variation, are not yet clear. PMID:22829932

  17. Independent Studies Using Deep Sequencing Resolve the Same Set of Core Bacterial Species Dominating Gut Communities of Honey Bees

    PubMed Central

    Sabree, Zakee L.; Hansen, Allison K.; Moran, Nancy A.

    2012-01-01

    Starting in 2003, numerous studies using culture-independent methodologies to characterize the gut microbiota of honey bees have retrieved a consistent and distinctive set of eight bacterial species, based on near identity of the 16S rRNA gene sequences. A recent study [Mattila HR, Rios D, Walker-Sperling VE, Roeselers G, Newton ILG (2012) Characterization of the active microbiotas associated with honey bees reveals healthier and broader communities when colonies are genetically diverse. PLoS ONE 7(3): e32962], using pyrosequencing of the V1–V2 hypervariable region of the 16S rRNA gene, reported finding entirely novel bacterial species in honey bee guts, and used taxonomic assignments from these reads to predict metabolic activities based on known metabolisms of cultivable species. To better understand this discrepancy, we analyzed the Mattila et al. pyrotag dataset. In contrast to the conclusions of Mattila et al., we found that the large majority of pyrotag sequences belonged to clusters for which representative sequences were identical to sequences from previously identified core species of the bee microbiota. On average, they represent 95% of the bacteria in each worker bee in the Mattila et al. dataset, a slightly lower value than that found in other studies. Some colonies contain small proportions of other bacteria, mostly species of Enterobacteriaceae. Reanalysis of the Mattila et al. dataset also did not support a relationship between abundances of Bifidobacterium and of putative pathogens or a significant difference in gut communities between colonies from queens that were singly or multiply mated. Additionally, consistent with previous studies, the dataset supports the occurrence of considerable strain variation within core species, even within single colonies. The roles of these bacteria within bees, or the implications of the strain variation, are not yet clear. PMID:22829932

  18. A Value-Added Study of Teacher Spillover Effects across Four Core Subjects in Middle Schools

    ERIC Educational Resources Information Center

    Yuan, Kun

    2015-01-01

    This study examined the existence, magnitude, and impact of teacher spillover effects (TSEs) across teachers of four subject areas (i.e., mathematics, English language arts [ELA], science, and social studies) on student achievement in each of the four subjects at the middle school level. The author conducted a series of value-added (VA) analyses,…

  19. Evaluation of Core Vocabulary Intervention for Treatment of Inconsistent Phonological Disorder: Three Treatment Case Studies

    ERIC Educational Resources Information Center

    McIntosh, Beth; Dodd, Barbara

    2009-01-01

    Children with unintelligible speech differ in severity, underlying deficit, type of surface error patterns and response to treatment. Detailed treatment case studies, evaluating specific intervention protocols for particular diagnostic groups, can identify best practice for children with speech disorder. Three treatment case studies evaluated the…

  20. Evaluation of Core Vocabulary Intervention for Treatment of Inconsistent Phonological Disorder: Three Treatment Case Studies

    ERIC Educational Resources Information Center

    McIntosh, Beth; Dodd, Barbara

    2008-01-01

    Children with unintelligible speech differ in severity, underlying deficit, type of surface error patterns and response to treatment. Detailed treatment case studies, evaluating specific intervention protocols for particular diagnostic groups, can identify best practice for children with speech disorder. Three treatment case studies evaluated the…

  1. A Unit of Study Approach for Teaching Common Core State Standards for Writing

    ERIC Educational Resources Information Center

    Pytash, Kristine E.; Morgan, Denise N.

    2013-01-01

    In this article, the authors provide an overview of the unit of study framework for teaching writing and explain how it sets the stage for developing "academic momentum" in students (Strahan, 2008, p. 4). To help readers understand the unit of study framework in action, the authors describe how a unit unfolds in one subject area,…

  2. Getting at the Core of Literacy Improvement: A Case Study of an Urban Secondary School

    ERIC Educational Resources Information Center

    Francois, Chantal

    2014-01-01

    Although national trends of urban adolescent reading underachievement suggest that schools are unable to adequately support this population's reading development, some studies have demonstrated that urban schools can operate to raise student achievement, thereby disrupting national trends. In this study, the author investigates one such…

  3. Influence of dimensionality and interface type on optical and electronic properties of CdS/ZnS core-shell nanocrystals—A first-principles study

    NASA Astrophysics Data System (ADS)

    Kocevski, V.; Eriksson, O.; Gerard, C.; Sarma, D. D.; Rusz, J.

    2015-10-01

    Semiconducting nanocrystals (NCs) have become one of the leading materials in a variety of applications, mainly due to their size tunable band gap and high intensity emission. Their photoluminescence (PL) properties can be notably improved by capping the nanocrystals with a shell of another semiconductor, making core-shell structures. We focus our study on the CdS/ZnS core-shell nanocrystals that are closely related to extensively studied CdSe/CdS NCs, albeit exhibiting rather different photoluminescence properties. We employ density functional theory to investigate the changes in the electronic and optical properties of these nanocrystals with size, core/shell ratio, and interface structure between the core and the shell. We have found that both the lowest unoccupied eigenstate (LUES) and the highest occupied eigenstate (HOES) wavefunction (WF) are localized in the core of the NCs, with the distribution of the LUES WF being more sensitive to the size and the core/shell ratio. We show that the radiative lifetimes are increasing, and the Coulomb interaction energies decrease with increasing NC size. Furthermore, we investigated the electronic and optical properties of the NCs with different interfaces between the core and the shell and different core types. We find that the different interfaces and core types have rather small influence on the band gaps and the absorption indexes, as well as on the confinement of the HOES and LUES WFs. Also the radiative lifetimes are found to be only slightly influenced by the different structural models. In addition, we compare these results with the previous results for CdSe/CdS NCs, reflecting the different PL properties of these two types of NCs. We argue that the difference in their Coulomb interaction energies is one of the main reasons for their distinct PL properties.

  4. Neogene deformation in the West Antarctic Rift in the McMurdo Sound region from studies of the ANDRILL and Cape Roberts drill cores

    NASA Astrophysics Data System (ADS)

    Paulsen, T. S.; Wilson, T. J.; Jarrard, R. D.; Millan, C.; Saddler, D.; Läufer, A.; Pierdominici, S.

    2010-12-01

    Seismic studies indicate that the West Antarctic rift system records at least two distinct periods of Cenozoic rifting (Paleogene and Neogene) within the western Ross Sea. Natural fracture data from ANDRILL and Cape Roberts drill cores are revealing a picture of the geodynamic patterns associated with these rifting episodes. Kinematic indicators along faults recovered in drill cores document dominant normal faulting, although reverse and strike-slip faults are also present. Ongoing studies of mechanically twinned calcite in veins recovered in the drill cores yield predominantly vertical shortening strains with horizontal extension, consistent with a normal fault regime. In the Cape Roberts Project drill core, faults of inferred Oligocene age document a dominant NNE maximum horizontal stress associated with Paleogene rifting within the Victoria Land Basin. The NNE maximum horizontal stress at Cape Roberts is at an oblique angle to Transantarctic Mountain front, and consistent with previous interpretations invoking Cenozoic dextral transtensional shear along the boundary. In the ANDRILL SMS (AND-2A) drill core, faults and veins presumably associated with Neogene rifting document a dominant NNW to NE faulting of an expanded Lower Miocene section, although subsidiary WNW faulting is also present within the upper sections of oriented core. In the ANDRILL MIS (AND-1B) drill core, natural fractures are consistently present through the core below c. 450 mbsf, the estimated depth of the ‘B-clino’ seismic reflector. This is consistent with the presence of seismically-detectable faults below this horizon, which record the major faulting episode associated with Neogene rifting in the Terror Rift. Sedimentary intrusions and steep veins folded by compaction indicate that deformation occurred prior to complete lithification of the strata, suggesting that deformation was at least in part coeval with deposition. Faults and associated veins intersected in the AND-1B drill core

  5. Influence of dimensionality and interface type on optical and electronic properties of CdS/ZnS core-shell nanocrystals—A first-principles study

    SciTech Connect

    Kocevski, V. E-mail: vancho.kocevski@physics.uu.se; Eriksson, O.; Gerard, C.; Rusz, J.; Sarma, D. D.

    2015-10-28

    Semiconducting nanocrystals (NCs) have become one of the leading materials in a variety of applications, mainly due to their size tunable band gap and high intensity emission. Their photoluminescence (PL) properties can be notably improved by capping the nanocrystals with a shell of another semiconductor, making core-shell structures. We focus our study on the CdS/ZnS core-shell nanocrystals that are closely related to extensively studied CdSe/CdS NCs, albeit exhibiting rather different photoluminescence properties. We employ density functional theory to investigate the changes in the electronic and optical properties of these nanocrystals with size, core/shell ratio, and interface structure between the core and the shell. We have found that both the lowest unoccupied eigenstate (LUES) and the highest occupied eigenstate (HOES) wavefunction (WF) are localized in the core of the NCs, with the distribution of the LUES WF being more sensitive to the size and the core/shell ratio. We show that the radiative lifetimes are increasing, and the Coulomb interaction energies decrease with increasing NC size. Furthermore, we investigated the electronic and optical properties of the NCs with different interfaces between the core and the shell and different core types. We find that the different interfaces and core types have rather small influence on the band gaps and the absorption indexes, as well as on the confinement of the HOES and LUES WFs. Also the radiative lifetimes are found to be only slightly influenced by the different structural models. In addition, we compare these results with the previous results for CdSe/CdS NCs, reflecting the different PL properties of these two types of NCs. We argue that the difference in their Coulomb interaction energies is one of the main reasons for their distinct PL properties.

  6. Stable-isotope studies on ice cores and snow pits in Dronning Maud Land, Antarctica, covering the past 2000 years

    NASA Astrophysics Data System (ADS)

    Oerter, H.; Kipfstuhl, S.; Wilhelms, F.

    2012-12-01

    During the past 15 years various ice cores were drilled at and upstream of Kohnen station (75.0017 S, 0.0678 E, 2882 m a.s.l.) Dronning Maud Land, East Antarctica, supplemented by snow pit studies. These data sets of stable-isotope data (18O, D, deuterium excess d) are available over various time periods displaying centennial and strong decadal variations. 5 ice cores are used to create staked profiles of the deviation of the 18O content from the mean of the period 1259-1816 (an interval well defined by 2 unique volcanic events) for the time slices of the past 2000 and 200 years. For the past 50 years data from various shallow firn cores and snow pits in the area will be presented. The used reference period for the short term studies is 1961-1990. δ18O values may be converted to temperature with the local gradient of 0.77 δ18O-‰/°C. The Common Era follows the Roman period which is characterised by isotope values or temperatures, respectively, higher than observed in the 2000 years afterwards until today. The so-called medieval optimum around 1050-1250 is recognisable. The so-called Little Ice Age, which is attributed to the period 1650-1850 in the Northern hemisphere, is not clearly displayed. Overall, a slight cooling (0.008 δ18O-‰/100a) is evident within the Common Era until 1900. In the time slice of the past 200 years the coldest period occurred between 1875 and 1900. During the 20th century the isotope content and thus the air temperature have been increasing (0.88 δ18O-‰/100a) and reached values in the first decade of the 21st century clearly higher than around 1800 and before. The 1940ies formed the coldest decade in the 20th century, another relative minimum appeared in the 1980ies. The time series with shallow firn cores and snow pits stop at 2008 CE. For the past 50 years it is not possible to determine a trend unambiguously. This is due to the decadal variations and the shortness of the time series from single pits and shallow cores. However

  7. Palaeoclimatic changes during the Upper Cretaceous of eastern Denmark: a study based on the Stevns-2 chalk core

    NASA Astrophysics Data System (ADS)

    Boussaha, M.; Stemmerik, L.; Thibault, N.

    2013-12-01

    Cretaceous Danish Basin (Surlyk and Lykke-Andersen, 2007). Acknowledgments: Funding for this study was provided by Maersk Oil, the Danish Natural Science Research Foundation and the University of Copenhagen. REFERENCES Stemmerik, L., Surlyk, F., Klitten, K., Rasmussen, S. L., Schovsbo, N., 2006. Shallow core drilling of the Upper Cretaceous Chalk at Stevns Klint, Denmark. GEUS, 2006. Geological Survey of Denmark and Greenland Bulletin 10, 13-16. Surlyk, F., Lykker-Andersen, H., 2007. Contourite drifts, moats and channels in the Upper Cretaceous chalk of the Danish Basin. Sedimentology 54, 405-42. Thibault, N., & Gardin, S., 2006. Maastrichtian calcareous nannofossil biostratigraphy and paleoecology in the Equatorial Atlantic (Demerara Rise, ODP Leg 207 Hole 1258A). Revue de micropaléontologie 49, 199-214. Thibault, N., Schovsbo, N., Harlou, R., Stemmerik, L., Surlyk, F., 2011. An age-calibrated record of upper Campanian - Maastrichtian climate change in the Boreal Realm. AGU Fall meeting 2011, San Francisco, USA, 05-12-11.

  8. An In Vitro Study on the Effects of Post-Core Design and Ferrule on the Fracture Resistance of Endodontically Treated Maxillary Central Incisors

    PubMed Central

    Sreedevi, S; Sanjeev, R; Raghavan, Rekha; Abraham, Anna; Rajamani, T; Govind, Girish Kumar

    2015-01-01

    Background: Endodontically treated teeth have significantly different physical and mechanical properties compared to vital teeth and are more prone to fracture. The study aims to compare the fracture resistance of endodontically treated teeth with and without post reinforcement, custom cast post-core and prefabricated post with glass ionomer core and to evaluate the ferrule effect on endodontically treated teeth restored with custom cast post-core. Materials and Methods: A total of 40 human maxillary central incisors with similar dimensions devoid of any root caries, restorations, previous endodontic treatment or cracks were selected from a collection of stored extracted teeth. An initial silicone index of each tooth was made. They were treated endodontically and divided into four groups of ten specimens each. Their apical seal was maintained with 4 mm of gutta-percha. Root canal preparation was done and then post core fabrication was done. The prepared specimens were subjected to load testing using a computer coordinated UTM. The fracture load results were then statistically analyzed. One-way ANOVA was followed by paired t-test. Results: 1. Reinforcement of endodontically treated maxillary central incisors with post and core, improved their fracture resistance to be at par with that of endodontically treated maxillary central incisor, with natural crown. 2. The fracture resistance of endodontically treated maxillary central incisors is significantly increased when restored with custom cast post-core and 2 mm ferrule. Conclusion: With 2 mm ferrule, teeth restored with custom cast post-core had a significantly higher fracture resistance than teeth restored with custom cast post-core or prefabricated post and glass ionomer core without ferrule. PMID:26464537

  9. Prospective Study for Comparison of Endoscopic Ultrasound-Guided Tissue Acquisition Using 25- and 22-Gauge Core Biopsy Needles in Solid Pancreatic Masses

    PubMed Central

    Lee, Sang Hoon; Lee, Hee Seung; Lee, Hyun Jik; Park, Jeong Yup; Park, Seung Woo; Song, Si Young; Kim, Hoguen; Chung, Jae Bock; Bang, Seungmin

    2016-01-01

    Background and Aims Although thicker needles theoretically allow more tissue to be collected, their decreased flexibility can cause mechanical damage to the endoscope, technical failure, and sample blood contamination. The effects of needle gauge on diagnostic outcomes of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) of pancreatic mass lesions remain unknown. This study compared procurement rates of histologic cores obtained from EUS-FNB of pancreatic masses using 25- and 22-gauge core biopsy needles. Patients and Methods From March 2014 to July 2014, 66 patients with solid pancreatic mass underwent EUS-FNB with both 25- and 22-gauge core biopsy needles. Among them, 10 patients were excluded and thus 56 patients were eligible for the analyses. Needle sequences were randomly assigned, and two passes were made with each needle, consisting of 10 uniform to-and-fro movements on each pass with 10 mL syringe suction. A pathologist blinded to needle sequence evaluated specimens for the presence of histologic core. Results The mean patient age was 65.8 ± 9.5 years (range, 44–89 years); 35 patients (62.5%) were men. The mean pancreatic mass size was 35.3 ± 17.1 mm (range 14–122.3 mm). Twenty-eight patients (50%) had tumors at the pancreas head or uncinate process. There were no significant differences in procurement rates of histologic cores between 25-gauge (49/56, 87.5%) and 22-gauge (46/56, 82.1%, P = 0.581) needles or diagnostic accuracy using only histologic cores (98% and 95%). There were no technical failures or procedure-related adverse events. Conclusions The 25-gauge core biopsy needle could offer acceptable and comparable outcomes regarding diagnostic performance including histologic core procurement rates compared to the 22-gauge core biopsy needle, although the differences were not statistically significant. Trial Registration ClinicalTrials.gov NCT01795066 PMID:27149404

  10. Scoping studies of the alternative options for defueling, packaging, shipping, and disposing of the TMI-2 spent fuel core

    SciTech Connect

    Anderson, Robert T.

    1980-09-01

    A portion of this fuel will be shipped to nuclear facilities to perform detailed physical examinations. Removal of this fuel from the TMI-2 core is also a significant step in the eventual cleanup of this facility. The report presents a scoping study of the technical operations required for defueling and canning. The TMI fuel when canned could be stored in the spent fuel storage pool. After a period of on-site storage, it is expected that the bulk of the fuel will be shipped off-site for either storage or reprocessing. Evaluation is made of the technical, economic, and institutional factors associated with alternate approaches to disposition of this fuel. Recommendations are presented concerning future generic development tasks needed for the defueling, packaging, on-site shipping of this fuel.

  11. Strain localization in granodiorite mylonites: a microstructural and electron backscatter diffraction (EBSD) study of the South Mountains core complex, Arizona

    NASA Astrophysics Data System (ADS)

    Greenberg, R. M.; Miranda, E.

    2009-12-01

    The quantification of strain localization in detachment fault shear zones is essential to the study of continental core complex development and permits insight into continental crust rheology during extension. We present a microstructural and EBSD study of naturally deformed shear zone rocks from the footwall of the South Mountains, Arizona, core complex to interpret the deformation mechanisms that lead to strain localization along the detachment fault. The footwall of the South Mountains core complex is dominated by a Miocene composite pluton that exhibits Miocene extensional mylonitic fabrics associated with the structural development of the core complex. The composite pluton is composed of granodiorite, granite, and quartzolite, but the granodiorite is the most voluminous of the intrusive units. The detachment fault shear zone is developed within the granodiorite and quartzolite intrusive units. We conducted a microstructural and EBSD study of the Tertiary South Mountains granodiorite and quartzolite mylonites to determine the deformation mechanisms that promote strain localization. We hypothesize that the strength of quartz strongly influences strain localization in the naturally deformed granodiorite mylonites and quartzolite mylonites. The five samples were collected on an up-structure traverse through the ~60 meter thick mylonitic shear zone towards the interpreted detachment fault surface. Microstructural observation of quartz grains reveals the presence of elongate ‘ribbon grains’ with subgrain development along the rims of these grains, and irregular and sinuous sutured grain boundaries. We interpret these microstructures as evidence of Regimes 2 and 3 dynamic recrystallization. In contrast, the plagioclase feldspar and potassium feldspar crystals are microfractured with limited development of bulging grain boundaries on the rims of the feldspar grains, which we interpret as evidence of Regime 1 dynamic recrystallization. Up the traverse in the

  12. Polarization study on solid core photonic crystal fibers partially sedimented with polyethylene micro-spheres and carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Pérez-Chimal, R. Janette; Mata-Chávez, Ruth I.; Estudillo-Ayala, J. M.; Vargas-Rodríguez, E.; Alvarado-Méndez, E.; Rojas-Laguna, R.

    2010-10-01

    We present an experimental study of light polarization on solid core microstructured optical fibers type (Large Mode Area) LMA-16, LMA-20 and LMA-25. These fibers were partially filled with one micron diameter polyethylene spheres or carbon nanotubes diluted in distilled H2O by capillarity. Polarization characterization was realized on these Photonic Crystal fibers with air filled holes and partially particle filled holes using a He-Ne 633nm central wavelength laser at 10mW. The achieved results were compared using graphical data of every test collected at different exposition dates where the fiber was exposed to particle sedimentation. Results depicted that short time sedimentation of these particles does not change the light polarization leaving from the fiber except for the phase of the beam. On the other hand, longer time particle exposition visibly changes the light phase measured at the end of the photonic crystal fiber with repeatable results.

  13. Synthesis and optical study of green light emitting polymer coated CdSe/ZnSe core/shell nanocrystals

    SciTech Connect

    Tripathi, S.K.; Sharma, Mamta

    2013-05-15

    Highlights: ► Synthesis of Polymer coated core CdSe and CdSe/ZnSe core/shell NCs. ► From TEM image, the spherical nature of CdSe and CdSe/ZnSe is obtained. ► Exhibiting green band photoemission peak at 541 nm and 549 nm for CdSe core and CdSe/ZnSe core/shell NCs. ► The shell thickness has been calculated by using superposition of quantum confinement energy model. - Abstract: CdSe/ZnSe Core/Shell NCs dispersed in PVA are synthesized by chemical method at room temperature. This is characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV/Vis spectra and photoluminescence spectroscopy (PL). TEM image shows the spherical nature of CdSe/ZnSe core/shell NCs. The red shift of absorption and emission peak of CdSe/ZnSe core/shell NCs as compared to CdSe core confirmed the formation of core/shell. The superposition of quantum confinement energy model is used for calculation of thickness of ZnSe shell.

  14. Clearing the Highest Hurdle: Human-Based Case Studies Broaden Students' Knowledge of Core Evolutionary Concepts

    ERIC Educational Resources Information Center

    Werth, Alexander J.

    2009-01-01

    An anonymous survey instrument was used for a ten year study to gauge college student attitudes toward evolution. Results indicate that students are most likely to accept evolution as a historical process for change in physical features of non-human organisms. They are less likely to accept evolution as an ongoing process that shapes all traits…

  15. The Special Education Core Curriculum Manual: Competency Level -- Communication Skills, Mathematics, Life Skills, and Study Skills.

    ERIC Educational Resources Information Center

    Margolis, Leonard; And Others

    The manual is intended to provide basic objectives and teaching strategies for teachers of handicapped children at the upper elementary and secondary level in the areas of communication, mathematics, life skills, and study skills. Each subject area is divided into sub-sections under which learning objectives and associated teaching activities are…

  16. The Development of Core Cognitive Skills in Autism: A 3-Year Prospective Study

    ERIC Educational Resources Information Center

    Pellicano, Elizabeth

    2010-01-01

    This longitudinal study tested the veracity of one candidate multiple-deficits account of autism by assessing 37 children with autism (M age = 67.9 months) and 31 typical children (M age = 65.2 months) on tasks tapping components of theory of mind (ToM), executive function (EF), and central coherence (CC) at intake and again 3 years later. As a…

  17. Re-Establishing Social Studies as a Core Subject: An Interview with Susan Griffin

    ERIC Educational Resources Information Center

    Griffin, Susan

    2014-01-01

    NCSS Executive Director Susan Griffin was chair of the Task Force of Professional Organizations that worked with the Social Studies Assessment, Curriculum, and Instruction Collaborative (SSACI) of the Council of Chief State School Officers to initiate and guide the development of the "College, Career and Civic Life (C3) Framework for Social…

  18. Student Presentations of Case Studies to Illustrate Core Concepts in Soil Biogeochemistry

    ERIC Educational Resources Information Center

    Duckworth, Owen W.; Harrington, James M.

    2012-01-01

    Soil biogeochemistry, a discipline that explores the chemical speciation and transformations of elements in soils and the relationships between soils and global biogeochemical cycles, is becoming a popular course offering because it unites themes from a number of other courses. In this article, we present a set of case studies that have been used…

  19. Putting History at the Core: History and Literature in Environmental Studies

    ERIC Educational Resources Information Center

    Morse, Kathryn

    2003-01-01

    When environmental studies programs broaden their curricular offerings into the humanities, their first stop is often environmental literature, particularly classics such as Henry David Thoreau's "Walden," Aldo Leopold's "A Sand County Almanac," and Rachel Carson's "Silent Spring." Environmental literature courses consider many of the works of…

  20. THE INNER CORE--NORTH, A STUDY OF MILWAUKEE'S NEGRO COMMUNITY.

    ERIC Educational Resources Information Center

    O'REILLY, CHARLES T.

    A STUDY OF THE NEGRO COMMUNITY OF MILWAUKEE PRESENTS DATA ON RESIDENCE, EDUCATION, HOUSING, OCCUPATIONS AND EMPLOYMENT, THE EMERGING MIDDLE CLASS, AND PROGNOSTICATIONS ABOUT THE FUTURE GROWTH OF NEGRO POPULATION. MOST OF THE AVAILABLE INFORMATION WAS DERIVED FROM THE 1960 CENSUS, WITH COMPARISONS CONTINUALLY MADE TO THE 1950 CENSUS FIGURES. AN…

  1. A Study of the Access to the Scholarly Record From a Hospital Health Science Core Collection.

    ERIC Educational Resources Information Center

    Williams, James F., II; Pings, Vern M.

    This study is an effort to determine possible service performance levels in hospital libraries, based on access to the scholarly record of medicine through selected lists of clinical journals and indexing and abstracting journals. Specific emphasis is placed on (1) the citation verification through the use of the index and abstract journals, (2)…

  2. Improving Middle School Parental Engagement in Transition to Common Core State Standards: An Action Research Study

    ERIC Educational Resources Information Center

    Harla, Donna K.

    2014-01-01

    Parental involvement in schools is an important potential contributor to improving American education and making the U.S. more globally competitive. This qualitative and quantitative mixed-methodology action research study probed the viability of engaging parents around issues of educational improvement by inviting them to participate in training…

  3. Study of drip-line nuclei with a core plus multi-valence nucleon model

    NASA Astrophysics Data System (ADS)

    Masui, H.; Myo, T.; Katō, K.; Ikeda, K.

    2005-09-01

    We study neutron- and proton-rich nuclei with an extended cluster-orbital shell model (COSM) approach, which we call Neo-COSM. The binding energies and r.m.s. radii of oxygen isotopes are reproduced. For N = 8 isotones, the tendency of the abrupt increase of the r.m.s. radii is qualitatively improved.

  4. Sexual behaviour among young Danes aged 15–29 years: a cross-sectional study of core indicators

    PubMed Central

    Jørgensen, Marianne Johansson; Maindal, Helle Terkildsen; Christensen, Kaj Sparle; Olesen, Frede; Andersen, Berit

    2015-01-01

    Objectives Sexually transmitted infections and unwanted pregnancies occur at high rates among youth. Understanding sexual behaviour is essential for planning and implementing future effective preventive interventions. The present study examines the sexual behaviour in the general Danish population aged 15–29 years using the core indicators recommended by the European Centre for Disease Prevention and Control. Methods A nationwide cross-sectional study was conducted in Denmark among a random sample of 20 000 men and women in 2012. Respondents completed a web-based sexual behaviour questionnaire and data were linked to a nationally held demographic database. Core indicators for sexual behaviour frequency stratified by gender are presented as unweighted and weighted data after consideration of sociodemographic differences between respondents and non-respondents. Results Response rate was 20.4%. Condoms were used at sexual debut by 69.9% of women and 62.3% of men, while 14.3% of women and 15.1% of men used no contraceptives at sexual debut. Half of the respondents used condom alone at the latest sexual encounter with a steady partner (women 51.8%, men 55.2%), while 10% used no contraceptives. Having a sexual encounter with a casual partner decreased the likelihood of using condoms (women 43.7%, men 49.5%) and increased the likelihood of using no contraceptives (women 14.8%, men 20.9%). Data on sexual behaviour characteristics showed only minor changes when weighted for non-response. Conclusions The findings call for interventions addressing the use of appropriate contraception at sexual debut and at last sexual encounter; this seems particularly important when the sexual partner is a casual partner. PMID:25609258

  5. Core components of clinical education: a qualitative study with attending physicians and their residents

    PubMed Central

    ESTEGHAMATI, ALIREZA; BARADARAN, HAMIDREZA; MONAJEMI, ALIREZA; KHANKEH, HAMID REZA; GERANMAYEH, MEHRNAZ

    2016-01-01

    Introduction In medical education, particularly in residency courses, most of the training occurs in real clinical environments. Workplace-based learning profoundly affects students’ knowledge, attitudes, and practice; therefore, it should be properly planned.  Due to the extensiveness   of the clinical   environment   and   its   importance in training residents, investigating how residents learn in these environments and detecting factors that influence effectiveness will help curriculum designers to promote residents’ learning by improving their learning environment.  Therefore, our qualitative content analysis study, aimed  to  examine  the experiences and perspectives of internal and surgical residents and their attending physicians about learning in clinical settings. Methods This qualitative content analysis study was conducted through purposeful sampling.  Semi-structured interviews were conducted with 15 internal and surgical residents and 15 of their attending physicians at educational hospitals of Tehran University of Medical Sciences. Results The main categories explored in this study were hidden curriculum, learning resources, and learning conditions. In the context of clinical environment and under its individual culture, residents learn professionalism and learn to improve their communication skills with patients and colleagues. Because of clinical obligations such as priority of treating the patients for education or workload of the attending physicians, residents acquire most of their practical knowledge from colleagues, fellows, or follow-up patients in different learning conditions (such as: educational rounds, morning reports and outpatient clinics). They see some of their attending physicians as role models. Conclusion Changing cultural and contextual factors is of prime importance to promote a learning-oriented environment in a clinical setting. The present findings will help curriculum planners and attending physicians to

  6. Multiple Core Galaxies

    NASA Technical Reports Server (NTRS)

    Miller, R.H.; Morrison, David (Technical Monitor)

    1994-01-01

    Nuclei of galaxies often show complicated density structures and perplexing kinematic signatures. In the past we have reported numerical experiments indicating a natural tendency for galaxies to show nuclei offset with respect to nearby isophotes and for the nucleus to have a radial velocity different from the galaxy's systemic velocity. Other experiments show normal mode oscillations in galaxies with large amplitudes. These oscillations do not damp appreciably over a Hubble time. The common thread running through all these is that galaxies often show evidence of ringing, bouncing, or sloshing around in unexpected ways, even though they have not been disturbed by any external event. Recent observational evidence shows yet another phenomenon indicating the dynamical complexity of central regions of galaxies: multiple cores (M31, Markarian 315 and 463 for example). These systems can hardly be static. We noted long-lived multiple core systems in galaxies in numerical experiments some years ago, and we have more recently followed up with a series of experiments on multiple core galaxies, starting with two cores. The relevant parameters are the energy in the orbiting clumps, their relative.masses, the (local) strength of the potential well representing the parent galaxy, and the number of cores. We have studied the dependence of the merger rates and the nature of the final merger product on these parameters. Individual cores survive much longer in stronger background potentials. Cores can survive for a substantial fraction of a Hubble time if they travel on reasonable orbits.

  7. A harmonised approach for identifying core foods for total diet studies.

    PubMed

    Devlin, Niamh F C; McNulty, Breige A; Turrini, Aida; Tlustos, Christina; Hearty, Aine P; Volatier, Jean-Luc; Kelleher, Cecily C; Nugent, Anne P

    2014-01-01

    Total diet studies (TDS) are used to gather information on chemical substances in food, thereby facilitating risk assessments and health monitoring. Candidate foods for inclusion in a TDS should represent a large part of a typical diet to estimate accurately the exposure of a population and/or specific population groups. There are currently no harmonised guidelines for the selection of foods in a TDS, and so the aim of this study was to explore the possibility of generating a harmonised approach to be used across Europe. Summary statistics data from the European Food Safety Authority's (EFSA) Comprehensive Food Consumption Database were used in this research, which provided data from national food consumption surveys in Europe. The chosen methodology for the selection of foods was based on the weight of food consumed and consumer rate. Using the available data, 59 TDS food lists were created, representing over 51 000 people across 17 countries and seven population groups. All TDS food lists represented > 85% of the populations' diets (85.9-96.3%), while the number of foods in the TDS food lists ranged from 15 to 102. Comparison of the TDS food lists indicated that the most commonly consumed foods included wheat bread and rolls, pastries and cakes, tomatoes, apples, bananas, and chicken, while cow's milk, tap water and orange juice were the most commonly consumed beverages across Europe. This work was complete to support EFSA and other institutions in the development of harmonised TDS into the future. PMID:24893144

  8. Revisit of polystyrene-modified fullerene core stars: A computational study.

    PubMed

    Zhou, Jia

    2015-09-01

    Density functional theory (DFT) calculations have been used to clarify the number of poly(styryl) lithium anions that are grafted onto C60 fullerene. The computational results suggest that 6-arm-grafted C60 fullerene is the most thermodynamically favorable, and the grafted C60 fullerene with arms more than 6 is only achievable under certain circumstances. This observation is consistent with the previous experiments [Macromolecules 2013; 46:7451-57.]. Both electronic effect and steric effect have been thoroughly examined and they are found to play different roles in the arm-grafted C60 fullerene. The current study will pave a way for the future architecture of polymers on C60 fullerene and the like. PMID:26188799

  9. Developing the new Columbia core curriculum: a case study in managing radical curriculum change.

    PubMed

    Galea, Sandro; Fried, Linda P; Walker, Julia R; Rudenstine, Sasha; Glover, Jim W; Begg, Melissa D

    2015-03-01

    Curricular change is essential for maintaining vibrant, timely, and relevant educational programming. However, major renewal of a long-standing curriculum at an established university presents many challenges for leaders, faculty, staff, and students. We present a case study of a dramatic curriculum renewal of one of the nation's largest Master of Public Health degree programs: Columbia University's Mailman School of Public Health. We discuss context, motivation for change, the administrative structure established to support the process, data sources to inform our steps, the project timeline, methods for engaging the school community, and the extensive planning that was devoted to evaluation and communication efforts. We highlight key features that we believe are essential for successful curricular change. PMID:25706010

  10. Molecular dynamics study of the aqueous core of a reversed ionic micelle

    NASA Astrophysics Data System (ADS)

    Linse, Per

    1989-05-01

    The molecular structure and dynamics of a molecular electric double layer have been examined with the molecular dynamics simulation technique. A 50 ps trajectory from a simulation of a model system comprising 50 sodium ions and 1000 water molecules, spherically enclosed by a hydrophobic interface carrying 50 carboxylate groups, has been analyzed. The results show that the water structure is strongly distorted by the strong local fields and that the hydrophobic interface plays only a secondary role. The orientational polarization of the interfacial water molecules has been examined and compared with dielectric continuum theory. The dynamical results of this study show a reduced rate of translational as well as rotational motions of ionic hydrating water by a factor of 2-4 as compared to bulk water.

  11. Gyrokinetic studies of core turbulence features in ASDEX Upgrade H-mode plasmas

    SciTech Connect

    Navarro, A. Bañón Told, D.; Happel, T.; Görler, T.; Abiteboul, J.; Bustos, A.; Doerk, H.; Jenko, F.

    2015-04-15

    Gyrokinetic validation studies are crucial for developing confidence in the model incorporated in numerical simulations and thus improving their predictive capabilities. As one step in this direction, we simulate an ASDEX Upgrade discharge with the GENE code, and analyze various fluctuating quantities and compare them to experimental measurements. The approach taken is the following. First, linear simulations are performed in order to determine the turbulence regime. Second, the heat fluxes in nonlinear simulations are matched to experimental fluxes by varying the logarithmic ion temperature gradient within the expected experimental error bars. Finally, the dependence of various quantities with respect to the ion temperature gradient is analyzed in detail. It is found that density and temperature fluctuations can vary significantly with small changes in this parameter, thus making comparisons with experiments very sensitive to uncertainties in the experimental profiles. However, cross-phases are more robust, indicating that they are better observables for comparisons between gyrokinetic simulations and experimental measurements.

  12. Micro coring apparatus

    NASA Technical Reports Server (NTRS)

    Collins, David; Brooks, Marshall; Chen, Paul; Dwelle, Paul; Fischer, Ben

    1989-01-01

    A micro-coring apparatus for lunar exploration applications, that is compatible with the other components of the Walking Mobile Platform, was designed. The primary purpose of core sampling is to gain an understanding of the geological composition and properties of the prescribed environment. This procedure has been used extensively for Earth studies and in limited applications during lunar explorations. The corer is described and analyzed for effectiveness.

  13. Operative Technique and Clinical Outcome in Endoscopic Core Decompression of Osteochondral Lesions of the Talus: A Pilot Study

    PubMed Central

    Beck, Sascha; Claßen, Tim; Haversath, Marcel; Jäger, Marcus; Landgraeber, Stefan

    2016-01-01

    Background Revitalizing the necrotic subchondral bone and preserving the intact cartilage layer by retrograde drilling is the preferred option for treatment of undetached osteochondral lesions of the talus (OLT). We assessed the effectiveness of Endoscopic Core Decompression (ECD) in treatment of OLT. Material/Methods Seven patients with an undetached OLT of the medial talar dome underwent surgical treatment using an arthroscopically-guided transtalar drill meatus for core decompression of the lesion. Under endoscopic visualization the OLT was completely debrided while preserving the cartilage layer covering the defect. The drill tunnel and debrided OLT were filled using an injectable bone graft substitute. Various clinical scores, radiographic imaging, and MRI were evaluated after a mean follow-up of 24.1 months. Results The American Orthopedic Foot and Ankle Society Score significantly improved from 71.0±2.4 to 90.3±5.9, and the Foot and Ankle Disability Index improved from 71.8±11.1 to 91.7±4.8. Radiographically, we observed good bone remodelling of the medial talar dome contour within 3 months. In MRI, an alteration of the bony signal of the drill tunnel and the excised OLT remained for more than 12 months. Conclusions First follow-up results for the surgical technique described in this study are highly promising for treatment of undetached stable OLT grade II or transitional stage II–III according to the Pritsch classification. Even lesions larger than 150 mm2 showed good clinical scores, with full restoration of the medial talar dome contour in radiographic imaging. PMID:27362485

  14. Operative Technique and Clinical Outcome in Endoscopic Core Decompression of Osteochondral Lesions of the Talus: A Pilot Study.

    PubMed

    Beck, Sascha; Claßen, Tim; Haversath, Marcel; Jäger, Marcus; Landgraeber, Stefan

    2016-01-01

    BACKGROUND Revitalizing the necrotic subchondral bone and preserving the intact cartilage layer by retrograde drilling is the preferred option for treatment of undetached osteochondral lesions of the talus (OLT). We assessed the effectiveness of Endoscopic Core Decompression (ECD) in treatment of OLT. MATERIAL AND METHODS Seven patients with an undetached OLT of the medial talar dome underwent surgical treatment using an arthroscopically-guided transtalar drill meatus for core decompression of the lesion. Under endoscopic visualization the OLT was completely debrided while preserving the cartilage layer covering the defect. The drill tunnel and debrided OLT were filled using an injectable bone graft substitute. Various clinical scores, radiographic imaging, and MRI were evaluated after a mean follow-up of 24.1 months. RESULTS The American Orthopedic Foot and Ankle Society Score significantly improved from 71.0±2.4 to 90.3±5.9, and the Foot and Ankle Disability Index improved from 71.8±11.1 to 91.7±4.8. Radiographically, we observed good bone remodelling of the medial talar dome contour within 3 months. In MRI, an alteration of the bony signal of the drill tunnel and the excised OLT remained for more than 12 months. CONCLUSIONS First follow-up results for the surgical technique described in this study are highly promising for treatment of undetached stable OLT grade II or transitional stage II-III according to the Pritsch classification. Even lesions larger than 150 mm2 showed good clinical scores, with full restoration of the medial talar dome contour in radiographic imaging. PMID:27362485

  15. The relationship between Obsessive-Compulsive symptoms and PARKIN genotype: The CORE-PD study

    PubMed Central

    Sharp, ME; Caccappolo, E; Mejia-Santana, H; Tang, M–X; Rosado, L; Orbe Reilly, M; Ruiz, D; Louis, ED; Comella, C; Nance, M; Bressman, S; Scott, WK; Tanner, C; Waters, C; Fahn, S; Cote, L; Ford, B; Rezak, M; Novak, K; Friedman, JH; Pfeiffer, R; Payami, H; Molho, E; Factor, SA; Nutt, J; Serrano, C; Arroyo, M; Pauciulo, MW; Nichols, WC; Clark, LN; Alcalay, RN; Marder, KS

    2014-01-01

    Background Few studies have systematically investigated the association between PARKIN genotype and psychiatric co-morbidities of PD. PARKIN-associated PD is characterized by severe nigral dopaminergic neuronal loss, a finding that may have implications for behaviors rooted in dopaminergic circuits such as obsessive-compulsive symptoms (OCS). Methods The Schedule of Compulsions and Obsessions Patient Inventory (SCOPI) was administered to 104 patients with early-onset PD and 257 asymptomatic first-degree relatives. Carriers of one and two PARKIN mutations were compared to non-carriers. Results Among patients, carriers scored lower than non-carriers in adjusted models (one-mutation: 13.9 point difference, p=0.03; two-mutation: 24.1, p=0.001), where lower scores indicate less OCS. Among asymptomatic relatives, there was a trend towards the opposite: mutation carriers scored higher than non-carriers (one mutation p = 0.05; two mutations p = 0.13). Conclusions First, there was a significant association between PARKIN mutation status and obsessive-compulsive symptom level in both PD and asymptomatics, suggesting that OCS might represent an early non-motor dopamine-dependent feature. Second, irrespective of disease status, heterozygotes were significantly different that non-carriers suggesting that PARKIN heterozygosity may contribute to phenotype. PMID:25393808

  16. Cannibalism Affects Core Metabolic Processes in Helicoverpa armigera Larvae-A 2D NMR Metabolomics Study.

    PubMed

    Vergara, Fredd; Shino, Amiu; Kikuchi, Jun

    2016-01-01

    Cannibalism is known in many insect species, yet its impact on insect metabolism has not been investigated in detail. This study assessed the effects of cannibalism on the metabolism of fourth-instar larvae of the non-predatory insect Helicoverpa armigera (Lepidotera: Noctuidea). Two groups of larvae were analyzed: one group fed with fourth-instar larvae of H. armigera (cannibal), the other group fed with an artificial plant diet. Water-soluble small organic compounds present in the larvae were analyzed using two-dimensional nuclear magnetic resonance (NMR) and principal component analysis (PCA). Cannibalism negatively affected larval growth. PCA of NMR spectra showed that the metabolic profiles of cannibal and herbivore larvae were statistically different with monomeric sugars, fatty acid- and amino acid-related metabolites as the most variable compounds. Quantitation of ¹H-(13)C HSQC (Heteronuclear Single Quantum Coherence) signals revealed that the concentrations of glucose, glucono-1,5-lactone, glycerol phosphate, glutamine, glycine, leucine, isoleucine, lysine, ornithine, proline, threonine and valine were higher in the herbivore larvae. PMID:27598144

  17. Study of coordination environments around Pd and Pt in a Pd-core Pt-shell nanoparticle during heating

    NASA Astrophysics Data System (ADS)

    Nishimura, Y. F.; Hamaguchi, T.; Yamaguchi, S.; Takagi, H.; Dohmae, K.; Nonaka, T.; Nagai, Y.

    2016-05-01

    Local coordination environments around Pd and Pt in a Pd-core Pt-shell nanoparticle (NP) at temperatures ranging from 473 to 873 K was evaluated by utilizing in situ XAFS measurement technique to investigate the temperature range in which a core-shell structure is preserved. The core-shell structure was considered to be kept up to 673 K and start to change at about 773 K. Heating to 873 K accelerated atomic mixing in the core-shell NPs. Catalytic properties of the present Pd-core Pt-shell NP are available in the stoichiometric C3H6-O2 atmosphere at temperatures less than 773 K at most.

  18. Support for the Core Research Activities and Studies of the Computer Science and Telecommunications Board (CSTB)

    SciTech Connect

    Jon Eisenberg, Director, CSTB

    2008-05-13

    The Computer Science and Telecommunications Board of the National Research Council considers technical and policy issues pertaining to computer science (CS), telecommunications, and information technology (IT). The functions of the board include: (1) monitoring and promoting the health of the CS, IT, and telecommunications fields, including attention as appropriate to issues of human resources and funding levels and program structures for research; (2) initiating studies involving CS, IT, and telecommunications as critical resources and sources of national economic strength; (3) responding to requests from the government, non-profit organizations, and private industry for expert advice on CS, IT, and telecommunications issues; and to requests from the government for expert advice on computer and telecommunications systems planning, utilization, and modernization; (4) fostering interaction among CS, IT, and telecommunications researchers and practitioners, and with other disciplines; and providing a base of expertise in the National Research Council in the areas of CS, IT, and telecommunications. This award has supported the overall operation of CSTB. Reports resulting from the Board's efforts have been widely disseminated in both electronic and print form, and all CSTB reports are available at its World Wide Web home page at cstb.org. The following reports, resulting from projects that were separately funded by a wide array of sponsors, were completed and released during the award period: 2007: * Summary of a Workshop on Software-Intensive Systems and Uncertainty at Scale * Social Security Administration Electronic Service Provision: A Strategic Assessment * Toward a Safer and More Secure Cyberspace * Software for Dependable Systems: Sufficient Evidence? * Engaging Privacy and Information Technology in a Digital Age * Improving Disaster Management: The Role of IT in Mitigation, Preparedness, Response, and Recovery 2006: * Renewing U.S. Telecommunications Research

  19. Core-level photoabsorption study of defects and metastable bonding configurations in boron nitride

    SciTech Connect

    Jimenez, I.; Jankowski, A.F.; Terminello, L.J.

    1997-04-01

    Boron nitride is an interesting material for technological applications and for fundamental solid state physics investigations. It is a compound isoelectronic with carbon and, like carbon can possess sp{sup 2} and sp{sup 3} bonded phases resembling graphite and diamond. BN crystallizes in the sp{sup 2}-bonded hexagonal (h-BN), rhombohedral (r-BN) and turbostratic phases, and in the sp{sup 3}-bonded cubic (c-BN) and wurtzite (w-BN) phases. A new family of materials is obtained when replacing C-C pairs in graphite with isoelectronic B-N pairs, resulting in C{sub 2}BN compounds. Regarding other boron compounds, BN is exceptional in the sense that it has standard two-center bonds with conventional coordination numbers, while other boron compounds (e.g. B{sub 4}C) are based on the boron icosahedron unit with three-center bonds and high coordination numbers. The existence of several allotropic forms and fullerene-like structures for BN suggests a rich variety of local bonding and poses the questions of how this affects the local electronic structure and how the material accommodates the stress induced in the transition regions between different phases. One would expect point defects to play a crucial role in stress accommodation, but these must also have a strong influence in the electronic structure, since the B-N bond is polar and a point defect will thus be a charged structure. The study of point defects in relationship to the electronic structure is of fundamental interest in these materials. Recently, the authors have shown that Near-Edge X-ray Absorption Fine Structure (NEXAFS) is sensitive to point defects in h-BN, and to the formation of metastable phases even in amorphous materials. This is significant since other phase identification techniques like vibrational spectroscopies or x-ray diffraction yield ambiguous results for nanocrystalline and amorphous samples. Serendipitously, NEXAFS also combines chemical selectivity with point defect sensitivity.

  20. Core Decompression and Autologous Bone Marrow Concentrate for Treatment of Femoral Head Osteonecrosis: A Randomized Prospective Study

    PubMed Central

    Pepke, Wojciech; Kasten, Philip; Beckmann, Nicholas A.; Janicki, Patricia; Egermann, Marcus

    2016-01-01

    The aim of this study was to investigate the safety of injection of bone marrow aspirate concentrate during core decompression and to study its clinical (visual analogue scale; Harris-Hip-score) and radiological outcomes (magnetic resonance imaging). In this prospective and randomized clinical trial we evaluated 24 consecutive patients with non-traumatic femoral head necrosis (FHN) during a period of two years after intervention. In vitro analysis of mesenchymal stem cells was performed by evaluating the fibroblast colony forming units (CFU-Fs). Postoperatively, significant decrease in pain associated with a functional benefit lasting was observed. However, there was no difference in the clinical outcome between the two study groups. Over the period of two years there was no significant difference between the head survival rate between both groups. In contrast to that, we could not perceive any significant change in the volume of FHN in both treatment groups related to the longitudinal course after treating. The number of CFU showed a significant increase after centrifugation. This trial could not detect a benefit from the additional injection of bone marrow concentrate with regard to bone regeneration and clinical outcome in the short term. PMID:27114808

  1. Core Decompression and Autologous Bone Marrow Concentrate for Treatment of Femoral Head Osteonecrosis: A Randomized Prospective Study.

    PubMed

    Pepke, Wojciech; Kasten, Philip; Beckmann, Nicholas A; Janicki, Patricia; Egermann, Marcus

    2016-03-21

    The aim of this study was to investigate the safety of injection of bone marrow aspirate concentrate during core decompression and to study its clinical (visual analogue scale; Harris-Hip-score) and radiological outcomes (magnetic resonance imaging). In this prospective and randomized clinical trial we evaluated 24 consecutive patients with non-traumatic femoral head necrosis (FHN) during a period of two years after intervention. In vitro analysis of mesenchymal stem cells was performed by evaluating the fibroblast colony forming units (CFU-Fs). Postoperatively, significant decrease in pain associated with a functional benefit lasting was observed. However, there was no difference in the clinical outcome between the two study groups. Over the period of two years there was no significant difference between the head survival rate between both groups. In contrast to that, we could not perceive any significant change in the volume of FHN in both treatment groups related to the longitudinal course after treating. The number of CFU showed a significant increase after centrifugation. This trial could not detect a benefit from the additional injection of bone marrow concentrate with regard to bone regeneration and clinical outcome in the short term. PMID:27114808

  2. A copper-based intrauterine device with gold or platinum core: in vitro and in vivo studies.

    PubMed

    Gonen, R; Gal-Or, L; Zilberman, A; Scharf, M

    1981-12-01

    The use of copper intrauterine contraceptive devices is currently limited to 2-3 years, mainly due to wire fragmentation, which was observed as early as after 8 months of use. In the resulting search for a long-lasting device, two new systems of duplex wire, with gold and platinum cores electrolytically coated with copper, were devised and studied. Initially, duplex wires and controls were exposed to physiological solution. Copper dissolution rate, and corrosion morphology were studied by weight-loss measurements and optical metallography. Similar systems were then surgically implanted in rat uteri for varying periods up to 26 weeks. Electron microanalysis of corrosion products in addition to weight-loss measurements and metallography was performed. The results showed that a uniform and ductile copper coating is obtainable by electroplating on gold and platinum wires. The rate of copper dissolution is similar to that of solid copper wire. No dissolution of gold and platinum in the controls or coated wires was detected by weight loss, metallography or atomic absorption measurements. Microanalysis of the deposits and corrosion products on the wires in the uterine environment showed the presence of compounds containing sulphur, chlorine, calcium and copper. The results of this study suggest that supplementing IUDs with copper-coated gold or platinum wires may result in significant prolongation of the life-span of the device by preventing uncontrolled loss of copper caused by wire fragmentation. PMID:7326937

  3. Ten-Year Results From the Natrelle 410 Anatomical Form-Stable Silicone Breast Implant Core Study

    PubMed Central

    Maxwell, G. Patrick; Van Natta, Bruce W.; Bengtson, Bradley P.; Murphy, Diane K.

    2015-01-01

    Background Silicone breast implants have long been used for breast augmentation and reconstruction. During this time, these medical devices have gone through a number of modifications to improve their safety, quality, and clinical outcome performance. Objectives The authors conducted a 10-year study to determine the safety and effectiveness of Natrelle 410 silicone breast implants. Methods This prospective, multicenter study enrolled 941 subjects who were undergoing either augmentation, augmentation revision, reconstruction, or reconstruction revision. Data on complications, reoperations, explantations, and subject satisfaction were collected at annual clinic visits, and one-third of subjects underwent biennial magnetic resonance imaging (MRI) to screen for implant rupture. The authors used the Kaplan-Meier estimator to calculate risk rates for local complications, reoperations, and explantations. Results Capsular contracture rates increased approximately 1% per year from the previously reported 6-year rates. The rates were significantly lower than those from the Natrelle round gel core study. The overall rate of confirmed ruptured implants in subjects who underwent MRI was 5.7%. Eleven late seromas were reported. The most common reason for explantation was a subject requesting a size or style change. Satisfaction rates remained high through 10 years, with most subjects saying they were somewhat or definitely satisfied with their implants. Conclusions This 10-year prospective trial demonstrated the long-term safety and effectiveness of Natrelle 410 anatomical form-stable implants. The complication rates were low and the satisfaction rates were high. Level of Evidence: 1 Therapeutic PMID:25717116

  4. Magnetorotational iron core collapse

    NASA Technical Reports Server (NTRS)

    Symbalisty, E. M. D.

    1984-01-01

    During its final evolutionary stages, a massive star, as considered in current astrophysical theory, undergoes rapid collapse, thereby triggering a sequence of a catastrophic event which results in a Type II supernova explosion. A remnant neutron star or a black hole is left after the explosion. Stellar collapse occurs, when thermonuclear fusion has consumed the lighter elements present. At this stage, the core consists of iron. Difficulties arise regarding an appropriate model with respect to the core collapse. The present investigation is concerned with the evolution of a Type II supernova core including the effects of rotation and magnetic fields. A simple neutrino model is developed which reproduced the spherically symmetric results of Bowers and Wilson (1982). Several two-dimensional computational models of stellar collapse are studied, taking into account a case in which a 15 solar masses iron core was artificially given rotational and magnetic energy.

  5. Different Timing Features in Brain Processing of Core and Moral Disgust Pictures: An Event-Related Potentials Study

    PubMed Central

    Zhang, Youxue; Lou, Liandi; Ding, Daoqun

    2015-01-01

    Disgust, an emotion motivating withdrawal from offensive stimuli, protects us from the risk of biological pathogens and sociomoral violations. Homogeneity of its two types, namely, core and moral disgust has been under intensive debate. To examine the dynamic relationship between them, we recorded event-related potentials (ERPs) for core disgust, moral disgust and neutral pictures while participants performed a modified oddball task. ERP analysis revealed that N1 and P2 amplitudes were largest for the core disgust pictures, indicating automatic processing of the core disgust-evoking pictures. N2 amplitudes were higher for pictures evoking moral disgust relative to core disgust and neutral pictures, reflecting a violation of social norms. The core disgust pictures elicited larger P3 and late positive potential (LPP) amplitudes in comparison with the moral disgust pictures which, in turn, elicited larger P3 and LPP amplitudes when compared to the neutral pictures. Taken together, these findings indicated that core and moral disgust pictures elicited different neural activities at various stages of information processing, which provided supporting evidence for the heterogeneity of disgust. PMID:26011635

  6. Depositional and surface exposure history of the Shorty Crater core 74001/2 - FMR and magnetic studies

    NASA Technical Reports Server (NTRS)

    Morris, R. V.; Gose, W. A.; Lauer, H. V., Jr.

    1978-01-01

    Surface exposure (maturity) indices and concentrations of FeO and metallic iron were determined at 0.5-cm intervals of the Apollo 17 core section, which sampled a pyroclastic deposit on the rim of Shorty Crater. The determinations showed that all of the soil in the core is extremely immature. An exposure history of the core is proposed: accumulation (about 3.6 billion years ago), shallow burial (during the first 20 million years), deep burial (till about 10-15 million years ago), followed by excavation (10-15 million years ago), and in situ reworking (till the present).

  7. Automated tru-cut imaging-guided core needle biopsy of canine orbital neoplasia. A prospective feasibility study

    PubMed Central

    Cirla, A.; Rondena, M.; Bertolini, G.

    2016-01-01

    The purpose of this study was to evaluate the diagnostic value of imaging-guided core needle biopsy for canine orbital mass diagnosis. A second excisional biopsy obtained during surgery or necropsy was used as the reference standard. A prospective feasibility study was conducted in 23 canine orbital masses at a single centre. A complete ophthalmic examination was always followed by orbital ultrasound and computed tomography (CT) examination of the head. All masses were sampled with the patient still on the CT table using ultrasound (US) guided automatic tru-cut device. The most suitable sampling approach to the orbit was chosen each time based on the CT image analysis. One of the following different approaches was used: trans-orbital, trans-conjunctival or trans-masseteric. In all cases, the imaging-guided biopsy provided a sufficient amount of tissue for the histopathological diagnosis, which concurred with the biopsies obtained using the excisional technique. CT examination was essential for morphological diagnosis and provided detailed topographic information that allowed us to choose the safest orbital approach for the biopsy. US guided automatic tru-cut biopsy based on CT images, performed with patient still on the CT table, resulted in a minimally invasive, relatively easy, and accurate diagnostic procedure in dogs with orbital masses. PMID:27540512

  8. HPC-enabled Nuclear Structure Studies - Description and Applications of the Symmetry-adapted No-Core Shell Model

    NASA Astrophysics Data System (ADS)

    Draayer, J. P.; Dytrych, T.; Launey, K. D.; Dreyfuss, A. C.; Langr, D.

    2015-02-01

    By exploiting symmetries that enable the accounting of vital collective correlations in nuclei, we achieve significantly reduced dimensions for equivalent ultra-large model spaces, and hence resolve the scale explosion problem in nuclear structure calculations, i.e, the explosive growth in computational resource demands with increasing number of particles and size of the spaces in which they reside. As a result, we provide - with the help of High Performance Computing (HPC) resources - first solutions for selected benchmark calculations with remarkable findings of large-deformation and low-spin dominance in low-lying nuclear states. In the framework of a complementary symmetry-adapted study, one is able, facilitated by symmetry-preserving pieces of the inter-nucleon interaction, to accommodate unprecedented shell-model spaces critical to capture the physics governing the Hoyle state in 12C, thereby addressing a 60-year-old puzzle on the emergence of cluster substructures within a no-core shell model framework. All of these findings underline the key role of symmetries in nuclear structure studies.

  9. High Temperature Corrosion and Characterization Studies in Flux Cored Arc Welded 2.25Cr-1Mo Power Plant Steel

    NASA Astrophysics Data System (ADS)

    Kumaresh Babu, S. P.; Natarajan, S.

    2010-07-01

    Higher productivity is registered with Flux cored arc welding (FCAW) process in many applications. Further, it combines the characteristics of shielded metal arc welding (SMAW), gas metal arc welding (GMAW), and submerged arc welding (SAW) processes. This article describes the experimental work carried out to evaluate and compare corrosion and its inhibition in SA 387 Gr.22 (2.25Cr-1Mo) steel weldments prepared by FCAW process with four different heat inputs exposed to hydrochloric acid medium at 0.1, 0.5, and 1.0 M concentrations. The parent metal, weld metal, and heat-affected zone are chosen as regions of exposure for the study carried out at 100 °C. Electrochemical polarization techniques such as Tafel line extrapolation (Tafel) and linear polarization resistance (LPR) have been used to measure the corrosion current. The role of hexamine and mixed inhibitor (thiourea + hexamine in 0.5 M HCl), each at 100 ppm concentration is studied in these experiments. Microstructural observation, hardness survey, surface characterization, and morphology using scanning electron microscope (SEM) and x-ray diffraction (XRD) have been made on samples to highlight the nature and extent of film formation. The film is found to contain Fe2Si, FeSi2, FeMn3, Fe7Mo3, Fe3O4, FeO, FeCr, AlO7Fe3SiO3, and KFe4Mn77Si19.

  10. Study on size effect of the silica nanospheres with solid core and mesoporous shell on cellular uptake.

    PubMed

    Peruzynska, M; Cendrowski, K; Barylak, M; Roginska, D; Tarnowski, M; Tkacz, M; Kurzawski, M; Machalinski, B; Mijowska, E; Drozdzik, M

    2015-12-01

    The properties of mesoporous silica nanoparticles including large surface area, large pore volume, easy surface functionalization and control of structure and pore size has made them promising drug carriers. In this study, the effect of different diameters (50 nm, 70 nm, 90 nm, 110 nm and 140 nm) of silica nanospheres with a solid core and mesoporous shell (mSiO2/SiO2) on cellular internalization in mouse fibroblast cells (L929) was evaluated. The physical properties of the nanostructures were characterized with various methods, such as transmission electron microscopy with x-ray dispersion spectroscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy and zeta potential. In order to define the cellular uptake, the nanostructures were labelled with fluorescent dye Alexa647, and imaging and quantitative methods were applied: laser scanning confocal microscopy, flow cytometry and thermogravimetry. Our results indicate that cellular uptake of the studied nanospheres is size-dependent, and nanospheres of 90 nm in diameter showed the most efficient cell internalization. Thus, particle size is an important parameter that determines cellular uptake of nanoparticles and should be considered in designing drug delivery carriers. PMID:26586672

  11. Orbital dependent ultrafast charge transfer dynamics of ferrocenyl-functionalized SAMs on gold studied by core-hole clock spectroscopy

    NASA Astrophysics Data System (ADS)

    Cao, Liang; Yang, Ming; Yuan, Li; Nerngchamnong, Nisachol; Feng, Yuan-Ping; Wee, Andrew T. S.; Qi, Dong-Chen; Nijhuis, Christian A.

    2016-03-01

    Understanding the charge transport properties in general of different molecular components in a self-assembled monolayer (SAM) is of importance for the rational design of SAM molecular structures for molecular electronics. In this study, we study an important aspect of the charge transport properties, i.e. the charge transfer (CT) dynamics between the active molecular component (in this case, the ferrocenyl moieties of a ferrocenyl-n-alkanethiol SAM) and the electrode using synchrotron-based core-hole clock (CHC) spectroscopy. The characteristic CT times are found to depend strongly on the character of the ferrocenyl-derived molecular orbitals (MOs) which mediate the CT process. Furthermore, by systemically shifting the position of the ferrocenyl moiety in the SAM, it is found that the CT characteristics of the ferrocenyl MOs display distinct dependence on its distance to the electrode. These results demonstrate experimentally that the efficiency and rate of charge transport through the molecular backbone can be modulated by resonant injection of charge carriers into specific MOs.

  12. "An Easy Switch": A Descriptive Case Study Exploring the Shift toward Informational Text Accompanying the Implementation of Common Core State Standards in Five Primary Classrooms

    ERIC Educational Resources Information Center

    Kindall, Heather

    2013-01-01

    The purpose of this descriptive case study was to discover how the newly implemented Common Core State Standards (CCSS) may have changed teachers' practices and philosophies regarding literacy instruction and to determine which teaching strategies were being presented in regard to informational text in the studied Kindergarten through second grade…

  13. Developing a Consensus-Driven, Core Competency Model to Shape Future Audio Engineering Technology Curriculum: A Web-Based Modified Delphi Study

    ERIC Educational Resources Information Center

    Tough, David T.

    2009-01-01

    The purpose of this online study was to create a ranking of essential core competencies and technologies required by AET (audio engineering technology) programs 10 years in the future. The study was designed to facilitate curriculum development and improvement in the rapidly expanding number of small to medium sized audio engineering technology…

  14. Optimizing performance by improving core stability and core strength.

    PubMed

    Hibbs, Angela E; Thompson, Kevin G; French, Duncan; Wrigley, Allan; Spears, Iain

    2008-01-01

    Core stability and core strength have been subject to research since the early 1980s. Research has highlighted benefits of training these processes for people with back pain and for carrying out everyday activities. However, less research has been performed on the benefits of core training for elite athletes and how this training should be carried out to optimize sporting performance. Many elite athletes undertake core stability and core strength training as part of their training programme, despite contradictory findings and conclusions as to their efficacy. This is mainly due to the lack of a gold standard method for measuring core stability and strength when performing everyday tasks and sporting movements. A further confounding factor is that because of the differing demands on the core musculature during everyday activities (low load, slow movements) and sporting activities (high load, resisted, dynamic movements), research performed in the rehabilitation sector cannot be applied to the sporting environment and, subsequently, data regarding core training programmes and their effectiveness on sporting performance are lacking. There are many articles in the literature that promote core training programmes and exercises for performance enhancement without providing a strong scientific rationale of their effectiveness, especially in the sporting sector. In the rehabilitation sector, improvements in lower back injuries have been reported by improving core stability. Few studies have observed any performance enhancement in sporting activities despite observing improvements in core stability and core strength following a core training programme. A clearer understanding of the roles that specific muscles have during core stability and core strength exercises would enable more functional training programmes to be implemented, which may result in a more effective transfer of these skills to actual sporting activities. PMID:19026017

  15. Synthesis and steady-state photophysical properties of dye-labeled dendrimers having novel oligothiophene cores: A comparative study

    SciTech Connect

    Adronov, A.; Malenfant, P.R.L.; Frechet, J.M.J.

    2000-05-01

    Novel chromophore-labeled dendrimers with penta- and heptathiophene cores and coumarin-2 chromophores at their periphery have been shown to be very efficient light-harvesting systems. Excitation of the peripheral coumarin-2 chromophores results in energy transfer to the oligothiophene cores as a result of the large overlap between the donor emission spectrum and the acceptor absorption spectrum, as well as the large transition dipole moments of the oligothiophenes. Although these core dyes have low fluorescence quantum yields, their emission intensity is significantly enhanced by the ability of the large light-harvesting dendron to funnel absorbed energy to the core. Because of the large Stokes shift of the oligothiophenes, the emission spectrum of the dendrimers was red-shifted by 200 nm from the excitation wavelength. Additionally, it was found that oligothiophene orientation--end functionalization vs central functionalization--did not have a significant effect on energy-transfer efficiency.

  16. Trace elements profiles, notably Hg, from a preliminary study of the Apollo 15 deep-drill core.

    NASA Technical Reports Server (NTRS)

    Jovanovic, S.; Reed, G. W., Jr.

    1972-01-01

    The possible thermal gradient near the surface during a lunation is considered together with the heat flow from the interior, the physical process of Hg migration, the results from core and trench samples from previous missions, and other temperature sensitive phenomena that may help understand the processes. U, Os, and Ru concentrations in the deep drill core samples are of potential interest and are summarized in a table. The Os tends to parallel the Hg profile with depth.

  17. Combining Concentrated Autologous Bone Marrow Stem Cells Injection With Core Decompression Improves Outcome for Patients with Early-Stage Osteonecrosis of the Femoral Head: A Comparative Study.

    PubMed

    Tabatabaee, Reza Mostafavi; Saberi, Sadegh; Parvizi, Javad; Mortazavi, Seyed Mohammad Javad; Farzan, Mahmoud

    2015-09-01

    The management of early-stage osteonecrosis of the femoral head (ONFH) remains challenging. This study aimed to evaluate the effects of core decompression and concentrated bone marrow implantation on ONFH. The study recruited 28 hips with early ONFH randomly assigned into two groups of core decompression with (group A) and without (group B) bone marrow injection. Patients were evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire, Visual Analogue Scale (VAS) pain index, and MRI. The mean WOMAC and VAS scores in all patients improved significantly (P<0.001). MRI showed a significant improvement in group A (P=0.046) and significant worsening in group B (P<0.001). Bone marrow stem cell injection with core decompression can be effective in early ONFH. PMID:26143238

  18. Multireference study of spin-orbit coupling in the hydrides of the 6p-block elements using the model core potential method

    NASA Astrophysics Data System (ADS)

    Zeng, Tao; Fedorov, Dmitri G.; Klobukowski, Mariusz

    2010-02-01

    Careful spin-orbit multireference studies were carried out for the late p-block elements Tl, Pb, Bi, Po, At, and Rn and their hydrides using the model core potentials developed in the present work. The model core potentials were designed to treat the scalar-relativistic and spin-orbit coupling effects at the Douglas-Kroll level. The variational stability of the spin-orbit coupling operator was discussed in terms of the relativistic kinematic operators and depicted graphically. A detailed analysis of the spin-orbit multireference dissociation curves of the 6p element hydrides as well as of their atomic spectra allowed to establish the accuracy of the model core potentials with respect to all-electron calculations to be within several mÅ for re, meV (ceV) for De at the correlation level of configuration interaction (multireference perturbation theory), 30 cm-1 for ωe, and about 350 cm-1 for the low-lying atomic and molecular term and level energies. These values are expected to be the maximum error limits for the model core potentials of all the np-block elements (n =2-6). Furthermore, a good agreement with experiment requires that many terms be coupled in the spin-orbit coupling calculations. A timing study of Tl and TlH computations indicates that the model core potentials lead to 20-fold (6-fold) speedup at the level of configuration interaction (multireference perturbation theory) calculations.

  19. Study of field-pole Bi2223 windings of air core type for a HTS propulsion motor

    NASA Astrophysics Data System (ADS)

    Sugyo, D.; Kimura, Y.; Sano, T.; Yamaguchi, K.; Izumi, M.; Miki, M.; Ohmatu, K.; Fukumoto, Y.; Fujimoto, H.

    2008-02-01

    In the present study, we designed a field pole of Bi2223 superconductor winding without iron core applied to high-temperature superconducting (HTS) motor of an axial gap type. As the preliminary step to form a field pole winding, we designed a double-pancake-coil (DPC) and qualified relationship between the terminal voltage and the excitation current. We adopted the structure of HTS winding field pole composed of stacked two layered DPC because of effective conduction cooling and electromagnetic effect. We manufactured 16 poles DPC and verified the critical current vs. terminal voltage at 77 K with liquid nitrogen. To form a rotor, 8 field-pole HTS windings were manufactured by integrating of two DPCs as a split coil. We measured the coil Ic and voltage drop of the terminal at 30 K cooled with gas-liquid mixing helium and qualified the heat generation from the coils with DC current excitation. The cooling and excitation test of the constructed field pole coils were performed in the testing motor. The results exhibit that presently developed coils possesses sufficient performance on the heat generation and the magnetic flux density in the axial-type machine under construction.

  20. High frequency study of core-shell reusable CoFe2O4-ZnO nanospheres

    NASA Astrophysics Data System (ADS)

    Kuanr, Bijoy K.; Veerakumar, V.; Mishra, S. R.; Wilson, Armstrong M.; Kuanr, Alka V.; Camley, R. E.; Celinski, Z.

    2014-05-01

    Recently, coated nanoshells combined with magnetic nanoparticles and cancer-cell-specific antibodies have been used to develop a multifunctional platform for simultaneously diagnosing and treating cancer, via magnetic resonance imaging and photothermal therapy. For this application, core-shell nano-spheres with a low resonance frequency (low GHz range) in a strong applied field are required. In this aspect, ferromagnetic resonance experiment is an important tool for determining the dynamic properties of nano-materials. Magnetic field dependence of resonance frequency (fr) and linewidths (Δƒ and ΔH) for both the ZnO coated and uncoated CoFe2O4 hollow spheres are studied using a vector network analyzer. As compared to uncoated CoFe2O4 hollow sphere, ZnO coated CoFe2O4 showed reduced resonance frequency, larger Δƒ and ΔH, reduced gyromagnetic ratio and effective fields. The experimental results are confirmed with the effective medium theory.

  1. Evidence for Gamow-Teller Decay of ^{78}Ni Core from Beta-Delayed Neutron Emission Studies.

    PubMed

    Madurga, M; Paulauskas, S V; Grzywacz, R; Miller, D; Bardayan, D W; Batchelder, J C; Brewer, N T; Cizewski, J A; Fijałkowska, A; Gross, C J; Howard, M E; Ilyushkin, S V; Manning, B; Matoš, M; Mendez, A J; Miernik, K; Padgett, S W; Peters, W A; Rasco, B C; Ratkiewicz, A; Rykaczewski, K P; Stracener, D W; Wang, E H; Wolińska-Cichocka, M; Zganjar, E F

    2016-08-26

    The β-delayed neutron emission of ^{83,84}Ga isotopes was studied using the neutron time-of-flight technique. The measured neutron energy spectra showed emission from states at excitation energies high above the neutron separation energy and previously not observed in the β decay of midmass nuclei. The large decay strength deduced from the observed intense neutron emission is a signature of Gamow-Teller transformation. This observation was interpreted as evidence for allowed β decay to ^{78}Ni core-excited states in ^{83,84}Ge favored by shell effects. We developed shell model calculations in the proton fpg_{9/2} and neutron extended fpg_{9/2}+d_{5/2} valence space using realistic interactions that were used to understand measured β-decay lifetimes. We conclude that enhanced, concentrated β-decay strength for neutron-unbound states may be common for very neutron-rich nuclei. This leads to intense β-delayed high-energy neutron and strong multineutron emission probabilities that in turn affect astrophysical nucleosynthesis models. PMID:27610848

  2. Magnetic and transport studies of core-shell nanorods based on metallic oxide ferromagnet SrRuO3

    NASA Astrophysics Data System (ADS)

    Zheng, M.; Li, X. Y.; Zhu, Q. X.; Li, H. R.; Shi, L.; Li, X. M.; Zheng, R. K.

    2016-01-01

    This study presents the synthesis of perovskite metal-semiconductor core-shell heterostructures by sputtering SrRuO3 (SRO) shell layer on vertically aligned hydrothermally produced ZnO nanorods. Compared to the two-dimensional SRO films, the magnetic behaviors of the SRO shells on ZnO nanorods are morphology and thickness dependent, as reflected by the magnetic isotropy effects and the appearance of double-step magnetic hysteresis loops caused by nanograin-induced disorder and uncompensated spin at the surface and interface. The appearance of low-temperature resistance minimum and the good fitting of the low-temperature resistance data to a theoretical model establish the emergence of weak localization effect in the SRO shells, whose strength can be reinforced by a magnetic field. In addition, an apparent low-resistance Ohmic contact was realized in the ZnO/SRO heterojunctions due to the lower work function of the SRO. This, together with the absence of the Schottky barrier at the interface, demonstrates that the ZnO/SRO nanostructures could hold great promise for applications in advanced electron field emitters.

  3. A Genome-Wide Association Study Reveals Genes Associated with Fusarium Ear Rot Resistance in a Maize Core Diversity Panel

    PubMed Central

    Zila, Charles T.; Samayoa, L. Fernando; Santiago, Rogelio; Butrón, Ana; Holland, James B.

    2013-01-01

    Fusarium ear rot is a common disease of maize that affects food and feed quality globally. Resistance to the disease is highly quantitative, and maize breeders have difficulty incorporating polygenic resistance alleles from unadapted donor sources into elite breeding populations without having a negative impact on agronomic performance. Identification of specific allele variants contributing to improved resistance may be useful to breeders by allowing selection of resistance alleles in coupling phase linkage with favorable agronomic characteristics. We report the results of a genome-wide association study to detect allele variants associated with increased resistance to Fusarium ear rot in a maize core diversity panel of 267 inbred lines evaluated in two sets of environments. We performed association tests with 47,445 single-nucleotide polymorphisms (SNPs) while controlling for background genomic relationships with a mixed model and identified three marker loci significantly associated with disease resistance in at least one subset of environments. Each associated SNP locus had relatively small additive effects on disease resistance (±1.1% on a 0–100% scale), but nevertheless were associated with 3 to 12% of the genotypic variation within or across environment subsets. Two of three identified SNPs colocalized with genes that have been implicated with programmed cell death. An analysis of associated allele frequencies within the major maize subpopulations revealed enrichment for resistance alleles in the tropical/subtropical and popcorn subpopulations compared with other temperate breeding pools. PMID:24048647

  4. Core-level Photoemission Study for Cuprates with a Dynamical Mean-Field Approach Considering Realistic Crystal Structure

    NASA Astrophysics Data System (ADS)

    Hariki, Atsushi; Uozumi, Takayuki

    2013-03-01

    Recently, remarkable experimental progress reveals some characteristic spectral features in the 2p3/2main line of Cu 2p core-level X-ray photoemission spectra (XPS). The structures show strong material dependence and drastic changes for electron or hole doping. Van Veenendaal et al., pointed out that the main line shape is strongly affected by the so-called nonlocal screening which is accompanied by a formation of a Zhang-Rice singlet (ZRS) in the XPS final state. On the other hand, Taguchi et al., shows these features are reproduced by introducing an phenomenological extended impurity model. We consider that this topic on 2pXPS of cuprates still remain controversial. In this study, we propose another approach based on the dynamical mean field theory(DMFT) considering the realistic crystal structure. Many-particle effects including the ZRS is appropriately embedded in the hybridization function of a single impurity Anderson model through the DMFT self-consistent cycle. Our approach reproduces experimental results and shows that the Cu 2p3/2 main line is closely related with the quasi-particle structure near the Fermi energy.

  5. NLOphoric Red Emitting Bis Coumarins with O-BF(2)-O core - Synthesis, Photophysical Properties and DFT Studies.

    PubMed

    Tathe, Abhinav B; Sekar, Nagaiyan

    2016-03-01

    The red emitting dyes were synthesized by employing coumarin core as a donor and boron-bonded coumarin as an acceptor. 7-(N,N-Diethylamino)-coumarin 3-aldehyde was reacted with 3-acetyl-4-hydroxy-coumarin, 7-(N,N-diethylamino)-3-acetyl-4-hydroxy-coumarin and 3-acetyl-4-hydroxy-1-methyl-quinolone to form the corresponding chalcones. The synthesized chalcones were though red shifted as compared to the parent coumarin, and were not emitting in red region. The BF2-complexation was used as a tool to introduce a red shift in the molecules. The BF2-complexes synthesized were found to be red emitting and show higher one photon absorption cross section. The solvatochromism shown by these dyes was studied in the light of solvent polarity parameters. DFT calculations were used to understand the photophysical properties of the synthesized dyes. NLO properties of the dyes were estimated by solvatochromic and computational methods. All the molecules synthesized were characterised with the HRMS and NMR spectral Analysis. PMID:26662811

  6. Synthesis of branched cores by poly-O-alkylation reaction under phase transfer conditions. A systematic study

    NASA Astrophysics Data System (ADS)

    Landeros, José M.; Silvestre, Hugo A.; Guadarrama, Patricia

    2013-04-01

    In the present paper is described a systematic study of poly-O-alkylation reactions of pentaerythritol (PE) and 1,1,1-tris(hydroxymethyl)ethane (TME) by 1,4 Michael addition, under phase transfer catalysis (PTC), considering the effect of: (1) the organophilicity of PTC (three different catalysts were tested), (2) PTC concentration (from catalytic to equimolar conditions), and (3) the regime of addition of reactants coexisting in the aqueous phase of the heterogeneous reaction system. The less organophilic transfer agent showed the best performance on these reactions. In our case, benzyltriethylammonium chloride (TEBAC) gathers the best features. The presence of NaOH as base, promotes the interfacial mechanism and not the bulk one. Out of the optimal range of concentration of NaOH (35-40%), competition between nucleophiles can occur, due to the saturation of the medium. Regarding the regime of addition of reactants, the scenario where NaOH and TEBAC are less time in contact, favors the formation of the desired products. Finally, the deprotection of tert-butyl groups of the poly-O-alkylated compounds is described, to get branched cores with terminal carboxylic acid groups in good yields (90-94%). Spectroscopic properties, such as IR, 1H and 13C NMR, of the synthesized compounds are also described.

  7. A genome-wide association study reveals genes associated with fusarium ear rot resistance in a maize core diversity panel.

    PubMed

    Zila, Charles T; Samayoa, L Fernando; Santiago, Rogelio; Butrón, Ana; Holland, James B

    2013-11-01

    Fusarium ear rot is a common disease of maize that affects food and feed quality globally. Resistance to the disease is highly quantitative, and maize breeders have difficulty incorporating polygenic resistance alleles from unadapted donor sources into elite breeding populations without having a negative impact on agronomic performance. Identification of specific allele variants contributing to improved resistance may be useful to breeders by allowing selection of resistance alleles in coupling phase linkage with favorable agronomic characteristics. We report the results of a genome-wide association study to detect allele variants associated with increased resistance to Fusarium ear rot in a maize core diversity panel of 267 inbred lines evaluated in two sets of environments. We performed association tests with 47,445 single-nucleotide polymorphisms (SNPs) while controlling for background genomic relationships with a mixed model and identified three marker loci significantly associated with disease resistance in at least one subset of environments. Each associated SNP locus had relatively small additive effects on disease resistance (±1.1% on a 0-100% scale), but nevertheless were associated with 3 to 12% of the genotypic variation within or across environment subsets. Two of three identified SNPs colocalized with genes that have been implicated with programmed cell death. An analysis of associated allele frequencies within the major maize subpopulations revealed enrichment for resistance alleles in the tropical/subtropical and popcorn subpopulations compared with other temperate breeding pools. PMID:24048647

  8. A STUDY OF THE DARK CORE IN A520 WITH THE HUBBLE SPACE TELESCOPE: THE MYSTERY DEEPENS

    SciTech Connect

    Jee, M. J.; Mahdavi, A.; Hoekstra, H.; Babul, A.; Dalcanton, J. J.; Carroll, P.; Capak, P.

    2012-03-10

    We present a Hubble Space Telescope/Wide Field Planetary Camera 2 weak-lensing study of A520, where a previous analysis of ground-based data suggested the presence of a dark mass concentration. We map the complex mass structure in much greater detail, leveraging more than a factor of three increase in the number density of source galaxies available for lensing analysis. The 'dark core' that is coincident with the X-ray gas peak, but not with any stellar luminosity peak, is now detected with more than 10{sigma} significance. The {approx}1.5 Mpc filamentary structure elongated in the NE-SW direction is also clearly visible. Taken at face value, the comparison among the centroids of dark matter, intracluster medium, and galaxy luminosity is at odds with what has been observed in other merging clusters with a similar geometric configuration. To date, the most remarkable counterexample might be the Bullet Cluster, which shows a distinct bow-shock feature as in A520, but no significant weak-lensing mass concentration around the X-ray gas. With the most up-to-date data, we consider several possible explanations that might lead to the detection of this peculiar feature in A520. However, we conclude that none of these scenarios can be singled out yet as the definite explanation for this puzzle.

  9. A Panel of Recombinant Mucins Carrying a Repertoire of Sialylated O-Glycans Based on Different Core Chains for Studies of Glycan Binding Proteins.

    PubMed

    Cherian, Reeja Maria; Jin, Chunsheng; Liu, Jining; Karlsson, Niclas G; Holgersson, Jan

    2015-01-01

    Sialylated glycans serve as key elements of receptors for many viruses, bacteria, and bacterial toxins. The microbial recognition and their binding specificity can be affected by the linkage of the terminal sugar residue, types of underlying sugar chains, and the nature of the entire glycoconjugate. Owing to the pathobiological significance of sialylated glycans, we have engineered Chinese hamster ovary (CHO) cells to secrete mucin-type immunoglobulin-fused proteins carrying terminal α2,3- or α2,6-linked sialic acid on defined O-glycan core saccharide chains. Besides stably expressing P-selectin glycoprotein ligand-1/mouse immunoglobulin G2b cDNA (PSGL-1/mIgG2b), CHO cells were stably transfected with plasmids encoding glycosyltransferases to synthesize core 2 (GCNT1), core 3 (B3GNT6), core 4 (GCNT1 and B3GNT6), or extended core 1 (B3GNT3) chains with or without the type 1 chain-encoding enzyme B3GALT5 and ST6GAL1. Western blot and liquid chromatography-mass spectrometry analysis confirmed the presence of core 1, 2, 3, 4, and extended core 1 chains carrying either type 1 (Galb3GlcNAc) or type 2 (Galb4GlcNAc) outer chains with or without α2,6-linked sialic acids. This panel of recombinant mucins carrying a repertoire of sialylated O-glycans will be important tools in studies aiming at determining the fine O-glycan binding specificity of sialic acid-specific microbial adhesins and mammalian lectins. PMID:26274979

  10. A Panel of Recombinant Mucins Carrying a Repertoire of Sialylated O-Glycans Based on Different Core Chains for Studies of Glycan Binding Proteins

    PubMed Central

    Maria Cherian, Reeja; Jin, Chunsheng; Liu, Jining; Karlsson, Niclas G.; Holgersson, Jan

    2015-01-01

    Sialylated glycans serve as key elements of receptors for many viruses, bacteria, and bacterial toxins. The microbial recognition and their binding specificity can be affected by the linkage of the terminal sugar residue, types of underlying sugar chains, and the nature of the entire glycoconjugate. Owing to the pathobiological significance of sialylated glycans, we have engineered Chinese hamster ovary (CHO) cells to secrete mucin-type immunoglobulin-fused proteins carrying terminal α2,3- or α2,6-linked sialic acid on defined O-glycan core saccharide chains. Besides stably expressing P-selectin glycoprotein ligand-1/mouse immunoglobulin G2b cDNA (PSGL-1/mIgG2b), CHO cells were stably transfected with plasmids encoding glycosyltransferases to synthesize core 2 (GCNT1), core 3 (B3GNT6), core 4 (GCNT1 and B3GNT6), or extended core 1 (B3GNT3) chains with or without the type 1 chain-encoding enzyme B3GALT5 and ST6GAL1. Western blot and liquid chromatography-mass spectrometry analysis confirmed the presence of core 1, 2, 3, 4, and extended core 1 chains carrying either type 1 (Galβ3GlcNAc) or type 2 (Galβ4GlcNAc) outer chains with or without α2,6-linked sialic acids. This panel of recombinant mucins carrying a repertoire of sialylated O-glycans will be important tools in studies aiming at determining the fine O-glycan binding specificity of sialic acid-specific microbial adhesins and mammalian lectins. PMID:26274979

  11. Retrospective study investigating the prevalence and clinical significance of hepatitis B virus precore and basal core promoter variants

    PubMed Central

    O’Brien, Meaghan; Casselman, Adara; Smart, Gerry; Gretchen, Ainsley; Kaita, Kelly; Kadkhoda, Kamran

    2015-01-01

    BACKGROUND: Hepatitis B virus (HBV) precore (PC) and basal core promoter (BCP) variants are well known; however, their prevalence in North America is unclear, especially among hepatitis B e antigen-negative patients. OBJECTIVE: To investigate the prevalence of PC/BCP mutations and their clinical significance. METHODS: One hundred twenty-eight patients positive for both hepatitis B surface antigen and hepatitis B e antibody were selected, and PC/BCP mutations were identified using a line probe assay. The subjects’ charts were reviewed for race/ethnicity, HBV genotype, HBV viral load, sex, liver enzyme levels, imaging and biopsy results up to 10 years before the study. RESULTS: The prevalence of PC and BCP variants were 47.6% and 62.5%, respectively. Older age was associated with aspartate aminotransferase-to-platelet index ratio (APRI) ≥0.7 (P=0.011) and abnormal imaging/biopsy results (P=0.0008). Although the presence of BCP variant(s) was associated with APRI ≥0.7 (P=0.029), it was not associated with abnormal imaging/biopsy results. The combination of age ≥50 years and the presence of BCP variant(s) was associated with abnormal imaging/biopsy results, suggestive of either cirrhosis or hepatocellular carcinoma (not observed with PC mutation). Neither sex or genotype, or median HBV viral load showed significant influence on any of these outcomes. CONCLUSIONS: The present study suggests that the prevalence of PC and BCP mutations are higher than what has been previously reported. One potential explanation would be increased immigration in the past decade. Considering the potential public health and clinical implications of these variants, long-term multicentre and prospective studies could further unravel the uncertainty around these variants. PMID:26401823

  12. Core Directions in HRD.

    ERIC Educational Resources Information Center

    1996

    This document consists of four papers presented at a symposium on core directions in human resource development (HRD) moderated by Verna Willis at the 1996 conference of the Academy of Human Resource Development. "Reengineering the Organizational HRD Function: Two Case Studies" (Neal Chalofsky) reports an action research study in which the…

  13. Ferromagnetic resonance and magnetic studies of cores 60009/60010 and 60003 - Compositional and surface-exposure stratigraphy. [of Apollo deep drill lunar samples

    NASA Technical Reports Server (NTRS)

    Morris, R. V.; Gose, W. A.

    1976-01-01

    Ferromagnetic resonance and static magnetic measurements were made on 131 samples from core 60009/60010 and on 40 samples from section 60003 of the Apollo 16 deep drill core. These studies provided depth profiles for composition, in terms of the concentration of FeO, and relative surface exposure age (or maturity), in terms of the values of the specific FMR intensity normalized to the FeO content. For core 60009/60010, the concentration of FeO ranged from about 1.6 wt.% to 5.8 wt.% with a mean value of 4.6 wt.% and the maturity ranged from immature to mature with most of the soils being submature. A systematic decrease in maturity from the lunar surface to a depth of about 12.5 cm was observed in core section 60010. For core section 60003, the concentration of FeO ranged from about 5.2 wt.% to 7.5 wt.% with a mean value of 6.4 wt.% and the maturity ranged from submature to mature with most of the soils being mature.

  14. Co-electrospinning fabrication and study of structural and electromagnetic interference-shielding effectiveness of TiO2/SiO2 core-shell nanofibers

    NASA Astrophysics Data System (ADS)

    Nakhaei, Omolfajr; Shahtahmassebi, Nasser; Rezaee Roknabadi, Mahmood; Behdani, Mohammad

    2016-05-01

    The present paper reports novel outcome comprising experimental results on electromagnetic interference (EMI) shielding and radar signal absorption characteristics of one-dimensional (1D) TiO2/SiO2 core-shell nanofibers. 1D TiO2/SiO2 core-shell nanofibers with various concentrations of nanoparticles (NPs) were fabricated using a single-nozzle co-electrospinning method. The core-shell structure of polyvinylpyrrolidone/polyacrylonitrile nanofibers with NPs have been electrospun from the homogeneous solution of polyvinylpyrrolidone (PVP and TiO2 NPs, as core) and polyacrylonitrile (PAN and SiO2 NPs, as shell). The morphologies and structures of TiO2/SiO2 core-shell nanofibers were characterized by XRD, FTIR, EDS, and SEM images. Microwave absorption properties of the synthesized nanofibers were studied using a vector network analyzer between 2 and 20 GHz at room temperature. The maximum EMI-shielding effectiveness of 150 dB is obtained with the dominant shielding mechanism of absorption of EM radiation. The excellent microwave absorption properties of the composites nanofibers are attributed to the special 1D fibrous structure and the effective dielectric loss.

  15. Difference in fibril core stability between two tau four-repeat domain proteins: a hydrogen-deuterium exchange coupled to mass spectrometry study.

    PubMed

    Ramachandran, Gayathri; Udgaonkar, Jayant B

    2013-12-10

    One of the signatures of Alzheimer's disease and tauopathies is fibrillization of the microtubule-associated protein tau. The purpose of this study was to compare the high-resolution structure of fibrils formed by two different tau four-repeat domain constructs, tau4RD and tauK18, using hydrogen-deuterium exchange coupled to mass spectrometry as a tool. While the two fibrils are found to be constructed on similar structural principles, the tauK18 fibril has a slightly more stable core. This difference in fibril core stability appears to be reflective of the mechanistic differences in the aggregation pathways of the two proteins. PMID:24256615

  16. Emotional Intolerance and Core Features of Anorexia Nervosa: A Dynamic Interaction during Inpatient Treatment? Results from a Longitudinal Diary Study

    PubMed Central

    Stroe-Kunold, Esther; Friederich, Hans-Christoph; Stadnitski, Tatjana; Wesche, Daniela; Herzog, Wolfgang; Schwab, Michael; Wild, Beate

    2016-01-01

    Objective The role of emotion dysregulation with regard to the psychopathology of anorexia nervosa (AN) is increasingly discussed. It is both assumed that AN symptoms have an impact on difficulties in tolerating aversive emotions and that—conversely—emotion dysregulation influences AN. To date, such conclusions are drawn on the basis of cross-sectional data not allowing for inferences on the temporal dynamics. The current study investigates the longitudinal interaction between emotional intolerance and core AN symptoms over the course of inpatient treatment by comparing patients with high (BMI<15 kg/m2) vs. low symptom severity (HSS vs. LSS). Method The study adopted a longitudinal, process-oriented design with N = 16 analysed electronic diaries. Throughout the course of their inpatient treatment, the patients answered questions daily about emotional intolerance and their AN-specific cognitions and behaviours. The temporal dynamics between emotional intolerance and these variables were analysed using a multivariate time series approach. Results The time series of the processes under investigation adequately reflected the individual treatment courses. The majority of significant linear time trends was found for HSS patients. Most importantly, analysis revealed significant temporal interactions between emotional intolerance and AN symptoms in almost 70% of HSS patients. Thereby, up to 37% of variance in eating restraint and up to 23% in weight concern could be attributed to changes in emotional intolerance. Conclusions The findings support the notion that intolerable unpleasant emotions in severely affected AN patients influence their psychopathology. Additionally, time series analysis outlined the inter-individual heterogeneity of psychosomatic treatment courses of AN patients. PMID:27191959

  17. Reorienting health services with capacity building: a case study of the Core Skills in Health Promotion Project.

    PubMed

    Yeatman, H R; Nove, T

    2002-12-01

    This paper presents a case study of the application of a framework for capacity building [Hawe, P., King, L., Noort, M., Jordens, C. and Lloyd, B. (2000) Indicators to Help with Capacity Building in Health Promotion. NSW Health, Sydney] to describe actions aimed at building organizational support for health promotion within an area health service in New South Wales, Australia. The Core Skills in Health Promotion Project (CSHPP) arose from an investigation which reported that participants of a health promotion training course had increased health promotion skills but that they lacked the support to apply their skills in the workplace. The project was action-research based. It investigated and facilitated the implementation of a range of initiatives to support community health staff to apply a more preventive approach in their practice and it contributed to the establishment of new organizational structures for health promotion. An evaluation was undertaken 4 years after the CSHPP was established, and 2 years after it had submitted its final report. Interviews with senior managers, document analysis of written reports, and focus groups with middle managers and service delivery staff were undertaken. Change was achieved in the three dimensions of health infrastructure, program maintenance and problem solving capacity of the organization. It was identified that the critically important elements in achieving the aims of the project-partnership, leadership and commitment-were also key elements of the capacity building framework. This case study provides a practical example of the usefulness of the capacity building framework in orienting health services to be supportive of health promotion. PMID:12406922

  18. A Giant Metrewave Radio Telescope Multifrequency Radio Study of the Isothermal Core of the Poor Galaxy Cluster AWM 4

    NASA Astrophysics Data System (ADS)

    Giacintucci, Simona; Vrtilek, Jan M.; Murgia, Matteo; Raychaudhury, Somak; O'Sullivan, Ewan J.; Venturi, Tiziana; David, Laurence P.; Mazzotta, Pasquale; Clarke, Tracy E.; Athreya, Ramana M.

    2008-07-01

    We present a detailed radio morphological study and spectral analysis of the wide-angle tail radio source 4C +24.36 associated with the dominant galaxy in the relaxed galaxy cluster AWM 4. Our study is based on new high-sensitivity GMRT observations at 235, 327, and 610 MHz and on literature and archival data at other frequencies. We find that the source major axis is likely oriented at a small angle with respect to the plane of the sky. The wide-angle tail morphology can be reasonably explained by adopting a simple hydrodynamical model in which both ram pressure (driven by the motion of the host galaxy) and buoyancy forces contribute to bend the radio structure. The spectral index progressively steepens along the source major axis from α ~ 0.3 in the region close to the radio nucleus to beyond 1.5 in the lobes. The results of the analysis of the spectral index image allow us to derive an estimate of the radiative age of the source of ~160 Myr. The cluster X-ray-emitting gas has a relaxed morphology and short cooling time, but its temperature profile is isothermal out to at least 160 kpc from the center. Therefore, we seek evidence of energy ejection from the central AGN to prevent catastrophic cooling. We find that the energy injected by 4C +24.36 in the form of synchrotron luminosity during its lifetime is far less than the energy required to maintain the high gas temperature in the core. We also find that it is not possible for the central source to eject the requisite energy in the intracluster gas in terms of the enthalpy of buoyant bubbles of relativistic fluid, without creating discernible large cavities in the existing X-ray XMM-Newton observations.

  19. Glycerol capped PbS/CdS core/shell nanoparticles at different molar ratio and its application in biosensors: An optical properties study

    NASA Astrophysics Data System (ADS)

    Das, D.; Hussain, A. M. P.

    2016-05-01

    Glycerol capped PbS/CdS core/shell type nanoparticles fabricated with two different molar ratios are characterized for study of structural and optical properties. The X-ray diffraction (XRD) pattern exhibits cubic phased polycrystalline nanocrystals. The calculated grain sizes from Williamson-Hall plot were found to be around 6 nm with increased strain. HRTEM investigation confirms the formation of core/shell nanostructures and the sizes of the particles were found to be around 7 nm which is in good agreement with the results of the W-H plot. An increase of band gap with the decrease in precursor concentration is confirmed from the blue shift in the absorption spectra and also from Tauc plot. A clear blue shifted intense emission is observed in the photoluminescence spectra with decrease in particle size. Intense luminescence from the core/shell nanostructure may be applied in bio labelling and biosensors.

  20. Real-space pseudopotential study of vibrational properties and Raman spectra in Si-Ge core-shell nanocrystals

    NASA Astrophysics Data System (ADS)

    Bobbitt, N. Scott; Chelikowsky, James R.

    2016-03-01

    We examine the vibrational properties and Raman spectra of Si-Ge core-shell nanostructures using real-space pseudopotentials constructed within density functional theory. Our method uses no empirical parameters, unlike many popular methods for predicting Raman spectra for nanocrystals. We find the dominant features of the Raman spectrum for the Si-Ge core-shell structure to be a superposition of the Raman spectra of the Ge and Si nanocrystals with optical peaks around 300 and 500 cm-1, respectively. We also find a Si-Ge "interface" peak at 400 cm-1. The Ge shell causes the Si core to expand from the equilibrium structure. This strain induces significant redshift in the Si contribution to the vibrational and Raman spectra, while the Ge shell is largely unstrained and does not exhibit this shift. We find that the ratio of peak heights is strongly related to the relative size of the core and shell regions. This finding suggests that Raman spectroscopy may be used to characterize the size of the core and shell in these structures.

  1. Magnetization measurements and XMCD studies on ion irradiated iron oxide and core-shell iron/iron-oxide nanomaterials

    SciTech Connect

    Kaur, Maninder; Qiang, You; Jiang, Weilin; Pearce, Carolyn; McCloy, John S.

    2014-12-02

    Magnetite (Fe3O4) and core-shell iron/iron-oxide (Fe/Fe3O4) nanomaterials prepared by a cluster deposition system were irradiated with 5.5 MeV Si2+ ions and the structures determined by x-ray diffraction as consisting of 100% magnetite and 36/64 wt% Fe/FeO, respectively. However, x-ray magnetic circular dichroism (XMCD) indicates similar surfaces in the two samples, slightly oxidized and so having more Fe3+ than the expected magnetite structure, with XMCD intensity much lower for the irradiated core-shell samples indicating weaker magnetism. X-ray absorption spectroscopy (XAS) data lack the signature for FeO, but the irradiated core-shell system consists of Fe-cores with ~13 nm of separating oxide crystallite, so it is likely that FeO exists deeper than the probe depth of the XAS (~5 nm). Exchange bias (Hex) for both samples becomes increasingly negative as temperature is lowered, but the irradiated Fe3O4 sample shows greater sensitivity of cooling field on Hex. Loop asymmetries and Hex sensitivities of the irradiated Fe3O4 sample are due to interfaces and interactions between grains which were not present in samples before irradiation as well as surface oxidation. Asymmetries in the hysteresis curves of the irradiated core/shell sample are related to the reversal mechanism of the antiferromagnetic FeO and possibly some near surface oxidation.

  2. Pressure Core Characterization

    NASA Astrophysics Data System (ADS)

    Santamarina, J. C.

    2014-12-01

    Natural gas hydrates form under high fluid pressure and low temperature, and are found in permafrost, deep lakes or ocean sediments. Hydrate dissociation by depressurization and/or heating is accompanied by a multifold hydrate volume expansion and host sediments with low permeability experience massive destructuration. Proper characterization requires coring, recovery, manipulation and testing under P-T conditions within the stability field. Pressure core technology allows for the reliable characterization of hydrate bearing sediments within the stability field in order to address scientific and engineering needs, including the measurement of parameters used in hydro-thermo-mechanical analyses, and the monitoring of hydrate dissociation under controlled pressure, temperature, effective stress and chemical conditions. Inherent sampling effects remain and need to be addressed in test protocols and data interpretation. Pressure core technology has been deployed to study hydrate bearing sediments at several locations around the world. In addition to pressure core testing, a comprehensive characterization program should include sediment analysis, testing of reconstituted specimens (with and without synthetic hydrate), and in situ testing. Pressure core characterization technology can be used to study other gas-charged formations such as deep sea sediments, coal bed methane and gas shales.

  3. Nursing Faculty Professional Development: A Study Using the National League for Nursing (NLN) Core Competencies for Nurse Educators for Development of Novice to Expert Nurse Educators

    ERIC Educational Resources Information Center

    Luoma, Kari L.

    2013-01-01

    The purpose of this quantitative research study was to identify core competencies that are most significant for nursing faculty to develop as they transition from novice to expert faculty. Professional development in a systematic approach may guide faculty to learn what is significant as they progress in the nurse faculty role. A quantitative…

  4. Imitation (Rather than Core Language) Predicts Pragmatic Development in Young Children with ASD: A Preliminary Longitudinal Study Using CDI Parental Reports

    ERIC Educational Resources Information Center

    Miniscalco, Carmela; Rudling, Maja; Råstam, Maria; Gillberg, Christopher; Johnels, Jakob Åsberg

    2014-01-01

    Background: Research in the last decades has clearly pointed to the important role of language and communicative level when trying to understand developmental trajectories in children with autism spectrum disorders (ASD). Aims: The purpose of this longitudinal study was to investigate whether (1) "core language skills", measured as…

  5. Unemployment in the Urban Core: An Analysis of Thirty Cities with Policy Recommendations. Praeger Special Studies in U.S. Economic, Social, and Political Issues.

    ERIC Educational Resources Information Center

    Friedlander, Stanley L.

    This study explores the determinants of urban unemployment in 30 major cities, particularly in the inner core slums among nonwhites and youth. Using data for 1960, a year of recession, and 1966, a year of prosperity, the author found that a factor which may be important under one set of economic conditions is not so in another cycle. Although…

  6. Profiling of energy deposition fields in a modular HTHR with annular core: Computational/experimental studies at the ASTRA critical facility

    SciTech Connect

    Boyarinov, V. F.; Garin, V. P.; Glushkov, E. S.; Zimin, A. A.; Kompaniets, G. V.; Nevinitsa, V. A.; Polyakov, D. N.; Ponomarev, A. S.; Ponomarev-Stepnoi, N. N.; Smirnov, O. N.; Fomichenko, P. A.; Chunyaev, E. I.; Marova, E. V.; Sukharev, Yu. P.

    2010-12-15

    The paper presents the results obtained from the computational/experimental studies of the spatial distribution of the {sup 235}U fission reaction rate in a critical assembly with an annular core and poison profiling elements inserted into the inner graphite reflector. The computational analysis was carried out with the codes intended for design computation of an HTHR-type reactor.

  7. Experimental study of low-loss single-mode performance in anti-resonant hollow-core fibers.

    PubMed

    Yu, Fei; Xu, Mengrong; Knight, Jonathan C

    2016-06-13

    Anti-resonant hollow-core fibers are optical fiber waveguides which exhibit very low dispersion, high damage threshold and ultra-low nonlinear response. However, they typically deliver the light in several spatial modes, whereas their application usually requires that they support a single spatial mode. We report the principles, fabrication, demonstration and characterization of anti-resonant hollow-core fibres with strong differential modal attenuations and low overall attenuations. These fibers perform as single-mode and are eminently suitable for delivery of powerful ultrashort optical pulses in machining, cutting, welding and multiphoton microscopy applications. PMID:27410316

  8. A carbon, nitrogen, and sulfur elemental and isotopic study in dated sediment cores from the Louisiana Shelf

    USGS Publications Warehouse

    Rosenbauer, R.J.; Swarzenski, P.W.; Kendall, C.; Orem, W.H.; Hostettler, F.D.; Rollog, M.E.

    2009-01-01

    Three sediment cores were collected off the Mississippi River delta on the Louisiana Shelf at sites that are variably influenced by recurring, summer-time water-column hypoxia and fluvial loadings. The cores, with established chronology, were analyzed for their respective carbon, nitrogen, and sulfur elemental and isotopic composition to examine variable organic matter inputs, and to assess the sediment record for possible evidence of hypoxic events. Sediment from site MRJ03-3, which is located close to the Mississippi Canyon and generally not influenced by summer-time hypoxia, is typical of marine sediment in that it contains mostly marine algae and fine-grained material from the erosion of terrestrial C4 plants. Sediment from site MRJ03-2, located closer to the mouth of the Mississippi River and at the periphery of the hypoxic zone (annual recurrence of summer-time hypoxia >50%), is similar in composition to core MRJ03-3, but exhibits more isotopic and elemental variability down-core, suggesting that this site is more directly influenced by river discharge. Site MRJ03-5 is located in an area of recurring hypoxia (annual recurrence >75%), and is isotopically and elementally distinct from the other two cores. The carbon and nitrogen isotopic composition of this core prior to 1960 is similar to average particulate organic matter from the lower Mississippi River, and approaches the composition of C3 plants. This site likely receives a greater input of local terrestrial organic matter to the sediment. After 1960 and to the present, a gradual shift to higher values of ??13C and ??15N and lower C:N ratios suggests that algal input to these shelf sediments increased as a result of increased productivity and hypoxia. The values of C:S and ??34S reflect site-specific processes that may be influenced by the higher likelihood of recurring seasonal hypoxia. In particular, the temporal variations in the C:S and ??34S down-core are likely caused by changes in the rate of

  9. Fissioning Plasma Core Reactor

    NASA Technical Reports Server (NTRS)

    Albright, Dennis; Butler, Carey; West, Nicole; Cole, John W. (Technical Monitor)

    2002-01-01

    Institute for Scientific Research, Inc. (ISR) research program consist of: 1.Study core physics by adapting existing codes: MCNP4C - Monte Carlo code; COMBINE/VENTURE - diffusion theory; SCALE4 - Monte Carlo, with many utility codes. 2. Determine feasibility and study major design parameters: fuel selection, temperature and reflector sizing. 3. Study reactor kinetics: develop QCALC1 to model point kinetics; study dynamic behavior of the power release.

  10. Model core potentials for studies of scalar-relativistic effects and spin-orbit coupling at Douglas-Kroll level. I. Theory and applications to Pb and Bi.

    PubMed

    Zeng, Tao; Fedorov, Dmitri G; Klobukowski, Mariusz

    2009-09-28

    A theory of model core potentials that can treat spin-orbit-coupling (SOC) effects at the level of Douglas-Kroll formalism has been developed. By storing the damping effect of kinematic operator in the Douglas-Kroll spin-orbit operator into an additional set of basis set contraction coefficients, the Breit-Pauli spin-orbit code in the GAMESS-US program was successfully used to perform Douglas-Kroll spin-orbit calculations. It was found that minute errors in the radial functions of valence orbitals lead to large errors in the spin-orbit energy levels and thus fitting the radial part of the spin-orbit matrix elements is necessary in model core potential parametrization. The first model core potentials that include the new formalism were developed for two 6p-block elements, Pb and Bi. The valence space of the 5p, 5d, 6s, and 6p orbitals was used because of the large SOC between the 5p and 6p orbitals. The model core potentials were validated in the calculations of atomic properties as well as spectroscopic constants of diatomic metal hydrides. The agreement between results of the model core potential and all-electron calculations was excellent, with energy errors of hundreds of cm(-1) and hundredths of eV, r(e) errors of thousandths of A, and omega(e) errors under 20 cm(-1). Two kinds of interplay between SOC effect and bonding process (antibonding and bonding SOC) were demonstrated using spin-free term potential curves of PbH and BiH. The present study is the first extension of the model core potential method beyond Breit-Pauli to Douglas-Kroll SOC calculations. PMID:19791854

  11. Postmortem Study of Validation of Low Signal on Fat-Suppressed T1-Weighted Magnetic Resonance Imaging as Marker of Lipid Core in Middle Cerebral Artery Atherosclerosis

    PubMed Central

    Yang, Wen-Jie; Zhao, Hai-Lu; Niu, Chun-Bo; Zhang, Bing; Xu, Yun; Wong, Ka-Sing; Ng, Ho-Keung

    2016-01-01

    Background and Purpose— High signal on T1-weighted fat-suppressed images in middle cerebral artery plaques on ex vivo magnetic resonance imaging was verified to be intraplaque hemorrhage histologically. However, the underlying plaque component of low signal on T1-weighted fat-suppressed images (LST1) has never been explored. Based on our experience, we hypothesized that LST1 might indicate the presence of lipid core within intracranial plaques. Methods— 1.5 T magnetic resonance imaging was performed in the postmortem brains to scan the cross sections of bilateral middle cerebral arteries. Then middle cerebral artery specimens were removed for histology processing. LST1 presence was identified on magnetic resonance images, and lipid core areas were measured on the corresponding histology sections. Results— Total 76 middle cerebral artery locations were included for analysis. LST1 showed a high specificity (96.9%; 95% confidence interval, 82.0%–99.8%) but a low sensitivity (38.6%; 95% confidence interval, 24.7%–54.5%) for detecting lipid core of all areas. However, the sensitivity increased markedly (81.2%; 95% confidence interval, 53.7%–95.0%) when only lipid cores of area ≥0.80 mm2 were included. Mean lipid core area was 5× larger in those with presence of LST1 than in those without (1.63±1.18 mm2 versus 0.32±0.31 mm2; P=0.003). Conclusions— LST1 is a promising imaging biomarker of identifying intraplaque lipid core, which may be useful to distinguish intracranial atherosclerotic disease from other intracranial vasculopathies and to assess plaque vulnerability for risk stratification of patients with intracranial atherosclerotic disease. In vivo clinical studies are required to explore the correlation between LST1 and clinical outcomes of patients with intracranial atherosclerotic disease. PMID:27462119

  12. Non-destructive Analysis of Oil-Contaminated Soil Core Samples by X-ray Computed Tomography and Low-Field Nuclear Magnetic Resonance Relaxometry: a Case Study

    PubMed Central

    Mitsuhata, Yuji; Nishiwaki, Junko; Kawabe, Yoshishige; Utsuzawa, Shin; Jinguuji, Motoharu

    2010-01-01

    Non-destructive measurements of contaminated soil core samples are desirable prior to destructive measurements because they allow obtaining gross information from the core samples without touching harmful chemical species. Medical X-ray computed tomography (CT) and time-domain low-field nuclear magnetic resonance (NMR) relaxometry were applied to non-destructive measurements of sandy soil core samples from a real site contaminated with heavy oil. The medical CT visualized the spatial distribution of the bulk density averaged over the voxel of 0.31 × 0.31 × 2 mm3. The obtained CT images clearly showed an increase in the bulk density with increasing depth. Coupled analysis with in situ time-domain reflectometry logging suggests that this increase is derived from an increase in the water volume fraction of soils with depth (i.e., unsaturated to saturated transition). This was confirmed by supplementary analysis using high-resolution micro-focus X-ray CT at a resolution of ∼10 μm, which directly imaged the increase in pore water with depth. NMR transverse relaxation waveforms of protons were acquired non-destructively at 2.7 MHz by the Carr–Purcell–Meiboom–Gill (CPMG) pulse sequence. The nature of viscous petroleum molecules having short transverse relaxation times (T2) compared to water molecules enabled us to distinguish the water-saturated portion from the oil-contaminated portion in the core sample using an M0–T2 plot, where M0 is the initial amplitude of the CPMG signal. The present study demonstrates that non-destructive core measurements by medical X-ray CT and low-field NMR provide information on the groundwater saturation level and oil-contaminated intervals, which is useful for constructing an adequate plan for subsequent destructive laboratory measurements of cores. PMID:21258437

  13. Nickel/carbon core/shell nanotubes: Lanthanum nickel alloy catalyzed synthesis, characterization and studies on their ferromagnetic and lithium-ion storage properties

    SciTech Connect

    Anthuvan Rajesh, John; Pandurangan, Arumugam; Senthil, Chenrayan; Sasidharan, Manickam

    2014-12-15

    Highlights: • Ni/CNTs core/shell structure was synthesized using LaNi{sub 5} alloy catalyst by CVD. • The magnetic and lithium-ion storage properties of Ni/CNTs structure were studied. • The specific Ni/CNTs structure shows strong ferromagnetic property with large coercivity value of 446.42 Oe. • Ni/CNTs structure shows enhanced electrochemical performance in terms of stable capacity and better rate capability. - Abstract: A method was developed to synthesize ferromagnetic nickel core/carbon shell nanotubes (Ni/CNTs) by chemical vapor deposition using Pauli paramagnetic lanthanum nickel (LaNi{sub 5}) alloy both as a catalyst and as a source for the Ni-core. The Ni-core was obtained through oxidative dissociation followed by hydrogen reduction during the catalytic growth of the CNTs. Transmission electron microscopy (TEM), selected area electron diffraction (SAED) and X-ray diffraction (XRD) analyses reveal that the Ni-core exists as a face centered cubic single crystal. The magnetic hysteresis loop of Ni/CNTs particle shows increased coercivity (446.42 Oe) than bulk Ni at room temperature. Furthermore, the Ni/CNTs core/shell particles were investigated as anode materials in lithium-ion batteries. The Ni/CNTs electrode delivered a high discharge capacity of 309 mA h g{sup −1} at 0.2 C, and a stable cycle-life, which is attributed to high structural stability of Ni/CNTs electrode during electrochemical lithium-ion insertion and de-insertion redox reactions.

  14. Coupling between core and cladding modes in a helical core fiber with large core offset

    NASA Astrophysics Data System (ADS)

    Napiorkowski, Maciej; Urbanczyk, Waclaw

    2016-05-01

    We analyzed the effect of resonant coupling between core and cladding modes in a helical core fiber with large core offset using the fully vectorial method based on the transformation optics formalism. Our study revealed that the resonant couplings to lower order cladding modes predicted by perturbative methods and observed experimentally in fibers with small core offsets are in fact prohibited for larger core offsets. This effect is related to the lack of phase matching caused by elongation of the optical path of the fundamental modes in the helical core. Moreover, strong couplings to the cladding modes of the azimuthal modal number much higher than predicted by perturbative methods may be observed for large core offsets, as the core offset introduces higher order angular harmonics in the field distribution of the fundamental modes. Finally, in contrast to previous studies, we demonstrate the existence of spectrally broad polarization sensitive couplings to the cladding modes suggesting that helical core fibers with large core offsets may be used as broadband circular polarizers.

  15. Integrated core-log petrofacies analysis in the construction of a reservoir geomodel: A case study of a mature Mississippian carbonate reservoir using limited data

    USGS Publications Warehouse

    Bhattacharya, S.; Doveton, J.H.; Carr, T.R.; Guy, W.R.; Gerlach, P.M.

    2005-01-01

    Small independent operators produce most of the Mississippian carbonate fields in the United States mid-continent, where a lack of integrated characterization studies precludes maximization of hydrocarbon recovery. This study uses integrative techniques to leverage extant data in an Osagian and Meramecian (Mississippian) cherty carbonate reservoir in Kansas. Available data include petrophysical logs of varying vintages, limited number of cores, and production histories from each well. A consistent set of assumptions were used to extract well-level porosity and initial saturations, from logs of different types and vintages, to build a geomodel. Lacking regularly recorded well shut-in pressures, an iterative technique, based on material balance formulations, was used to estimate average reservoir-pressure decline that matched available drillstem test data and validated log-analysis assumptions. Core plugs representing the principal reservoir petrofacies provide critical inputs for characterization and simulation studies. However, assigning plugs among multiple reservoir petrofacies is difficult in complex (carbonate) reservoirs. In a bottom-up approach, raw capillary pressure (Pc) data were plotted on the Super-Pickett plot, and log- and core-derived saturation-height distributions were reconciled to group plugs by facies, to identify core plugs representative of the principal reservoir facies, and to discriminate facies in the logged interval. Pc data from representative core plugs were used for effective pay evaluation to estimate water cut from completions, in infill and producing wells, and guide-selective perforations for economic exploitation of mature fields. The results from this study were used to drill 22 infill wells. Techniques demonstrated here can be applied in other fields and reservoirs. Copyright ?? 2005. The American Association of Petroleum Geologists. All rights reserved.

  16. The Nature of Fault Creep and Weakening in the San Andreas System Deduced from Studies of SAFOD Core (Invited)

    NASA Astrophysics Data System (ADS)

    Moore, D. E.; Rymer, M. J.; Lockner, D. A.

    2013-12-01

    Our understanding of the processes operative at depth in fault zones is severely hampered by the general inability to study the actively deforming fault rocks in situ. One of the main goals of the San Andreas Fault Observatory at Depth (SAFOD), a key component of Earthscope, was the recovery of core to allow petrographic, chemical, and physical examination of an active, plate-boundary fault at seismogenic depths, something that had never before been attempted. The SAFOD drill site is located 14 km northwest of Parkfield in central California, along a portion of the San Andreas Fault (SAF) that is characterized by a combination of aseismic slip and microseismicity. Innovations in the design and implementation of SAFOD (summarized in Zoback, Hickman and Ellsworth, Scientific Drilling, No. 11, March 2011) led to the identification of two actively creeping fault traces at 2.65 and 2.70 km vertical depth (~112°C). Subsequent multilateral coring operations successfully sampled the two zones of foliated gouge where creep is localized: the 2.6-m-wide central deforming zone (CDZ) and the 1.6-m-wide southwest deforming zone (SDZ). The two gouge zones are closely similar in character, consisting of porphyroclasts of serpentinite and sedimentary rock dispersed in a fine-grained, foliated matrix of Mg-rich smectitic clays (saponite × corrensite). The boundaries of the CDZ and SDZ with adjoining sedimentary rocks of the Great Valley Group are mineralogically, chemically, and texturally sharp. The Mg-rich clay minerals in the gouge zones are interpreted to be the product of fluid-assisted, shear-enhanced metasomatic reactions between the quartzofeldspathic wall rocks and serpentinite that was tectonically entrained in the SAF from a source in the Coast Range ophiolite. Laboratory friction tests indicate that gouge from the CDZ and SDZ deforms stably (i.e., creeps) at anomalously low levels of shear stress (coefficient of friction, μ ~ 0.15), which is sufficient to explain the

  17. Validation and application of a core set of patient-relevant outcome domains to assess the effectiveness of multimodal pain therapy (VAPAIN): a study protocol

    PubMed Central

    Kaiser, Ulrike; Kopkow, Christian; Deckert, Stefanie; Sabatowski, Rainer; Schmitt, Jochen

    2015-01-01

    Introduction Multimodal pain therapy (MPT) has been established accounting for biopsychosocial consideration in diagnostic and therapy. MPT seems to be effective, but comparability of studies is limited due to diversity of study designs and outcome measurements. The presented study aims to develop a core outcome set consisting of a minimum of outcome measures deemed necessary for medical and therapeutic decision-making, which must be measured in all clinical trials and non-randomised intervention studies. Methods and analysis The study consists of several parts. First, the development and recommendation of preliminary core outcome domains will be based on results of a systematic review and structured online surveys. Participants of the expert panel are representatives of methodological, medical, physiotherapeutic, psychotherapeutic profession and patients suffering from chronic pain (n=25). Subsequently, candidate instruments to measure preliminary core outcome domains will be recommended by these experts. Therefore, systematic reviews on measurement properties of preliminary outcome measures will be conducted and finalised in a consensus meeting. Consented instruments and lacking psychometric properties of relevant instruments will be addressed and validated in the following part, a prospective multicentre study in multimodal pain centres on approximately 300 patients with chronic pain. Based on all previous results, a core outcome set for MPT measured in effectiveness studies and daily recordkeeping will be finalised by consensus. Statistical analyses will be performed according to methodological standards (COSMIN). Ethics and dissemination The methods and procedure of the study are developed in compliance with the ethical principles of the Helsinki Declaration and Good Epidemiologic Practice. Recruitment of study participants will require approval of the study by the responsible ethics committee and signed informed consent from each participant. Pseudonymised

  18. The Seneca Babcock Business Plan: A Case Study in Using Service Learning to Meet the AICPA Core Competencies

    ERIC Educational Resources Information Center

    Tschopp, Daniel J.

    2004-01-01

    In this article, the author explains the trend toward service learning projects in higher education and justifies their use in the field of accounting. He describes a service learning project that was used to directly address the development of the competencies listed in the Core Competency Framework created by the American Institute of Certified…

  19. Enacting Common Core Instruction: A Comparative Study of the Use of LDC Literacy Tools in Three Sites

    ERIC Educational Resources Information Center

    Beaver, Jessica K.; Reumann-Moore, Rebecca

    2014-01-01

    As of the writing of this report, the Common Core State Standards (CCSS) are being implemented in 45 states and the District of Columbia. Approaches to implementing the standards, however, are highly varied. For the past 3 years, Research For Action (RFA) has been tracking how one approach to implementing the literacy standards--the Literacy…

  20. In Opposition to Core Curriculum. Alternative Models for Undergraduate Education. Contributions to the Study of Education, Number 4.

    ERIC Educational Resources Information Center

    Hall, James W., Ed.; Kevles, Barbara L., Ed.

    In response to some educators' advocacy of a return to a "core curriculum" (a specific set of courses required by all degree-bound college students), this book maintains that the simple acquisition of broad-based knowledge is not the solution to the complex and difficult problems in higher education today. It presents views of the "educated…

  1. A three-phase three-winding core-type transformer model for low-frequency transient studies

    SciTech Connect

    Chen, X.; Venkata, S.S.

    1997-04-01

    A topology-based and duality-derived three-phase, three-winding, core-type transformer model is presented. The model treats the leakage inductances and the coupling effects of the core in a straightforward and integrated way. The long-established positive- and zero-sequence star equivalent circuits of a three-phase three-winding transformer are derived from the original equivalent magnetic circuit of the transformer by applying duality. Formulations for determining the values of the leakage inductances and the core loss resistances from transformer open- and short-circuit test data are presented. A supporting routine is written to generate the {lambda}-i curves for each segment of the core and the other input data for EMTP. Since the duality-derived model consists of only RLC elements, no device-specific code to EMTP time-step code is needed. Winding capacitances are lumped to the terminals. The model is suitable for simulation of power system low-frequency transients such as inrush currents and ferroresonance, short circuits, and abnormalities including transformer winding faults.

  2. Dynamic studies of {sup 11}Li and its core {sup 9}Li on {sup 208}Pb near the Coulomb barrier

    SciTech Connect

    Cubero, M.; Borge, M. J. G.; Alcorta, M.; Madurga, M.; Tengblad, O.; Acosta, L.; Martel, I.; Sanchez-Benitez, A. M.; Alvarez, M. A. G.; Gomez-Camacho, J.; Diget, C.; Galaviz, D.; Fernandez-Garcia, J. P.; Lay, J. A.; Moro, A. M.; Mukha, I.; Shotter, A.; Walden, P.

    2010-04-26

    We measured the scattering of the halo nucleus {sup 11}Li and its core {sup 9}Li on the lead target at TRIUMF at energies below and around to the Coulomb barrier. We report here on our preliminary analysis of the inclusive breakup reaction.

  3. Parameter Sensitivity Study of the Unreacted-Core Shrinking Model: A Computer Activity for Chemical Reaction Engineering Courses

    ERIC Educational Resources Information Center

    Tudela, Ignacio; Bonete, Pedro; Fullana, Andres; Conesa, Juan Antonio

    2011-01-01

    The unreacted-core shrinking (UCS) model is employed to characterize fluid-particle reactions that are important in industry and research. An approach to understand the UCS model by numerical methods is presented, which helps the visualization of the influence of the variables that control the overall heterogeneous process. Use of this approach in…

  4. DUST CONTINUUM AND POLARIZATION FROM ENVELOPE TO CORES IN STAR FORMATION: A CASE STUDY IN THE W51 NORTH REGION

    SciTech Connect

    Tang, Ya-Wen; Guilloteau, Stephane; Dutrey, Anne; Ho, Paul T. P.; Koch, Patrick M.

    2013-02-15

    We present the first high-angular resolution (up to 0.''7, {approx}5000 AU) polarization and thermal dust continuum images toward the massive star-forming region W51 North. The observations were carried out with the Submillimeter Array (SMA) in both the subcompact (SMA-SubC) and extended (SMA-Ext) configurations at a wavelength of 870 {mu}m. W51 North is resolved into four cores (SMA1 to SMA4) in the 870 {mu}m continuum image. The associated dust polarization exhibits more complex structures than seen at lower angular resolution. We analyze the inferred morphologies of the plane-of-sky magnetic field (B ) in the SMA1 to SMA4 cores and in the envelope using the SMA-Ext and SMA-SubC data. These results are compared with the B archive images obtained from the Caltech Submillimeter Observatory (CSO) and James Clerk Maxwell Telescope (JCMT). The polarization percentage is about 1% to 4%, and it is found to decrease with higher intensity in our SMA images, which is a similar trend to that previously reported in the CSO and JCMT data. A correlation between dust intensity gradient position angles ({phi}{sub {nabla}I}) and magnetic field position angles ({phi}{sub B}) is found in the CSO, JCMT, and both SMA data sets. This correlation is further analyzed quantitatively. A systematically tighter correlation between {phi}{sub {nabla}I} and {phi}{sub B} is found in the cores, whereas the correlation decreases in outside-core regions. Magnetic field-to-gravity force ratio ({Sigma}{sub B}) maps are derived using the newly developed polarization-intensity gradient method by Koch et al. We find that the force ratios tend to be small ({Sigma}{sub B} {approx}< 0.5) in the cores in all four data sets. In regions outside of the cores, the ratios increase or the field is even dominating gravity ({Sigma}{sub B} > 1). This possibly provides a physical explanation of the tightening correlation between {phi}{sub {nabla}I} and {phi}{sub B} in the cores: The more the B field lines are

  5. Axisymmetric collapse simulations of rotating massive stellar cores in full general relativity: Numerical study for prompt black hole formation

    SciTech Connect

    Sekiguchi, Yu-ichirou; Shibata, Masaru

    2005-04-15

    We perform axisymmetric simulations for gravitational collapse of a massive iron core to a black hole in full general relativity. The iron cores are modeled by {gamma}=4/3 equilibrium polytrope for simplicity. The hydrodynamic equations are solved using a high-resolution shock-capturing scheme with a parametric equation of state. The Cartoon method is adopted for solving the Einstein equations. Simulations are performed for a wide variety of initial conditions changing the mass ({approx_equal}2.0-3.0M{sub {center_dot}}), the angular momentum, the rotational velocity profile of the core, and the parameters of the equations of state which are chosen so that the maximum mass of the cold spherical polytrope is {approx_equal}1.6M{sub {center_dot}}. Then, the criterion for the prompt black hole formation is clarified in terms of the mass and the angular momentum for several rotational velocity profile of the core and equations of state. It is found that (i) with the increase of the thermal energy generated by shocks, the threshold mass for the prompt black hole formation is increased by 20-40%, (ii) the rotational centrifugal force increases the threshold mass by < or approx. 25%, (iii) with the increase of the degree of differential rotation, the threshold mass is also increased, and (iv) the amplification factors shown in the results (i)-(iii) depend sensitively on the equation of state. We also find that the collapse dynamics and the structure of the shock formed at the bounce depend strongly on the stiffness of the adopted equation of state. In particular, as a new feature, a strong bipolar explosion is observed for the collapse of rapidly rotating iron cores with an equation of state which is stiff in subnuclear density and soft in supranuclear density. Gravitational waves are computed in terms of a quadrupole formula. It is also found that the waveform depends sensitively on the equations of state.

  6. Clinical evaluation of carbon fiber reinforced carbon endodontic post, glass fiber reinforced post with cast post and core: A one year comparative clinical study

    PubMed Central

    Preethi, GA; Kala, M

    2008-01-01

    Aim: Restoring endodontically treated teeth is one of the major treatments provided by the dental practitioner. Selection and proper use of restorative materials continues to be a source of frustration for many clinicians. There is controversy surrounding the most suitable choice of restorative material and the placement method that will result in the highest probability of successful treatment. This clinical study compares two different varieties of fiber posts and one cast post and core in terms of mobility of crown margin under finger pressure, recurrent caries detected at the crown margin, fracture of the restoration, fracture of the root and periapical and periodontal pathology requiring crown removal over the period of 12months as evaluated by clinical and radiographical examination. Materials and Methods: 30 root canal treated, single rooted maxillary anterior teeth of 25 patients in the age range of 18–60 years where a post retained crown was indicated were selected for the study between January 2007 and August 2007; and prepared in a standard clinical manner. It was divided into 3 groups of 10 teeth in each group. After post space preparation, the Carbon fiber and Glass fiber reinforced posts were cemented with Scotch bond multipurpose plus bonding agent and RelyX adhesive resin cement in the first and second groups respectively. The Cast post and cores were cemented with Zinc Phosphate cement in the third group. Following post- cementation, the preparation was further refined and a rubber base impression was taken for metal-ceramic crowns which was cemented with Zinc Phosphate cement. A baseline periapical radiograph was taken once each crown was cemented. All patients were evaluated after one week (baseline), 3 months, 6 months and one year for following characteristics mobility of crown margin under finger pressure, recurrent caries detected at the crown margin, fracture of the restoration, fracture of the root and periapical and periodontal pathology

  7. The ADNI PET Core

    PubMed Central

    Jagust, William J.; Bandy, Dan; Chen, Kewei; Foster, Norman L.; Landau, Susan M.; Mathis, Chester A.; Price, Julie C.; Reiman, Eric M.; Skovronsky, Daniel; Koeppe, Robert A.

    2010-01-01

    Background This is a progress report of the Alzheimer's Disease Neuroimaging Initiative (ADNI) PET Core. Methods The Core has supervised the acquisition, quality control, and analysis of longitudinal [18F]fluorodeoxyglucose PET (FDG-PET) data in approximately half of the ADNI cohort. In an “add on” study, approximately 100 subjects also underwent scanning with [11C]PIB-PET for amyloid imaging. The Core developed quality control procedures and standardized image acquisition by developing an imaging protocol that has been widely adopted in academic and pharmaceutical industry studies. Data processing provides users with scans that have identical orientation and resolution characteristics despite acquisition on multiple scanner models. The Core labs have used a number of different approaches to characterize differences between subject groups (AD, MCI, controls), to examine longitudinal change over time in glucose metabolism and amyloid deposition, and to assess the use of FDG-PET as a potential outcome measure in clinical trials. Results ADNI data indicate that FDG-PET increases statistical power over traditional cognitive measures, might aid subject selection, and could substantially reduce the sample size in a clinical trial. PIB-PET data showed expected group differences, and identified subjects with significant annual increases in amyloid load across the subject groups. The next activities of the PET core in ADNI will entail developing standardized protocols for amyloid imaging using the [18F]-labeled amyloid imaging agent AV45, which can be delivered to virtually all ADNI sites. Conclusions ADNI has demonstrated the feasibility and utility of multicenter PET studies and is helping to clarify the role of biomarkers in the study of aging and dementia. PMID:20451870

  8. Two-Dimensional Cutting (TDC) Vitrectome: In Vitro Flow Assessment and Prospective Clinical Study Evaluating Core Vitrectomy Efficiency versus Standard Vitrectome.

    PubMed

    Pavlidis, Mitrofanis

    2016-01-01

    Purpose. To evaluate comparative aspiration flow performance and also vitrectomy operating time efficiency using a double-cutting open port vitreous cutting system incorporated in a two-dimensional cutting (TDC, DORC International) vitrectome design versus standard vitreous cutter. Methods. In vitro investigations compared aspiration flow rates in artificial vitreous humor at varying cutter speeds and vacuum levels using a TDC vitrectome and a standard vitrectome across different aspiration pump systems. A prospective single-centre clinical study evaluated duration of core vitrectomy in 80 patients with macular pucker undergoing 25-gauge or 27-gauge vitrectomy using either a TDC vitrectome at 16,000 cuts per minute (cpm) or standard single-cut vitrectome, combined with a Valve Timing intelligence (VTi) pump system (EVA, DORC International). Results. Aspiration flow rates remained constant independent of TDC vitrectome cut rate, while flow rates decreased linearly at higher cutter speeds using a classic single-blade vitrectome. Mean duration of core vitrectomy surgeries using a TDC vitreous cutter system was significantly (p < 0.001) shorter than the mean duration of core vitrectomy procedures using a single-cut vitrectome of the same diameter (reduction range, 34%-50%). Conclusion. Vitrectomy surgery performed using a TDC vitrectome was faster than core vitrectomy utilizing a standard single-action vitrectome at similar cut speeds. PMID:27190635

  9. Two-Dimensional Cutting (TDC) Vitrectome: In Vitro Flow Assessment and Prospective Clinical Study Evaluating Core Vitrectomy Efficiency versus Standard Vitrectome

    PubMed Central

    2016-01-01

    Purpose. To evaluate comparative aspiration flow performance and also vitrectomy operating time efficiency using a double-cutting open port vitreous cutting system incorporated in a two-dimensional cutting (TDC, DORC International) vitrectome design versus standard vitreous cutter. Methods. In vitro investigations compared aspiration flow rates in artificial vitreous humor at varying cutter speeds and vacuum levels using a TDC vitrectome and a standard vitrectome across different aspiration pump systems. A prospective single-centre clinical study evaluated duration of core vitrectomy in 80 patients with macular pucker undergoing 25-gauge or 27-gauge vitrectomy using either a TDC vitrectome at 16,000 cuts per minute (cpm) or standard single-cut vitrectome, combined with a Valve Timing intelligence (VTi) pump system (EVA, DORC International). Results. Aspiration flow rates remained constant independent of TDC vitrectome cut rate, while flow rates decreased linearly at higher cutter speeds using a classic single-blade vitrectome. Mean duration of core vitrectomy surgeries using a TDC vitreous cutter system was significantly (p < 0.001) shorter than the mean duration of core vitrectomy procedures using a single-cut vitrectome of the same diameter (reduction range, 34%–50%). Conclusion. Vitrectomy surgery performed using a TDC vitrectome was faster than core vitrectomy utilizing a standard single-action vitrectome at similar cut speeds. PMID:27190635

  10. The influence of the root cross-section on the stress distribution in teeth restored with a positive-locking post and core design: a finite element study.

    PubMed

    Schilling, Kai-Uwe; Rottner, Kurt; Boldt, Julian; Proff, Peter; Gredes, Tomasz; Richter, Ernst-Jürgen; Reicheneder, Claudia

    2008-10-01

    Human teeth with substantial coronal defects are subject to reconstruction by means of post and core restorations. Typically, such a restoration comprises a slightly cylindrical post onto which an abutment of varying shape, depending on the designated restoration, is attached. As clinical results are not satisfactory to date, we proposed a new proprietary post and core design which makes use of positive locking. As this prefabricated system is not customised to an individual root's cross-sectional geometry (usually oval), a varying amount of radicular dentin is left in periphery of the core's outer edge. The aim of this study was to assess the implications of this fact, i.e., whether the root has to endure higher overall stress levels which ultimately may lead to failure of one of the components involved. A series of finite element simulations were performed to evaluate stress and strain on the system, in which the proposed post and core was embedded into a virtual dentin cylinder of different diameters, ranging from flush mounting of the restoration to a dentin excess of 4 mm, and subsequently loaded with forces with two angles of attack (90 degrees and 130 degrees ). The results show that flush mounting yields an agreeable stress and strain distribution within the radicular dentin, but overall stress levels drop significantly with an excess of 0.5 mm of surrounding dentin. More than 1 mm excess was not found to have profound positive effects. PMID:18803526

  11. Comparative study on a core-offset fiber temperature sensor between the faraday rotation mirror structure and the double coupling structure

    NASA Astrophysics Data System (ADS)

    Wang, Fang; Zhu, Han; Li, Yunpeng; Zhao, Huihui; Wang, Xu; Liu, Yufang

    2016-05-01

    A temperature sensor based on core-offset single mode fiber (SMF) and a Faraday rotation mirror (FRM) has been proposed and experimentally demonstrated in this paper. This sensor was fabricated by splicing in a section of SMF between two SMFs with a core-offset at two splicing joints. The end of the joint is connected to the FRM, which can double the sensitivity and improve the polarization state stabilization at the sensor output. The variation of the transmission spectrum of the sensor with respect to the surrounding temperature has been experimentally studied. A comparison is made between this design and a laser temperature sensor made of the same core-offset fiber utilizing a double coupling (DC) structure. The results show that, within the range of 1539.42-1553.90 nm, the sensitivity of the proposed sensor is 0.89039 nm/°C and in the range of 47-63 °C. Additionally, the power attenuation is 2.257 dB/°C. The temperature sensitivity in the SMF and FRM sensor is increased by an order of magnitude in comparison with the DC sensor. The instability and low sensitivity characteristics of a laser temperature sensor constructed with DC structure can be solved through the use of core-offset SMF and FRM.

  12. Exploring the structural and magnetic properties of TiO{sub 2}/SnO{sub 2} core/shell nanocomposite: An experimental and density functional study

    SciTech Connect

    Chetri, Pawan; Basyach, Priyanka; Choudhury, Amarjyoti

    2014-12-15

    TiO{sub 2}/SnO{sub 2} core/shell nanocomposite is prepared via a simple sol–gel method and the properties are compared with the individual TiO{sub 2} (core) and SnO{sub 2} (shell). The corresponding characterizations are carried out in terms of structural and magnetic properties of TiO{sub 2}/SnO{sub 2}, TiO{sub 2} and SnO{sub 2} nanosystems. Structural properties are studied via XRD, TEM, Raman spectroscopy, FTIR and XPS. Magnetic characterization is performed by measuring Moment vs. Applied Field for all the samples and Moment vs. Temperature for TiO{sub 2}/SnO{sub 2} core/shell nanocomposite. We also went for a better insight with the help of theoretical measures. First principle calculations have been executed using “Density Functional Theory” (DFT)-based MedeA VASP package to compare the results of TiO{sub 2}/SnO{sub 2} with TiO{sub 2} (1 1 0) and SnO{sub 2} (1 1 0) surface calculations and its effect on the magnetic nature of the specific nanoparticles. XRD, RAMAN and FTIR gave indirect evidence of formation of core shell nanostructure while TEM micrographs provide the direct evidence of formation of core shell nanostructure. The magnetic study shows a higher saturation magnetization for the core/shell nanostructure compared to pristine TiO{sub 2} and SnO{sub 2}. In this report, we have attempted to relate this experimental observation with the results of the first principle calculations. - Graphical abstract: Above pictorial presentation (from left) represents the model for TS, TiO{sub 2} and SnO{sub 2} used for DFT calculation and the obtained magnetic results for all the prepared systems. - Highlights: • Synthesis of TiO{sub 2}/SnO{sub 2} core/shell nanocomposites by a simple sol–gel technique. • The nanocomposites show better magnetic property than pristine nanoparticles. • DFT based calculations also support the experimental evidences.

  13. Association of Mutations in the Basal Core Promoter and Pre-core Regions of the Hepatitis B Viral Genome and Longitudinal Changes in HBV Level in HBeAg Negative Individuals: Results From a Cohort Study in Northern Iran

    PubMed Central

    Besharat, Sima; Poustchi, Hossein; Mohamadkhani, Ashraf; Katoonizadeh, Aezam; Moradi, Abdolvahab; Roshandel, Gholamreza; Freedman, Neal David; Malekzadeh, Reza

    2015-01-01

    Background: Although certain HBV mutations are known to affect the expression of Hepatitis e antigen, their association with HBV viral level or clinical outcomes is less clear. Objectives: We evaluated associations between different mutations in the Basal Core promoter (BCP) and Pre-core (PC) regions of HBV genome and subsequent changes in HBV viral DNA level over seven years in a population of untreated HBeAg negative chronic hepatitis B (CHB) participants in Northeast of Iran. Materials and Methods: Participants in the current study were drawn from the Golestan Hepatitis B Cohort Study (GHBCS), a cohort of approximately 2590 HBsAg positive subjects (living in Gonbad city) embedded in the Golestan Cohort Study (GCS). At baseline, HBsAg was measured in all participants and revealed 2590 HBsAg positive cases. We randomly selected 304 participants who their blood sample were taken at both baseline and seven years later in follow-up and had not been treated for HBV during this time. HBV viral load were assessed at baseline and at year 7. The BCP and PC regions of the HBV DNA, at baseline, were amplified via hemi-nested PCR and sequenced by cycle sequencing. At year 7, liver stiffness was assessed by fibroscan; also, other parameters of liver disease were assessed following standard clinical protocols. Associations were assessed via tabulation, chi-square, t-tests and logistic regression. P values < 0.05 were considered statistically significant and all tests were two-sided. Results: Among 304 HBsAg positive participants, 99 had detectable HBV DNA at study baseline. Of these, 61.6% had PC mutations (48.5% A1896 and 25.2% G1899). In contrast to other mutations, A1896 was associated with a higher proportion of detectable HBV DNA at year 7 (39.6%) compared to patients with the wild type (13.7%) (OR: 4.36, CI95% = 1.63-11.70; P Value = 0.002). Although participants with the A1896 mutation had higher year-7 HBV viral load than participants with G1896 (2.30 ± 1.66 IU/mL vs

  14. Ab initio study of 3s core-level x-ray photoemission spectra in transition metals

    NASA Astrophysics Data System (ADS)

    Takahashi, Manabu; Igarashi, Jun-Ichi

    2010-01-01

    We calculate the 3s - and 4s -core-level x-ray photoemission spectroscopy (XPS) spectra in the ferromagnetic and nonmagnetic transition metals by developing an ab initio method. We obtain the spectra exhibiting the characteristic shapes as a function of binding energy in good agreement with experimental observations. The spectral shapes are strikingly different between the majority spin channel and the minority spin channel for ferromagnetic metals Ni, Co, and Fe, that is, large intensities appear in the higher binding-energy side of the main peak (satellite) in the majority spin channel. Such satellite or shoulder intensities are also obtained for nonmagnetic metals V and Ru. These behaviors are elucidated in terms of the change of the one-electron states induced by the core-hole potential.

  15. Kinetic analysis of data obtained from studies on microbial degradation of cement waste forms, using shrinking core models.

    PubMed

    Idachaba, M A; Nyavor, K; Egiebor, N O

    2003-04-01

    Model equations based on analytical solutions of two shrinking core models (acid dissolution or shrinking unreacted core (SUC) model, and bulk diffusion model), were used to analyze the kinetics of microbial degradation of cement waste forms. Two current approaches of waste form microbial stability evaluation (Nuclear Regulatory Commission (NRC) method and refined biofilm formation) were used to generate the data. Good linear correlations with R(2)>0.95 were obtained for the leaching data from both the NRC and biofilm approaches, using the model equation based on the bulk diffusion concept. Analyses using the model equation based on the acid dissolution model generally gave poor correlations except when data obtained from biofilm formation method was normalized. PMID:12686024

  16. The Comparative Study of Paleoenvironmental Proxies from 3 Sediment Cores Sampled from Lake Erie at 1988, 1991 and 2003

    NASA Astrophysics Data System (ADS)

    Lu, Y.; Meyers, P. A.; Brian, E. J.; Robbins, J. A.

    2006-05-01

    The oxygen isotopic composition of calcium carbonate in hardwater lakes reflect the impacts from meteorological factors whereas the carbon and nitrogen isotopes indicate the changes of biological productivity in the lake. However, the fidelity of these proxies in recording paleoenvironment information can be biased by the post-deposition diagenesis. We have compared the isotopic contents and the mass accumulation rates of organic carbon and calcium carbonate in sediment cores collected in 1988, 1991, and 2003 from the same location in Lake Erie to each other and to meteorological records beginning in 1895. Eutrophication accelerated calcite dissolution, but isotopic proxies are preserved. The comparison of paleoenvironmental histories concurrently interpreted from the there cores has provided interesting insights into early diagenesis, carbon dynamics and past depositional environments in Lake Erie. The geochemical proxies also reflect significant impacts from twentieth century urbanization.

  17. Black-Scholes-Schrödinger-Zipf-Mandelbrot model framework for improving a study of the coauthor core score

    NASA Astrophysics Data System (ADS)

    Rotundo, Giulia

    2014-06-01

    The data and findings by Miskiewicz (2013) on the relationship between the number (J) of publications ranked according to their decreasing importance, for some scientist with her/his coauthors (CA), i.e. J∝1/rα, as found in Ausloos (2013), when specific types of publications, i.e. proceedings (in a generalized sense) and peer-review journals, are considered, are reexamined along the Zipf-Mandelbrot law Mandelbrot (1977), i.e. J∝1/(. The statistics are much improved. The exponent α and ζ are compared. The ma core value, i.e. the core number of CAs [1] is unaffected, of course. A Black-Scholes-Schrödinger model framework is proposed to describe the findings.

  18. Valence photoionization and resonant core excitation of ozone - experimental and theoretical study of the C˜-state of O 3+

    NASA Astrophysics Data System (ADS)

    Wiesner, K.; Fink, R. F.; Sorensen, S. L.; Andersson, M.; Feifel, R.; Hjelte, I.; Miron, C.; Naves de Brito, A.; Rosenqvist, L.; Wang, H.; Svensson, S.; Björneholm, O.

    2003-06-01

    Resonant Auger electron spectra of core excited O 3 ( OT1s -12b 11) are presented for the first time. The photoionization valence spectrum with sample purity and resolution superior to those published is presented. The first direct experimental evidence for the C˜ 2 B 1 state of O 3+ is found. Ab initio calculations of the resonant Auger electron (RAE) spectrum have been performed supporting the assignment of the C˜-state.

  19. Thermosensitive core-shell particles as model systems for studying the flow behavior of concentrated colloidal dispersions.

    PubMed

    Crassous, J J; Siebenbürger, M; Ballauff, M; Drechsler, M; Henrich, O; Fuchs, M

    2006-11-28

    We report on a comprehensive investigation of the flow behavior of colloidal thermosensitive core-shell particles at high densities. The particles consist of a solid core of poly(styrene) onto which a network of cross-linked poly(N-isopropylacrylamide) is affixed. Immersed in water the shell of these particles will swell if the temperature is low. Raising the temperature above 32 degrees C leads to a volume transition within this shell which leads to a marked shrinking of the shell. The particles have well-defined core-shell structure and a narrow size distribution. The remaining electrostatic interactions due to a small number of charges affixed to the core particles can be screened by adding 0.05M KCl to the suspensions. Below the lower critical solution temperature at 32 degrees C the particles are purely repulsive. Above this transition, a thermoreversible coagulation takes place. Lowering the temperature again leads to full dissociation of the aggregates formed by this process. The particles crystallize for effective volume fractions between 0.48 and 0.55. The crystallites can be molten by shear in order to reach a fluid sample again. The reduced shear stress measured in this metastable disordered state was found to be a unique function of the shear rate and the effective volume fraction. These reduced flow curves thus obtained can be described quantitatively by the theory of Fuchs and Cates [Phys. Rev. Lett. 89, 248304 (2002)] which is based on the mode-coupling theory of the glass transition. PMID:17144739

  20. Time resolved photoluminescence study of CdSe/CdMnS/CdS core/shell/shell nanoplatelets heterostructures

    NASA Astrophysics Data System (ADS)

    Scrace, Thomas; Delikanli, Savas; Akgul, Mehmet Zafer; Murphy, Joseph; Thomay, Tim; Zhang, Peiyao; Norden, Tenzin; Cartwright, Alexander; Petrou, Athos; Demir, Hilmi Volkan

    We have recorded the time evolution of the photoluminescence (PL) for CdSe/CdMnS/CdS core/shell/shell solution-processed nanoplatelets (NP) using ultrafast pulses at 400 nm and 514 nm. Our NPs consist of a core with 5 monolayers (1.5 nm) of CdSe and average lateral dimensions of 55 x 10 nm2. Using 400 nm pulses we excite electron-hole pairs above the CdS shell bandgap; with 514 nm pulses we excite only in the CdSe core. The holes are primarily localized in the CdSe core, while the electrons are delocalized. Our measurements show that at Δt = 0, the peak PL energy for both kind of excitations is the same. As a function of time, both types of excitations result in a red-shift. The red shift of with 400 nm excitation is 60 meV and is described by two time scales: τ1 = 270 ps and τ2 = 2.5 ns. The red shift with the 514 nm excitation is 30 meV and is described by a single time scale: τ2' = 2.5 ns. These results are discussed in terms of dipole layer formation. H.V.D. is supported by EU-FP7 Nanophotonics4Energy NoE, and TUBITAK EEEAG 109E002, 109E004, NRF-RF-2009-09, NRF-CRP-6-2010-02 and A*STAR of Singapore. A.P. is supported by NSF DMR 1305770.

  1. Verification study of thorium cross section in MVP calculation of thorium based fuel core using experimental data

    SciTech Connect

    Mai, V. T.; Fujii, T.; Wada, K.; Kitada, T.; Takaki, N.; Yamaguchi, A.; Watanabe, H.; Unesaki, H.

    2012-07-01

    Considering the importance of thorium data and concerning about the accuracy of Th-232 cross section library, a series of experiments of thorium critical core carried out at KUCA facility of Kyoto Univ. Research Reactor Inst. have been analyzed. The core was composed of pure thorium plates and 93% enriched uranium plates, solid polyethylene moderator with hydro to U-235 ratio of 140 and Th-232 to U-235 ratio of 15.2. Calculations of the effective multiplication factor, control rod worth, reactivity worth of Th plates have been conducted by MVP code using JENDL-4.0 library [1]. At the experiment site, after achieving the critical state with 51 fuel rods inserted inside the reactor, the measurements of the reactivity worth of control rod and thorium sample are carried out. By comparing with the experimental data, the calculation overestimates the effective multiplication factor about 0.90%. Reactivity worth of the control rods evaluation using MVP is acceptable with the maximum discrepancy about the statistical error of the measured data. The calculated results agree to the measurement ones within the difference range of 3.1% for the reactivity worth of one Th plate. From this investigation, further experiments and research on Th-232 cross section library need to be conducted to provide more reliable data for thorium based fuel core design and safety calculation. (authors)

  2. Dielectric and electro-optic studies of a bimesogenic liquid crystal composed of bent-core and calamitic units.

    PubMed

    Balachandran, R; Panov, V P; Vij, J K; Shanker, G; Tschierske, C; Merkel, K; Kocot, A

    2014-09-01

    A bimesogen, BR1, composed of a bent-core and calamitic unit, linked laterally via a flexible spacer is investigated by dielectric and electro-optic techniques. X-ray results show the presence of clusters in the nematic phase, and the cluster size is of the order of the thickness of a single layer. The splitting of the small-angle scattering Δχ/2 is about 50°, which indicates SmC like clusters with a significant tilt of the molecules in the quasilayers. The sign reversal of the dielectric anisotropy Δε' is observed as a function of frequency; the behavior is rather similar to that exhibited by the conventional dual frequency nematics, composed of a calamitic mesogen, with the exception that it occurs at much lower frequencies in this material. Interestingly, as the bimesogen enters its nematic phase, the average permittivity decreases as the temperature is lowered. This indicates the onset of antiparallel association of some of the dipoles in the system, and this type of association is much more prominent in BR1 in comparison to other bent-core liquid crystalline systems composed of the same bisbenzoate core unit. The analysis of the dielectric spectra using the Maier-Meier model confirms the onset of an antiparallel correlation of dipoles occurring at the isotropic to nematic phase transition temperature. Additionally these results support a model of the cluster where the transverse dipole moments in the neighboring layers are antiparalleled to each other. PMID:25314464

  3. Structure is three to ten times more conserved than sequence--a study of structural response in protein cores.

    PubMed

    Illergård, Kristoffer; Ardell, David H; Elofsson, Arne

    2009-11-15

    Protein structures change during evolution in response to mutations. Here, we analyze the mapping between sequence and structure in a set of structurally aligned protein domains. To avoid artifacts, we restricted our attention only to the core components of these structures. We found that on average, using different measures of structural change, protein cores evolve linearly with evolutionary distance (amino acid substitutions per site). This is true irrespective of which measure of structural change we used, whether RMSD or discrete structural descriptors for secondary structure, accessibility, or contacts. This linear response allows us to quantify the claim that structure is more conserved than sequence. Using structural alphabets of similar cardinality to the sequence alphabet, structural cores evolve three to ten times slower than sequences. Although we observed an average linear response, we found a wide variance. Different domain families varied fivefold in structural response to evolution. An attempt to categorically analyze this variance among subgroups by structural and functional category revealed only one statistically significant trend. This trend can be explained by the fact that beta-sheets change faster than alpha-helices, most likely due to that they are shorter and that change occurs at the ends of the secondary structure elements. PMID:19507241

  4. Hollow nitrogen-containing core/shell fibrous carbon nanomaterials as support to platinum nanocatalysts and their TEM tomography study

    NASA Astrophysics Data System (ADS)

    Zhou, Cuifeng; Liu, Zongwen; Du, Xusheng; Mitchell, David Richard Graham; Mai, Yiu-Wing; Yan, Yushan; Ringer, Simon

    2012-03-01

    Core/shell nanostructured carbon materials with carbon nanofiber (CNF) as the core and a nitrogen (N)-doped graphitic layer as the shell were synthesized by pyrolysis of CNF/polyaniline (CNF/PANI) composites prepared by in situ polymerization of aniline on CNFs. High-resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared and Raman analyses indicated that the PANI shell was carbonized at 900°C. Platinum (Pt) nanoparticles were reduced by formic acid with catalyst supports. Compared to the untreated CNF/PANI composites, the carbonized composites were proven to be better supporting materials for the Pt nanocatalysts and showed superior performance as catalyst supports for methanol electrochemical oxidation. The current density of methanol oxidation on the catalyst with the core/shell nanostructured carbon materials is approximately seven times of that on the catalyst with CNF/PANI support. TEM tomography revealed that some Pt nanoparticles were embedded in the PANI shells of the CNF/PANI composites, which might decrease the electrocatalyst activity. TEM-energy dispersive spectroscopy mapping confirmed that the Pt nanoparticles in the inner tube of N-doped hollow CNFs could be accessed by the Nafion ionomer electrolyte, contributing to the catalytic oxidation of methanol.

  5. Study on preparation of the core-nanoshell composite absorbers by high-energy ball milling at room temperature.

    PubMed

    Che, Ruxin; Gao, Hong; Yu, Bing; Wang, Shuo; Wang, Chunxia

    2012-02-01

    Electromagnetic (EM) wave pollution has become the chief physical pollution for environment. In recent years, some researches have been focused on the preparation of nano-composite absorbers at low temperatures or even at room temperature. In this letter, preparation of nanocomposite by using high-energy ball milling at room temperature is reported. The core-nanoshell composite absorbers with magnetic fly-ash hollow cenosphere (MFHC) as nuclear and nanocrystalline magnetic material as shell were prepared by high-energy ball milling and vacuum-sintering in this paper. The pre-treatment of MFHC, the sintering process and the mol ratio of starting chemicals had a significant impact for property of composite absorbers. The results of X-ray diffraction analysis (XRD), transmission electron microscope (TEM), vibrating sample magnetometer (VSM) and vector network analyzer (VNA) analysis indicated that perfect-crystalline nanomagnetic material coating was gotten with a particle size of 12 nm after ball milling. The results show the MFHC is dielectric loss and magnetic loss too; the exchange-coupling interaction happened between ferrite of the MFHC and nanocrystalline magnetic material coating. The exchange-coupling interaction enhances magnetic loss of composite absorbers. They have a perfect EM parameters at low microwave frequency. The core-nanoshell composite absorbers have a higher magnetic loss at low frequencies, and it is consistent with requirements of the microwave absorbing material at the low-frequency absorption. The microwave absorptivity of the core-nanoshell composite absorbers is better than single material. PMID:22630008

  6. Prediction of posttraumatic femoral head osteonecrosis by quantitative intraosseous aspirate and core biopsy analysis: a prospective study.

    PubMed

    Sen, Ramesh Kumar; Tripathy, Sujit Kumar; Gill, Shivinder Singh; Verma, Neelam; Singh, Paramjeet; Radotra, Bishan Dass

    2010-08-01

    Twenty-two patients with unreduced hip dislocation or fracture dislocation were prospectively evaluated. Intraosseous aspiration, marrow fluid analysis and core biopsy histological analysis was performed from the supero-lateral (test group) and central part (control group) of the femoral head. After appropriate surgical treatment and postoperative management, they were followed up for 2 years by clinical, radiological and magnetic resonance imaging evaluation. Eight patients eventually developed avascular necrosis (AVN) of the femoral head. The analysis of test samples revealed that 9 patients had an aspirate volume of < 1 cc ; marrow morphology of 11 hips showed necrotic cells; 12 patients had a core biopsy histology suggestive of dead osseous fragments and necrotic osteocytes. In contrast, all the control samples had an aspirate volume of > 1cc and showed viable cells on histology. Intra-operative assessment of marrow-aspirate volume (< 1cc), marrow morphology and core biopsy histology from the superolateral part of femur head can fairly predict the development of subsequent ONFH after trauma; the correlation is statistically significant (p < 0.05). PMID:20973355

  7. Hollow nitrogen-containing core/shell fibrous carbon nanomaterials as support to platinum nanocatalysts and their TEM tomography study

    PubMed Central

    2012-01-01

    Core/shell nanostructured carbon materials with carbon nanofiber (CNF) as the core and a nitrogen (N)-doped graphitic layer as the shell were synthesized by pyrolysis of CNF/polyaniline (CNF/PANI) composites prepared by in situ polymerization of aniline on CNFs. High-resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared and Raman analyses indicated that the PANI shell was carbonized at 900°C. Platinum (Pt) nanoparticles were reduced by formic acid with catalyst supports. Compared to the untreated CNF/PANI composites, the carbonized composites were proven to be better supporting materials for the Pt nanocatalysts and showed superior performance as catalyst supports for methanol electrochemical oxidation. The current density of methanol oxidation on the catalyst with the core/shell nanostructured carbon materials is approximately seven times of that on the catalyst with CNF/PANI support. TEM tomography revealed that some Pt nanoparticles were embedded in the PANI shells of the CNF/PANI composites, which might decrease the electrocatalyst activity. TEM-energy dispersive spectroscopy mapping confirmed that the Pt nanoparticles in the inner tube of N-doped hollow CNFs could be accessed by the Nafion ionomer electrolyte, contributing to the catalytic oxidation of methanol. PMID:22385930

  8. A novel approach to arthritis treatment based on resveratrol and curcumin co-encapsulated in lipid-core nanocapsules: In vivo studies.

    PubMed

    Coradini, Karine; Friedrich, Rossana B; Fonseca, Francisco N; Vencato, Marina S; Andrade, Diego F; Oliveira, Cláudia M; Battistel, Ana Paula; Guterres, Silvia S; da Rocha, Maria Izabel U M; Pohlmann, Adriana R; Beck, Ruy C R

    2015-10-12

    Resveratrol and curcumin are two natural polyphenols extensively used due to their remarkable anti-inflammatory activity. The present work presents an inedited study of the in vivo antioedematogenic activity of these polyphenols co-encapsulated in lipid-core nanocapsules on Complete Freund's adjuvant (CFA)-induced arthritis in rats. Lipid-core nanocapsules were prepared by interfacial deposition of preformed polymer. Animals received a single subplantar injection of CFA in the right paw. Fourteen days after arthritis induction, they were treated with resveratrol, curcumin, or both in solution or loaded in lipid-core nanocapsules (1.75 mg/kg/twice daily, i.p.), for 8 days. At the doses used, the polyphenols in solution were not able to decrease paw oedema. However, nanoencapsulation improved the antioedematogenic activity of polyphenols at the same doses. In addition, the treatment with co-encapsulated polyphenols showed the most pronounced effects, where an inhibition of 37-55% was observed between day 16 and 22 after arthritis induction. This treatment minimized most of the histological changes observed, like fibrosis in synovial tissue, cartilage and bone loss. In addition, unlike conventionally arthritis treatment, resveratrol and curcumin co-encapsulated in lipid-core nanocapsules did not alter important hepatic biochemical markers (ALP, AST, and ALT). In conclusion, the strategy of co-encapsulating resveratrol and curcumin in lipid-core nanocapsules improves their efficacy as oedematogenic agents, with no evidence of hepatotoxic effects. This is a promising strategy for the development of new schemes for treatment of chronic inflammation diseases, like arthritis. PMID:26206297

  9. Dual-core antiresonant hollow core fibers.

    PubMed

    Liu, Xuesong; Fan, Zhongwei; Shi, Zhaohui; Ma, Yunfeng; Yu, Jin; Zhang, Jing

    2016-07-25

    In this work, dual-core antiresonant hollow core fibers (AR-HCFs) are numerically demonstrated, based on our knowledge, for the first time. Two fiber structures are proposed. One is a composite of two single-core nested nodeless AR-HCFs, exhibiting low confinement loss and a circular mode profile in each core. The other has a relatively simple structure, with a whole elliptical outer jacket, presenting a uniform and wide transmission band. The modal couplings of the dual-core AR-HCFs rely on a unique mechanism that transfers power through the air. The core separation and the gap between the two cores influence the modal coupling strength. With proper designs, both of the dual-core fibers can have low phase birefringence and short modal coupling lengths of several centimeters. PMID:27464191

  10. Summary final report: Contract between the Japan atomic power company and the U.S. Department of Energy Improvement of core safety - study on GEM (III)

    SciTech Connect

    Burke, T.M.; Lucoff, D.M.

    1997-03-18

    This report provides a summary of activities associated with the technical exchange between representatives of the Japan Atomic Power Company (JAPC) and the United States Department of Energy (DOE) regarding the development and testing of Gas Expansion Modules (GEM) at the Fast Flux Test Facility (FFTF). Issuance of this report completes the scope of work defined in the original contract between JAPC and DOE titled ''Study on Improvement of Core Safety - Study on GEM (III).'' Negotiations related to potential modification of the contract are in progress. Under the proposed contract modification, DOE would provide an additional report documenting FFTF pump start tests with GEMs and answer additional JAPC questions related to core safety with and without GEMs.

  11. Surface Carrier Dynamics on Semiconductor Studied with Femtosecond Core-Level Photoelectron Spectroscopy Using Extreme Ultraviolet High-Order Harmonic Source

    NASA Astrophysics Data System (ADS)

    Oguri, K.; Tsunoi, T.; Kato, K.; Nakano, H.; Nishikawa, T.; Gotoh, H.; Tateno, K.; Sogawa, T.

    2013-03-01

    We have used a femtosecond time-resolved core-level surface PES system based on the 92-eV harmonic source to study the surface carrier dynamics that induces the transient SPV on semiconductor surfaces. We clarified the temporal evolution of the transient SPV characterized by the time of the photo-generated carrier separation and recombination. This result demonstrates the potential of this technique for clarifying the initial stage of the surface carrier dynamics after photoexcitation.

  12. Ab-initio study of the physics and chemistry of metals in planetary core materials and nanomaterials at relevant thermodynamics conditions

    NASA Astrophysics Data System (ADS)

    Alnemrat, Sufian

    Material science investigates the relationship between the structure of materials at the atomic or molecular scales and their macroscopic properties. Ab-initio DFT, atomistic force-field, and molecular dynamic simulations have been used to investigate the electronic, optical, structural, magnetic properties of group II-VI semiconductor nanoparticles, metal organic frameworks, amide-water complexes, and planetary core materials at the atomic and/or molecular level. Structure, density of electronic states, magnetic dipole moments, and HOMO-LUMO gaps of surface-passivated ZnnSem, Cd nTem, CdTe-core/ZnTe-shell, and ZnSe-core/CdSe-shell nanocrystals are calculated using a first principles. The intrinsic magnetic dipole moments are found to be strongly size dependent. The detailed analysis of the dipole moment as a function of particle size shows the appearance of zincblende-wurtzite polymorphism in these nano-particles. Energy-efficient adsorption processes are considered promising alternatives to traditional separation techniques. Mg-MOF-74, a magnesium-based metal organic framework, has been used as an efficient adsorbent structure for several gas separation purposes. Adsorption equilibria and kinetics of ethane, ethylene, propane, and propylene on Mg-MOF-74 were determined at temperatures of 278, 298, and 318 K and pressures up to 100 kPa. A grand canonical Monte Carlo simulation was conducted to calculate the adsorption isotherms and to explore adsorption mechanisms. I found that propylene and propane have a stronger affinity to the Mg-MOF-74 adsorbent than ethane and ethylene because of their significant dipole moments. Ab-initio molecular dynamics simulations were carried out to study the role of equilibrium volume and magnetism in Fe and FeX alloys (X=Ni, O) and their stability at earth core conditions. This study provides new insights into the pressure dependence of magnetism by tracking the hybridization between crystal orbitals for pressures up to 600 GPa in

  13. Anisotropic charged core envelope star

    NASA Astrophysics Data System (ADS)

    Mafa Takisa, P.; Maharaj, S. D.

    2016-08-01

    We study a charged compact object with anisotropic pressures in a core envelope setting. The equation of state is quadratic in the core and linear in the envelope. There is smooth matching between the three regions: the core, envelope and the Reissner-Nordström exterior. We show that the presence of the electric field affects the masses, radii and compactification factors of stellar objects with values which are in agreement with previous studies. We investigate in particular the effect of electric field on the physical features of the pulsar PSR J1614-2230 in the core envelope model. The gravitational potentials and the matter variables are well behaved within the stellar object. We demonstrate that the radius of the core and the envelope can vary by changing the parameters in the speed of sound.

  14. Disequilibrium study of natural radionuclides of uranium and thorium series in cores and briny groundwaters from Palo Duro Basin, Texas

    SciTech Connect

    Laul, J.C.; Smith, M.R.

    1988-05-01

    The concentrations of natural radionuclides of the /sup 238/U and /232/Th series are reported in several cores and in ten deep and five shallow briny groundwaters from various formations in the Palo Duro Basin. The formations include Granite Wash, Pennsylvanian Granite Wash, Wolfcamp Carbonate, Pennsylvanian Carbonate, Seven River, Queen Grayburg, San Andres, Yates and Salado. The natural radionuclide data in cores suggest that the radionuclides have not migrated or been leached for at least a period of about 1 million years. Relative to the U and Th concentrations in cores, the brines are depleted by a factor of 10/sup 4/ to 10/sup 5/, indicating extremely low solubility of U and Th in brines. The natural radionuclide data in brines suggest that radium is not sorbed significantly and thus not retarded in nine deep brines. Radium is somewhat sorbed in one deep brine of Wolfcamp Carbonate and significantly sorbed in shallow brines. Relative to radium, the U, Th, Pb, Bi, and Po radionuclides are highly retarded by sorption. The retardation factors for /sup 228/Th range from 10/sup 2/ to 10/sup 3/, whereas those for /sup 230/Th and /sup 234/U range from 10/sup 3/ to 10/sup 5/, depending on the formation. The /sup 234/U//sup 238/U ratios in these brines are constant at about 1.5. The magnitude of the /sup 234/U//sup 230/Th ratio appears to reflect the degree of redox state of the aquifer's environment. The /sup 234/U//sup 230/Th ratio in nine deep brines is about unity, suggesting that U, like Th/sup +4/, is in the +4 state, which in turn suggests a reduced environment. 49 refs., 23 figs., 18 tabs.

  15. Microstructural studies of rocks from the 25 S oceanic core complex, along the Central Indian Ocean Ridge

    NASA Astrophysics Data System (ADS)

    Soda, Yusuke; Sawaguchi, Takashi; Enomoto, Tsubasa; Takagi, Hideo; Neo, Natsuki; Morishita, Tomoaki; Kumagai, Hidenori

    2010-05-01

    This study shows the microstructural development of rocks from the 25° S oceanic core complex (OCC) along the Central Indian Ocean Ridge, located near the Rodriguez Triple Junction. The samples described here are recovered by three submersible SHINKAI 6500 dives (Kumagai et al., 2008, Morishita et al., 2009). Characteristic foliated rocks with slickenline are recognized at a top surface of OCC, making up platy landform. Attitudes of those rocks are striking NE-SW and dipping to the NW and SE at moderate angle (20-30° ). Direction of lineation structures is perpendicular to the divergence ridge axis. We collect 55 samples during the three dives, and evaluate 10 samples as deformed rocks based on hand specimen scale structures on the shipboard. Deformed rocks distributed around the OCC surface consist of peridotite, gabbro, basalt, breccia and those altered rocks. Although almost olivine grains in peridotite are altered and replaced by talc, which forms anastmosing texture, olivine remnants show mylonitic texture characterized by undulose extinction and grain size reduction. Orthopyroxene grains are also elongated. Serpentine with platy shape makes up foliation, showing serpentinite mylonite texture. Olivine and serpentine are replaced by talc following mylonitization. Talc occurs as two different textures. One is static replacing primary minerals, and the other is syn-tectonic deformation textures such as foliated with shape preferred orientations, comprising talc schist. Gabbro also shows mylonitic structures featured by grain size reduction of plagioclase. Tremolite/actinolite is dominant facies in well foliated and altered gabbro in which has porphyroclasts of hornblende and plagioclase. Deformation of basalt is inhomogeneous and accompanying chloritization. Some part of basalt keeps plagioclase with basaltic textures, glassy texture and pseudomorph texture of them. Chlorite-rich basalt develops penetrative foliation and alters to chlorite schist. Breccia is

  16. Cross calibration between XRF and ICP-MS for high spatial resolution analysis of ombrotrophic peat cores for palaeoclimatic studies.

    PubMed

    Poto, Luisa; Gabrieli, Jacopo; Crowhurst, Simon; Agostinelli, Claudio; Spolaor, Andrea; Cairns, Warren R L; Cozzi, Giulio; Barbante, Carlo

    2015-01-01

    Ombrotrophic peatlands are remarkable repositories of high-quality climatic signals because their only source of nutrients is precipitation. Although several analytical techniques are available for analysing inorganic components in peat samples, they generally provide only low-resolution data sets. Here we present a new analytical approach for producing high-resolution data on main and trace elements from ombrotrophic peat cores. Analyses were carried out on a 7-m-long peat core collected from Danta di Cadore, North-Eastern Italy (46° 34' 16″ N, 12° 29' 58″ E). Ca, Ti, Cr, Fe, Cu, Zn, Ga, Sr, Y, Cd, Ba and Pb were detected at a resolution of 2.5 mm with a non-destructive X-ray fluorescence core scanner (XRF-CS). Calibration and quantification of the XRF-CS intensities was obtained using collision reaction cell inductively coupled plasma quadruple mass spectrometry (CRC-ICP-QMS). CRC-ICP-QMS measurements were carried out on discrete samples at a resolution of 1 cm, after dissolution of 150-mg aliquots with 9 ml HNO3 and 1 ml HF at 220 °C in a microwave system. We compare qualitative XRF-CS and quantitative CRC-ICP-MS data and, however the several sources of variability of the data, develop a robust statistical approach to determine the R (2) and the coefficient of a simple regression model together with confidence intervals. Perfect positive correlations were estimated for Cd, Cr, Pb, Sr, Ti and Zn; high positive correlations for Ba (0.8954), Y (0.7378), Fe (0.7349) and Cu (0.7028); while moderate positive correlations for Ga (0.5951) and Ca (0.5435). With our results, we demonstrate that XRF scanning techniques can be used, together with other well-established geochemical techniques (such as ICP-MS), to produce high-resolution (up to 2.5 mm) quantitative data from ombrotrophic peat bog cores. PMID:25404165

  17. Lunar Polar Coring Lander

    NASA Technical Reports Server (NTRS)

    Angell, David; Bealmear, David; Benarroche, Patrice; Henry, Alan; Hudson, Raymond; Rivellini, Tommaso; Tolmachoff, Alex

    1990-01-01

    Plans to build a lunar base are presently being studied with a number of considerations. One of the most important considerations is qualifying the presence of water on the Moon. The existence of water on the Moon implies that future lunar settlements may be able to use this resource to produce things such as drinking water and rocket fuel. Due to the very high cost of transporting these materials to the Moon, in situ production could save billions of dollars in operating costs of the lunar base. Scientists have suggested that the polar regions of the Moon may contain some amounts of water ice in the regolith. Six possible mission scenarios are suggested which would allow lunar polar soil samples to be collected for analysis. The options presented are: remote sensing satellite, two unmanned robotic lunar coring missions (one is a sample return and one is a data return only), two combined manned and robotic polar coring missions, and one fully manned core retrieval mission. One of the combined manned and robotic missions has been singled out for detailed analysis. This mission proposes sending at least three unmanned robotic landers to the lunar pole to take core samples as deep as 15 meters. Upon successful completion of the coring operations, a manned mission would be sent to retrieve the samples and perform extensive experiments of the polar region. Man's first step in returning to the Moon is recommended to investigate the issue of lunar polar water. The potential benefits of lunar water more than warrant sending either astronauts, robots or both to the Moon before any permanent facility is constructed.

  18. Magnetic field assisted self-assembly of ferrite-ferroelectric core-shell nanofibers and studies on magneto-electric interactions

    SciTech Connect

    Sreenivasulu, G.; Zhang, Ru; Sharma, K.; Janes, C.; Mukundan, A.; Srinivasan, G.; Popov, Maksym

    2014-02-03

    Core-shell nanofibers of nickel ferrite and lead zirconate titanate have been synthesized by electrospinning, assembled into superstructure in uniform or non-uniform magnetic fields, and have been characterized in terms of ferroic order parameters and strain mediated magneto-electric (ME) coupling. The core-shell structure was confirmed by electron microscopy and scanning probe microscopy. Studies on magnetic field induced polarization P in assembled samples showed a decrease or increase in P, depending on the nature of fibers and strengthening of ME coupling with change in remnant-P as high as 32%. Strong ME interactions were evident from H-induced variation in permittivity at 20–22 GHz.

  19. Study of optical nonlinearity of CdSe and CdSe@ZnO core-shell quantum dots in nanosecond regime

    NASA Astrophysics Data System (ADS)

    Deepika; Dhar, Rakesh; Mohan, Devendra

    2015-12-01

    Thioglycolic acid capped cadmium selenide (CdSe) and CdSe@ZnO core-shell quantum dots have been synthesized in aqueous phase. The sample was characterized by UV-vis spectrophotometer, TEM and Z-scan technique. The nonlinear optical parameters viz. nonlinear absorption coefficient (β), nonlinear refractive index (n2) and third-order nonlinear susceptibilities (χ3) of quantum dots have been estimated using second harmonic of Nd:YAG laser. The study predicts that CdSe@ZnO quantum dots exhibits strong nonlinearity as compared to core CdSe quantum dots. The nonlinearity in quantum dots is attributed to the presence of resonant excitation and free optical processes. The presence of RSA in these nanoparticles makes them a potential material for the development of optical limiter.

  20. Study of the rhizobacterium Azospirillum brasilense Sp245 using Mössbauer spectroscopy with a high velocity resolution: Implication for the analysis of ferritin-like iron cores

    NASA Astrophysics Data System (ADS)

    Alenkina, I. V.; Oshtrakh, M. I.; Tugarova, A. V.; Biró, B.; Semionkin, V. A.; Kamnev, A. A.

    2014-09-01

    The results of a comparative study of two samples of the rhizobacterium Azospirillum brasilense (strain Sp245) prepared in different conditions and of human liver ferritin using Mössbauer spectroscopy with a high velocity resolution demonstrated the presence of ferritin-like iron (i.e. iron similar to that found in ferritin-like proteins) in the bacterium. Mössbauer spectra of these samples were fitted in two ways: as a rough approximation using a one quadrupole doublet fit (the homogeneous iron core model) and using a superposition of quadrupole doublets (the heterogeneous iron core model). Both results demonstrated differences in the Mössbauer parameters for mammalian ferritin and for bacterial ferritin-like iron. Moreover, some differences in the Mössbauer parameters were observed between the two samples of A. brasilense Sp245 related to the differences in their preparation conditions.

  1. Electronic Charges and Electric Potential at LaAlO3/SrTiO3 Interfaces Studied by Core-Level Photoemission Spectroscopy

    SciTech Connect

    Hwang, Harold

    2011-08-19

    We studied LaAlO{sub 3}/SrTiO{sub 3} interfaces for varying LaAlO{sub 3} thickness by core-level photoemission spectroscopy. In Ti 2p spectra for conducting 'n-type' interfaces, Ti{sup 3+} signals appeared, which were absent for insulating 'p-type' interfaces. The Ti{sup 3+} signals increased with LaAlO{sub 3} thickness, but started well below the critical thickness of 4 unit cells for metallic transport. Core-level shifts with LaAlO{sub 3} thickness were much smaller than predicted by the polar catastrophe model. We attribute these observations to surface defects/adsorbates providing charges to the interface even below the critical thickness.

  2. DFT study of Fe-Ni core-shell nanoparticles: Stability, catalytic activity, and interaction with carbon atom for single-walled carbon nanotube growth

    NASA Astrophysics Data System (ADS)

    Yang, Zhimin; Wang, Qiang; Shan, Xiaoye; Li, Wei-qi; Chen, Guang-hui; Zhu, Hongjun

    2015-02-01

    Metal catalysts play an important role in the nucleation and growth of single-walled carbon nanotubes (SWCNTs). It is essential for probing the nucleation and growth mechanism of SWCNTs to fundamentally understand the properties of the metal catalysts and their interaction with carbon species. In this study, we systematically studied the stability of 13- and 55-atom Fe and Fe-Ni core-shell particles as well as these particles interaction with the carbon atoms using the density functional theory calculations. Icosahedral 13- and 55-atom Fe-Ni core-shell bimetallic particles have higher stability than the corresponding monometallic Fe and Ni particles. Opposite charge transfer (or distribution) in these particles leads to the Fe surface-shell displays a positive charge, while the Ni surface-shell exhibits a negative charge. The opposite charge transfer would induce different chemical activities. Compared with the monometallic Fe and Ni particles, the core-shell bimetallic particles have weaker interaction with C atoms. More importantly, C atoms only prefer staying on the surface of the bimetallic particles. In contrast, C atoms prefer locating into the subsurface of the monometallic particles, which is more likely to form stable metal carbides. The difference of the mono- and bimetallic particles on this issue may result in different nucleation and growth mechanism of SWCNTs. Our findings provide useful insights for the design of bimetallic catalysts and a better understanding nucleation and growth mechanism of SWCNTs.

  3. DFT study of Fe-Ni core-shell nanoparticles: Stability, catalytic activity, and interaction with carbon atom for single-walled carbon nanotube growth

    SciTech Connect

    Yang, Zhimin; Wang, Qiang Shan, Xiaoye; Zhu, Hongjun; Li, Wei-qi; Chen, Guang-hui

    2015-02-21

    Metal catalysts play an important role in the nucleation and growth of single-walled carbon nanotubes (SWCNTs). It is essential for probing the nucleation and growth mechanism of SWCNTs to fundamentally understand the properties of the metal catalysts and their interaction with carbon species. In this study, we systematically studied the stability of 13- and 55-atom Fe and Fe-Ni core-shell particles as well as these particles interaction with the carbon atoms using the density functional theory calculations. Icosahedral 13- and 55-atom Fe-Ni core-shell bimetallic particles have higher stability than the corresponding monometallic Fe and Ni particles. Opposite charge transfer (or distribution) in these particles leads to the Fe surface-shell displays a positive charge, while the Ni surface-shell exhibits a negative charge. The opposite charge transfer would induce different chemical activities. Compared with the monometallic Fe and Ni particles, the core-shell bimetallic particles have weaker interaction with C atoms. More importantly, C atoms only prefer staying on the surface of the bimetallic particles. In contrast, C atoms prefer locating into the subsurface of the monometallic particles, which is more likely to form stable metal carbides. The difference of the mono- and bimetallic particles on this issue may result in different nucleation and growth mechanism of SWCNTs. Our findings provide useful insights for the design of bimetallic catalysts and a better understanding nucleation and growth mechanism of SWCNTs.

  4. Core-shell Rh-Pt nanocubes: A model for studying compressive strain effects in bimetallic nanocatalysts

    NASA Astrophysics Data System (ADS)

    Harak, Ethan William

    Shape-controlled bimetallic nanocatalysts often have increased activities and stabilities over their monometallic counterparts due to surface strain effects and electron transfer between the two metals. Here, we demonstrate that the degree of surface strain can be manipulated in shape-controlled nanocrystals through a bimetallic core shell architecture. This ability is achieved in a model core shell Rh Pt nanocube system through control of shell thickness. An increase in the Pt shell thickness leads to more compressive strain, which can increase the Pt 4f7/2 binding energy by as much as 0.13 eV. This change in electronic structure is correlated with a weakening of surface-adsorbate interactions, which we exploit to reduce catalyst poisoning by CO during formic acid electrooxidation. In fact, by precisely controlling the Pt shell thickness, the maximum current density achieved with Rh Pt nanocubes was 3.5 times greater than that achieved with similarly sized Pt nanocubes, with decreased CO generation as well. This system serves as a model for how bimetallic architectures can be used to manipulate the electronic structure of nanoparticle surfaces for efficient catalysis. The strategy employed here should enable the performance of bimetallic nanomaterials comprised of more cost-effective metals to be enhanced as well.

  5. Studies of Electron Temperature Fluctuations in the Core of Alcator C-Mod Plasmas via Correlation ECE

    NASA Astrophysics Data System (ADS)

    Oi, C.; Sung, C.; Howard, N.; White, A. E.; Irby, J.; Leccacorvi, R.; Vieira, R.; Rice, J.; Gao, C.

    2012-10-01

    A correlation electron cyclotron emission (CECE) diagnostic has been designed and installed at the Alcator C-Mod tokamak to measure long wavelength fluctuations in electron temperature [C. Sung, this conference, C-Mod oral session]. It is important to characterize turbulent fluctuations in the plasma in order to better understand and predict transport, since the cross-magnetic field transport of particles and energy in fusion plasmas exceeds the values predicted by neoclassical theory. The first electron temperature fluctuation data collected from Alcator C-Mod ohmic plasmas has shown that as the ohmic confinement regime transitions from Linear Ohmic Confinement (LOC) to Saturated Ohmic Confinement (SOC) there is a decrease in the core electron temperature fluctuation level. The edge electron temperature fluctuations are similar between the two modes, suggesting that mainly the core turbulence characteristics change when there is a shift between LOC and SOC regimes. In both ohmic and ICRH plasmas, the measured spectrum is seen to broaden in response to increases in plasma rotation; and fluctuation level increases with radius. A description of the C-Mod CECE diagnostic will be presented, along with the initial measurements of turbulent electron temperature fluctuations.

  6. Study on preparation and microwave absorption property of the core-nanoshell composite materials doped with La.

    PubMed

    Wei, Liqiu; Che, Ruxin; Jiang, Yijun; Yu, Bing

    2013-12-01

    Microwave absorbing material plays a great role in electromagnetic pollution controlling, electromagnetic interference shielding and stealth technology, etc. The core-nanoshell composite materials doped with La were prepared by a solid-state reaction method, which is applied to the electromagnetic wave absorption. The core is magnetic fly-ash hollow cenosphere, and the shell is the nanosized ferrite doped with La. The thermal decomposition process of the sample was investigated by thermogravimetry and differential thermal analysis. The morphology and components of the composite materials were investigated by the X-ray diffraction analysis, the microstructure was observed by scanning electron microscope and transmission electron microscope. The results of vibrating sample magnetometer analysis indicated that the exchange-coupling interaction happens between ferrite of magnetic fly-ash hollow cenosphere and nanosized ferrite coating, which caused outstanding magnetic properties. The microwave absorbing property of the sample was measured by reflectivity far field radar cross section of radar microwave absorbing material with vector network analyzer. The results indicated that the exchange-coupling interaction enhanced magnetic loss of composite materials. Therefore, in the frequency of 5 GHz, the reflection coefficient can achieve -24 dB. It is better than single material and is consistent with requirements of the microwave absorbing material at the low-frequency absorption. PMID:25078834

  7. Study of Iron Dimers Reveals Angular Dependence of Valence-to-Core X-ray Emission Spectra

    PubMed Central

    2015-01-01

    Transition-metal Kβ X-ray emission spectroscopy (XES) is a developing technique that probes the occupied molecular orbitals of a metal complex. As an element-specific probe of metal centers, Kβ XES is finding increasing applications in catalytic and, in particular, bioinorganic systems. For the continued development of XES as a probe of these complex systems, however, the full range of factors which contribute to XES spectral modulations must be explored. In this report, an investigation of a series of oxo-bridged iron dimers reveals that the intensity of valence-to-core features is sensitive to the Fe–O–Fe bond angle. The intensity of these features has a well-known dependence on metal–ligand bond distance, but a dependence upon bond angle has not previously been documented. Herein, we explore the angular dependence of valence-to-core XES features both experimentally and computationally. Taken together, these results show that, as the Fe–O–Fe angle decreases, the intensity of the Kβ″ feature increases and that this effect is modulated by increasing amounts of Fe np mixing into the O 2s orbital at smaller bond angles. The relevance of these findings to the identification of oxygenated intermediates in bioinorganic systems is highlighted, with special emphasis given to the case of soluble methane monooxygenase. PMID:25211540

  8. Optical phonon modes of III-V nanoparticles and indium phosphide/II-VI core-shell nanoparticles: A Raman and infrared study

    NASA Astrophysics Data System (ADS)

    Manciu, Felicia Speranta

    The prospects for realizing efficient nanoparticle light emitters in the visible/near IR for communications and bio-medical applications have benefited from progress in chemical fabrication of nanoparticles. III-V semiconductor nanopaticles such as GaP and InP are promising materials for the development of "blue" and "green" emitters, respectively, due to their large effective bandgaps. Enhanced emission efficiency has been achieved for core-shell nanoparticles, since inorganic shell materials increase electronic tunability and may decrease surface defects that often occur for nanoparticles capped with organic molecules. Also, the emission wavelength of InP nanoparticle cores can be tuned from green to red by changing the shell material in InP/II-VI core-shell nanoparticles. Investigations of phonon modes in nanocrystals are of both fundamental and applied interest. In the former case the optical phonon modes, such as surface/interface modes, are dependent on the nanoparticle dimensions, and also can provide information about dynamical properties of the nanoparticles and test the validity of various theoretical approaches. In the latter case the vibronic properties of nanoparticle emitters are controlled by confined phonons and modifications of the electron-phonon interaction by the confinement. Thus, the objective of the present thesis is the detailed study of the phonon modes of III-V nanoparticles (GaP and InP) and InP/II-VI core-shell nanoparticles by IR absorption and Raman scattering spectroscopies, and an elucidation of their complex vibrational properties. With the exception of three samples (two GaP and one InP), all samples were synthesized by a novel colloidal chemistry method, which does not requires added surfactant, but rather treatment of the corresponding precursors in octadecene noncoordinative solvent. Sample quality was characterized by ED, TEM and X-ray diffraction. Based on a comparison with a dielectric continuum model, the observed features

  9. DFT study of structure, IR and Raman spectra of the first generation dendron built from cyclotriphosphazene core with terminal carbamate and ester groups

    NASA Astrophysics Data System (ADS)

    Furer, V. L.; Vandyukov, A. E.; Fuchs, S.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

    2012-06-01

    The FTIR and FT-Raman spectra of the first generation dendron built from the cyclotriphosphazene core, five arms sbnd Osbnd C6H4sbnd CHdbnd Nsbnd N(CH3)sbnd P(S)rbond2 with ten carbamate terminal groups and one ester function Gv1 have been recorded. The IR and Raman spectra of the zero generation dendron Gv0 and first generation dendrimer G1 with the same core and terminal groups were also examined. The structural optimization and normal mode analysis were performed for dendron Gv1 on the basis of the density functional theory (DFT). The calculated geometrical parameters and harmonic vibrational frequencies are predicted in a good agreement with the experimental data. It was found that Gv1 has a concave lens structure with planar sbnd Osbnd C6H4sbnd CHdbnd Nsbnd N(CH3)sbnd P(S)rbond2 fragments and slightly non-planar cyclotriphosphazene core. The carbamate groups attached to different arms show significant deviations from a symmetrical arrangement relative to the local planes of repeating units. The experimental IR spectrum of Gv1 dendron was interpreted by means of potential energy distributions. The strong band 1604 cm-1 shows marked changes of the optical density in dependence of the carbamate, ester or azomethyne substituents in the aromatic ring. The frequencies of ν(Nsbnd H) and ν(Cdbnd O) bands in the IR spectra reveal the presence of the different types of H-bonds in the studied dendrimers.

  10. Resonant Auger spectroscopy study of charge transfer phenomena in N 1s core-excited acetonitrile adsorbates on Si(0 0 1)-2 × 1

    NASA Astrophysics Data System (ADS)

    Gallet, J.-J.; Bournel, F.; Carniato, S.; Dufour, G.; Rochet, F.; Rangan, S.; Sirotti, F.

    2007-01-01

    Acetonitrile (CH 3CN) adsorbs on Si(0 0 1)-2 × 1 at room temperature under two forms, a cycloaddition-like adduct (Si-C dbnd N-Si) and a pendent cyano (Si-CH 2-C tbnd N) resulting from the decomposition of the molecule. Resonant Auger spectroscopy has been used to study the excited-state-dependent electron transfer from the N 1s core-excited molecular adsorbate to the silicon substrate, using the core-hole lifetime (˜6 fs) as an internal clock. It is shown that the π C dbnd N ∗ NEXAFS state lies within the silicon bandgap because of a core-excitonic effect. Therefore no charge transfer of the excited electron to the substrate is observed. On the other hand the π C tbnd N ∗ NEXAFS state is placed within the silicon conduction band. Excitation to this orbital leads to valence/Auger spectra in which both resonant and normal Auger contributions are observed. Therefore there is evidence for a charge transfer from the pendent C tbnd N to the silicon surface, on a timescale estimated to tens of femtoseconds.

  11. Using core sets of the international classification of functioning, disability and health (ICF) to measure disability in vestibular disorders: study protocol.

    PubMed

    Grill, Eva; Furman, Joseph M; Alghwiri, Alia A; Müller, Martin; Whitney, Susan L

    2013-01-01

    Symptom frequency and severity in vestibular disorders often do not correlate well with patients' restrictions of activities of daily living and limitations of participation. Due to the lack of appropriate patient reported outcome measures (PRO), the extent of limitations and restrictions is mostly unknown. The International Classification of Functioning, Disability and Health (ICF) is a conceptual framework and classification to evaluate all aspects of health and disability. An ICF-based measure, the Vestibular and Participation Measure (VAP), was recently proposed. Also, an ICF Core Set for vertigo, dizziness and balance disorders was developed to describe what aspects of functioning should be measured. This study protocol describes the development and cross-cultural validation of a new measure, the VAP-extended (VAP-e), based on VAP and ICF Core Set on three continents. To determine objectivity and cross-cultural validity of the VAP and to find potentially redundant items, Rasch models will be used. The VAP-e will be created by modifying or adding items from the Activities and Participation and Environmental Factors component of the ICF Core Set. Reliability, objectivity and responsiveness of the VAP-e will be tested. PMID:24447970

  12. Site- and geometry-specific CH...O interaction in small acetaldehyde clusters studied with core-electron excitation spectroscopy in the carbon K-edge region

    NASA Astrophysics Data System (ADS)

    Tabayashi, K.; Tsutsumi, Y.; Chohda, M.; Takahashi, O.; Tamenori, Y.; Higuchi, I.; Suzuki, I. H.; Nagaoka, S.; Gejo, T.; Honma, K.

    2011-04-01

    Site-dependent C1s-core excitation spectra of small acetaldehyde (AAL) clusters have been studied under the cluster regime of beam conditions. The excitation spectra of the clusters were generated by monitoring the partial-ion-yields of cluster-origin fragments. Comparison of the cluster bands with the monomer bands revealed that the band intensities of C1s core-to-Rydberg transitions come to be strongly excitation-site dependent upon cluster formation showing significant reduction of C1sHCO→Ryd bands relative to the monomer bands. Computer modeling of X-ray absorption spectra using a density functional theory calculation demonstrated that the intensity reduction is the outcome of the site- and geometry-specific CH...O interaction where hydrogen-bonding association between the aldehyde (HCO) sites of different AAL molecules takes place exclusively within the clusters. As the representatives of small AAL clusters (n>=3), two types of molecular complexes (a planar cyclic trimer and a tetramer with a stack of two dimers) were derived to rationalize the site-dependence of the experimental C1s excitation spectra. Spectral simulation of the above complexes could reproduce the experimental site-dependence of the core-to-Rydberg band-features upon clusterization, indicative of significant contribution of these clusters under the present beam-stagnation condition.

  13. Comparison of fused-core and conventional particle size columns by LC-MS/MS and UV: application to pharmacokinetic study.

    PubMed

    Song, Wei; Pabbisetty, Deepthi; Groeber, Elizabeth A; Steenwyk, Rick C; Fast, Douglas M

    2009-10-15

    The chromatographic performance of fused-core (superficially porous) HPLC packing materials was compared with conventional fully porous particle materials for LC-MS/MS analysis of two pharmaceuticals in rat plasma. Two commercially available antidepressants, imipramine and desipramine, were assayed using a conventional analytical C(18) column (5 microm, 2.0 mm x 30 mm) and a fused-core C(18) column (2.7 microm, 2.1 mm x 30 mm). Retention time, column efficiency, pressure drop, resolution, and loading capacity were compared under the same operating conditions. The fused-core column demonstrated reduced assay time by 34% and 2-3-fold increased efficiency (N). Loading capacity up to 25 microl of extract injected on column showed no peak distortion. The registered back-pressure from a flow rate of 1.0 ml/min did not exceed 3400 psi making it compatible with standard HPLC equipment (typically rated to 6000 psi). Two mobile phases were examined, and morpholine as an organic base modifier yielded a 2-5-fold increase in S/N near the limit of detection over triethylamine. The 2.7 microm fused-core column was applied to the analysis of imipramine and desipramine in extracted, protein precipitated rat plasma by LC-MS/MS. The calibration curves were linear in the concentration range of 0.5-1000 ng/ml for both imipramine and desipramine. Intra-run precisions (%CV) and accuracies (%bias) were within +/-7.8% and +/-7.3% at three QC levels and within 14.7% and 14.4% at the LOQ level for both analytes. Following a single method qualification run, the method was applied to the quantitation of pharmacokinetic study samples after oral administration of imipramine to male rats. PMID:19540084

  14. Fabrication and spectroscopic studies of folic acid-conjugated Fe3O4@Au core-shell for targeted drug delivery application

    NASA Astrophysics Data System (ADS)

    Karamipour, Sh.; Sadjadi, M. S.; Farhadyar, N.

    2015-09-01

    Gold coated magnetite core shell is a kind of nanoparticle that include magnetic iron oxide core with a thin layer nanogold. Fe3O4-gold core-shell nanostructure can be used in biomedical applications such as magnetic bioseparation, bioimaging, targeting drug delivery and cancer treatment. In this study, the synthesis and characterization of gold coated magnetite nanoparticles were discussed. Magnetite nanoparticles with an average size of 6 nm in diameter were synthesized by the chemical co-precipitation method and gold-coated Fe3O4 core-shell nanostructures were produced with an average size of 11.5 nm in diameter by reduction of Au3+ with citrate ion in the presence of Fe3O4. Folate-conjugated gold coated magnetite nanoparticles were synthesized to targeting folate receptor that is overexpressed on the surface of cancerous cells. For this purpose, we used L-cysteine, as a bi-functional linker for attachment to gold surface and it was linked to the gold nanoparticles surface through its thiol group. Then, we conjugated amino-terminated nanoparticles to folic acid with an amide-linkage formation. These gold magnetic nanoparticles were characterized by various techniques such as X-ray powder diffraction (XRD) analysis, Fourier transform infrared spectrometer (FT-IR), UV-visible spectroscopy, transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), dispersive analysis of X-ray (EDAX) and vibrating sample magnetometer (VSM) analysis. The magnetic and optical properties of Fe3O4 nanostructure were changed by gold coating and attachment of L-cysteine and folic acid to Fe3O4@Au nanoparticles.

  15. Properties of a soft-core model of methanol: An integral equation theory and computer simulation study

    SciTech Connect

    Huš, Matej; Urbic, Tomaz; Munaò, Gianmarco

    2014-10-28

    Thermodynamic and structural properties of a coarse-grained model of methanol are examined by Monte Carlo simulations and reference interaction site model (RISM) integral equation theory. Methanol particles are described as dimers formed from an apolar Lennard-Jones sphere, mimicking the methyl group, and a sphere with a core-softened potential as the hydroxyl group. Different closure approximations of the RISM theory are compared and discussed. The liquid structure of methanol is investigated by calculating site-site radial distribution functions and static structure factors for a wide range of temperatures and densities. Results obtained show a good agreement between RISM and Monte Carlo simulations. The phase behavior of methanol is investigated by employing different thermodynamic routes for the calculation of the RISM free energy, drawing gas-liquid coexistence curves that match the simulation data. Preliminary indications for a putative second critical point between two different liquid phases of methanol are also discussed.

  16. Drill core LB-08A, Bosumtwi impact structure, Ghana: Petrographic and shock metamorphic studies of material from the central uplift

    NASA Astrophysics Data System (ADS)

    Ferrière, Ludovic; Koeberl, Christian; Reimold, Wolf Uwe

    During a recent drilling project sponsored by the International Continental Scientific Drilling Progam (ICDP), two boreholes (LB-07A and LB-08A) were drilled into the crater fill of the Bosumtwi impact structure and the underlying basement, into the deep crater moat and the outer flank of the central uplift, respectively. The Bosumtwi impact structure in Ghana (West Africa), which is 10.5 km in diameter and 1.07 Myr old, is largely filled by Lake Bosumtwi. Here we present the lithostratigraphy of drill core LB-08A (recovered between 235.6 and 451.33 m depth below lake level) as well as the first mineralogical and petrographic observations of samples from this core. This drill core consists of approximately 25 m of polymict, clast-supported lithic breccia intercalated with suevite, which overlies fractured/brecciated metasediment that displays a large variation in lithology and grain size. The lithologies present in the central uplift are metasediments composed dominantly of fine-grained to gritty meta-graywacke, phyllite, and slate, as well as suevite and polymict lithic impact breccia. The suevites, principally present between 235.6 and 240.5 m and between 257.6 and 262.2 m, display a fine-grained fragmental matrix (about 39 to 45 vol%) and a variety of lithic and mineral clasts that include meta-graywacke, phyllite, slate, quartzite, carbon-rich organic shale, and calcite, as well as melt particles, fractured quartz, unshocked quartz, unshocked feldspar, quartz with planar deformation features (PDFs), diaplectic quartz glass, mica, epidote, sphene, and opaque minerals). The crater-fill suevite contains calcite clasts but no granite clasts, in contrast to suevite from outside the northern crater rim. The presence of melt particles in suevite samples from the uppermost 25 meters of the core and in suevite dikelets in the basement is an indicator of shock pressures exceeding 45 GPa. Quartz grains present in suevite and polymict lithic impact breccia abundantly

  17. Multiband observations of Cygnus A: A study of pressure balance in the core of a powerful radio galaxy

    NASA Technical Reports Server (NTRS)

    Carilli, Chris; Conner, Sam; Dreher, John; Perley, Rick

    1990-01-01

    Cygnus A is a powerful double radio source associated with a giant elliptical galaxy at the center of a poor cluster of galaxies. The radio source also sits within the core radius of a dense, cooling flow, x ray emitting cluster gas. Optical spectroscopy and narrow band imaging have revealed copious amounts of narrow line emission from the inner 20 kpc of the associated galaxy. Researchers assume H sub o = 75 km sec (-1) Mpc(-1). Discussed here are the pressures in the three components of the Interstellar Medium (ISM) (i.e., the radio, x ray, and line emitting fluids) within a radius of about 15 kpc of the active nucleus of the Cygnus A galaxy.

  18. Fluid inclusions and preliminary studies of hydrothermal alteration in core hole PLTG-1, Platanares geothermal area, Honduras

    USGS Publications Warehouse

    Bargar, K.E.

    1991-01-01

    The Platanares geothermal area in western Honduras consists of more than 100 hot springs that issue from numerous hot-spring groups along the banks or within the streambed of the Quebrada de Agua Caliente (brook of hot water). Evaluation of this geothermal area included drilling a 650-m deep PLTG-1 drill hole which penetrated a surface mantling of stream terrace deposits, about 550 m of Tertiary andesitic lava flows, and Cretaceous to lower Tertiary sedimentary rocks in the lower 90 m of the drill core. Fractures and cavities in the drill core are partly to completely filled by hydrothermal minerals that include quartz, kaolinite, mixed-layer illite-smectite, barite, fluorite, chlorite, calcite, laumontite, biotite, hematite, marcasite, pyrite, arsenopyrite, stibnite, and sphalerite; the most common open-space fillings are calcite and quartz. Biotite from 138.9-m depth, dated at 37.41 Ma by replicate 40Ar/39 Ar analyses using a continuous laser system, is the earliest hydrothermal mineral deposited in the PLTG-1 drill core. This mid-Tertiary age indicates that at least some of the hydrothermal alteration encountered in the PLTG-1 drill core occured in the distant past and is unrelated to the present geothermal system. Furthermore, homogenization temperatures (Th) and melting-point temperatures (Tm) for fluid inclusions in two of the later-formed hydrothermal minerals, calcite and barite, suggest that the temperatures and concentration of dissolved solids of the fluids present at the time these fluid inclusions formed were very different from the present temperatures and fluid chemistry measured in the drill hole. Liquid-rich secondary fluid inclusions in barite and caicite from drill hole PLTG-1 have Th values that range from about 20??C less than the present measured temperature curve at 590.1-m depth to as much as 90??C higher than the temperature curve at 46.75-m depth. Many of the barite Th measurements (ranging between 114?? and 265??C) plot above the

  19. Properties of a soft-core model of methanol: An integral equation theory and computer simulation study

    PubMed Central

    Huš, Matej; Munaò, Gianmarco; Urbic, Tomaz

    2014-01-01

    Thermodynamic and structural properties of a coarse-grained model of methanol are examined by Monte Carlo simulations and reference interaction site model (RISM) integral equation theory. Methanol particles are described as dimers formed from an apolar Lennard-Jones sphere, mimicking the methyl group, and a sphere with a core-softened potential as the hydroxyl group. Different closure approximations of the RISM theory are compared and discussed. The liquid structure of methanol is investigated by calculating site-site radial distribution functions and static structure factors for a wide range of temperatures and densities. Results obtained show a good agreement between RISM and Monte Carlo simulations. The phase behavior of methanol is investigated by employing different thermodynamic routes for the calculation of the RISM free energy, drawing gas-liquid coexistence curves that match the simulation data. Preliminary indications for a putative second critical point between two different liquid phases of methanol are also discussed. PMID:25362323

  20. On sulfur core level binding energies in thiol self-assembly and alternative adsorption sites: An experimental and theoretical study.

    PubMed

    Jia, Juanjuan; Kara, Abdelkader; Pasquali, Luca; Bendounan, Azzedine; Sirotti, Fausto; Esaulov, Vladimir A

    2015-09-14

    Characteristic core level binding energies (CLBEs) are regularly used to infer the modes of molecular adsorption: orientation, organization, and dissociation processes. Here, we focus on a largely debated situation regarding CLBEs in the case of chalcogen atom bearing molecules. For a thiol, this concerns the case when the CLBE of a thiolate sulfur at an adsorption site can be interpreted alternatively as due to atomic adsorption of a S atom, resulting from dissociation. Results of an investigation of the characteristics of thiol self-assembled monolayers (SAMs) obtained by vacuum evaporative adsorption are presented along with core level binding energy calculations. Thiol ended SAMs of 1,4-benzenedimethanethiol (BDMT) obtained by evaporation on Au display an unconventional CLBE structure at about 161.25 eV, which is close to a known CLBE of a S atom on Au. Adsorption and CLBE calculations for sulfur atoms and BDMT molecules are reported and allow delineating trends as a function of chemisorption on hollow, bridge, and atop sites and including the presence of adatoms. These calculations suggest that the 161.25 eV peak is due to an alternative adsorption site, which could be associated to an atop configuration. Therefore, this may be an alternative interpretation, different from the one involving the adsorption of atomic sulfur resulting from the dissociation process of the S-C bond. Calculated differences in S(2p) CLBEs for free BDMT molecules, SH group sulfur on top of the SAM, and disulfide are also reported to clarify possible errors in assignments. PMID:26374051