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Sample records for high-resolution transient recorder

  1. Development and Performance Verification of the GANDALF High-Resolution Transient Recorder System

    CERN Document Server

    Bartknecht, Stefan; Herrmann, Florian; Königsmann, Kay; Lauser, Louis; Schill, Christian; Schopferer, Sebastian; Wollny, Heiner

    2011-01-01

    With present-day detectors in high energy physics one often faces fast analog pulses of a few nanoseconds length which cover large dynamic ranges. In many experiments both amplitude and timing information have to be measured with high accuracy. Additionally, the data rate per readout channel can reach several MHz, which leads to high demands on the separation of pile-up pulses. For an upgrade of the COMPASS experiment at CERN we have designed the GANDALF transient recorder with a resolution of 12bit@1GS/s and an analog bandwidth of 500\\:MHz. Signals are digitized with high precision and processed by fast algorithms to extract pulse arrival times and amplitudes in real-time and to generate trigger signals for the experiment. With up to 16 analog channels, deep memories and a high data rate interface, this 6U-VME64x/VXS module is not only a dead-time free digitization unit but also has huge numerical capabilities provided by the implementation of a Virtex5-SXT FPGA. Fast algorithms implemented in the FPGA may b...

  2. Development of a 1 GS/s high-resolution transient recorder

    CERN Document Server

    Bartknecht, S; Herrmann, F; Königsmann, K; Lauser, L; Schill, C; Schopferer, S; Wollny, H

    2009-01-01

    With present-day detectors in high energy physics one is often faced with short analog pulses of a few nanoseconds length which may cover large dynamic ranges. In many experiments both amplitude and timing information have to be measured with high accuracy. Additionally, the data rate per readout channel can reach several MHz, which makes high demands on the separation of pile-up pulses. For such applications we have built the GANDALF transient recorder with a resolution of 12bit@1GS/s and an analog bandwidth of 500 MHz. Signals are digitized and processed by fast algorithms to extract pulse arrival times and amplitudes in real-time and to generate experiment trigger signals. With up to 16 analog channels, deep memories and a high data rate interface, this 6U-VME64x/VXS module is not only a dead-time free digitization unit but also has huge numerical capabilities provided by the implementation of a Virtex5-SXT FPGA. Fast algorithms implemented in the FPGA may be used to disentangle possible pile-up pulses and...

  3. High-resolution X-ray television and high-resolution video recorders

    International Nuclear Information System (INIS)

    Haendle, J.; Horbaschek, H.; Alexandrescu, M.

    1977-01-01

    The improved transmission properties of the high-resolution X-ray television chain described here make it possible to transmit more information per television image. The resolution in the fluoroscopic image, which is visually determined, depends on the dose rate and the inertia of the television pick-up tube. This connection is discussed. In the last few years, video recorders have been increasingly used in X-ray diagnostics. The video recorder is a further quality-limiting element in X-ray television. The development of function patterns of high-resolution magnetic video recorders shows that this quality drop may be largely overcome. The influence of electrical band width and number of lines on the resolution in the X-ray television image stored is explained in more detail. (orig.) [de

  4. A multi-channel high-resolution time recorder system

    International Nuclear Information System (INIS)

    Zhang Lingyun; Yang Xiaojun; Song Kezhu; Wang Yanfang

    2004-01-01

    This paper introduces a multi-channel and high-speed time recorder system, which was originally designed to work in the experiments of quantum cryptography research. The novelty of the system is that all the hardware logic is performed by only one FPGA. The system can achieve several desirable features, such as simplicity, high resolution and high processing speed. (authors)

  5. Optimization of High-Resolution Continuous Flow Analysis for Transient Climate Signals in Ice Cores

    DEFF Research Database (Denmark)

    Bigler, Matthias; Svensson, Anders; Kettner, Ernesto

    2011-01-01

    Over the past two decades, continuous flow analysis (CFA) systems have been refined and widely used to measure aerosol constituents in polar and alpine ice cores in very high-depth resolution. Here we present a newly designed system consisting of sodium, ammonium, dust particles, and electrolytic...... meltwater conductivity detection modules. The system is optimized for high- resolution determination of transient signals in thin layers of deep polar ice cores. Based on standard measurements and by comparing sections of early Holocene and glacial ice from Greenland, we find that the new system features...

  6. High resolution deep level transient spectroscopy and process-induced defects in silicon

    International Nuclear Information System (INIS)

    Evans-Freeman, J.H.; Emiroglu, D.; Vernon-Parry, K.D.

    2004-01-01

    High resolution, or Laplace, deep level transient spectroscopy (LDLTS) enables the identification of very closely spaced energetic levels in a semiconductor bandgap. DLTS may resolve peaks with a separation of tens of electron volts, but LDLTS can resolve defect energy separations as low as a few MeV. In this paper, we present results from LDLTS applied to ion implantation-induced defects in silicon, with particular emphasis on characterisation of end-of-range interstitial type defects. Silicon was implanted with a variety of ions from mass 28 to 166. A combination of LDLTS and direct capture cross-section measurements was employed to show that electrically active small extended defects were present in the as-implanted samples. Larger dislocations were then generated in Si by oxygenation to act as a control sample. These stacking faults had typical lengths of microns, and their electrical activity was subsequently characterised by LDLTS. This was to establish the sensitivity of LDLTS to defects whose carrier capture is characterised by a non-exponential filling process and an evolving band structure as carrier capture proceeds. The LDLTS spectra show several components in capacitance transients originating from both the end-of-range defects, and the stacking faults, and also clearly show that the carrier emission rates reduce as these extended defects fill with carriers. The end-of-range defects and the stacking faults are shown to have the same electrical behaviour

  7. Inter- and intrarater reliability of the Chicago Classification in pediatric high-resolution esophageal manometry recordings

    NARCIS (Netherlands)

    Singendonk, M. M. J.; Smits, M. J.; Heijting, I. E.; van Wijk, M. P.; Nurko, S.; Rosen, R.; Weijenborg, P. W.; Abu-Assi, R.; Hoekman, D. R.; Kuizenga-Wessel, S.; Seiboth, G.; Benninga, M. A.; Omari, T. I.; Kritas, S.

    2015-01-01

    The Chicago Classification (CC) facilitates interpretation of high-resolution manometry (HRM) recordings. Application of this adult based algorithm to the pediatric population is unknown. We therefore assessed intra and interrater reliability of software-based CC diagnosis in a pediatric cohort.

  8. Inverse stochastic-dynamic models for high-resolution Greenland ice core records

    DEFF Research Database (Denmark)

    Boers, Niklas; Chekroun, Mickael D.; Liu, Honghu

    2017-01-01

    as statistical properties such as probability density functions, waiting times and power spectra, with no need for any external forcing. The crucial ingredients for capturing these properties are (i) high-resolution training data, (ii) cubic drift terms, (iii) nonlinear coupling terms between the 18O and dust......Proxy records from Greenland ice cores have been studied for several decades, yet many open questions remain regarding the climate variability encoded therein. Here, we use a Bayesian framework for inferring inverse, stochastic-dynamic models from 18O and dust records of unprecedented, subdecadal...

  9. Bivariable analysis of ventricular late potentials in high resolution ECG records

    International Nuclear Information System (INIS)

    Orosco, L; Laciar, E

    2007-01-01

    In this study the bivariable analysis for ventricular late potentials detection in high-resolution electrocardiographic records is proposed. The standard time-domain analysis and the application of the time-frequency technique to high-resolution ECG records are briefly described as well as their corresponding results. In the proposed technique the time-domain parameter, QRSD and the most significant time-frequency index, EN QRS are used like variables. A bivariable index is defined, that combines the previous parameters. The propose technique allows evaluating the risk of ventricular tachycardia in post-myocardial infarct patients. The results show that the used bivariable index allows discriminating between the patient's population with ventricular tachycardia and the subjects of the control group. Also, it was found that the bivariable technique obtains a good valuation as diagnostic test. It is concluded that comparatively, the valuation of the bivariable technique as diagnostic test is superior to that of the time-domain method and the time-frequency technique evaluated individually

  10. Inverse stochastic–dynamic models for high-resolution Greenland ice core records

    Directory of Open Access Journals (Sweden)

    N. Boers

    2017-12-01

    Full Text Available Proxy records from Greenland ice cores have been studied for several decades, yet many open questions remain regarding the climate variability encoded therein. Here, we use a Bayesian framework for inferring inverse, stochastic–dynamic models from δ18O and dust records of unprecedented, subdecadal temporal resolution. The records stem from the North Greenland Ice Core Project (NGRIP, and we focus on the time interval 59–22 ka b2k. Our model reproduces the dynamical characteristics of both the δ18O and dust proxy records, including the millennial-scale Dansgaard–Oeschger variability, as well as statistical properties such as probability density functions, waiting times and power spectra, with no need for any external forcing. The crucial ingredients for capturing these properties are (i high-resolution training data, (ii cubic drift terms, (iii nonlinear coupling terms between the δ18O and dust time series, and (iv non-Markovian contributions that represent short-term memory effects.

  11. Inverse stochastic-dynamic models for high-resolution Greenland ice core records

    Science.gov (United States)

    Boers, Niklas; Chekroun, Mickael D.; Liu, Honghu; Kondrashov, Dmitri; Rousseau, Denis-Didier; Svensson, Anders; Bigler, Matthias; Ghil, Michael

    2017-12-01

    Proxy records from Greenland ice cores have been studied for several decades, yet many open questions remain regarding the climate variability encoded therein. Here, we use a Bayesian framework for inferring inverse, stochastic-dynamic models from δ18O and dust records of unprecedented, subdecadal temporal resolution. The records stem from the North Greenland Ice Core Project (NGRIP), and we focus on the time interval 59-22 ka b2k. Our model reproduces the dynamical characteristics of both the δ18O and dust proxy records, including the millennial-scale Dansgaard-Oeschger variability, as well as statistical properties such as probability density functions, waiting times and power spectra, with no need for any external forcing. The crucial ingredients for capturing these properties are (i) high-resolution training data, (ii) cubic drift terms, (iii) nonlinear coupling terms between the δ18O and dust time series, and (iv) non-Markovian contributions that represent short-term memory effects.

  12. High-resolution record of pyrogenic polycyclic aromatic hydrocarbon deposition during the 20th century.

    Science.gov (United States)

    Lima, Ana Lúcia C; Eglinton, Timothy I; Reddy, Christopher M

    2003-01-01

    A high-resolution record of polycyclic aromatic hydrocarbon (PAH) deposition in Rhode Island over the past approximately 180 years was constructed using a sediment core from the anoxic Pettaquamscutt River basin. The record showed significantly more structure than has hitherto been reported and revealed four distinct maxima in PAH flux. The characteristic increase in PAH flux at the turn of the 20th century was captured in detail, leading to an initial maximum prior to the Great Depression. The overall peak in PAH flux in the 1950s was followed by a maximum that immediately preceded the 1973 Organization of Petroleum Exporting Countries (OPEC) oil embargo. During the most recent portion of the record, an abrupt increase in PAH flux between 1996 and 1999 has been found to follow a period of near constant fluxes. Because source-diagnostic ratios indicate that petrogenic inputs are minor throughout the record, these trends are interpreted in terms of past variations in the magnitude and type of combustion processes. For the most recent PAH maximum, energy consumption data suggest that diesel fuel combustion, and hence traffic of heavier vehicles, is the most probable cause for the increase in PAH flux. Systematic variations in the relative abundance of individual PAHs in conjunction with the above changes in flux are interpreted in relation to the evolution of combustion processes. Coronene, retene, and perylene are notable exceptions, exhibiting unique down-core profiles.

  13. Inverse transformation algorithm of transient electromagnetic field and its high-resolution continuous imaging interpretation method

    International Nuclear Information System (INIS)

    Qi, Zhipeng; Li, Xiu; Lu, Xushan; Zhang, Yingying; Yao, Weihua

    2015-01-01

    We introduce a new and potentially useful method for wave field inverse transformation and its application in transient electromagnetic method (TEM) 3D interpretation. The diffusive EM field is known to have a unique integral representation in terms of a fictitious wave field that satisfies a wave equation. The continuous imaging of TEM can be accomplished using the imaging methods in seismic interpretation after the diffusion equation is transformed into a fictitious wave equation. The interpretation method based on the imaging of a fictitious wave field could be used as a fast 3D inversion method. Moreover, the fictitious wave field possesses some wave field features making it possible for the application of a wave field interpretation method in TEM to improve the prospecting resolution.Wave field transformation is a key issue in the migration imaging of a fictitious wave field. The equation in the wave field transformation belongs to the first class Fredholm integration equation, which is a typical ill-posed equation. Additionally, TEM has a large dynamic time range, which also facilitates the weakness of this ill-posed problem. The wave field transformation is implemented by using pre-conditioned regularized conjugate gradient method. The continuous imaging of a fictitious wave field is implemented by using Kirchhoff integration. A synthetic aperture and deconvolution algorithm is also introduced to improve the interpretation resolution. We interpreted field data by the method proposed in this paper, and obtained a satisfying interpretation result. (paper)

  14. Stable isotope ratios in freshwater mussel shells as high resolution recorders of riverine environmental variation

    Science.gov (United States)

    Kukolich, S.; Kendall, C.; Dettman, D. L.

    2017-12-01

    The geochemical record stored in growth increments of freshwater mussel shells reveals annual to sub-annual changes in environmental conditions during the lifetime of the organism. The carbon, nitrogen, and oxygen stable isotope composition of aragonite shells responds to changes in water chemistry, temperature, streamflow, turbidity, growth rate, size, age, and reproduction. The goals of this study are to determine how stable isotopes can be used to reconstruct the conditions in which the mussels lived and to illuminate any vital effects that might obscure the isotopic record of those conditions. Previous research has suggested that annual δ13C values decrease in older freshwater mussel shells due to lower growth rates and greater incorporation of dietary carbon into the shell with increasing age. However, a high-resolution, seasonal investigation of δ13C, δ15N, and δ18O as they relate to organism age has not yet been attempted in freshwater mussels. A total of 28 Unionid mussels of three different species were collected live in 2011 in the Tennessee River near Paducah, Kentucky, USA. In this study, we analyzed the shell nacre and external organic layers for stable carbon, nitrogen, and oxygen isotope ratios, focusing on growth bands formed between 2006 and 2011. We present a time series of shell δ13C, δ18O, and δ15N values with monthly resolution. We also compare the shell-derived geochemical time series to a time series of the δ13C and δ15N of particulate organic matter, δ13C of DIC, δ18OWater, and water temperature in which the mussels lived. Results show that environmental factors such as water temperature and primary productivity dominate shell chemistry while animal age has little or no effect.

  15. Validation of criteria for the definition of transient lower esophageal sphincter relaxations using high-resolution manometry.

    Science.gov (United States)

    Roman, S; Holloway, R; Keller, J; Herbella, F; Zerbib, F; Xiao, Y; Bernard, L; Bredenoord, A J; Bruley des Varannes, S; Chen, M; Fox, M; Kahrilas, P J; Mittal, R K; Penagini, R; Savarino, E; Sifrim, D; Wu, J; Decullier, E; Pandolfino, J E; Mion, F

    2017-02-01

    Criteria for transient lower esophageal sphincter relaxations (TLESRs) are well-defined for Dentsleeve manometry. As high-resolution manometry (HRM) is now the gold standard to assess esophageal motility, our aim was to propose a consensus definition of TLESRs using HRM. Postprandial esophageal HRM combined with impedance was performed in 10 patients with gastroesophageal reflux disease. Transient lower esophageal sphincter relaxations identification was performed by 17 experts using a Delphi process. Four investigators then characterized TLESR candidates that achieved 100% agreement (TLESR events) and those that achieved less than 25% agreement (non-events) after the third round. Logistic regression and decision tree analysis were used to define optimal diagnostic criteria. All diagnostic criteria were more frequently encountered in the 57 TLESR events than in the 52 non-events. Crural diaphragm (CD) inhibition and LES relaxation duration >10 seconds had the highest predictive value to identify TLESR. Based on decision tree analysis, reflux on impedance, esophageal shortening, common cavity, upper esophageal sphincter relaxation without swallow and secondary peristalsis were alternate diagnostic criteria. Using HRM, TLESR might be defined as LES relaxation occurring in absence of swallowing, lasting more than 10 seconds and associated with CD inhibition. © 2016 John Wiley & Sons Ltd.

  16. Latest Holocene Climate Variability revealed by a high-resolution multiple Proxy Record off Lisbon (Portugal)

    Science.gov (United States)

    Abrantes, F.; Lebreiro, S.; Ferreira, A.; Gil, I.; Jonsdottir, H.; Rodrigues, T.; Kissel, C.; Grimalt, J.

    2003-04-01

    The North Atlantic Oscillation (NAO) is known to have a major influence on the wintertime climate of the Atlantic basin and surrounding countries, determining precipitation and wind conditions at mid-latitudes. A comparison of Hurrel's NAO index to the mean winter (January-March) discharge of the Iberian Tagus River reveals a good negative correlation to negative NAO, while the years of largest upwelling anomalies, as referred in the literature, appear to be in good agreement with positive NAO. On this basis, a better understanding of the long-term variability of the NAO and Atlantic climate variability can be gained from high-resolution climate records from the Lisbon area. Climate variability of the last 2,000 years is assessed through a multiple proxy study of sedimentary sequences recovered from the Tagus prodelta deposition center, off Lisbon (Western Iberia). Physical properties, XRF and magnetic properties from core logging, grain size, δ18O, TOC, CaCO3, total alkenones, n-alkanes, alkenone SST, diatoms, benthic and planktonic foraminiferal assemblage compositions and fluxes are the proxies employed. The age model for site D13902 is based on AMS C-14 dates from mollusc and planktonic foraminifera shells, the reservoir correction for which was obtained by dating 3 pre-bomb, mollusc shells from the study area. Preliminary results indicate a Little Ice Age (LIA - 1300 - 1600 AD) alkenone derived SSTs around 15 degC followed by a sharp and rapid increase towards 19 degC. In spite the strong variability observed for most records, this low temperature interval is marked by a general increase in organic carbon, total alkenone concentration, diatom and foraminiferal abundances, as well as an increase in the sediment fine fraction and XRF determined Fe content, pointing to important river input and higher productivity. The Medieval Warm Period (1080 - 1300 AD) is characterized by 17-18 degC SSTs, increased mean grain size, but lower magnetic susceptibility and Fe

  17. UDECON: deconvolution optimization software for restoring high-resolution records from pass-through paleomagnetic measurements

    Science.gov (United States)

    Xuan, Chuang; Oda, Hirokuni

    2015-11-01

    The rapid accumulation of continuous paleomagnetic and rock magnetic records acquired from pass-through measurements on superconducting rock magnetometers (SRM) has greatly contributed to our understanding of the paleomagnetic field and paleo-environment. Pass-through measurements are inevitably smoothed and altered by the convolution effect of SRM sensor response, and deconvolution is needed to restore high-resolution paleomagnetic and environmental signals. Although various deconvolution algorithms have been developed, the lack of easy-to-use software has hindered the practical application of deconvolution. Here, we present standalone graphical software UDECON as a convenient tool to perform optimized deconvolution for pass-through paleomagnetic measurements using the algorithm recently developed by Oda and Xuan (Geochem Geophys Geosyst 15:3907-3924, 2014). With the preparation of a format file, UDECON can directly read pass-through paleomagnetic measurement files collected at different laboratories. After the SRM sensor response is determined and loaded to the software, optimized deconvolution can be conducted using two different approaches (i.e., "Grid search" and "Simplex method") with adjustable initial values or ranges for smoothness, corrections of sample length, and shifts in measurement position. UDECON provides a suite of tools to view conveniently and check various types of original measurement and deconvolution data. Multiple steps of measurement and/or deconvolution data can be compared simultaneously to check the consistency and to guide further deconvolution optimization. Deconvolved data together with the loaded original measurement and SRM sensor response data can be saved and reloaded for further treatment in UDECON. Users can also export the optimized deconvolution data to a text file for analysis in other software.

  18. High-resolution conodont oxygen isotope record of Ordovician climate change

    Science.gov (United States)

    Chen, J.; Chen, Z.; Algeo, T. J.

    2013-12-01

    The Ordovician Period was characterized by several major events, including a prolonged 'super greenhouse' during the Early Ordovician, the 'Great Ordovician Biodiversification Event (GOBE)' of the Middle and early Late Ordovician, and the Hirnantian ice age and mass extinction of the latest Ordovician (Webby et al., 2004, The Great Ordovician Biodiversification Event, Columbia University Press). The cause of the rapid diversification of marine invertebrates during the GOBE is not clear, however, and several scenarios have been proposed including widespread development of shallow cratonic seas, strong magmatic and tectonic activity, and climate moderation. In order to investigate relationships between climate change and marine ecosystem evolution during the Ordovician, we measured the oxygen isotopic composition of single coniform conodonts using a Cameca secondary ion mass spectrometer. Our δ18O profile shows a shift at the Early/Middle Ordovician transition that is indicative of a rapid 6 to 8 °C cooling. This cooling event marks the termination of the Early Ordovician 'super greenhouse' and may have established cooler tropical seawater temperatures that were more favorable for invertebrate animals, setting the stage for the GOBE. Additional cooling episodes occurred during the early Sandbian, early Katian, and Hirnantian, the last culminating in a short-lived (extinction. Our results differ from those of Trotter et al. (2008, 'Did cooling oceans trigger Ordovician biodiversification? Evidence from conodont thermometry,' Science 321:550-554). Instead of a slow, protracted cooling through the Early and Middle Ordovician, our high-resolution record shows that cooling occurred in several discrete steps, with the largest step being at the Early/Middle Ordovician transition.

  19. Late Quaternary high resolution micropaleontological and sedimentological records in the Gulf of Cadiz.

    Science.gov (United States)

    Balestra, B.; Ducassou, E.; Zarikian, C.; Bout-Roumazeilles, V.; Flores, J. A.; Paytan, A.

    2017-12-01

    We present preliminary micropaleontological and sedimentological data from IODP Site U1390 (Expedition 339), located in the central middle slope of the Gulf of Cadiz, since the last glaciation. This site has been targeted for reconstruction of regional paleo-circulation as it shows particularly high sedimentation rates, throughout the Holocene and the Last Glacial Maximum (LGM). We use micropaleontological and sedimentological proxies to understand the bottom current variations through time and the ecological conditions at the sea surface (planktonic foraminifer, pteropod and nannofossil assemblages), and the sea bottom (ostracod assemblages). Eleven samples, chosen at transitions of planktonic foraminifer assemblages, have been dated by AMS radiocarbon analyses. Preliminary results from benthic ostracod assemblages show variations in bottom water ventilation and food supply. Planktonic foraminifer assemblages clearly show the well-known cold events of this period such as the Younger Dryas and Heinrich stadial associated to coarser sediment, and warmer phases such as the Bölling-Allerød associated to muddy sediment. Other bio-events within the Holocene period are also recorded. The preservation of the coccolithophore assemblages is good to moderate. Coccolith abundances (expressed in coccoliths/gr of sediment) show higher values during the Holocene and generally are like assemblages previously reported for the same area. Implications for characterization of the Holocene, the last termination and LGM ecological conditions at high resolution and their potential fluctuations (i.e. amplitude and magnitude) under the influence of the lower core of the Mediterranean Outflow Water (MOW), with this multi proxy approach based on sedimentological, and paleontological data will be discussed.

  20. High resolution record of the Last Glacial Maximum in eastern Australia

    Science.gov (United States)

    Petherick, Lynda; Moss, Patrick; McGowan, Hamish

    2010-05-01

    A continuous, high resolution (average ca. 22 year) record encompassing the Last Glacial Maximum (LGM) has been developed using multiple proxies (aeolian sediment flux, grain size, pollen and charcoal) in lake sediment from Tortoise Lagoon (TOR), North Stradbroke Island, Queensland, Australia. The presence of Asteraceae tubilifloreae and spineless Asteraceae (common indicators of glacial conditions in Australia) at TOR indicates significantly cooler temperatures (mean annual temperature up to 6oC lower than today). In addition to the palaeoclimatic reconstruction, a record of palaeodust transport pathways for eastern Australia was developed using ICP-MS trace element analysis and geochemical "fingerprinting" of TOR aeolian sediment to continental dust source areas. Vectors between dominant dust source areas and North Stradbroke Island allowed the reconstruction of the position and intensity of LGM dust transport pathways. Furthermore, changes in likely synpotic scale conditions can be postulated based on the position of the dust transport corridors. Similarities between the vegetation at TOR during the LGM and that at temperate sites e.g. Caledonia Fen, Victoria (Kershaw et al. 2007), Redhead Lagoon, New South Wales (Williams et al. 2006) and Barrington Tops, New South Wales (Sweller and Martin 2001) suggests that this record reflects regional conditions across southeastern Australia. The TOR record also correlates well with that from nearby Native Companion Lagoon which suggests that the LGM was actually an extended period of ca. 8 - 10 kyr, characterised by 2 periods of increased aridity (ca. 30 - 26.5 kyr and 21 - 19.5 kyr) (Petherick et al. 2008). A growing number of records from across the Southern Hemisphere e.g. New Zealand (Suggate and Almond 2003; Alloway et al. 2007; Newnham et al. 2007), Chile (Denton et al. 1999), Antarctica (Röthlisberger et al. 2002; EPICA 2006) and Australia (Smith 2009) also show evidence that the LGM encompassed a longer period of

  1. High-resolution records of non-dipole variations in the intensity of the Earth's magnetic field

    NARCIS (Netherlands)

    de Groot, L.V.

    2013-01-01

    Our understanding of the short-term behavior of the Earth’s magnetic field is currently mainly hampered by a lack of high-resolution records of geomagnetic intensity variations that are well distributed over the globe and cover the same timespan. Over the past decades many efforts have been made to

  2. High-resolution esophageal pressure topography is superior to conventional sleeve manometry for the detection of transient lower esophageal sphincter relaxations associated with a reflux event

    NARCIS (Netherlands)

    Rohof, W. O. A.; Boeckxstaens, G. E. E.; Hirsch, D. P.

    2011-01-01

    Transient lower esophageal sphincter relaxations (TLESRs) are the main mechanism underlying gastro-esophageal reflux and are detected during manometric studies using well defined criteria. Recently, high-resolution esophageal pressure topography (HREPT) has been introduced and is now considered as

  3. Optimum aberration coefficients for recording high-resolution off-axis holograms in a Cs-corrected TEM

    Energy Technology Data Exchange (ETDEWEB)

    Linck, Martin, E-mail: linck@ceos-gmbh.de [CEOS GmbH, Englerstr. 28, D-69126 Heidelberg (Germany)

    2013-01-15

    Amongst the impressive improvements in high-resolution electron microscopy, the Cs-corrector also has significantly enhanced the capabilities of off-axis electron holography. Recently, it has been shown that the signal above noise in the reconstructable phase can be significantly improved by combining holography and hardware aberration correction. Additionally, with a spherical aberration close to zero, the traditional optimum focus for recording high-resolution holograms ('Lichte's defocus') has become less stringent and both, defocus and spherical aberration, can be selected freely within a certain range. This new degree of freedom can be used to improve the signal resolution in the holographically reconstructed object wave locally, e.g. at the atomic positions. A brute force simulation study for an aberration corrected 200 kV TEM is performed to determine optimum values for defocus and spherical aberration for best possible signal to noise in the reconstructed atomic phase signals. Compared to the optimum aberrations for conventional phase contrast imaging (NCSI), which produce 'bright atoms' in the image intensity, the resulting optimum values of defocus and spherical aberration for off-axis holography enable 'black atom contrast' in the hologram. However, they can significantly enhance the local signal resolution at the atomic positions. At the same time, the benefits of hardware aberration correction for high-resolution off-axis holography are preserved. It turns out that the optimum is depending on the object and its thickness and therefore not universal. -- Highlights: Black-Right-Pointing-Pointer Optimized aberration parameters for high-resolution off-axis holography. Black-Right-Pointing-Pointer Simulation and analysis of noise in high-resolution off-axis holograms. Black-Right-Pointing-Pointer Improving signal resolution in the holographically reconstructed phase shift. Black-Right-Pointing-Pointer Comparison of &apos

  4. Optimum aberration coefficients for recording high-resolution off-axis holograms in a Cs-corrected TEM

    International Nuclear Information System (INIS)

    Linck, Martin

    2013-01-01

    Amongst the impressive improvements in high-resolution electron microscopy, the Cs-corrector also has significantly enhanced the capabilities of off-axis electron holography. Recently, it has been shown that the signal above noise in the reconstructable phase can be significantly improved by combining holography and hardware aberration correction. Additionally, with a spherical aberration close to zero, the traditional optimum focus for recording high-resolution holograms (“Lichte's defocus”) has become less stringent and both, defocus and spherical aberration, can be selected freely within a certain range. This new degree of freedom can be used to improve the signal resolution in the holographically reconstructed object wave locally, e.g. at the atomic positions. A brute force simulation study for an aberration corrected 200 kV TEM is performed to determine optimum values for defocus and spherical aberration for best possible signal to noise in the reconstructed atomic phase signals. Compared to the optimum aberrations for conventional phase contrast imaging (NCSI), which produce “bright atoms” in the image intensity, the resulting optimum values of defocus and spherical aberration for off-axis holography enable “black atom contrast” in the hologram. However, they can significantly enhance the local signal resolution at the atomic positions. At the same time, the benefits of hardware aberration correction for high-resolution off-axis holography are preserved. It turns out that the optimum is depending on the object and its thickness and therefore not universal. -- Highlights: ► Optimized aberration parameters for high-resolution off-axis holography. ► Simulation and analysis of noise in high-resolution off-axis holograms. ► Improving signal resolution in the holographically reconstructed phase shift. ► Comparison of “black” and “white” atom contrast in off-axis holograms.

  5. High resolution magnetic force microscopy: instrumentation and application for recording media

    NARCIS (Netherlands)

    Porthun, Steffen; Porthun, S.

    This thesis describes aspects of the use of magnetic force microscopy for the study of magnetic recording media. The maximum achievable storage density in magnetic recording is limited by the magnetic reversal behaviour of the medium and by the stability of the written information. The shape and

  6. Early to Middle Jurassic palaeoenvironmental changes: High resolution δ13C and δ18O records from the UK

    DEFF Research Database (Denmark)

    Korte, Christoph; Hesselbo, Stephen; Ullmann, Clemens Vinzenz

    Low-Mg-calcite fossils, such as bivalves, belemnites and brachiopods, and bulk rocks have been extensively utilized to reconstruct past seawater chemistry and paleoenviron¬mental changes. Recent work on major bioevents demonstrated that particularly higher resolution stable isotope records...... are necessary to reveal short-term paleoenviron¬mental fluctuations and, in addition, to discover its causes. Here we present a new high resolution carbon and oxygen isotope dataset generated from low-Mg-calcite fossils, fossil wood and bulk rocks collected from Early to Middle Jurassic marine successions...

  7. High resolution climate reconstructions of recent warming using instrumental and ice core records from coastal Antarctica

    Digital Repository Service at National Institute of Oceanography (India)

    Thamban, M.; Naik, S.S.; Laluraj, C.M.; Ravindra, R.

    for the past 4 years (Thamban et al., 2006). Chronological control for the IND-25/B5 ice core was based on multiple and complimentary methods: (i) atomic bomb (Tritium) markers; (ii) annual layer counting using stable isotope records; and (iii) volcanic...

  8. High resolution Holocene paleomagnetic secular variation records from Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Usapkar, A.; Dewangan, P.; Badesab, F.K.; Mazumdar, A.; Ramprasad, T.; Krishna, K.S.; Basavaiah, N.

    /8 probably due to local effects. Paleoinclination records of MD161/8, MD161/11 and MD161/13 show a low between ~2.4 and 2.0 cal. kyr BP, an increase between 2.0 and 1.4 cal. kyr BP and a decrease towards the present. To varying degrees these trends can...

  9. Fluvial-Deltaic Strata as a High-Resolution Recorder of Fold Growth and Fault Slip

    Science.gov (United States)

    Anastasio, D. J.; Kodama, K. P.; Pazzaglia, F. P.

    2008-12-01

    Fluvial-deltaic systems characterize the depositional record of most wedge-top and foreland basins, where the synorogenic stratigraphy responds to interactions between sediment supply driven by tectonic uplift, climate modulated sea level change and erosion rate variability, and fold growth patterns driven by unsteady fault slip. We integrate kinematic models of fault-related folds with growth strata and fluvial terrace records to determine incremental rates of shortening, rock uplift, limb tilting, and fault slip with 104-105 year temporal resolution in the Pyrenees and Apennines. At Pico del Aguila anticline, a transverse dècollement fold along the south Pyrenean mountain front, formation-scale synorogenic deposition and clastic facies patterns in prodeltaic and slope facies reflect tectonic forcing of sediment supply, sea level variability controlling delta front position, and climate modulated changes in terrestrial runoff. Growth geometries record a pinned anticline and migrating syncline hinges during folding above the emerging Guarga thrust sheet. Lithologic and anhysteretic remanent magnetization (ARM) data series from the Eocene Arguis Fm. show cyclicity at Milankovitch frequencies allowing detailed reconstruction of unsteady fold growth. Multiple variations in limb tilting rates from roof ramp and basal dècollement. Along the northern Apennine mountain front, the age and geometry of strath terraces preserved across the Salsomaggiore anticline records the Pleistocene-Recent kinematics of the underlying fault-propagation fold as occurring with a fixed anticline hinge, a rolling syncline hinge, and along-strike variations in uplift and forelimb tilting. The uplifted intersection of terrace deposits documents syncline axial surface migration and underlying fault-tip propagation at a rate of ~1.4 cm/yr since the Middle Pleistocene. Because this record of fault slip coincides with the well-known large amplitude oscillations in global climate that contribute

  10. High-resolution carbon dioxide concentration record 650,000-800,000 years before present

    DEFF Research Database (Denmark)

    Lüthi, Dieter; Le Floch, Martine; Bereiter, Bernhard

    2008-01-01

    Changes in past atmospheric carbon dioxide concentrations can be determined by measuring the composition of air trapped in ice cores from Antarctica. So far, the Antarctic Vostok and EPICA Dome C ice cores have provided a composite record of atmospheric carbon dioxide levels over the past 650......,000 years. Here we present results of the lowest 200 m of the Dome C ice core, extending the record of atmospheric carbon dioxide concentration by two complete glacial cycles to 800,000 yr before present. From previously published data and the present work, we find that atmospheric carbon dioxide...... is strongly correlated with Antarctic temperature throughout eight glacial cycles but with significantly lower concentrations between 650,000 and 750,000 yr before present. Carbon dioxide levels are below 180 parts per million by volume (p.p.m.v.) for a period of 3,000 yr during Marine Isotope Stage 16...

  11. High-resolution record of Northern Hemisphere climate extending into the last interglacial period

    DEFF Research Database (Denmark)

    North Greenland Ice Core Project members; Andersen, Katrine K.; Azuma, N.

    2004-01-01

    Two deep ice cores from central Greenland, drilled in the 1990s, have played a key role in climate reconstructions of the Northern Hemisphere, but the oldest sections of the cores were disturbed in chronology owing to ice folding near the bedrock. Here we present an undisturbed climate record from...... the initiation of the last glacial period. Our record reveals a hitherto unrecognized warm period initiated by an abrupt climate warming about 115,000 years ago, before glacial conditions were fully developed. This event does not appear to have an immediate Antarctic counterpart, suggesting that the climate see......-saw between the hemispheres (which dominated the last glacial period) was not operating at this time....

  12. High-resolution carbon dioxide concentration record 650,000-800,000 years before present

    Energy Technology Data Exchange (ETDEWEB)

    Luthi, D; Bereiter, B; Blunier, T; Siegenthaler, U; Kawamura, K; Stocker, T F [Climate and Environm. Physics, Physics Inst., Univ. Bern, CH-3012 Bern, (Switzerland); Luthi, D; Bereiter, B; Blunier, T; Siegenthaler, U; Kawamura, K; Stocker, T F [Oeschger Centre for Climate Change Research, Univ. Bern, CH-3012 Bern, (Switzerland); Le Floch, M; Barnola, J M; Raynaud, D [LGGE, CNRS-Univ. Grenoble 1, F-38402 Saint Martin d' Heres, (France); Jouzel, J [Inst. Pierre Simon Laplace, LSCE, CEA-CNRS-Universite Versailles-Saint Quentin, CEA Saclay, F-91191 Gif sur Yvette (France); Fischer, H [Alfred Wegener Inst. for Polar and Maine Research, D-27568 Bremerhaven, (Germany)

    2008-07-01

    Changes in past atmospheric carbon dioxide concentrations can be determined by measuring the composition of air trapped in ice cores from Antarctica. So far, the Antarctic Vostok and EPICA Dome C ice cores have provided a composite record of atmospheric carbon dioxide levels over the past 650,000 years. Here we present results of the lowest 200 m of the Dome C ice core, extending the record of atmospheric carbon dioxide concentration by two complete glacial cycles to 800,000 yr before present. From previously published data and the present work, we find that atmospheric carbon dioxide is strongly correlated with Antarctic temperature throughout eight glacial cycles but with significantly lower concentrations between 650,000 and 750,000 yr before present. Carbon dioxide levels are below 180 parts per million by volume (p.p.m.v.) for a period of 3,000 yr during Marine Isotope Stage 16, possibly reflecting more pronounced oceanic carbon storage. We report the lowest carbon dioxide concentration measured in an ice core, which extends the pre-industrial range of carbon dioxide concentrations during the late Quaternary by about 10 p.p.m.v. to 172-300 p.p.m.v. (authors)

  13. Techniques for Handling Channeling in High Resolution Fourier Transform Spectra Recorded with Synchrotron Sources

    International Nuclear Information System (INIS)

    Ibrahim, Amr; PredoiCross, Adriana; Teillet, P. M.

    2010-01-01

    Seven different techniques in dealing the problem of channel spectra in Fourier transform Spectroscopy utilizing synchrotron source were examined and compared. Five of these techniques deal with the artifacts (spikes) in the recorded interferogram which in turn result in channel spectra within the spectral domain. Such interferogram editing method include replacing these spikes with zeros, straight line, fitted polynomial curve, rescaled spike and spike reduced with Gauss Function. Another two techniques try to target this issue in the spectral domain instead by either generating a synthetic background simulating the channels or measuring the channels parameters (amplitude, spacing and phase) to use in the spectral fitting program. Results showed spectral domain techniques produces higher quality results in terms of signal to noise and fitting residual. The effect of each method on the line parameters such as position, intensity are air broadening are also measured and discussed.

  14. Plio-Pleistocene climate sensitivity evaluated using high-resolution CO2 records

    Science.gov (United States)

    Martínez-Botí, M. A.; Foster, G. L.; Chalk, T. B.; Rohling, E. J.; Sexton, P. F.; Lunt, D. J.; Pancost, R. D.; Badger, M. P. S.; Schmidt, D. N.

    2015-02-01

    Theory and climate modelling suggest that the sensitivity of Earth's climate to changes in radiative forcing could depend on the background climate. However, palaeoclimate data have thus far been insufficient to provide a conclusive test of this prediction. Here we present atmospheric carbon dioxide (CO2) reconstructions based on multi-site boron-isotope records from the late Pliocene epoch (3.3 to 2.3 million years ago). We find that Earth's climate sensitivity to CO2-based radiative forcing (Earth system sensitivity) was half as strong during the warm Pliocene as during the cold late Pleistocene epoch (0.8 to 0.01 million years ago). We attribute this difference to the radiative impacts of continental ice-volume changes (the ice-albedo feedback) during the late Pleistocene, because equilibrium climate sensitivity is identical for the two intervals when we account for such impacts using sea-level reconstructions. We conclude that, on a global scale, no unexpected climate feedbacks operated during the warm Pliocene, and that predictions of equilibrium climate sensitivity (excluding long-term ice-albedo feedbacks) for our Pliocene-like future (with CO2 levels up to maximum Pliocene levels of 450 parts per million) are well described by the currently accepted range of an increase of 1.5 K to 4.5 K per doubling of CO2.

  15. Plio-Pleistocene climate sensitivity evaluated using high-resolution CO2 records.

    Science.gov (United States)

    Martínez-Botí, M A; Foster, G L; Chalk, T B; Rohling, E J; Sexton, P F; Lunt, D J; Pancost, R D; Badger, M P S; Schmidt, D N

    2015-02-05

    Theory and climate modelling suggest that the sensitivity of Earth's climate to changes in radiative forcing could depend on the background climate. However, palaeoclimate data have thus far been insufficient to provide a conclusive test of this prediction. Here we present atmospheric carbon dioxide (CO2) reconstructions based on multi-site boron-isotope records from the late Pliocene epoch (3.3 to 2.3 million years ago). We find that Earth's climate sensitivity to CO2-based radiative forcing (Earth system sensitivity) was half as strong during the warm Pliocene as during the cold late Pleistocene epoch (0.8 to 0.01 million years ago). We attribute this difference to the radiative impacts of continental ice-volume changes (the ice-albedo feedback) during the late Pleistocene, because equilibrium climate sensitivity is identical for the two intervals when we account for such impacts using sea-level reconstructions. We conclude that, on a global scale, no unexpected climate feedbacks operated during the warm Pliocene, and that predictions of equilibrium climate sensitivity (excluding long-term ice-albedo feedbacks) for our Pliocene-like future (with CO2 levels up to maximum Pliocene levels of 450 parts per million) are well described by the currently accepted range of an increase of 1.5 K to 4.5 K per doubling of CO2.

  16. A high-resolution, 60 kyr record of the relative geomagnetic field intensity from Lake Towuti, Indonesia

    Science.gov (United States)

    Kirana, Kartika Hajar; Bijaksana, Satria; King, John; Tamuntuan, Gerald Hendrik; Russell, James; Ngkoimani, La Ode; Dahrin, Darharta; Fajar, Silvia Jannatul

    2018-02-01

    Past changes in the Earth's magnetic field can be highlighted through reconstructions of magnetic paleointensity. Many magnetic field variation features are global, and can be used for the detailed correlation and dating of sedimentary records. On the other hand, sedimentary magnetic records also exhibit features on a regional, rather than a global scale. Therefore, the development of regional scale magnetic field reconstructions is necessary to optimize magnetic paleointensity dating. In this paper, a 60 thousand year (kyr) paleointensity record is presented, using the core TOW10-9B of Lake Towuti, located in the island of Sulawesi, Indonesia, as a part of the ongoing research towards understanding the Indonesian environmental history, and reconstructing a high-resolution regional magnetic record from dating the sediments. Located in the East Sulawesi Ophiolite Belt, the bedrock surrounding Lake Towuti consists of ultramafic rocks that render the lake sediments magnetically strong, creating challenges in the reconstruction of the paleointensity record. These sediment samples were subject to a series of magnetic measurements, followed by testing the obtained paleointensity records resulting from normalizing natural remanent magnetization (NRM) against different normalizing parameters. These paleointensity records were then compared to other regional, as well as global, records of magnetic paleointensity. The results show that for the magnetically strong Lake Towuti sediments, an anhysteretic remanent magnetization (ARM) is the best normalizer. A series of magnetic paleointensity excursions are observed during the last 60 kyr, including the Laschamp excursion at 40 kyr BP, that provide new information about the magnetic history and stratigraphy of the western tropical Pacific region. We conclude that the paleointensity record of Lake Towuti is reliable and in accordance with the high-quality regional and global trends.

  17. A 40 ka high-resolution soil carbonate record from southern Utah: proxy development, paleohydrology, and paleoecology

    Science.gov (United States)

    Huth, T.; Cerling, T. E.; Marchetti, D. W.; Fernandez, D. P.; Mackey, G. N., III; Bowling, D. R.; Passey, B. H.

    2017-12-01

    Terrestrial paleoclimate records are critically important for testing hypotheses of climate dynamics and verifying climate simulations. However, unlike their oceanic counterparts, terrestrial records are short, more commonly discontinuous, and require specific geographic conditions not necessarily ideal for proposed questions (e.g., speleothem records must come from wherever a cave occurs). We instead utilize laminated soil carbonate rinds as a high resolution (100s yr) paleoclimate archive. Soil carbonate rinds can represent 10s-100s kyr, are apparently continuous over relevant timescales, maintain stratigraphic order, and are common in arid and semi-arid regions. We demonstrate the utility of this methodology at Torrey, Utah which is at the northern edge of the North American Monsoon (NAM). Sample rinds form on the bottom of large (≈1 m) boulders. The rinds are 0.5-2 cm thick and have visually and microscopically identifiable stratigraphy. Radiocarbon dates are in order and suggest a nearly constant growth rate from ≈40 ka to 3 ka, when the record ends. However, the pendants have significant pore space, so secondary carbonate has the potential to bias sample ages to be too young by 100s-1000s years. Precise sampling may be able to mitigate this bias. In spite of the potential secondary carbonate bias, δ13C and δ18O analyses show trends consistent with regional records. Secondary carbonate is therefore a concern, but apparently does not overpower the primary isotopic signals. A calibration study identified soil carbonate formation during the peak growing season (i.e., JAS, during the NAM), so we interpret our records as summer signals modulated by soil `memory' effects. The δ18O record has low variability (±0.5 ‰) but mimics regional NAM records, suggesting similar climate drivers as far north as Utah. The δ13C record shows some correlation with δ18O, which is reasonable given that the strength of the NAM can drive ecologic responses. However, the data

  18. Century-scale high-resolution black carbon records in sediment cores from the South Yellow Sea, China

    Science.gov (United States)

    Xu, Xiaoming; Hong, Yuehui; Zhou, Qianzhi; Liu, Jinzhong; Yuan, Lirong; Wang, Jianghai

    2018-01-01

    Black carbon (BC) has received increasing attention in the last 20 years because it is not only an absorbent of toxic pollutants but also a greenhouse substance, preserving fire-history records, and more importantly, acting as an indicator of biogeochemical cycles and global changes. By adopting an improved chemothermal oxidation method (WXY), this study reconstructed the century-scale high-resolution records of BC deposition from two fine-grained sediment cores collected from the Yellow Sea Cold Water Mass in the South Yellow Sea. The BC records were divided into five stages, which exhibited specific sequences with three BC peaks at approximately 1891, 1921, and 2007 AD, representing times at which the first heavy storms appeared just after the termination of long-term droughts. The significant correlation between the times of the BC peaks in the cores and heavy storms in the area of the Huanghe (Yellow) River demonstrated that BC peaks could result from markedly strengthened sedimentation due to surface runoff, which augmented the atmospheric deposition. Stable carbon isotope analysis indicated that the evident increase in carbon isotope ratios of BC in Stage 5 might have resulted from the input of weathered rock-derived graphitic carbon cardinally induced by the annual anthropogenic modulation of water-borne sediment in the Huanghe River since 2005 AD. Numerical calculations demonstrated that the input fraction of graphitic carbon was 22.97% for Stage 5, whereas no graphitic carbon entered during Stages 1 and 3. The obtained data provide new and important understanding of the source-sink history of BC in the Yellow Sea.

  19. New continuous recording procedure of holographic information on transient phenomena

    Science.gov (United States)

    Nagayama, Kunihito; Nishihara, H. Keith; Murakami, Terutoshi

    1992-09-01

    A new method for continuous recording of holographic information, 'streak holography,' is proposed. This kind of record can be useful for velocity and acceleration measurement as well as for observing a moving object whose trajectory cannot be predicted in advance. A very high speed camera system has been designed and constructed for streak holography. A ring-shaped 100-mm-diam film has been cut out from the high-resolution sheet film and mounted on a thin duralmin disk, which has been driven to rotate directly by an air-turbine spindle. Attainable streak velocity is 0.3 mm/microsecond(s) . A direct film drive mechanism makes it possible to use a relay lens system of extremely small f number. The feasibility of the camera system has been demonstrated by observing several transient events, such as the forced oscillation of a wire and the free fall of small glass particles, using an argon-ion laser as a light source.

  20. Holocene vegetation and climate changes in the central Mediterranean inferred from a high-resolution marine pollen record (Adriatic Sea

    Directory of Open Access Journals (Sweden)

    N. Combourieu-Nebout

    2013-09-01

    Full Text Available The high-resolution multiproxy study of the Adriatic marine core MD 90-917 provides new insights to reconstruct vegetation and regional climate changes over the southcentral Mediterranean during the Younger Dryas (YD and Holocene. Pollen records show the rapid forest colonization of the Italian and Balkan borderlands and the gradual installation of the Mediterranean association during the Holocene. Quantitative estimates based on pollen data provide Holocene precipitations and temperatures in the Adriatic Sea using a multi-method approach. Clay mineral ratios from the same core reflect the relative contributions of riverine (illite and smectite and eolian (kaolinite contributions to the site, and thus act as an additional proxy with which to evaluate precipitation changes in the Holocene. Vegetation climate reconstructions show the response to the Preboreal oscillation (PBO, most likely driven by changes in temperature and seasonal precipitation, which is linked to increasing river inputs from Adriatic rivers recorded by increase in clay mineral contribution to marine sediments. Pollen-inferred temperature declines during the early–mid Holocene, then increases during the mid–late Holocene, similar to southwestern Mediterranean climatic patterns during the Holocene. Several short vegetation and climatic events appear in the record, indicating the sensitivity of vegetation in the region to millennial-scale variability. Reconstructed summer precipitation shows a regional maximum (170–200 mm between 8000 and 7000 similar to the general pattern across southern Europe. Two important shifts in vegetation occur at 7700 cal yr BP (calendar years before present and between 7500 and 7000 cal yr BP and are correlated with increased river inputs around the Adriatic Basin respectively from the northern (7700 event and from the central Adriatic borderlands (7500–7000 event. During the mid-Holocene, the wet summers lead to permanent moisture all year

  1. High resolution geochemical proxy record of the last 600yr in a speleothem from the northwest Iberian Peninsula

    Science.gov (United States)

    Iglesias González, Miguel; Pisonero, Jorge; Cheng, Hai; Edwards, R. Lawrence; Stoll, Heather

    2017-04-01

    In meteorology and climatology, the instrumental period is the period where we have measured directly by instrumentation, different meteorological data along the surface which allow us to determinate the evolution of the climate during the last 150 years over the world. At the beginning, the density of this data were very low, so we have to wait until the last 75-100 years to have a good network in most of the parts of the surface. This time period is very small if we want to analyze the relationship between geochemical and instrumental variability in any speleothem. So a very high resolution data is needed to determinate the connection between both of them in the instrumental period, to try to determinate de evolution of climate in the last 600 years. Here we present a high resolution speleothem record from a cave located in the middle of the Cantabrian Mountains without any anthropologic influence and with no CO2 seasonal variability. This 600yr stalagmite, dated with U/Th method with a growth rate from 100 to 200 micrometers/yr calculated with Bchron model, provide us accurate information of the climate conditions near the cave. Trace elements are analyzed at 8 micrometers intervals by Laser Ablation ICP-MS which resolves even monthly resolution during the last 600 years with special attention with Sr, Mg, Al and Si. This data, without seasonal variability and with the presence of a river inside the cave, give us very valuable information about the extreme flood events inside the cave during the whole period, which is related with the precipitations and the snow fusion events outside the cave. We identify more extremely flood events during the Little Ice Age than in the last 100yr. As well, we have trace elements data with spatial resolution of 0.2mm analyzed with ICP-AES which allow us to compare the geochemical variability with both technics. We also analyze stable isotope d13C and d18O with a spatial resolution of 0.2mm, so we are able to identify variations

  2. Prototype of a transient waveform recording ASIC

    Science.gov (United States)

    Qin, J.; Zhao, L.; Cheng, B.; Chen, H.; Guo, Y.; Liu, S.; An, Q.

    2018-01-01

    The paper presents the design and measurement results of a transient waveform recording ASIC based on the Switched Capacitor Array (SCA) architecture. This 0.18 μm CMOS prototype device contains two channels and each channel employs a SCA of 128 samples deep, a 12-bit Wilkinson ADC and a serial data readout. A series of tests have been conducted and the results indicate that: a full 1 V signal voltage range is available, the input analog bandwidth is approximately 450 MHz and the sampling speed is adjustable from 0.076 to 3.2 Gsps (Gigabit Samples Per Second). For precision waveform timing extraction, careful calibration of timing intervals between samples is conducted to improve the timing resolution of such chips, and the timing precision of this ASIC is proved to be better than 15 ps RMS.

  3. Intra- and interrater reliability of the Chicago Classification of achalasia subtypes in pediatric high-resolution esophageal manometry (HRM) recordings.

    Science.gov (United States)

    Singendonk, M M J; Rosen, R; Oors, J; Rommel, N; van Wijk, M P; Benninga, M A; Nurko, S; Omari, T I

    2017-11-01

    Subtyping achalasia by high-resolution manometry (HRM) is clinically relevant as response to therapy and prognosis have shown to vary accordingly. The aim of this study was to assess inter- and intrarater reliability of diagnosing achalasia and achalasia subtyping in children using the Chicago Classification (CC) V3.0. Six observers analyzed 40 pediatric HRM recordings (22 achalasia and 18 non-achalasia) twice by using dedicated analysis software (ManoView 3.0, Given Imaging, Los Angeles, CA, USA). Integrated relaxation pressure (IRP4s), distal contractile integral (DCI), intrabolus pressurization pattern (IBP), and distal latency (DL) were extracted and analyzed hierarchically. Cohen's κ (2 raters) and Fleiss' κ (>2 raters) and the intraclass correlation coefficient (ICC) were used for categorical and ordinal data, respectively. Based on the results of dedicated analysis software only, intra- and interrater reliability was excellent and moderate (κ=0.89 and κ=0.52, respectively) for differentiating achalasia from non-achalasia. For subtyping achalasia, reliability decreased to substantial and fair (κ=0.72 and κ=0.28, respectively). When observers were allowed to change the software-driven diagnosis according to their own interpretation of the manometric patterns, intra- and interrater reliability increased for diagnosing achalasia (κ=0.98 and κ=0.92, respectively) and for subtyping achalasia (κ=0.79 and κ=0.58, respectively). Intra- and interrater agreement for diagnosing achalasia when using HRM and the CC was very good to excellent when results of automated analysis software were interpreted by experienced observers. More variability was seen when relying solely on the software-driven diagnosis and for subtyping achalasia. Therefore, diagnosing and subtyping achalasia should be performed in pediatric motility centers with significant expertise. © 2017 John Wiley & Sons Ltd.

  4. High - Resolution SST Record Based on Mg/Ca Ratios of Late Holocene Planktonic Foraminifers From the Great Bahama Bank

    Science.gov (United States)

    Mueller, A.; Reijmer, J. J.; Roth, S.

    2001-12-01

    We analyzed five different planktic foraminifera species in the high resolution core MD 992201 off the Great Bahama Bank (79° 16.34 W; 25° 53.49 N) in 290 m water depth. This 38.05 m long core comprises a 7,000 year long Holocene record. The selected species were Orbulina universa, Globigerinoides ruber, Globigerinoides sacculifer, Globorotalia menardii and Globigerinella aequilateralis, which live in the upper 200 m of the water column. The Mg/Ca ratios of these different foraminifers show species-specific values, which represent a distinct habitat depth. With this species-specific Mg/Ca ratios we can reconstruct a temperature profile through the water column. The lowest Mg/Ca are shown by G. menardii (2.5 - 4 mmol/mol), followed by G. sacculifer (4.2 - 5.6 mmol/mol), G. ruber (5.1 - 7.2 mmol/mol) and G. aequilateralis (5.5 - 8.7 mmol/mol). Highest are shown by O. universa (6 - 14 mmol/mol). During the Little Ice Age, the Mg/Ca ratios of all species except for the deeper dwelling G. menardii, became more variable and showed lower ratios. The shallow dwelling species like G. ruber and G. sacculifer display an increase in the Mg/Ca ratios during the Medieval Warm Period. Our data show that transferring Mg/Ca ratios into SST based calibration curves known from literature needs re-evaluation. Species-specific calibration seems to be necessary to achieve reliable results.

  5. Vegetation and land carbon feedbacks in the high-resolution transient Holocene simulations using the MPI Earth system model

    Science.gov (United States)

    Brovkin, Victor; Lorenz, Stephan; Raddatz, Thomas

    2017-04-01

    Plants influence climate through changes in the land surface biophysics (albedo, transpiration) and concentrations of the atmospheric greenhouse gases. One of the interesting periods to investigate a climatic role of terrestrial biosphere is the Holocene, when, despite of the relatively steady global climate, the atmospheric CO2 grew by about 20 ppm from 7 kyr BP to pre-industrial. We use a new setup of the Max Planck Institute Earth System Model MPI-ESM1 consisting of the latest version of the atmospheric model ECHAM6, including the land surface model JSBACH3 with carbon cycle and vegetation dynamics, coupled to the ocean circulation model MPI-OM, which includes the HAMOCC model of ocean biogeochemistry. The model has been run for several simulations over the Holocene period of the last 8000 years under the forcing data sets of orbital insolation, atmospheric greenhouse gases, volcanic aerosols, solar irradiance and stratospheric ozone, as well as land-use changes. In response to this forcing, the land carbon storage increased by about 60 PgC between 8 and 4 kyr BP, stayed relatively constant until 2 kyr BP, and decreased by about 90 PgC by 1850 AD due to land use changes. Vegetation and soil carbon changes significantly affected atmospheric CO2 during the periods of strong volcanic eruptions. In response to the eruption-caused cooling, the land initially stores more carbon as respiration decreases, but then it releases even more carbon due to productivity decrease. This decadal- scale variability helps to quantify the vegetation and land carbon feedbacks during the past periods when the temporal resolution of the ice-core CO2 record is not sufficient to capture fast CO2 variations. From a set of Holocene simulations with prescribed or interactive atmospheric CO2, we get estimates of climate-carbon feedback useful for future climate studies. Members of the Hamburg Holocene Team: Jürgen Bader1, Sebastian Bathiany2, Victor Brovkin1, Martin Claussen1,3, Traute Cr

  6. Vegetation and Carbon Cycle Dynamics in the High-Resolution Transient Holocene Simulations Using the MPI Earth System Model

    Science.gov (United States)

    Brovkin, V.; Lorenz, S.; Raddatz, T.; Claussen, M.; Dallmeyer, A.

    2017-12-01

    -scale variability helps to quantify the vegetation and land carbon feedbacks during the past periods when the temporal resolution of the ice-core CO2 record is not sufficient to capture fast CO2 variations. From a set of Holocene simulations with prescribed or interactive atmospheric CO2, we get estimates of climate-carbon feedback useful for future climate studies.

  7. Intra- and interrater reliability of the Chicago Classification of achalasia subtypes in pediatric high-resolution esophageal manometry (HRM) recordings

    NARCIS (Netherlands)

    Singendonk, M. M. J.; Rosen, R.; Oors, J.; Rommel, N.; van Wijk, M. P.; Benninga, M. A.; Nurko, S.; Omari, T. I.

    2017-01-01

    BackgroundSubtyping achalasia by high-resolution manometry (HRM) is clinically relevant as response to therapy and prognosis have shown to vary accordingly. The aim of this study was to assess inter- and intrarater reliability of diagnosing achalasia and achalasia subtyping in children using the

  8. Comparison of infrared spectroscopy techniques: developing an efficient method for high resolution analysis of sediment properties from long records

    Science.gov (United States)

    Hahn, Annette; Rosén, Peter; Kliem, Pierre; Ohlendorf, Christian; Persson, Per; Zolitschka, Bernd; Pasado Science Team

    2010-05-01

    The analysis of sediment samples in visible to mid-infrared spectra is ideal for high-resolution records. It requires only small amounts (0.01-0.1g dry weight) of sample material and facilitates rapid and cost efficient analysis of a wide variety of biogeochemical properties on minerogenic and organic substances (Kellner et al. 1998). One of these techniques, the Diffuse Reflectance Fourier Transform Infrared Spectrometry (DRIFTS), has already been successfully applied to lake sediment from very different settings and has shown to be a promising technique for high resolution analyses of long sedimentary records on glacial-interglacial timescales (Rosén et al. 2009). However, the DRIFTS technique includes a time-consuming step where sediment samples are mixed with KBr. To assess if alternative and more rapid infrared (IR) techniques can be used, four different IR spectroscopy techniques are compared for core catcher sediment samples from Laguna Potrok Aike - an ICDP site located in southernmost South America. Partial least square (PLS) calibration models were developed using the DRIFTS technique. The correlation coefficients (R) for correlations between DRIFTS-inferred and conventionally measured biogeochemical properties show values of 0.80 for biogenic silica (BSi), 0.95 for total organic carbon (TOC), 0.91 for total nitrogen (TN), and 0.92 for total inorganic carbon (TIC). Good statistical performance was also obtained by using the Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy ATR-FTIRS technique which requires less sample preparation. Two devices were used, the full-sized Bruker Equinox 252 and the smaller and less expensive Bruker Alpha. R for ATR-FTIRS-inferred and conventionally measured biogeochemical properties were 0.87 (BSi), 0.93 (TOC), 0.90 (TN), and 0.91 (TIC) for the Alpha, and 0.78 (TOC), 0.85 (TN), 0.79 (TIC) for the Equinox 252 device. As the penetration depth of the IR beam is frequency dependent, a firm surface contact of

  9. A high-resolution Early Holocene-late MIS 3 environmental rock- and palaeomagnetic record from Lake Sf. Ana, Carpathian Mts, Romania

    Directory of Open Access Journals (Sweden)

    Daniel VERES

    2014-11-01

    Full Text Available Lacustrine sediments are excellent sources of palaeoenvironmental and palaeoclimatic information because they usually provide continuous and high-resolution records. In centraleastern Europe however lacustrine records that extend beyond the Holocene are rather sparse.Palaeomagnetic records from this region are also insufficiently explored, and usually associated with terrestrial deposits such as loess. In this context, the lacustrine record of Lake Sf. Ana, a volcanic crater lake in the East Carpathians, Romania, provides an important archive for reconstructing past paleomagnetic secular variation in the region from early Holocene to late Marine Isotope Stage (MIS 3.

  10. Visualization by high resolution immunoelectron microscopy of the transient receptor potential vanilloid-1 at inhibitory synapses of the mouse dentate gyrus.

    Directory of Open Access Journals (Sweden)

    Miren-Josune Canduela

    Full Text Available We have recently shown that the transient receptor potential vanilloid type 1 (TRPV1, a non-selective cation channel in the peripheral and central nervous system, is localized at postsynaptic sites of the excitatory perforant path synapses in the hippocampal dentate molecular layer (ML. In the present work, we have studied the distribution of TRPV1 at inhibitory synapses in the ML. With this aim, a preembedding immunogold method for high resolution electron microscopy was applied to mouse hippocampus. About 30% of the inhibitory synapses in the ML are TRPV1 immunopositive, which is mostly localized perisynaptically (∼60% of total immunoparticles at postsynaptic dendritic membranes receiving symmetric synapses in the inner 1/3 of the layer. This TRPV1 pattern distribution is not observed in the ML of TRPV1 knock-out mice. These findings extend the knowledge of the subcellular localization of TRPV1 to inhibitory synapses of the dentate molecular layer where the channel, in addition to excitatory synapses, is present.

  11. Transient regional climate change: analysis of the summer climate response in a high-resolution, century-scale, ensemble experiment over the continental United States

    Science.gov (United States)

    Diffenbaugh, Noah S.; Ashfaq, Moetasim; Scherer, Martin

    2013-01-01

    Integrating the potential for climate change impacts into policy and planning decisions requires quantification of the emergence of sub-regional climate changes that could occur in response to transient changes in global radiative forcing. Here we report results from a high-resolution, century-scale, ensemble simulation of climate in the United States, forced by atmospheric constituent concentrations from the Special Report on Emissions Scenarios (SRES) A1B scenario. We find that 21st century summer warming permanently emerges beyond the baseline decadal-scale variability prior to 2020 over most areas of the continental U.S. Permanent emergence beyond the baseline annual-scale variability shows much greater spatial heterogeneity, with emergence occurring prior to 2030 over areas of the southwestern U.S., but not prior to the end of the 21st century over much of the southcentral and southeastern U.S. The pattern of emergence of robust summer warming contrasts with the pattern of summer warming magnitude, which is greatest over the central U.S. and smallest over the western U.S. In addition to stronger warming, the central U.S. also exhibits stronger coupling of changes in surface air temperature, precipitation, and moisture and energy fluxes, along with changes in atmospheric circulation towards increased anticylonic anomalies in the mid-troposphere and a poleward shift in the mid-latitude jet aloft. However, as a fraction of the baseline variability, the transient warming over the central U.S. is smaller than the warming over the southwestern or northeastern U.S., delaying the emergence of the warming signal over the central U.S. Our comparisons with observations and the Coupled Model Intercomparison Project Phase 3 (CMIP3) ensemble of global climate model experiments suggest that near-term global warming is likely to cause robust sub-regional-scale warming over areas that exhibit relatively little baseline variability. In contrast, where there is greater

  12. High-resolution onshore-offshore morpho-bathymetric records of modern chalk and granitic shore platforms in NW France

    Science.gov (United States)

    Duperret, Anne; Raimbault, Céline; Le Gall, Bernard; Authemayou, Christine; van Vliet-Lanoë, Brigitte; Regard, Vincent; Dromelet, Elsa; Vandycke, Sara

    2016-07-01

    Modern shore platforms developed on rocky coasts are key areas for understanding coastal erosion processes during the Holocene. This contribution offers a detailed picture of two contrasted shore-platform systems, based on new high-resolution shallow-water bathymetry, further coupled with aerial LiDAR topography. Merged land-sea digital elevation models were achieved on two distinct types of rocky coasts along the eastern English Channel in France (Picardy and Upper-Normandy: PUN) and in a NE Atlantic area (SW Brittany: SWB) in NW France. About the PUN case, submarine steps, identified as paleo-shorelines, parallel the actual coastline. Coastal erosive processes appear to be continuous and regular through time, since mid-Holocene at least. In SWB, there is a discrepancy between contemporary coastline orientation and a continuous step extending from inland to offshore, identified as a paleo-shoreline. This illustrates a polyphased and inherited shore platform edification, mainly controlled by tectonic processes.

  13. High-resolution Atmospheric pCO2 Reconstruction across the Paleogene Using Marine and Terrestrial δ13C records

    Science.gov (United States)

    Cui, Y.; Schubert, B.

    2016-02-01

    The early Paleogene (63 to 47 Ma) is considered to have a greenhouse climate1 with proxies suggesting atmospheric CO2 levels (pCO2) approximately 2× pre-industrial levels. However, the proxy based pCO2 reconstructions are limited and do not allow for assessment of changes in pCO2 at million to sub-million year time scales. It has recently been recognized that changes in C3 land plant carbon isotope fractionation can be used as a proxy for pCO2 with quantifiable uncertainty2. Here, we present a high-resolution pCO2 reconstruction (n = 597) across the early Paleogene using published carbon isotope data from both terrestrial organic matter and marine carbonates. The minimum and maximum pCO2 values reconstructed using this method are broad (i.e., 170 +60/-40 ppmv to 2000 +4480/-1060 ppmv) and reflective of the wide range of environments sampled. However, the large number of measurements allows for a robust estimate of average pCO2 during this time interval ( 400 +260/-120 ppmv), and indicates brief (sub-million-year) excursions to very high pCO2 during hyperthermal events (e.g., the PETM). By binning our high-resolution pCO2 data at 1 million year intervals, we can compare our dataset to the other available pCO2 proxies. Our result is broadly consistent with pCO2 levels reconstructed using other proxies, with the exception of paleosol-based pCO2 estimates spanning 53 to 50 Ma. At this timescale, no proxy suggests pCO2 higher than 2000 ppmv, whereas the global surface ocean temperature is considered to be >10 oC warmer than today. Recent climate modeling suggests that low atmospheric pressure during this time period could help reconcile the apparent disconnect between pCO2 and temperature and contribute to the greenhouse climate3. References1. Huber, M., Caballero, R., 2011. Climate of the Past 7, 603-633. 2. Schubert, B.A., Jahren, A.H., 2015. Geology 43, 435-438. 3. Poulsen, C.J., Tabor, C., White, J.D., 2015. Science 348, 1238-1241.

  14. A New Alignment Method Based on The Wavelet Multi-Scale Cross-Correlation for Noisy High Resolution ECG Records

    National Research Council Canada - National Science Library

    Laciar, E

    2001-01-01

    ... between the wavelet transforms of the template and the detected beat, respectively. The wavelet and temporal methods were tested for several simulated records corrupted with white noise and electromyographic (EMG...

  15. Permanent recording of transient lattice perturbations

    International Nuclear Information System (INIS)

    Russell, F.M.

    1989-04-01

    A new solid-state recording mechanism has been identified which is capable of recording the tracks of charged light leptons and the tracks of uncharged supra-ballistic phonons. The dynamic range for recording charged leptons exceeds 50:1 with a minimum sensitivity of dE/dx ≅ 0.01 MeV/cm. For supra-ballistic phonons their energy must exceed ≅ 10eV to be recorded. The recording mechanism depends upon the presence in a crystal of muscovite of a low concentration of mobile impurity atoms which are normally energetically unable to accrete. The passage of a charged particle or of an energetic ballistic phonon locally modifies the crystal internal potentials to allow the impurity atoms to accrete, driven by their thermal energy, to form stable nucleation sites. Further accretion of the impurity at the nucleation sites causes massive decoration giving a lateral magnification of upto 10 5 and so rendering the tracks visible to the unaided eye. (Author)

  16. A high-resolution Holocene speleothem record from NE Romania: the nexus of Arctic and North Atlantic atmospheric circulations

    Science.gov (United States)

    Constantin, S.; Pourmand, A.; Moldovan, O.; Sharifi, A.; Mehterian, S.; Swart, P. K.

    2017-12-01

    The Romanian Carpathians act as a geomorphological barrier between different atmospheric circulation systems over Central and Eastern Europe; the NW of Romania lies under the remote influence of the North Atlantic oscillation, while the NE is influenced by the Arctic climate. In NW Romania, previous stable isotope studies of speleothems have not yielded a clear account of abrupt climate oscillations during the Holocene. Here we present results from a stalagmite collected from the Tauşoare Cave, located in NE Carpathians. The chronology of stalagmite T141 is based on 15 high-precision Th/U dates ranging between 32 and 1.1 ka with a continuous growth between 13.3 and 1.1 ka. The portion of the record within the Holocene was analyzed for δ18O and δ13C at a resolution ranging between 15 to 200 years/sample. The resulting δ18O record captures the Younger Dryas (YD) event centered at 12.9 ka, with δ18O values about 4 ‰ more depleted than those corresponding to the Holocene Climatic Optimum. The 8.2 ka event appears to be also captured in the record, although less prominent. The T141 isotope record is significantly different when compared to coeval records measured in speleothems from NW Carpathians, which do not exhibit marked changes during the YD or 8.2 ka events. This is likely due to the contrasting effect of temperature and atmospheric transport on δ18O signal in NW Romania. Within a distance of 200 km to the east, on the eastern flank of the Carpathian range, the δ18O signal of the Arctic circulation appears to be more prominent and clearly exhibits a positive relationship with temperature changes.

  17. Large-scale, high-resolution multielectrode-array recording depicts functional network differences of cortical and hippocampal cultures.

    Directory of Open Access Journals (Sweden)

    Shinya Ito

    Full Text Available Understanding the detailed circuitry of functioning neuronal networks is one of the major goals of neuroscience. Recent improvements in neuronal recording techniques have made it possible to record the spiking activity from hundreds of neurons simultaneously with sub-millisecond temporal resolution. Here we used a 512-channel multielectrode array system to record the activity from hundreds of neurons in organotypic cultures of cortico-hippocampal brain slices from mice. To probe the network structure, we employed a wavelet transform of the cross-correlogram to categorize the functional connectivity in different frequency ranges. With this method we directly compare, for the first time, in any preparation, the neuronal network structures of cortex and hippocampus, on the scale of hundreds of neurons, with sub-millisecond time resolution. Among the three frequency ranges that we investigated, the lower two frequency ranges (gamma (30-80 Hz and beta (12-30 Hz range showed similar network structure between cortex and hippocampus, but there were many significant differences between these structures in the high frequency range (100-1000 Hz. The high frequency networks in cortex showed short tailed degree-distributions, shorter decay length of connectivity density, smaller clustering coefficients, and positive assortativity. Our results suggest that our method can characterize frequency dependent differences of network architecture from different brain regions. Crucially, because these differences between brain regions require millisecond temporal scales to be observed and characterized, these results underscore the importance of high temporal resolution recordings for the understanding of functional networks in neuronal systems.

  18. Surface water processes in the Indonesian throughflow as documented by a high-resolution coral Δ14C record

    Science.gov (United States)

    Fallon, Stewart J.; Guilderson, Thomas P.

    2008-09-01

    To explore the seasonal to decadal variability in surface water masses that contribute to the Indonesian throughflow, we have generated a 115-year bimonthly coral-based radiocarbon time series from a coral in the Makassar Straits. In the pre-bomb (pre-1955) era from 1890 to 1954, the radiocarbon time series occasionally displays a small seasonal signal (10-15‰). After 1954 the radiocarbon record increases rapidly, in response to the increased atmospheric 14C content caused by nuclear weapons testing. From 1957 to 1986 the record displays clear seasonal variability from 15 to 60‰ and the post-bomb peak (163 per mil) occurred in 1974. The seasonal cycle of radiocarbon can be attributed to variations of surface waters passing through the South Makassar Strait. Southern Makassar is under the influence of the Northwest Monsoon, which is responsible for the high austral summer radiocarbon (North Pacific waters) and the Southeast Monsoon that flushes back a mixture of low (South Pacific and upwelling altered) radiocarbon water from the Banda Sea. The coral record also shows a significant 14C peak in 1955 due to the bomb-14C water advected into this region from nuclear weapons tests in the Marshall Islands in 1954.

  19. Recording Approach of Heritage Sites Based on Merging Point Clouds from High Resolution Photogrammetry and Terrestrial Laser Scanning

    Science.gov (United States)

    Grussenmeyer, P.; Alby, E.; Landes, T.; Koehl, M.; Guillemin, S.; Hullo, J. F.; Assali, P.; Smigiel, E.

    2012-07-01

    Different approaches and tools are required in Cultural Heritage Documentation to deal with the complexity of monuments and sites. The documentation process has strongly changed in the last few years, always driven by technology. Accurate documentation is closely relied to advances of technology (imaging sensors, high speed scanning, automation in recording and processing data) for the purposes of conservation works, management, appraisal, assessment of the structural condition, archiving, publication and research (Patias et al., 2008). We want to focus in this paper on the recording aspects of cultural heritage documentation, especially the generation of geometric and photorealistic 3D models for accurate reconstruction and visualization purposes. The selected approaches are based on the combination of photogrammetric dense matching and Terrestrial Laser Scanning (TLS) techniques. Both techniques have pros and cons and recent advances have changed the way of the recording approach. The choice of the best workflow relies on the site configuration, the performances of the sensors, and criteria as geometry, accuracy, resolution, georeferencing, texture, and of course processing time. TLS techniques (time of flight or phase shift systems) are widely used for recording large and complex objects and sites. Point cloud generation from images by dense stereo or multi-view matching can be used as an alternative or as a complementary method to TLS. Compared to TLS, the photogrammetric solution is a low cost one, as the acquisition system is limited to a high-performance digital camera and a few accessories only. Indeed, the stereo or multi-view matching process offers a cheap, flexible and accurate solution to get 3D point clouds. Moreover, the captured images might also be used for models texturing. Several software packages are available, whether web-based, open source or commercial. The main advantage of this photogrammetric or computer vision based technology is to get

  20. Two high resolution terrestrial records of atmospheric Pb deposition from New Brunswick, Canada, and Loch Laxford, Scotland

    International Nuclear Information System (INIS)

    Kylander, Malin E.; Weiss, Domink J.; Kober, Bernd

    2009-01-01

    Environmental archives like peat deposits allow for the reconstruction of both naturally and anthropogenically forced changes in the biogeochemical cycle of Pb as well as the quantification of past and present atmospheric Pb pollution. However, records of atmospheric Pb deposition from pre-industrial times are lacking. In a publication by Weiss et al. [Weiss, D., Shotyk, W., Boyle, E.A., Kramers, J.D., Appleby, P.G., Cheburkin, A.K., Comparative study of the temporal evolution of atmospheric lead deposition in Scotland and eastern Canada using blanket peat bogs. Sci Total Environ 2002;292:7-18]. Pb isotopes data measured by Q-ICP-MS and TIMS, concentration and enrichment data was presented for sites in eastern Canada (PeW1) and northwestern Scotland (LL7c), dating to 1586 A.D and 715 A.D., respectively. Here these same cores are re-analysed for Pb isotopes by MC-ICP-MS thereby acquiring 204 Pb data and improving on the original data in terms of resolution and temporal coverage. Significant differences were found between the Q-ICP-MS/TIMS and MC-ICP-MS measurements, particularly at PeW1. These discrepancies are attributed to the problematic presence of organic matter during sample preparation and analysis complicated by the heterogeneity of the organic compounds that survived sample preparation steps. The precision and accuracy of Pb isotopes in complex matrices like peat is not always well estimated by industrial standards like NIST-SRM 981 Pb. Lead pollution histories at each site were constructed using the MC-ICP-MS data. The entire LL7c record is likely subject to anthropogenic additions. Contributions from local mining were detected in Medieval times. Later, coal use and mining in Scotland, Wales and England became important. After industrialization (ca. 1885 A.D.) contributions from Broken Hill type ores and hence, leaded petrol, dominate atmospheric Pb signatures right up to modern times. At PeW1 anthropogenic impacts are first distinguishable in the late 17

  1. High-resolution records detect human-caused changes to the boreal forest wildfire regime in interior Alaska

    Science.gov (United States)

    Gaglioti, Benjamin V.; Mann, Daniel H.; Jones, Benjamin M.; Wooller, Matthew J.; Finney, Bruce P.

    2016-01-01

    Stand-replacing wildfires are a keystone disturbance in the boreal forest, and they are becoming more common as the climate warms. Paleo-fire archives from the wildland–urban interface can quantify the prehistoric fire regime and assess how both human land-use and climate change impact ecosystem dynamics. Here, we use a combination of a sedimentary charcoal record preserved in varved lake sediments (annually layered) and fire scars in living trees to document changes in local fire return intervals (FRIs) and regional fire activity over the last 500 years. Ace Lake is within the boreal forest, located near the town of Fairbanks in interior Alaska, which was settled by gold miners in AD 1902. In the 400 years before settlement, fires occurred near the lake on average every 58 years. After settlement, fires became much more frequent (average every 18  years), and background charcoal flux rates rose to four times their preindustrial levels, indicating a region-wide increase in burning. Despite this surge in burning, the preindustrial boreal forest ecosystem and permafrost in the watershed have remained intact. Although fire suppression has reduced charcoal influx since the 1950s, an aging fuel load experiencing increasingly warm summers may pose management problems for this and other boreal sites that have similar land-use and fire histories. The large human-caused fire events that we identify can be used to test how increasingly common megafires may alter ecosystem dynamics in the future.

  2. High-resolution recording of particle tracks with in-line holography in a large cryogenic bubble chamber

    CERN Document Server

    Harigel, G G

    2000-01-01

    Holography has been used successfully in combination with conventional optics for the first time in a large cryogenic bubble chamber, the 15-Foot Bubble Chamber at the Fermi National Accelerator Laboratory (FNAL), during a physics run in a high-energy neutrino beam. The innovative system combined the reference beam with the object beam, irradiating a conical volume of ~1.5 m/sup 3/. Bubble tracks from neutrino interactions with a width of ~120 mu m have been recorded with good contrast. The ratio of intensities of the object light to the reference light striking the film is called the beam branching ratio (BBR). We obtained in our experiment an exceedingly small minimum-observable ratio of BBR=(0.54/0.21)*10/sup -7/. The technology has the potential for a wide range of applications. This paper describes the various difficulties in achieving the success. It required the development of laser pulse stretching via enhanced closed loop control with slow Q-switching, to overcome excessive heating of the cryogenic l...

  3. High-resolution δ13C record of fossil wood and bulk organic matter from a deep Oligocene lacustrine succession, Bach Long Vi Island, Vietnam

    Science.gov (United States)

    Rizzi, M.; Schovsbo, N. H.; Fyhn, M. B. W.; Korte, C.

    2017-12-01

    We present a high-resolution stable isotope record based on bulk organic matter (δ13Corg) and fossil wood (δ13Cwood) originating from Oligocene deep lacustrine sediments cored on the Bach Long Vi Island, northern Gulf of Tonkin, offshore Vietnam. The sediments are exceptionally well preserved. They are thus excellently suited for a detailed stratigraphical analysis of the stable isotope record and as proxy for environmental and climatic changes within this period. The sediments were deposited in rapid subsiding, narrow and elongated fault-bound graben (Fyhn and Phach, 2015) and are represented by deep pelagic lacustrine organic-rich mud interrupted by numerous density-flow deposits (Hovikoski et al., 2016). The density-flow deposits contain abundant fragments of fossil wood. Therefore it was possible to obtain 262 coalified wood fragments together with 1063 bulk organic samples throughout the span of the core. This allowed to establish a high resolution stable C isotope record (δ13Corg and δ13Cwood). In addition 2464 handheld XRF determinations were carried out to further characterize the depositional environment (Rizzi et al., 2017). The organic carbon isotope trend from the 500 m core succession provides insight into the palaeoenvironmental changes of the lake during the Oligocene. Both, global and local factors control the δ13C variations. The aim of the study is to obtain pure global δ13Corg and δ13Cwood signals that would allow comparison of the studied sediments with coeval syn-rift successions in the South China Sea region and other parts of the world. [1] Fyhn and Phach (2015) Tectonics, 34(2): 290-312. [2] Hovikoski et al. (2016) Journal of Sedimentary Research, 86(8): 982-1007. [3] Rizzi et al. (2017) EGU General Assembly Abstract EGU 2017-17584.

  4. Regional influence of decadal to multidecadal Atlantic Oscillations during the last two millennia in Morocco, inferred from two high resolution δ18O speleothem records

    Science.gov (United States)

    Ait Brahim, Yassine; Sifeddine, Abdelfettah; Khodri, Myriam; Bouchaou, Lhoussaine; Cruz, Francisco W.; Pérez-Zanón, Núria; Wassenburg, Jasper A.; Cheng, Hai

    2017-04-01

    Climate projections predict substantial increase of extreme heats and drought occurrences during the coming decades in Morocco. It is however not clear what can be attributed to natural climate variability and to anthropogenic forcing, as hydroclimate variations observed in areas such as Morocco are highly influenced by the Atlantic climate modes. Since observational data sets are too short to resolve properly natural modes of variability acting on decadal to multidecadal timescales, high resolution paleoclimate reconstructions are the only alternative to reconstruct climate variability in the remote past. Herein, we present two high resolution and well dated speleothems oxygen isotope (δ18O) records sampled from Chaara and Ifoulki caves (located in Northeastern and Southwestern Morocco respectively) to investigate hydroclimate variations during the last 2000 years. Our results are supported by a monitoring network of δ18O in precipitation from 17 stations in Morocco. The new paleoclimate records are discussed in the light of existing continental and marine paleoclimate proxies in Morocco to identify significant correlations at various lead times with the main reconstructed oceanic and atmospheric variability modes and possible climate teleconnections that have potentially influenced the climate during the last two millennia in Morocco. The results reveal substantial decadal to multidecadal swings between dry and humid periods, consistent with regional paleorecords. Evidence of dry conditions exist during the Medieval Climate Anomaly (MCA) period and the Climate Warm Period (CWP) and humid conditions during the Little Ice Age (LIA) period. Statistical analyses suggest that the climate of southwestern Morocco remained under the combined influence of both the Atlantic Multidecadal Oscillation (AMO) and the North Atlantic Oscillation (NAO) over the last two millennia. Interestingly, the generally warmer MCA and colder LIA at longer multidecadal timescales probably

  5. A high-resolution record of Holocene millennial-scale oscillations of surface water, foraminiferal paleoecology and sediment redox chemistry in the SE Brazilian margin

    Science.gov (United States)

    Dias, B. B.; Barbosa, C. F.; Albuquerque, A. L.; Piotrowski, A. M.

    2014-12-01

    Holocene millennial-scale oscillations and Bond Events (Bond et al. 1997) are well reported in the North Atlantic as consequence of fresh water input and weaking of the Atlantic Meridional Overturning Circulation (AMOC). It has been hypothesized that the effect of weaking of AMOC would lead to warming in the South Atlantic due to "heat piracy", causing surface waters to warm and a reorganization of surface circulation. There are few reconstructions of AMOC strength in the South Atlantic, and none with a high resolution Holocene record of changes of productivity and the biological pump. We reconstruct past changes in the surface water mass hydrography, productivity, and sediment redox changes in high-resolution in the core KCF10-01B, located 128 mbsl water depth off Cabo Frio, Brazil, a location where upwelling is strongly linked to surface ocean hydrography. We use Benthic Foraminiferal Accumulation Rate (BFAR) to reconstruct productivity, which reveals a 1.3kyr cyclicity during the mid- and late-Holocene. The geochemistry of trace and rare earth elements on foraminiferal Fe-Mn oxide coatings show changes in redox-sensitive elements indicating that during periods of high productivity there were more reducing conditions in sediment porewaters, producing a Ce anomaly and reduction and re-precipitation of Mn oxides. Bond events 1-7 were identified by a productivity increase along with reducing sediment conditions which was likely caused by Brazil Current displacement offshore allowing upwelling of the nutritive bottom water South Atlantic Central Waters (SACW) to the euphotic zone and a stronger local biological pump. In a global context, correlation with other records show that this occurred during weakened AMOC and southward displacement of the ITCZ. We conclude that Bond climatic events and millennial-scale variability of AMOC caused sea surface hydrographic changes off the Brazilian Margin leading to biological and geochemical changes recorded in coastal records

  6. Northern Hemisphere Influence on the Position of the SPCZ During MIS3: a High Resolution Glacial Rainfall Record from a Niuean Speleothem

    Science.gov (United States)

    Sinclair, D.; Sherrell, R. M.; Tremaine, D. M.; Sweeney, J. R.; Rowe, H.; Wright, J. D.; Mortlock, R. A.; Hellstrom, J. C.; Cheng, H.; Min, A.; Edwards, R. L.

    2017-12-01

    Here we present a high-resolution glacial paleorainfall record from the heart of the South Pacific Convergence Zone (SPCZ) extracted from a stalagmite from the remote island of Niue (19°03'S 169°52'W). The record spans much of MIS3 (25-45 ka) and captures rapid rainfall changes associated with shifts in the SPCZ. It is clear that rapid climate shifts in the Northern Hemisphere have a strong influence on the SPCZ. All of the warm Dansgaard-Oeschger (`D-O') interstadials across this period are represented by rainfall increases, with D-O Events 9-11 particularly strongly represented. Since Niue lies south of the core of the SPCZ, this implies that rather than shifting northwards (as the ITCZ does), the SPCZ instead rotates clockwise in response to northern Hemisphere warming (analogous to a shift between modern El Nino and La Nina states). We propose that changes to surface ocean temperature gradients in the Eastern Pacific modulate the strength of the Wind Evaporation SST feedback, changing the size and westward penetration of the eastern Pacific dry zone, resulting in changes to the diagonality of the SPCZ. Our record also captures a response to strong northern Hemisphere cooling. The 25-45 ka record is bounded by large hiatuses (inferred dry conditions) coincident with cold Heinrich Stadials (HS) 2 and 5, while HS3 and HS4 are captured as distinct reductions in speleothem growth rate and proxy evidence for declining rainfall. This is consistent with a counter-clockwise rotation of the SPCZ during Northern cooling, supporting our proposed mechanism. Interestingly, our record also captures several other (non-Heinrich) cooling events, including a strong 500-year dry interval at 26ka that is seen in Chinese and Brazilian speleothems and coincides with a strong cooling over Asia (inferred from Greenland dust records). We note the (possibly coincidental) timing between this event and the Oruanui super-eruption at 25.6 ka.

  7. A 10,000 yr record of high-resolution Paleosecular Variation from a flowstone of Rio Martino Cave, Northwestern Alps, Italy

    Science.gov (United States)

    Zanella, Elena; Tema, Evdokia; Lanci, Luca; Regattieri, Eleonora; Isola, Ilaria; Hellstrom, John C.; Costa, Emanuele; Zanchetta, Giovanni; Drysdale, Russell N.; Magrì, Federico

    2018-03-01

    Speleothems are potentially excellent archives of the Earth's magnetic field, capable of recording its past variations. Their characteristics, such as the continuity of the record, the possibility to be easily dated, the almost instantaneous remanence acquisition and the high time-resolution make them potentially unique high-quality Paleosecular Variation (PSV) recorders. Nevertheless, speleothems are commonly characterized by low magnetic intensities, which often limits their resolution. Here we present a paleomagnetic study performed on two cores from a flowstone from the Rio Martino Cave (Western Alps, Italy). U/Th dating indicates that the flowstone's deposition covers almost the entire Holocene, spanning the period ca. 0.5-9.0 ka, while an estimation of its mean growth rate is around 1 mm per 15 years. The flowstone is composed of columnar calcite, characterized by a highly magnetic detrital content from meta-ophiolites in the cave's catchment. This favorable geological context results in an intense magnetic signal that permits the preparation and measurement of thin (∼3 mm depth equivalent) samples, each representing around 45 yr. The Characteristic Remanent Magnetization (ChRM), isolated after systematic stepwise Alternating Field demagnetization, is well defined, with Maximum Angular Deviation (MAD) generally lower than 10°. Paleomagnetic directional data allow the reconstruction of the PSV path during the Holocene for the area. Comparison of the new data with archeomagnetic data from Italian archeological and volcanic records and using the predictions of the SHA.DIF.14k and pfm9k.1a global geomagnetic field models shows that the Rio Martino flowstone represents an excellent recorder of the Earth's magnetic field during the last 9,000 years. Our high resolution paleomagnetic record, anchored by a high-quality chronology, provides promising data both for the detection of short term geomagnetic field variations and for complementing existing regional PSV

  8. Vital Recorder-a free research tool for automatic recording of high-resolution time-synchronised physiological data from multiple anaesthesia devices.

    Science.gov (United States)

    Lee, Hyung-Chul; Jung, Chul-Woo

    2018-01-24

    The current anaesthesia information management system (AIMS) has limited capability for the acquisition of high-quality vital signs data. We have developed a Vital Recorder program to overcome the disadvantages of AIMS and to support research. Physiological data of surgical patients were collected from 10 operating rooms using the Vital Recorder. The basic equipment used were a patient monitor, the anaesthesia machine, and the bispectral index (BIS) monitor. Infusion pumps, cardiac output monitors, regional oximeter, and rapid infusion device were added as required. The automatic recording option was used exclusively and the status of recording was frequently checked through web monitoring. Automatic recording was successful in 98.5% (4,272/4,335) cases during eight months of operation. The total recorded time was 13,489 h (3.2 ± 1.9 h/case). The Vital Recorder's automatic recording and remote monitoring capabilities enabled us to record physiological big data with minimal effort. The Vital Recorder also provided time-synchronised data captured from a variety of devices to facilitate an integrated analysis of vital signs data. The free distribution of the Vital Recorder is expected to improve data access for researchers attempting physiological data studies and to eliminate inequalities in research opportunities due to differences in data collection capabilities.

  9. UV-laser microdissection system - A novel approach for the preparation of high-resolution stable isotope records (δ13C/δ18O) from tree rings

    Science.gov (United States)

    Schollaen, Karina; Helle, Gerhard

    2013-04-01

    Intra-annual stable isotope (δ13C and δ18O) studies of tree rings at various incremental resolutions have been attempting to extract valuable seasonal climatic and environmental information or assessing plant ecophysiological processes. For preparing high-resolution isotope samples normally wood segments or cores are mechanically divided in radial direction or cut in tangential direction. After mechanical dissection, wood samples are ground to a fine powder and either cellulose is extracted or bulk wood samples are analyzed. Here, we present a novel approach for the preparation of high-resolution stable isotope records from tree rings using an UV-laser microdissection system. Firstly, tree-ring cellulose is directly extracted from wholewood cross-sections largely leaving the wood anatomical structure intact and saving time as compared to the classical procedure. Secondly, micro-samples from cellulose cross-sections are dissected with an UV-Laser dissection microscope. Tissues of interest from cellulose cross-sections are identified and marked precisely with a screen-pen and dissected via an UV-laser beam. Dissected cellulose segments were automatically collected in capsules and are prepared for stable isotope (δ13C and δ18O) analysis. The new techniques facilitate inter- and intra-annual isotope analysis on tree-ring and open various possibilities for comparisons with wood anatomy in plant eco-physiological studies. We describe the design and the handling of this novel methodology and discuss advantages and constraints given by the example of intra-annual oxygen isotope analysis on tropical trees.

  10. Normalizing XRF-scanner data: A cautionary note on the interpretation of high-resolution records from organic-rich lakes

    Science.gov (United States)

    Löwemark, L.; Chen, H.-F.; Yang, T.-N.; Kylander, M.; Yu, E.-F.; Hsu, Y.-W.; Lee, T.-Q.; Song, S.-R.; Jarvis, S.

    2011-04-01

    X-ray fluorescence (XRF) scanning of unlithified, untreated sediment cores is becoming an increasingly common method used to obtain paleoproxy data from lake records. XRF-scanning is fast and delivers high-resolution records of relative variations in the elemental composition of the sediment. However, lake sediments display extreme variations in their organic matter content, which can vary from just a few percent to well over 50%. As XRF scanners are largely insensitive to organic material in the sediment, increasing levels of organic material effectively dilute those components that can be measured, such as the lithogenic material (the closed-sum effect). Consequently, in sediments with large variations in organic material, the measured variations in an element will to a large extent mirror the changes in organic material. It is therefore necessary to normalize the elements in the lithogenic component of the sediment against a conservative element to allow changes in the input of the elements to be addressed. In this study we show that Al, which is the lightest element that can be measured using the Itrax XRF-scanner, can be used to effectively normalize the elements of the lithogenic fraction of the sediment against variations in organic content. We also show that care must be taken when choosing resolution and exposure time to ensure optimal output from the measurements.

  11. One gigasample per second transient recorder: a performance demonstration

    International Nuclear Information System (INIS)

    Linnenbrink, T.E.; Gradl, D.A.; Ritt, D.M.; DeWitte, G.J.; Hutton, J.D.

    1982-01-01

    The performance demonstrated by a one gigasample per second (1 Gs/s) transient recorder currently in advanced development portends an important new instrument for recording single transient data. A Charge-Coupled Device (CCD) is used to sample a continuous analog signal. Samples acquired at the full sampling rate (1 Gs/s) are temporarily stored in the CCD, then read out at a slow rate (e.g., 250 Ks/s) into a conventional analog-to-digital converter prior to storage in nonvolatile, digital memory. Enhanced circuitry and techniques developed over the past three years have yielded higher performance than originally anticipated. Accordingly, the target specification has been revised to reflect higher expectations

  12. A high-resolution record of the Matuyama-Brunhes transition from the Mediterranean region: The Valle di Manche section (Calabria, Southern Italy)

    Science.gov (United States)

    Macrì, Patrizia; Capraro, Luca; Ferretti, Patrizia; Scarponi, Daniele

    2018-05-01

    High-resolution palaeomagnetic and rock magnetic investigations on the Valle di Manche section (Crotone Basin, Calabria, Southern Italy) provide a detailed record of the Matuyama-Brunhes (M-B) reversal that, to our best knowledge, is the only available record of the last geomagnetic reversal for the Mediterranean on-land marine stratigraphy. The M-B transition can be pinpointed precisely, as it develops within a 3-cm-thick interval located just above a prominent tephra layer (the "Pitagora ash") where the sedimentation rates are about 27 cm/kyr. Demagnetization analyses indicate a stable palaeomagnetic behaviour throughout the section for both normal and reversed polarity directions, with demagnetization vectors aligned toward the origin of Zijderveld diagrams after the removal of a small viscous low-coercivity remanence component. In the lower part of the studied interval, some samples acquired a spurious gyromagnetic remanent magnetization (GRM) during AF demagnetization in high fields. Rock magnetic analyses confirm that magnetite is the main magnetic carrier for all measured specimens, which also have an abundant paramagnetic fraction. Only the lower part of the record, well below the M-B boundary, is characterized by a downward-increasing presence of iron sulphides (greigite). According to our chronology, which is based on a robust, cross-validated age model, the final reverse-to-normal directional change of the M-B transition occurred at ca. 786.9 ± 5 ka (error includes uncertainty in orbital tuning) and was very rapid, of the order of 100 years or less.

  13. High-resolution record of the Matuyama–Brunhes transition constrains the age of Javanese Homo erectus in the Sangiran dome, Indonesia

    Science.gov (United States)

    Hyodo, Masayuki; Matsu'ura, Shuji; Kamishima, Yuko; Kondo, Megumi; Takeshita, Yoshihiro; Kitaba, Ikuko; Danhara, Tohru; Aziz, Fachroel; Kurniawan, Iwan; Kumai, Hisao

    2011-01-01

    A detailed paleomagnetic study conducted in the Sangiran area, Java, has provided a reliable age constraint on hominid fossil-bearing formations. A reverse-to-normal polarity transition marks a 7-m thick section across the Upper Tuff in the Bapang Formation. The transition has three short reversal episodes and is overlain by a thick normal polarity magnetozone that was fission-track dated to the Brunhes chron. This pattern closely resembles another high-resolution Matuyama–Brunhes (MB) transition record in an Osaka Bay marine core. In the Sangiran sediments, four successive transitional polarity fields lie just below the presumed main MB boundary. Their virtual geomagnetic poles cluster in the western South Pacific, partly overlapping the transitional virtual geomagnetic poles from Hawaiian and Canary Islands’ lavas, which have a mean 40Ar/39Ar age of 776 ± 2 ka. Thus, the polarity transition is unambiguously the MB boundary. A revised correlation of tuff layers in the Bapang Formation reveals that the hominid last occurrence and the tektite level in the Sangiran area are nearly coincident, just below the Upper Middle Tuff, which underlies the MB transition. The stratigraphic relationship of the tektite level to the MB transition in the Sangiran area is consistent with deep-sea core data that show that the meteorite impact preceded the MB reversal by about 12 ka. The MB boundary currently defines the uppermost horizon yielding Homo erectus fossils in the Sangiran area. PMID:22106291

  14. High-resolution record of the Matuyama-Brunhes transition constrains the age of Javanese Homo erectus in the Sangiran dome, Indonesia.

    Science.gov (United States)

    Hyodo, Masayuki; Matsu'ura, Shuji; Kamishima, Yuko; Kondo, Megumi; Takeshita, Yoshihiro; Kitaba, Ikuko; Danhara, Tohru; Aziz, Fachroel; Kurniawan, Iwan; Kumai, Hisao

    2011-12-06

    A detailed paleomagnetic study conducted in the Sangiran area, Java, has provided a reliable age constraint on hominid fossil-bearing formations. A reverse-to-normal polarity transition marks a 7-m thick section across the Upper Tuff in the Bapang Formation. The transition has three short reversal episodes and is overlain by a thick normal polarity magnetozone that was fission-track dated to the Brunhes chron. This pattern closely resembles another high-resolution Matuyama-Brunhes (MB) transition record in an Osaka Bay marine core. In the Sangiran sediments, four successive transitional polarity fields lie just below the presumed main MB boundary. Their virtual geomagnetic poles cluster in the western South Pacific, partly overlapping the transitional virtual geomagnetic poles from Hawaiian and Canary Islands' lavas, which have a mean (40)Ar/(39)Ar age of 776 ± 2 ka. Thus, the polarity transition is unambiguously the MB boundary. A revised correlation of tuff layers in the Bapang Formation reveals that the hominid last occurrence and the tektite level in the Sangiran area are nearly coincident, just below the Upper Middle Tuff, which underlies the MB transition. The stratigraphic relationship of the tektite level to the MB transition in the Sangiran area is consistent with deep-sea core data that show that the meteorite impact preceded the MB reversal by about 12 ka. The MB boundary currently defines the uppermost horizon yielding Homo erectus fossils in the Sangiran area.

  15. First High-Resolution Record of Late Quaternary Environmental Changes in the Amundsen Sea, West Antarctica, Revealed by Multi-proxy Analysis of Drift Sediments

    Science.gov (United States)

    Horrocks, J.; Ó Cofaigh, C.; Lloyd, J. M.; Hillenbrand, C. D.; Kuhn, G.; Smith, J.; Ehrmann, W. U.; Esper, O.

    2015-12-01

    The Amundsen Sea sector of the West Antarctic Ice Sheet (WAIS) is experiencing rapid mass loss and there is a pressing need to place the contemporary ice-sheet changes into a longer term context. The continental rise in this region is characterised by large sediment mounds that are shaped by westward flowing bottom currents and that resemble contouritic drifts existing offshore from the Antarctic Peninsula. Similar to the Antarctic Peninsula drifts, marine sediment cores from the poorly studied sediment mounds in the Amundsen Sea have the potential to provide reliable records of dynamical ice-sheet behaviour in West Antarctica and palaeoceanographic changes in the Southern Ocean during the Late Quaternary that can be reconstructed from their terrestrial, biogenic and authigenic components. Here we use multi-proxy data from three sediment cores recovered from two of the Amundsen Sea mounds to present the first high-resolution study of environmental changes on this part of the West Antarctic continental margin over the glacial-interglacial cycles of the Late Quaternary. Age constraints for the records are derived from biostratigraphy, AMS 14C dates and lithostratigraphy. We focus on the investigation of processes for drift formation, thereby using grain size and sortable silt data to reconstruct changes in bottom current speed and to identify episodes of current winnowing. Data on geochemical and mineralogical sediment composition and physical properties are used to infer both changes in terrigenous sediment supply in response to the advance and retreat of the WAIS across the Amundsen Sea shelf and changes in biological productivity that are mainly controlled by the duration of annual sea-ice coverage. We compare our data sets from the Amundsen Sea mounds to those from the well-studied Antarctic Peninsula drifts, thereby highlighting similarities and discrepancies in depositional processes and climatically-driven environmental changes.

  16. Ultra-high resolution pollen record from the northern Andes reveals rapid shifts in montane climates within the last two glacial cycles

    Directory of Open Access Journals (Sweden)

    M. H. M. Groot

    2011-03-01

    Full Text Available Here we developed a composite pollen-based record of altitudinal vegetation changes from Lake Fúquene (5° N in Colombia at 2540 m elevation. We quantitatively calibrated Arboreal Pollen percentages (AP% into mean annual temperature (MAT changes with an unprecedented ~60-year resolution over the past 284 000 years. An age model for the AP% record was constructed using frequency analysis in the depth domain and tuning of the distinct obliquity-related variations to the latest marine oxygen isotope stacked record. The reconstructed MAT record largely concurs with the ~100 and 41-kyr (obliquity paced glacial cycles and is superimposed by extreme changes of up to 7 to 10° Celsius within a few hundred years at the major glacial terminations and during marine isotope stage 3, suggesting an unprecedented North Atlantic – equatorial link. Using intermediate complexity transient climate modelling experiments, we demonstrate that ice volume and greenhouse gasses are the major forcing agents causing the orbital-related MAT changes, while direct precession-induced insolation changes had no significant impact on the high mountain vegetation during the last two glacial cycles.

  17. High Resolution Elevation Contours

    Data.gov (United States)

    Minnesota Department of Natural Resources — This dataset contains contours generated from high resolution data sources such as LiDAR. Generally speaking this data is 2 foot or less contour interval.

  18. NOAA Climate Data Record (CDR) of Intersatellite Calibrated Clear-Sky High Resolution Infrared Radiation Sounder (HIRS) Channel 12 Brightness Temperature Version 3

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The High-Resolution Infrared Radiation Sounder (HIRS) of intersatellite calibrated channel 12 brightness temperature (TB) product is a gridded global monthly time...

  19. Multiple oscillations during the Lateglacial as recorded in a multi-proxy, high-resolution record of the Moervaart palaeolake (NW Belgium)

    Science.gov (United States)

    Bos, Johanna A. A.; De Smedt, Philippe; Demiddele, Hendrik; Hoek, Wim Z.; Langohr, Roger; Marcelino, Vera; Van Asch, Nelleke; Van Damme, Dirk; Van der Meeren, Thijs; Verniers, Jacques; Boeckx, Pascal; Boudin, Mathieu; Court-Picon, Mona; Finke, Peter; Gelorini, Vanessa; Gobert, Stefan; Heiri, Oliver; Martens, Koen; Mostaert, Frank; Serbruyns, Lynn; Van Strydonck, Mark; Crombé, Philippe

    2017-04-01

    This paper presents the results of multi-disciplinary research carried out on the deposits of Moervaart depression, NW Belgium, one of the largest palaeolakes (∼25 km2) that existed during the Lateglacial interstadial in NW Europe. The multi-proxy study, including physical (organic matter and calcium carbonate, magnetic susceptibility, micromorphological), botanical (pollen, macrofossils, diatoms), zoological (ostracods, molluscs, chironomids) and chemical analyses (stable carbon and oxygen isotopes) has resulted in a detailed reconstruction of the Lateglacial landscape as well of the local conditions that prevailed in the lake itself. A chronology of the record was provided by radiocarbon dating and comparison with radiocarbon dates of the nearby Rieme site. These yielded a good match with the regional biostratigraphy. During the Lateglacial, vegetation and geomorphology of the landscape in general changed from a tundra landscape to a boreal forest. The vegetation development, however, was interrupted by a number of cold reversals. Three centennial-scale cold oscillations are present in the record: 1) the so-called Older Dryas corresponding to GI-1d in the Greenland ice-cores, 2) a short and pronounced cold event during the early Allerød, which could be correlated to GI-1c2 and 3) a cooling event during the late Allerød probably corresponding to the Intra Allerød Cold Period (IACP) or GI-1b. The latter most likely was responsible for the disappearance of the Moervaart palaeolake.

  20. High resolution solar observations

    International Nuclear Information System (INIS)

    Title, A.

    1985-01-01

    Currently there is a world-wide effort to develop optical technology required for large diffraction limited telescopes that must operate with high optical fluxes. These developments can be used to significantly improve high resolution solar telescopes both on the ground and in space. When looking at the problem of high resolution observations it is essential to keep in mind that a diffraction limited telescope is an interferometer. Even a 30 cm aperture telescope, which is small for high resolution observations, is a big interferometer. Meter class and above diffraction limited telescopes can be expected to be very unforgiving of inattention to details. Unfortunately, even when an earth based telescope has perfect optics there are still problems with the quality of its optical path. The optical path includes not only the interior of the telescope, but also the immediate interface between the telescope and the atmosphere, and finally the atmosphere itself

  1. Review of single transient oscillographic recorders with gigahertz bandwidth

    International Nuclear Information System (INIS)

    Campbell, D.E.

    1982-01-01

    In laser driven inertial confinement fusion research, at Livermore, we are diagnosing many phenomena that occur in a time frame that exceeds the capabilities of even the most advanced, present day oscillographic recording instruments. Many of the by-products of the interaction between the laser beam and fuel pellet are monitored to determine the specifics of the fusion process. By the use of appropriate detectors, we convert the information contained in the radiated by-products to electrical signals which are recorded on high bandwidth oscillographic recorders. Our present range of recording capabilities for one x-ray diagnostic measurement in use at Livermore is shown. A commonly used configuration consists of an XRD-31 x-ray detector connected to a direct access Tektronix R7912 transient digitizer using 1/2 in. diameter air dielectric coaxial cable. This configuration gives a system fwhm of approximately 335 ps. Our premier configuration, on the other hand, consists of an improved response detector and a French Thomson-CSF TSN-660 oscilloscope with a shorter length of coaxial cable (typically 20 feet). The system fwhm in this case is less than 120 ps which is our fastest oscillographic recording system at the present time

  2. Standard Specification for Nuclear Facility Transient Worker Records

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1995-01-01

    1.1 This specification covers the required content and provides retention requirements for records needed for in-processing of nuclear facility transient workers. 1.2 This specification applies to records to be used for in-processing only. 1.3 This specification is not intended to cover specific skills records (such as equipment operating licenses, ASME inspection qualifications, or welding certifications). 1.4 This specification does not reduce any regulatory requirement for records retention at a licensed nuclear facility. Note 1—Nuclear facilities operated by the U.S. Department of Energy (DOE) are not licensed by the U.S. Nuclear Regulatory Commission (NRC), nor are other nuclear facilities that may come under the control of the U.S. Department of Defense (DOD) or individual agreement states. The references in this specification to licensee, the U.S. NRC Regulatory Guides, and Title 10 of the U.S. Code of Federal Regulations are to imply appropriate alternative nomenclature with respect to DOE, DOD...

  3. High resolution data acquisition

    Science.gov (United States)

    Thornton, Glenn W.; Fuller, Kenneth R.

    1993-01-01

    A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock (38) pulse train (37) and analog circuitry (44) for generating a triangular wave (46) synchronously with the pulse train (37). The triangular wave (46) has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter (18, 32) forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter (26) counts the clock pulse train (37) during the interval to form a gross event interval time. A computer (52) then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.

  4. ANL high resolution injector

    International Nuclear Information System (INIS)

    Minehara, E.; Kutschera, W.; Hartog, P.D.; Billquist, P.

    1985-01-01

    The ANL (Argonne National Laboratory) high-resolution injector has been installed to obtain higher mass resolution and higher preacceleration, and to utilize effectively the full mass range of ATLAS (Argonne Tandem Linac Accelerator System). Preliminary results of the first beam test are reported briefly. The design and performance, in particular a high-mass-resolution magnet with aberration compensation, are discussed. 7 refs., 5 figs., 2 tabs

  5. Ultra high resolution tomography

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, W.S.

    1994-11-15

    Recent work and results on ultra high resolution three dimensional imaging with soft x-rays will be presented. This work is aimed at determining microscopic three dimensional structure of biological and material specimens. Three dimensional reconstructed images of a microscopic test object will be presented; the reconstruction has a resolution on the order of 1000 A in all three dimensions. Preliminary work with biological samples will also be shown, and the experimental and numerical methods used will be discussed.

  6. High resolution (transformers.

    Science.gov (United States)

    Garcia-Souto, Jose A; Lamela-Rivera, Horacio

    2006-10-16

    A novel fiber-optic interferometric sensor is presented for vibrations measurements and analysis. In this approach, it is shown applied to the vibrations of electrical structures within power transformers. A main feature of the sensor is that an unambiguous optical phase measurement is performed using the direct detection of the interferometer output, without external modulation, for a more compact and stable implementation. High resolution of the interferometric measurement is obtained with this technique (transformers are also highlighted.

  7. High resolution ultrasonic densitometer

    International Nuclear Information System (INIS)

    Dress, W.B.

    1983-01-01

    The velocity of torsional stress pulses in an ultrasonic waveguide of non-circular cross section is affected by the temperature and density of the surrounding medium. Measurement of the transit times of acoustic echoes from the ends of a sensor section are interpreted as level, density, and temperature of the fluid environment surrounding that section. This paper examines methods of making these measurements to obtain high resolution, temperature-corrected absolute and relative density and level determinations of the fluid. Possible applications include on-line process monitoring, a hand-held density probe for battery charge state indication, and precise inventory control for such diverse fluids as uranium salt solutions in accountability storage and gasoline in service station storage tanks

  8. A high-resolution paleosecular variation record from Black Sea sediments indicating fast directional changes associated with low field intensities during marine isotope stage (MIS) 4

    Science.gov (United States)

    Nowaczyk, Norbert R.; Jiabo, Liu; Frank, Ute; Arz, Helge W.

    2018-02-01

    A total of nine sediment cores recovered from the Archangelsky Ridge in the SE Black Sea were systematically subjected to intense paleo- and mineral magnetic analyses. Besides 16 accelerator mass spectrometry (AMS) 14C ages available for another core from this area, dating was accomplished by correlation of short-term warming events during the last glacial monitored by high-resolution X-ray fluorescence (XRF) scanning as maxima in both Ca/Ti and K/Ti ratios in Black Sea sediments to the so-called 'Dansgaard-Oeschger events' recognized from Greenland ice cores. Thus, several hiatuses could be identified in the various cores during the last glacial/interglacial cycle. Finally, core sections documenting marine isotope stage (MIS) 4 at high resolution back to 69 ka were selected for detailed analyses. At 64.5 ka, according to obtained results from Black Sea sediments, the second deepest minimum in relative paleointensity during the past 69 ka occurred, with the Laschamp geomagnetic excursion at 41 ka being associated with the lowest field intensities. The field minimum during MIS 4 is associated with large declination swings beginning about 3 ka before the minimum. While a swing to 50°E is associated with steep inclinations (50-60°) according to the coring site at 42°N, the subsequent declination swing to 30°W is associated with shallow inclinations of down to 40°. Nevertheless, these large deviations from the direction of a geocentric axial dipole field (I = 61 °, D = 0 °) still can not yet be termed as 'excursional', since latitudes of corresponding virtual geomagnetic poles (VGP) only reach down to 51.5°N (120°E) and 61.5°N (75°W), respectively. However, these VGP positions at opposite sides of the globe are linked with VGP drift rates of up to 0.2° per year in between. These extreme secular variations might be the mid-latitude expression of a geomagnetic excursion with partly reversed inclinations found at several sites much further North in Arctic

  9. A High-Resolution Biogenic Silica Record From Lake Titicaca, Peru-Bolivia: South American Millennial-Scale Climate Variability From 18-60 Kya

    Science.gov (United States)

    Ekdahl, E. J.; Fritz, S. C.; Stevens, L. R.; Baker, P. A.; Seltzer, G. O.

    2004-12-01

    Sediments recovered from a deep basin in Lake Titicaca, Peru-Boliva, were analyzed for biogenic silica (BSi) content by extraction of freeze dried sediments in 1% sodium carbonate. Sediments were dated using an age model developed from multiple 14C dates on bulk sediments. The BSi record shows distinct fluctuations in concentration and accumulation rate from 18 to 60 kya. Multi-taper method spectral analysis reveals a significant millennial-scale component to these fluctuations centered at 1370 years. High BSi accumulation rates correlate with enhanced benthic diatom preservation, suggesting that the BSi record is related to variations in lake water level. Modern-day Lake Titicaca lake level and precipitation are strongly related to northern equatorial Atlantic sea surface temperatures, with cooler SSTs related to wetter conditions. Subsequently, the spectral behavior of the GRIP ice core δ 18O record was investigated in order to estimate coherency and linkages between North Atlantic and tropical South American climate. GRIP data exhibit a significant 1370-year spectral peak which comprises approximately 26% of the total variability in the record. Despite a high degree of coherency between millennial-scale periodicities in Lake Titicaca BSi and GRIP δ 18O records, the Lake Titicaca silica record does not show longer term cooling cycles characteristic of D-O cycles found in the GRIP record. Rather, the Lake Titicaca record is highly periodic and more similar in nature to several Antarctic climate proxy records. These results suggest that while South American tropical climate varies in phase with North Atlantic climate, additional forcing mechanisms are manifest in the region which may include tropical Pacific and Southern Ocean variability.

  10. Vital Recorder—a free research tool for automatic recording of high-resolution time-synchronised physiological data from multiple anaesthesia devices

    OpenAIRE

    Lee, Hyung-Chul; Jung, Chul-Woo

    2018-01-01

    The current anaesthesia information management system (AIMS) has limited capability for the acquisition of high-quality vital signs data. We have developed a Vital Recorder program to overcome the disadvantages of AIMS and to support research. Physiological data of surgical patients were collected from 10 operating rooms using the Vital Recorder. The basic equipment used were a patient monitor, the anaesthesia machine, and the bispectral index (BIS) monitor. Infusion pumps, cardiac output mon...

  11. High-resolution records of the beryllium-10 solar activity proxy in ice from Law Dome, East Antarctica: measurement, reproducibility and principal trends

    Directory of Open Access Journals (Sweden)

    J. B. Pedro

    2011-07-01

    Full Text Available Three near-monthly resolution 10Be records are presented from the Dome Summit South (DSS ice core site, Law Dome, East Antarctica. The chemical preparation and Accelerator Mass Spectrometer (AMS measurement of these records is described. The reproducibility of 10Be records at DSS is assessed through intercomparison of the ice core data with data from two previously published and contemporaneous snow pits. We find generally good agreement between the five records, comparable to that observed between other trace chemical records from the site. This result allays concerns raised by a previous Antarctic study (Moraal et al., 2005 about poor reproducibility of ice core 10Be records. A single composite series is constructed from the three ice cores providing a monthly-resolved record of 10Be concentrations at DSS over the past decade (1999 to 2009. To our knowledge, this is the first published ice core data spanning the recent exceptional solar minimum of solar cycle 23. 10Be concentrations are significantly correlated to the cosmic ray flux recorded by the McMurdo neutron monitor (rxy = 0.64, with 95 % CI of 0.53 to 0.71, suggesting that solar modulation of the atmospheric production rate may explain up to ~40 % of the variance in 10Be concentrations at DSS. Sharp concentration peaks occur in most years during the summer-to-autumn, possibly caused by stratospheric incursions. Our results underscore the presence of both production and meteorological signals in ice core 10Be data.

  12. The Valle di Manche section (Calabria, Southern Italy): A high resolution record of the Early-Middle Pleistocene transition (MIS 21-MIS 19) in the Central Mediterranean

    Science.gov (United States)

    Capraro, Luca; Ferretti, Patrizia; Macrì, Patrizia; Scarponi, Daniele; Tateo, Fabio; Fornaciari, Eliana; Bellini, Giulia; Dalan, Giorgia

    2017-06-01

    The on-land marine Valle di Manche section (Crotone Basin, Calabria, Southern Italy), one of the candidates to host the GSSP of the Middle Pleistocene (;Ionian;) Stage, preserves a manifold record of independent chronological, paleoclimatic and stratigraphic proxies that permit a straightforward correlation with marine and terrestrial reference records at the global scale. In particular, the section holds an excellent record of the Matuyama-Brunhes magnetic reversal, which occurs in the midst of Marine Isotope Stage (MIS) 19. We report on a complete revision of the section that improves dramatically the available dataset, especially in the stratigraphic interval straddling the Lower-Middle Pleistocene boundary. Our benthic δ18O record provides evidence that the Matuyama-Brunhes transition, the stratigraphic position of which is marked by a prominent tephra (the ;Pitagora ash;), occurred during full MIS 19, in agreement with many records worldwide. We obtained an age of 786.9 ± 5 ka for the Matuyama-Brunhes magnetic reversal and pinpointed the paleomagnetic transition of to a 3 cm-thick interval, indicating that the event was very fast. Since the section fulfills all the requirements to host the GSSP of the Ionian Stage, we propose that the boundary should be placed at the base of the ;Pitagora ash;, ca. 12.5 cm below the midpoint of the Matuyama-Brunhes reversal.

  13. New high-resolution record of Holocene climate change in the Weddell Sea from combined biomarker analysis of the Patriot Hills blue ice area

    Science.gov (United States)

    Fogwill, Christopher; Turney, Chris; Baker, Andy; Ellis, Bethany; Cooper, Alan; Etheridge, David; Rubino, Mauro; Thornton, David; Fernando, Francisco; Bird, Michale; Munksgaard, Niels

    2017-04-01

    We report preliminary analysis of biomarkers (including dissolved organic matter (DOM) and DNA) from the Patriot Hills blue ice area (BIA), from the Ellsworth Mountains in the Weddell Sea Embayment. Preliminary isotopic and multiple gas analysis (CO2, CH4, N2O and CO) demonstrate that the Holocene comprises more than 50% of the 800m long BIA record, and in combination isotopic and biomarker analysis reveals a remarkable record of centennial variability through the Holocene in this sector of the Weddell Sea. Analysis using a Horiba Aqualog - which measures the fluorescence of DOM by producing a map of the fluorescence through an excitation-emission matrix (EEM) - identifies the presence of two marine protein-like components in both modern snow pit samples and within the Holocene part of Patriot Hills BIA transect. Intriguingly, the modern seasonal trends in DOM, recorded in contemporary snow pits, have relatively low signals compared to those recorded in the mid-Holocene record, suggesting a reduction in DOM signal in contemporary times. Given that the δD excess data suggests the source of precipitation has remained constant through the Holocene, the biomarker signal must relate to multi-year marine productivity signals from the Weddell Sea. The marked variability in DOM between the mid-Holocene and contemporary times can only relate to periods of sustained, enhanced biological productivity in the Weddell Sea associated with shifts in Southern Annular Mode, sea ice variability, changes in ventilation or polynya activity. Here we discuss the possible drivers of these changes and describe how this approach at this BIA could benefit conventional ice core records regionally.

  14. Ultra-high resolution pollen record from the northern Andes reveals rapid shifts in montane climates within the last two glacial cycles

    NARCIS (Netherlands)

    Groot, M.H.M.; Bogotá, R.G.; Lourens, L.J.; Hooghiemstra, H.; Vriend, M.; Berrio, J.C.; Tuenter, E.; Van der Plicht, J.; van Geel, B.; Ziegler, M.; Weber, S.L.; Betancourt, A.; Contreras, L.; Gaviria, S.; Giraldo, C.; González, N.; Jansen, J.H.F.; Konert, M.; Ortega, D.; Rangel, O.; Sarmiento, G.; Vandenberghe, J.; Van der Hammen, T.; van der Linden, M.; Westerhoff, W.

    2011-01-01

    Here we developed a composite pollen-based record of altitudinal vegetation changes from Lake Fuquene (5 degrees N) in Colombia at 2540m elevation. We quantitatively calibrated Arboreal Pollen percentages (AP%) into mean annual temperature (MAT) changes with an unprecedented similar to 60-year

  15. Holocene climate change in North Africa and the end of the African humid period - results of new high-resolution transient simulations with the MPI-ESM 1.3

    Science.gov (United States)

    Dallmeyer, Anne; Claussen, Martin; Lorenz, Stephan

    2017-04-01

    The Max-Planck-Institute for Meteorology has recently undertaken high-resolution transient Holocene simulations using the fully-coupled Earth System Model MPI-ESM 1.3. The simulations cover the last 8000 years and are forced not only by reconstructed Holocene orbital variations and atmospheric greenhouse gas concentrations, but also by recent compilations of Holocene volcanic aerosol distributions, variations in spectral solar irradiance, stratospheric ozone and land-use change. The simulations reveal the ubiquitous "Holocene conundrum": simulated global mean temperatures increase during the mid-Holocene and stay constant during the late Holocene. Simulated mid-Holocene near-surface temperatures are too cold in large parts of the world. Simulated precipitation, however, agrees much better with reconstruction than temperatures do. Likewise simulated global biome pattern fit reconstructions nicely, except for North Western America. First results of these simulations are presented with the main focus on the North African monsoon region. The amplitude of the mid-Holocene African Humid Period (AHP) is well captured in terms of precipitation and vegetation cover, so is the south-ward transgression of the termination of the AHP seen in reconstructions. The Holocene weakening and southward retreat of the North African monsoon as well as changes in the monsoon dynamic including shifts in the seasonal cycle and their relation to the locally varying termination of the AHP are discussed in detail. Members of the Hamburg Holocene Team: Jürgen Bader (1), Sebastian Bathiany (2), Victor Brovkin (1), Martin Claussen (1,3), Traute Crüger (1), Roberta D'agostino (1), Anne Dallmeyer (1), Sabine Egerer (1), Vivienne Groner (1), Matthias Heinze (1), Tatiana Ilyina (1), Johann Jungclaus (1), Thomas Kleinen (1), Alexander Lemburg (1), Stephan Lorenz (1), Thomas Raddatz (1), Hauke Schmidt (1), Gerhard Schmiedl (3), Bjorn Stevens (1), Claudia Timmreck (1), Matthew Toohey (4) (1) Max

  16. An Efficient, Semi-implicit Pressure-based Scheme Employing a High-resolution Finitie Element Method for Simulating Transient and Steady, Inviscid and Viscous, Compressible Flows on Unstructured Grids

    Energy Technology Data Exchange (ETDEWEB)

    Richard C. Martineau; Ray A. Berry

    2003-04-01

    A new semi-implicit pressure-based Computational Fluid Dynamics (CFD) scheme for simulating a wide range of transient and steady, inviscid and viscous compressible flow on unstructured finite elements is presented here. This new CFD scheme, termed the PCICEFEM (Pressure-Corrected ICE-Finite Element Method) scheme, is composed of three computational phases, an explicit predictor, an elliptic pressure Poisson solution, and a semiimplicit pressure-correction of the flow variables. The PCICE-FEM scheme is capable of second-order temporal accuracy by incorporating a combination of a time-weighted form of the two-step Taylor-Galerkin Finite Element Method scheme as an explicit predictor for the balance of momentum equations and the finite element form of a time-weighted trapezoid rule method for the semi-implicit form of the governing hydrodynamic equations. Second-order spatial accuracy is accomplished by linear unstructured finite element discretization. The PCICE-FEM scheme employs Flux-Corrected Transport as a high-resolution filter for shock capturing. The scheme is capable of simulating flows from the nearly incompressible to the high supersonic flow regimes. The PCICE-FEM scheme represents an advancement in mass-momentum coupled, pressurebased schemes. The governing hydrodynamic equations for this scheme are the conservative form of the balance of momentum equations (Navier-Stokes), mass conservation equation, and total energy equation. An operator splitting process is performed along explicit and implicit operators of the semi-implicit governing equations to render the PCICE-FEM scheme in the class of predictor-corrector schemes. The complete set of semi-implicit governing equations in the PCICE-FEM scheme are cast in this form, an explicit predictor phase and a semi-implicit pressure-correction phase with the elliptic pressure Poisson solution coupling the predictor-corrector phases. The result of this predictor-corrector formulation is that the pressure Poisson

  17. High-Resolution Source Parameter and Site Characteristics Using Near-Field Recordings - Decoding the Trade-off Problems Between Site and Source

    Science.gov (United States)

    Chen, X.; Abercrombie, R. E.; Pennington, C.

    2017-12-01

    Recorded seismic waveforms include contributions from earthquake source properties and propagation effects, leading to long-standing trade-off problems between site/path effects and source effects. With near-field recordings, the path effect is relatively small, so the trade-off problem can be simplified to between source and site effects (commonly referred as "kappa value"). This problem is especially significant for small earthquakes where the corner frequencies are within similar ranges of kappa values, so direct spectrum fitting often leads to systematic biases due to corner frequency and magnitude. In response to the significantly increased seismicity rate in Oklahoma, several local networks have been deployed following major earthquakes: the Prague, Pawnee and Fairview earthquakes. Each network provides dense observations within 20 km surrounding the fault zone, recording tens of thousands of aftershocks between M1 to M3. Using near-field recordings in the Prague area, we apply a stacking approach to separate path/site and source effects. The resulting source parameters are consistent with parameters derived from ground motion and spectral ratio methods from other studies; they exhibit spatial coherence within the fault zone for different fault patches. We apply these source parameter constraints in an analysis of kappa values for stations within 20 km of the fault zone. The resulting kappa values show significantly reduced variability compared to those from direct spectral fitting without constraints on the source spectrum; they are not biased by earthquake magnitudes. With these improvements, we plan to apply the stacking analysis to other local arrays to analyze source properties and site characteristics. For selected individual earthquakes, we will also use individual-pair empirical Green's function (EGF) analysis to validate the source parameter estimations.

  18. A 20-15 ka high-resolution paleomagnetic secular variation record from Black Sea sediments - no evidence for the 'Hilina Pali excursion'?

    Science.gov (United States)

    Liu, Jiabo; Nowaczyk, Norbert R.; Frank, Ute; Arz, Helge W.

    2018-06-01

    A comprehensive magnetostratigraphic investigation on sixteen sediment cores from the southeastern Black Sea yielded a very detailed high-quality paleosecular variation (PSV) record spanning from 20 to 15 ka. The age models are based on radiocarbon dating, stratigraphic correlation, and tephrochronology. Further age constraints were obtained by correlating four meltwater events, described from the western Black Sea, ranging in age from about 17 to 15 ka, with maxima in K/Ti ratios, obtained from X-ray fluorescence (XRF) scanning, and minima in S-ratios, reflecting increased hematite content, in the studied cores. Since the sedimentation rates in the investigated time window are up to 50 cm ka-1, the obtained PSVs records enabled a stacking using 50-yr bins. A directional anomaly at 18.5 ka, associated with pronounced swings in inclination and declination, as well as a low in relative paleointensity (rPI), is probably contemporaneous with the Hilina Pali excursion, originally reported from Hawaiian lava flows. However, virtual geomagnetic poles (VGPs) calculated from Black Sea sediments are not located at latitudes lower than 60°N, which denotes normal, though pronounced secular variations. During the postulated Hilina Pali excursion, the VGPs calculated from Black Sea data migrated clockwise only along the coasts of the Arctic Ocean from NE Canada (20.0 ka), via Alaska (18.6 ka) and NE Siberia (18.0 ka) to Svalbard (17.0 ka), then looping clockwise through the Eastern Arctic Ocean.

  19. High-speed, random-access fluorescence microscopy: I. High-resolution optical recording with voltage-sensitive dyes and ion indicators.

    Science.gov (United States)

    Bullen, A; Patel, S S; Saggau, P

    1997-07-01

    The design and implementation of a high-speed, random-access, laser-scanning fluorescence microscope configured to record fast physiological signals from small neuronal structures with high spatiotemporal resolution is presented. The laser-scanning capability of this nonimaging microscope is provided by two orthogonal acousto-optic deflectors under computer control. Each scanning point can be randomly accessed and has a positioning time of 3-5 microseconds. Sampling time is also computer-controlled and can be varied to maximize the signal-to-noise ratio. Acquisition rates up to 200k samples/s at 16-bit digitizing resolution are possible. The spatial resolution of this instrument is determined by the minimal spot size at the level of the preparation (i.e., 2-7 microns). Scanning points are selected interactively from a reference image collected with differential interference contrast optics and a video camera. Frame rates up to 5 kHz are easily attainable. Intrinsic variations in laser light intensity and scanning spot brightness are overcome by an on-line signal-processing scheme. Representative records obtained with this instrument by using voltage-sensitive dyes and calcium indicators demonstrate the ability to make fast, high-fidelity measurements of membrane potential and intracellular calcium at high spatial resolution (2 microns) without any temporal averaging.

  20. Concurrent and opposed environmental trends during the last glacial cycle between the Carpathian Basin and the Black Sea coast: evidence from high resolution enviromagnetic loess records

    Science.gov (United States)

    Hambach, Ulrich; Zeeden, Christian; Veres, Daniel; Obreht, Igor; Bösken, Janina; Marković, Slobodan B.; Eckmeier, Eileen; Fischer, Peter; Lehmkuhl, Frank

    2015-04-01

    Aeolian dust sediments (loess) are beside marine/lacustrine sediments, speleothemes and arctic ice cores the key archives for the reconstruction of the Quaternary palaeoenvironment in the Eurasian continental mid-latitudes. The Eurasian loess-belt has its western end in the Middle (Carpathian) and the Lower Danube Basin where one can find true loess plateaus dating back more than one million years and comprising a semi-continuous record of Pleistocene environmental change. The loess-palaeosol sequences (LPSS) of the region allow inter-regional and trans-regional comparison and, even more importantly, the analysis of temporal and spatial trends in Pleistocene environments, even on a hemispheric scale. However, the general temporal resolution of the LPSS seems mostly limited to the orbital scale patterns, enabling the general comparision of their well documented palaeoclimate record to the marine isotope stages (MIS) and thus to the course of the global ice volume with time. Following the widespread conventional wisdom in loess research, cold and more importantly dry conditions are generally assumed to lead to relatively high accumulation rates of loess, whereas during warmer and more humid environmental conditions the vegetation cover prevents ablation and clastic silt production. Moreover, synsedimentary pedogenesis prevails and hence, (embryonic) soils are formed which are rapidly buried by loess as soon as the climate returns to drier conditions. In the last decades, mineral magnetic parameters became fundamental palaeoclimate proxies in loess research. The magnetic susceptibility (χ) and its dependence on the frequency of the applied field (χfd) turned out to be beside grain size and geochemical indices a highly sensitive proxy especially for soil humidity during loess accumulation. Here we present the first results of an ongoing study on two Late Pleistocene LPSS from the southern Carpathian Basin (Titel-Plateau, Vojvodina, Serbia) and the eastern Lower

  1. A High-Resolution ENSO-Driven Rainfall Record Derived From an Exceptionally Fast Growing Stalagmite From Niue Island (South Pacific)

    Science.gov (United States)

    Troy, S.; Aharon, P.; Lambert, W. J.

    2012-12-01

    El Niño-Southern Oscillation's (ENSO) dominant control over the present global climate and its unpredictable response to a global warming makes the study of paleo-ENSO important. So far corals, spanning the Tropical Pacific Ocean, are the most commonly used geological archives of paleo-ENSO. This is because corals typically exhibit high growth rates (>1 cm/yr), and reproduce reliably surface water temperatures at sub-annual resolution. However there are limitations to coral archives because their time span is relatively brief (in the order of centuries), thus far making a long and continuous ENSO record difficult to achieve. On the other hand stalagmites from island settings can offer long and continuous records of ENSO-driven rainfall. Niue Island caves offer an unusual opportunity to investigate ENSO-driven paleo-rainfall because the island is isolated from other large land masses, making it untainted by continental climate artifacts, and its geographical location is within the Tropical Pacific "rain pool" (South Pacific Convergence Zone; SPCZ) that makes the rainfall variability particularly sensitive to the ENSO phase switches. We present here a δ18O and δ13C time series from a stalagmite sampled on Niue Island (19°00' S, 169°50' W) that exhibits exceptionally high growth rates (~1.2 mm/yr) thus affording a resolution comparable to corals but for much longer time spans. A precise chronology, dating back to several millennia, was achieved by U/Th dating of the stalagmite. The stalagmite was sampled using a Computer Automated Mill (CAM) at 300 μm increments in order to receive sub-annual resolution (every 3 months) and calcite powders of 50-100 μg weight were analyzed for δ18O and δ13C using a Continuous Flow Isotope Ratio Mass Spectrometer (CF-IRMS). The isotope time series contains variable shifts at seasonal, inter-annual, and inter-decadal periodicities. The δ13C and δ18O yield ranges of -3.0 to -13.0 (‰ VPDB) and -3.2 to -6.2 (‰ VPDB

  2. High-resolution sub-bottom seismic and sediment core records from the Chukchi Abyssal Plain reveal Quaternary glaciation impacts on the western Arctic Ocean

    Science.gov (United States)

    Joe, Y. J.; Seokhoon, Y.; Nam, S. I.; Polyak, L.; Niessen, F.

    2017-12-01

    For regional context of the Quaternary history of Arctic marine glaciations, such as glacial events in northern North America and on the Siberian and Chukchi margins, we used CHIRP sub-bottom profiles (SBP) along with sediment cores, including a 14-m long piston core ARA06-04JPC taken from the Chukchi abyssal plain during the RV Araon expedition in 2015. Based on core correlation with earlier developed Arctic Ocean stratigraphies using distribution of various sedimentary proxies, core 04JPC is estimated to extend to at least Marine Isotope Stage 13 (>0.5 Ma). The stratigraphy developed for SBP lines from the Chukchi abyssal plain to surrounding slopes can be divided into four major seismostratigraphic units (SSU 1-4). SBP records from the abyssal plain show well preserved stratification, whereas on the surrounding slopes this pattern is disrupted by lens-shaped, acoustically transparent sedimentary bodies interpreted as glaciogenic debris flow deposits. Based on the integration of sediment physical property and SBP data, we conclude that these debris flows were generated during several ice-sheet grounding events on the Chukchi and East Siberian margins, including adjacent ridges and plateaus, during the middle to late Quaternary.

  3. A new technique for obtaining high-resolution pore pressure records in thick claystone aquitards and its use to determine in situ compressibility

    Science.gov (United States)

    Smith, Laura A.; van der Kamp, Garth; Jim Hendry, M.

    2013-02-01

    Laboratory tests are commonly used to determine properties (vertical compressibility, α; specific storage, SS; and vertical hydraulic conductivity, Kv) of claystone aquitards; however, whether data representative of in situ conditions can be obtained from disturbed samples is questionable. Here, we present a method to determine the in situ α and SS of a thick sequence of Cretaceous aged claystone by estimating the loading efficiency (γ) of a formation from pore pressure responses to barometric pressure fluctuations. We installed 10 vibrating wire pressure transducers at different depths (25-325 m below ground) in a thick claystone aquitard by placing them directly within the cement-bentonite grout. Two years of continuous transducer records using this method appeared to provide pore pressure data with a resolution of better than one part in 105, equivalent to millimeter of hydraulic head change. Pore pressure responses to barometric pressure changes, earth tides, and precipitation events can be clearly identified, and the barometric responses can be easily analyzed. The resulting values of γ (0.6-0.93), α (2.5 × 10-7 to 2.2 × 10-6 kPa-1), and SS (2.6 × 10-5 to 4.5 × 10-6 m-1) all decrease with depth. The results are comparable with the limited existing data for in situ estimates of SS and are as much as an order of magnitude smaller than laboratory estimates of SS for similar aquitard deposits. Our findings suggest that the fully grouted transducer method can provide an accurate and reliable means to monitor pore pressure changes and to determine in situ parameters for bedrock aquitard systems.

  4. Late Pleistocene and Holocene paleoclimate and alpine glacier fluctuations recorded by high-resolution grain-size data from an alpine lake sediment core, Wind River Range, Wyoming, USA

    Science.gov (United States)

    Thompson Davis, P.; Machalett, Björn; Gosse, John

    2013-04-01

    Varved lake sediments, which provide ideal high-resolution climate proxies, are not commonly available in many geographic areas over long time scales. This paper utilizes high-resolution grain-size analyses (n = 1040) from a 520-cm long sediment core from Lower Titcomb Lake (LTL), which lies just outside the type Titcomb Basin (TTB) moraines in the Wind River Range, Wyoming. The TTB moraines lie between Lower Titcomb Lake and Upper Titcomb Lake (UTL), about 3 km beyond, and 200 m lower than the modern glacier margin and Gannett Peak (Little Ice Age) moraines in the basin. Based on cosmogenic exposure dating, the TTB moraines are believed to be Younger Dryas (YD) age (Gosse et al., 1995) and lie in a geomorphic position similar to several other outer cirque moraines throughout the western American Cordillera. Until recently, many of these outer cirque moraines were believed to be Neoglacial age. The sediment core discussed here is one of five obtained from the two Titcomb Lakes, but is by the far the longest with the oldest sediment depositional record. Two AMS radiocarbon ages from the 445- and 455-cm core depths (about 2% loss on ignition, LOI) suggest that the lake basin may have been ice-free as early as 16.1 or even 16.8 cal 14C kyr, consistent with 10Be and 26Al exposure ages from boulders and bedrock surfaces outside the TTB moraines. The 257-cm depth in the core marks an abrupt transition from inorganic, sticky gray silt below (rock flour production between the 257 and 466 cm core depths appear to be roughly correlative with the YD-Alleröd-Bölling-Meiendorf-Heinrich 1 climate events recognized in other terrestrial records and Northern Atlantic Ocean marine cores, but provide much higher resolution than most of those records from a climate-sensitive alpine region in North America.

  5. High-resolution provenance of desert dust deposited on Mt. Elbrus, Caucasus in 2009–2012 using snow pit and firn core records

    Directory of Open Access Journals (Sweden)

    S. Kutuzov

    2013-09-01

    Full Text Available The first record of dust deposition events on Mt. Elbrus, Caucasus Mountains derived from a snow pit and a shallow firn core is presented for the 2009–2012 period. A combination of isotopic analysis, SEVIRI red-green-blue composite imagery, MODIS atmospheric optical depth fields derived using the Deep Blue algorithm, air mass trajectories derived using the HYSPLIT model and analyses of meteorological data enabled identification of dust source regions with high temporal (hours and spatial (ca. 20–100 km resolution. Seventeen dust deposition events were detected; fourteen occurred in March–June, one in February and two in October. Four events originated in the Sahara, predominantly in northeastern Libya and eastern Algeria. Thirteen events originated in the Middle East, in the Syrian Desert and northern Mesopotamia, from a mixture of natural and anthropogenic sources. Dust transportation from Sahara was associated with vigorous Saharan depressions, strong surface winds in the source region and mid-tropospheric southwesterly flow with daily winds speeds of 20–30 m s−1 at 700 hPa level. Although these events were less frequent than those originating in the Middle East, they resulted in higher dust concentrations in snow. Dust transportation from the Middle East was associated with weaker depressions forming over the source region, high pressure centred over or extending towards the Caspian Sea and a weaker southerly or southeasterly flow towards the Caucasus Mountains with daily wind speeds of 12–18 m s−1 at 700 hPa level. Higher concentrations of nitrates and ammonium characterised dust from the Middle East deposited on Mt. Elbrus in 2009 indicating contribution of anthropogenic sources. The modal values of particle size distributions ranged between 1.98 μm and 4.16 μm. Most samples were characterised by modal values of 2.0–2.8 μm with an average of 2.6 μm and there was no significant difference between dust from the Sahara and

  6. High resolution stable isotopes and elemental analysis on benthic foraminifera: a 4000 yr BP record from the ria de Muros (NW Spain)

    Science.gov (United States)

    Pena, L. D.; Francés, G.; Diz, P.; Nombela, M. A.; Alejo, I.

    2003-04-01

    Carbon and oxygen stable isotopes and ICP-OES elemental ratio concentrations (Mg/Ca, Sr/Ca, Ba/Ca) from core EUGC-3B (42 45.10'N; 9 02.23'W, at 38 m.b.s.l. and 410 cm length) were measured over monospecific benthic foraminiferal samples (Nonion fabum) ranging over the last 4500 yr BP. From the oldest analysed sample (289 cm) to the core top, stable isotopes signal shows that the whole record can be separated into 4 intervals lasting each of them about 1000 yr. The lowermost interval (4300-3000 yr BP) is characterized by relatively stable delta 18O values (mean 1.77 per mil). Delta 13C is relatively low except for a maximum around 3300 cal BP (-1.50 per mil). An abrupt decrease down to the minimum value in delta 13C (-4.41 per mil) is accomplished in approximately 200 yr. Mg/Ca and Ba/Ca match perfectly this event, both of them showing the respective maxima values. Sr/Ca has a very similar behaviour to that of delta 13C but with smoother fluctuations. We attribute high values of delta 13C, Sr/Ca and Ba/Ca to periods of enhanced coastal productivity, probably due to reinforced upwelling events in the region. According to Mg/Ca signal this reinforcement took place during a relatively warmer period. The most remarkable feature during the two next periods (3000-1900 yr BP and 1900-1000 yr BP) consists of a stepwise increase of delta 13C values punctuated by a sharp decrease at the end of each interval. All the remaining proxies exhibit a nearly constant trend over these intervals. Each period can be interpreted as a weak enhance of marine productivity that the system does not hold up and finally aborts. The most recent interval represents the establishment of current conditions in the coastal system. The most conspicuous event from this interval consists of an abrupt decrease of the delta 18O that lasted for 300 yr. This event could be correlated with the well recognized warm climatic event known as the Medieval Warm Period. However the Mg/Ca ratio does not show high

  7. Berkeley High-Resolution Ball

    International Nuclear Information System (INIS)

    Diamond, R.M.

    1984-10-01

    Criteria for a high-resolution γ-ray system are discussed. Desirable properties are high resolution, good response function, and moderate solid angle so as to achieve not only double- but triple-coincidences with good statistics. The Berkeley High-Resolution Ball involved the first use of bismuth germanate (BGO) for anti-Compton shield for Ge detectors. The resulting compact shield permitted rather close packing of 21 detectors around a target. In addition, a small central BGO ball gives the total γ-ray energy and multiplicity, as well as the angular pattern of the γ rays. The 21-detector array is nearly complete, and the central ball has been designed, but not yet constructed. First results taken with 9 detector modules are shown for the nucleus 156 Er. The complex decay scheme indicates a transition from collective rotation (prolate shape) to single- particle states (possibly oblate) near spin 30 h, and has other interesting features

  8. High resolution metric imaging payload

    Science.gov (United States)

    Delclaud, Y.

    2017-11-01

    Alcatel Space Industries has become Europe's leader in the field of high and very high resolution optical payloads, in the frame work of earth observation system able to provide military government with metric images from space. This leadership allowed ALCATEL to propose for the export market, within a French collaboration frame, a complete space based system for metric observation.

  9. 8-bit serial-parallel analog-to-digital converter for fast transient recorder

    International Nuclear Information System (INIS)

    Kulka, Z.; Nadachowski, M.; Zimek, Z.

    1990-08-01

    An 8-bit serial-parallel analog-to-digital converter with a sampling frequency 5 MHz is described. The most important circuits of the device are described and parameters are given. The converter is a central part of a transient recorder type TR-1 designed for recording pulse waveforms in measurements of the kinetics of chemical reactions which are radiation-induced using an electron linear accelerator. 9 refs., 9 figs. (author)

  10. Measurement of radiation induced transients in hybrid microcircuits by magnetic thin film sensor/recorders

    International Nuclear Information System (INIS)

    Hsieh, E.J.; Vindelov, K.E.; Brown, T.G.; Miller, D.E.

    1976-01-01

    Magnetic thin film transient current sensor/recorders were modified to make two types of nuclear test measurements, transient currents in hybrid microcircuits and internal electromagnetic pulse (IEMP) fields. The measurements were made possible by the invention of split-domain sensor/recorders which can measure bilateral currents and can be reset and readout on location. The sensor/recorders were used in two underground nuclear tests and numerous calibration tests in radiation-simulation machines. The data showed that the nuclear environment had negligible effect on the sensor/recorder's operation and the recorded informations on the sensor/recorders were the signals intended to be monitored. Also, the experimental data agreed with the theoretical analysis in controlled experiments. The data were examined first by on location readout with a magnetic tape viewer and later by Kerr magneto-optic readout in the laboratory. To translate the data into current readings, we reconstructed facsimile data (on each of the sensor/recorders) in the laboratory by current pulses with the same pulse width as the radiation event. An additional check on the accuracy of the data was made by using both the sensor/recorder and the conventional pickup-oscilloscope-camera technique to monitor the same current lead in a simulated radiation environment. Over five runs were made, and the agreement among the two measurement methods was within 25%. The data collectively implied that the measurements were reliable and dependable

  11. High-resolution spectroscopic probes of collisions and half-collisions

    Energy Technology Data Exchange (ETDEWEB)

    Hall, G.E. [Brookhaven National Laboratory, Upton, NY (United States)

    1993-12-01

    Research in this program explores the dynamics of gas phase collisions and photodissociation by high-resolution laser spectroscopy. Simultaneous state and velocity detection frequently permits a determination of scalar or vector correlations among products. The correlated product distributions are always more informative, and often easier to interpret than the uncorrelated product state distributions. The authors have recently built an apparatus to record transient absorption spectra with 50 nS time resolution and 20 MHz frequency resolution using a single frequency Ti:sapphire laser. The photodissociation of NCCN and C{sub 2}H{sub 5}SCN at 193 nm is discussed.

  12. High-resolution three-dimensional imaging of a depleted CMOS sensor using an edge Transient Current Technique based on the Two Photon Absorption process (TPA-eTCT)

    CERN Document Server

    García, Marcos Fernández; Echeverría, Richard Jaramillo; Moll, Michael; Santos, Raúl Montero; Moya, David; Pinto, Rogelio Palomo; Vila, Iván

    2016-01-01

    For the first time, the deep n-well (DNW) depletion space of a High Voltage CMOS sensor has been characterized using a Transient Current Technique based on the simultaneous absorption of two photons. This novel approach has allowed to resolve the DNW implant boundaries and therefore to accurately determine the real depleted volume and the effective doping concentration of the substrate. The unprecedented spatial resolution of this new method comes from the fact that measurable free carrier generation in two photon mode only occurs in a micrometric scale voxel around the focus of the beam. Real three-dimensional spatial resolution is achieved by scanning the beam focus within the sample.

  13. High-resolution three-dimensional imaging of a depleted CMOS sensor using an edge Transient Current Technique based on the Two Photon Absorption process (TPA-eTCT)

    Energy Technology Data Exchange (ETDEWEB)

    García, Marcos Fernández; Sánchez, Javier González; Echeverría, Richard Jaramillo [Instituto de Física de Cantabria (CSIC-UC), Avda. los Castros s/n, E-39005 Santander (Spain); Moll, Michael [CERN, Organisation europénne pour la recherche nucléaire, CH-1211 Genéve 23 (Switzerland); Santos, Raúl Montero [SGIker Laser Facility, UPV/EHU, Sarriena, s/n - 48940 Leioa-Bizkaia (Spain); Moya, David [Instituto de Física de Cantabria (CSIC-UC), Avda. los Castros s/n, E-39005 Santander (Spain); Pinto, Rogelio Palomo [Departamento de Ingeniería Electrónica, Escuela Superior de Ingenieros Universidad de Sevilla (Spain); Vila, Iván [Instituto de Física de Cantabria (CSIC-UC), Avda. los Castros s/n, E-39005 Santander (Spain)

    2017-02-11

    For the first time, the deep n-well (DNW) depletion space of a High Voltage CMOS sensor has been characterized using a Transient Current Technique based on the simultaneous absorption of two photons. This novel approach has allowed to resolve the DNW implant boundaries and therefore to accurately determine the real depleted volume and the effective doping concentration of the substrate. The unprecedented spatial resolution of this new method comes from the fact that measurable free carrier generation in two photon mode only occurs in a micrometric scale voxel around the focus of the beam. Real three-dimensional spatial resolution is achieved by scanning the beam focus within the sample.

  14. An absolutely dated high-resolution stalagmite record from Lianhua Cave in central China: Climate forcing and comparison with Wanxiang Cave and Dongge Cave records over the past 2000 years

    Science.gov (United States)

    Li, Hong-Chun; Yin, Jian-Jun; Shen, Chuan-Chou; Mii, Horng-Sheng; Li, Ting-Yong

    2015-04-01

    A 33-cm long aragonite stalagmite (LHD-1) from Lianhua Cave has been dated by MC-ICPMS 230Th/U method on 41 horizons. Very high U contents (1~6ppm) and low Th contents yield excellent 230Th/U dates which provide reliable chronology of the stalagmite on sub-decadal time scale over the past 3350 years. A total of 1716 samples have been measured for δ18O and δ13C, spanning annual resolution over the past 1820 years. The stalagmite δ18O is not only influenced by the 'amount effect', but also affected by the moisture source. Enhanced the tropical monsoon trough under strong EASM brings higher spring quarter rainfall with isotopically light monsoonal moisture in the cave site, resulting in lighter stalagmite δ18O. On decadal or longer time scales, increased solar activity produces warmer condition and stronger summer monsoon which lead to wet climates. On interannual-to-decadal scales, the Walker Circulation under El Niño conditions during cold periods will shift toward the central Pacific and result in weakening of EASM. Under such a circumstance, dry climates will be prevailed in the study area. Based on the δ18O and δ13C records, we have deciphered climatic and vegetation changes of the study area in decadal scales. The highly precise dated LHD-1 record has been compared with previous published Wanxiang Cave and Dongge Cave records. Although some similarities can be found, there are major discrepancies among the three well-dated records, especially during AD 500-700 and AD 1300-1600. In additional, the major weak monsoon periods defined in the Wanxiang Cave record during late Tang Dynasty, late Yuan Dynasty and late Ming Dynasty are not supported by the LHD-1 record. The heaviest δ18O peaks (more than five continuous heavy values) over the past 2000 years appeared around AD 1990-2003, 1657-1662, 1220-1228, 663-669, 363-370, and 1082-1090 (in the order of heavy to light). None of these periods occurred Chinese dynasty collapse.

  15. Methodology of high-resolution photography for mural condition database

    Science.gov (United States)

    Higuchi, R.; Suzuki, T.; Shibata, M.; Taniguchi, Y.

    2015-08-01

    Digital documentation is one of the most useful techniques to record the condition of cultural heritage. Recently, high-resolution images become increasingly useful because it is possible to show general views of mural paintings and also detailed mural conditions in a single image. As mural paintings are damaged by environmental stresses, it is necessary to record the details of painting condition on high-resolution base maps. Unfortunately, the cost of high-resolution photography and the difficulty of operating its instruments and software have commonly been an impediment for researchers and conservators. However, the recent development of graphic software makes its operation simpler and less expensive. In this paper, we suggest a new approach to make digital heritage inventories without special instruments, based on our recent our research project in Üzümlü church in Cappadocia, Turkey. This method enables us to achieve a high-resolution image database with low costs, short time, and limited human resources.

  16. High-resolution esophageal pressure topography for esophageal motility disorders

    OpenAIRE

    Hashem Fakhre Yaseri; Gholamreza Hamsi; Tayeb Ramim

    2016-01-01

    Background: High-resolution manometer (HRM) of the esophagus has become the main diagnostic test in the evaluation of esophageal motility disorders. The development of high-resolution manometry catheters and software displays of manometry recordings in color-coded pressure plots have changed the diagnostic assessment of esophageal disease. The first step of the Chicago classification described abnormal esophagogastric junction deglutitive relaxation. The latest classification system, proposed...

  17. High-resolution ultrasonic spectroscopy

    Directory of Open Access Journals (Sweden)

    V. Buckin

    2018-03-01

    Full Text Available High-resolution ultrasonic spectroscopy (HR-US is an analytical technique for direct and non-destructive monitoring of molecular and micro-structural transformations in liquids and semi-solid materials. It is based on precision measurements of ultrasonic velocity and attenuation in analysed samples. The application areas of HR-US in research, product development, and quality and process control include analysis of conformational transitions of polymers, ligand binding, molecular self-assembly and aggregation, crystallisation, gelation, characterisation of phase transitions and phase diagrams, and monitoring of chemical and biochemical reactions. The technique does not require optical markers or optical transparency. The HR-US measurements can be performed in small sample volumes (down to droplet size, over broad temperature range, at ambient and elevated pressures, and in various measuring regimes such as automatic temperature ramps, titrations and measurements in flow.

  18. High Resolution Thermometry for EXACT

    Science.gov (United States)

    Panek, J. S.; Nash, A. E.; Larson, M.; Mulders, N.

    2000-01-01

    High Resolution Thermometers (HRTs) based on SQUID detection of the magnetization of a paramagnetic salt or a metal alloy has been commonly used for sub-nano Kelvin temperature resolution in low temperature physics experiments. The main applications to date have been for temperature ranges near the lambda point of He-4 (2.177 K). These thermometers made use of materials such as Cu(NH4)2Br4 *2H2O, GdCl3, or PdFe. None of these materials are suitable for EXACT, which will explore the region of the He-3/He-4 tricritical point at 0.87 K. The experiment requirements and properties of several candidate paramagnetic materials will be presented, as well as preliminary test results.

  19. A 13000-year, high-resolution multi-proxy record of climate variability with episodes of enhanced atmospheric dust in Western Asia: Evidence from Neor peat complex in NW Iran

    Science.gov (United States)

    Sharifi, O.; Pourmand, A.; Canuel, E. A.; Peterson, L. C.

    2011-12-01

    The regional climate over West Asia, extending between Iran and the Arabian Peninsula to the eastern Mediterranean Sea, is governed by interactions between three major synoptic systems; mid-latitude Westerlies, the Siberian Anticyclone and the Indian Ocean Summer Monsoon. In recent years, a number of paleoclimate studies have drawn potential links between episodes of abrupt climate change during the Holocene, and the rise and fall of human civilizations across the "Fertile Crescent" of West Asia. High-resolution archives of climate variability from this region, however, are scarce, and at times contradicting. For example, while pollen and planktonic data from lakes in Turkey and Iran suggest that dry, continental conditions prevailed during the early-middle Holocene, oxygen isotope records indicate that relatively wet conditions dominated during this interval over West Asia. We present interannual to decadal multi-proxy records of climate variability from a peat complex in NW Iran to reconstruct changes in moisture and atmospheric dust content during the last 13000 years. Radiocarbon dating on 20 samples from a 775-cm peat core show a nearly constant rate of accumulation (1.7 mm yr-1, R2=0.99) since 13356 ± 116 cal yr B.P. Down-core X-ray fluorescence measurements of conservative lithogenic elements (e.g., Al, Zr, Ti) as well as redox-sensitive elements (e.g., Fe, K, Rb, Zn, Cu, and Co) at 2 mm intervals reveal several periods of elevated dust input to this region since the early Holocene. Down-core variations of total organic carbon and total nitrogen co-vary closely and are inversely correlated with conservative lithogenic elements (Al, Si, Ti), indicating a potential link between climate change and accumulation of organic carbon in the Neor peat mire. Major episodes of enhanced dust deposition (13000-12000, 11700-11200, 9200-8800, 7000-6000, 4200-3200, 2800-2200 and 1500-600 cal yr B.P) are in good agreement with other proxy records that document more arid

  20. High resolution tomographic instrument development

    International Nuclear Information System (INIS)

    1992-01-01

    Our recent work has concentrated on the development of high-resolution PET instrumentation reflecting in part the growing importance of PET in nuclear medicine imaging. We have developed a number of positron imaging instruments and have the distinction that every instrument has been placed in operation and has had an extensive history of application for basic research and clinical study. The present program is a logical continuation of these earlier successes. PCR-I, a single ring positron tomograph was the first demonstration of analog coding using BGO. It employed 4 mm detectors and is currently being used for a wide range of biological studies. These are of immense importance in guiding the direction for future instruments. In particular, PCR-II, a volume sensitive positron tomograph with 3 mm spatial resolution has benefited greatly from the studies using PCR-I. PCR-II is currently in the final stages of assembly and testing and will shortly be placed in operation for imaging phantoms, animals and ultimately humans. Perhaps the most important finding resulting from our previous study is that resolution and sensitivity must be carefully balanced to achieve a practical high resolution system. PCR-II has been designed to have the detection characteristics required to achieve 3 mm resolution in human brain under practical imaging situations. The development of algorithms by the group headed by Dr. Chesler is based on a long history of prior study including his joint work with Drs. Pelc and Reiderer and Stearns. This body of expertise will be applied to the processing of data from PCR-II when it becomes operational

  1. High resolution tomographic instrument development

    Energy Technology Data Exchange (ETDEWEB)

    1992-08-01

    Our recent work has concentrated on the development of high-resolution PET instrumentation reflecting in part the growing importance of PET in nuclear medicine imaging. We have developed a number of positron imaging instruments and have the distinction that every instrument has been placed in operation and has had an extensive history of application for basic research and clinical study. The present program is a logical continuation of these earlier successes. PCR-I, a single ring positron tomograph was the first demonstration of analog coding using BGO. It employed 4 mm detectors and is currently being used for a wide range of biological studies. These are of immense importance in guiding the direction for future instruments. In particular, PCR-II, a volume sensitive positron tomograph with 3 mm spatial resolution has benefited greatly from the studies using PCR-I. PCR-II is currently in the final stages of assembly and testing and will shortly be placed in operation for imaging phantoms, animals and ultimately humans. Perhaps the most important finding resulting from our previous study is that resolution and sensitivity must be carefully balanced to achieve a practical high resolution system. PCR-II has been designed to have the detection characteristics required to achieve 3 mm resolution in human brain under practical imaging situations. The development of algorithms by the group headed by Dr. Chesler is based on a long history of prior study including his joint work with Drs. Pelc and Reiderer and Stearns. This body of expertise will be applied to the processing of data from PCR-II when it becomes operational.

  2. High resolution tomographic instrument development

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    Our recent work has concentrated on the development of high-resolution PET instrumentation reflecting in part the growing importance of PET in nuclear medicine imaging. We have developed a number of positron imaging instruments and have the distinction that every instrument has been placed in operation and has had an extensive history of application for basic research and clinical study. The present program is a logical continuation of these earlier successes. PCR-I, a single ring positron tomograph was the first demonstration of analog coding using BGO. It employed 4 mm detectors and is currently being used for a wide range of biological studies. These are of immense importance in guiding the direction for future instruments. In particular, PCR-II, a volume sensitive positron tomograph with 3 mm spatial resolution has benefited greatly from the studies using PCR-I. PCR-II is currently in the final stages of assembly and testing and will shortly be placed in operation for imaging phantoms, animals and ultimately humans. Perhaps the most important finding resulting from our previous study is that resolution and sensitivity must be carefully balanced to achieve a practical high resolution system. PCR-II has been designed to have the detection characteristics required to achieve 3 mm resolution in human brain under practical imaging situations. The development of algorithms by the group headed by Dr. Chesler is based on a long history of prior study including his joint work with Drs. Pelc and Reiderer and Stearns. This body of expertise will be applied to the processing of data from PCR-II when it becomes operational.

  3. High-Resolution Mass Spectrometers

    Science.gov (United States)

    Marshall, Alan G.; Hendrickson, Christopher L.

    2008-07-01

    Over the past decade, mass spectrometry has been revolutionized by access to instruments of increasingly high mass-resolving power. For small molecules up to ˜400 Da (e.g., drugs, metabolites, and various natural organic mixtures ranging from foods to petroleum), it is possible to determine elemental compositions (CcHhNnOoSsPp…) of thousands of chemical components simultaneously from accurate mass measurements (the same can be done up to 1000 Da if additional information is included). At higher mass, it becomes possible to identify proteins (including posttranslational modifications) from proteolytic peptides, as well as lipids, glycoconjugates, and other biological components. At even higher mass (˜100,000 Da or higher), it is possible to characterize posttranslational modifications of intact proteins and to map the binding surfaces of large biomolecule complexes. Here we review the principles and techniques of the highest-resolution analytical mass spectrometers (time-of-flight and Fourier transform ion cyclotron resonance and orbitrap mass analyzers) and describe some representative high-resolution applications.

  4. Records keeping and control of transient workers' access to vital areas

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The author addresses the following questions: In what ways can the fully developed NEDI best serve the nuclear industry and of what real value is such a system?; What standardizations of the procedures, methods, etc. internal to the individual nuclear plants are desirable or necessary for the NEDI to be most effective? and What standardization of records handling could impose some of the burden and effort on the transient worker himself without undue hardship on him? The author discusses a method used in Europe

  5. High-resolution intravital microscopy.

    Directory of Open Access Journals (Sweden)

    Volker Andresen

    Full Text Available Cellular communication constitutes a fundamental mechanism of life, for instance by permitting transfer of information through synapses in the nervous system and by leading to activation of cells during the course of immune responses. Monitoring cell-cell interactions within living adult organisms is crucial in order to draw conclusions on their behavior with respect to the fate of cells, tissues and organs. Until now, there is no technology available that enables dynamic imaging deep within the tissue of living adult organisms at sub-cellular resolution, i.e. detection at the level of few protein molecules. Here we present a novel approach called multi-beam striped-illumination which applies for the first time the principle and advantages of structured-illumination, spatial modulation of the excitation pattern, to laser-scanning-microscopy. We use this approach in two-photon-microscopy--the most adequate optical deep-tissue imaging-technique. As compared to standard two-photon-microscopy, it achieves significant contrast enhancement and up to 3-fold improved axial resolution (optical sectioning while photobleaching, photodamage and acquisition speed are similar. Its imaging depth is comparable to multifocal two-photon-microscopy and only slightly less than in standard single-beam two-photon-microscopy. Precisely, our studies within mouse lymph nodes demonstrated 216% improved axial and 23% improved lateral resolutions at a depth of 80 µm below the surface. Thus, we are for the first time able to visualize the dynamic interactions between B cells and immune complex deposits on follicular dendritic cells within germinal centers (GCs of live mice. These interactions play a decisive role in the process of clonal selection, leading to affinity maturation of the humoral immune response. This novel high-resolution intravital microscopy method has a huge potential for numerous applications in neurosciences, immunology, cancer research and

  6. High-Resolution Intravital Microscopy

    Science.gov (United States)

    Andresen, Volker; Pollok, Karolin; Rinnenthal, Jan-Leo; Oehme, Laura; Günther, Robert; Spiecker, Heinrich; Radbruch, Helena; Gerhard, Jenny; Sporbert, Anje; Cseresnyes, Zoltan; Hauser, Anja E.; Niesner, Raluca

    2012-01-01

    Cellular communication constitutes a fundamental mechanism of life, for instance by permitting transfer of information through synapses in the nervous system and by leading to activation of cells during the course of immune responses. Monitoring cell-cell interactions within living adult organisms is crucial in order to draw conclusions on their behavior with respect to the fate of cells, tissues and organs. Until now, there is no technology available that enables dynamic imaging deep within the tissue of living adult organisms at sub-cellular resolution, i.e. detection at the level of few protein molecules. Here we present a novel approach called multi-beam striped-illumination which applies for the first time the principle and advantages of structured-illumination, spatial modulation of the excitation pattern, to laser-scanning-microscopy. We use this approach in two-photon-microscopy - the most adequate optical deep-tissue imaging-technique. As compared to standard two-photon-microscopy, it achieves significant contrast enhancement and up to 3-fold improved axial resolution (optical sectioning) while photobleaching, photodamage and acquisition speed are similar. Its imaging depth is comparable to multifocal two-photon-microscopy and only slightly less than in standard single-beam two-photon-microscopy. Precisely, our studies within mouse lymph nodes demonstrated 216% improved axial and 23% improved lateral resolutions at a depth of 80 µm below the surface. Thus, we are for the first time able to visualize the dynamic interactions between B cells and immune complex deposits on follicular dendritic cells within germinal centers (GCs) of live mice. These interactions play a decisive role in the process of clonal selection, leading to affinity maturation of the humoral immune response. This novel high-resolution intravital microscopy method has a huge potential for numerous applications in neurosciences, immunology, cancer research and developmental biology

  7. High-Resolution Integrated Optical System

    Science.gov (United States)

    Prakapenka, V. B.; Goncharov, A. F.; Holtgrewe, N.; Greenberg, E.

    2017-12-01

    transient (based on a bright supercontinuum light source) spectroscopies in a wide spectral range (200-1600 nm). Details and future combination of this innovative system with high-resolution synchrotron micro-diffraction at GSECARS for full characterization of materials in-situ at extreme conditions will be discussed.

  8. Section on High Resolution Optical Imaging (HROI)

    Data.gov (United States)

    Federal Laboratory Consortium — The Section on High Resolution Optical Imaging (HROI) develops novel technologies for studying biological processes at unprecedented speed and resolution. Research...

  9. Transient Structures and Possible Limits of Data Recording in Phase-Change Materials.

    Science.gov (United States)

    Hu, Jianbo; Vanacore, Giovanni M; Yang, Zhe; Miao, Xiangshui; Zewail, Ahmed H

    2015-07-28

    Phase-change materials (PCMs) represent the leading candidates for universal data storage devices, which exploit the large difference in the physical properties of their transitional lattice structures. On a nanoscale, it is fundamental to determine their performance, which is ultimately controlled by the speed limit of transformation among the different structures involved. Here, we report observation with atomic-scale resolution of transient structures of nanofilms of crystalline germanium telluride, a prototypical PCM, using ultrafast electron crystallography. A nonthermal transformation from the initial rhombohedral phase to the cubic structure was found to occur in 12 ps. On a much longer time scale, hundreds of picoseconds, equilibrium heating of the nanofilm is reached, driving the system toward amorphization, provided that high excitation energy is invoked. These results elucidate the elementary steps defining the structural pathway in the transformation of crystalline-to-amorphous phase transitions and describe the essential atomic motions involved when driven by an ultrafast excitation. The establishment of the time scales of the different transient structures, as reported here, permits determination of the possible limit of performance, which is crucial for high-speed recording applications of PCMs.

  10. Development of AMS high resolution injector system

    International Nuclear Information System (INIS)

    Bao Yiwen; Guan Xialing; Hu Yueming

    2008-01-01

    The Beijing HI-13 tandem accelerator AMS high resolution injector system was developed. The high resolution energy achromatic system consists of an electrostatic analyzer and a magnetic analyzer, which mass resolution can reach 600 and transmission is better than 80%. (authors)

  11. Integrated High Resolution Monitoring of Mediterranean vegetation

    Science.gov (United States)

    Cesaraccio, Carla; Piga, Alessandra; Ventura, Andrea; Arca, Angelo; Duce, Pierpaolo; Mereu, Simone

    2017-04-01

    The study of the vegetation features in a complex and highly vulnerable ecosystems, such as Mediterranean maquis, leads to the need of using continuous monitoring systems at high spatial and temporal resolution, for a better interpretation of the mechanisms of phenological and eco-physiological processes. Near-surface remote sensing techniques are used to quantify, at high temporal resolution, and with a certain degree of spatial integration, the seasonal variations of the surface optical and radiometric properties. In recent decades, the design and implementation of global monitoring networks involved the use of non-destructive and/or cheaper approaches such as (i) continuous surface fluxes measurement stations, (ii) phenological observation networks, and (iii) measurement of temporal and spatial variations of the vegetation spectral properties. In this work preliminary results from the ECO-SCALE (Integrated High Resolution Monitoring of Mediterranean vegetation) project are reported. The project was manly aimed to develop an integrated system for environmental monitoring based on digital photography, hyperspectral radiometry , and micrometeorological techniques during three years of experimentation (2013-2016) in a Mediterranean site of Italy (Capo Caccia, Alghero). The main results concerned the analysis of chromatic coordinates indices from digital images, to characterized the phenological patterns for typical shrubland species, determining start and duration of the growing season, and the physiological status in relation to different environmental drought conditions; then the seasonal patterns of canopy phenology, was compared to NEE (Net Ecosystem Exchange) patterns, showing similarities. However, maximum values of NEE and ER (Ecosystem respiration), and short term variation, seemed mainly tuned by inter annual pattern of meteorological variables, in particular of temperature recorded in the months preceding the vegetation green-up. Finally, green signals

  12. The utility of the historical record for assessing the transient climate response to cumulative emissions

    Science.gov (United States)

    Friedlingstein, Pierre

    2018-01-01

    The historical observational record offers a way to constrain the relationship between cumulative carbon dioxide emissions and global mean warming. We use a standard detection and attribution technique, along with observational uncertainties to estimate the all-forcing or ‘effective’ transient climate response to cumulative emissions (TCRE) from the observational record. Accounting for observational uncertainty and uncertainty in historical non-CO2 radiative forcing gives a best-estimate from the historical record of 1.84°C/TtC (1.43–2.37°C/TtC 5–95% uncertainty) for the effective TCRE and 1.31°C/TtC (0.88–2.60°C/TtC 5–95% uncertainty) for the CO2-only TCRE. While the best-estimate TCRE lies in the lower half of the IPCC likely range, the high upper bound is associated with the not-ruled-out possibility of a strongly negative aerosol forcing. Earth System Models have a higher effective TCRE range when compared like-for-like with the observations over the historical period, associated in part with a slight underestimate of diagnosed cumulative emissions relative to the observational best-estimate, a larger ensemble mean-simulated CO2-induced warming, and rapid post-2000 non-CO2 warming in some ensemble members. This article is part of the theme issue ‘The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'. PMID:29610381

  13. The utility of the historical record for assessing the transient climate response to cumulative emissions

    Science.gov (United States)

    Millar, Richard J.; Friedlingstein, Pierre

    2018-05-01

    The historical observational record offers a way to constrain the relationship between cumulative carbon dioxide emissions and global mean warming. We use a standard detection and attribution technique, along with observational uncertainties to estimate the all-forcing or `effective' transient climate response to cumulative emissions (TCRE) from the observational record. Accounting for observational uncertainty and uncertainty in historical non-CO2 radiative forcing gives a best-estimate from the historical record of 1.84°C/TtC (1.43-2.37°C/TtC 5-95% uncertainty) for the effective TCRE and 1.31°C/TtC (0.88-2.60°C/TtC 5-95% uncertainty) for the CO2-only TCRE. While the best-estimate TCRE lies in the lower half of the IPCC likely range, the high upper bound is associated with the not-ruled-out possibility of a strongly negative aerosol forcing. Earth System Models have a higher effective TCRE range when compared like-for-like with the observations over the historical period, associated in part with a slight underestimate of diagnosed cumulative emissions relative to the observational best-estimate, a larger ensemble mean-simulated CO2-induced warming, and rapid post-2000 non-CO2 warming in some ensemble members. This article is part of the theme issue `The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'.

  14. High resolution sequence stratigraphy in China

    International Nuclear Information System (INIS)

    Zhang Shangfeng; Zhang Changmin; Yin Yanshi; Yin Taiju

    2008-01-01

    Since high resolution sequence stratigraphy was introduced into China by DENG Hong-wen in 1995, it has been experienced two development stages in China which are the beginning stage of theory research and development of theory research and application, and the stage of theoretical maturity and widely application that is going into. It is proved by practices that high resolution sequence stratigraphy plays more and more important roles in the exploration and development of oil and gas in Chinese continental oil-bearing basin and the research field spreads to the exploration of coal mine, uranium mine and other strata deposits. However, the theory of high resolution sequence stratigraphy still has some shortages, it should be improved in many aspects. The authors point out that high resolution sequence stratigraphy should be characterized quantitatively and modelized by computer techniques. (authors)

  15. High resolution CT of the chest

    Energy Technology Data Exchange (ETDEWEB)

    Barneveld Binkhuysen, F H [Eemland Hospital (Netherlands), Dept. of Radiology

    1996-12-31

    Compared to conventional CT high resolution CT (HRCT) shows several extra anatomical structures which might effect both diagnosis and therapy. The extra anatomical structures were discussed briefly in this article. (18 refs.).

  16. High-resolution spectrometer at PEP

    International Nuclear Information System (INIS)

    Weiss, J.M.; HRS Collaboration.

    1982-01-01

    A description is presented of the High Resolution Spectrometer experiment (PEP-12) now running at PEP. The advanced capabilities of the detector are demonstrated with first physics results expected in the coming months

  17. Structure of high-resolution NMR spectra

    CERN Document Server

    Corio, PL

    2012-01-01

    Structure of High-Resolution NMR Spectra provides the principles, theories, and mathematical and physical concepts of high-resolution nuclear magnetic resonance spectra.The book presents the elementary theory of magnetic resonance; the quantum mechanical theory of angular momentum; the general theory of steady state spectra; and multiple quantum transitions, double resonance and spin echo experiments.Physicists, chemists, and researchers will find the book a valuable reference text.

  18. Free radicals. High-resolution spectroscopy and molecular structure

    International Nuclear Information System (INIS)

    Hirota, E.

    1983-01-01

    High-resolution, high-sensitivity spectroscopy using CW laser and microwave sources has been applied to free radicals and transient molecules to establish their existence and to explore their properties in detail. The radicals studied were mainly generated by discharge-induced reactions. A few molecules are used as typical examples to illustrate the results so far obtained. The molecular and electronic structures of free radicals, intramolecular motions of large amplitudes in some labile molecules, and metastable electronic states of carbenes are given special emphasis. The significance of the present spectroscopic results in other related fields such as astronomy and atmospheric chemistry is stressed. 4 figures, 3 tables

  19. Readout of delayline detectors with transient recorders; Auslese von Delaylinedetektoren mit Hilfe von Transientenrekordern

    Energy Technology Data Exchange (ETDEWEB)

    Foucar, Lutz Michael

    2008-09-18

    The task of the presented work consists in the development of software to operate the transient recorders under the conditions of a real experiment. Another task was to find a proper method of analyzing the recorded signals. Several methods were tested with simulated and real detector signals. In the first chapter the motivation to this work and some theoretical background are presented. In the second chapter methods to analyze single pulses and trains of overlapping pulses are presented. The quality of the presented algorithms is determined by signals created artificially in software. It is shown that the best temporal resolution - for case of non-overlapping pulses - is obtained with a pulse fit. With this method a resolution of approximately 50 ps is achieved. In order to disentangling overlapping pulses a minimum distance in time between the pulses of at least 5 ns to 7 ns peak to peak is necessary. The third chapter shows an application of the new recording system where results of the new recording method are compared to those obtained with the traditional method. The next chapter presents another experiment in which an even larger amount of fragments had to be detected. In order to cope with this requirement further criteria to assign the measured signal to its originating particle is presented. In this chapter results from photo ionization of helium and neon are shown. The next chapter consist of another application of the methods developed in this work on a real experiment: the reaction examined leads in many cases to two particles that need to be detected within a time of only 30 ns. It turns out that the dead time for real signals is comparable to that of simulated signals. The algorithms cannot accurately determine the timing of two signals that are separated in time by less than 10 ns. On the basis of the pulse height distribution it can be shown that the used detector had smaller efficiency at its center. In the last chapter the quality of the

  20. High-resolution phylogenetic microbial community profiling

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Esther; Coleman-Derr, Devin; Bowman, Brett; Schwientek, Patrick; Clum, Alicia; Copeland, Alex; Ciobanu, Doina; Cheng, Jan-Fang; Gies, Esther; Hallam, Steve; Tringe, Susannah; Woyke, Tanja

    2014-03-17

    The representation of bacterial and archaeal genome sequences is strongly biased towards cultivated organisms, which belong to merely four phylogenetic groups. Functional information and inter-phylum level relationships are still largely underexplored for candidate phyla, which are often referred to as microbial dark matter. Furthermore, a large portion of the 16S rRNA gene records in the GenBank database are labeled as environmental samples and unclassified, which is in part due to low read accuracy, potential chimeric sequences produced during PCR amplifications and the low resolution of short amplicons. In order to improve the phylogenetic classification of novel species and advance our knowledge of the ecosystem function of uncultivated microorganisms, high-throughput full length 16S rRNA gene sequencing methodologies with reduced biases are needed. We evaluated the performance of PacBio single-molecule real-time (SMRT) sequencing in high-resolution phylogenetic microbial community profiling. For this purpose, we compared PacBio and Illumina metagenomic shotgun and 16S rRNA gene sequencing of a mock community as well as of an environmental sample from Sakinaw Lake, British Columbia. Sakinaw Lake is known to contain a large age of microbial species from candidate phyla. Sequencing results show that community structure based on PacBio shotgun and 16S rRNA gene sequences is highly similar in both the mock and the environmental communities. Resolution power and community representation accuracy from SMRT sequencing data appeared to be independent of GC content of microbial genomes and was higher when compared to Illumina-based metagenome shotgun and 16S rRNA gene (iTag) sequences, e.g. full-length sequencing resolved all 23 OTUs in the mock community, while iTags did not resolve closely related species. SMRT sequencing hence offers various potential benefits when characterizing uncharted microbial communities.

  1. High-resolution observation by double-biprism electron holography

    International Nuclear Information System (INIS)

    Harada, Ken; Tonomura, Akira; Matsuda, Tsuyoshi; Akashi, Tetsuya; Togawa, Yoshihiko

    2004-01-01

    High-resolution electron holography has been achieved by using a double-biprism interferometer implemented on a 1 MV field emission electron microscope. The interferometer was installed behind the first magnifying lens to narrow carrier fringes and thus enabled complete separation of sideband Fourier spectrum from center band in reconstruction process. Holograms of Au fine particles and single-crystalline thin films with the finest fringe spacing of 4.2 pm were recorded and reconstructed. The overall holography system including the reconstruction process performed well for holograms in which carrier fringes had a spacing of around 10 pm. High-resolution lattice images of the amplitude and phase were clearly reconstructed without mixing of the center band and sideband information. Additionally, entire holograms were recorded without Fresnel fringes normally generated by the filament electrode of the biprism, and the holograms were thus reconstructed without the artifacts caused by Fresnel fringes

  2. The physical hydrology of magmatic-hydrothermal systems: High-resolution 18O records of magmatic-meteoric water interaction from the Yankee Lode tin deposit (Mole Granite, Australia)

    Science.gov (United States)

    Fekete, Szandra; Weis, Philipp; Driesner, Thomas; Heinrich, Christoph A.; Baumgartner, Lukas; Bouvier, Anne-Sophie

    2016-04-01

    Magmatic-hydrothermal ore deposits are important economic Cu, Au, Mo and Sn resources (Sillitoe, 2010, Kesler, 1994). The ore formation is a result of superimposed enrichment processes and metals can precipitate due to fluid-rock interaction and/or temperature drop caused by convection or mixing with meteoric fluid (Heinrich and Candela 2014). Microthermometry and LA-ICP MS trace element analyses of fluid inclusions of a well-characterized quartz sample from the Yankee Lode quartz-cassiterite vein deposit (Mole Granite, Australia) suggest that tin precipitation was driven by dilution of hot magmatic water by meteoric fluids (Audétat et al.1998). High resolution in situ oxygen isotope measurements of quartz have the potential to detect changing fluid sources during the evolution of a hydrothermal system. We analyzed the euhedral growth zones of this previously well-studied quartz sample. Growth temperatures are provided by Audétat et al. (1998) and Audétat (1999). Calculated δ 18O values of the quartz- and/or cassiterite-precipitating fluid show significant variability through the zoned crystal. The first and second quartz generations (Q1 and Q2) were precipitated from a fluid of magmatic isotopic composition with δ 18O values of ˜ 8 - 10 ‰. δ 18O values of Q3- and tourmaline-precipitating fluids show a transition from magmatic δ 18O values of ˜ 8 ‰ to ˜ -5 ‰. The outermost quartz-chlorite-muscovite zone was precipitated from a fluid with a significant meteoric water component reflected by very light δ 18O values of about -15 ‰ which is consistent with values found by previous studies (Sun and Eadington, 1987) using conventional O-isotope analysis of veins in the distal halo of the granite intrusion. Intense incursion of meteoric water during Q3 precipitation (light δ 18O values) agrees with the main ore formation event, though the first occurrence of cassiterite is linked to Q2 precipitating fluid with magmatic-like isotope signature. This

  3. High resolution atomic spectra of rare earths : progress report

    International Nuclear Information System (INIS)

    Saksena, G.D.; Ahmad, S.A.

    1976-01-01

    High resolution studies of atomic spectra of neodymium and gadolinium are being carried out on a recording Fabry-Perot spectrometer. The present progress report concerns work done on new assignments as well as confirmation of recently assigned electronic configurations and evaluation of isotope shifts of energy levels which have been possible from the isotope shift data obtained for several transitions of NdI, NdII and GdI, GdII respectively. (author)

  4. Progress in high-resolution x-ray holographic microscopy

    International Nuclear Information System (INIS)

    Jacobsen, C.; Kirz, J.; Howells, M.; McQuaid, K.; Rothman, S.; Feder, R.; Sayre, D.

    1987-07-01

    Among the various types of x-ray microscopes that have been demonstrated, the holographic microscope has had the largest gap between promise and performance. The difficulties of fabricating x-ray optical elements have led some to view holography as the most attractive method for obtaining the ultimate in high resolution x-ray micrographs; however, we know of no investigations prior to 1987 that clearly demonstrated submicron resolution in reconstructed images. Previous efforts suffered from problems such as limited resolution and dynamic range in the recording media, low coherent x-ray flux, and aberrations and diffraction limits in visible light reconstruction. We have addressed the recording limitations through the use of an undulator x-ray source and high-resolution photoresist recording media. For improved results in the readout and reconstruction steps, we have employed metal shadowing and transmission electron microscopy, along with numerical reconstruction techniques. We believe that this approach will allow holography to emerge as a practical method of high-resolution x-ray microscopy. 30 refs., 4 figs

  5. Progress in high-resolution x-ray holographic microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Jacobsen, C.; Kirz, J.; Howells, M.; McQuaid, K.; Rothman, S.; Feder, R.; Sayre, D.

    1987-07-01

    Among the various types of x-ray microscopes that have been demonstrated, the holographic microscope has had the largest gap between promise and performance. The difficulties of fabricating x-ray optical elements have led some to view holography as the most attractive method for obtaining the ultimate in high resolution x-ray micrographs; however, we know of no investigations prior to 1987 that clearly demonstrated submicron resolution in reconstructed images. Previous efforts suffered from problems such as limited resolution and dynamic range in the recording media, low coherent x-ray flux, and aberrations and diffraction limits in visible light reconstruction. We have addressed the recording limitations through the use of an undulator x-ray source and high-resolution photoresist recording media. For improved results in the readout and reconstruction steps, we have employed metal shadowing and transmission electron microscopy, along with numerical reconstruction techniques. We believe that this approach will allow holography to emerge as a practical method of high-resolution x-ray microscopy. 30 refs., 4 figs.

  6. A high resolution portable spectroscopy system

    International Nuclear Information System (INIS)

    Kulkarni, C.P.; Vaidya, P.P.; Paulson, M.; Bhatnagar, P.V.; Pande, S.S.; Padmini, S.

    2003-01-01

    Full text: This paper describes the system details of a High Resolution Portable Spectroscopy System (HRPSS) developed at Electronics Division, BARC. The system can be used for laboratory class, high-resolution nuclear spectroscopy applications. The HRPSS consists of a specially designed compact NIM bin, with built-in power supplies, accommodating a low power, high resolution MCA, and on-board embedded computer for spectrum building and communication. A NIM based spectroscopy amplifier and a HV module for detector bias are integrated (plug-in) in the bin. The system communicates with a host PC via a serial link. Along-with a laptop PC, and a portable HP-Ge detector, the HRPSS offers a laboratory class performance for portable applications

  7. A continuous high-resolution record of western South Island environmental change over the last 31,000 years from stable isotope analyses of two north-west Nelson speleothems

    International Nuclear Information System (INIS)

    Hellstrom, J.; McCulloch, M.; Stone, J.

    1997-01-01

    Core samples were taken through large sheets of calcite flowstone growing in two cave systems, Nettlebed, and Exhaleair, in north-west Nelson, New Zealand. The sampled flowstones are at elevations of 400 m asl and 600 m asl, and are both located 200m below the surface. Ten high-precision U-series dates, measured by thermal ionisation mass spectroemtry, indicate the Nettlebed flowstone grew continuously over the last 31 ka. The Exhaleair flowstone grew continuously over the last 16 ka, following a 50 ka hiatus in deposition. The speleothems from both caves show similar records of oxygen isotope variation over the last 16 ka. The carbon isotope record from Nettlebed shows considerable variation, of almost 10 per thousand from the last glacial maximum to the early Holocene. It is anticipated that these well-dated speleothem records will enable more accurate constraints to be placed on the timing of glacial advances and vegetation changes in the western South Island than are possible using the available radiocarbon ages alone. (author)

  8. High-resolution multi-slice PET

    International Nuclear Information System (INIS)

    Yasillo, N.J.; Chintu Chen; Ordonez, C.E.; Kapp, O.H.; Sosnowski, J.; Beck, R.N.

    1992-01-01

    This report evaluates the progress to test the feasibility and to initiate the design of a high resolution multi-slice PET system. The following specific areas were evaluated: detector development and testing; electronics configuration and design; mechanical design; and system simulation. The design and construction of a multiple-slice, high-resolution positron tomograph will provide substantial improvements in the accuracy and reproducibility of measurements of the distribution of activity concentrations in the brain. The range of functional brain research and our understanding of local brain function will be greatly extended when the development of this instrumentation is completed

  9. High resolution Neutron and Synchrotron Powder Diffraction

    International Nuclear Information System (INIS)

    Hewat, A.W.

    1986-01-01

    The use of high-resolution powder diffraction has grown rapidly in the past years, with the development of Rietveld (1967) methods of data analysis and new high-resolution diffractometers and multidetectors. The number of publications in this area has increased from a handful per year until 1973 to 150 per year in 1984, with a ten-year total of over 1000. These papers cover a wide area of solid state-chemistry, physics and materials science, and have been grouped under 20 subject headings, ranging from catalysts to zeolites, and from battery electrode materials to pre-stressed superconducting wires. In 1985 two new high-resolution diffractometers are being commissioned, one at the SNS laboratory near Oxford, and one at the ILL in Grenoble. In different ways these machines represent perhaps the ultimate that can be achieved with neutrons and will permit refinement of complex structures with about 250 parameters and unit cell volumes of about 2500 Angstrom/sp3/. The new European Synchotron Facility will complement the Grenoble neutron diffractometers, and extend the role of high-resolution powder diffraction to the direct solution of crystal structures, pioneered in Sweden

  10. High resolution CT in diffuse lung disease

    International Nuclear Information System (INIS)

    Webb, W.R.

    1995-01-01

    High resolution CT (computerized tomography) was discussed in detail. The conclusions were HRCT is able to define lung anatomy at the secondary lobular level and define a variety of abnormalities in patients with diffuse lung diseases. Evidence from numerous studies indicates that HRCT can play a major role in the assessment of diffuse infiltrative lung disease and is indicate clinically (95 refs.)

  11. Classification of high resolution satellite images

    OpenAIRE

    Karlsson, Anders

    2003-01-01

    In this thesis the Support Vector Machine (SVM)is applied on classification of high resolution satellite images. Sveral different measures for classification, including texture mesasures, 1st order statistics, and simple contextual information were evaluated. Additionnally, the image was segmented, using an enhanced watershed method, in order to improve the classification accuracy.

  12. High resolution CT in diffuse lung disease

    Energy Technology Data Exchange (ETDEWEB)

    Webb, W R [California Univ., San Francisco, CA (United States). Dept. of Radiology

    1996-12-31

    High resolution CT (computerized tomography) was discussed in detail. The conclusions were HRCT is able to define lung anatomy at the secondary lobular level and define a variety of abnormalities in patients with diffuse lung diseases. Evidence from numerous studies indicates that HRCT can play a major role in the assessment of diffuse infiltrative lung disease and is indicate clinically (95 refs.).

  13. High-resolution clean-sc

    NARCIS (Netherlands)

    Sijtsma, P.; Snellen, M.

    2016-01-01

    In this paper a high-resolution extension of CLEAN-SC is proposed: HR-CLEAN-SC. Where CLEAN-SC uses peak sources in “dirty maps” to define so-called source components, HR-CLEAN-SC takes advantage of the fact that source components can likewise be derived from points at some distance from the peak,

  14. A High-Resolution Stopwatch for Cents

    Science.gov (United States)

    Gingl, Z.; Kopasz, K.

    2011-01-01

    A very low-cost, easy-to-make stopwatch is presented to support various experiments in mechanics. The high-resolution stopwatch is based on two photodetectors connected directly to the microphone input of a sound card. Dedicated free open-source software has been developed and made available to download. The efficiency is demonstrated by a free…

  15. Planning for shallow high resolution seismic surveys

    CSIR Research Space (South Africa)

    Fourie, CJS

    2008-11-01

    Full Text Available of the input wave. This information can be used in conjunction with this spreadsheet to aid the geophysicist in designing shallow high resolution seismic surveys to achieve maximum resolution and penetration. This Excel spreadsheet is available free from...

  16. The high resolution shear wave seismic reflection technique

    International Nuclear Information System (INIS)

    Johnson, W.J.; Clark, J.C.

    1991-04-01

    This report presents the state-of-the-art of the high resolution S-wave reflection technique. Published and unpublished literature has been reviewed and discussions have been held with experts. Result is to confirm that the proposed theoretical and practical basis for identifying aquifer systems using both P- and S-wave reflections is sound. Knowledge of S-wave velocity and P-wave velocity is a powerful tool for assessing the fluid characteristics of subsurface layers. Material properties and lateral changes in material properties such as change from clay to sand, can be inferred from careful dual evaluation of P and S-wave records. The high resolution S-wave reflection technique has seen its greatest application to date as part of geotechnical studies for building foundations in the Far East. Information from this type of study has been evaluated and will be incorporated in field studies. In particular, useful information regarding S-wave sources, noise suppression and recording procedures will be incorporated within the field studies. Case histories indicate that the best type of site for demonstrating the power of the high resolution S-wave technique will be in unconsolidated soil without excessive structural complexities. More complex sites can form the basis for subsequent research after the basic principles of the technique can be established under relatively uncomplicated conditions

  17. Clickstream data yields high-resolution maps of science

    Energy Technology Data Exchange (ETDEWEB)

    Bollen, Johan [Los Alamos National Laboratory; Van De Sompel, Herbert [Los Alamos National Laboratory; Hagberg, Aric [Los Alamos National Laboratory; Bettencourt, Luis [Los Alamos National Laboratory; Chute, Ryan [Los Alamos National Laboratory; Rodriguez, Marko A [Los Alamos National Laboratory; Balakireva, Lyudmila [Los Alamos National Laboratory

    2009-01-01

    Intricate maps of science have been created from citation data to visualize the structure of scientific activity. However, most scientific publications are now accessed online. Scholarly web portals record detailed log data at a scale that exceeds the number of all existing citations combined. Such log data is recorded immediately upon publication and keeps track of the sequences of user requests (clickstreams) that are issued by a variety of users across many different domains. Given these advantagees of log datasets over citation data, we investigate whether they can produce high-resolution, more current maps of science.

  18. Smartphone microendoscopy for high resolution fluorescence imaging

    Directory of Open Access Journals (Sweden)

    Xiangqian Hong

    2016-09-01

    Full Text Available High resolution optical endoscopes are increasingly used in diagnosis of various medical conditions of internal organs, such as the cervix and gastrointestinal (GI tracts, but they are too expensive for use in resource-poor settings. On the other hand, smartphones with high resolution cameras and Internet access have become more affordable, enabling them to diffuse into most rural areas and developing countries in the past decade. In this paper, we describe a smartphone microendoscope that can take fluorescence images with a spatial resolution of 3.1 μm. Images collected from ex vivo, in vitro and in vivo samples using the device are also presented. The compact and cost-effective smartphone microendoscope may be envisaged as a powerful tool for detecting pre-cancerous lesions of internal organs in low and middle-income countries (LMICs.

  19. High resolution NMR theory and chemical applications

    CERN Document Server

    Becker, Edwin D

    2012-01-01

    High Resolution NMR: Theory and Chemical Applications discusses the principles and theory of nuclear magnetic resonance and how this concept is used in the chemical sciences. This book is written at an intermediate level, with mathematics used to augment verbal descriptions of the phenomena. This text pays attention to developing and interrelating four approaches - the steady state energy levels, the rotating vector picture, the density matrix, and the product operator formalism. The style of this book is based on the assumption that the reader has an acquaintance with the general principles of quantum mechanics, but no extensive background in quantum theory or proficiency in mathematics is required. This book begins with a description of the basic physics, together with a brief account of the historical development of the field. It looks at the study of NMR in liquids, including high resolution NMR in the solid state and the principles of NMR imaging and localized spectroscopy. This book is intended to assis...

  20. High resolution NMR theory and chemical applications

    CERN Document Server

    Becker, Edwin D

    1999-01-01

    High Resolution NMR provides a broad treatment of the principles and theory of nuclear magnetic resonance (NMR) as it is used in the chemical sciences. It is written at an "intermediate" level, with mathematics used to augment, rather than replace, clear verbal descriptions of the phenomena. The book is intended to allow a graduate student, advanced undergraduate, or researcher to understand NMR at a fundamental level, and to see illustrations of the applications of NMR to the determination of the structure of small organic molecules and macromolecules, including proteins. Emphasis is on the study of NMR in liquids, but the treatment also includes high resolution NMR in the solid state and the principles of NMR imaging and localized spectroscopy. Careful attention is given to developing and interrelating four approaches - steady state energy levels, the rotating vector picture, the density matrix, and the product operator formalism. The presentation is based on the assumption that the reader has an acquaintan...

  1. Automatic classification of transient ischaemic and transient non-ischaemic heart-rate related ST segment deviation episodes in ambulatory ECG records

    International Nuclear Information System (INIS)

    Faganeli, J; Jager, F

    2010-01-01

    In ambulatory ECG records, besides transient ischaemic ST segment deviation episodes, there are also transient non-ischaemic heart-rate related ST segment deviation episodes present, which appear only due to a change in heart rate and thus complicate automatic detection of true ischaemic episodes. The goal of this work was to automatically classify these two types of episodes. The tested features to classify the ST segment deviation episodes were changes of heart rate, changes of the Mahalanobis distance of the first five Karhunen–Loève transform (KLT) coefficients of the QRS complex, changes of time-domain morphologic parameters of the ST segment and changes of the Legendre orthonormal polynomial coefficients of the ST segment. We chose Legendre basis functions because they best fit typical shapes of the ST segment morphology, thus allowing direct insight into the ST segment morphology changes through the feature space. The classification was performed with the help of decision trees. We tested the classification method using all records of the Long-Term ST Database on all ischaemic and all non-ischaemic heart-rate related deviation episodes according to annotation protocol B. In order to predict the real-world performance of the classification we used second-order aggregate statistics, gross and average statistics, and the bootstrap method. We obtained the best performance when we combined the heart-rate features, the Mahalanobis distance and the Legendre orthonormal polynomial coefficient features, with average sensitivity of 98.1% and average specificity of 85.2%

  2. High resolution imaging of boron carbide microstructures

    International Nuclear Information System (INIS)

    MacKinnon, I.D.R.; Aselage, T.; Van Deusen, S.B.

    1986-01-01

    Two samples of boron carbide have been examined using high resolution transmission electron microscopy (HRTEM). A hot-pressed B 13 C 2 sample shows a high density of variable width twins normal to (10*1). Subtle shifts or offsets of lattice fringes along the twin plane and normal to approx.(10*5) were also observed. A B 4 C powder showed little evidence of stacking disorder in crystalline regions

  3. High-Resolution MRI in Rectal Cancer

    International Nuclear Information System (INIS)

    Dieguez, Adriana

    2010-01-01

    High-resolution MRI is the best method of assessing the relation of the rectal tumor with the potential circumferential resection margin (CRM). Therefore it is currently considered the method of choice for local staging of rectal cancer. The primary surgery of rectal cancer is total mesorectal excision (TME), which plane of dissection is formed by the mesorectal fascia surrounding mesorectal fat and rectum. This fascia will determine the circumferential margin of resection. At the same time, high resolution MRI allows adequate pre-operative identification of important prognostic risk factors, improving the selection and indication of therapy for each patient. This information includes, besides the circumferential margin of resection, tumor and lymph node staging, extramural vascular invasion and the description of lower rectal tumors. All these should be described in detail in the report, being part of the discussion in the multidisciplinary team, the place where the decisions involving the patient with rectal cancer will take place. The aim of this study is to provide the information necessary to understand the use of high resolution MRI in the identification of prognostic risk factors in rectal cancer. The technical requirements and standardized report for this study will be describe, as well as the anatomical landmarks of importance for the total mesorectal excision (TME), as we have said is the surgery of choice for rectal cancer. (authors) [es

  4. Ultra-high resolution protein crystallography

    International Nuclear Information System (INIS)

    Takeda, Kazuki; Hirano, Yu; Miki, Kunio

    2010-01-01

    Many protein structures have been determined by X-ray crystallography and deposited with the Protein Data Bank. However, these structures at usual resolution (1.5< d<3.0 A) are insufficient in their precision and quantity for elucidating the molecular mechanism of protein functions directly from structural information. Several studies at ultra-high resolution (d<0.8 A) have been performed with synchrotron radiation in the last decade. The highest resolution of the protein crystals was achieved at 0.54 A resolution for a small protein, crambin. In such high resolution crystals, almost all of hydrogen atoms of proteins and some hydrogen atoms of bound water molecules are experimentally observed. In addition, outer-shell electrons of proteins can be analyzed by the multipole refinement procedure. However, the influence of X-rays should be precisely estimated in order to derive meaningful information from the crystallographic results. In this review, we summarize refinement procedures, current status and perspectives for ultra high resolution protein crystallography. (author)

  5. The demonstration of the auditory ossicles by high resolution CT

    International Nuclear Information System (INIS)

    Lloyd, G.A.S.; Boulay, G.H. du; Phelps, P.D.; Pullicino, P.

    1979-01-01

    The high resolution CT scanning system introduced by EMI in 1978 has added a new dimension to computerised tomography in otology. The apparatus used for this study was an EMI CT 5005 body scanner adapted for head and neck scanning and incorporating a high resolution facility. The latter has proved most advantageous in areas of relatively high differential absorption, so that its application to the demonstration of abnormalities in the petrous temporal bone, and in particular middle ear disease, has been very rewarding. Traumatic ossicular disruptions may now be demonstrated and the high contrast of CT often shows them better than conventional hypocycloidal tomography. The stapes is also better visualised and congenital abnormalities of its superstructure have been recorded. These studies have been achieved with a very acceptable level of radiation to the eye, lens and cornea and the technique is clearly a rival to conventional pluridirectional tomography in the assessment of the petrous temporal bone. With further design improvements high resolution CT could completely replace existing techniques. (orig.) [de

  6. High resolution, high speed ultrahigh vacuum microscopy

    International Nuclear Information System (INIS)

    Poppa, Helmut

    2004-01-01

    The history and future of transmission electron microscopy (TEM) is discussed as it refers to the eventual development of instruments and techniques applicable to the real time in situ investigation of surface processes with high resolution. To reach this objective, it was necessary to transform conventional high resolution instruments so that an ultrahigh vacuum (UHV) environment at the sample site was created, that access to the sample by various in situ sample modification procedures was provided, and that in situ sample exchanges with other integrated surface analytical systems became possible. Furthermore, high resolution image acquisition systems had to be developed to take advantage of the high speed imaging capabilities of projection imaging microscopes. These changes to conventional electron microscopy and its uses were slowly realized in a few international laboratories over a period of almost 40 years by a relatively small number of researchers crucially interested in advancing the state of the art of electron microscopy and its applications to diverse areas of interest; often concentrating on the nucleation, growth, and properties of thin films on well defined material surfaces. A part of this review is dedicated to the recognition of the major contributions to surface and thin film science by these pioneers. Finally, some of the important current developments in aberration corrected electron optics and eventual adaptations to in situ UHV microscopy are discussed. As a result of all the path breaking developments that have led to today's highly sophisticated UHV-TEM systems, integrated fundamental studies are now possible that combine many traditional surface science approaches. Combined investigations to date have involved in situ and ex situ surface microscopies such as scanning tunneling microscopy/atomic force microscopy, scanning Auger microscopy, and photoemission electron microscopy, and area-integrating techniques such as x-ray photoelectron

  7. USGS High Resolution Orthoimagery Collection - Historical - National Geospatial Data Asset (NGDA) High Resolution Orthoimagery

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — USGS high resolution orthorectified images from The National Map combine the image characteristics of an aerial photograph with the geometric qualities of a map. An...

  8. High-resolution x-ray photoemission spectra of silver

    DEFF Research Database (Denmark)

    Barrie, A.; Christensen, N. E.

    1976-01-01

    An electron spectrometer fitted with an x-ray monochromator for Al Kα1,2 radiation (1486.6 eV) has been used to record high-resolution x-ray photoelectron spectra for the 4d valence band as well as the 3d spin doublet in silver. The core-level spectrum has a line shape that can be described...... successfully in terms of the many-body theory of Mahan, Nozières, and De Dominicis. The 4d spectrum agrees well with predictions based on a relativistic-augmented-plane-wave band-structure calculation....

  9. High resolution extremity CT for biomechanics modeling

    International Nuclear Information System (INIS)

    Ashby, A.E.; Brand, H.; Hollerbach, K.; Logan, C.M.; Martz, H.E.

    1995-01-01

    With the advent of ever more powerful computing and finite element analysis (FEA) capabilities, the bone and joint geometry detail available from either commercial surface definitions or from medical CT scans is inadequate. For dynamic FEA modeling of joints, precise articular contours are necessary to get appropriate contact definition. In this project, a fresh cadaver extremity was suspended in parafin in a lucite cylinder and then scanned with an industrial CT system to generate a high resolution data set for use in biomechanics modeling

  10. Ultra-high resolution coded wavefront sensor

    KAUST Repository

    Wang, Congli

    2017-06-08

    Wavefront sensors and more general phase retrieval methods have recently attracted a lot of attention in a host of application domains, ranging from astronomy to scientific imaging and microscopy. In this paper, we introduce a new class of sensor, the Coded Wavefront Sensor, which provides high spatio-temporal resolution using a simple masked sensor under white light illumination. Specifically, we demonstrate megapixel spatial resolution and phase accuracy better than 0.1 wavelengths at reconstruction rates of 50 Hz or more, thus opening up many new applications from high-resolution adaptive optics to real-time phase retrieval in microscopy.

  11. High resolution extremity CT for biomechanics modeling

    Energy Technology Data Exchange (ETDEWEB)

    Ashby, A.E.; Brand, H.; Hollerbach, K.; Logan, C.M.; Martz, H.E.

    1995-09-23

    With the advent of ever more powerful computing and finite element analysis (FEA) capabilities, the bone and joint geometry detail available from either commercial surface definitions or from medical CT scans is inadequate. For dynamic FEA modeling of joints, precise articular contours are necessary to get appropriate contact definition. In this project, a fresh cadaver extremity was suspended in parafin in a lucite cylinder and then scanned with an industrial CT system to generate a high resolution data set for use in biomechanics modeling.

  12. High-resolution computer-aided moire

    Science.gov (United States)

    Sciammarella, Cesar A.; Bhat, Gopalakrishna K.

    1991-12-01

    This paper presents a high resolution computer assisted moire technique for the measurement of displacements and strains at the microscopic level. The detection of micro-displacements using a moire grid and the problem associated with the recovery of displacement field from the sampled values of the grid intensity are discussed. A two dimensional Fourier transform method for the extraction of displacements from the image of the moire grid is outlined. An example of application of the technique to the measurement of strains and stresses in the vicinity of the crack tip in a compact tension specimen is given.

  13. SPIRAL2/DESIR high resolution mass separator

    Energy Technology Data Exchange (ETDEWEB)

    Kurtukian-Nieto, T., E-mail: kurtukia@cenbg.in2p3.fr [Centre d’Études Nucléaires de Bordeaux Gradignan, Université Bordeaux 1-CNRS/IN2P3, BP 120, F-33175 Gradignan Cedex (France); Baartman, R. [TRIUMF, 4004 Wesbrook Mall, Vancouver B.C., V6T 2A3 (Canada); Blank, B.; Chiron, T. [Centre d’Études Nucléaires de Bordeaux Gradignan, Université Bordeaux 1-CNRS/IN2P3, BP 120, F-33175 Gradignan Cedex (France); Davids, C. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Delalee, F. [Centre d’Études Nucléaires de Bordeaux Gradignan, Université Bordeaux 1-CNRS/IN2P3, BP 120, F-33175 Gradignan Cedex (France); Duval, M. [GANIL, CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5 (France); El Abbeir, S.; Fournier, A. [Centre d’Études Nucléaires de Bordeaux Gradignan, Université Bordeaux 1-CNRS/IN2P3, BP 120, F-33175 Gradignan Cedex (France); Lunney, D. [CSNSM-IN2P3-CNRS, Université de Paris Sud, F-91405 Orsay (France); Méot, F. [BNL, Upton, Long Island, New York (United States); Serani, L. [Centre d’Études Nucléaires de Bordeaux Gradignan, Université Bordeaux 1-CNRS/IN2P3, BP 120, F-33175 Gradignan Cedex (France); Stodel, M.-H.; Varenne, F. [GANIL, CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5 (France); and others

    2013-12-15

    DESIR is the low-energy part of the SPIRAL2 ISOL facility under construction at GANIL. DESIR includes a high-resolution mass separator (HRS) with a designed resolving power m/Δm of 31,000 for a 1 π-mm-mrad beam emittance, obtained using a high-intensity beam cooling device. The proposed design consists of two 90-degree magnetic dipoles, complemented by electrostatic quadrupoles, sextupoles, and a multipole, arranged in a symmetric configuration to minimize aberrations. A detailed description of the design and results of extensive simulations are given.

  14. Laboratory of High resolution gamma spectrometry

    International Nuclear Information System (INIS)

    Mendez G, A.; Giber F, J.; Rivas C, I.; Reyes A, B.

    1992-01-01

    The Department of Nuclear Experimentation of the Nuclear Systems Management requests the collaboration of the Engineering unit for the supervision of the execution of the work of the High resolution Gamma spectrometry and low bottom laboratory, using the hut of the sub critic reactor of the Nuclear Center of Mexico. This laboratory has the purpose of determining the activity of special materials irradiated in nuclear power plants. In this report the architecture development, concepts, materials and diagrams for the realization of this type of work are presented. (Author)

  15. High resolution neutron spectroscopy for helium isotopes

    International Nuclear Information System (INIS)

    Abdel-Wahab, M.S.; Klages, H.O.; Schmalz, G.; Haesner, B.H.; Kecskemeti, J.; Schwarz, P.; Wilczynski, J.

    1992-01-01

    A high resolution fast neutron time-of-flight spectrometer is described, neutron time-of-flight spectra are taken using a specially designed TDC in connection to an on-line computer. The high time-of-flight resolution of 5 ps/m enabled the study of the total cross section of 4 He for neutrons near the 3/2 + resonance in the 5 He nucleus. The resonance parameters were determined by a single level Breit-Winger fit to the data. (orig.)

  16. Atrial fibrillation detected by external loop recording for seven days or two-day simultaneous Holter recording: A comparison in patients with ischemic stroke or transient ischemic attack.

    Science.gov (United States)

    Sejr, Michala Herskind; Nielsen, Jens Cosedis; Damgaard, Dorte; Sandal, Birgitte Forsom; May, Ole

    Atrial fibrillation (AF) is the most common cardiac cause of ischemic stroke and transient ischemic attack (IS/TIA). To compare the diagnostic value of seven-day external loop recording (ELR) and two-day Holter recording for detecting AF after IS/TIA. 191 IS/TIA patients without AF history. Endpoint was AF >30s. We started two-day Holter recording and seven-day ELR simultaneously. Seven-day ELR and two-day Holter recording detected the same three AF patients. ELR detected another six patients with AF adjudicated by cardiologists, four detections after Holter (3 vs. 7, p=0.125) and two false-positive detections during Holter. Seven-day ELR automatically classified 50/191 patients (26%) with AF, but only 7/50 (14%) were confirmed as AF by cardiologists. Seven-day ELR did not detect significantly more patients with AF than two-day Holter recording. 86% of patients with ELR-classified AF were false positives, indicating a poor performance of the automatic AF detection algorithm used. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. High Resolution Thz and FIR Spectroscopy of SOCl_2

    Science.gov (United States)

    Martin-Drumel, M. A.; Cuisset, A.; Sadovskii, D. A.; Mouret, G.; Hindle, F.; Pirali, O.

    2013-06-01

    Thionyl chloride (SOCl_2) is an extremely powerful oxidant widely used in industrial processes and playing a role in the chemistry of the atmosphere. In addition, it has a molecular configuration similar to that of phosgene (COCl_2), and is therefore of particular interest for security and defense applications. Low resolution vibrational spectra of gas phase SOCl_2 as well as high resolution pure rotational transitions up to 25 GHz have previously been investigated. To date no high resolution data are reported at frequencies higher than 25 GHz. We have investigated the THz absorption spectrum of SOCl_2 in the spectral region 70-650 GHz using a frequency multiplier chain coupled to a 1 m long single path cell containing a pressure of about 15 μbar. At the time of the writing, about 8000 pure rotational transitions of SO^{35}Cl_2 with highest J and K_a values of 110 and 50 respectively have been assigned on the spectrum. We have also recorded the high resolution FIR spectra of SOCl_2 in the spectral range 50-700 wn using synchrotron radiation at the AILES beamline of SOLEIL facility. A White-type cell aligned with an absorption path length of 150 m has been used to record, at a resolution of 0.001 wn, two spectra at pressures of 5 and 56 μbar of SOCl_2. On these spectra all FIR modes of SOCl_2 are observed (ν_2 to ν_6) and present a resolved rotational structure. Their analysis is in progress. T. J. Johnson et al., J. Phys. Chem. A 107, 6183 (2003) D. E. Martz and R. T. Lagemann, J. Chem. Phys. 22,1193 (1954) H. S. P. Müller and M. C. L. Gerry, J. Chem. Soc. Faraday Trans. 90, 3473 (1994)

  18. Limiting liability via high resolution image processing

    Energy Technology Data Exchange (ETDEWEB)

    Greenwade, L.E.; Overlin, T.K.

    1996-12-31

    The utilization of high resolution image processing allows forensic analysts and visualization scientists to assist detectives by enhancing field photographs, and by providing the tools and training to increase the quality and usability of field photos. Through the use of digitized photographs and computerized enhancement software, field evidence can be obtained and processed as `evidence ready`, even in poor lighting and shadowed conditions or darkened rooms. These images, which are most often unusable when taken with standard camera equipment, can be shot in the worst of photographic condition and be processed as usable evidence. Visualization scientists have taken the use of digital photographic image processing and moved the process of crime scene photos into the technology age. The use of high resolution technology will assist law enforcement in making better use of crime scene photography and positive identification of prints. Valuable court room and investigation time can be saved and better served by this accurate, performance based process. Inconclusive evidence does not lead to convictions. Enhancement of the photographic capability helps solve one major problem with crime scene photos, that if taken with standard equipment and without the benefit of enhancement software would be inconclusive, thus allowing guilty parties to be set free due to lack of evidence.

  19. High-Resolution Scintimammography: A Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Rachel F. Brem; Joelle M. Schoonjans; Douglas A. Kieper; Stan Majewski; Steven Goodman; Cahid Civelek

    2002-07-01

    This study evaluated a novel high-resolution breast-specific gamma camera (HRBGC) for the detection of suggestive breast lesions. Methods: Fifty patients (with 58 breast lesions) for whom a scintimammogram was clinically indicated were prospectively evaluated with a general-purpose gamma camera and a novel HRBGC prototype. The results of conventional and high-resolution nuclear studies were prospectively classified as negative (normal or benign) or positive (suggestive or malignant) by 2 radiologists who were unaware of the mammographic and histologic results. All of the included lesions were confirmed by pathology. Results: There were 30 benign and 28 malignant lesions. The sensitivity for detection of breast cancer was 64.3% (18/28) with the conventional camera and 78.6% (22/28) with the HRBGC. The specificity with both systems was 93.3% (28/30). For the 18 nonpalpable lesions, sensitivity was 55.5% (10/18) and 72.2% (13/18) with the general-purpose camera and the HRBGC, respectively. For lesions 1 cm, 7 of 15 were detected with the general-purpose camera and 10 of 15 with the HRBGC. Four lesions (median size, 8.5 mm) were detected only with the HRBGC and were missed by the conventional camera. Conclusion: Evaluation of indeterminate breast lesions with an HRBGC results in improved sensitivity for the detection of cancer, with greater improvement shown for nonpalpable and 1-cm lesions.

  20. High resolution studies of barium Rydberg states

    International Nuclear Information System (INIS)

    Eliel, E.R.

    1982-01-01

    The subtle structure of Rydberg states of barium with orbital angular momentum 0, 1, 2 and 3 is investigated. Some aspects of atomic theory for a configuration with two valence electrons are reviewed. The Multi Channel Quantum Defect Theory (MQDT) is concisely introduced as a convenient way to describe interactions between Rydberg series. Three high-resolution UV studies are presented. The first two, presenting results on a transition in indium and europium serve as an illustration of the frequency doubling technique. The third study is of hyperfine structure and isotope shifts in low-lying p states in Sr and Ba. An extensive study of the 6snp and 6snf Rydberg states of barium is presented with particular emphasis on the 6snf states. It is shown that the level structure cannot be fully explained with the model introduced earlier. Rather an effective two-body spin-orbit interaction has to be introduced to account for the observed splittings, illustrating that high resolution studies on Rydberg states offer an unique opportunity to determine the importance of such effects. Finally, the 6sns and 6snd series are considered. The hyperfine induced isotope shift in the simple excitation spectra to 6sns 1 S 0 is discussed and attention is paid to series perturbers. It is shown that level mixing parameters can easily be extracted from the experimental data. (Auth.)

  1. Principles of high resolution NMR in solids

    CERN Document Server

    Mehring, Michael

    1983-01-01

    The field of Nuclear Magnetic Resonance (NMR) has developed at a fascinating pace during the last decade. It always has been an extremely valuable tool to the organic chemist by supplying molecular "finger print" spectra at the atomic level. Unfortunately the high resolution achievable in liquid solutions could not be obtained in solids and physicists and physical chemists had to live with unresolved lines open to a wealth of curve fitting procedures and a vast amount of speculations. High resolution NMR in solids seemed to be a paradoxon. Broad structure­ less lines are usually encountered when dealing with NMR in solids. Only with the recent advent of mUltiple pulse, magic angle, cross-polarization, two-dimen­ sional and multiple-quantum spectroscopy and other techniques during the last decade it became possible to resolve finer details of nuclear spin interactions in solids. I have felt that graduate students, researchers and others beginning to get involved with these techniques needed a book which trea...

  2. High-Resolution PET Detector. Final report

    International Nuclear Information System (INIS)

    Karp, Joel

    2014-01-01

    The objective of this project was to develop an understanding of the limits of performance for a high resolution PET detector using an approach based on continuous scintillation crystals rather than pixelated crystals. The overall goal was to design a high-resolution detector, which requires both high spatial resolution and high sensitivity for 511 keV gammas. Continuous scintillation detectors (Anger cameras) have been used extensively for both single-photon and PET scanners, however, these instruments were based on NaI(Tl) scintillators using relatively large, individual photo-multipliers. In this project we investigated the potential of this type of detector technology to achieve higher spatial resolution through the use of improved scintillator materials and photo-sensors, and modification of the detector surface to optimize the light response function.We achieved an average spatial resolution of 3-mm for a 25-mm thick, LYSO continuous detector using a maximum likelihood position algorithm and shallow slots cut into the entrance surface

  3. Navigating Earthquake Physics with High-Resolution Array Back-Projection

    Science.gov (United States)

    Meng, Lingsen

    Understanding earthquake source dynamics is a fundamental goal of geophysics. Progress toward this goal has been slow due to the gap between state-of-art earthquake simulations and the limited source imaging techniques based on conventional low-frequency finite fault inversions. Seismic array processing is an alternative source imaging technique that employs the higher frequency content of the earthquakes and provides finer detail of the source process with few prior assumptions. While the back-projection provides key observations of previous large earthquakes, the standard beamforming back-projection suffers from low resolution and severe artifacts. This thesis introduces the MUSIC technique, a high-resolution array processing method that aims to narrow the gap between the seismic observations and earthquake simulations. The MUSIC is a high-resolution method taking advantage of the higher order signal statistics. The method has not been widely used in seismology yet because of the nonstationary and incoherent nature of the seismic signal. We adapt MUSIC to transient seismic signal by incorporating the Multitaper cross-spectrum estimates. We also adopt a "reference window" strategy that mitigates the "swimming artifact," a systematic drift effect in back projection. The improved MUSIC back projections allow the imaging of recent large earthquakes in finer details which give rise to new perspectives on dynamic simulations. In the 2011 Tohoku-Oki earthquake, we observe frequency-dependent rupture behaviors which relate to the material variation along the dip of the subduction interface. In the 2012 off-Sumatra earthquake, we image the complicated ruptures involving orthogonal fault system and an usual branching direction. This result along with our complementary dynamic simulations probes the pressure-insensitive strength of the deep oceanic lithosphere. In another example, back projection is applied to the 2010 M7 Haiti earthquake recorded at regional distance. The

  4. High Resolution Powder Diffraction and Structure Determination

    International Nuclear Information System (INIS)

    Cox, D. E.

    1999-01-01

    It is clear that high-resolution synchrotrons X-ray powder diffraction is a very powerful and convenient tool for material characterization and structure determination. Most investigations to date have been carried out under ambient conditions and have focused on structure solution and refinement. The application of high-resolution techniques to increasingly complex structures will certainly represent an important part of future studies, and it has been seen how ab initio solution of structures with perhaps 100 atoms in the asymmetric unit is within the realms of possibility. However, the ease with which temperature-dependence measurements can be made combined with improvements in the technology of position-sensitive detectors will undoubtedly stimulate precise in situ structural studies of phase transitions and related phenomena. One challenge in this area will be to develop high-resolution techniques for ultra-high pressure investigations in diamond anvil cells. This will require highly focused beams and very precise collimation in front of the cell down to dimensions of 50 (micro)m or less. Anomalous scattering offers many interesting possibilities as well. As a means of enhancing scattering contrast it has applications not only to the determination of cation distribution in mixed systems such as the superconducting oxides discussed in Section 9.5.3, but also to the location of specific cations in partially occupied sites, such as the extra-framework positions in zeolites, for example. Another possible application is to provide phasing information for ab initio structure solution. Finally, the precise determination of f as a function of energy through an absorption edge can provide useful information about cation oxidation states, particularly in conjunction with XANES data. In contrast to many experiments at a synchrotron facility, powder diffraction is a relatively simple and user-friendly technique, and most of the procedures and software for data analysis

  5. Human intracranial recordings link suppressed transients rather than 'filling-in' to perceptual continuity across blinks.

    Science.gov (United States)

    Golan, Tal; Davidesco, Ido; Meshulam, Meir; Groppe, David M; Mégevand, Pierre; Yeagle, Erin M; Goldfinger, Matthew S; Harel, Michal; Melloni, Lucia; Schroeder, Charles E; Deouell, Leon Y; Mehta, Ashesh D; Malach, Rafael

    2016-09-29

    We hardly notice our eye blinks, yet an externally generated retinal interruption of a similar duration is perceptually salient. We examined the neural correlates of this perceptual distinction using intracranially measured ECoG signals from the human visual cortex in 14 patients. In early visual areas (V1 and V2), the disappearance of the stimulus due to either invisible blinks or salient blank video frames ('gaps') led to a similar drop in activity level, followed by a positive overshoot beyond baseline, triggered by stimulus reappearance. Ascending the visual hierarchy, the reappearance-related overshoot gradually subsided for blinks but not for gaps. By contrast, the disappearance-related drop did not follow the perceptual distinction - it was actually slightly more pronounced for blinks than for gaps. These findings suggest that blinks' limited visibility compared with gaps is correlated with suppression of blink-related visual activity transients, rather than with "filling-in" of the occluded content during blinks.

  6. Chromatic Modulator for High Resolution CCD or APS Devices

    Science.gov (United States)

    Hartley, Frank T. (Inventor); Hull, Anthony B. (Inventor)

    2003-01-01

    A system for providing high-resolution color separation in electronic imaging. Comb drives controllably oscillate a red-green-blue (RGB) color strip filter system (or otherwise) over an electronic imaging system such as a charge-coupled device (CCD) or active pixel sensor (APS). The color filter is modulated over the imaging array at a rate three or more times the frame rate of the imaging array. In so doing, the underlying active imaging elements are then able to detect separate color-separated images, which are then combined to provide a color-accurate frame which is then recorded as the representation of the recorded image. High pixel resolution is maintained. Registration is obtained between the color strip filter and the underlying imaging array through the use of electrostatic comb drives in conjunction with a spring suspension system.

  7. High resolution CT of the lung

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Harumi (Kyoto Univ. (Japan). Faculty of Medicine)

    1991-02-01

    The emergence of computed tomography (CT) in the early 1970s has greatly contributed to diagnostic radiology. The brain was the first organ examined with CT, followed by the abdomen. For the chest, CT has also come into use shortly after the introduction in the examination of the thoracic cavity and mediastinum. CT techniques were, however, of limited significance in the evaluation of pulmonary diseases, especially diffuse pulmonary diseases. High-resolution CT (HRCT) has been introduced in clinical investigations of the lung field. This article is designed to present chest radiographic and conventional tomographic interpretations and to introduce findings of HRCT corresponding to the same shadows, with a summation of the significance of HRCT and issues of diagnostic imaging. Materials outlined are tuberculosis, pneumoconiosis, bronchopneumonia, mycoplasma pneumonia, lymphangitic carcinomatosis, sarcoidosis, diffuse panbronchiolitis, interstitial pneumonia, and pulmonary emphysema. Finally, an overview of basic investigations evolved from HRCT is given. (N.K.) 140 refs.

  8. Constructing a WISE High Resolution Galaxy Atlas

    Science.gov (United States)

    Jarrett, T. H.; Masci, F.; Tsai, C. W.; Petty, S.; Cluver, M.; Assef, Roberto J.; Benford, D.; Blain, A.; Bridge, C.; Donoso, E.; hide

    2012-01-01

    After eight months of continuous observations, the Wide-field Infrared Survey Explorer (WISE) mapped the entire sky at 3.4 micron, 4.6 micron, 12 micron, and 22 micron. We have begun a dedicated WISE High Resolution Galaxy Atlas project to fully characterize large, nearby galaxies and produce a legacy image atlas and source catalog. Here we summarize the deconvolution techniques used to significantly improve the spatial resolution of WISE imaging, specifically designed to study the internal anatomy of nearby galaxies. As a case study, we present results for the galaxy NGC 1566, comparing the WISE enhanced-resolution image processing to that of Spitzer, Galaxy Evolution Explorer, and ground-based imaging. This is the first paper in a two-part series; results for a larger sample of nearby galaxies are presented in the second paper.

  9. A high resolution jet analysis for LEP

    International Nuclear Information System (INIS)

    Hariri, S.

    1992-11-01

    A high resolution multijet analysis of hadronic events produced in e + e - annihilation at a C.M.S. energy of 91.2 GeV is described. Hadronic events produced in e + e - annihilations are generated using the Monte Carlo program JETSET7.3 with its two options: Matrix Element (M.E.) and Parton Showers (P.S.). The shower option is used with its default parameter values while the M.E. option is used with an invariant mass cut Y CUT =0.01 instead of 0.02. This choice ensures a better continuity in the evolution of the event shape variables. (K.A.) 3 refs.; 26 figs.; 1 tab

  10. High Resolution Displays Using NCAP Liquid Crystals

    Science.gov (United States)

    Macknick, A. Brian; Jones, Phil; White, Larry

    1989-07-01

    Nematic curvilinear aligned phase (NCAP) liquid crystals have been found useful for high information content video displays. NCAP materials are liquid crystals which have been encapsulated in a polymer matrix and which have a light transmission which is variable with applied electric fields. Because NCAP materials do not require polarizers, their on-state transmission is substantially better than twisted nematic cells. All dimensional tolerances are locked in during the encapsulation process and hence there are no critical sealing or spacing issues. By controlling the polymer/liquid crystal morphology, switching speeds of NCAP materials have been significantly improved over twisted nematic systems. Recent work has combined active matrix addressing with NCAP materials. Active matrices, such as thin film transistors, have given displays of high resolution. The paper will discuss the advantages of NCAP materials specifically designed for operation at video rates on transistor arrays; applications for both backlit and projection displays will be discussed.

  11. High resolution VUV facility at INDUS-1

    International Nuclear Information System (INIS)

    Krishnamurty, G.; Saraswathy, P.; Rao, P.M.R.; Mishra, A.P.; Kartha, V.B.

    1993-01-01

    Synchrotron radiation (SR) generated in the electron storage rings is an unique source for the study of atomic and molecular spectroscopy especially in the vacuum ultra violet region. Realizing the potential of this light source, efforts are in progress to develop a beamline facility at INDUS-1 to carry out high resolution atomic and molecular spectroscopy. This beam line consists of a fore-optic which is a combination of three cylindrical mirrors. The mirrors are so chosen that SR beam having a 60 mrad (horizontal) x 6 mrad (vertical) divergence is focussed onto a slit of a 6.65 metre off-plane spectrometer in Eagle Mount equipped with horizontal slit and vertical dispersion. The design of the various components of the beam line is completed. It is decided to build the spectrometer as per the requirements of the user community. Details of the various aspects of the beam line will be presented. (author). 3 figs

  12. High-resolution CT of airway reactivity

    International Nuclear Information System (INIS)

    Herold, C.J.; Brown, R.H.; Hirshman, C.A.; Mitzner, W.; Zerhouni, E.A.

    1990-01-01

    Assessment of airway reactivity has generally been limited to experimental nonimaging models. This authors of this paper used high-resolution CT (HRCT) to evaluate airway reactivity and to calculate airway resistance (Raw) compared with lung resistance (RL). Ten anesthetized and ventilated dogs were investigated with HRCT (10 contiguous 2-mm sections through the lower lung lobes) during control state, following aerosol histamine challenge, and following posthistamine hyperinflation. The HRCT scans were digitized, and areas of 10 airways per dog (diameter, 1-10 mm) were measured with a computer edging process. Changes in airway area and Raw (calculated by 1/[area] 2 ) were measured. RL was assessed separately, following the same protocol. Data were analyzed by use of a paired t-test with significance at p < .05

  13. High resolution crystal calorimetry at LHC

    International Nuclear Information System (INIS)

    Schneegans, M.; Ferrere, D.; Lebeau, M.; Vivargent, M.

    1991-01-01

    The search for Higgs bosons above Lep200 reach could be one of the main tasks of the future pp and ee colliders. In the intermediate mass region, and in particular in the range 80-140 GeV/c 2 , only the 2-photon decay mode of a Higgs produced inclusively or in association with a W, gives a good chance of observation. A 'dedicated' very high resolution calorimeter with photon angle reconstruction and pion identification capability should detect a Higgs signal with high probability. A crystal calorimeter can be considered as a conservative approach to such a detector, since a large design and operation experience already exists. The extensive R and D needed for finding a dense, fast and radiation hard crystal, is under way. Guide-lines for designing an optimum calorimeter for LHC are discussed and preliminary configurations are given. (author) 7 refs., 3 figs., 2 tabs

  14. High resolution tomography using analog coding

    International Nuclear Information System (INIS)

    Brownell, G.L.; Burnham, C.A.; Chesler, D.A.

    1985-01-01

    As part of a 30-year program in the development of positron instrumentation, the authors have developed a high resolution bismuth germanate (BGO) ring tomography (PCR) employing 360 detectors and 90 photomultiplier tubes for one plane. The detectors are shaped as trapezoid and are 4 mm wide at the front end. When assembled, they form an essentially continuous cylindrical detector. Light from a scintillation in the detector is viewed through a cylindrical light pipe by the photomultiplier tubes. By use of an analog coding scheme, the detector emitting light is identified from the phototube signals. In effect, each phototube can identify four crystals. PCR is designed as a static device and does not use interpolative motion. This results in considerable advantage when performing dynamic studies. PCR is the positron tomography analog of the γ-camera widely used in nuclear medicine

  15. High-resolution CT of otosclerosis

    International Nuclear Information System (INIS)

    Dewen, Yang; Kodama, Takao; Tono, Tetsuya; Ochiai, Reiji; Kiyomizu, Kensuke; Suzuki, Yukiko; Yano, Takanori; Watanabe, Katsushi

    1997-01-01

    High-resolution CT (HRCT) scans of thirty-two patients (60 ears) with the clinical diagnosis of fenestral otosclerosis were evaluated retrospectively. HRCT was performed with 1-mm-thick targeted sections and 1-mm (36 ears) or 0.5-mm (10 ears) intervals in the semiaxial projection. Seven patients (14 ears) underwent helical scanning with a 1-mm slice thickness and 1-mm/sec table speed. Forty-five ears (75%) were found to have one or more otospongiotic or otosclerotic foci on HRCT. In most instances (30 ears), the otospongiotic foci were found in the region of the fissula ante fenestram. No significant correlations between CT findings and air conduction threshold were observed. We found a significant relationship between lesions of the labyrinthine capsule and sensorineural hearing loss. We conclude that HRCT is a valuable modality for diagnosing otosclerosis, especially when otospongiotic focus is detected. (author)

  16. High resolution CT in pulmonary sarcoidosis

    International Nuclear Information System (INIS)

    Spina, Juan C.; Curros, Marisela L.; Gomez, M.; Gonzalez, A.; Chacon, Carolina; Guerendiain, G.

    2000-01-01

    Objectives: To establish the particular advantages of High Resolution CT (HRCT) for the diagnosis of pulmonary sarcoidosis. Material and Methods: A series of fourteen patients, (4 men and 10 women; mean age 44,5 years) with thoracic sarcoidosis. All patients were studied using HRCT and diagnosis was confirmed for each case. Confidence intervals were obtained for different disease manifestations. Results: The most common findings were: lymph node enlargement (n=14 patients), pulmonary nodules (n=13), thickening of septa (n=6), peribronquial vascular thickening (n=5) pulmonary pseudo mass (n=5) and signs of fibrosis (n=4). The stage most commonly observed was stage II. It is worth noting that no cases of pleural effusion or cavitations of pulmonary lesions were observed. Conclusions: In this series, confidence interval overlapping for lymph node enlargement, single pulmonary nodules and septum thickening, allows to infer that their presence in a young adult, with few clinical symptoms, forces to rule out first the possibility of sarcoidosis. (author)

  17. Improved methods for high resolution electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, J.R.

    1987-04-01

    Existing methods of making support films for high resolution transmission electron microscopy are investigated and novel methods are developed. Existing methods of fabricating fenestrated, metal reinforced specimen supports (microgrids) are evaluated for their potential to reduce beam induced movement of monolamellar crystals of C/sub 44/H/sub 90/ paraffin supported on thin carbon films. Improved methods of producing hydrophobic carbon films by vacuum evaporation, and improved methods of depositing well ordered monolamellar paraffin crystals on carbon films are developed. A novel technique for vacuum evaporation of metals is described which is used to reinforce microgrids. A technique is also developed to bond thin carbon films to microgrids with a polymer bonding agent. Unique biochemical methods are described to accomplish site specific covalent modification of membrane proteins. Protocols are given which covalently convert the carboxy terminus of papain cleaved bacteriorhodopsin to a free thiol. 53 refs., 19 figs., 1 tab.

  18. High resolution infrared spectroscopy of symbiotic stars

    International Nuclear Information System (INIS)

    Bensammar, S.

    1989-01-01

    We report here very early results of high resolution (5x10 3 - 4x10 4 ) infrared spectroscopy (1 - 2.5 μm) of different symbiotic stars (T CrB, RW Hya, CI Cyg, PU Vul) observed with the Fourier Transform Spectrometer of the 3.60m Canada France Hawaii Telescope. These stars are usually considered as interacting binaries and only little details are known about the nature of their cool component. CO absorption lines are detected for the four stars. Very different profiles of hydrogen Brackett γ and helium 10830 A lines are shown for CI Cyg observed at different phases, while Pu Vul shows very intense emission lines

  19. GRANULOMETRIC MAPS FROM HIGH RESOLUTION SATELLITE IMAGES

    Directory of Open Access Journals (Sweden)

    Catherine Mering

    2011-05-01

    Full Text Available A new method of land cover mapping from satellite images using granulometric analysis is presented here. Discontinuous landscapes such as steppian bushes of semi arid regions and recently growing urban settlements are especially concerned by this study. Spatial organisations of the land cover are quantified by means of the size distribution analysis of the land cover units extracted from high resolution remotely sensed images. A granulometric map is built by automatic classification of every pixel of the image according to the granulometric density inside a sliding neighbourhood. Granulometric mapping brings some advantages over traditional thematic mapping by remote sensing by focusing on fine spatial events and small changes in one peculiar category of the landscape.

  20. Non-linear transient behavior during soil liquefaction based on re-evaluation of seismic records

    OpenAIRE

    Kamagata, S.; Takewaki, Izuru

    2015-01-01

    Focusing on soil liquefaction, the seismic records during the Niigata-ken earthquake in 1964, the southern Hyogo prefecture earthquake in 1995 and the 2011 off the Pacific coast of Tohoku earthquake are analyzed by the non-stationary Fourier spectra. The shift of dominant frequency in the seismic record of Kawagishi-cho during the Niigata-ken earthquake is evaluated based on the time-variant property of dominant frequencies. The reduction ratio of the soil stiffness is evaluated from the shif...

  1. High resolution tsunami inversion for 2010 Chile earthquake

    Directory of Open Access Journals (Sweden)

    T.-R. Wu

    2011-12-01

    Full Text Available We investigate the feasibility of inverting high-resolution vertical seafloor displacement from tsunami waveforms. An inversion method named "SUTIM" (small unit tsunami inversion method is developed to meet this goal. In addition to utilizing the conventional least-square inversion, this paper also enhances the inversion resolution by Grid-Shifting method. A smooth constraint is adopted to gain stability. After a series of validation and performance tests, SUTIM is used to study the 2010 Chile earthquake. Based upon data quality and azimuthal distribution, we select tsunami waveforms from 6 GLOSS stations and 1 DART buoy record. In total, 157 sub-faults are utilized for the high-resolution inversion. The resolution reaches 10 sub-faults per wavelength. The result is compared with the distribution of the aftershocks and waveforms at each gauge location with very good agreement. The inversion result shows that the source profile features a non-uniform distribution of the seafloor displacement. The highly elevated vertical seafloor is mainly concentrated in two areas: one is located in the northern part of the epicentre, between 34° S and 36° S; the other is in the southern part, between 37° S and 38° S.

  2. High resolution tsunami inversion for 2010 Chile earthquake

    Science.gov (United States)

    Wu, T.-R.; Ho, T.-C.

    2011-12-01

    We investigate the feasibility of inverting high-resolution vertical seafloor displacement from tsunami waveforms. An inversion method named "SUTIM" (small unit tsunami inversion method) is developed to meet this goal. In addition to utilizing the conventional least-square inversion, this paper also enhances the inversion resolution by Grid-Shifting method. A smooth constraint is adopted to gain stability. After a series of validation and performance tests, SUTIM is used to study the 2010 Chile earthquake. Based upon data quality and azimuthal distribution, we select tsunami waveforms from 6 GLOSS stations and 1 DART buoy record. In total, 157 sub-faults are utilized for the high-resolution inversion. The resolution reaches 10 sub-faults per wavelength. The result is compared with the distribution of the aftershocks and waveforms at each gauge location with very good agreement. The inversion result shows that the source profile features a non-uniform distribution of the seafloor displacement. The highly elevated vertical seafloor is mainly concentrated in two areas: one is located in the northern part of the epicentre, between 34° S and 36° S; the other is in the southern part, between 37° S and 38° S.

  3. Dynamic high resolution imaging of rats

    International Nuclear Information System (INIS)

    Miyaoka, R.S.; Lewellen, T.K.; Bice, A.N.

    1990-01-01

    A positron emission tomography with the sensitivity and resolution to do dynamic imaging of rats would be an invaluable tool for biological researchers. In this paper, the authors determine the biological criteria for dynamic positron emission imaging of rats. To be useful, 3 mm isotropic resolution and 2-3 second time binning were necessary characteristics for such a dedicated tomograph. A single plane in which two objects of interest could be imaged simultaneously was considered acceptable. Multi-layered detector designs were evaluated as a possible solution to the dynamic imaging and high resolution imaging requirements. The University of Washington photon history generator was used to generate data to investigate a tomograph's sensitivity to true, scattered and random coincidences for varying detector ring diameters. Intrinsic spatial uniformity advantages of multi-layered detector designs over conventional detector designs were investigated using a Monte Carlo program. As a result, a modular three layered detector prototype is being developed. A module will consist of a layer of five 3.5 mm wide crystals and two layers of six 2.5 mm wide crystals. The authors believe adequate sampling can be achieved with a stationary detector system using these modules. Economical crystal decoding strategies have been investigated and simulations have been run to investigate optimum light channeling methods for block decoding strategies. An analog block decoding method has been proposed and will be experimentally evaluated to determine whether it can provide the desired performance

  4. High resolution computed tomography of positron emitters

    International Nuclear Information System (INIS)

    Derenzo, S.E.; Budinger, T.F.; Cahoon, J.L.; Huesman, R.H.; Jackson, H.G.

    1976-10-01

    High resolution computed transaxial radionuclide tomography has been performed on phantoms containing positron-emitting isotopes. The imaging system consisted of two opposing groups of eight NaI(Tl) crystals 8 mm x 30 mm x 50 mm deep and the phantoms were rotated to measure coincident events along 8960 projection integrals as they would be measured by a 280-crystal ring system now under construction. The spatial resolution in the reconstructed images is 7.5 mm FWHM at the center of the ring and approximately 11 mm FWHM at a radius of 10 cm. We present measurements of imaging and background rates under various operating conditions. Based on these measurements, the full 280-crystal system will image 10,000 events per sec with 400 μCi in a section 1 cm thick and 20 cm in diameter. We show that 1.5 million events are sufficient to reliably image 3.5-mm hot spots with 14-mm center-to-center spacing and isolated 9-mm diameter cold spots in phantoms 15 to 20 cm in diameter

  5. High speed, High resolution terahertz spectrometers

    International Nuclear Information System (INIS)

    Kim, Youngchan; Yee, Dae Su; Yi, Miwoo; Ahn, Jaewook

    2008-01-01

    A variety of sources and methods have been developed for terahertz spectroscopy during almost two decades. Terahertz time domain spectroscopy (THz TDS)has attracted particular attention as a basic measurement method in the fields of THz science and technology. Recently, asynchronous optical sampling (AOS)THz TDS has been demonstrated, featuring rapid data acquisition and a high spectral resolution. Also, terahertz frequency comb spectroscopy (TFCS)possesses attractive features for high precision terahertz spectroscopy. In this presentation, we report on these two types of terahertz spectrometer. Our high speed, high resolution terahertz spectrometer is demonstrated using two mode locked femtosecond lasers with slightly different repetition frequencies without a mechanical delay stage. The repetition frequencies of the two femtosecond lasers are stabilized by use of two phase locked loops sharing the same reference oscillator. The time resolution of our terahertz spectrometer is measured using the cross correlation method to be 270 fs. AOS THz TDS is presented in Fig. 1, which shows a time domain waveform rapidly acquired on a 10ns time window. The inset shows a zoom into the signal with 100ps time window. The spectrum obtained by the fast Fourier Transformation (FFT)of the time domain waveform has a frequency resolution of 100MHz. The dependence of the signal to noise ratio (SNR)on the measurement time is also investigated

  6. High resolution CT of temporal bone trauma

    International Nuclear Information System (INIS)

    Youn, Eun Kyung

    1986-01-01

    Radiographic studies of the temporal bone following head trauma are indicated when there is cerebrospinal fluid otorrhea or rhinorrhoea, hearing loss, or facial nerve paralysis. Plain radiography displays only 17-30% of temporal bone fractures and pluridirectional tomography is both difficult to perform, particularly in the acutely ill patient, and less satisfactory for the demonstration of fine fractures. Consequently, high resolution CT is the imaging method of choice for the investigation of suspected temporal bone trauma and allows special resolution of fine bony detail comparable to that attainable by conventional tomography. Eight cases of temporal bone trauma examined at Korea General Hospital April 1985 through May 1986. The results were as follows: Seven patients (87%) suffered longitudinal fractures. In 6 patients who had purely conductive hearing loss, CT revealed various ossicular chain abnormality. In one patient who had neuro sensory hearing loss, CT demonstrated intract ossicular with a fracture nearing lateral wall of the lateral semicircular canal. In one patient who had mixed hearing loss, CT showed complex fracture.

  7. High resolution SETI: Experiences and prospects

    Science.gov (United States)

    Horowitz, Paul; Clubok, Ken

    Megachannel spectroscopy with sub-Hertz resolution constitutes an attractive strategy for a microwave search for extraterrestrial intelligence (SETI), assuming the transmission of a narrowband radiofrequency beacon. Such resolution matches the properties of the interstellar medium, and the necessary Doppler corrections provide a high degree of interference rejection. We have constructed a frequency-agile receiver with an FFT-based 8 megachannel digital spectrum analyzer, on-line signal recognition, and multithreshold archiving. We are using it to conduct a meridian transit search of the northern sky at the Harvard-Smithsonian 26-m antenna, with a second identical system scheduled to begin observations in Argentina this month. Successive 400 kHz spectra, at 0.05 Hz resolution, are searched for features characteristic of an intentional narrowband beacon transmission. These spectra are centered on guessable frequencies (such as λ21 cm), referenced successively to the local standard of rest, the galactic barycenter, and the cosmic blackbody rest frame. This search has rejected interference admirably, but is greatly limited both in total frequency coverage and sensitivity to signals other than carriers. We summarize five years of high resolution SETI at Harvard, in the context of answering the questions "How useful is narrowband SETI, how serious are its limitations, what can be done to circumvent them, and in what direction should SETI evolve?" Increasingly powerful signal processing hardware, combined with ever-higher memory densities, are particularly relevant, permitting the construction of compact and affordable gigachannel spectrum analyzers covering hundreds of megahertz of instantaneous bandwidth.

  8. High-resolution CCD imaging alternatives

    Science.gov (United States)

    Brown, D. L.; Acker, D. E.

    1992-08-01

    High resolution CCD color cameras have recently stimulated the interest of a large number of potential end-users for a wide range of practical applications. Real-time High Definition Television (HDTV) systems are now being used or considered for use in applications ranging from entertainment program origination through digital image storage to medical and scientific research. HDTV generation of electronic images offers significant cost and time-saving advantages over the use of film in such applications. Further in still image systems electronic image capture is faster and more efficient than conventional image scanners. The CCD still camera can capture 3-dimensional objects into the computing environment directly without having to shoot a picture on film develop it and then scan the image into a computer. 2. EXTENDING CCD TECHNOLOGY BEYOND BROADCAST Most standard production CCD sensor chips are made for broadcast-compatible systems. One popular CCD and the basis for this discussion offers arrays of roughly 750 x 580 picture elements (pixels) or a total array of approximately 435 pixels (see Fig. 1). FOR. A has developed a technique to increase the number of available pixels for a given image compared to that produced by the standard CCD itself. Using an inter-lined CCD with an overall spatial structure several times larger than the photo-sensitive sensor areas each of the CCD sensors is shifted in two dimensions in order to fill in spatial gaps between adjacent sensors.

  9. High resolution simultaneous measurements of airborne radionuclides

    International Nuclear Information System (INIS)

    Abe, T.; Yamaguchi, Y.; Tanaka, K.; Komura, K.

    2006-01-01

    High resolution (2-3 hrs) simultaneous measurements of airborne radionuclides, 212 Pb, 210 Pb and 7 Be, have been performed by using extremely low background Ge detectors at Ogoya Underground Laboratory. We have measured above radionuclides at three monitoring points viz, 1) Low Level Radioactivity Laboratory (LLRL) Kanazawa University, 2) Shishiku Plateau (640 m MSL) located about 8 km from LLRL to investigate vertical difference of activity levels, and 3) Hegura Island (10 m MSL) located about 50 km from Noto Peninsula in the Sea of Japan to evaluate the influences of Asian continent or mainland of Japan on the variation to the activity levels. Variations of short-lived 212 Pb concentration showed noticeable time lags between at LLRL and at Shishiku Plateau. These time lags might be caused by change of height of a planetary boundary layer. On the contrary, variations of long-lived 210 Pb and 7 Be showed simultaneity at three locations because of homogeneity of these concentrations all over the area. (author)

  10. Processing method for high resolution monochromator

    International Nuclear Information System (INIS)

    Kiriyama, Koji; Mitsui, Takaya

    2006-12-01

    A processing method for high resolution monochromator (HRM) has been developed at Japanese Atomic Energy Agency/Quantum Beam Science Directorate/Synchrotron Radiation Research unit at SPring-8. For manufacturing a HRM, a sophisticated slicing machine and X-ray diffractometer have been installed for shaping a crystal ingot and orienting precisely the surface of a crystal ingot, respectively. The specification of the slicing machine is following; Maximum size of a diamond blade is φ 350mm in diameter, φ 38.1mm in the spindle diameter, and 2mm in thickness. A large crystal such as an ingot with 100mm in diameter, 200mm in length can be cut. Thin crystal samples such as a wafer can be also cut using by another sample holder. Working distance of a main shaft with the direction perpendicular to working table in the machine is 350mm at maximum. Smallest resolution of the main shaft with directions of front-and-back and top-and-bottom are 0.001mm read by a digital encoder. 2mm/min can set for cutting samples in the forward direction. For orienting crystal faces relative to the blade direction adjustment, a one-circle goniometer and 2-circle segment are equipped on the working table in the machine. A rotation and a tilt of the stage can be done by manual operation. Digital encoder in a turn stage is furnished and has angle resolution of less than 0.01 degrees. In addition, a hand drill as a supporting device for detailed processing of crystal is prepared. Then, an ideal crystal face can be cut from crystal samples within an accuracy of about 0.01 degrees. By installation of these devices, a high energy resolution monochromator crystal for inelastic x-ray scattering and a beam collimator are got in hand and are expected to be used for nanotechnology studies. (author)

  11. Zeolites - a high resolution electron microscopy study

    International Nuclear Information System (INIS)

    Alfredsson, V.

    1994-10-01

    High resolution transmission electron microscopy (HRTEM) has been used to investigate a number of zeolites (EMT, FAU, LTL, MFI and MOR) and a member of the mesoporous M41S family. The electron optical artefact, manifested as a dark spot in the projected centre of the large zeolite channels, caused by insufficient transfer of certain reflections in the objective lens has been explained. The artefact severely hinders observation of materials confined in the zeolite channels and cavities. It is shown how to circumvent the artefact problem and how to image confined materials in spite of disturbance caused by the artefact. Image processing by means of a Wiener filter has been applied for removal of the artefact. The detailed surface structure of FAU has been investigated. Comparison of experimental micrographs with images simulated using different surface models indicates that the surface can be terminated in different ways depending on synthesis methods. The dealuminated form of FAU (USY) is covered by an amorphous region. Platinum incorporated in FAU has a preponderance to aggregate in the (111) twin planes, probably due to a local difference in cage structure with more spacious cages. It is shown that platinum is intra-zeolitic as opposed to being located on the external surface of the zeolite crystal. This could be deduced from tomography of ultra-thin sections among observations. HRTEM studies of the mesoporous MCM-41 show that the pores have a hexagonal shape and also supports the mechanistic model proposed which involves a cooperative formation of a mesophase including the silicate species as well as the surfactant. 66 refs, 24 figs

  12. High-resolution downscaling for hydrological management

    Science.gov (United States)

    Ulbrich, Uwe; Rust, Henning; Meredith, Edmund; Kpogo-Nuwoklo, Komlan; Vagenas, Christos

    2017-04-01

    Hydrological modellers and water managers require high-resolution climate data to model regional hydrologies and how these may respond to future changes in the large-scale climate. The ability to successfully model such changes and, by extension, critical infrastructure planning is often impeded by a lack of suitable climate data. This typically takes the form of too-coarse data from climate models, which are not sufficiently detailed in either space or time to be able to support water management decisions and hydrological research. BINGO (Bringing INnovation in onGOing water management; ) aims to bridge the gap between the needs of hydrological modellers and planners, and the currently available range of climate data, with the overarching aim of providing adaptation strategies for climate change-related challenges. Producing the kilometre- and sub-daily-scale climate data needed by hydrologists through continuous simulations is generally computationally infeasible. To circumvent this hurdle, we adopt a two-pronged approach involving (1) selective dynamical downscaling and (2) conditional stochastic weather generators, with the former presented here. We take an event-based approach to downscaling in order to achieve the kilometre-scale input needed by hydrological modellers. Computational expenses are minimized by identifying extremal weather patterns for each BINGO research site in lower-resolution simulations and then only downscaling to the kilometre-scale (convection permitting) those events during which such patterns occur. Here we (1) outline the methodology behind the selection of the events, and (2) compare the modelled precipitation distribution and variability (preconditioned on the extremal weather patterns) with that found in observations.

  13. Toward high-resolution optoelectronic retinal prosthesis

    Science.gov (United States)

    Palanker, Daniel; Huie, Philip; Vankov, Alexander; Asher, Alon; Baccus, Steven

    2005-04-01

    It has been already demonstrated that electrical stimulation of retina can produce visual percepts in blind patients suffering from macular degeneration and retinitis pigmentosa. Current retinal implants provide very low resolution (just a few electrodes), while several thousand pixels are required for functional restoration of sight. We present a design of the optoelectronic retinal prosthetic system that can activate a retinal stimulating array with pixel density up to 2,500 pix/mm2 (geometrically corresponding to a visual acuity of 20/80), and allows for natural eye scanning rather than scanning with a head-mounted camera. The system operates similarly to "virtual reality" imaging devices used in military and medical applications. An image from a video camera is projected by a goggle-mounted infrared LED-LCD display onto the retina, activating an array of powered photodiodes in the retinal implant. Such a system provides a broad field of vision by allowing for natural eye scanning. The goggles are transparent to visible light, thus allowing for simultaneous utilization of remaining natural vision along with prosthetic stimulation. Optical control of the implant allows for simple adjustment of image processing algorithms and for learning. A major prerequisite for high resolution stimulation is the proximity of neural cells to the stimulation sites. This can be achieved with sub-retinal implants constructed in a manner that directs migration of retinal cells to target areas. Two basic implant geometries are described: perforated membranes and protruding electrode arrays. Possibility of the tactile neural stimulation is also examined.

  14. High Resolution Energetic X-ray Imager (HREXI)

    Science.gov (United States)

    Grindlay, Jonathan

    We propose to design and build the first imaging hard X-ray detector system that incorporates 3D stacking of closely packed detector readouts in finely-spaced imaging arrays with their required data processing and control electronics. In virtually all imaging astronomical detectors, detector readout is done with flex connectors or connections that are not vertical but rather horizontal , requiring loss of focal plane area. For high resolution pixel detectors needed for high speed event-based X-ray imaging, from low energy applications (CMOS) with focusing X-ray telescopes, to hard X-ray applications with pixelated CZT for large area coded aperture telescopes, this new detector development offers great promise. We propose to extend our previous and current APRA supported ProtoEXIST program that has developed the first large area imaging CZT detectors and demonstrated their astrophysical capabilities on two successful balloon flight to a next generation High Resolution Energetic X-ray Imager (HREXI), which would incorporate microvia technology for the first time to connect the readout ASIC on each CZT crystal directly to its control and data processing system. This 3-dimensional stacking of detector and readout/control system means that large area (>2m2) imaging detector planes for a High Resolution Wide-field hard X-ray telescope can be built with initially greatly reduced detector gaps and ultimately with no gaps. This increases detector area, efficiency, and simplicity of detector integration. Thus higher sensitivity wide-field imagers will be possible at lower cost. HREXI will enable a post-Swift NASA mission such as the EREXS concept proposed to PCOS to be conducted as a future MIDEX mission. This mission would conduct a high resolution (<2 arcmin) , broad band (5 200 keV) hard X-ray survey of black holes on all scales with ~10X higher sensitivity than Swift. In the current era of Time Domain Astrophysics, such a survey capability, in conjunction with a n

  15. HIGH RESOLUTION AIRBORNE SHALLOW WATER MAPPING

    Directory of Open Access Journals (Sweden)

    F. Steinbacher

    2012-07-01

    Full Text Available In order to meet the requirements of the European Water Framework Directive (EU-WFD, authorities face the problem of repeatedly performing area-wide surveying of all kinds of inland waters. Especially for mid-sized or small rivers this is a considerable challenge imposing insurmountable logistical efforts and costs. It is therefore investigated if large-scale surveying of a river system on an operational basis is feasible by employing airborne hydrographic laser scanning. In cooperation with the Bavarian Water Authority (WWA Weilheim a pilot project was initiated by the Unit of Hydraulic Engineering at the University of Innsbruck and RIEGL Laser Measurement Systems exploiting the possibilities of a new LIDAR measurement system with high spatial resolution and high measurement rate to capture about 70 km of riverbed and foreland for the river Loisach in Bavaria/Germany and the estuary and parts of the shoreline (about 40km in length of lake Ammersee. The entire area surveyed was referenced to classic terrestrial cross-section surveys with the aim to derive products for the monitoring and managing needs of the inland water bodies forced by the EU-WFD. The survey was performed in July 2011 by helicopter and airplane and took 3 days in total. In addition, high resolution areal images were taken to provide an optical reference, offering a wide range of possibilities on further research, monitoring, and managing responsibilities. The operating altitude was about 500 m to maintain eye-safety, even for the aided eye, the airspeed was about 55 kts for the helicopter and 75 kts for the aircraft. The helicopter was used in the alpine regions while the fixed wing aircraft was used in the plains and the urban area, using appropriate scan rates to receive evenly distributed point clouds. The resulting point density ranged from 10 to 25 points per square meter. By carefully selecting days with optimum water quality, satisfactory penetration down to the river

  16. High Resolution Airborne Shallow Water Mapping

    Science.gov (United States)

    Steinbacher, F.; Pfennigbauer, M.; Aufleger, M.; Ullrich, A.

    2012-07-01

    In order to meet the requirements of the European Water Framework Directive (EU-WFD), authorities face the problem of repeatedly performing area-wide surveying of all kinds of inland waters. Especially for mid-sized or small rivers this is a considerable challenge imposing insurmountable logistical efforts and costs. It is therefore investigated if large-scale surveying of a river system on an operational basis is feasible by employing airborne hydrographic laser scanning. In cooperation with the Bavarian Water Authority (WWA Weilheim) a pilot project was initiated by the Unit of Hydraulic Engineering at the University of Innsbruck and RIEGL Laser Measurement Systems exploiting the possibilities of a new LIDAR measurement system with high spatial resolution and high measurement rate to capture about 70 km of riverbed and foreland for the river Loisach in Bavaria/Germany and the estuary and parts of the shoreline (about 40km in length) of lake Ammersee. The entire area surveyed was referenced to classic terrestrial cross-section surveys with the aim to derive products for the monitoring and managing needs of the inland water bodies forced by the EU-WFD. The survey was performed in July 2011 by helicopter and airplane and took 3 days in total. In addition, high resolution areal images were taken to provide an optical reference, offering a wide range of possibilities on further research, monitoring, and managing responsibilities. The operating altitude was about 500 m to maintain eye-safety, even for the aided eye, the airspeed was about 55 kts for the helicopter and 75 kts for the aircraft. The helicopter was used in the alpine regions while the fixed wing aircraft was used in the plains and the urban area, using appropriate scan rates to receive evenly distributed point clouds. The resulting point density ranged from 10 to 25 points per square meter. By carefully selecting days with optimum water quality, satisfactory penetration down to the river bed was achieved

  17. Quantifying and containing the curse of high resolution coronal imaging

    Directory of Open Access Journals (Sweden)

    V. Delouille

    2008-10-01

    Full Text Available Future missions such as Solar Orbiter (SO, InterHelioprobe, or Solar Probe aim at approaching the Sun closer than ever before, with on board some high resolution imagers (HRI having a subsecond cadence and a pixel area of about (80 km2 at the Sun during perihelion. In order to guarantee their scientific success, it is necessary to evaluate if the photon counts available at these resolution and cadence will provide a sufficient signal-to-noise ratio (SNR. For example, if the inhomogeneities in the Quiet Sun emission prevail at higher resolution, one may hope to locally have more photon counts than in the case of a uniform source. It is relevant to quantify how inhomogeneous the quiet corona will be for a pixel pitch that is about 20 times smaller than in the case of SoHO/EIT, and 5 times smaller than TRACE. We perform a first step in this direction by analyzing and characterizing the spatial intermittency of Quiet Sun images thanks to a multifractal analysis. We identify the parameters that specify the scale-invariance behavior. This identification allows next to select a family of multifractal processes, namely the Compound Poisson Cascades, that can synthesize artificial images having some of the scale-invariance properties observed on the recorded images. The prevalence of self-similarity in Quiet Sun coronal images makes it relevant to study the ratio between the SNR present at SoHO/EIT images and in coarsened images. SoHO/EIT images thus play the role of "high resolution" images, whereas the "low-resolution" coarsened images are rebinned so as to simulate a smaller angular resolution and/or a larger distance to the Sun. For a fixed difference in angular resolution and in Spacecraft-Sun distance, we determine the proportion of pixels having a SNR preserved at high resolution given a particular increase in effective area. If scale-invariance continues to prevail at smaller scales, the conclusion reached with SoHO/EIT images can be transposed

  18. High resolution time integration for SN radiation transport

    International Nuclear Information System (INIS)

    Thoreson, Greg; McClarren, Ryan G.; Chang, Jae H.

    2009-01-01

    First-order, second-order, and high resolution time discretization schemes are implemented and studied for the discrete ordinates (S N ) equations. The high resolution method employs a rate of convergence better than first-order, but also suppresses artificial oscillations introduced by second-order schemes in hyperbolic partial differential equations. The high resolution method achieves these properties by nonlinearly adapting the time stencil to use a first-order method in regions where oscillations could be created. We employ a quasi-linear solution scheme to solve the nonlinear equations that arise from the high resolution method. All three methods were compared for accuracy and convergence rates. For non-absorbing problems, both second-order and high resolution converged to the same solution as the first-order with better convergence rates. High resolution is more accurate than first-order and matches or exceeds the second-order method

  19. A high resolution solar atlas for fluorescence calculations

    Science.gov (United States)

    Hearn, M. F.; Ohlmacher, J. T.; Schleicher, D. G.

    1983-01-01

    The characteristics required of a solar atlas to be used for studying the fluorescence process in comets are examined. Several sources of low resolution data were combined to provide an absolutely calibrated spectrum from 2250 A to 7000A. Three different sources of high resolution data were also used to cover this same spectral range. The low resolution data were then used to put each high resolution spectrum on an absolute scale. The three high resolution spectra were then combined in their overlap regions to produce a single, absolutely calibrated high resolution spectrum over the entire spectral range.

  20. High resolution time integration for Sn radiation transport

    International Nuclear Information System (INIS)

    Thoreson, Greg; McClarren, Ryan G.; Chang, Jae H.

    2008-01-01

    First order, second order and high resolution time discretization schemes are implemented and studied for the S n equations. The high resolution method employs a rate of convergence better than first order, but also suppresses artificial oscillations introduced by second order schemes in hyperbolic differential equations. All three methods were compared for accuracy and convergence rates. For non-absorbing problems, both second order and high resolution converged to the same solution as the first order with better convergence rates. High resolution is more accurate than first order and matches or exceeds the second order method. (authors)

  1. Recording of X-ray diffraction patterns for the investigation of transient changes in the crystalline structure of materials subjected to the action of shock waves

    International Nuclear Information System (INIS)

    Jamet, F.; Thomer, G.

    An arrangement including a flash X-ray tube and an image intensifier has been designed and built in order to record X-ray diffraction patterns with exposure times of the order of 100nsec. This arrangement allows Laue patterns (polychromatic radiation) as well as powder patterns (copper K(α) radiation) to be recorded. Examples for record are shown. As an application to the investigation of transient changes in crystalline structures, the Debye-Scherrer patterns of potassium chloride undergoing the dynamic action of shock waves were recorded. The first results achieved are discussed [fr

  2. Understanding reconstructed Dante spectra using high resolution spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    May, M. J., E-mail: may13@llnl.gov; Widmann, K.; Kemp, G. E.; Thorn, D.; Colvin, J. D.; Schneider, M. B.; Moore, A.; Blue, B. E. [L-170 Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94551 (United States); Weaver, J. [Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375 (United States)

    2016-11-15

    The Dante is an 18 channel filtered diode array used at the National Ignition Facility (NIF) to measure the spectrally and temporally resolved radiation flux between 50 eV and 20 keV from various targets. The absolute flux is determined from the radiometric calibration of the x-ray diodes, filters, and mirrors and a reconstruction algorithm applied to the recorded voltages from each channel. The reconstructed spectra are very low resolution with features consistent with the instrument response and are not necessarily consistent with the spectral emission features from the plasma. Errors may exist between the reconstructed spectra and the actual emission features due to assumptions in the algorithm. Recently, a high resolution convex crystal spectrometer, VIRGIL, has been installed at NIF with the same line of sight as the Dante. Spectra from L-shell Ag and Xe have been recorded by both VIRGIL and Dante. Comparisons of these two spectroscopic measurements yield insights into the accuracy of the Dante reconstructions.

  3. Ultra high resolution soft x-ray tomography

    International Nuclear Information System (INIS)

    Haddad, W.S.; Trebes, J.E.; Goodman, D.M.; Lee, H.R.; McNulty, I.; Zalensky, A.O.

    1995-01-01

    Ultra high resolution three dimensional images of a microscopic test object were made with soft x-rays using a scanning transmission x-ray microscope. The test object consisted of two different patterns of gold bars on silicon nitride windows that were separated by ∼5 microm. A series of nine 2-D images of the object were recorded at angles between -50 to +55 degrees with respect to the beam axis. The projections were then combined tomographically to form a 3-D image by means of an algebraic reconstruction technique (ART) algorithm. A transverse resolution of ∼ 1,000 angstrom was observed. Artifacts in the reconstruction limited the overall depth resolution to ∼ 6,000 angstrom, however some features were clearly reconstructed with a depth resolution of ∼ 1,000 angstrom. A specially modified ART algorithm and a constrained conjugate gradient (CCG) code were also developed as improvements over the standard ART algorithm. Both of these methods made significant improvements in the overall depth resolution, bringing it down to ∼ 1,200 angstrom overall. Preliminary projection data sets were also recorded with both dry and re-hydrated human sperm cells over a similar angular range

  4. Ultra high resolution soft x-ray tomography

    International Nuclear Information System (INIS)

    Haddad, W.S.; Trebes, J.E.; Goodman, D.M.

    1995-01-01

    Ultra high resolution three dimensional images of a microscopic test object were made with soft x-rays using a scanning transmission x-ray microscope. The test object consisted of two different patterns of gold bars on silicon nitride windows that were separated by ∼5μm. A series of nine 2-D images of the object were recorded at angles between -50 to +55 degrees with respect to the beam axis. The projections were then combined tomographically to form a 3-D image by means of an algebraic reconstruction technique (ART) algorithm. A transverse resolution of ∼1000 Angstrom was observed. Artifacts in the reconstruction limited the overall depth resolution to ∼6000 Angstrom, however some features were clearly reconstructed with a depth resolution of ∼1000 Angstrom. A specially modified ART algorithm and a constrained conjugate gradient (CCG) code were also developed as improvements over the standard ART algorithm. Both of these methods made significant improvements in the overall depth resolution bringing it down to ∼1200 Angstrom overall. Preliminary projection data sets were also recorded with both dry and re-hydrated human sperm cells over a similar angular range

  5. High-resolution radon monitoring and hydrodynamics at Mount Vesuvius

    Science.gov (United States)

    Cigolini, Corrado; Salierno, Francesco; Gervino, Gianpiero; Bergese, Paolo; Marino, Ciro; Russo, Massimo; Prati, Paolo; Ariola, Vincenzo; Bonetti, Roberto; Begnini, Stefania

    A yearlong high-resolution radon survey has been carried on at Mount Vesuvius, starting in May 1998. Radon activities were acquired by exposing charcoal canisters and track-etch detectors. Sampling stations were deployed along two major summit faults and around the caldera bottom. Volcanically-related earthquakes, with MD ≥ 2.5, may be discriminated from regional seismic events since their cumulative radon anomalies are recorded from stations located along all the above structural features. On the contrary, radon anomalies correlated to regional earthquakes, with MD ≥ 4, are essentially recorded by the sampling sites located along the two summit faults (whose roots extend deeper into the Tertiary basement rocks that underlay the volcano). Radon migration to the surface is ruled by convection within a porous medium of relatively low porosity (ϕ ≈ 10-5), suggesting that fluid motion is strongly localised along fractures. It is suggested that fluid pressure build up, followed by fluid release and migration during incipient fracturing of the porous medium, precede the onset of volcanically-induced earthquakes.

  6. High-resolution EELS investigation of the electronic structure of ilmenites

    NARCIS (Netherlands)

    Radtke, G.; Lazar, S.; Botton, G.A.

    2006-01-01

    The electronic structure of a series of compounds belonging to the ilmenite family is investigated using high resolution electron energy loss spectroscopy (EELS). The energy loss near edge structure (ELNES) of the O-K, Ti-L23 and transition metal L23 edges have been recorded in MnTiO3, FeTiO3,

  7. High-resolution gas-phase spectroscopy of a single-bond axle rotary motor

    NARCIS (Netherlands)

    Maltseva, Elena; Amirjalayer, Saeed; Cnossen, Arjen; Browne, Wesley R.; Feringa, Ben L.; Buma, Wybren Jan

    2017-01-01

    High-resolution laser spectroscopy in combination with molecular beams and mass-spectrometry has been applied to study samples of a prototypical rotary motor. Vibrationally well-resolved excitation spectra have been recorded that are assigned, however, to a structural isomer of the original rotary

  8. High-resolution stratigraphy with strontium isotopes.

    Science.gov (United States)

    Depaolo, D J; Ingram, B L

    1985-02-22

    The isotopic ratio of strontium-87 to strontium-86 shows no detectable variation in present-day ocean water but changes slowly over millions of years. The strontium contained in carbonate shells of marine organisms records the ratio of strontium-87 to strontium-86 of the oceans at the time that the shells form. Sedimentary rocks composed of accumulated fossil carbonate shells can be dated and correlated with the use of high precision measurements of the ratio of strontium-87 to strontium-86 with a resolution that is similar to that of other techniques used in age correlation. This method may prove valuable for many geological, paleontological, paleooceanographic, and geochemical problems.

  9. Scalable Algorithms for Large High-Resolution Terrain Data

    DEFF Research Database (Denmark)

    Mølhave, Thomas; Agarwal, Pankaj K.; Arge, Lars Allan

    2010-01-01

    In this paper we demonstrate that the technology required to perform typical GIS computations on very large high-resolution terrain models has matured enough to be ready for use by practitioners. We also demonstrate the impact that high-resolution data has on common problems. To our knowledge, so...

  10. High-resolution X-ray diffraction studies of multilayers

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Hornstrup, Allan; Schnopper, H. W.

    1988-01-01

    High-resolution X-ray diffraction studies of the perfection of state-of-the-art multilayers are presented. Data were obtained using a triple-axis perfect-crystal X-ray diffractometer. Measurements reveal large-scale figure errors in the substrate. A high-resolution triple-axis set up is required...

  11. Achieving sensitive, high-resolution laser spectroscopy at CRIS

    Energy Technology Data Exchange (ETDEWEB)

    Groote, R. P. de [Instituut voor Kern- en Stralingsfysica, KU Leuven (Belgium); Lynch, K. M., E-mail: kara.marie.lynch@cern.ch [EP Department, CERN, ISOLDE (Switzerland); Wilkins, S. G. [The University of Manchester, School of Physics and Astronomy (United Kingdom); Collaboration: the CRIS collaboration

    2017-11-15

    The Collinear Resonance Ionization Spectroscopy (CRIS) experiment, located at the ISOLDE facility, has recently performed high-resolution laser spectroscopy, with linewidths down to 20 MHz. In this article, we present the modifications to the beam line and the newly-installed laser systems that have made sensitive, high-resolution measurements possible. Highlights of recent experimental campaigns are presented.

  12. High resolution UV spectroscopy and laser-focused nanofabrication

    NARCIS (Netherlands)

    Myszkiewicz, G.

    2005-01-01

    This thesis combines two at first glance different techniques: High Resolution Laser Induced Fluorescence Spectroscopy (LIF) of small aromatic molecules and Laser Focusing of atoms for Nanofabrication. The thesis starts with the introduction to the high resolution LIF technique of small aromatic

  13. Very high resolution UV and X-ray spectroscopy and imagery of solar active regions

    Science.gov (United States)

    Bruner, M.; Brown, W. A.; Haisch, B. M.

    1987-01-01

    A scientific investigation of the physics of the solar atmosphere, which uses the techniques of high resolution soft X-ray spectroscopy and high resolution UV imagery, is described. The experiments were conducted during a series of three sounding rocket flights. All three flights yielded excellent images in the UV range, showing unprecedented spatial resolution. The second flight recorded the X-ray spectrum of a solar flare, and the third that of an active region. A normal incidence multi-layer mirror was used during the third flight to make the first astronomical X-ray observations using this new technique.

  14. DNA oligonucleotide conformations: high resolution NMR studies

    International Nuclear Information System (INIS)

    Mellema, J.-R.

    1984-01-01

    The present work describes a DNA double-helix model, which is well comparable with the models derived from fibre-diffraction studies. The model has a mononucleotide repeat with torsion angles in accordance with average geometries as derived from 1 H NMR studies. Special attention was paid to reduce the number of short H-H nonbonding contacts, which are abundantly present in the 'classical' fibre-diffraction models. Chapter 3 describes the first complete assignment of a 1 H NMR spectrum of a DNA tetramer, d(TAAT). Preliminary conformational data derived from the spectral parameters recorded at 27 0 C are given. A more detailed analysis employing temperature-dependence studies is given in Chapter 4. (Auth.)

  15. High resolution imaging detectors and applications

    CERN Document Server

    Saha, Swapan K

    2015-01-01

    Interferometric observations need snapshots of very high time resolution of the order of (i) frame integration of about 100 Hz or (ii) photon-recording rates of several megahertz (MHz). Detectors play a key role in astronomical observations, and since the explanation of the photoelectric effect by Albert Einstein, the technology has evolved rather fast. The present-day technology has made it possible to develop large-format complementary metal oxide–semiconductor (CMOS) and charge-coupled device (CCD) array mosaics, orthogonal transfer CCDs, electron-multiplication CCDs, electron-avalanche photodiode arrays, and quantum-well infrared (IR) photon detectors. The requirements to develop artifact-free photon shot noise-limited images are higher sensitivity and quantum efficiency, reduced noise that includes dark current, read-out and amplifier noise, smaller point-spread functions, and higher spectral bandwidth. This book aims to address such systems, technologies and design, evaluation and calibration, control...

  16. High resolution NMR spectroscopy of synthetic polymers in bulk

    International Nuclear Information System (INIS)

    Komorski, R.A.

    1986-01-01

    The contents of this book are: Overview of high-resolution NMR of solid polymers; High-resolution NMR of glassy amorphous polymers; Carbon-13 solid-state NMR of semicrystalline polymers; Conformational analysis of polymers of solid-state NMR; High-resolution NMR studies of oriented polymers; High-resolution solid-state NMR of protons in polymers; and Deuterium NMR of solid polymers. This work brings together the various approaches for high-resolution NMR studies of bulk polymers into one volume. Heavy emphasis is, of course, given to 13C NMR studies both above and below Tg. Standard high-power pulse and wide-line techniques are not covered

  17. Development of high resolution vacuum ultraviolet beam line at Indus-1 synchrotron source

    International Nuclear Information System (INIS)

    Shukla, R.P.; Das, N.C.; Udupa, D.V.; Saraswathy, P.; Sunanda, K.; Jha, S.N.; Shastri, Aparna; Singh, Paramjeet; Mallick, Manika; Mishra, A.P.; Sahoo, N.K.; Sinha, A.K.; Bhatt, S.; Sahni, V.C.

    2005-07-01

    High resolution vacuum ultraviolet beamline at Indus-1 450 MeV synchrotron source has been developed for carrying out absorption spectral studies of atoms and molecules. The beamline consists of three major parts i.e. a focusing optical system, an absorption cell and a high resolution 6.65 m vacuum ultraviolet spectrometer in Eagle mount. The wavelength range of the spectrometer is from 700 A to 2000 A and the resolution of the spectrometer is 0.01 A. Using the synchrotron source Indus-1, the absorption spectra of oxygen, ammonia and carbon disulphide have been recorded at the wavelength band of 1750 A, 1881 A and 3100 A respectively. Details of different aspects of design and development of the high resolution VUV beamline are described in this report. (author)

  18. Clickstream Data Yields High-Resolution Maps of Science

    Science.gov (United States)

    Bollen, Johan; Van de Sompel, Herbert; Rodriguez, Marko A.; Balakireva, Lyudmila

    2009-01-01

    Background Intricate maps of science have been created from citation data to visualize the structure of scientific activity. However, most scientific publications are now accessed online. Scholarly web portals record detailed log data at a scale that exceeds the number of all existing citations combined. Such log data is recorded immediately upon publication and keeps track of the sequences of user requests (clickstreams) that are issued by a variety of users across many different domains. Given these advantages of log datasets over citation data, we investigate whether they can produce high-resolution, more current maps of science. Methodology Over the course of 2007 and 2008, we collected nearly 1 billion user interactions recorded by the scholarly web portals of some of the most significant publishers, aggregators and institutional consortia. The resulting reference data set covers a significant part of world-wide use of scholarly web portals in 2006, and provides a balanced coverage of the humanities, social sciences, and natural sciences. A journal clickstream model, i.e. a first-order Markov chain, was extracted from the sequences of user interactions in the logs. The clickstream model was validated by comparing it to the Getty Research Institute's Architecture and Art Thesaurus. The resulting model was visualized as a journal network that outlines the relationships between various scientific domains and clarifies the connection of the social sciences and humanities to the natural sciences. Conclusions Maps of science resulting from large-scale clickstream data provide a detailed, contemporary view of scientific activity and correct the underrepresentation of the social sciences and humanities that is commonly found in citation data. PMID:19277205

  19. Clickstream data yields high-resolution maps of science.

    Science.gov (United States)

    Bollen, Johan; Van de Sompel, Herbert; Hagberg, Aric; Bettencourt, Luis; Chute, Ryan; Rodriguez, Marko A; Balakireva, Lyudmila

    2009-01-01

    Intricate maps of science have been created from citation data to visualize the structure of scientific activity. However, most scientific publications are now accessed online. Scholarly web portals record detailed log data at a scale that exceeds the number of all existing citations combined. Such log data is recorded immediately upon publication and keeps track of the sequences of user requests (clickstreams) that are issued by a variety of users across many different domains. Given these advantages of log datasets over citation data, we investigate whether they can produce high-resolution, more current maps of science. Over the course of 2007 and 2008, we collected nearly 1 billion user interactions recorded by the scholarly web portals of some of the most significant publishers, aggregators and institutional consortia. The resulting reference data set covers a significant part of world-wide use of scholarly web portals in 2006, and provides a balanced coverage of the humanities, social sciences, and natural sciences. A journal clickstream model, i.e. a first-order Markov chain, was extracted from the sequences of user interactions in the logs. The clickstream model was validated by comparing it to the Getty Research Institute's Architecture and Art Thesaurus. The resulting model was visualized as a journal network that outlines the relationships between various scientific domains and clarifies the connection of the social sciences and humanities to the natural sciences. Maps of science resulting from large-scale clickstream data provide a detailed, contemporary view of scientific activity and correct the underrepresentation of the social sciences and humanities that is commonly found in citation data.

  20. Scottish Sea Lochs: High Resolution Archives of North Atlantic Climate

    Science.gov (United States)

    Norgaard-Pedersen, N.; Austin, W. E.; Cage, A. G.; Shimmield, T. M.; Gillibrand, P. A.

    2002-12-01

    The sea lochs (fjords) of NW Scotland bridge the land-ocean interface in a region of Europe which is particularly well situated to monitor changes in westerly air flow. Inter-annual atmospheric circulation changes at this latitude are largely governed by the North Atlantic Oscillation (NAO), in turn influencing both westerlies and precipitation. Comparing two extreme recent NAO years, circulation modelling results from Loch Sunart, NW Scotland, reveal a clear response to freshwater runoff and wind forcing in both magnitude and rate of deep-water renewal events. Scottish fjords, because of the relatively small impact which salinity has on d18Owater (0.18 % per salinity unit), potentially provide NW Europe's most useful study sites in coastal palaeoclimate research, particularly where palaeotemperature is the primary record of interest. New data from a high-resolution record (7 yr sample resolution), spanning the last two millennia, from the deepest part of the main basin of Loch Sunart illustrate significant multi-decadal to centennial scale variability in the sedimentary and stable isotope record of epibenthic foraminifera Cibicides lobatulus. The long-term pattern in benthic d18O appears to reflect bottom water temperature differences of 1-2§C, resolving climatic periods such as the Medieval Warm Period and the Little Ice Age. Since the core site is connected with shelf waters (i.e. no shallow sill) it seems likely that this paleotemperature reflects changing shelf water, not the exchange process as a function of long-term runoff/wind forcing. Grain size data and XRF data point to catchment-wide responses (weathering and erosion) which appear to show the largest variability during the last millennium, driven either by rainfall and temperature and/or land-use. Pb-isotope data, constraining the modern and industrial period, suggest accelerated sedimentation rates over this interval. On-going work attempts to calibrate proxy data with instrumental historical data.

  1. Clickstream data yields high-resolution maps of science.

    Directory of Open Access Journals (Sweden)

    Johan Bollen

    Full Text Available BACKGROUND: Intricate maps of science have been created from citation data to visualize the structure of scientific activity. However, most scientific publications are now accessed online. Scholarly web portals record detailed log data at a scale that exceeds the number of all existing citations combined. Such log data is recorded immediately upon publication and keeps track of the sequences of user requests (clickstreams that are issued by a variety of users across many different domains. Given these advantages of log datasets over citation data, we investigate whether they can produce high-resolution, more current maps of science. METHODOLOGY: Over the course of 2007 and 2008, we collected nearly 1 billion user interactions recorded by the scholarly web portals of some of the most significant publishers, aggregators and institutional consortia. The resulting reference data set covers a significant part of world-wide use of scholarly web portals in 2006, and provides a balanced coverage of the humanities, social sciences, and natural sciences. A journal clickstream model, i.e. a first-order Markov chain, was extracted from the sequences of user interactions in the logs. The clickstream model was validated by comparing it to the Getty Research Institute's Architecture and Art Thesaurus. The resulting model was visualized as a journal network that outlines the relationships between various scientific domains and clarifies the connection of the social sciences and humanities to the natural sciences. CONCLUSIONS: Maps of science resulting from large-scale clickstream data provide a detailed, contemporary view of scientific activity and correct the underrepresentation of the social sciences and humanities that is commonly found in citation data.

  2. High resolution transmission imaging without lenses

    International Nuclear Information System (INIS)

    Rodenburg, J M; Hurst, A C; Maiden, A

    2010-01-01

    The whole history of transmission imaging has been dominated by the lens, whether used in visible-light optics, electron optics or X-ray optics. Lenses can be thought of as a very efficient method of processing a wave front scattered from an object into an image of that object. An alternative approach is to undertake this image-formation process using a computational technique. The crudest scattering experiment is to simply record the intensity of a diffraction pattern. Recent progress in so-called diffractive imaging has shown that it is possible to recover the phase of a scattered wavefield from its diffraction pattern alone, as long as the object (or the illumination on the object) is of finite extent. In this paper we present results from a very efficient phase retrieval method which can image infinitely large fields of view. It may have important applications in improving resolution in electron microscopy, or at least allowing low specification microscopes to achieve resolution comparable to state-of-the-art machines.

  3. Cheetah: A high frame rate, high resolution SWIR image camera

    Science.gov (United States)

    Neys, Joel; Bentell, Jonas; O'Grady, Matt; Vermeiren, Jan; Colin, Thierry; Hooylaerts, Peter; Grietens, Bob

    2008-10-01

    A high resolution, high frame rate InGaAs based image sensor and associated camera has been developed. The sensor and the camera are capable of recording and delivering more than 1700 full 640x512pixel frames per second. The FPA utilizes a low lag CTIA current integrator in each pixel, enabling integration times shorter than one microsecond. On-chip logics allows for four different sub windows to be read out simultaneously at even higher rates. The spectral sensitivity of the FPA is situated in the SWIR range [0.9-1.7 μm] and can be further extended into the Visible and NIR range. The Cheetah camera has max 16 GB of on-board memory to store the acquired images and transfer the data over a Gigabit Ethernet connection to the PC. The camera is also equipped with a full CameralinkTM interface to directly stream the data to a frame grabber or dedicated image processing unit. The Cheetah camera is completely under software control.

  4. High-resolution seismic reflection surveying with a land streamer

    Science.gov (United States)

    Cengiz Tapırdamaz, Mustafa; Cankurtaranlar, Ali; Ergintav, Semih; Kurt, Levent

    2013-04-01

    In this study, newly designed seismic reflection data acquisition array (land streamer) is utilized to image the shallow subsurface. Our acquisition system consist of 24 geophones screwed on iron plates with 2 m spacing, moving on the surface of the earth which are connected with fire hose. Completely original, 4.5 Kg weight iron plates provides satisfactory coupling. This land-streamer system enables rapid and cost effective acquisition of seismic reflection data due to its operational facilities. First test studies were performed using various seismic sources such as a mini-vibro truck, buffalo-gun and hammer. The final fieldwork was performed on a landslide area which was studied before. Data acquisition was carried out on the line that was previously measured by the seismic survey using 5 m geophone and shot spacing. This line was chosen in order to re-image known reflection patterns obtained from the previous field study. Taking penetration depth into consideration, a six-cartridge buffalo-gun was selected as a seismic source to achieve high vertical resolution. Each shot-point drilled 50 cm for gunshots to obtain high resolution source signature. In order to avoid surface waves, the offset distance between the source and the first channel was chosen to be 50 m and the shot spacing was 2 m. These acquisition parameters provided 12 folds at each CDP points. Spatial sampling interval was 1 m at the surface. The processing steps included standard stages such as gain recovery, editing, frequency filtering, CDP sorting, NMO correction, static correction and stacking. Furthermore, surface consistent residual static corrections were applied recursively to improve image quality. 2D F-K filter application was performed to suppress air and surface waves at relatively deep part of the seismic section. Results show that, this newly designed, high-resolution land seismic data acquisition equipment (land-streamer) can be successfully used to image subsurface. Likewise

  5. High-resolution esophageal pressure topography for esophageal motility disorders

    Directory of Open Access Journals (Sweden)

    Hashem Fakhre Yaseri

    2016-04-01

    Full Text Available Background: High-resolution manometer (HRM of the esophagus has become the main diagnostic test in the evaluation of esophageal motility disorders. The development of high-resolution manometry catheters and software displays of manometry recordings in color-coded pressure plots have changed the diagnostic assessment of esophageal disease. The first step of the Chicago classification described abnormal esophagogastric junction deglutitive relaxation. The latest classification system, proposed by Pandolfino et al, includes contraction patterns and peristalsis integrity based on integrated relaxation pressure 4 (IRP4. It can be discriminating the achalasia from non-achalasia esophageal motility disorders. The aim of this study was to assessment of clinical findings in non-achalasia esophageal motility disorders based on the most recent Chicago classification. Methods: We conducted a prospective cross-sectional study of 963 patients that had been referred to manometry department of Gastrointestinal and Liver Research Center, Firozgar Hospital, Tehran, Iran, from April, 2012 to April, 2015. They had upper GI disorder (Dysphasia, non-cardiac chest pain, regurgitation, heartburn, vomiting and asthma and weight loss. Data were collected from clinical examinations as well as patient questionnaires. Manometry, water-perfused, was done for all patients. Manometry criteria of the patients who had integrated relaxation pressure 4 (IRP4 ≤ 15 mmHg were studied. Results: Our finding showed that the non-achalasia esophageal motility disorders (58% was more common than the achalasia (18.2%. Heartburn (68.5%, regurgitation (65.4% and non-cardiac chest pain (60.6% were the most common clinical symptoms. Although, vomiting (91.7% and weight loss (63% were the most common symptoms in referring patients but did not discriminate this disorders from each other’s. Borderline motor function (67.2% was the most common, absent peristalsis (97% and the hyper

  6. High-resolution seismic reflection study, Vacherie Dome

    International Nuclear Information System (INIS)

    1984-06-01

    A high-resolution seismic reflection study, consisting of recording, processing, and interpreting four seismic reflection lines, was made at Vacherie Dome, Louisiana. The presumed shape of the dome, as pictured in the geologic area characterization report by Law Engineering Testing Company in 1982, was based largely on interpretation of gravity data, constrained by a few wells and exploration-type seismic profiles. The purpose of the study was to obtain refined profiles of the dome above -914 m (-3000 ft) elevation. Additional study had been recommended by Louisiana State University in 1967 and the Office of Nuclear Waste Isolation in 1981 because the interpreted size of Vacherie Dome was based on limited seismic and gravity data. Forty-eight traces of seismic data were recorded each time shots were made to generate energy. Twelve-fold, common-depth-point data were obtained using geophone stations spaced at 15-m (50-ft) intervals with shots at 30-m (100-ft) intervals. The time-sampling interval used was 1 ms. Processing intended to enhance resolution included iterative static corrections, deconvolution before stacking, and both time- and depth-migration. The locations of the steep dome sides were inferred primarily from terminations of strong reflections (migrated) from strata near the top of the upper and lower Cretaceous sections. This interpretation agrees closely with the presumed shape from the top of the dome to about -610 m (-2000 ft) elevation, but below this on three of the profiles, this interpretation indicates a steeper salt face than the presumed shape. The area reduction at -914 m (-3000 ft) elevation is estimated to be on the order of 20 percent. 10 references, 11 figures, 4 tables

  7. A Forward-Looking High-Resolution GPR System

    National Research Council Canada - National Science Library

    Kositsky, Joel; Milanfar, Peyman

    1999-01-01

    A high-resolution ground penetrating radar (GPR) system was designed to help define the optimal radar parameters needed for the efficient standoff detection of buried and surface-laid antitank mines...

  8. High-resolution seismic wave propagation using local time stepping

    KAUST Repository

    Peter, Daniel; Rietmann, Max; Galvez, Percy; Ampuero, Jean Paul

    2017-01-01

    High-resolution seismic wave simulations often require local refinements in numerical meshes to accurately capture e.g. steep topography or complex fault geometry. Together with explicit time schemes, this dramatically reduces the global time step

  9. Impact of high resolution land surface initialization in Indian summer ...

    Indian Academy of Sciences (India)

    The direct impact of high resolution land surface initialization on the forecast bias in a regional climate model in recent years ... surface initialization using a regional climate model. ...... ization of the snow field in a cloud model; J. Clim. Appl.

  10. Textural Segmentation of High-Resolution Sidescan Sonar Images

    National Research Council Canada - National Science Library

    Kalcic, Maria; Bibee, Dale

    1995-01-01

    .... The high resolution of the 455 kHz sonar imagery also provides much information about the surficial bottom sediments, however their acoustic scattering properties are not well understood at high frequencies...

  11. NOAA High-Resolution Sea Surface Temperature (SST) Analysis Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archive covers two high resolution sea surface temperature (SST) analysis products developed using an optimum interpolation (OI) technique. The analyses have a...

  12. Hurricane Satellite (HURSAT) from Advanced Very High Resolution Radiometer (AVHRR)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Huricane Satellite (HURSAT)-Advanced Very High Resolution Radiometer (AVHRR) is used to extend the HURSAT data set such that appling the Objective Dvorak technique...

  13. NanoComposite Polymers for High Resolution Near Infrared Detectors

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop nanocomposite materials with tuned refractive index in the near infra red spectral range as an index-matched immersion lens for high resolution infra-red...

  14. High resolution integral holography using Fourier ptychographic approach.

    Science.gov (United States)

    Li, Zhaohui; Zhang, Jianqi; Wang, Xiaorui; Liu, Delian

    2014-12-29

    An innovative approach is proposed for calculating high resolution computer generated integral holograms by using the Fourier Ptychographic (FP) algorithm. The approach initializes a high resolution complex hologram with a random guess, and then stitches together low resolution multi-view images, synthesized from the elemental images captured by integral imaging (II), to recover the high resolution hologram through an iterative retrieval with FP constrains. This paper begins with an analysis of the principle of hologram synthesis from multi-projections, followed by an accurate determination of the constrains required in the Fourier ptychographic integral-holography (FPIH). Next, the procedure of the approach is described in detail. Finally, optical reconstructions are performed and the results are demonstrated. Theoretical analysis and experiments show that our proposed approach can reconstruct 3D scenes with high resolution.

  15. High-resolution MRI in detecting subareolar breast abscess.

    Science.gov (United States)

    Fu, Peifen; Kurihara, Yasuyuki; Kanemaki, Yoshihide; Okamoto, Kyoko; Nakajima, Yasuo; Fukuda, Mamoru; Maeda, Ichiro

    2007-06-01

    Because subareolar breast abscess has a high recurrence rate, a more effective imaging technique is needed to comprehensively visualize the lesions and guide surgery. We performed a high-resolution MRI technique using a microscopy coil to reveal the characteristics and extent of subareolar breast abscess. High-resolution MRI has potential diagnostic value in subareolar breast abscess. This technique can be used to guide surgery with the aim of reducing the recurrence rate.

  16. Volumetric expiratory high-resolution CT of the lung

    International Nuclear Information System (INIS)

    Nishino, Mizuki; Hatabu, Hiroto

    2004-01-01

    We developed a volumetric expiratory high-resolution CT (HRCT) protocol that provides combined inspiratory and expiratory volumetric imaging of the lung without increasing radiation exposure, and conducted a preliminary feasibility assessment of this protocol to evaluate diffuse lung disease with small airway abnormalities. The volumetric expiratory high-resolution CT increased the detectability of the conducting airway to the areas of air trapping (P<0.0001), and added significant information about extent and distribution of air trapping (P<0.0001)

  17. Developing Visual Editors for High-Resolution Haptic Patterns

    DEFF Research Database (Denmark)

    Cuartielles, David; Göransson, Andreas; Olsson, Tony

    2012-01-01

    In this article we give an overview of our iterative work in developing visual editors for creating high resolution haptic patterns to be used in wearable, haptic feedback devices. During the past four years we have found the need to address the question of how to represent, construct and edit high...... resolution haptic patterns so that they translate naturally to the user’s haptic experience. To solve this question we have developed and tested several visual editors...

  18. EMODnet High Resolution Seabed Mapping - further developing a high resolution digital bathymetry for European seas

    Science.gov (United States)

    Schaap, D.; Schmitt, T.

    2017-12-01

    Access to marine data is a key issue for the EU Marine Strategy Framework Directive and the EU Marine Knowledge 2020 agenda and includes the European Marine Observation and Data Network (EMODnet) initiative. EMODnet aims at assembling European marine data, data products and metadata from diverse sources in a uniform way. The EMODnet Bathymetry project has developed Digital Terrain Models (DTM) for the European seas. These have been produced from survey and aggregated data sets that are indexed with metadata by adopting the SeaDataNet Catalogue services. SeaDataNet is a network of major oceanographic data centres around the European seas that manage, operate and further develop a pan-European infrastructure for marine and ocean data management. The latest EMODnet Bathymetry DTM release has a grid resolution of 1/8 arcminute and covers all European sea regions. Use has been made of circa 7800 gathered survey datasets and composite DTMs. Catalogues and the EMODnet DTM are published at the dedicated EMODnet Bathymetry portal including a versatile DTM viewing and downloading service. End December 2016 the Bathymetry project has been succeeded by EMODnet High Resolution Seabed Mapping (HRSM). This continues gathering of bathymetric in-situ data sets with extra efforts for near coastal waters and coastal zones. In addition Satellite Derived Bathymetry data are included to fill gaps in coverage of the coastal zones. The extra data and composite DTMs will increase the coverage of the European seas and its coastlines, and provide input for producing an EMODnet DTM with a common resolution of 1/16 arc minutes. The Bathymetry Viewing and Download service will be upgraded to provide a multi-resolution map and including 3D viewing. The higher resolution DTMs will also be used to determine best-estimates of the European coastline for a range of tidal levels (HAT, MHW, MSL, Chart Datum, LAT), thereby making use of a tidal model for Europe. Extra challenges will be `moving to the

  19. Accelerated high-resolution photoacoustic tomography via compressed sensing

    Science.gov (United States)

    Arridge, Simon; Beard, Paul; Betcke, Marta; Cox, Ben; Huynh, Nam; Lucka, Felix; Ogunlade, Olumide; Zhang, Edward

    2016-12-01

    Current 3D photoacoustic tomography (PAT) systems offer either high image quality or high frame rates but are not able to deliver high spatial and temporal resolution simultaneously, which limits their ability to image dynamic processes in living tissue (4D PAT). A particular example is the planar Fabry-Pérot (FP) photoacoustic scanner, which yields high-resolution 3D images but takes several minutes to sequentially map the incident photoacoustic field on the 2D sensor plane, point-by-point. However, as the spatio-temporal complexity of many absorbing tissue structures is rather low, the data recorded in such a conventional, regularly sampled fashion is often highly redundant. We demonstrate that combining model-based, variational image reconstruction methods using spatial sparsity constraints with the development of novel PAT acquisition systems capable of sub-sampling the acoustic wave field can dramatically increase the acquisition speed while maintaining a good spatial resolution: first, we describe and model two general spatial sub-sampling schemes. Then, we discuss how to implement them using the FP interferometer and demonstrate the potential of these novel compressed sensing PAT devices through simulated data from a realistic numerical phantom and through measured data from a dynamic experimental phantom as well as from in vivo experiments. Our results show that images with good spatial resolution and contrast can be obtained from highly sub-sampled PAT data if variational image reconstruction techniques that describe the tissues structures with suitable sparsity-constraints are used. In particular, we examine the use of total variation (TV) regularization enhanced by Bregman iterations. These novel reconstruction strategies offer new opportunities to dramatically increase the acquisition speed of photoacoustic scanners that employ point-by-point sequential scanning as well as reducing the channel count of parallelized schemes that use detector arrays.

  20. A method for generating high resolution satellite image time series

    Science.gov (United States)

    Guo, Tao

    2014-10-01

    There is an increasing demand for satellite remote sensing data with both high spatial and temporal resolution in many applications. But it still is a challenge to simultaneously improve spatial resolution and temporal frequency due to the technical limits of current satellite observation systems. To this end, much R&D efforts have been ongoing for years and lead to some successes roughly in two aspects, one includes super resolution, pan-sharpen etc. methods which can effectively enhance the spatial resolution and generate good visual effects, but hardly preserve spectral signatures and result in inadequate analytical value, on the other hand, time interpolation is a straight forward method to increase temporal frequency, however it increase little informative contents in fact. In this paper we presented a novel method to simulate high resolution time series data by combing low resolution time series data and a very small number of high resolution data only. Our method starts with a pair of high and low resolution data set, and then a spatial registration is done by introducing LDA model to map high and low resolution pixels correspondingly. Afterwards, temporal change information is captured through a comparison of low resolution time series data, and then projected onto the high resolution data plane and assigned to each high resolution pixel according to the predefined temporal change patterns of each type of ground objects. Finally the simulated high resolution data is generated. A preliminary experiment shows that our method can simulate a high resolution data with a reasonable accuracy. The contribution of our method is to enable timely monitoring of temporal changes through analysis of time sequence of low resolution images only, and usage of costly high resolution data can be reduces as much as possible, and it presents a highly effective way to build up an economically operational monitoring solution for agriculture, forest, land use investigation

  1. Diagnostic Yield of Transbronchial Biopsy in Comparison to High Resolution Computerized Tomography in Sarcoidosis Cases

    Science.gov (United States)

    Akten, H Serpil; Kilic, Hatice; Celik, Bulent; Erbas, Gonca; Isikdogan, Zeynep; Turktas, Haluk; Kokturk, Nurdan

    2018-04-25

    This study aimed to evaluate the diagnostic yield of fiberoptic bronchoscopic (FOB) transbronchial biopsy and its relation with quantitative findings of high resolution computerized tomography (HRCT). A total of 83 patients, 19 males and 64 females with a mean age of 45.1 years diagnosed with sarcoidosis with complete records of high resolution computerized tomography were retrospectively recruited during the time period from Feb 2005 to Jan 2015. High resolution computerized tomography scans were retrospectively assessed in random order by an experienced observer without knowledge of the bronchoscopic results or lung function tests. According to the radiological staging with HRCT, 2.4% of the patients (n=2) were stage 0, 19.3% (n=16) were stage 1, 72.3% (n=60) were stage 2 and 6.0% (n=5) were stage 3. This study showed that transbronchial lung biopsy showed positive results in 39.7% of the stage I or II sarcoidosis patients who were diagnosed by bronchoscopy. Different high resolution computerized tomography patterns and different scores of involvement did make a difference in the diagnostic accuracy of transbronchial biopsy (p=0.007). Creative Commons Attribution License

  2. Experimental demonstration of high resolution three-dimensional x-ray holography

    International Nuclear Information System (INIS)

    McNulty, I.; Trebes, J.E.; Brase, J.M.; Yorkey, T.J.; Levesque, R.; Szoke, H.; Anderson, E.H.; Jacobsen, C.

    1992-01-01

    Tomographic x-ray holography may make possible the imaging of biological objects at high resolution in three dimensions. We performed a demonstration experiment with soft x-rays to explore the feasibility of this technique. Coherent 3.2-nm undulator radiation was used to record Fourier transform holograms of a microfabricated test object from various illumination angles. The holograms were numerically reconstructed according to the principles of diffraction tomography, yielding images of the object that are well resolved in three dimensions

  3. High resolution manometry findings in patients with esophageal epiphrenic diverticula.

    Science.gov (United States)

    Vicentine, Fernando P P; Herbella, Fernando A M; Silva, Luciana C; Patti, Marco G

    2011-12-01

    The pathophysiology of esophageal epiphrenic diverticula is still uncertain even though a concomitant motility disorder is found in the majority of patients in different series. High resolution manometry may allow detection of motor abnormalities in a higher number of patients with esophageal epiphrenic diverticula compared with conventional manometry. This study aims to evaluate the high resolution manometry findings in patients with esophageal epiphrenic diverticula. Nine individuals (mean age 63 ± 10 years, 4 females) with esophageal epiphrenic diverticula underwent high resolution manometry. A single diverticulum was observed in eight patients and multiple diverticula in one. Visual analysis of conventional tracings and color pressure plots for identification of segmental abnormalities was performed by two researchers experienced in high resolution manometry. Upper esophageal sphincter was normal in all patients. Esophageal body was abnormal in eight patients; lower esophageal sphincter was abnormal in seven patients. Named esophageal motility disorders were found in seven patients: achalasia in six, diffuse esophageal spasm in one. In one patient, a segmental hypercontractile zone was noticed with pressure of 196 mm Hg. High resolution manometry demonstrated motor abnormalities in all patients with esophageal epiphrenic diverticula.

  4. Time dependent auto-correlation, autospectrum and decay ratio estimation of transient signals in JET soft X-ray records

    International Nuclear Information System (INIS)

    Por, G.

    1999-08-01

    A program package was developed to estimate the time dependent auto-correlation function (ACF) from the time signals of soft X-ray records taken along the various lines-of-sights in JET-SHOTS, and also to estimate the time dependent Decay Ratio (DR) from that. On the basis of ACF the time dependent auto-power spectral density (APSD) was also calculated. The steps and objectives of this work were: eliminating the white detection noise, trends and slow variation from the time signals, since ordinary methods can give good estimate of the time dependent ACF and DR only for 'nearly' stationary signals, developing an automatic algorithm for finding the maxima and minima of ACF, since they are the basis for DR estimation, evaluating and testing different DR estimators for JET-SHOT, with the aim of finding parts of the signals, where the oscillating character is strong, estimating time dependent ACF and APSD that can follow the relatively fast variation in the time signal. The methods that we have developed for data processing of transient signals are: White detection noise removal and preparation for trend removal - weak components, white detection noise and high frequency components are filtered from the signal using the so-called soft-threshold wavelet filter. Removal of trends and slow variation - Three-point differentiation of the pre-filtered signal is used to remove trends and slow variation. Here we made use of the DERIV function of IDL program language. This leads to a filtered signal that has zero mean value in each time step. Calculation of the time dependent ACF - The signal treated by the two previous steps is used as the input. Calculated ACF value is added in each new time step, but the previously accumulated ACF value is multiplied by a weighting factor. Thus the new sample has 100% contribution, while the contributions from the previous samples are forgotten quickly. DR calculation - DR is a measure of the decay of oscillating ACF. This parameter was shown

  5. Compact and high-resolution optical orbital angular momentum sorter

    Directory of Open Access Journals (Sweden)

    Chenhao Wan

    2017-03-01

    Full Text Available A compact and high-resolution optical orbital angular momentum (OAM sorter is proposed and demonstrated. The sorter comprises a quadratic fan-out mapper and a dual-phase corrector positioned in the pupil plane and the Fourier plane, respectively. The optical system is greatly simplified compared to previous demonstrations of OAM sorting, and the performance in resolution and efficiency is maintained. A folded configuration is set up using a single reflective spatial light modulator (SLM to demonstrate the validity of the scheme. The two phase elements are implemented on the left and right halves of the SLM and connected by a right-angle prism. Experimental results demonstrate the high resolution of the compact OAM sorter, and the current limit in efficiency can be overcome by replacing with transmissive SLMs and removing the beam splitters. This novel scheme paves the way for the miniaturization and integration of high-resolution OAM sorters.

  6. High-resolution SPECT for small-animal imaging

    International Nuclear Information System (INIS)

    Qi Yujin

    2006-01-01

    This article presents a brief overview of the development of high-resolution SPECT for small-animal imaging. A pinhole collimator has been used for high-resolution animal SPECT to provide better spatial resolution and detection efficiency in comparison with a parallel-hole collimator. The theory of imaging characteristics of the pinhole collimator is presented and the designs of the pinhole aperture are discussed. The detector technologies used for the development of small-animal SPECT and the recent advances are presented. The evolving trend of small-animal SPECT is toward a multi-pinhole and a multi-detector system to obtain a high resolution and also a high detection efficiency. (authors)

  7. High-resolution spectroscopy of gases for industrial applications

    DEFF Research Database (Denmark)

    Fateev, Alexander; Clausen, Sønnik

    High-resolution spectroscopy of gases is a powerful technique which has various fundamental and practical applications: in situ simultaneous measurements of gas temperature and gas composition, radiative transfer modeling, validation of existing and developing of new databases and etc. Existing...... databases (e.g. HITRAN, HITEMP or CDSD) can normally be used for absorption spectra calculations at limited temperature/pressure ranges. Therefore experimental measurements of absorption/transmission spectra gases (e.g. CO2, H2O or SO2) at high-resolution and elevated temperatures are essential both...... for analysis of complex experimental data and further development of the databases. High-temperature gas cell facilities available at DTU Chemical Engineering are presented and described. The gas cells and high-resolution spectrometers allow us to perform high-quality reference measurements of gases relevant...

  8. 1024 matrix image reconstruction: usefulness in high resolution chest CT

    International Nuclear Information System (INIS)

    Jeong, Sun Young; Chung, Myung Jin; Chong, Se Min; Sung, Yon Mi; Lee, Kyung Soo

    2006-01-01

    We tried to evaluate whether high resolution chest CT with a 1,024 matrix has a significant advantage in image quality compared to a 512 matrix. Each set of 512 and 1024 matrix high resolution chest CT scans with both 0.625 mm and 1.25 mm slice thickness were obtained from 26 patients. Seventy locations that contained twenty-four low density lesions without sharp boundary such as emphysema, and forty-six sharp linear densities such as linear fibrosis were selected; these were randomly displayed on a five mega pixel LCD monitor. All the images were masked for information concerning the matrix size and slice thickness. Two chest radiologists scored the image quality of each ar rowed lesion as follows: (1) undistinguishable, (2) poorly distinguishable, (3) fairly distinguishable, (4) well visible and (5) excellently visible. The scores were compared from the aspects of matrix size, slice thickness and the different observers by using ANOVA tests. The average and standard deviation of image quality were 3.09 (± .92) for the 0.625 mm x 512 matrix, 3.16 (± .84) for the 0.625 mm x 1024 matrix, 2.49 (± 1.02) for the 1.25 mm x 512 matrix, and 2.35 (± 1.02) for the 1.25 mm x 1024 matrix, respectively. The image quality on both matrices of the high resolution chest CT scans with a 0.625 mm slice thickness was significantly better than that on the 1.25 mm slice thickness (ρ < 0.001). However, the image quality on the 1024 matrix high resolution chest CT scans was not significantly different from that on the 512 matrix high resolution chest CT scans (ρ = 0.678). The interobserver variation between the two observers was not significant (ρ = 0.691). We think that 1024 matrix image reconstruction for high resolution chest CT may not be clinical useful

  9. Changes in Moisture Flux over the Tibetan Plateau during 1979-2011: Insights from a High Resolution Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Yanhong; Leung, Lai-Yung R.; Zhang, Yongxin; Cuo, Lan

    2015-05-15

    Net precipitation (precipitation minus evapotranspiration, P-E) changes between 1979 and 2011 from a high resolution regional climate simulation and its reanalysis forcing are analyzed over the Tibet Plateau (TP) and compared to the global land data assimilation system (GLDAS) product. The high resolution simulation better resolves precipitation changes than its coarse resolution forcing, which contributes dominantly to the improved P-E change in the regional simulation compared to the global reanalysis. Hence, the former may provide better insights about the drivers of P-E changes. The mechanism behind the P-E changes is explored by decomposing the column integrated moisture flux convergence into thermodynamic, dynamic, and transient eddy components. High-resolution climate simulation improves the spatial pattern of P-E changes over the best available global reanalysis. High-resolution climate simulation also facilitates new and substantial findings regarding the role of thermodynamics and transient eddies in P-E changes reflected in observed changes in major river basins fed by runoff from the TP. The analysis revealed the contrasting convergence/divergence changes between the northwestern and southeastern TP and feedback through latent heat release as an important mechanism leading to the mean P-E changes in the TP.

  10. Reproducible high-resolution multispectral image acquisition in dermatology

    Science.gov (United States)

    Duliu, Alexandru; Gardiazabal, José; Lasser, Tobias; Navab, Nassir

    2015-07-01

    Multispectral image acquisitions are increasingly popular in dermatology, due to their improved spectral resolution which enables better tissue discrimination. Most applications however focus on restricted regions of interest, imaging only small lesions. In this work we present and discuss an imaging framework for high-resolution multispectral imaging on large regions of interest.

  11. Dye laser light for high-resolution classical photography

    International Nuclear Information System (INIS)

    Geissler, K.K.

    1982-01-01

    The test run with the bubble chamber HOLEBC in October 1981 offered the opportunity of checking the usefulness of de-speckled dye laser light for illumination purposes in high-resolution classical dark field photography of small bubble chambers. (orig./HSI)

  12. High-resolution seismic imaging of the Sohagpur Gondwana basin ...

    Indian Academy of Sciences (India)

    The quality of the high-resolution seismic data depends mainly on the data ..... metric rift geometry. Based on the .... Biswas S K 2003 Regional tectonic framework of the .... Sheth H C, Ray J S, Ray R, Vanderkluysen L, Mahoney J. J, Kumar A ...

  13. Pulmonary Gaucher's disease: high-resolution computed tomographic features

    International Nuclear Information System (INIS)

    Tunaci, A.; Berkmen, Y.M.; Goekmen, E.

    1995-01-01

    CT findings in pulmonary Gaucher's disease have not been previously reported. Chest radiograph of a patient with pulmonary involvement in type I Gaucher's disease proven by biopsy showed linear and reticulo-nodular opacities. High-resolution CT demonstrated thickening of the interlobular septa and between four and six small nodules within secondary lobules, probably each corresponding to an acinus. (orig.)

  14. High resolution techniques using scanning proton microprobe (SPM)

    International Nuclear Information System (INIS)

    Cholewa, M.; Saint, A.; Prawer, S.; Laird, J.S.; Legge, G.J.F.; Bardos, R.A.; Moorhead, G.F.; Taylor, G.N.; Stuart, S.A.; Howard, J.

    1994-01-01

    The very high resolution (down to 50 nm) achieved with low beam currents (fA) in a scanning ion microprobe have lead to many nondestructive techniques of microanalysis. This paper discusses recent developments and applications in the use of 3-D STIM (scanning transmission ion microscopy) Tomography, channeling STIM and IBIC (ion beam induced charge). (orig.)

  15. Structure Identification in High-Resolution Transmission Electron Microscopic Images

    DEFF Research Database (Denmark)

    Vestergaard, Jacob Schack; Kling, Jens; Dahl, Anders Bjorholm

    2014-01-01

    A connection between microscopic structure and macroscopic properties is expected for almost all material systems. High-resolution transmission electron microscopy is a technique offering insight into the atomic structure, but the analysis of large image series can be time consuming. The present ...

  16. Duchenne muscular dystrophy: High-resolution melting curve ...

    African Journals Online (AJOL)

    Duchenne muscular dystrophy: High-resolution melting curve analysis as an affordable diagnostic mutation scanning tool in a South African cohort. ... Genetic screening for D/BMD in South Africa currently includes multiple ligase-dependent probe amplification (MLPA) for exonic deletions and duplications and linkage ...

  17. Role of land state in a high resolution mesoscale model

    Indian Academy of Sciences (India)

    ... Proceedings – Mathematical Sciences · Resonance – Journal of Science ... Land surface characteristics; high resolution mesoscale model; Uttarakhand ... to predict realistic location, timing, amount,intensity and distribution of rainfall ... region embedded within two low pressure centers over Arabian Seaand Bay of Bengal.

  18. A high resolution powder diffractometer using focusing optics

    Indian Academy of Sciences (India)

    E-mail: siruguri@csr.ernet.in. Abstract. In this paper, we describe the design, construction and performance of a new high resolution neutron powder diffractometer that has been installed at the Dhruva reactor, Trombay, India. The instrument employs novel design concepts like the use of bent, perfect crystal monochromator ...

  19. Application of high resolution SNP arrays in patients with congenital ...

    Indian Academy of Sciences (India)

    clinical experience in implementing whole-genome high-resolution SNP arrays to investigate 33 patients with syndromic and .... Online Mendelian Inheritance in Man database (OMIM, ..... of damaged mitochondria through either autophagy or mito- ..... malformations: associations with maternal and infant character- istics in a ...

  20. Workshop on high-resolution, large-acceptance spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Zeidman, B. (ed.)

    1981-01-01

    The purpose of the Workshop on High-Resolution, Large-Acceptance Spectrometers was to provide a means for exchange of information among those actively engaged in the design and construction of these new spectrometers. Thirty-seven papers were prepared for the data base.

  1. Yeast expression proteomics by high-resolution mass spectrometry

    DEFF Research Database (Denmark)

    Walther, Tobias C; Olsen, Jesper Velgaard; Mann, Matthias

    2010-01-01

    -translational controls contribute majorly to regulation of protein abundance, for example in heat shock stress response. The development of new sample preparation methods, high-resolution mass spectrometry and novel bioinfomatic tools close this gap and allow the global quantitation of the yeast proteome under different...

  2. High resolution satellite imagery : from spies to pipeline management

    Energy Technology Data Exchange (ETDEWEB)

    Adam, S. [Canadian Geomatic Solutions Ltd., Calgary, AB (Canada); Farrell, M. [TransCanada Transmission, Calgary, AB (Canada)

    2000-07-01

    The launch of Space Imaging's IKONOS satellite in September 1999 has opened the door for corridor applications. The technology has been successfully implemented by TransCanada PipeLines in mapping over 1500 km of their mainline. IKONOS is the world's first commercial high resolution satellite which collects data at 1-meter black/white and 4-meter multi-spectral. Its use is regulated by the U.S. government. It is the best source of high resolution satellite image data. Other sources include the Indian Space Agency's IRS-1 C/D satellite and the Russian SPIN-2 which provides less reliable coverage. In addition, two more high resolution satellites may be launched this year to provide imagery every day of the year. IKONOS scenes as narrow as 5 km can be purchased. TransCanada conducted a pilot study to determine if high resolution satellite imagery is as effective as ortho-photos for identifying population structures within a buffer of TransCanada's east line right-of-way. The study examined three unique segments where residential, commercial, industrial and public features were compared. It was determined that IKONOS imagery is as good as digital ortho-photos for updating structures from low to very high density areas. The satellite imagery was also logistically easier than ortho-photos to acquire. This will be even more evident when the IKONOS image archives begins to grow. 4 tabs., 3 figs.

  3. Novel techniques in VUV high-resolution spectroscopy

    NARCIS (Netherlands)

    Ubachs, W.M.G.; Salumbides, E.J.; Eikema, K.S.E.; de Oliveira, N.; Nahon, L.

    2014-01-01

    Novel VUV sources and techniques for VUV spectroscopy are reviewed. Laser-based VUV sources have been developed via non-linear upconversion of laser pulses in the nanosecond (ns), the picosecond (ps), and femtosecond (fs) domain, and are applied in high-resolution gas phase spectroscopic studies.

  4. High resolution X-ray diffraction studies on unirradiated

    Indian Academy of Sciences (India)

    High-resolution X-ray diffraction technique, employing a three-crystal monochromator–collimator combination is used to study the irradiation induced defects in flux grown Sr-hexaferrite crystals irradiated with 50 MeV Li3+ ion beams at room temperature with a fluence value of 1 × 1014 ions/cm2. The diffraction curves of the ...

  5. High resolution STEM of quantum dots and quantum wires

    DEFF Research Database (Denmark)

    Kadkhodazadeh, Shima

    2013-01-01

    This article reviews the application of high resolution scanning transmission electron microscopy (STEM) to semiconductor quantum dots (QDs) and quantum wires (QWRs). Different imaging and analytical techniques in STEM are introduced and key examples of their application to QDs and QWRs...

  6. Pattern of interstitial lung disease detected by high resolution ...

    African Journals Online (AJOL)

    Background: Diffuse lung diseases constitute a major cause of morbidity and mortality worldwide. High Resolution Computed Tomography (HRCT) is the recommended imaging technique in the diagnosis, assessment and followup of these diseases. Objectives: To describe the pattern of HRCT findings in patients with ...

  7. Remote parallel rendering for high-resolution tiled display walls

    KAUST Repository

    Nachbaur, Daniel

    2014-11-01

    © 2014 IEEE. We present a complete, robust and simple to use hardware and software stack delivering remote parallel rendering of complex geometrical and volumetric models to high resolution tiled display walls in a production environment. We describe the setup and configuration, present preliminary benchmarks showing interactive framerates, and describe our contributions for a seamless integration of all the software components.

  8. Remote parallel rendering for high-resolution tiled display walls

    KAUST Repository

    Nachbaur, Daniel; Dumusc, Raphael; Bilgili, Ahmet; Hernando, Juan; Eilemann, Stefan

    2014-01-01

    © 2014 IEEE. We present a complete, robust and simple to use hardware and software stack delivering remote parallel rendering of complex geometrical and volumetric models to high resolution tiled display walls in a production environment. We describe the setup and configuration, present preliminary benchmarks showing interactive framerates, and describe our contributions for a seamless integration of all the software components.

  9. Human enamel structure studied by high resolution electron microscopy

    International Nuclear Information System (INIS)

    Wen, S.L.

    1989-01-01

    Human enamel structural features are characterized by high resolution electron microscopy. The human enamel consists of polycrystals with a structure similar to Ca10(PO4)6(OH)2. This article describes the structural features of human enamel crystal at atomic and nanometer level. Besides the structural description, a great number of high resolution images are included. Research into the carious process in human enamel is very important for human beings. This article firstly describes the initiation of caries in enamel crystal at atomic and unit-cell level and secondly describes the further steps of caries with structural and chemical demineralization. The demineralization in fact, is the origin of caries in human enamel. The remineralization of carious areas in human enamel has drawn more and more attention as its potential application is realized. This process has been revealed by high resolution electron microscopy in detail in this article. On the other hand, the radiation effects on the structure of human enamel are also characterized by high resolution electron microscopy. In order to reveal this phenomenon clearly, a great number of electron micrographs have been shown, and a physical mechanism is proposed. 26 references

  10. High resolution and high speed positron emission tomography data acquisition

    International Nuclear Information System (INIS)

    Burgiss, S.G.; Byars, L.G.; Jones, W.F.; Casey, M.E.

    1986-01-01

    High resolution positron emission tomography (PET) requires many detectors. Thus, data collection systems for PET must have high data rates, wide data paths, and large memories to histogram the events. This design uses the VMEbus to cost effectively provide these features. It provides for several modes of operation including real time sorting, list mode data storage, and replay of stored list mode data

  11. High resolution wind turbine wake measurements with a scanning lidar

    DEFF Research Database (Denmark)

    Herges, T. G.; Maniaci, D. C.; Naughton, B. T.

    2017-01-01

    High-resolution lidar wake measurements are part of an ongoing field campaign being conducted at the Scaled Wind Farm Technology facility by Sandia National Laboratories and the National Renewable Energy Laboratory using a customized scanning lidar from the Technical University of Denmark. One...

  12. High resolution mid-infrared spectroscopy based on frequency upconversion

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin; Hu, Qi; Tidemand-Lichtenberg, Peter

    2013-01-01

    signals can be analyzed. The obtainable frequency resolution is usually in the nm range where sub nm resolution is preferred in many applications, like gas spectroscopy. In this work we demonstrate how to obtain sub nm resolution when using upconversion. In the presented realization one object point...... high resolution spectral performance by observing emission from hot water vapor in a butane gas burner....

  13. Systematic high-resolution assessment of global hydropower potential

    NARCIS (Netherlands)

    Hoes, Olivier A C; Meijer, Lourens J J; Van Der Ent, Ruud J.|info:eu-repo/dai/nl/364164794; Van De Giesen, Nick C.

    2017-01-01

    Population growth, increasing energy demand and the depletion of fossil fuel reserves necessitate a search for sustainable alternatives for electricity generation. Hydropower could replace a large part of the contribution of gas and oil to the present energy mix. However, previous high-resolution

  14. High-Resolution Geologic Mapping of Martian Terraced Fan Deposits

    Science.gov (United States)

    Wolak, J. M.; Patterson, A. B.; Smith, S. D.; Robbins, N. N.

    2018-06-01

    This abstract documents our initial progress (year 1) mapping terraced fan features on Mars. Our objective is to investigate the role of fluids during fan formation and produce the first high-resolution geologic map (1:18k) of a terraced fan.

  15. Giant quiescent solar filament observed with high-resolution spectroscopy

    Science.gov (United States)

    Kuckein, C.; Verma, M.; Denker, C.

    2016-05-01

    Aims: An extremely large filament was studied in various layers of the solar atmosphere. The inferred physical parameters and the morphological aspects are compared with smaller quiescent filaments. Methods: A giant quiet-Sun filament was observed with the high-resolution Echelle spectrograph at the Vacuum Tower Telescope at Observatorio del Teide, Tenerife, Spain, on 2011 November 15. A mosaic of spectra (ten maps of 100″ × 182″) was recorded simultaneously in the chromospheric absorption lines Hα and Na I D2. Physical parameters of the filament plasma were derived using cloud model (CM) inversions and line core fits. The spectra were complemented with full-disk filtergrams (He I λ10830 Å, Hα, and Ca II K) of the Chromospheric Telescope (ChroTel) and full-disk magnetograms of the Helioseismic and Magnetic Imager (HMI). Results: The filament had extremely large linear dimensions (~817 arcsec), which corresponds to about 658 Mm along a great circle on the solar surface. A total amount of 175119 Hα contrast profiles were inverted using the CM approach. The inferred mean line-of-sight (LOS) velocity, Doppler width, and source function were similar to previous works of smaller quiescent filaments. However, the derived optical thickness was higher. LOS velocity trends inferred from the Hα line core fits were in accord but weaker than those obtained with CM inversions. Signatures of counter-streaming flows were detected in the filament. The largest brightening conglomerates in the line core of Na I D2 coincided well with small-scale magnetic fields as seen by HMI. Mixed magnetic polarities were detected close to the ends of barbs. The computation of photospheric horizontal flows based on HMI magnetograms revealed flow kernels with a size of 5-8 Mm and velocities of 0.30-0.45 km s-1 at the ends of the filament. Conclusions: The physical properties of extremely large filaments are similar to their smaller counterparts, except for the optical thickness, which in

  16. High-resolution boundary conditions of an old ice target near Dome C, Antarctica

    Science.gov (United States)

    Young, Duncan A.; Roberts, Jason L.; Ritz, Catherine; Frezzotti, Massimo; Quartini, Enrica; Cavitte, Marie G. P.; Tozer, Carly R.; Steinhage, Daniel; Urbini, Stefano; Corr, Hugh F. J.; van Ommen, Tas; Blankenship, Donald D.

    2017-08-01

    A high-resolution (1 km line spacing) aerogeophysical survey was conducted over a region near the East Antarctic Ice Sheet's Dome C that may hold a 1.5 Myr climate record. We combined new ice thickness data derived from an airborne coherent radar sounder with unpublished data that was in part unavailable for earlier compilations, and we were able to remove older data with high positional uncertainties. We generated a revised high-resolution digital elevation model (DEM) to investigate the potential for an old ice record in this region, and used laser altimetry to confirm a Cryosat-2 derived DEM for inferring the glaciological state of the candidate area. By measuring the specularity content of the bed, we were able to find an additional 50 subglacial lakes near the candidate site, and by Doppler focusing the radar data, we were able to map out the roughness of the bed at length scales of hundreds of meters. We find that the primary candidate region contains elevated rough topography interspersed with scattered subglacial lakes and some regions of smoother bed. Free subglacial water appears to be restricted from bed overlain by ice thicknesses of less than 3000 m. A site near the ice divide was selected for further investigation. The high resolution of this ice thickness data set also allows us to explore the nature of ice thickness uncertainties in the context of radar geometry and processing.

  17. Electrostatic ion trap and Fourier transform measurements for high-resolution mass spectrometry

    International Nuclear Information System (INIS)

    Bhushan, K. G.; Gadkari, S. C.; Yakhmi, J. V.; Sahni, V. C.

    2007-01-01

    We report on the development of an electrostatic ion trap for high-resolution mass spectrometry. The trap works on purely electrostatic fields and hence trapping and storing of ions is not mass restrictive, unlike other techniques based on Penning, Paul, or radio frequency quadrupole ion traps. It allows simultaneous trapping and studying of multiple mass species over a large mass range. Mass spectra were recorded in ''dispersive'' and ''self-bunching'' modes of ions. Storage lifetimes of about 100 ms and mass resolving power of about 20 000 could be achieved from the fifth harmonic Fourier transform spectrum of Xe ions recorded in the self-bunching mode

  18. Compressive Transient Imaging

    KAUST Repository

    Sun, Qilin

    2017-04-01

    High resolution transient/3D imaging technology is of high interest in both scientific research and commercial application. Nowadays, all of the transient imaging methods suffer from low resolution or time consuming mechanical scanning. We proposed a new method based on TCSPC and Compressive Sensing to achieve a high resolution transient imaging with a several seconds capturing process. Picosecond laser sends a serious of equal interval pulse while synchronized SPAD camera\\'s detecting gate window has a precise phase delay at each cycle. After capturing enough points, we are able to make up a whole signal. By inserting a DMD device into the system, we are able to modulate all the frames of data using binary random patterns to reconstruct a super resolution transient/3D image later. Because the low fill factor of SPAD sensor will make a compressive sensing scenario ill-conditioned, We designed and fabricated a diffractive microlens array. We proposed a new CS reconstruction algorithm which is able to denoise at the same time for the measurements suffering from Poisson noise. Instead of a single SPAD senor, we chose a SPAD array because it can drastically reduce the requirement for the number of measurements and its reconstruction time. Further more, it not easy to reconstruct a high resolution image with only one single sensor while for an array, it just needs to reconstruct small patches and a few measurements. In this thesis, we evaluated the reconstruction methods using both clean measurements and the version corrupted by Poisson noise. The results show how the integration over the layers influence the image quality and our algorithm works well while the measurements suffer from non-trival Poisson noise. It\\'s a breakthrough in the areas of both transient imaging and compressive sensing.

  19. OECD/DOE/CEA VVER-1000 Coolant Transient Benchmark. Summary Record of the Third Workshop (V1000-CT3)

    International Nuclear Information System (INIS)

    2005-01-01

    The overall objective of the VVER-1000 coolant transient (V1000CT) benchmark is to assess computer codes used in the safety analysis of VVER power plants, specifically for their use in analysis of reactivity transients in a VVER-1000. The V1000CT benchmark consists of two phases: V1000CT-1 is a simulation of the switching on of one main coolant pump (MCP) when the other three MCPs are in operation, and V1000CT-2 concerns calculation of coolant mixing tests and main steam line break (MSLB) scenarios. Each of the two phases contains three exercises. The reference problem chosen for simulation in Phase 1 is a MCP switching on when the other three main coolant pumps are in operation in a VVER-1000. This event is characterized by rapid increase in the flow through the core resulting in a coolant temperature decrease, which is spatially dependent. This leads to insertion of spatially distributed positive reactivity due to the modelled feedback mechanisms and non-symmetric power distribution. Simulation of the transient requires evaluation of core response from a multi-dimensional perspective (coupled three-dimensional neutronics/core thermal-hydraulics) supplemented by a one-dimensional simulation of the remainder of the reactor coolant system. Three exercises are defined in the framework of Phase 1: a) Exercise 1 - Point kinetics plant simulation; b) Exercise 2 - Coupled 3-D neutronics/core thermal-hydraulics response evaluation; c) Exercise 3 - Best-estimate coupled 3-D core/plant system transient modelling. In addition to the measured (experiment) scenario, extreme calculation scenarios were defined in the frame of Exercise 3 for better testing 3-D neutronics/thermal-hydraulics techniques. The proposals concerned: rod ejection simulations with scram set points at two different power levels. The technical topics presented at this workshop were: Review of the benchmark activities after the 2. Workshop; - Discussion of participant's feedback and introduced modifications

  20. High-resolution axial MR imaging of tibial stress injuries

    Directory of Open Access Journals (Sweden)

    Mammoto Takeo

    2012-05-01

    Full Text Available Abstract Purpose To evaluate the relative involvement of tibial stress injuries using high-resolution axial MR imaging and the correlation with MR and radiographic images. Methods A total of 33 patients with exercise-induced tibial pain were evaluated. All patients underwent radiograph and high-resolution axial MR imaging. Radiographs were taken at initial presentation and 4 weeks later. High-resolution MR axial images were obtained using a microscopy surface coil with 60 × 60 mm field of view on a 1.5T MR unit. All images were evaluated for abnormal signals of the periosteum, cortex and bone marrow. Results Nineteen patients showed no periosteal reaction at initial and follow-up radiographs. MR imaging showed abnormal signals in the periosteal tissue and partially abnormal signals in the bone marrow. In 7 patients, periosteal reaction was not seen at initial radiograph, but was detected at follow-up radiograph. MR imaging showed abnormal signals in the periosteal tissue and entire bone marrow. Abnormal signals in the cortex were found in 6 patients. The remaining 7 showed periosteal reactions at initial radiograph. MR imaging showed abnormal signals in the periosteal tissue in 6 patients. Abnormal signals were seen in the partial and entire bone marrow in 4 and 3 patients, respectively. Conclusions Bone marrow abnormalities in high-resolution axial MR imaging were related to periosteal reactions at follow-up radiograph. Bone marrow abnormalities might predict later periosteal reactions, suggesting shin splints or stress fractures. High-resolution axial MR imaging is useful in early discrimination of tibial stress injuries.

  1. High-resolution axial MR imaging of tibial stress injuries

    Science.gov (United States)

    2012-01-01

    Purpose To evaluate the relative involvement of tibial stress injuries using high-resolution axial MR imaging and the correlation with MR and radiographic images. Methods A total of 33 patients with exercise-induced tibial pain were evaluated. All patients underwent radiograph and high-resolution axial MR imaging. Radiographs were taken at initial presentation and 4 weeks later. High-resolution MR axial images were obtained using a microscopy surface coil with 60 × 60 mm field of view on a 1.5T MR unit. All images were evaluated for abnormal signals of the periosteum, cortex and bone marrow. Results Nineteen patients showed no periosteal reaction at initial and follow-up radiographs. MR imaging showed abnormal signals in the periosteal tissue and partially abnormal signals in the bone marrow. In 7 patients, periosteal reaction was not seen at initial radiograph, but was detected at follow-up radiograph. MR imaging showed abnormal signals in the periosteal tissue and entire bone marrow. Abnormal signals in the cortex were found in 6 patients. The remaining 7 showed periosteal reactions at initial radiograph. MR imaging showed abnormal signals in the periosteal tissue in 6 patients. Abnormal signals were seen in the partial and entire bone marrow in 4 and 3 patients, respectively. Conclusions Bone marrow abnormalities in high-resolution axial MR imaging were related to periosteal reactions at follow-up radiograph. Bone marrow abnormalities might predict later periosteal reactions, suggesting shin splints or stress fractures. High-resolution axial MR imaging is useful in early discrimination of tibial stress injuries. PMID:22574840

  2. FTIR free-jet set-up for the high resolution spectroscopic investigation of condensable species

    Science.gov (United States)

    Georges, R.; Bonnamy, A.; Benidar, A.; Decroi, M.; Boissoles, J.

    2002-05-01

    An existing experimental set-up combining Fourier transform infrared (FTIR) spectroscopy and free-jet cooling has been modified significantly to allow high resolution studies of the spectrum of monomer species which are liquid under standard conditions. Evaporation of the liquid samples is controlled by a condenser apparatus which is described. A supersonic planar expansion issuing from a narrow aperture is preferred for its very high cooling rate. Such an expansion, probed with a pitot tube, has a zone of limited temperature gradient close to the nozzle exit. The continuum isentropic model appears well suited to describing the thermodynamic properties of the flow up to a high number of nozzle diameters downstream. High resolution spectra of benzene and methanol have been recorded in the 3 µm wavelength range, and their analysis demonstrates a well defined rotational temperature in the 20-25 K range.

  3. High resolution optically stimulated luminescence dating of a sediment core from the southwestern Sea of Okhotsk

    DEFF Research Database (Denmark)

    Sugisaki, S.; Buylaert, J. P.; Murray, A. S.

    2012-01-01

    (D-e), with stimulation by both infrared and blue light. The suitability of the measurement procedure was confirmed using dose recovery tests. A high resolution record (similar to 2 OSL ages/m) identified clear sedimentation rate changes down the core. The OSL ages are significantly dependent......Optically stimulated luminescence (OSL) dating is now widely accepted as a chronometer for terrestrial sediment. More recently, it has been suggested that OSL may also be useful in the dating of deep-sea marine sediments. In this paper, we test the usefulness of high resolution quartz OSL dating...... in application to a 19 m marine sediment core (MR0604-PC04A) taken from the southwestern Sea of Okhotsk, immediately to the north of Hokkaido, Japan. Fine-grained quartz (4 to 11 mu m) was chosen as the dosimeter, and a single-aliquot regenerative-dose protocol was used for the determination of equivalent dose...

  4. OECD/DOE/CEA VVER-1000 Coolant Transient Benchmark. Summary Record of the First Workshop (V1000-CT1)

    International Nuclear Information System (INIS)

    2003-01-01

    The first workshop for the VVER-1000 Coolant Transient Benchmark TT Benchmark was hosted by the Commissariat a l'Energie Atomique, Centre d'Etudes de Saclay, France. The V1000CT benchmark defines standard problems for validation of coupled three-dimensional (3-D) neutron-kinetics/system thermal-hydraulics codes for application to Soviet-designed VVER-1000 reactors using actual plant data without any scaling. The overall objective is to access computer codes used in the safety analysis of VVER power plants, specifically for their use in reactivity transient simulations in a VVER-1000. The V1000CT benchmark consists of two phases: V1000CT-1 - simulation of the switching on of one main coolant pump (MCP) while the other three MCP are in operation, and V1000CT- 2 - calculation of coolant mixing tests and Main Steam Line Break (MSLB) scenario. Further background information on this benchmark can be found at the OECD/NEA benchmark web site . The purpose of the first workshop was to review the benchmark activities after the Starter Meeting held last year in Dresden, Germany: to discuss the participants' feedback and modifications introduced in the Benchmark Specifications on Phase 1; to present and to discuss modelling issues and preliminary results from the three exercises of Phase 1; to discuss the modelling issues of Exercise 1 of Phase 2; and to define work plan and schedule in order to complete the two phases

  5. High-resolution structure of the native histone octamer

    International Nuclear Information System (INIS)

    Wood, Christopher M.; Nicholson, James M.; Lambert, Stanley J.; Chantalat, Laurent; Reynolds, Colin D.; Baldwin, John P.

    2005-01-01

    The high-resolution (1.90 Å) model of the native histone octamer allows structural comparisons to be made with the nucleosome-core particle, along with an identification of a likely core-histone binding site. Crystals of native histone octamers (H2A–H2B)–(H4–H3)–(H3′–H4′)–(H2B′–H2A′) from chick erythrocytes in 2 M KCl, 1.35 M potassium phosphate pH 6.9 diffract X-rays to 1.90 Å resolution, yielding a structure with an R work value of 18.7% and an R free of 22.2%. The crystal space group is P6 5 , the asymmetric unit of which contains one complete octamer. This high-resolution model of the histone-core octamer allows further insight into intermolecular interactions, including water molecules, that dock the histone dimers to the tetramer in the nucleosome-core particle and have relevance to nucleosome remodelling. The three key areas analysed are the H2A′–H3–H4 molecular cluster (also H2A–H3′–H4′), the H4–H2B′ interaction (also H4′–H2B) and the H2A′–H4 β-sheet interaction (also H2A–H4′). The latter of these three regions is important to nucleosome remodelling by RNA polymerase II, as it is shown to be a likely core-histone binding site, and its disruption creates an instability in the nucleosome-core particle. A majority of the water molecules in the high-resolution octamer have positions that correlate to similar positions in the high-resolution nucleosome-core particle structure, suggesting that the high-resolution octamer model can be used for comparative studies with the high-resolution nucleosome-core particle

  6. High resolution color imagery for orthomaps and remote sensing

    Energy Technology Data Exchange (ETDEWEB)

    Fricker, Peter [Leica Geosystems GIS and Mapping, LLC (Switzerland); Gallo, M. Guillermo [Leica Geosystems GIS and Mapping, LLC (United States)

    2005-07-01

    The ADS40 Airborne Digital Pushbroom Sensor is currently the only commercial sensor capable of acquiring color and false color strip images in the low decimeter range at the same high resolution as the black and white stereo images. This high resolution of 12,000 pixels across the entire swath and 100% forward overlap in the image strips result in high quality DSM's, True Ortho's and at the same time allow unbiased remote sensing applications due to color strip images unchanged by pan-sharpening. The paper gives details on how the pushbroom sensor achieves these seemingly difficult technical challenges. It describes how a variety of mapping applications benefit from this sensor, a sensor which acts as a satellite pushbroom sensor within the airborne environment. (author)

  7. Ring artifact correction for high-resolution micro CT

    International Nuclear Information System (INIS)

    Kyriakou, Yiannis; Prell, Daniel; Kalender, Willi A

    2009-01-01

    In high-resolution micro CT using flat detectors (FD), imperfect or defect detector elements may cause concentric-ring artifacts due to their continuous over- or underestimation of attenuation values, which often disturb image quality. We here present a dedicated image-based ring artifact correction method for high-resolution micro CT, based on median filtering of the reconstructed image and working on a transformed version of the reconstructed images in polar coordinates. This post-processing method reduced ring artifacts in the reconstructed images and improved image quality for phantom and in in vivo scans. Noise and artifacts were reduced both in transversal and in multi-planar reformations along the longitudinal axis. (note)

  8. High resolution spectroscopy in solids by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Bonagamba, T.J.

    1991-07-01

    The nuclear magnetic resonance (NMR) techniques for High Resolution Spectroscopy in Solids are described. Also the construction project of a partially home made spectrometer and its applications in the characterization of solid samples are shown in detail. The high resolution spectrometer used is implemented with the double resonance multiple pulses sequences and magic angle spinning (MAS) and can be used with solid and liquid samples. The maximum spinning frequency for the MAS experiment is in excess of 5 Khz, the double resonance sequences can be performed with any type of nucleus, in the variable temperature operating range with nitrogen gas: -120 0 C to +160 0 C, and is fully controlled by a Macintosh IIci microcomputer. (author)

  9. High resolution radar satellite imagery analysis for safeguards applications

    Energy Technology Data Exchange (ETDEWEB)

    Minet, Christian; Eineder, Michael [German Aerospace Center, Remote Sensing Technology Institute, Department of SAR Signal Processing, Wessling, (Germany); Rezniczek, Arnold [UBA GmbH, Herzogenrath, (Germany); Niemeyer, Irmgard [Forschungszentrum Juelich, Institue of Energy and Climate Research, IEK-6: Nuclear Waste Management and Reactor Safety, Juelich, (Germany)

    2011-12-15

    For monitoring nuclear sites, the use of Synthetic Aperture Radar (SAR) imagery shows essential promises. Unlike optical remote sensing instruments, radar sensors operate under almost all weather conditions and independently of the sunlight, i.e. time of the day. Such technical specifications are required both for continuous and for ad-hoc, timed surveillance tasks. With Cosmo-Skymed, TerraSARX and Radarsat-2, high-resolution SAR imagery with a spatial resolution up to 1m has recently become available. Our work therefore aims to investigate the potential of high-resolution TerraSAR data for nuclear monitoring. This paper focuses on exploiting amplitude of a single acquisition, assessing amplitude changes and phase differences between two acquisitions, and PS-InSAR processing of an image stack.

  10. High resolution reservoir geological modelling using outcrop information

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Changmin; Lin Kexiang; Liu Huaibo [Jianghan Petroleum Institute, Hubei (China)] [and others

    1997-08-01

    This is China`s first case study of high resolution reservoir geological modelling using outcrop information. The key of the modelling process is to build a prototype model and using the model as a geological knowledge bank. Outcrop information used in geological modelling including seven aspects: (1) Determining the reservoir framework pattern by sedimentary depositional system and facies analysis; (2) Horizontal correlation based on the lower and higher stand duration of the paleo-lake level; (3) Determining the model`s direction based on the paleocurrent statistics; (4) Estimating the sandbody communication by photomosaic and profiles; (6) Estimating reservoir properties distribution within sandbody by lithofacies analysis; and (7) Building the reservoir model in sandbody scale by architectural element analysis and 3-D sampling. A high resolution reservoir geological model of Youshashan oil field has been built by using this method.

  11. High resolution spectroscopy in the microwave and far infrared

    Science.gov (United States)

    Pickett, Herbert M.

    1990-01-01

    High resolution rotational spectroscopy has long been central to remote sensing techniques in atmospheric sciences and astronomy. As such, laboratory measurements must supply the required data to make direct interpretation of data for instruments which sense atmospheres using rotational spectra. Spectral measurements in the microwave and far infrared regions are also very powerful tools when combined with infrared measurements for characterizing the rotational structure of vibrational spectra. In the past decade new techniques were developed which have pushed high resolution spectroscopy into the wavelength region between 25 micrometers and 2 mm. Techniques to be described include: (1) harmonic generation of microwave sources, (2) infrared laser difference frequency generation, (3) laser sideband generation, and (4) ultrahigh resolution interferometers.

  12. Automated data processing of high-resolution mass spectra

    DEFF Research Database (Denmark)

    Hansen, Michael Adsetts Edberg; Smedsgaard, Jørn

    of the massive amounts of data. We present an automated data processing method to quantitatively compare large numbers of spectra from the analysis of complex mixtures, exploiting the full quality of high-resolution mass spectra. By projecting all detected ions - within defined intervals on both the time...... infusion of crude extracts into the source taking advantage of the high sensitivity, high mass resolution and accuracy and the limited fragmentation. Unfortunately, there has not been a comparable development in the data processing techniques to fully exploit gain in high resolution and accuracy...... infusion analyses of crude extract to find the relationship between species from several species terverticillate Penicillium, and also that the ions responsible for the segregation can be identified. Furthermore the process can automate the process of detecting unique species and unique metabolites....

  13. Towards high-resolution positron emission tomography for small volumes

    International Nuclear Information System (INIS)

    McKee, B.T.A.

    1982-01-01

    Some arguments are made regarding the medical usefulness of high spatial resolution in positron imaging, even if limited to small imaged volumes. Then the intrinsic limitations to spatial resolution in positron imaging are discussed. The project to build a small-volume, high resolution animal research prototype (SHARP) positron imaging system is described. The components of the system, particularly the detectors, are presented and brief mention is made of data acquisition and image reconstruction methods. Finally, some preliminary imaging results are presented; a pair of isolated point sources and 18 F in the bones of a rabbit. Although the detector system is not fully completed, these first results indicate that the goals of high sensitivity and high resolution (4 mm) have been realized. (Auth.)

  14. High-resolution investigations of edge effects in neutron imaging

    International Nuclear Information System (INIS)

    Strobl, M.; Kardjilov, N.; Hilger, A.; Kuehne, G.; Frei, G.; Manke, I.

    2009-01-01

    Edge enhancement is the main effect measured by the so-called inline or propagation-based neutron phase contrast imaging method. The effect has originally been explained by diffraction, and high spatial coherence has been claimed to be a necessary precondition. However, edge enhancement has also been found in conventional imaging with high resolution. In such cases the effects can produce artefacts and hinder quantification. In this letter the edge effects at cylindrical shaped samples and long straight edges have been studied in detail. The enhancement can be explained by refraction and total reflection. Using high-resolution imaging, where spatial resolutions better than 50 μm could be achieved, refraction and total reflection peaks - similar to diffraction patterns - could be separated and distinguished.

  15. SRS station 16.3: high-resolution applications

    CERN Document Server

    Murphy, B M; Golshan, M; Moore, M; Reid, J; Kowalski, G

    2001-01-01

    Station 16.3 is a high-resolution X-ray diffraction beamline at Daresbury Laboratory Synchrotron Radiation Source. The data presented demonstrate the high-resolution available on the station utilising the recently commissioned four-reflection Si 1 1 1 monochromator and three-reflection Si 1 1 1 analyser. For comparison, a reciprocal space map of the two-bounce Si 1 1 1 monochromator and two-bounce analyser is also shown. Operation of the station is illustrated with examples for silicon, and for diamond. Lattice parameter variations were measured with accuracies in the part per million range and lattice tilts at the arc second level (DuMond, Phys. Rev. 52 (1937) 872).

  16. High-resolution nuclear magnetic resonance studies of proteins.

    Science.gov (United States)

    Jonas, Jiri

    2002-03-25

    The combination of advanced high-resolution nuclear magnetic resonance (NMR) techniques with high-pressure capability represents a powerful experimental tool in studies of protein folding. This review is organized as follows: after a general introduction of high-pressure, high-resolution NMR spectroscopy of proteins, the experimental part deals with instrumentation. The main section of the review is devoted to NMR studies of reversible pressure unfolding of proteins with special emphasis on pressure-assisted cold denaturation and the detection of folding intermediates. Recent studies investigating local perturbations in proteins and the experiments following the effects of point mutations on pressure stability of proteins are also discussed. Ribonuclease A, lysozyme, ubiquitin, apomyoglobin, alpha-lactalbumin and troponin C were the model proteins investigated.

  17. Turbine component casting core with high resolution region

    Science.gov (United States)

    Kamel, Ahmed; Merrill, Gary B.

    2014-08-26

    A hollow turbine engine component with complex internal features can include a first region and a second, high resolution region. The first region can be defined by a first ceramic core piece formed by any conventional process, such as by injection molding or transfer molding. The second region can be defined by a second ceramic core piece formed separately by a method effective to produce high resolution features, such as tomo lithographic molding. The first core piece and the second core piece can be joined by interlocking engagement that once subjected to an intermediate thermal heat treatment process thermally deform to form a three dimensional interlocking joint between the first and second core pieces by allowing thermal creep to irreversibly interlock the first and second core pieces together such that the joint becomes physically locked together providing joint stability through thermal processing.

  18. Precision crystal alignment for high-resolution electron microscope imaging

    International Nuclear Information System (INIS)

    Wood, G.J.; Beeching, M.J.

    1990-01-01

    One of the more difficult tasks involved in obtaining quality high-resolution electron micrographs is the precise alignment of a specimen into the required zone. The current accepted procedure, which involves changing to diffraction mode and searching for symmetric point diffraction pattern, is insensitive to small amounts of misalignment and at best qualitative. On-line analysis of the fourier space representation of the image, both for determining and correcting crystal tilt, is investigated. 8 refs., 42 figs

  19. A high resolution large dynamic range TDC circuit implementation

    International Nuclear Information System (INIS)

    Lei Wuhu; Liu Songqiu; Ye Weiguo; Han Hui; Li Pengyu

    2003-01-01

    Time measurement technology is usually used in nuclear experimentation. There are many methods of time measurement. The implementation method of Time to Digital Conversion (TDC) by means of electronic is a classical technology. The range and resolution of TDC is different according with different usage. A wide range and high resolution TDC circuit, including its theory and implementation way, is introduced in this paper. The test result is also given. (authors)

  20. A high resolution large dynamic range TDC circuit implementation

    International Nuclear Information System (INIS)

    Lei Wuhu; Liu Songqiu; Li Pengyu; Han Hui; Ye Yanlin

    2005-01-01

    Time measurement technology is usually used in nuclear experimentation. There are many methods of time measurement. The implementation method of Time to Digital Conversion (TDC) by means of electronics is a classical technology. The range and resolution of TDC is different according with different usage. A wide range and high resolution TDC circuit, including its theory and implementation way, is introduced in this paper. The test result is also given. (authors)

  1. Constraining Stochastic Parametrisation Schemes Using High-Resolution Model Simulations

    Science.gov (United States)

    Christensen, H. M.; Dawson, A.; Palmer, T.

    2017-12-01

    Stochastic parametrisations are used in weather and climate models as a physically motivated way to represent model error due to unresolved processes. Designing new stochastic schemes has been the target of much innovative research over the last decade. While a focus has been on developing physically motivated approaches, many successful stochastic parametrisation schemes are very simple, such as the European Centre for Medium-Range Weather Forecasts (ECMWF) multiplicative scheme `Stochastically Perturbed Parametrisation Tendencies' (SPPT). The SPPT scheme improves the skill of probabilistic weather and seasonal forecasts, and so is widely used. However, little work has focused on assessing the physical basis of the SPPT scheme. We address this matter by using high-resolution model simulations to explicitly measure the `error' in the parametrised tendency that SPPT seeks to represent. The high resolution simulations are first coarse-grained to the desired forecast model resolution before they are used to produce initial conditions and forcing data needed to drive the ECMWF Single Column Model (SCM). By comparing SCM forecast tendencies with the evolution of the high resolution model, we can measure the `error' in the forecast tendencies. In this way, we provide justification for the multiplicative nature of SPPT, and for the temporal and spatial scales of the stochastic perturbations. However, we also identify issues with the SPPT scheme. It is therefore hoped these measurements will improve both holistic and process based approaches to stochastic parametrisation. Figure caption: Instantaneous snapshot of the optimal SPPT stochastic perturbation, derived by comparing high-resolution simulations with a low resolution forecast model.

  2. High-Resolution Imaging of Colliding and Merging Galaxies

    Science.gov (United States)

    Whitmore, Brad

    1991-07-01

    We propose to obtain high-resolution images, using the WF/PC, of two colliding and merging galaxies (i.e., NGC 4038/4039 = "The Antennae" and NGC 7252 ="Atoms-for-Peace Galaxy". Our goal is to use HST to make critical observations of each object in order to gain a better understanding of the various phases of the merger process. Our primary objective is to determine whether globular clusters are formed during mergers\\?

  3. PROFIL-360 high resolution steam generator tube profilometry system

    International Nuclear Information System (INIS)

    Glass, S.W.

    1985-01-01

    A high-resolution profilometry system, PROFIL 360, has been developed to assess the condition of steam generator tubes and rapidly produce the data to evaluate the potential for developing in-service leaks. The probe has an electromechanical sensor in a rotating head. This technique has been demonstrated in the field, saving tubes that would have been plugged with the go-gauge criterion and indicating plugging other high-risk candidates that might otherwise not have been removed from service

  4. Profil-360 high resolution steam generator tube profilometry system

    International Nuclear Information System (INIS)

    Glass, S.W.

    1985-01-01

    A high-resolution profilometry system, PROFIL 360, has been developed to assess the condition of steam generator tubes and rapidly produce the data to evaluate the potential for developing in-service leaks. The probe has an electromechanical sensor in a rotating head. This technique has been demonstrated in the field, saving tubes that would have been plugged with the go-gauge criterion and indicating plugging other high-risk candidates that might otherwise not have been removed from service

  5. Tuberculous otitis media: findings on high-resolution CT

    International Nuclear Information System (INIS)

    Lungenschmid, D.; Buchberger, W.; Schoen, G.; Schoepf, R.; Mihatsch, T.; Birbamer, G.; Wicke, K.

    1993-01-01

    We describe two cases of tuberculous otitis media studied with high-resolution computed tomography (CT). Findings included extensive soft tissue densities with fluid levels in the tympanic cavity, the antrum, the mastoid and petrous air cells. Multifocal bony erosions and reactive bone sclerosis were seen as well. CT proved valuable for planning therapy by accurately displaying the involvement of the various structures of the middle and inner ear. However, the specific nature of the disease could only be presumed. (orig.)

  6. Environmental high resolution electron microscopy and applications to chemical science

    OpenAIRE

    Boyes, Edward; Gai, Pratibha

    2017-01-01

    An environmental cell high resolution electron microscope (EHREM) has been developed for in situ studies of dynamic chemical reactions on the atomic scale. It allows access to metastable intermediate phases of catalysts and to sequences of reversible microstructural and chemical development associated with the activation, deactivation and poisoning of a catalyst. Materials transported through air can be restored or recreated and samples damaged, e.g. by dehydration, by the usual vacuum enviro...

  7. Creating the High-Resolution Settlement Layer - lessons learned

    Science.gov (United States)

    Gros, A.

    2017-12-01

    Facebook publishes the High-resolution Settlement Layer (HRSL: https://ciesin.columbia.edu/data/hrsl/) in collaboration with Columbia University's CIESIN institute and the World Bank. So far, data for 13 countries have been published over the past nine months. HRSL data for Burkina Faso, Ghana, Haiti, Ivory Coast, Madagascar, Malawi, Mexico, The Philippines, Rwanda, South Africa, Sri Lanka, Thailand, and Uganda are available for download. We will present a status update and report on lessons learned.

  8. High-resolution spectroscopy of gases for industrial applications

    OpenAIRE

    Fateev, Alexander; Clausen, Sønnik

    2012-01-01

    High-resolution spectroscopy of gases is a powerful technique which has various fundamental and practical applications: in situ simultaneous measurements of gas temperature and gas composition, radiative transfer modeling, validation of existing and developing of new databases and etc. Existing databases (e.g. HITRAN, HITEMP or CDSD) can normally be used for absorption spectra calculations at limited temperature/pressure ranges. Therefore experimental measurements of absorption/transmission s...

  9. High-resolution CT of lesions of the optic nerve

    International Nuclear Information System (INIS)

    Peyster, R.G.; Hoover, E.D.; Hershey, B.L.; Haskin, M.E.

    1983-01-01

    The optic nerves are well demonstrated by high-resolution computed tomography. Involvement of the optic nerve by optic gliomas and optic nerve sheath meningiomas is well known. However, nonneoplastic processes such as increased intracranial pressure, optic neuritis, Grave ophthalmopathy, and orbital pseudotumor may also alter the appearance of the optic nerve/sheath on computed tomography. Certain clinical and computed tomographic features permit distinction of these nonneoplastic tumefactions from tumors

  10. Detectors for high resolution dynamic positron emission tomography

    International Nuclear Information System (INIS)

    Derenzo, S.E.; Budinger, T.F.; Huesman, R.H.

    1985-01-01

    Tomography is the technique of producing a photographic image of an opaque specimen by transmitting a beam of x-rays or gamma rays through the specimen onto an adjacent photographic film. The image results from variations in thickness, density, and chemical composition, of the specimen. This technique is used to study the metabolism of the human brain. This article examines the design of equipment used for high resolution dynamic positron emission tomography. 27 references, 5 figures, 3 tables

  11. High-Resolution Esophageal Manometry: A Time Motion Study

    Directory of Open Access Journals (Sweden)

    Daniel C Sadowski

    2008-01-01

    Full Text Available INTRODUCTION: High-resolution manometry (HRM of the esophagus is a new technique that provides a more precise assessment of esophageal motility than conventional techniques. Because HRM measures pressure events along the entire length of the esophagus simultaneously, clinical procedure time should be shorter because less catheter manipulation is required. According to manufacturer advertising, the new HRM system is more accurate and up to 50% faster than conventional methods.

  12. High Resolution Mass Spectrometry of Polyfluorinated Polyether-Based Formulation

    DEFF Research Database (Denmark)

    Dimzon, Ian Ken; Trier, Xenia; Frömel, Tobias

    2016-01-01

    High resolution mass spectrometry (HRMS) was successfully applied to elucidate the structure of a polyfluorinated polyether (PFPE)-based formulation. The mass spectrum generated from direct injection into the MS was examined by identifying the different repeating units manually and with the aid o......-fluorinated polymers. The information from MS is essential in studying the physico-chemical properties of PFPEs and can help in assessing the risks they pose to the environment and to human health. Graphical Abstract ᅟ....

  13. Chronic pneumonitis of infancy: high-resolution CT findings

    International Nuclear Information System (INIS)

    Olsen, Oeystein E.; Owens, Catherine M.; Sebire, Neil J.; Jaffe, Adam

    2004-01-01

    Chronic pneumonitis of infancy (CPI) is a very rare entity. We report the chest radiography and high-resolution CT (HRCT) findings in an infant with histopathologically confirmed CPI. The child was admitted for intensive care 18 h after birth and died at 39 days of age. On HRCT there was diffuse ground-glass change, interlobular septal thickening and discrete centrilobular nodules. An accurate diagnosis is crucial for correct management; however, several entities with the same HRCT findings are recognized. (orig.)

  14. Acute pulmonary injury: high-resolution CT and histopathological spectrum

    Science.gov (United States)

    Obadina, E T; Torrealba, J M

    2013-01-01

    Acute lung injury usually causes hypoxaemic respiratory failure and acute respiratory distress syndrome (ARDS). Although diffuse alveolar damage is the hallmark of ARDS, other histopathological patterns of injury, such as acute and fibrinoid organising pneumonia, can be associated with acute respiratory failure. Acute eosinophilic pneumonia can also cause acute hypoxaemic respiratory failure and mimic ARDS. This pictorial essay reviews the high-resolution CT findings of acute lung injury and the correlative histopathological findings. PMID:23659926

  15. Aspects of pulmonary histiocytosis X on high resolution computed tomography

    International Nuclear Information System (INIS)

    Costa, N.S.S.; Castro Lessa Angela, M.T. de; Angelo Junior, J.R.L.; Silva, F.M.D.; Kavakama, J.; Carvalho, C.R.R. de; Cerri, G.G.

    1995-01-01

    Pulmonary histiocytosis X is a disease that occurs in young adults and presents with nodules and cysts, mainly in upper lobes, with consequent pulmonary fibrosis. These pulmonary changes are virtually pathognomonic findings on high resolution computed tomography, that allows estimate the area of the lung involved and distinguish histiocytosis X from other disorders that also produces nodules and cysts. (author). 10 refs, 2 tabs, 6 figs

  16. Concept for a new high resolution high intensity diffractometer

    Energy Technology Data Exchange (ETDEWEB)

    Stuhr, U [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    A concept of a new time-of-flight powder-diffractometer for a thermal neutral beam tube at SINQ is presented. The design of the instrument optimises the contradictory conditions of high intensity and high resolution. The high intensity is achieved by using many neutron pulses simultaneously. By analysing the time-angle-pattern of the detected neutrons an assignment of the neutrons to a single pulse is possible. (author) 3 figs., tab., refs.

  17. COST EFFECTIVE AND HIGH RESOLUTION SUBSURFACE CHARACTERIZATION USING HYDRAULIC TOMOGRAPHY

    Science.gov (United States)

    2017-08-01

    objective of this project is to provide the DoD and its remediation contractors with the HT technology for delineating the spatial distribution of...STATEMENT Approved for public release; distribution is unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Hydraulic Tomography ( HT ) is a high-resolution...performance of subsurface remedial actions at environmental sites. The good technical performance and cost-effectiveness of HT have been demonstrated in

  18. High resolution solar soft X-ray spectrometer

    International Nuclear Information System (INIS)

    Zhang Fei; Wang Huanyu; Peng Wenxi; Liang Xiaohua; Zhang Chunlei; Cao Xuelei; Jiang Weichun; Zhang Jiayu; Cui Xingzhu

    2012-01-01

    A high resolution solar soft X-ray spectrometer (SOX) payload onboard a satellite is developed. A silicon drift detector (SDD) is adopted as the detector of the SOX spectrometer. The spectrometer consists of the detectors and their readout electronics, a data acquisition unit and a payload data handling unit. A ground test system is also developed to test SOX. The test results show that the design goals of the spectrometer system have been achieved. (authors)

  19. High-Resolution Wind Measurements for Offshore Wind Energy Development

    Science.gov (United States)

    Nghiem, Son V.; Neumann, Gregory

    2011-01-01

    A mathematical transform, called the Rosette Transform, together with a new method, called the Dense Sampling Method, have been developed. The Rosette Transform is invented to apply to both the mean part and the fluctuating part of a targeted radar signature using the Dense Sampling Method to construct the data in a high-resolution grid at 1-km posting for wind measurements over water surfaces such as oceans or lakes.

  20. High resolution electromagnetic methods and low frequency dispersion of rock conductivity

    Directory of Open Access Journals (Sweden)

    V. V. Ageev

    1999-06-01

    Full Text Available The influence of frequency dispersion of conductivity (induced polarization of rocks on the results of electromagnetic (EM sounding was studied on the basis of calculation of electric field of vertical magnetic dipole above horizontally layered polarizable sections. Frequency dispersion was approximated by the Debye formula. Polarizable homogeneous halfspace, two, three and multilayered sections were analyzed in frequency and time domains. The calculations for different values of chargeability and time constants of polarization were performed. In the far zone of a source, the IP of rocks led to quasi-wave phenomena. They produced rapid fluctuations of frequency and transient sounding curves (interference phenomena, multireflections in polarizable layers. In the case of transient sounding in the near zone of a source quasistatic distortions prevailed, caused by the counter electromotive force arising in polarizable layers which may lead to strong changes in transient curves. In some cases quasiwave and quasistatic phenomena made EM sounding curves non-interpretable in the class of quasistationary curves over non-dispersive sections. On the other hand, they could increase the resolution and depth of investigation of EM sounding. This was confirmed by an experience of "high-resolution" electroprospecting in Russia. The problem of interpretation of EM sounding data in polarizable sections is nonunique. To achieve uniqueness it is probably necessary to complement them by soundings of other type.

  1. High resolution electromagnetic methods and low frequency dispersion of rock conductivity

    International Nuclear Information System (INIS)

    Svetov, B.S.; Ageev, V.V.

    1999-01-01

    The influence of frequency dispersion of conductivity (induced polarization) of rocks on the results of electromagnetic (EM) sounding was studied on the basis of calculation of electric field of vertical magnetic dipole above horizontally layered polarizable sections. Frequency dispersion was approximated by the Debye formula. Polarizable homogeneous half space, two, three and multilayered section were analyzed in frequency and tim domains. The calculations for different values of charge ability and time constants of polarization were performed. In the far zone of a source, the IP of rocks led to quasi-wave phenomena. They produced rapid fluctuations of frequency and transient sounding curves (interference phenomena, multireflections in polarizable layers). In the case of transient sounding in the near zone of a source quasistatic distortions prevailed, caused by the counter electromotive force arising in polarizable layers which may lead to strong change in transient curves. In same case in quasiwave and quasistatic phenomena made EM sounding curves non-interpretable in the class of quasistationary curves over non-dispersive sections. On the other hand, they could increase the resolution and depth of investigation of EM sounding. This was confirmed by an experience of 'high-resolution' electroprospectring in Russia. The problem of interpretation of EM sounding data in polarizable sections is non unique. To achieve uniqueness it is probably to complement them by sounding of other type

  2. High resolution electromagnetic methods and low frequency dispersion of rock conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Svetov, B.S.; Ageev, V.V. [Geoelectromagnetic Research Institute, Institute of Physics of the Earth, RAS, Moscow (Russian Federation)

    1999-08-01

    The influence of frequency dispersion of conductivity (induced polarization) of rocks on the results of electromagnetic (EM) sounding was studied on the basis of calculation of electric field of vertical magnetic dipole above horizontally layered polarizable sections. Frequency dispersion was approximated by the Debye formula. Polarizable homogeneous half space, two, three and multilayered section were analyzed in frequency and tim domains. The calculations for different values of charge ability and time constants of polarization were performed. In the far zone of a source, the IP of rocks led to quasi-wave phenomena. They produced rapid fluctuations of frequency and transient sounding curves (interference phenomena, multireflections in polarizable layers). In the case of transient sounding in the near zone of a source quasistatic distortions prevailed, caused by the counter electromotive force arising in polarizable layers which may lead to strong change in transient curves. In same case in quasi wave and quasistatic phenomena made Em sounding curves non-interpretable in the class of quasistationary curves over non-dispersive sections. On the other hand, they could increase the resolution and depth of investigation of Em sounding. This was confirmed by an experience of 'high-resolution' electroprospectring in Russia. The problem of interpretation of EM sounding data in polarizable sections is non unique. To achieve uniqueness it is probably to complement them by sounding of other type.

  3. Pneumonia: high-resolution CT findings in 114 patients

    Energy Technology Data Exchange (ETDEWEB)

    Reittner, Pia [Department of Radiology, Vancouver Hospital and Health Sciences Center, 855 W. 12th Ave., Vancouver, BC (Canada); Department of Radiology, Karl Franzens University and University Hospital Graz, Auenbruggerplatz 9, 8036 Graz (Austria); Ward, Suzanne; Heyneman, Laura; Mueller, Nestor L. [Department of Radiology, Vancouver Hospital and Health Sciences Center, 855 W. 12th Ave., Vancouver, BC (Canada); Johkoh, Takeshi [Department of Radiology, Osaka University Medical School, 2-2 Yamadaoka, Suita, Osaka 565-0825 (Japan)

    2003-03-01

    The objective of the present study was to assess the high-resolution CT appearances of different types of pneumonia. The high-resolution CT scans obtained in 114 patients (58 immunocompetent, 59 immunocompromised) with bacterial, Mycoplasma pneumoniae, viral, fungal, and Pneumocystis carinii pneumonias were analyzed retrospectively by two independent observers for presence, pattern, and distribution of abnormalities. Areas of air-space consolidation were not detected in patients with viral pneumonia and were less frequently seen in patients with Pneumocystis carinii pneumonia (2 of 22 patients, 9%) than in bacterial (30 of 35, 85%), Mycoplasma pneumoniae (22 of 28, 79%), and fungal pneumonias (15 of 20, 75%; p<0.01). There was no significant difference in the prevalence or distribution of consolidation between bacterial, Mycoplasma pneumoniae, and fungal pneumonias. Extensive symmetric bilateral areas of ground-glass attenuation were present in 21 of 22 (95%) patients with Pneumocystis carinii pneumonia and were not seen in other pneumonias except in association with areas of consolidation and nodules. Centrilobular nodules were present less commonly in bacterial pneumonia (6 of 35 patients, 17%) than in Mycoplasma pneumoniae (24 of 28, 96%), viral (7 of 9, 78%), or fungal (12 of 20, 92%) pneumonia (p<0.01). Except for Pneumocystis carinii pneumonia and Mycoplasma pneumoniae pneumonia, which often have a characteristic appearance, high-resolution CT is of limited value in the differential diagnosis of the various types of infective pneumonia. (orig.)

  4. High-resolution CT findings in Streptococcus milleri pulmonary infection

    International Nuclear Information System (INIS)

    Okada, F.; Ono, A.; Ando, Y.; Nakayama, T.; Ishii, H.; Hiramatsu, K.; Sato, H.; Kira, A.; Otabe, M.; Mori, H.

    2013-01-01

    Aim: To assess pulmonary high-resolution computed tomography (CT) findings in patients with acute Streptococcus milleri pulmonary infection. Materials and methods: Sixty consecutive patients with acute S. milleri pneumonia who had undergone high-resolution CT chest examinations between January 2004 and March 2010 were retrospectively identified. Twenty-seven patients with concurrent infections were excluded. The final study group comprised 33 patients (25 men, 8 women; aged 20–88 years, mean 63.1 years) with S. milleri infection. The patients' clinical findings were assessed. Parenchymal abnormalities, enlarged lymph nodes, and pleural effusion were evaluated on high-resolution CT. Results: Underlying conditions included malignancy (n = 15), a smoking habit (n = 11), and diabetes mellitus (n = 8). CT images of all patients showed abnormal findings, including ground-glass opacity (n = 24), bronchial wall thickening (n = 23), consolidation (n = 17), and cavities (n = 7). Pleural effusion was found in 18 patients, and complex pleural effusions were found in seven patients. Conclusion: Pulmonary infection caused by S. milleri was observed mostly in male patients with underlying conditions such as malignancy or a smoking habit. The CT findings in patients with S. milleri consisted mainly of ground-glass opacity, bronchial wall thickening, pleural effusions, and cavities

  5. Adaptive optics with pupil tracking for high resolution retinal imaging.

    Science.gov (United States)

    Sahin, Betul; Lamory, Barbara; Levecq, Xavier; Harms, Fabrice; Dainty, Chris

    2012-02-01

    Adaptive optics, when integrated into retinal imaging systems, compensates for rapidly changing ocular aberrations in real time and results in improved high resolution images that reveal the photoreceptor mosaic. Imaging the retina at high resolution has numerous potential medical applications, and yet for the development of commercial products that can be used in the clinic, the complexity and high cost of the present research systems have to be addressed. We present a new method to control the deformable mirror in real time based on pupil tracking measurements which uses the default camera for the alignment of the eye in the retinal imaging system and requires no extra cost or hardware. We also present the first experiments done with a compact adaptive optics flood illumination fundus camera where it was possible to compensate for the higher order aberrations of a moving model eye and in vivo in real time based on pupil tracking measurements, without the real time contribution of a wavefront sensor. As an outcome of this research, we showed that pupil tracking can be effectively used as a low cost and practical adaptive optics tool for high resolution retinal imaging because eye movements constitute an important part of the ocular wavefront dynamics.

  6. Pneumonia: high-resolution CT findings in 114 patients

    International Nuclear Information System (INIS)

    Reittner, Pia; Ward, Suzanne; Heyneman, Laura; Mueller, Nestor L.; Johkoh, Takeshi

    2003-01-01

    The objective of the present study was to assess the high-resolution CT appearances of different types of pneumonia. The high-resolution CT scans obtained in 114 patients (58 immunocompetent, 59 immunocompromised) with bacterial, Mycoplasma pneumoniae, viral, fungal, and Pneumocystis carinii pneumonias were analyzed retrospectively by two independent observers for presence, pattern, and distribution of abnormalities. Areas of air-space consolidation were not detected in patients with viral pneumonia and were less frequently seen in patients with Pneumocystis carinii pneumonia (2 of 22 patients, 9%) than in bacterial (30 of 35, 85%), Mycoplasma pneumoniae (22 of 28, 79%), and fungal pneumonias (15 of 20, 75%; p<0.01). There was no significant difference in the prevalence or distribution of consolidation between bacterial, Mycoplasma pneumoniae, and fungal pneumonias. Extensive symmetric bilateral areas of ground-glass attenuation were present in 21 of 22 (95%) patients with Pneumocystis carinii pneumonia and were not seen in other pneumonias except in association with areas of consolidation and nodules. Centrilobular nodules were present less commonly in bacterial pneumonia (6 of 35 patients, 17%) than in Mycoplasma pneumoniae (24 of 28, 96%), viral (7 of 9, 78%), or fungal (12 of 20, 92%) pneumonia (p<0.01). Except for Pneumocystis carinii pneumonia and Mycoplasma pneumoniae pneumonia, which often have a characteristic appearance, high-resolution CT is of limited value in the differential diagnosis of the various types of infective pneumonia. (orig.)

  7. Toward high-resolution NMR spectroscopy of microscopic liquid samples

    Energy Technology Data Exchange (ETDEWEB)

    Butler, Mark C.; Mehta, Hardeep S.; Chen, Ying; Reardon, Patrick N.; Renslow, Ryan S.; Khbeis, Michael; Irish, Duane; Mueller, Karl T.

    2017-01-01

    A longstanding limitation of high-resolution NMR spectroscopy is the requirement for samples to have macroscopic dimensions. Commercial probes, for example, are designed for volumes of at least 5 mL, in spite of decades of work directed toward the goal of miniaturization. Progress in miniaturizing inductive detectors has been limited by a perceived need to meet two technical requirements: (1) minimal separation between the sample and the detector, which is essential for sensitivity, and (2) near-perfect magnetic-field homogeneity at the sample, which is typically needed for spectral resolution. The first of these requirements is real, but the second can be relaxed, as we demonstrate here. By using pulse sequences that yield high-resolution spectra in an inhomogeneous field, we eliminate the need for near-perfect field homogeneity and the accompanying requirement for susceptibility matching of microfabricated detector components. With this requirement removed, typical imperfections in microfabricated components can be tolerated, and detector dimensions can be matched to those of the sample, even for samples of volume << 5 uL. Pulse sequences that are robust to field inhomogeneity thus enable small-volume detection with optimal sensitivity. We illustrate the potential of this approach to miniaturization by presenting spectra acquired with a flat-wire detector that can easily be scaled to subnanoliter volumes. In particular, we report high-resolution NMR spectroscopy of an alanine sample of volume 500 pL.

  8. OECD/DOE/CEA VVER-1000 Coolant Transient Benchmark. Summary Record of the Fourth Workshop (V100-CT4)

    International Nuclear Information System (INIS)

    2006-01-01

    The overall objective of the VVER-1000 coolant transient (V1000CT) benchmark is to assess computer codes used in the safety analysis of VVER power plants, specifically for their use in analysis of reactivity transients in a VVER-1000. The V1000CT benchmark consists of two phases: V1000CT-1 is a simulation of the switching on of one main coolant pump (MCP) when the other three MCPs are in operation, and V1000CT-2 concerns calculation of coolant mixing tests and main steam line break (MSLB) scenarios. Each of the two phases contains three exercises. The reference problem chosen for simulation in Phase 1 is a MCP switching on when the other three main coolant pumps are in operation in a VVER-1000. This event is characterized by rapid increase in the flow through the core resulting in a coolant temperature decrease, which is spatially dependent. This leads to insertion of spatially distributed positive reactivity due to the modelled feedback mechanisms and non-symmetric power distribution. Simulation of the transient requires evaluation of core response from a multi-dimensional perspective (coupled three-dimensional neutronics/core thermal-hydraulics) supplemented by a one-dimensional simulation of the remainder of the reactor coolant system. Three exercises are defined in the framework of Phase 1: a) Exercise 1 - Point kinetics plant simulation; b) Exercise 2 - Coupled 3-D neutronics/core thermal-hydraulics response evaluation; c) Exercise 3 - Best-estimate coupled 3-D core/plant system transient modelling. In addition to the measured (experiment) scenario, extreme calculation scenarios were defined in the frame of Exercise 3 for better testing 3-D neutronics/thermal-hydraulics techniques. The proposals concerned: rod ejection simulations with scram set points at two different power levels. Since the previous coupled code benchmarks indicated that further development of the mixing computation models in the integrated codes is necessary, a coolant mixing experiment and

  9. Upper Campanian–Maastrichtian nannofossil biostratigraphy and high-resolution carbon-isotope stratigraphy of the Danish Basin

    DEFF Research Database (Denmark)

    Thibault, Nicolas Rudolph; Harlou, Rikke; Schovsbo, Niels

    2012-01-01

    High-resolution carbon isotope stratigraphy of the upper Campanian – Maastrichtian is recorded in the Boreal Realm from a total of 1968 bulk chalk samples of the Stevns-1 core, eastern Denmark. Isotopic trends are calibrated by calcareous nannofossil bio-events and are correlated with a lower...

  10. Brain Network Analysis from High-Resolution EEG Signals

    Science.gov (United States)

    de Vico Fallani, Fabrizio; Babiloni, Fabio

    lattice and a random structure. Such a model has been designated as "small-world" network in analogy with the concept of the small-world phenomenon observed more than 30 years ago in social systems. In a similar way, many types of functional brain networks have been analyzed according to this mathematical approach. In particular, several studies based on different imaging techniques (fMRI, MEG and EEG) have found that the estimated functional networks showed small-world characteristics. In the functional brain connectivity context, these properties have been demonstrated to reflect an optimal architecture for the information processing and propagation among the involved cerebral structures. However, the performance of cognitive and motor tasks as well as the presence of neural diseases has been demonstrated to affect such a small-world topology, as revealed by the significant changes of L and C. Moreover, some functional brain networks have been mostly found to be very unlike the random graphs in their degree-distribution, which gives information about the allocation of the functional links within the connectivity pattern. It was demonstrated that the degree distributions of these networks follow a power-law trend. For this reason those networks are called "scale-free". They still exhibit the small-world phenomenon but tend to contain few nodes that act as highly connected "hubs". Scale-free networks are known to show resistance to failure, facility of synchronization and fast signal processing. Hence, it would be important to see whether the scaling properties of the functional brain networks are altered under various pathologies or experimental tasks. The present Chapter proposes a theoretical graph approach in order to evaluate the functional connectivity patterns obtained from high-resolution EEG signals. In this way, the "Brain Network Analysis" (in analogy with the Social Network Analysis that has emerged as a key technique in modern sociology) represents an

  11. The coupling of high-speed high resolution experimental data and LES through data assimilation techniques

    Science.gov (United States)

    Harris, S.; Labahn, J. W.; Frank, J. H.; Ihme, M.

    2017-11-01

    Data assimilation techniques can be integrated with time-resolved numerical simulations to improve predictions of transient phenomena. In this study, optimal interpolation and nudging are employed for assimilating high-speed high-resolution measurements obtained for an inert jet into high-fidelity large-eddy simulations. This experimental data set was chosen as it provides both high spacial and temporal resolution for the three-component velocity field in the shear layer of the jet. Our first objective is to investigate the impact that data assimilation has on the resulting flow field for this inert jet. This is accomplished by determining the region influenced by the data assimilation and corresponding effect on the instantaneous flow structures. The second objective is to determine optimal weightings for two data assimilation techniques. The third objective is to investigate how the frequency at which the data is assimilated affects the overall predictions. Graduate Research Assistant, Department of Mechanical Engineering.

  12. Very high resolution UV and x-ray spectroscopy and imagery of solar active regions. Final report

    International Nuclear Information System (INIS)

    Bruner, M.; Brown, W.A.; Haisch, B.M.

    1987-01-01

    A scientific investigation of the physics of the solar atmosphere, which uses the techniques of high resolution soft x-ray spectroscopy and high resolution UV imagery, is described. The experiments were conducted during a series of three sounding rocket flights. All three flights yielded excellent images in the UV range, showing unprecedented spatial resolution. The second flight recorded the x-ray spectrum of a solar flare, and the third that of an active region. A normal incidence multi-layer mirror was used during the third flight to make the first astronomical x-ray observations using this new technique

  13. Performance of short ECG recordings twice daily to detect paroxysmal atrial fibrillation in stroke and transient ischemic attack patients

    DEFF Research Database (Denmark)

    Poulsen, Mai Bang; Binici, Zeynep; Domínguez, Helena

    2017-01-01

    Aims Prolonged cardiac monitoring after stroke is recommended though there is no consensus on optimal methods. Short-term ECG recordings with a "thumb-ECG" device have shown promising preliminary results regarding effectiveness and cost benefit. We aimed to examine the performance of thumb...... methods was poor and the trial was not powered to detect a minor difference between the devices. The inter-observer agreement for the thumb-ECG was substantial. www.clinicalTrials.gov UI: NCT02261766....

  14. Hybrid Adaptive Filter development for the minimisation of transient fluctuations superimposed on electrotelluric field recordings mainly by magnetic storms

    Directory of Open Access Journals (Sweden)

    A. Konstantaras

    2006-01-01

    Full Text Available The method of Hybrid Adaptive Filtering (HAF aims to recover the recorded electric field signals from anomalies of magnetotelluric origin induced mainly by magnetic storms. An adaptive filter incorporating neuro-fuzzy technology has been developed to remove any significant distortions from the equivalent magnetic field signal, as retrieved from the original electric field signal by reversing the magnetotelluric method. Testing with further unseen data verifies the reliability of the model and demonstrates the effectiveness of the HAF method.

  15. Changes in Moisture Flux Over the Tibetan Plateau During 1979-2011: Insights from a High Resolution Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Yanhong; Leung, Lai-Yung R.; Zhang, Yongxin; Cuo, Lan

    2015-05-01

    Net precipitation (precipitation minus evapotranspiration, P-E) changes from a high resolution regional climate simulation and its reanalysis forcing are analyzed over the Tibet Plateau (TP) and compared to the global land data assimilation system (GLDAS) product. The mechanism behind the P-E changes is explored by decomposing the column integrated moisture flux convergence into thermodynamic, dynamic, and transient eddy components. High-resolution climate simulation improves the spatial pattern of P-E changes over the best available global reanalysis. Improvement in simulating precipitation changes at high elevations contributes dominantly to the improved P-E changes. High-resolution climate simulation also facilitates new and substantial findings regarding the role of thermodynamics and transient eddies in P-E changes reflected in observed changes in major river basins fed by runoff from the TP. The analysis revealed the contrasting convergence/divergence changes between the northwestern and southeastern TP and feedback through latent heat release as an important mechanism leading to the mean P-E changes in the TP.

  16. PEPSI, the High-Resolution Optical-IR Spectrograph for the LBT

    Science.gov (United States)

    Andersen, Michael; Strassmeier, Klaus; Hoffman, Axel; Woche, Manfred; Spano, Paolo

    PEPSI is a high resolution fibre feed optical-IR polarimetric echelle spectrograph for the Large Binocular Telescope (LBT). PEPSI utilizes the two 8.4m LBT apertures to simultaneously record four polarization states at a resolution of 120.000. The extension of the coverage towards the IR is mainly motivated by the larger Zeeman splitting of IR lines, which would allow to study weaker/fainter magnetic structures on stars. The two optical arms, which also have an integral light mode with R up to 300.000, are under construction, while the IR arm is being designed.

  17. Observations of movement dynamics of flying insects using high resolution lidar

    DEFF Research Database (Denmark)

    Kirkeby, Carsten Thure; Wellenreuther, Maren; Brydegaard, Mikkel

    2016-01-01

    insects (wing size cross-section) moved across the field and clustered near the light trap around 22:00 local time, while larger insects (wing size >2.5 mm2 in cross-section) were most abundant near the lidar beam before 22:00 and then moved towards the light trap between 22:00 and 23:30. We......Insects are fundamental to ecosystem functioning and biodiversity, yet the study of insect movement, dispersal and activity patterns remains a challenge. Here we present results from a novel high resolution laser-radar (lidar) system for quantifying flying insect abundance recorded during one...

  18. A high-resolution multiwire area detector for X-ray scattering

    Energy Technology Data Exchange (ETDEWEB)

    Faruqi, A R; Andrews, H [Medical Research Council, Cambridge (UK). Lab. of Molecular Biology

    1989-11-10

    A high-resolution multiwire area detector has been developed for recording X-ray scattering from biological specimens. The detector is 100x100 mm{sup 2} and, under the present operating conditions, has a spatial resolution of about 250 {mu}m in both directions. The detector is set up on a double-mirror focusing camera on a rotating anode X-ray generator and has been used in a number of small-angle experiments, two of which are described in this paper. (orig.).

  19. High resolution measurements and study of the neutron inelastic scattering reaction on 56Fe

    International Nuclear Information System (INIS)

    Dupont, E.

    1998-01-01

    High resolution measures of neutrons inelastic scattering cross section, have been performed on 56 Fe from 862 KeV to 3 MeV. The time of flight method has been used on the GELINA source of the IRMM in Geel (Belgium). Four barium fluoride scintillators, placed around the samples, recorded the gamma rays emissions coming from the iron and the boron. A study of the correlations between the partial elastic and inelastic lengths has been performed taking into account first transmission measures realized at Geel. (A.L.B.)

  20. High resolution solar observations from first principles to applications

    Science.gov (United States)

    Verdoni, Angelo P.

    2009-10-01

    The expression "high-resolution observations" in Solar Physics refers to the spatial, temporal and spectral domains in their entirety. High-resolution observations of solar fine structure are a necessity to answer many of the intriguing questions related to solar activity. However, a researcher building instruments for high-resolution observations has to cope with the fact that these three domains often have diametrically opposed boundary conditions. Many factors have to be considered in the design of a successful instrument. Modern post-focus instruments are more closely linked with the solar telescopes that they serve than in past. In principle, the quest for high-resolution observations already starts with the selection of the observatory site. The site survey of the Advanced Technology Solar Telescope (ATST) under the stewardship of the National Solar Observatory (NSO) has identified Big Bear Solar Observatory (BBSO) as one of the best sites for solar observations. In a first step, the seeing characteristics at BBSO based on the data collected for the ATST site survey are described. The analysis will aid in the scheduling of high-resolution observations at BBSO as well as provide useful information concerning the design and implementation of a thermal control system for the New Solar Telescope (NST). NST is an off-axis open-structure Gregorian-style telescope with a 1.6 m aperture. NST will be housed in a newly constructed 5/8-sphere ventilated dome. With optics exposed to the surrounding air, NST's open-structure design makes it particularly vulnerable to the effects of enclosure-related seeing. In an effort to mitigate these effects, the initial design of a thermal control system for the NST dome is presented. The goal is to remediate thermal related seeing effects present within the dome interior. The THermal Control System (THCS) is an essential component for the open-telescope design of NST to work. Following these tasks, a calibration routine for the

  1. A subspace approach to high-resolution spectroscopic imaging.

    Science.gov (United States)

    Lam, Fan; Liang, Zhi-Pei

    2014-04-01

    To accelerate spectroscopic imaging using sparse sampling of (k,t)-space and subspace (or low-rank) modeling to enable high-resolution metabolic imaging with good signal-to-noise ratio. The proposed method, called SPectroscopic Imaging by exploiting spatiospectral CorrElation, exploits a unique property known as partial separability of spectroscopic signals. This property indicates that high-dimensional spectroscopic signals reside in a very low-dimensional subspace and enables special data acquisition and image reconstruction strategies to be used to obtain high-resolution spatiospectral distributions with good signal-to-noise ratio. More specifically, a hybrid chemical shift imaging/echo-planar spectroscopic imaging pulse sequence is proposed for sparse sampling of (k,t)-space, and a low-rank model-based algorithm is proposed for subspace estimation and image reconstruction from sparse data with the capability to incorporate prior information and field inhomogeneity correction. The performance of the proposed method has been evaluated using both computer simulations and phantom studies, which produced very encouraging results. For two-dimensional spectroscopic imaging experiments on a metabolite phantom, a factor of 10 acceleration was achieved with a minimal loss in signal-to-noise ratio compared to the long chemical shift imaging experiments and with a significant gain in signal-to-noise ratio compared to the accelerated echo-planar spectroscopic imaging experiments. The proposed method, SPectroscopic Imaging by exploiting spatiospectral CorrElation, is able to significantly accelerate spectroscopic imaging experiments, making high-resolution metabolic imaging possible. Copyright © 2014 Wiley Periodicals, Inc.

  2. Landslide detection using very high-resolution satellite imageries

    Science.gov (United States)

    Suga, Yuzo; Konishi, Tomohisa

    2012-10-01

    The heavy rain induced by the 12th typhoon caused landslide disaster at Kii Peninsula in the middle part of Japan. We propose a quick response method for landslide disaster mapping using very high resolution (VHR) satellite imageries. Especially, Synthetic Aperture Radar (SAR) is effective because it has the capability of all weather and day/night observation. In this study, multi-temporal COSMO-SkyMed imageries were used to detect the landslide areas. It was difficult to detect the landslide areas using only backscatter change pattern derived from pre- and post-disaster COSMOSkyMed imageries. Thus, the authors adopted a correlation analysis which the moving window was selected for the correlation coefficient calculation. Low value of the correlation coefficient reflects land cover change between pre- and post-disaster imageries. This analysis is effective for the detection of landslides using SAR data. The detected landslide areas were compared with the area detected by EROS-B high resolution optical image. In addition, we have developed 3D viewing system for geospatial visualizing of the damaged area using these satellite image data with digital elevation model. The 3D viewing system has the performance of geographic measurement with respect to elevation height, area and volume calculation, and cross section drawing including landscape viewing and image layer construction using a mobile personal computer with interactive operation. As the result, it was verified that a quick response for the detection of landslide disaster at the initial stage could be effectively performed using optical and SAR very high resolution satellite data by means of 3D viewing system.

  3. Proceedings of the workshop on high resolution computed microtomography (CMT)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-01

    The purpose of the workshop was to determine the status of the field, to define instrumental and computational requirements, and to establish minimum specifications required by possible users. The most important message sent by implementers was the remainder that CMT is a tool. It solves a wide spectrum of scientific problems and is complementary to other microscopy techniques, with certain important advantages that the other methods do not have. High-resolution CMT can be used non-invasively and non-destructively to study a variety of hierarchical three-dimensional microstructures, which in turn control body function. X-ray computed microtomography can also be used at the frontiers of physics, in the study of granular systems, for example. With high-resolution CMT, for example, three-dimensional pore geometries and topologies of soils and rocks can be obtained readily and implemented directly in transport models. In turn, these geometries can be used to calculate fundamental physical properties, such as permeability and electrical conductivity, from first principles. Clearly, use of the high-resolution CMT technique will contribute tremendously to the advancement of current R and D technologies in the production, transport, storage, and utilization of oil and natural gas. It can also be applied to problems related to environmental pollution, particularly to spilling and seepage of hazardous chemicals into the Earth's subsurface. Applications to energy and environmental problems will be far-ranging and may soon extend to disciplines such as materials science--where the method can be used in the manufacture of porous ceramics, filament-resin composites, and microelectronics components--and to biomedicine, where it could be used to design biocompatible materials such as artificial bones, contact lenses, or medication-releasing implants. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  4. Geological survey by high resolution electrical survey on granite areas

    International Nuclear Information System (INIS)

    Sugimoto, Yoshihiro; Yamada, Naoyuki

    2002-03-01

    As an Integral part of the geological survey in 'The study of the regions ground water flow system' that we are carrying out with Tono Geoscience Center, we proved the relation between the uncontinuation structure such as lineament in the base rock and resistivity structure (resistivity distribution), for the purpose of that confirms the efficacy of the high resolution electrical survey as geological survey, we carried out high resolution electrical survey on granite area. We obtained the following result, by the comparison of resistivity distribution with established geological survey, lineament analysis and investigative drilling. 1. The resistivity structure of this survey area is almost able to classify it into the following four range. 1) the low resistivity range of 50-800 Ωm, 2) The resistivity range like the middle of 200-2000 Ωm, 3) The high resistivity range of 2000 Ωm over, 4) The low resistivity range of depth of the survey line 400-550 section. 2. The low resistivity range of 4) that correspond with the established geological data is not admitted. 3. It was confirmed that resistivity structure almost correspond to geological structure by the comparison with the established data. 4. The small-scale low resistivity area is admitted in the point equivalent to the lineament position of established. 5. We carried out it with the simulation method about the low resistivity range of 4). As a result, it understood that it has the possibility that the narrow ratio low resistivity area is shown as the wide ratio resistivity range in the analysis section. In the survey in this time, it is conceivable that the resistivity distribution with the possibility of the unhomogeneous and uncontinuation structure of the base rock is being shown conspicuously, the efficacy of the high resolution resistivity survey as geological survey on granite was shown. (author)

  5. High-resolution ultrasonography in assessing temporomandibular joint disc position.

    Science.gov (United States)

    Talmaceanu, Daniel; Lenghel, Lavinia Manuela; Bolog, Nicolae; Popa Stanila, Roxana; Buduru, Smaranda; Leucuta, Daniel Corneliu; Rotar, Horatiu; Baciut, Mihaela; Baciut, Grigore

    2018-02-04

    The purpose of this study was to determine the diagnostic value of high-resolution ultrasonography (US) in temporomandibular joint (TMJ) disc displacements. A number of 74 patients (148 TMJs) with signs and symptoms of TMJ disorders, according to the Research Diagnostic Criteria for Temporomandibular Disorders, were included in this study. All patients received US and magnetic resonance imaging (MRI) of both TMJs 1 to 5 days after the clinical examination. MRI examinations were performed using 1.5 T MRI equipment (Siemens Avanto, Siemens, Erlangen). Ultrasonographic examination was performed on a Hitachi EUB 8500 (Hitachi Medical Corp., Tokyo, Japan) scanner with L 54 M6.5-13 MHz linear transducer. MRI depicted 68 (45.95%) normal joints, 47 (31.76%) with disc displacement with reduction, 33 (22.3%) with disc displacement without reduction and 34 (22.97%) with degenerative changes. US detected 78 (52.7%) normal joints, 37 (25%) with disc displacement with reduction, 33 (22.3%) with disc displacement without reduction and 21 (14.19%) with degenerative changes. Compared to MRI, US showed a sensitivity of 93.1%, specificity of 87.88%, accuracy of 90.32%, a positive predictive value of 87.1% and a negative predictive value of 93.55% for overall diagnosis of disc displacement. The Youden index was 0.81. Based on our results, high-resolution ultrasonography showed high sensitivity, specificity and accuracy in the diagnosis of TMJ disc displacement. It could be a valuable imaging technique in assessing TMJ disc position. The diagnostic value of high-resolution ultrasonography depends strictly on the examiner's skills and on the equipment used.

  6. On temporal correlations in high-resolution frequency counting

    OpenAIRE

    Dunker, Tim; Hauglin, Harald; Rønningen, Ole Petter

    2016-01-01

    We analyze noise properties of time series of frequency data from different counting modes of a Keysight 53230A frequency counter. We use a 10 MHz reference signal from a passive hydrogen maser connected via phase-stable Huber+Suhner Sucoflex 104 cables to the reference and input connectors of the counter. We find that the high resolution gap-free (CONT) frequency counting process imposes long-term correlations in the output data, resulting in a modified Allan deviation that is characteristic...

  7. High Resolution Spectrometer (HRS) particle-identification system

    International Nuclear Information System (INIS)

    Pratt, J.C.; Spencer, J.E.; Whitten, C.A.

    1977-08-01

    The functions of the particle-identification system (PIDS) designed for the High Resolution Spectrometer facility (HRS) at LAMPF are described, together with the mechanical layout, counter hardware, and associated electronics. The system was designed for easy use and to be applicable to currently proposed experiments at HRS. The several strobe signals that can be generated correspond to different event types or characteristics, and logic configuration and timing can be remotely controlled by computer. Concepts of discrete pattern recognition and multidimensional, analog pulse discrimination are used to distinguish between different event types

  8. Computing with high-resolution upwind schemes for hyperbolic equations

    International Nuclear Information System (INIS)

    Chakravarthy, S.R.; Osher, S.; California Univ., Los Angeles)

    1985-01-01

    Computational aspects of modern high-resolution upwind finite-difference schemes for hyperbolic systems of conservation laws are examined. An operational unification is demonstrated for constructing a wide class of flux-difference-split and flux-split schemes based on the design principles underlying total variation diminishing (TVD) schemes. Consideration is also given to TVD scheme design by preprocessing, the extension of preprocessing and postprocessing approaches to general control volumes, the removal of expansion shocks and glitches, relaxation methods for implicit TVD schemes, and a new family of high-accuracy TVD schemes. 21 references

  9. Achieving High Resolution Timer Events in Virtualized Environment.

    Science.gov (United States)

    Adamczyk, Blazej; Chydzinski, Andrzej

    2015-01-01

    Virtual Machine Monitors (VMM) have become popular in different application areas. Some applications may require to generate the timer events with high resolution and precision. This however may be challenging due to the complexity of VMMs. In this paper we focus on the timer functionality provided by five different VMMs-Xen, KVM, Qemu, VirtualBox and VMWare. Firstly, we evaluate resolutions and precisions of their timer events. Apparently, provided resolutions and precisions are far too low for some applications (e.g. networking applications with the quality of service). Then, using Xen virtualization we demonstrate the improved timer design that greatly enhances both the resolution and precision of achieved timer events.

  10. High resolution spectroscopy of six new extreme helium stars

    Science.gov (United States)

    Heber, U.; Jones, G.; Drilling, J. S.

    1986-01-01

    High resolution spectra of six newly discovered extreme helium stars are presented. LSS 5121 is shown to be a spectroscopical twin of the hot extreme helium star HD 160641. A preliminary LTE analysis of LSS 3184 yielded an effective temperature of 22,000 K and a surface gravity of log g = 3.2. Four stars form a new subgroup, classified by sharp-lined He I spectra and pronounced O II spectra, and it is conjectured that these lie close to the Eddington limit. The whole group of extreme helium stars apparently is inhomogeneous with respect to luminosity to mass ratio and chemical composition.

  11. High resolution laser spectroscopy as a diagnostic tool in beams

    International Nuclear Information System (INIS)

    Bergmann, K.; Hefter, U.; Hering, P.

    1977-01-01

    The combination of high resolution laser spectroscopy with the technique of molecular beams allows a very detailed beam research since molecules or atoms in specific quantum states can be sampled yielding previously unavailable sources of data. In these experiments a Na/Na 2 beam emerges from a 0.2 mm nozzle and is collimated by a 2 mm wide slit 50 cm downstream. To probe the molecules a single mode Ar + -laser was used which can be tuned within the gain profile of the laser line (8 GHz) to several transitions between specific levels in the ground state and second electronically excited state of the Na 2 molecule. (Auth.)

  12. High resolution skin colorimetry, strain mapping and mechanobiology.

    Science.gov (United States)

    Devillers, C; Piérard-Franchimont, C; Schreder, A; Docquier, V; Piérard, G E

    2010-08-01

    Skin colours are notoriously different between individuals. They are governed by ethnicities and phototypes, and further influenced by a variety of factors including photoexposures and sustained mechanical stress. Indeed, mechanobiology is a feature affecting the epidermal melanization. High-resolution epiluminescence colorimetry helps in deciphering the effects of forces generated by Langer's lines or relaxed skin tension lines on the melanocyte activity. The same procedure shows a prominent laddering pattern of melanization in striae distensae contrasting with the regular honeycomb pattern in the surrounding skin.

  13. Diesel characterization by high-resolution mass spectrometry - gas chromatography

    International Nuclear Information System (INIS)

    Baldrich, C.A

    1998-01-01

    High-resolution mass spectrometry-gas chromatography is combined with the HC22 method in order to obtain detailed information about the chemical composition of diesel and the distribution of different compound types in terms of its final boiling temperature from a single analysis. The total time elapsed from sample injection and signal processing to obtain final results is 90 minutes. This fact makes this methodology a new and very important tool for the decision making process concerning the most suitable final boiling temperature and the type of treatment of the product in order to obtain diesel that fulfills the international standards. The consistency and repeatability of the experimental results are demonstrated

  14. New detector developments for high resolution positron emission tomography

    International Nuclear Information System (INIS)

    Ziegler, S.I.; Pichler, B.; Lorenz, E.

    1998-01-01

    The strength of quantitative, functional imaging using positron emission tomography, specially in small animals, is limited due to the spatial resolution. Therefore, various tomograph designs employing new scintillators, light sensors, or coincidence electronic are investigated to improve resolution without losses in sensitivity. Luminous scintillators with short light decay time in combination with novel readout schemes using photomultipliers or semiconductor detectors are currently tested by several groups and are implemented in tomographs for small animals. This review summarises the state of development in high resolution positron emission tomography with a detailed description of a system incorporating avalanche photodiode arrays and small scintillation crystals. (orig.) [de

  15. High resolution upgrade of the ATF damping ring BPM system

    International Nuclear Information System (INIS)

    Terunuma, N.; Urakawa, J.; Frisch, J.; May, J.; McCormick, D.; Nelson, J.; Seryi, A.; Smith, T.; Woodley, M.; Briegel, C.; Dysert, R.

    2008-01-01

    A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring has been accomplished in its first stage, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R and D effort. The upgrade consists of a high resolution, high reproducibility read-out system, based on analog and digital downconversion techniques, digital signal processing, and also tests a new automatic gain error correction schema. The technical concept and realization, as well as preliminary results of beam studies are presented

  16. High-resolution neutron-diffraction measurements to 8 kbar

    Science.gov (United States)

    Bull, C. L.; Fortes, A. D.; Ridley, C. J.; Wood, I. G.; Dobson, D. P.; Funnell, N. P.; Gibbs, A. S.; Goodway, C. M.; Sadykov, R.; Knight, K. S.

    2017-10-01

    We describe the capability to measure high-resolution neutron powder diffraction data to a pressure of at least 8 kbar. We have used the HRPD instrument at the ISIS neutron source and a piston-cylinder design of pressure cell machined from a null-scattering titanium zirconium alloy. Data were collected under hydrostatic conditions from an elpasolite perovskite La?NiMnO?; by virtue of a thinner cell wall on the incident-beam side of the cell, it was possible to obtain data in the instrument's highest resolution back-scattering detector banks up to a maximum pressure of 8.5 kbar.

  17. Diagnosis of cholesteatoma by high resolution computed tomography

    International Nuclear Information System (INIS)

    Kakitsubata, Yousuke; Kakitsubata, Sachiko; Ogata, Noboru; Asada, Keiko; Watanabe, Katsushi; Tohno, Tetsuya; Makino, Kohji

    1988-01-01

    Three normal volunteers and 57 patients with cholesteatoma were examined by high resolution computed tomography. Serial sections were made through the temporal bone at the nasaly inclined position of 30 degree to the orbitomeatal line (semiaxial plane ; SAP). The findings of temporal bone structures in normal subjects were evaluated in SAP and axial plane (OM). Although the both planes showed good visualization, SAP showed both the eustachian tube and tympanic cavity in one slice. In cholesteatoma soft tissue masses in the tympanic cavity, mastoid air cells and Eustachian tube were demonstrated clearly by SAP. (author)

  18. High resolution Moessbauer spectroscopy with 67Zn in metallic systems

    International Nuclear Information System (INIS)

    Potzel, W.

    1985-01-01

    Moessbauer experiments on metallic systems are described where the high resolution 93.3 keV resonance in 67 Zn is used. In the first part, the Cu-Zn alloy system is investigated and the high energy resolution of this Moessbauer transition is employed to determine small changes of the s-electron density at the 67 Zn nucleus when the Zn concentration is changed. In the second part, Zn metal is taken as an example to demonstrate that the 93.3 keV transition is also extremely sensitive to small changes of lattice dynamical effects. 7 refs., 18 figs. (author)

  19. Evaluation of high-resolution CT after tympanoplasty

    International Nuclear Information System (INIS)

    Torizuka, T.; Hayakawa, K.; Sato, Y.; Tanaka, F.; Okuno, Y.

    1991-01-01

    This paper reports on the condition of the middle ear cavity following tympanoplasty which is always of great interest to radiologists and otosurgeons. This study consisted of 21 patients who had various types of tympanoplasty (types I-IV) for chronic otitis media and cholesteatoma by using high-resolution CT (HRCT). HRCT following tympanoplasty was a valuable method for assessing the middle ear aeration and the state of ossicular reconstruction, including stapes prosthesis, although in some cases of soft-tissue mass in the middle ear it was necessary to correlate with clinical findings in order to differentiate between granulation and recurrence

  20. High resolution X-ray spectroscopy of thermal plasmas

    International Nuclear Information System (INIS)

    Canizares, C.R.

    1990-01-01

    This paper concentrates on reviewing highlights of the Focal Plane Crystal Spectrometer (FPCS) results on thermal plasmas, particularly supernova remnants (SNRs) and clusters of galaxies from the Einstein observatory. During Einstein's short but happy life, we made over 400 observations with the FPCS of 40 different objects. Three quarters of these were objects in which the emission was primarily from optically thin thermal plasma, primarily supernova remnants (SNRs) and clusters of galaxies. Thermal plasmas provide an excellent illustration of how spectral data, particularly high resolution spectral data, can be an important tool for probing the physical properties of astrophysical objects. (author)

  1. High-resolution CT of lymphoid interstitial pneumonia

    International Nuclear Information System (INIS)

    Vilgrain, V.; Frija, J.; Yana, C.; Couderc, L.J.; David, M.; Clauvel, J.P.; Laval-Jeantet, M.

    1989-01-01

    Three patients with lymphoid interstitial pneumonia (two HIV 1+ patients with chronic lymphadenopathic syndromes and one with a not-characterized autoimmune disease) have been studied with high-resolution computed tomography (HR-CT). This technique reveals septal lines, small reticulonodular opacities, polyhedral micronodular opacities, 'ground-glass' opacities and a dense, subpleural, curved broken line in one patient. The lesions dominate in the bases of the lungs. They are not characteristic for lymphoid interstitial pneumonia. If a patient presents with a chronic lymphadenopathic syndrome, the diagnosis of an opportunistic infection should not be automatically made, since the syndrome can be caused by lymphoid interstitial pneumonia [fr

  2. Intercalibration of the ZEUS high resolution and backing calorimeters

    International Nuclear Information System (INIS)

    Abramowicz, H.; Czyrkowski, H.; Derlicki, A.; Krzyzanowski, M.; Kudla, I.; Kusmierz, W.; Nowak, R.J.; Pawlak, J.M.; Rajca, A.; Stopczynski, A.; Walczak, R.; Zarnecki, A.F.; Kowalski, T.Z.

    1991-07-01

    We have studied the combined performance of two calorimeters, the high resolution uranium-scintillator prototype of the ZEUS forward calorimeter (FCAL), followed by a prototype of the coarser ZEUS backing calorimeter (BAC), made out of thick iron plates interleaved with planes of aluminium proportional chambers. The test results, obtained in an exposure of the calorimeter system to a hadron test beam at the CERN-SPS, show that the backing calorimeter does fulfil its role of recognizing the energy leaking out of the FCAL calorimeter. The measurement of this energy is feasible, if an appropriate calibration of the BAC calorimeter is performed. (orig.)

  3. High-resolution seismic wave propagation using local time stepping

    KAUST Repository

    Peter, Daniel

    2017-03-13

    High-resolution seismic wave simulations often require local refinements in numerical meshes to accurately capture e.g. steep topography or complex fault geometry. Together with explicit time schemes, this dramatically reduces the global time step size for ground-motion simulations due to numerical stability conditions. To alleviate this problem, local time stepping (LTS) algorithms allow an explicit time stepping scheme to adapt the time step to the element size, allowing nearoptimal time steps everywhere in the mesh. This can potentially lead to significantly faster simulation runtimes.

  4. High resolution resistivity measurements at the Down Ampney research site

    International Nuclear Information System (INIS)

    Hallam, J.R.; Jackson, P.D.; Rainsbury, M.; Raines, M.

    1991-01-01

    A new high resolution resistivity surveying method is described for fault detection and characterisation. The resolution is shown to be significantly higher than conventional apparent resistivity profiling when applied to geological discontinuities such as faults. Nominal fault locations have been determined to an accuracy of 0.5 m, as proven by drilling. Two dimensional profiling and image enhancement of the resulting 2-D data set indicated the possibility of subsidiary fractures and/or lateral changes within the clay to clay' fault zone. The increased resolution allows greater confidence to be placed on both the fault detection and lateral perturbations derived from processed resistance and resistivity images. (Author)

  5. High resolution SPM imaging of organic molecules with functionalized tips

    Czech Academy of Sciences Publication Activity Database

    Jelínek, Pavel

    2017-01-01

    Roč. 29, č. 34 (2017), 1-18, č. článku 343002. ISSN 0953-8984 R&D Projects: GA MŠk LM2015087; GA MŠk 8E15B010; GA ČR(CZ) GC14-16963J Grant - others:AV ČR(CZ) Praemium Academiae Institutional support: RVO:68378271 Keywords : atomic- force microscopy * scanning tunneling microscope * on-surface synthesis * single-molecule * AFM * STM * high resolution * molecules * surfaces Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 2.649, year: 2016

  6. Intercalibration of the ZEUS high resolution and backing calorimeters

    International Nuclear Information System (INIS)

    Abramowicz, H.; Czyrkowski, H.; Derlicki, A.; Krzyzanowski, M.; Kudla, I.; Kusmierz, W.; Nowak, R.J.; Pawlak, J.M.; Rajca, A.; Stopczynski, A.; Walczak, R.; Zarnecki, A.F.; Kowalski, T.Z.

    1992-01-01

    We have studied the combined performance of two calorimeters, the high resolution uranium-scintillator prototype of the ZEUS forward calorimeter (FCAL), followed by a prototype of the coarser ZEUS backing calorimeter (BAC), made out of thick iron plates interleaved with planes of aluminium proportional chambers. The test results, obtained in an exposure of the calorimeter system to a hadron test beam at the CERN SPS, show that the backing calorimeter does fulfil its role of recognizing the energy leaking out of the FCAL calorimeter. The measurement of this energy is feasible, if an appropriate calibration of the BAC calorimeter is performed. (orig.)

  7. High resolution X-ray spectroscopy in light antiprotonic atoms

    CERN Document Server

    Borchert, G L; Augsburger, M A; Castelli, C M; Chatellard, D; Egger, J P; El-Khoury, P; Elble, M; Gorke, H; Gotta, D; Hauser, P R; Indelicato, P J; Kirch, K; Lenz, S; Nelms, N; Rashid, K; Schult, O W B; Siems, T; Simons, L M

    2000-01-01

    At the LEAR facility, CERN, antiprotonic L alpha transitions in light elements have been investigated with a focussing crystal spectrometer. The high resolution of the experiment allowed for the first time to resolve in pH/pH the 2/sup 3/P/sub 0/ state from the close-lying states 2/sup 3/P/sub 2/, 2/sup 1/P/sub 1/, and 2/sup 3/P /sub 1/. In pD the corresponding transitions were found to be more than an order of magnitude broader. To a large extent the results for pH support the meson exchange model. (15 refs).

  8. A new omni-directional multi-camera system for high resolution surveillance

    Science.gov (United States)

    Cogal, Omer; Akin, Abdulkadir; Seyid, Kerem; Popovic, Vladan; Schmid, Alexandre; Ott, Beat; Wellig, Peter; Leblebici, Yusuf

    2014-05-01

    Omni-directional high resolution surveillance has a wide application range in defense and security fields. Early systems used for this purpose are based on parabolic mirror or fisheye lens where distortion due to the nature of the optical elements cannot be avoided. Moreover, in such systems, the image resolution is limited to a single image sensor's image resolution. Recently, the Panoptic camera approach that mimics the eyes of flying insects using multiple imagers has been presented. This approach features a novel solution for constructing a spherically arranged wide FOV plenoptic imaging system where the omni-directional image quality is limited by low-end sensors. In this paper, an overview of current Panoptic camera designs is provided. New results for a very-high resolution visible spectrum imaging and recording system inspired from the Panoptic approach are presented. The GigaEye-1 system, with 44 single cameras and 22 FPGAs, is capable of recording omni-directional video in a 360°×100° FOV at 9.5 fps with a resolution over (17,700×4,650) pixels (82.3MP). Real-time video capturing capability is also verified at 30 fps for a resolution over (9,000×2,400) pixels (21.6MP). The next generation system with significantly higher resolution and real-time processing capacity, called GigaEye-2, is currently under development. The important capacity of GigaEye-1 opens the door to various post-processing techniques in surveillance domain such as large perimeter object tracking, very-high resolution depth map estimation and high dynamicrange imaging which are beyond standard stitching and panorama generation methods.

  9. High resolution multiplexed functional imaging in live embryos (Conference Presentation)

    Science.gov (United States)

    Xu, Dongli; Zhou, Weibin; Peng, Leilei

    2017-02-01

    Fourier multiplexed fluorescence lifetime imaging (FmFLIM) scanning laser optical tomography (FmFLIM-SLOT) combines FmFLIM and Scanning laser optical tomography (SLOT) to perform multiplexed 3D FLIM imaging of live embryos. The system had demonstrate multiplexed functional imaging of zebrafish embryos genetically express Foster Resonant Energy Transfer (FRET) sensors. However, previous system has a 20 micron resolution because the focused Gaussian beam diverges quickly from the focused plane, makes it difficult to achieve high resolution imaging over a long projection depth. Here, we present a high-resolution FmFLIM-SLOT system with achromatic Bessel beam, which achieves 3 micron resolution in 3D deep tissue imaging. In Bessel-FmFLIM-SLOT, multiple laser excitation lines are firstly intensity modulated by a Michelson interferometer with a spinning polygon mirror optical delay line, which enables Fourier multiplexed multi-channel lifetime measurements. Then, a spatial light modulator and a prism are used to transform the modulated Gaussian laser beam to an achromatic Bessel beam. The achromatic Bessel beam scans across the whole specimen with equal angular intervals as sample rotated. After tomography reconstruction and the frequency domain lifetime analysis method, both the 3D intensity and lifetime image of multiple excitation-emission can be obtained. Using Bessel-FmFLIM-SLOT system, we performed cellular-resolution FLIM tomography imaging of live zebrafish embryo. Genetically expressed FRET sensors in these embryo will allow non-invasive observation of multiple biochemical processes in vivo.

  10. Development of a metallic magnetic calorimeter for high resolution spectroscopy

    International Nuclear Information System (INIS)

    Linck, M.

    2007-01-01

    In this thesis the development of a metallic magnetic calorimeter for high resolution detection of single x-ray quanta is described. The detector consists of an X-ray absorber and a paramagnetic temperature sensor. The raise in temperature of the paramagnetic sensor due to the absorption of a single X-ray is measured by the change in magnetization of the sensor using a low-noise SQUID magnetometer. The thermodynamic properties of the detector can be described by a theoretical model based on a mean field approximation. This allows for an optimization of the detector design with respect to signal size. The maximal archivable energy resolution is limited by thermodynamic energy fluctuations between absorber, heat bath and thermometer. An interesting field of application for a metallic magnetic calorimeter is X-ray astronomy and the investigation of X-ray emitting objects. Through high-resolution X-ray spectroscopy it is possible to obtain information about physical processes of even far distant objects. The magnetic calorimeter that was developed in this thesis has a metallic absorber with a quantum efficiency of 98% at 6 keV. The energy resolution of the magnetic calorimeter is EFWHM=2.7 eV at 5.9 keV. The deviation of the detector response from a linear behavior of the detector is only 0.8% at 5.9 keV. (orig.)

  11. Methylation-Sensitive High Resolution Melting (MS-HRM).

    Science.gov (United States)

    Hussmann, Dianna; Hansen, Lise Lotte

    2018-01-01

    Methylation-Sensitive High Resolution Melting (MS-HRM) is an in-tube, PCR-based method to detect methylation levels at specific loci of interest. A unique primer design facilitates a high sensitivity of the assays enabling detection of down to 0.1-1% methylated alleles in an unmethylated background.Primers for MS-HRM assays are designed to be complementary to the methylated allele, and a specific annealing temperature enables these primers to anneal both to the methylated and the unmethylated alleles thereby increasing the sensitivity of the assays. Bisulfite treatment of the DNA prior to performing MS-HRM ensures a different base composition between methylated and unmethylated DNA, which is used to separate the resulting amplicons by high resolution melting.The high sensitivity of MS-HRM has proven useful for detecting cancer biomarkers in a noninvasive manner in urine from bladder cancer patients, in stool from colorectal cancer patients, and in buccal mucosa from breast cancer patients. MS-HRM is a fast method to diagnose imprinted diseases and to clinically validate results from whole-epigenome studies. The ability to detect few copies of methylated DNA makes MS-HRM a key player in the quest for establishing links between environmental exposure, epigenetic changes, and disease.

  12. Exogenous lipoid pneumonia: high-resolution CT findings

    International Nuclear Information System (INIS)

    Lee, J.S.; Song, K.S.; Lim, T.H.; Im, J.G.; Seo, J.B.

    1999-01-01

    The aim of this study was to assess high-resolution computed tomography (HRCT) findings of exogenous lipoid pneumonia. High-resolution computed tomography was obtained in 25 patients with proven exogenous lipoid pneumonia resulting from aspiration of squalene (derived from shark liver oil). Diagnosis was based on biopsy (n = 9), bronchoalveolar lavage (n = 8), or sputum cytology and clinical findings (n = 8). The clinical history of taking squalene was confirmed in all patients. The CT findings were classified into three patterns: diffuse ground-glass opacity, consolidation, and interstitial abnormalities. Distribution of the abnormalities, duration of taking squalene, predisposing factors for aspiration, and route of administration were analyzed. Ten patients showed diffuse ground-glass opacity pattern. Seven of 10 patients had predisposing conditions such as unconsciousness, pharyngeal dysmotility, or motor disturbances, and 6 patients had a recent history of taking large amount of squalene through nasal route. Seven patients who had consolidation pattern had a history of taking squalene for several months and did not have any predisposing factor. All of the 5 patients who had a pattern of interstitial abnormalities had a history of taking squalene longer than 1 year and showed segmental distribution of interstitial thickening with interposing ground-glass opacities. Three patients simultaneously had two different patterns at different lobes of the lung. The HRCT findings of lipoid pneumonia are ground-glass opacities, consolidation, and interstitial abnormalities. These HRCT findings with appropriate inquiries could be useful for diagnosis of exogeneous lipoid pneumonia. (orig.)

  13. Quantitative analysis of cholesteatoma using high resolution computed tomography

    International Nuclear Information System (INIS)

    Kikuchi, Shigeru; Yamasoba, Tatsuya; Iinuma, Toshitaka.

    1992-01-01

    Seventy-three cases of adult cholesteatoma, including 52 cases of pars flaccida type cholesteatoma and 21 of pars tensa type cholesteatoma, were examined using high resolution computed tomography, in both axial (lateral semicircular canal plane) and coronal sections (cochlear, vestibular and antral plane). These cases were classified into two subtypes according to the presence of extension of cholesteatoma into the antrum. Sixty cases of chronic otitis media with central perforation (COM) were also examined as controls. Various locations of the middle ear cavity were measured in terms of size in comparison with pars flaccida type cholesteatoma, pars tensa type cholesteatoma and COM. The width of the attic was significantly larger in both pars flaccida type and pars tensa type cholesteatoma than in COM. With pars flaccida type cholesteatoma there was a significantly larger distance between the malleus and lateral wall of the attic than with COM. In contrast, the distance between the malleus and medial wall of the attic was significantly larger with pars tensa type cholesteatoma than with COM. With cholesteatoma extending into the antrum, regardless of the type of cholesteatoma, there were significantly larger distances than with COM at the following sites: the width and height of the aditus ad antrum, and the width, height and anterior-posterior diameter of the antrum. However, these distances were not significantly different between cholesteatoma without extension into the antrum and COM. The hitherto demonstrated qualitative impressions of bone destruction in cholesteatoma were quantitatively verified in detail using high resolution computed tomography. (author)

  14. Characterization of ceramic archaeological by high resolution X ray microtomography

    International Nuclear Information System (INIS)

    Machado, Alessandra C.; Freitas, Renato; Calza, Cristiane F.; Lopes, Ricardo T.; Lima, Inaya; Carvalho, Daniele D.; Gaspar, Maria D.

    2013-01-01

    Characterization of ceramic fragments is a very important area of research in art and archeometry area because it enables a greater understanding of how ancient civilizations behave and what were their traditions and customs. Petrography and chemical analyses are commonly used, but these techniques are destructive, which is not interesting for this type of sample. Through the exchange of multidisciplinary scientific knowledge and new partnerships, high resolution X-ray microtomography has been introduced in archaeological area as a great possibility of 3D inspection in a non-destructive way. The goal of this work is to investigate the internal microstructures of four samples of archeological ceramic, from the Archaeological Site of Macacu - RJ. The X-ray microtomography were performed in a high resolution setup, and can be used to infer the nature of organic temper even with all plant remains completely burnt out during the firing process and also to ensure the homogeneity of samples envisaged for geochemical analyses, especially with respect to the distribution of chemically diverse fabric compounds. In this way this study intends to contribute to our understanding of the archaeological and historical formations of this region. (author)

  15. Characterization of ceramic archaeological by high resolution X ray microtomography

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Alessandra C.; Freitas, Renato; Calza, Cristiane F.; Lopes, Ricardo T.; Lima, Inaya, E-mail: alecastro@lin.ufrj.br [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Lab. de Instrumentacao Nuclear; Carvalho, Daniele D.; Gaspar, Maria D. [Museu Nacional (MN/UFRJ), RJ (Brazil). Centro de Tecnologia

    2013-07-01

    Characterization of ceramic fragments is a very important area of research in art and archeometry area because it enables a greater understanding of how ancient civilizations behave and what were their traditions and customs. Petrography and chemical analyses are commonly used, but these techniques are destructive, which is not interesting for this type of sample. Through the exchange of multidisciplinary scientific knowledge and new partnerships, high resolution X-ray microtomography has been introduced in archaeological area as a great possibility of 3D inspection in a non-destructive way. The goal of this work is to investigate the internal microstructures of four samples of archeological ceramic, from the Archaeological Site of Macacu - RJ. The X-ray microtomography were performed in a high resolution setup, and can be used to infer the nature of organic temper even with all plant remains completely burnt out during the firing process and also to ensure the homogeneity of samples envisaged for geochemical analyses, especially with respect to the distribution of chemically diverse fabric compounds. In this way this study intends to contribute to our understanding of the archaeological and historical formations of this region. (author)

  16. MR-Venography Using High Resolution True-FISP

    Energy Technology Data Exchange (ETDEWEB)

    Spuentrup, E. [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik; Beth Israel Deaconess Medical Center, Boston, MA (United States). Dept. of Medicine; Harvard Medical School, Boston, MA (United States); Buecker, A.; Guenther, R.W. [Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik; Stuber, M. [Beth Israel Deaconess Medical Center, Boston, MA (United States). Dept. of Medicine; Harvard Medical School, Boston, MA (United States); Philips Med. Syst., Best (Netherlands)

    2001-08-01

    A new fast MR-venography approach using a high resolution True-FISP imaging sequence was investigated in 20 patients suffering from 23 deep vein thromboses. Diagnosis was proven by X-ray venography, CT or ultrasound examination. The presented technique allowed for clear thrombus visualization with a high contrast to the surrounding blood pool even in calf veins. Acquisition time was less than 10 minutes for imaging the pelvis and the legs. No contrast media was needed. The presented high resolution True-FISP MR-veography is a promising non-invasive, fast MR-venography approach for detection of deep venous thrombosis. (orig.) [German] Eine neue schnelle, oertlich hochaufgeloeste MR-Phlebographietechnik mit einer axialen True-FISP Bildgebungssequenz wurde an 20 Patienten mit 23 nach-gewiesenen tiefen Beinvenenthrombosen untersucht. Die Befunde wurden mit einer konventionellen Roentgenphlebographie, einer CT oder einer Sonographie gesichert. Die vorgestellte Technik erlaubte in allen Faellen eine Thrombusdarstellung mit hohem Kontrast zum umgebenden venoesen Blut, wobei aufgrund der hohen Ortsaufloesung auch die Unterschenkelvenen beurteilt werden konnten. Die Datenaufnahmezeit zur Untersuchung des Beckens und der Beine betrug weniger als 10 Minuten. Kontrastmittel wurde nicht benoetigt. Die vorgestellte MR-Phlebographietechnik unter Verwendung einer oertlich hochauf-geloesten True-FISP Sequenz ist eine neue, vielversprechende, nicht-invasive Technik zur Diagnostik der tiefen Bein- und Beckenvenenthrombose. (orig.)

  17. High-resolution electron microscopy of advanced materials

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, T.E.; Kung, H.H.; Sickafus, K.E.; Gray, G.T. III; Field, R.D.; Smith, J.F. [Los Alamos National Lab., NM (United States). Materials Science and Technology Div.

    1997-11-01

    This final report chronicles a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The High-Resolution Electron Microscopy Facility has doubled in size and tripled in quality since the beginning of the three-year period. The facility now includes a field-emission scanning electron microscope, a 100 kV field-emission scanning transmission electron microscope (FE-STEM), a 300 kV field-emission high-resolution transmission electron microscope (FE-HRTEM), and a 300 kV analytical transmission electron microscope. A new orientation imaging microscope is being installed. X-ray energy dispersive spectrometers for chemical analysis are available on all four microscopes; parallel electron energy loss spectrometers are operational on the FE-STEM and FE-HRTEM. These systems enable evaluation of local atomic bonding, as well as chemical composition in nanometer-scale regions. The FE-HRTEM has a point-to-point resolution of 1.6 {angstrom}, but the resolution can be pushed to its information limit of 1 {angstrom} by computer reconstruction of a focal series of images. HRTEM has been used to image the atomic structure of defects such as dislocations, grain boundaries, and interfaces in a variety of materials from superconductors and ferroelectrics to structural ceramics and intermetallics.

  18. Pulmonary leukemic involvement: high-resolution computed tomography evaluation

    International Nuclear Information System (INIS)

    Oliveira, Ana Paola de; Marchiori, Edson; Souza Junior, Arthur Soares

    2004-01-01

    Objective: To evaluate the role of high-resolution computed tomography (HRCT) in patients with leukemia and pulmonary symptoms, to establish the main patterns and to correlate them with the etiology. Materials and Methods: This is a retrospective study of the HRCT of 15 patients with leukemia and pulmonary symptoms. The examinations were performed using a spatial high-resolution protocol and were analyzed by two independent radiologists. Results: The main HRCT patterns found were ground-glass opacity (n=11), consolidation (n=9), airspace nodules (n=3), septal thickening (n=3), tree-in-bud pattern (n=3), and pleural effusion (n=3). Pulmonary infection was the most common finding seen in 12 patients: bacterial pneumonia (n=6), fungal infection (n = 4), pulmonary tuberculosis (n=1) and viral infection (n=1). Leukemic pleural infiltration (n=1), lymphoma (n=1) and pulmonary hemorrhage (n=1) were detected in the other three patients. Conclusion: HRCT is an important tool that may suggest the cause of lung involvement, its extension and in some cases to guide invasive procedures in patients with leukemia. (author)

  19. Peculiar velocity effects in high-resolution microwave background experiments

    International Nuclear Information System (INIS)

    Challinor, Anthony; Leeuwen, Floor van

    2002-01-01

    We investigate the impact of peculiar velocity effects due to the motion of the solar system relative to the cosmic microwave background (CMB) on high resolution CMB experiments. It is well known that on the largest angular scales the combined effects of Doppler shifts and aberration are important; the lowest Legendre multipoles of total intensity receive power from the large CMB monopole in transforming from the CMB frame. On small angular scales aberration dominates and is shown here to lead to significant distortions of the total intensity and polarization multipoles in transforming from the rest frame of the CMB to the frame of the solar system. We provide convenient analytic results for the distortions as series expansions in the relative velocity of the two frames, but at the highest resolutions a numerical quadrature is required. Although many of the high resolution multipoles themselves are severely distorted by the frame transformations, we show that their statistical properties distort by only an insignificant amount. Therefore, the cosmological parameter estimation is insensitive to the transformation from the CMB frame (where theoretical predictions are calculated) to the rest frame of the experiment

  20. Image thresholding in the high resolution target movement monitor

    Science.gov (United States)

    Moss, Randy H.; Watkins, Steve E.; Jones, Tristan H.; Apel, Derek B.; Bairineni, Deepti

    2009-03-01

    Image thresholding in the High Resolution Target Movement Monitor (HRTMM) is examined. The HRTMM was developed at the Missouri University of Science and Technology to detect and measure wall movements in underground mines to help reduce fatality and injury rates. The system detects the movement of a target with sub-millimeter accuracy based on the images of one or more laser dots projected on the target and viewed by a high-resolution camera. The relative position of the centroid of the laser dot (determined by software using thresholding concepts) in the images is the key factor in detecting the target movement. Prior versions of the HRTMM set the image threshold based on a manual, visual examination of the images. This work systematically examines the effect of varying threshold on the calculated centroid position and describes an algorithm for determining a threshold setting. First, the thresholding effects on the centroid position are determined for a stationary target. Plots of the centroid positions as a function of varying thresholds are obtained to identify clusters of thresholds for which the centroid position does not change for stationary targets. Second, the target is moved away from the camera in sub-millimeter increments and several images are obtained at each position and analyzed as a function of centroid position, target movement and varying threshold values. With this approach, the HRTMM can accommodate images in batch mode without the need for manual intervention. The capability for the HRTMM to provide automated, continuous monitoring of wall movement is enhanced.

  1. A high resolution pneumatic stepping actuator for harsh reactor environments

    Science.gov (United States)

    Tippetts, Thomas B.; Evans, Paul S.; Riffle, George K.

    1993-01-01

    A reactivity control actuator for a high-power density nuclear propulsion reactor must be installed in close proximity to the reactor core. The energy input from radiation to the actuator structure could exceed hundreds of W/cc unless low-cross section, low-absorptivity materials are chosen. Also, for post-test handling and subsequent storage, materials should not be used that are activated into long half-life isotopes. Pneumatic actuators can be constructed from various reactor-compatible materials, but conventional pneumatic piston actuators generally lack the stiffness required for high resolution reactivity control unless electrical position sensors and compensated electronic control systems are used. To overcome these limitations, a pneumatic actuator is under development that positions an output shaft in response to a series of pneumatic pulses, comprising a pneumatic analog of an electrical stepping motor. The pneumatic pulses are generated remotely, beyond the strong radiation environment, and transmitted to the actuator through tubing. The mechanically simple actuator uses a nutating gear harmonic drive to convert motion of small pistons directly to high-resolution angular motion of the output shaft. The digital nature of this actuator is suitable for various reactor control algorithms but is especially compatible with the three bean salad algorithm discussed by Ball et al. (1991).

  2. Evaluation of a high resolution silicon PET insert module

    Energy Technology Data Exchange (ETDEWEB)

    Grkovski, Milan, E-mail: milan.grkovski@ijs.si [Jožef Stefan Institute, Ljubljana (Slovenia); Memorial Sloan Kettering Cancer Center, New York, NY (United States); Brzezinski, Karol [IFIC/CSIC, Valencia (Spain); Cindro, Vladimir [Jožef Stefan Institute, Ljubljana (Slovenia); Clinthorne, Neal H. [University of Michigan, Ann Arbor, MI (United States); Kagan, Harris [Ohio State University, Columbus, OH (United States); Lacasta, Carlos [IFIC/CSIC, Valencia (Spain); Mikuž, Marko [Jožef Stefan Institute, Ljubljana (Slovenia); Solaz, Carles [IFIC/CSIC, Valencia (Spain); Studen, Andrej [Jožef Stefan Institute, Ljubljana (Slovenia); Weilhammer, Peter [Ohio State University, Columbus, OH (United States); Žontar, Dejan [Jožef Stefan Institute, Ljubljana (Slovenia)

    2015-07-11

    Conventional PET systems can be augmented with additional detectors placed in close proximity of the region of interest. We developed a high resolution PET insert module to evaluate the added benefit of such a combination. The insert module consists of two back-to-back 1 mm thick silicon sensors, each segmented into 1040 1 mm{sup 2} pads arranged in a 40 by 26 array. A set of 16 VATAGP7.1 ASICs and a custom assembled data acquisition board were used to read out the signal from the insert module. Data were acquired in slice (2D) geometry with a Jaszczak phantom (rod diameters of 1.2–4.8 mm) filled with {sup 18}F-FDG and the images were reconstructed with ML-EM method. Both data with full and limited angular coverage from the insert module were considered and three types of coincidence events were combined. The ratio of high-resolution data that substantially improves quality of the reconstructed image for the region near the surface of the insert module was estimated to be about 4%. Results from our previous studies suggest that such ratio could be achieved at a moderate technological expense by using an equivalent of two insert modules (an effective sensor thickness of 4 mm)

  3. The development of high resolution silicon x-ray microcalorimeters

    Science.gov (United States)

    Porter, F. S.; Kelley, R. L.; Kilbourne, C. A.

    2005-12-01

    Recently we have produced x-ray microcalorimeters with resolving powers approaching 2000 at 5.9 keV using a spare XRS microcalorimeter array. We attached 400 um square, 8 um thick HgTe absorbers using a variety of attachment methods to an XRS array and ran the detector array at temperatures between 40 and 60 mK. The best results were for absorbers attached using the standard XRS absorber-pixel thermal isolation scheme utilizing SU8 polymer tubes. In this scenario we achieved a resolution of 3.2 eV FWHM at 5.9 keV. Substituting a silicon spacer for the SU8 tubes also yielded sub-4eV results. In contrast, absorbers attached directly to the thermistor produced significant position dependence and thus degraded resolution. Finally, we tested standard 640um-square XRS detectors at reduced bias power at 50mK and achieved a resolution of 3.7eV, a 50% improvement over the XRS flight instrument. Implanted silicon microcalorimeters are a mature flight-qualified technology that still has a substantial phase space for future development. We will discuss these new high resolution results, the various absorber attachment schemes, planned future improvements, and, finally, their relevance to future high resolution x-ray spectrometers including Constellation-X.

  4. High resolution muon computed tomography at neutrino beam facilities

    International Nuclear Information System (INIS)

    Suerfu, B.; Tully, C.G.

    2016-01-01

    X-ray computed tomography (CT) has an indispensable role in constructing 3D images of objects made from light materials. However, limited by absorption coefficients, X-rays cannot deeply penetrate materials such as copper and lead. Here we show via simulation that muon beams can provide high resolution tomographic images of dense objects and of structures within the interior of dense objects. The effects of resolution broadening from multiple scattering diminish with increasing muon momentum. As the momentum of the muon increases, the contrast of the image goes down and therefore requires higher resolution in the muon spectrometer to resolve the image. The variance of the measured muon momentum reaches a minimum and then increases with increasing muon momentum. The impact of the increase in variance is to require a higher integrated muon flux to reduce fluctuations. The flux requirements and level of contrast needed for high resolution muon computed tomography are well matched to the muons produced in the pion decay pipe at a neutrino beam facility and what can be achieved for momentum resolution in a muon spectrometer. Such an imaging system can be applied in archaeology, art history, engineering, material identification and whenever there is a need to image inside a transportable object constructed of dense materials

  5. An original acquisition chain for the TOHR High Resolution Tomograph

    International Nuclear Information System (INIS)

    Pinot, Laurent

    1999-01-01

    The framework of this work is part of a new approach of emission tomography adapted to small animals. The principle of our tomographic system TOHR (French acronym for High Resolution Tomograph) is based on the use of large solid angle and high resolution focusing collimators each mounted in front of a detection module of high efficiency. With a first-generation acquisition chain we were able to characterize TOHR, however, to take fully advantage of the TOHR possibilities, a completely new acquisition scheme had to be designed. This system, being the main topic of this work, makes use of temporal information. The detection of a particle that entered the detector is translated into temporal logical signals. These signals pass into a time coding circuitry and the coded results are transferred in a digital processor. According to the initial terms of delivery, the developed acquisition chain steers the detection of events dependent on the deposited energy and time of arrival. The latter is done by coincidence measurements. All elements are mounted on a special board included into a PC unit and a dedicated program controls the whole system. First experiments showed up the interest of the new acquisition unit for other application in physics or medical imaging

  6. High resolution and simultaneous monitoring of airborne radionuclides

    International Nuclear Information System (INIS)

    Abe, T.; Yamaguchi, Y.; Muguntha Manikandan, N.; Komura, K.

    2005-01-01

    By using 11 extremely low background Ge detectors at Ogoya Underground Laboratory, it became possible to investigate temporal variations of airborne 212 Pb (T 1/2 =10.6 h) along with 210 Pb and 7 Be with order of magnitude higher time resolution. Then, we have measured airborne nuclides at three monitoring points, (1) roof of our laboratory (LLRL; 40 m ASL), (2) Shinshiku Plateau (640 m ASL) located about 8 km from LLRL as a comparison of vertical distribution, and (3) Hegura Island (10 m ASL) at about 50 km from Wajima located north of Noto Peninsula facing on the Sea of Japan (about 180 km to the north-northeast of LLRL), to investigate influence of Asian continent. Airborne nuclides were collected by high volume air samplers at intervals of a few hours at either two or three points simultaneously. In the same manner, high resolution monitoring was carried out also at the time of passage of typhoon and cold front. In this study, we observed drastic temporal variations of airborne radionuclides and correlations of multiple monitoring points. The results indicate that high resolution and simultaneous monitoring is very useful to understand dynamic state of variations of airborne nuclides due to short and long-term air-mass movement. (author)

  7. High-Resolution Electronics: Spontaneous Patterning of High-Resolution Electronics via Parallel Vacuum Ultraviolet (Adv. Mater. 31/2016).

    Science.gov (United States)

    Liu, Xuying; Kanehara, Masayuki; Liu, Chuan; Sakamoto, Kenji; Yasuda, Takeshi; Takeya, Jun; Minari, Takeo

    2016-08-01

    On page 6568, T. Minari and co-workers describe spontaneous patterning based on the parallel vacuum ultraviolet (PVUV) technique, enabling the homogeneous integration of complex, high-resolution electronic circuits, even on large-scale, flexible, transparent substrates. Irradiation of PVUV to the hydrophobic polymer surface precisely renders the selected surface into highly wettable regions with sharply defined boundaries, which spontaneously guides a metal nanoparticle ink into a series of circuit lines and gaps with the widths down to a resolution of 1 μm. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Toward explaining the Holocene carbon dioxide and carbon isotope records: Results from transient ocean carbon cycle-climate simulations

    Science.gov (United States)

    Menviel, L.; Joos, F.

    2012-03-01

    The Bern3D model was applied to quantify the mechanisms of carbon cycle changes during the Holocene (last 11,000 years). We rely on scenarios from the literature to prescribe the evolution of shallow water carbonate deposition and of land carbon inventory changes over the glacial termination (18,000 to 11,000 years ago) and the Holocene and modify these scenarios within uncertainties. Model results are consistent with Holocene records of atmospheric CO2 and δ13C as well as the spatiotemporal evolution of δ13C and carbonate ion concentration in the deep sea. Deposition of shallow water carbonate, carbonate compensation of land uptake during the glacial termination, land carbon uptake and release during the Holocene, and the response of the ocean-sediment system to marine changes during the termination contribute roughly equally to the reconstructed late Holocene pCO2 rise of 20 ppmv. The 5 ppmv early Holocene pCO2 decrease reflects terrestrial uptake largely compensated by carbonate deposition and ocean sediment responses. Additional small contributions arise from Holocene changes in sea surface temperature, ocean circulation, and export productivity. The Holocene pCO2 variations result from the subtle balance of forcings and processes acting on different timescales and partly in opposite direction as well as from memory effects associated with changes occurring during the termination. Different interglacial periods with different forcing histories are thus expected to yield different pCO2 evolutions as documented by ice cores.

  9. Temporal dynamics of motivation-cognitive control interactions revealed by high-resolution pupillometry

    Directory of Open Access Journals (Sweden)

    Kimberly Sarah Chiew

    2013-01-01

    Full Text Available Motivational manipulations, such as the presence of performance-contingent reward incentives, can have substantial influences on cognitive control. Previous evidence suggests that reward incentives may enhance cognitive performance specifically through increased preparatory, or proactive, control processes. The present study examined reward influences on cognitive control dynamics in the AX-Continuous Performance Task (AX-CPT, using high-resolution pupillometry. In the AX-CPT, contextual cues must be actively maintained over a delay in order to appropriately respond to ambiguous target probes. A key feature of the task is that it permits dissociable characterization of preparatory, proactive control processes (i.e., utilization of context and reactive control processes (i.e., target-evoked interference resolution. Task performance profiles suggested that reward incentives enhanced proactive control (context utilization. Critically, pupil dilation was also increased on reward incentive trials during context maintenance periods, suggesting trial-specific shifts in proactive control, particularly when context cues indicated the need to overcome the dominant target response bias. Reward incentives had both transient (i.e., trial-by-trial and sustained (i.e., block-based effects on pupil dilation, which may reflect distinct underlying processes. The transient pupillary effects were present even when comparing against trials matched in task performance, suggesting a unique motivational influence of reward incentives. These results suggest that pupillometry may be a useful technique for investigating reward motivational signals and their dynamic influence on cognitive control.

  10. High resolution modelling of extreme precipitation events in urban areas

    Science.gov (United States)

    Siemerink, Martijn; Volp, Nicolette; Schuurmans, Wytze; Deckers, Dave

    2015-04-01

    The present day society needs to adjust to the effects of climate change. More extreme weather conditions are expected, which can lead to longer periods of drought, but also to more extreme precipitation events. Urban water systems are not designed for such extreme events. Most sewer systems are not able to drain the excessive storm water, causing urban flooding. This leads to high economic damage. In order to take appropriate measures against extreme urban storms, detailed knowledge about the behaviour of the urban water system above and below the streets is required. To investigate the behaviour of urban water systems during extreme precipitation events new assessment tools are necessary. These tools should provide a detailed and integral description of the flow in the full domain of overland runoff, sewer flow, surface water flow and groundwater flow. We developed a new assessment tool, called 3Di, which provides detailed insight in the urban water system. This tool is based on a new numerical methodology that can accurately deal with the interaction between overland runoff, sewer flow and surface water flow. A one-dimensional model for the sewer system and open channel flow is fully coupled to a two-dimensional depth-averaged model that simulates the overland flow. The tool uses a subgrid-based approach in order to take high resolution information of the sewer system and of the terrain into account [1, 2]. The combination of using the high resolution information and the subgrid based approach results in an accurate and efficient modelling tool. It is now possible to simulate entire urban water systems using extreme high resolution (0.5m x 0.5m) terrain data in combination with a detailed sewer and surface water network representation. The new tool has been tested in several Dutch cities, such as Rotterdam, Amsterdam and The Hague. We will present the results of an extreme precipitation event in the city of Schiedam (The Netherlands). This city deals with

  11. High resolution remote sensing of water surface patterns

    Science.gov (United States)

    Woodget, A.; Visser, F.; Maddock, I.; Carbonneau, P.

    2012-12-01

    The assessment of in-stream habitat availability within fluvial environments in the UK traditionally includes the mapping of patterns which appear on the surface of the water, known as 'surface flow types' (SFTs). The UK's River Habitat Survey identifies ten key SFTs, including categories such as rippled flow, upwelling, broken standing waves and smooth flow. SFTs result from the interaction between the underlying channel morphology, water depth and velocity and reflect the local flow hydraulics. It has been shown that SFTs can be both biologically and hydraulically distinct. SFT mapping is usually conducted from the river banks where estimates of spatial coverage are made by eye. This approach is affected by user subjectivity and inaccuracies in the spatial extent of mapped units. Remote sensing and specifically the recent developments in unmanned aerial systems (UAS) may now offer an alternative approach for SFT mapping, with the capability for rapid and repeatable collection of very high resolution imagery from low altitudes, under bespoke flight conditions. This PhD research is aimed at investigating the mapping of SFTs using high resolution optical imagery (less than 10cm) collected from a helicopter-based UAS flown at low altitudes (less than 100m). This paper presents the initial findings from a series of structured experiments on the River Arrow, a small lowland river in Warwickshire, UK. These experiments investigate the potential for mapping SFTs from still and video imagery of different spatial resolutions collected at different flying altitudes and from different viewing angles (i.e. vertical and oblique). Imagery is processed using 3D mosaicking software to create orthophotos and digital elevation models (DEM). The types of image analysis which are tested include a simple, manual visual assessment undertaken in a GIS environment, based on the high resolution optical imagery. In addition, an object-based image analysis approach which makes use of the

  12. A PICTORIAL PRESENTATION OF ESOPHAGEAL HIGH RESOLUTION MANOMETRY CURRENT PARAMETERS.

    Science.gov (United States)

    Lafraia, Fernanda M; Herbella, Fernando A M; Kalluf, Julia R; Patti, Marco G

    2017-01-01

    High resolution manometry is the current technology used to the study of esophageal motility and is replacing conventional manometry in important centers for esophageal motility with parameters used on esophageal motility, following the Chicago Classification. This classification unifies high resolution manometry interpretation and classifies esophageal disorders. This review shows, in a pictorial presentation, the new parameters established by the Chicago Classification, version 3.0, aimed to allow an easy comprehension and interpretation of high resolution manometry. Esophageal manometries performed by the authors were reviewed to select illustrative tracings representing Chicago Classification parameters. The parameters are: Esophagogastric Morphology, that classifies this junction according to its physiology and anatomy; Integrated Relaxation Pressure, that measures the lower esophageal sphincter relaxation; Distal Contractile Integral, that evaluates the contraction vigor of each wave; and, Distal Latency, that measures the peristalsis velocity from the beginning of the swallow to the epiphrenic ampulla. Clinical applications of these new concepts is still under evaluation. Mostrar, de forma pictórica, os novos parâmetros compilados na versão 3.0 da Classificação de Chicago, buscando facilitar a compreensão e interpretação da manometria de alta resolução. Foram revistas as manometrias da casuística dos autores e selecionados os traçados representativos dos parâmetros da Classificação de Chicago. Entre os parâmetros apresentados foram considerados a Morfologia da Transição Gastroesofágica, que classifica o segmento de acordo com sua fisiologia e anatomia; a Integral da Pressão de Relaxamento, que mede o relaxamento do esfíncter esofagiano inferior; a Integral Contrátil Distal, que avalia o vigor contrátil da onda peristáltica; e, a Latência Distal, que mede o tempo da peristalse, desde o início da deglutição até a ampola epifr

  13. Application of ultra-fast high-resolution gated-image intensifiers to laser fusion studies

    International Nuclear Information System (INIS)

    Lieber, A.J.; Benjamin, R.F.; Sutphin, H.D.; McCall, G.H.

    1975-01-01

    Gated-image intensifiers for fast framing have found high utility in laser-target interaction studies. X-ray pinhole camera photographs which can record asymmetries of laser-target interactions have been instrumental in further system design. High-resolution high-speed x-ray images of laser irradiated targets are formed using pinhole optics and electronically amplified by proximity focused channelplate intensifiers before being recorded on film. Spectral resolution is obtained by filtering. In these applications shutter duration is determined by source duration. Electronic gating serves to reduce background thereby enhancing signal-to-noise ratio. Cameras are used to view the self light of the interaction but may also be used for shadowgraphs. Sources for shadowgraphs may be sequenced to obtain a series of pictures with effective rates of 10 10 frame/s. Multiple aperatures have been used to obtain stereo x-ray views, yielding three dimensional information about the interactions. (author)

  14. Multi-dimensional analysis of high resolution {gamma}-ray data

    Energy Technology Data Exchange (ETDEWEB)

    Flibotte, S.; Huettmeier, U.J.; France, G. de; Haas, B.; Romain, P.; Theisen, Ch.; Vivien, J.P.; Zen, J. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires

    1992-12-31

    A new generation of high resolution {gamma}-ray spectrometers capable of recording high-fold coincidence events with a large efficiency will soon be available. Algorithms are developed to analyze high-fold {gamma}-ray coincidences. As a contribution to the software development associated with the EUROGAM spectrometer, the performances of computer codes designed to select multi-dimensional gates from 3-, 4- and 5-fold coincidence databases were tested. The tests were performed on events generated with a Monte Carlo simulation and also on real experimental triple data recorded with the 8{pi} spectrometer and with a preliminary version of the EUROGAM array. (R.P.) 14 refs.; 3 figs.; 3 tabs.

  15. Multi-dimensional analysis of high resolution γ-ray data

    International Nuclear Information System (INIS)

    Flibotte, S.; Huettmeier, U.J.; France, G. de; Haas, B.; Romain, P.; Theisen, Ch.; Vivien, J.P.; Zen, J.

    1992-01-01

    A new generation of high resolution γ-ray spectrometers capable of recording high-fold coincidence events with a large efficiency will soon be available. Algorithms are developed to analyze high-fold γ-ray coincidences. As a contribution to the software development associated with the EUROGAM spectrometer, the performances of computer codes designed to select multi-dimensional gates from 3-, 4- and 5-fold coincidence databases were tested. The tests were performed on events generated with a Monte Carlo simulation and also on real experimental triple data recorded with the 8π spectrometer and with a preliminary version of the EUROGAM array. (R.P.) 14 refs.; 3 figs.; 3 tabs

  16. A high-resolution Fourier Transform Spectrometer for planetary spectroscopy

    Science.gov (United States)

    Cruikshank, D. P.; Sinton, W. M.

    1973-01-01

    The employment of a high-resolution Fourier Transform Spectrometer (FTS) is described for planetary and other astronomical spectroscopy in conjunction with the 88-inch telescope at Mauna Kea Observatory. The FTS system is designed for a broad range of uses, including double-beam laboratory spectroscopy, infrared gas chromatography, and nuclear magnetic resonance spectroscopy. The data system is well-suited to astronomical applications because of its great speed in acquiring and transforming data, and because of the enormous storage capability of the magnetic tape unit supplied with the system. The basic instrument is outlined 2nd some of the initial results from the first attempted use on the Mauna Kea 88-inch telescope are reported.

  17. Unattented mode monitoring of high resolution gamma-ray spectra

    International Nuclear Information System (INIS)

    Smith, B.G.R.; Van Dyck, P.; Debraix, P.

    1991-01-01

    An Isotope Monitoring System (IMS) for unattended spectrum acquisition is described. This consists of a simple low cost flexible software package running on a Compaq 80386 and controlling up to 4 Canberra Packard System 100 multi-channel analyzer (MCA) cards. The IMS permits the independent configuration of each of the 4 MCA cards for different monitoring cycles and for different spectrum acquisition cycles each being based upon different trigger criteria. In this way IMS is able to automatically identify events, time tag them, and acquire and store valid spectra corresponding to those event. An additional feature of IMS permits to run a Multigroup Analysis (MGA) software package for the determination of plutonium isotopic compositions in batch mode. One particular application is discussed which consists of 4 high resolution gamma-ray detector systems connected together to the IMS for unattended spectrum acquisition. The off-line batch mode analysis of the spectra using MGA is also discussed

  18. High-resolution method for evolving complex interface networks

    Science.gov (United States)

    Pan, Shucheng; Hu, Xiangyu Y.; Adams, Nikolaus A.

    2018-04-01

    In this paper we describe a high-resolution transport formulation of the regional level-set approach for an improved prediction of the evolution of complex interface networks. The novelty of this method is twofold: (i) construction of local level sets and reconstruction of a global level set, (ii) local transport of the interface network by employing high-order spatial discretization schemes for improved representation of complex topologies. Various numerical test cases of multi-region flow problems, including triple-point advection, single vortex flow, mean curvature flow, normal driven flow, dry foam dynamics and shock-bubble interaction show that the method is accurate and suitable for a wide range of complex interface-network evolutions. Its overall computational cost is comparable to the Semi-Lagrangian regional level-set method while the prediction accuracy is significantly improved. The approach thus offers a viable alternative to previous interface-network level-set method.

  19. High resolution ultrasound and photoacoustic imaging of single cells

    Directory of Open Access Journals (Sweden)

    Eric M. Strohm

    2016-03-01

    Full Text Available High resolution ultrasound and photoacoustic images of stained neutrophils, lymphocytes and monocytes from a blood smear were acquired using a combined acoustic/photoacoustic microscope. Photoacoustic images were created using a pulsed 532 nm laser that was coupled to a single mode fiber to produce output wavelengths from 532 nm to 620 nm via stimulated Raman scattering. The excitation wavelength was selected using optical filters and focused onto the sample using a 20× objective. A 1000 MHz transducer was co-aligned with the laser spot and used for ultrasound and photoacoustic images, enabling micrometer resolution with both modalities. The different cell types could be easily identified due to variations in contrast within the acoustic and photoacoustic images. This technique provides a new way of probing leukocyte structure with potential applications towards detecting cellular abnormalities and diseased cells at the single cell level.

  20. HIGH-RESOLUTION ATMOSPHERIC ENSEMBLE MODELING AT SRNL

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, R.; Werth, D.; Chiswell, S.; Etherton, B.

    2011-05-10

    The High-Resolution Mid-Atlantic Forecasting Ensemble (HME) is a federated effort to improve operational forecasts related to precipitation, convection and boundary layer evolution, and fire weather utilizing data and computing resources from a diverse group of cooperating institutions in order to create a mesoscale ensemble from independent members. Collaborating organizations involved in the project include universities, National Weather Service offices, and national laboratories, including the Savannah River National Laboratory (SRNL). The ensemble system is produced from an overlapping numerical weather prediction model domain and parameter subsets provided by each contributing member. The coordination, synthesis, and dissemination of the ensemble information are performed by the Renaissance Computing Institute (RENCI) at the University of North Carolina-Chapel Hill. This paper discusses background related to the HME effort, SRNL participation, and example results available from the RENCI website.

  1. Precision Viticulture from Multitemporal, Multispectral Very High Resolution Satellite Data

    Science.gov (United States)

    Kandylakis, Z.; Karantzalos, K.

    2016-06-01

    In order to exploit efficiently very high resolution satellite multispectral data for precision agriculture applications, validated methodologies should be established which link the observed reflectance spectra with certain crop/plant/fruit biophysical and biochemical quality parameters. To this end, based on concurrent satellite and field campaigns during the veraison period, satellite and in-situ data were collected, along with several grape samples, at specific locations during the harvesting period. These data were collected for a period of three years in two viticultural areas in Northern Greece. After the required data pre-processing, canopy reflectance observations, through the combination of several vegetation indices were correlated with the quantitative results from the grape/must analysis of grape sampling. Results appear quite promising, indicating that certain key quality parameters (like brix levels, total phenolic content, brix to total acidity, anthocyanin levels) which describe the oenological potential, phenolic composition and chromatic characteristics can be efficiently estimated from the satellite data.

  2. High-Resolution Characterization of UMo Alloy Microstructure

    Energy Technology Data Exchange (ETDEWEB)

    Devaraj, Arun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kovarik, Libor [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Joshi, Vineet V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jana, Saumyadeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Manandhar, Sandeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Arey, Bruce W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lavender, Curt A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-11-30

    This report highlights the capabilities and procedure for high-resolution characterization of UMo fuels in PNNL. Uranium-molybdenum (UMo) fuel processing steps, from casting to forming final fuel, directly affect the microstructure of the fuel, which in turn dictates the in-reactor performance of the fuel under irradiation. In order to understand the influence of processing on UMo microstructure, microstructure characterization techniques are necessary. Higher-resolution characterization techniques like transmission electron microscopy (TEM) and atom probe tomography (APT) are needed to interrogate the details of the microstructure. The findings from TEM and APT are also directly beneficial for developing predictive multiscale modeling tools that can predict the microstructure as a function of process parameters. This report provides background on focused-ion-beam–based TEM and APT sample preparation, TEM and APT analysis procedures, and the unique information achievable through such advanced characterization capabilities for UMo fuels, from a fuel fabrication capability viewpoint.

  3. THE HIGH-RESOLUTION INFRARED SPECTRUM OF HCl{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Doménech, J. L.; Herrero, V. J.; Tanarro, I. [Molecular Physics Department, Instituto de Estructura de la Materia (IEM-CSIC), Serrano 123, E-28006 Madrid (Spain); Drouin, B. J. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099 (United States); Cernicharo, J., E-mail: jl.domenech@csic.es [Molecular Astrophysics Group, Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Sor Juana Inés de la Cruz 3, Cantoblanco, E-28049 Madrid (Spain)

    2016-12-20

    The chloroniumyl cation, HCl{sup +}, has been recently identified in space from Herschel 's spectra. A joint analysis of extensive vis-UV spectroscopy emission data together with a few high-resolution and high-accuracy millimeter-wave data provided the necessary rest frequencies to support the astronomical identification. Nevertheless, the analysis did not include any infrared (IR) vibration–rotation data. Furthermore, with the end of the Herschel mission, IR observations from the ground may be one of the few available means to further study this ion in space. In this work, we provide a set of accurate rovibrational transition wavenumbers, as well as a new and improved global fit of vis-UV, IR, and millimeter-wave spectroscopy laboratory data, that will aid in future studies of this molecule.

  4. Measuring large-scale social networks with high resolution.

    Directory of Open Access Journals (Sweden)

    Arkadiusz Stopczynski

    Full Text Available This paper describes the deployment of a large-scale study designed to measure human interactions across a variety of communication channels, with high temporal resolution and spanning multiple years-the Copenhagen Networks Study. Specifically, we collect data on face-to-face interactions, telecommunication, social networks, location, and background information (personality, demographics, health, politics for a densely connected population of 1000 individuals, using state-of-the-art smartphones as social sensors. Here we provide an overview of the related work and describe the motivation and research agenda driving the study. Additionally, the paper details the data-types measured, and the technical infrastructure in terms of both backend and phone software, as well as an outline of the deployment procedures. We document the participant privacy procedures and their underlying principles. The paper is concluded with early results from data analysis, illustrating the importance of multi-channel high-resolution approach to data collection.

  5. Application of the Oslo method to high resolution gamma spectra

    Science.gov (United States)

    Simon, A.; Guttormsen, M.; Larsen, A. C.; Beausang, C. W.; Humby, P.

    2015-10-01

    Hauser-Feshbach statistical model is a widely used tool for calculation of the reaction cross section, in particular for astrophysical processes. The HF model requires as an input an optical potential, gamma-strength function (GSF) and level density (LD) to properly model the statistical properties of the nucleus. The Oslo method is a well established technique to extract GSFs and LDs from experimental data, typically used for gamma-spectra obtained with scintillation detectors. Here, the first application of the Oslo method to high-resolution data obtained using the Ge detectors of the STARLITER setup at TAMU is discussed. The GSFs and LDs extracted from (p,d) and (p,t) reactions on 152154 ,Sm targets will be presented.

  6. Highly sensitive high resolution Raman spectroscopy using resonant ionization methods

    International Nuclear Information System (INIS)

    Owyoung, A.; Esherick, P.

    1984-05-01

    In recent years, the introduction of stimulated Raman methods has offered orders of magnitude improvement in spectral resolving power for gas phase Raman studies. Nevertheless, the inherent weakness of the Raman process suggests the need for significantly more sensitive techniques in Raman spectroscopy. In this we describe a new approach to this problem. Our new technique, which we call ionization-detected stimulated Raman spectroscopy (IDSRS), combines high-resolution SRS with highly-sensitive resonant laser ionization to achieve an increase in sensitivity of over three orders of magnitude. The excitation/detection process involves three sequential steps: (1) population of a vibrationally excited state via stimulated Raman pumping; (2) selective ionization of the vibrationally excited molecule with a tunable uv source; and (3) collection of the ionized species at biased electrodes where they are detected as current in an external circuit

  7. High resolution computed tomography of the middle ear

    International Nuclear Information System (INIS)

    Ikeda, Katsuhisa; Sakurai, Tokio; Saijo, Shigeru; Kobayashi, Toshimitsu

    1983-01-01

    High resolution computed tomography was performed in 57 cases with various middle ear diseases (chronic otitis media, otitis media with effusion, acute otitis media and atelectasis). Although further improvement in detectability is necessary in order to discriminate each type of the soft tissue lesions, CT is the most useful method currently available in detecting the small structures and soft tissue lesions of the middle ear. In particular, the lesions at the tympanic isthmus and tympanic fold could very clearly be detected only by CT. In acute otitis media, lesions usually started in the attic and spread to the mastoid air cells. In otitis media with effusion, the soft tissue shadow was ovserved in the attic and mastoid air cell. CT is valuable in diagnosis, evaluation of the treatment and prognosis, and analysis of pathophysiology in the middle ear diseases. (author)

  8. High resolution X-ray tomography for stationary multiphase flows

    International Nuclear Information System (INIS)

    Schmitz, D.; Reinecke, N.; Petritsch, G.; Mewes, D.

    1998-01-01

    The high resolution which can be obtained by computer assisted tomography is used to investigate the liquid distribution and void fraction in random and structured packing. With a spatial resolution of 0.4x0.4mm 2 it is possible even to detect thin liquid films on structured packings. The experimental set-up consists of a custom-built second generation tomograph. The imaged object consists of a column filled with either a random ceramic packing of spheres or a structured metal packing. The liquid and void fraction distribution in random and structured packings with a quiescent gaseous phase is visualized. The water/air system is used. The liquid distributor consists of a perforated plate. The experimental hold-up values averaged over the column cross-section are in good agreement with empirical equations. (author)

  9. Fast iterative segmentation of high resolution medical images

    International Nuclear Information System (INIS)

    Hebert, T.J.

    1996-01-01

    Various applications in positron emission tomography (PET), single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) require segmentation of 20 to 60 high resolution images of size 256x256 pixels in 3-9 seconds per image. This places particular constraints on the design of image segmentation algorithms. This paper examines the trade-offs in segmenting images based on fitting a density function to the pixel intensities using curve-fitting versus the maximum likelihood method. A quantized data representation is proposed and the EM algorithm for fitting a finite mixture density function to the quantized representation for an image is derived. A Monte Carlo evaluation of mean estimation error and classification error showed that the resulting quantized EM algorithm dramatically reduces the required computation time without loss of accuracy

  10. High resolution capacitance detection circuit for rotor micro-gyroscope

    Directory of Open Access Journals (Sweden)

    Ming-Yuan Ren

    2014-03-01

    Full Text Available Conventional methods for rotor position detection of micro-gyroscopes include common exciting electrodes (single frequency and common sensing electrodes (frequency multiplex, but they have encountered some problems. So we present a high resolution and low noise pick-off circuit for micro-gyroscopes which utilizes the time multiplex method. The detecting circuit adopts a continuous-time current sensing circuit for capacitance measurement, and its noise analysis of the charge amplifier is introduced. The equivalent output noise power spectral density of phase-sensitive demodulation is 120 nV/Hz1/2. Tests revealed that the whole circuitry has a relative capacitance resolution of 1 × 10−8.

  11. Automated high-resolution NMR with a sample changer

    International Nuclear Information System (INIS)

    Wade, C.G.; Johnson, R.D.; Philson, S.B.; Strouse, J.; McEnroe, F.J.

    1989-01-01

    Within the past two years, it has become possible to obtain high-resolution NMR spectra using automated commercial instrumentation. Software control of all spectrometer functions has reduced most of the tedious manual operations to typing a few computer commands or even making selections from a menu. Addition of an automatic sample changer is the next natural step in improving efficiency and sample throughput; it has a significant (and even unexpected) impact on how NMR laboratories are run and how it is taught. Such an instrument makes even sophisticated experiments routine, so that people with no previous exposure to NMR can run these experiments after a training session of an hour or less. This A/C Interface examines the impact of such instrumentation on both the academic and the industrial laboratory

  12. DETECTION OF BARCHAN DUNES IN HIGH RESOLUTION SATELLITE IMAGES

    Directory of Open Access Journals (Sweden)

    M. A. Azzaoui

    2016-06-01

    Full Text Available Barchan dunes are the fastest moving sand dunes in the desert. We developed a process to detect barchans dunes on High resolution satellite images. It consisted of three steps, we first enhanced the image using histogram equalization and noise reduction filters. Then, the second step proceeds to eliminate the parts of the image having a texture different from that of the barchans dunes. Using supervised learning, we tested a coarse to fine textural analysis based on Kolomogorov Smirnov test and Youden’s J-statistic on co-occurrence matrix. As an output we obtained a mask that we used in the next step to reduce the search area. In the third step we used a gliding window on the mask and check SURF features with SVM to get barchans dunes candidates. Detected barchans dunes were considered as the fusion of overlapping candidates. The results of this approach were very satisfying in processing time and precision.

  13. High resolution computed tomography of the post partum pituitary gland

    International Nuclear Information System (INIS)

    Hinshaw, D.B.; Hasso, A.N.; Thompson, J.R.; Davidson, B.J.

    1984-01-01

    Eight volunteer post partum female patients were examined with high resolution computed tomography during the week immediately after delivery. All patients received high dose (40-70 gm) intravenous iodine contrast administration. The scans were examined for pituitary gland height, shape and homogeneity. All of the patients had enlarged glands by the traditional standards (i.e. gland height of 8 mm or greater). The diaphragma sellae in every call bulged upward with a convex domed appearance. The glands were generally inhomogeneous. One gland had a 4 mm focal well defined area of decreased attenuation. Two patients who were studied again months later had glands which had returned to ''normal'' size. The enlarged, upwardly convex pituitary gland appears to be typical and normal for the recently post partum period. (orig.)

  14. High-resolution sonography in carpal tunnel syndrome

    International Nuclear Information System (INIS)

    Solbiati, L.; De Pra, L.; Rizzatto, G.; Derchi, L.E.

    1986-01-01

    Carpal tunnel syndrome, caused by the compression on the median nerve under the transverse carpal ligament, has multiple causes and clinical presentations. One hundred eighteen patients with carpal tunnel sydrome underwent high-resolution US which demonstrated unpalpable cystic masses in 25 patients (lobulated stalked synovial cysts in 19 and retrotendinous cysts in six, all confirmed at surgery), and diffuse thickening and decreased echogenicity of the tendon sheaths in 87 patients, suggesting tenosynovitis (confirmed at surgery in 64). In six patients simple encasement of muscle bellies in the carpal tunnel was shown. US can delineate the cause of carpal tunnel syndrome, suggest the need for surgery, and aid the surgeon in locating the lesion to be removed

  15. Feasibility tests of a high resolution sampling radial drift chamber

    International Nuclear Information System (INIS)

    Huth, J.

    1985-01-01

    The design concept and results of feasibility tests for a vertex detector intended for use in the TPC-PEP4/9 experiment are presented. The detector is based on a slow radial drift in dimethyl ether. High resolution localization of the avalanches at the sense wire is accomplished with nearby pickup wires and the utilization of waveform sampling electronics. The avalanche angular coordinate measurements, combined with knowledge of the electric field distribution and drift velocity permit reconstruction of the trajectory using essentially all track information. Measurements with a test chamber constructed to study characteristics of avalanche localization indicate that the recoverable track information in one centimeter of dimethyl ether at 1.5 atm is equivalent to 30 measurements of 40 μm accuracy. (orig.)

  16. Sparse Representation Denoising for Radar High Resolution Range Profiling

    Directory of Open Access Journals (Sweden)

    Min Li

    2014-01-01

    Full Text Available Radar high resolution range profile has attracted considerable attention in radar automatic target recognition. In practice, radar return is usually contaminated by noise, which results in profile distortion and recognition performance degradation. To deal with this problem, in this paper, a novel denoising method based on sparse representation is proposed to remove the Gaussian white additive noise. The return is sparsely described in the Fourier redundant dictionary and the denoising problem is described as a sparse representation model. Noise level of the return, which is crucial to the denoising performance but often unknown, is estimated by performing subspace method on the sliding subsequence correlation matrix. Sliding window process enables noise level estimation using only one observation sequence, not only guaranteeing estimation efficiency but also avoiding the influence of profile time-shift sensitivity. Experimental results show that the proposed method can effectively improve the signal-to-noise ratio of the return, leading to a high-quality profile.

  17. Neutron spin echo and high resolution inelastic spectroscopy

    International Nuclear Information System (INIS)

    Mezei, F.; Hungarian Academy of Sciences, Budapest. Central Research Inst. for Physics)

    1982-01-01

    The principles of neutrons spin echo (NSE) technique are considered. It is shown that the basis of NSE principle is a single step measurement of the change of the neutron velocity in the scattering process. The backscattering soectroscopy and the NSE techniques are compared. The NSF spectrometer is described. It is shown that 0.5 MeV energy resolution achieved in the NSE experiment is about 40 times superior to those achieved by the other techniques. The NSE technique has the unique feature that provides high resolution in neutron energy change independently of the monochromatization of the beam. The NSE instrument not only covers a wider dynamic range on a pulsed source that on a continuous one, but also collects data more efficiently

  18. High-resolution electron microscopy and its applications.

    Science.gov (United States)

    Li, F H

    1987-12-01

    A review of research on high-resolution electron microscopy (HREM) carried out at the Institute of Physics, the Chinese Academy of Sciences, is presented. Apart from the direct observation of crystal and quasicrystal defects for some alloys, oxides, minerals, etc., and the structure determination for some minute crystals, an approximate image-contrast theory named pseudo-weak-phase object approximation (PWPOA), which shows the image contrast change with crystal thickness, is described. Within the framework of PWPOA, the image contrast of lithium ions in the crystal of R-Li2Ti3O7 has been observed. The usefulness of diffraction analysis techniques such as the direct method and Patterson method in HREM is discussed. Image deconvolution and resolution enhancement for weak-phase objects by use of the direct method are illustrated. In addition, preliminary results of image restoration for thick crystals are given.

  19. High resolution CT in children with cystic fibrosis

    International Nuclear Information System (INIS)

    Stiglbauer, R.; Schurawitzki, H.; Eichler, I.; Goetz, M.

    1992-01-01

    High resolution CT (HRCT) was performed in 24 children (median age 57.9 months) suffering from cystic fibrosis (CF). In 23 patients (one examination unacceptable because of motion artifacts) the most frequent finding was bronchial wall thickening, shown in 21 patients (91%), followed by bronchiectasis in 15 patients (65%). Less frequent findings were mucus plugging and patchy consolidations, which could be demonstrated in 11 patients each (48%). Findings were classified using a CT scoring system and including only irreversible pulmonary changes; a statistically significant correlation with lung function tests could be established. HRCT to date seems to be the most valuable method to determine extent and severity of lung involvement in children with CF and should therefore be routinely used for the staging of this disease. (orig.)

  20. Porous silicon phantoms for high-resolution scintillation imaging

    Energy Technology Data Exchange (ETDEWEB)

    Di Francia, G. [Portici Research Centre, ENEA, Via Vecchio Macello, 80055 Portici, Naples (Italy); Scafe, R. [Casaccia Research Centre, ENEA, 00060 S.Maria di Galeria, Rome (Italy)]. E-mail: scafe@casaccia.enea.it; De Vincentis, G. [Department of Radiological Sciences, University of Rome ' La Sapienza' , V.le Regina Elena, 324, 00161 Rome (Italy); La Ferrara, V. [Portici Research Centre, ENEA, Via Vecchio Macello, 80055 Portici, Naples (Italy); Iurlaro, G. [Casaccia Research Centre, ENEA, 00060 S.Maria di Galeria, Rome (Italy); Nasti, I. [Portici Research Centre, ENEA, Via Vecchio Macello, 80055 Portici, Naples (Italy); Montani, L. [Casaccia Research Centre, ENEA, 00060 S.Maria di Galeria, Rome (Italy); Pellegrini, R. [Department of Experimental Medicine, University of Rome ' La Sapienza' , V.le Regina Elena, 324, 00161 Rome (Italy); Betti, M. [Department of Experimental Medicine, University of Rome ' La Sapienza' , V.le Regina Elena, 324, 00161 Rome (Italy); Martucciello, N. [Portici Research Centre, ENEA, Via Vecchio Macello, 80055 Portici, Naples (Italy); Pani, R. [Department of Experimental Medicine, University of Rome ' La Sapienza' , V.le Regina Elena, 324, 00161 Rome (Italy)

    2006-12-20

    High resolution radionuclide imaging requires phantoms with precise geometries and known activities using either Anger cameras equipped with pinhole collimators or dedicated small animal devices. Porous silicon samples, having areas of different shape and size, can be made and loaded with a radioactive material, obtaining: (a) precise radio-emitting figures corresponding to the porous areas geometry (b) a radioactivity of each figure depending on the pore's specifications, and (c) the same emission energy to be used in true exams. To this aim a sample with porous circular areas has been made and loaded with a {sup 99m}TcO{sub 4} {sup -} solution. Imaging has been obtained using both general purpose and pinhole collimators. This first sample shows some defects that are analyzed and discussed.

  1. High-resolution 3-T MR neurography of peroneal neuropathy

    International Nuclear Information System (INIS)

    Chhabra, Avneesh; Faridian-Aragh, Neda; Chalian, Majid; Soldatos, Theodoros; Thawait, Shrey K.; Williams, Eric H.; Andreisek, Gustav

    2012-01-01

    The common peroneal nerve (CPN), a major terminal branch of the sciatic nerve, can be subject to a variety of pathologies, which may affect the nerve at any level from the lumbar plexus to its distal branches. Although the diagnosis of peripheral neuropathy is traditionally based on a patient's clinical findings and electrodiagnostic tests, magnetic resonance neurography (MRN) is gaining an increasing role in the definition of the type, site, and extent of peripheral nerve disorders. Current high-field MR scanners enable high-resolution and excellent soft-tissue contrast imaging of peripheral nerves. In the lower extremities, MR neurography has been employed in the demonstration of the anatomy and pathology of the CPN, as well as in the detection of associated secondary muscle denervation changes. This article reviews the normal appearance of the CPN as well as typical pathologies and abnormal findings at 3.0-T MR neurography of the lower extremity. (orig.)

  2. Meniscus tears of the knee: Postarthrogram high resolution CT

    International Nuclear Information System (INIS)

    Kim, Jae Hyoung; Do, Young Soo; You, Jin Jong; Gong, Jae Chul; Kim, Hyung Jin; Chung, Sung Hoon

    1990-01-01

    Thirty-eight knees with clinically suspected meniscal tears were examined with high resolution computed tomography(HRCT) immediately following double contrast arthrography. All subsequently underwent arthroscopy. The findings of postarthrogram HRCT and arthroscopy were compared to evaluated the usefulness of postarthrogram HRCT in diagnosis of the meniscal tears. The sensitivity, specificity and accuracy of HRCT were 96.2%. 83.3% and 92.1% respectively. The anatomic details of the meniscal tears were clearly visible on the HRCT scans. Sagittal and coronal reformation views well visualized the horizontal tears and the relationship of torn meniscal fragments, and well differential the peripheral tears from the synovial recess. Our result indicate that postarthrogram HRCT not only is a sensitive and effective method for the detection and characterization of the meniscal tears, but also provides arthroscopists with the appropriate surgical plans

  3. Quantitative high-resolution genomic analysis of single cancer cells.

    Science.gov (United States)

    Hannemann, Juliane; Meyer-Staeckling, Sönke; Kemming, Dirk; Alpers, Iris; Joosse, Simon A; Pospisil, Heike; Kurtz, Stefan; Görndt, Jennifer; Püschel, Klaus; Riethdorf, Sabine; Pantel, Klaus; Brandt, Burkhard

    2011-01-01

    During cancer progression, specific genomic aberrations arise that can determine the scope of the disease and can be used as predictive or prognostic markers. The detection of specific gene amplifications or deletions in single blood-borne or disseminated tumour cells that may give rise to the development of metastases is of great clinical interest but technically challenging. In this study, we present a method for quantitative high-resolution genomic analysis of single cells. Cells were isolated under permanent microscopic control followed by high-fidelity whole genome amplification and subsequent analyses by fine tiling array-CGH and qPCR. The assay was applied to single breast cancer cells to analyze the chromosomal region centred by the therapeutical relevant EGFR gene. This method allows precise quantitative analysis of copy number variations in single cell diagnostics.

  4. Quantitative high-resolution genomic analysis of single cancer cells.

    Directory of Open Access Journals (Sweden)

    Juliane Hannemann

    Full Text Available During cancer progression, specific genomic aberrations arise that can determine the scope of the disease and can be used as predictive or prognostic markers. The detection of specific gene amplifications or deletions in single blood-borne or disseminated tumour cells that may give rise to the development of metastases is of great clinical interest but technically challenging. In this study, we present a method for quantitative high-resolution genomic analysis of single cells. Cells were isolated under permanent microscopic control followed by high-fidelity whole genome amplification and subsequent analyses by fine tiling array-CGH and qPCR. The assay was applied to single breast cancer cells to analyze the chromosomal region centred by the therapeutical relevant EGFR gene. This method allows precise quantitative analysis of copy number variations in single cell diagnostics.

  5. High-resolution spectrum of the Galactic center

    Science.gov (United States)

    Mahoney, W. A.; Ling, J. C.; Wheaton, W. A.

    1993-01-01

    Recent observations of the Galactic center region indicate the presence of a narrow gamma-ray line feature at 170 keV, and theoretical speculations suggest it may result from Compton backscattering of the 511 keV annihilation radiation. The high-resolution gamma-ray spectrometer on HEAO 3 observed the Galactic center in the fall of 1979 and in the spring of 1980. In view of the recent developments, the HEAO data were re-examined to search for this new feature and to look for possible correlations with the 511 keV line emisison. No evidence for such Compton backscattered radiation was found and the derived upper limits for emission in a line feature near 170 keV were well below previously reported fluxes, indicating possible time variability.

  6. The inelastic contribution to high resolution images of defects

    International Nuclear Information System (INIS)

    Krivanek, O.L.; Ahn, C.C.; Wood, G.J.

    1990-01-01

    The importance of the contribution due to inelastically scattered electrons to unfiltered HREM images is examined, with emphasis on imaging of defects in semiconductors. Whenever the low energy loss spectrum contains sharp peaks, the contribution is not featureless. At specimen thickness of a few tens of nm, it may change the image appearance in a major way. The strongest effect occurs in high resolution, medium voltage (200 to 500 kV) electron microscope images of defects at focus values minimizing the contrast of the elastic image in low Z materials such as Al and Si. In higher Z materials or those with no sharp 'plasmons', the contribution is small. 23 refs., 8 figs

  7. High-Resolution Reciprocal Space Mapping for Characterizing Deformation Structures

    DEFF Research Database (Denmark)

    Pantleon, Wolfgang; Wejdemann, Christian; Jakobsen, Bo

    2014-01-01

    With high-angular resolution three-dimensional X-ray diffraction (3DXRD), quantitative information is gained about dislocation structures in individual grains in the bulk of a macroscopic specimen by acquiring reciprocal space maps. In high-resolution 3D reciprocal space maps of tensile......-deformed copper, individual, almost dislocation-free subgrains are identified from high-intensity peaks and distinguished by their unique combination of orientation and elastic strain; dislocation walls manifest themselves as a smooth cloud of lower intensity. The elastic strain shows only minor variations within...... dynamics is followed in situ during varying loading conditions by reciprocal space mapping: during uninterrupted tensile deformation, formation of subgrains is observed concurrently with broadening of Bragg reflections shortly after the onset of plastic deformation. When the traction is terminated, stress...

  8. Paracoccidioidomycosis: High-resolution computed tomography-pathologic correlation

    International Nuclear Information System (INIS)

    Marchiori, Edson; Valiante, Paulo Marcos; Mano, Claudia Mauro; Zanetti, Glaucia; Escuissato, Dante L.; Souza, Arthur Soares; Capone, Domenico

    2011-01-01

    Objective: The purpose of this study was to describe the high-resolution computed tomography (HRCT) features of pulmonary paracoccidioidomycosis and to correlate them with pathologic findings. Methods: The study included 23 adult patients with pulmonary paracoccidioidomycosis. All patients had undergone HRCT, and the images were retrospectively analyzed by two chest radiologists, who reached decisions by consensus. An experienced lung pathologist reviewed all pathological specimens. The HRCT findings were correlated with histopathologic data. Results: The predominant HRCT findings included areas of ground-glass opacities, nodules, interlobular septal thickening, airspace consolidation, cavitation, and fibrosis. The main pathological features consisted of alveolar and interlobular septal inflammatory infiltration, granulomas, alveolar exudate, cavitation secondary to necrosis, and fibrosis. Conclusion: Paracoccidioidomycosis can present different tomography patterns, which can involve both the interstitium and the airspace. These abnormalities can be pathologically correlated with inflammatory infiltration, granulomatous reaction, and fibrosis.

  9. High resolution imaging of tunnels by magnetic resonance neurography

    Energy Technology Data Exchange (ETDEWEB)

    Subhawong, Ty K.; Thawait, Shrey K.; Machado, Antonio J.; Carrino, John A.; Chhabra, Avneesh [Johns Hopkins Hospital, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Wang, Kenneth C. [Baltimore VA Medical Center, Department of Radiology, Baltimore, MD (United States); Williams, Eric H. [Dellon Institute for Peripheral Nerve Surgery, Towson, MD (United States); Hashemi, Shahreyar Shar [Johns Hopkins Hospital, Division of Plastic and Reconstructive Surgery, Baltimore, MD (United States)

    2012-01-15

    Peripheral nerves often traverse confined fibro-osseous and fibro-muscular tunnels in the extremities, where they are particularly vulnerable to entrapment and compressive neuropathy. This gives rise to various tunnel syndromes, characterized by distinct patterns of muscular weakness and sensory deficits. This article focuses on several upper and lower extremity tunnels, in which direct visualization of the normal and abnormal nerve in question is possible with high resolution 3T MR neurography (MRN). MRN can also serve as a useful adjunct to clinical and electrophysiologic exams by discriminating adhesive lesions (perineural scar) from compressive lesions (such as tumor, ganglion, hypertrophic callous, or anomalous muscles) responsible for symptoms, thereby guiding appropriate treatment. (orig.)

  10. High-resolution 3-T MR neurography of peroneal neuropathy

    Energy Technology Data Exchange (ETDEWEB)

    Chhabra, Avneesh; Faridian-Aragh, Neda; Chalian, Majid; Soldatos, Theodoros; Thawait, Shrey K. [Johns Hopkins Hospital, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Williams, Eric H. [Johns Hopkins Hospital, Department of Plastic Surgery, Baltimore, MD (United States); Dellon Institute for Peripheral Nerve Surgery, Baltimore, MD (United States); Andreisek, Gustav [University Hospital Zurich, Institute for Diagnostic Radiology, Department of Medical Radiology, Zurich (Switzerland)

    2012-03-15

    The common peroneal nerve (CPN), a major terminal branch of the sciatic nerve, can be subject to a variety of pathologies, which may affect the nerve at any level from the lumbar plexus to its distal branches. Although the diagnosis of peripheral neuropathy is traditionally based on a patient's clinical findings and electrodiagnostic tests, magnetic resonance neurography (MRN) is gaining an increasing role in the definition of the type, site, and extent of peripheral nerve disorders. Current high-field MR scanners enable high-resolution and excellent soft-tissue contrast imaging of peripheral nerves. In the lower extremities, MR neurography has been employed in the demonstration of the anatomy and pathology of the CPN, as well as in the detection of associated secondary muscle denervation changes. This article reviews the normal appearance of the CPN as well as typical pathologies and abnormal findings at 3.0-T MR neurography of the lower extremity. (orig.)

  11. High resolution imaging of tunnels by magnetic resonance neurography

    International Nuclear Information System (INIS)

    Subhawong, Ty K.; Thawait, Shrey K.; Machado, Antonio J.; Carrino, John A.; Chhabra, Avneesh; Wang, Kenneth C.; Williams, Eric H.; Hashemi, Shahreyar Shar

    2012-01-01

    Peripheral nerves often traverse confined fibro-osseous and fibro-muscular tunnels in the extremities, where they are particularly vulnerable to entrapment and compressive neuropathy. This gives rise to various tunnel syndromes, characterized by distinct patterns of muscular weakness and sensory deficits. This article focuses on several upper and lower extremity tunnels, in which direct visualization of the normal and abnormal nerve in question is possible with high resolution 3T MR neurography (MRN). MRN can also serve as a useful adjunct to clinical and electrophysiologic exams by discriminating adhesive lesions (perineural scar) from compressive lesions (such as tumor, ganglion, hypertrophic callous, or anomalous muscles) responsible for symptoms, thereby guiding appropriate treatment. (orig.)

  12. High resolution photoelectron spectroscopy of clusters of Group V elements

    International Nuclear Information System (INIS)

    Wang, Lai-sheng; Niu, B.; Lee, Y.T.; Shirley, D.A.

    1989-07-01

    High resolution HeI (580 angstrom) photoelectron spectra of As 2 , As 4 , and P 4 were obtained with a newly-built high temperature molecular beam source. Vibrational structure was resolved in the photoelectron spectra of the three cluster species. The Jahn-Teller effect is discussed for the 2 E and 2 T 2 states of P 4 + and As 4 + . As a result of the Jahn-Teller effect, the 2 E state splits into two bands, and the 2 T 2 state splits into three bands, in combination with the spin-orbit effect. It was observed that the ν 2 normal vibrational mode was involved in the vibronic interaction of the 2 E state, while both the ν 2 and ν 3 modes were active in the 2 T 2 state. 26 refs., 5 figs., 3 tabs

  13. Chandra High Resolution Imaging of NGC 1365 and NGC 4151

    Science.gov (United States)

    Wang, Junfeng; Fabbiano, G.; Elvis, M.; Risaliti, G.; Karovska, M.; Zezas, A.; Mazzarella, J. M.; Lord, S.; Howell, J. H.; Mundell, C. G.

    2010-07-01

    We present Chandra high resolution imaging of the circumnuclear regions of two nearby active galaxies, namely the starburst/AGN composite Seyfert 1.8 NGC 1365 and the archetypal Seyfert 1 NGC 4151. In NGC 1365, the X-ray morphology shows a biconical soft X-ray-emission region extending ~5 kpc in projection from the nucleus, coincident with the optical high-excitation outflows. Chandra HRC imaging of the NGC 4151 nucleus resolves X-ray emission from the 4 arcsec radio jet and the narrow line region (NLR) clouds. Our results demonstrate the unique power of spatially resolved spectroscopy with Chandra, and support previous claims that frequent jet-ISM interaction may explain why jets in Seyfert galaxies appear small, slow, and thermally dominated.

  14. High resolution ultrastructure imaging of fractures in human dental tissues

    Directory of Open Access Journals (Sweden)

    Tan Sui

    2014-01-01

    Full Text Available Human dental hard tissues are dentine, cementum, and enamel. These are hydrated mineralised composite tissues with a hierarchical structure and versatile thermo-mechanical properties. The hierarchical structure of dentine and enamel was imaged by transmission electron microscopy (TEM of samples prepared by focused ion beam (FIB milling. High resolution TEM was carried out in the vicinity of a crack tip in dentine. An intricate “random weave” pattern of hydroxyapatile crystallites was observed and this provided a possible explanation for toughening of the mineralized dentine tissue at the nano-scale. The results reported here provide the basis for improved understanding of the relationship between the multi-scale nature and the mechanical properties of hierarchically structured biomaterials, and will also be useful for the development of better prosthetic and dental restorative materials.

  15. A high resolution gridded ionization chamber for nuclear spectroscopy

    International Nuclear Information System (INIS)

    Vitale, E.R.

    1988-01-01

    This paper describes some techniques used in the design of high resolution gridded ionisation chambers for measurements of absolute activity of radionuclides. Details of the geometry of the system and its electrodes are presented; their shape and the spacing between the grid wire was studied with the help of an electrolytic tank. The experimental spectra obtained with an Am 241 source using Ar + 10% methane as a flow gas show a total resolution of 39,07 KeV in very good agreement with the best results available in the literature. An application of the methods developed was used in the design ans construction of a proportional counter provided with three sequential grids disposed in such a way that the pulses from the first stage had their amplitude multiplied by the two further stages. Multiplication factors of the order of 10 sup(3) were obtained but higher values are expected. (author)

  16. Evaluation of Esophageal Motor Function With High-resolution Manometry

    Science.gov (United States)

    2013-01-01

    For several decades esophageal manometry has been the test of choice to evaluate disorders of esophageal motor function. The recent introduction of high-resolution manometry for the study of esophageal motor function simplified performance of esophageal manometry, and revealed previously unidentified patterns of normal and abnormal esophageal motor function. Presentation of pressure data as color contour plots or esophageal pressure topography led to the development of new tools for analyzing and classifying esophageal motor patterns. The current standard and still developing approach to do this is the Chicago classification. While this methodical approach is improving our diagnosis of esophageal motor disorders, it currently does not address all motor abnormalities. We will explore the Chicago classification and disorders that it does not address. PMID:23875094

  17. High resolution imaging of surface patterns of single bacterial cells

    International Nuclear Information System (INIS)

    Greif, Dominik; Wesner, Daniel; Regtmeier, Jan; Anselmetti, Dario

    2010-01-01

    We systematically studied the origin of surface patterns observed on single Sinorhizobium meliloti bacterial cells by comparing the complementary techniques atomic force microscopy (AFM) and scanning electron microscopy (SEM). Conditions ranged from living bacteria in liquid to fixed bacteria in high vacuum. Stepwise, we applied different sample modifications (fixation, drying, metal coating, etc.) and characterized the observed surface patterns. A detailed analysis revealed that the surface structure with wrinkled protrusions in SEM images were not generated de novo but most likely evolved from similar and naturally present structures on the surface of living bacteria. The influence of osmotic stress to the surface structure of living cells was evaluated and also the contribution of exopolysaccharide and lipopolysaccharide (LPS) by imaging two mutant strains of the bacterium under native conditions. AFM images of living bacteria in culture medium exhibited surface structures of the size of single proteins emphasizing the usefulness of AFM for high resolution cell imaging.

  18. Bayesian Peptide Peak Detection for High Resolution TOF Mass Spectrometry.

    Science.gov (United States)

    Zhang, Jianqiu; Zhou, Xiaobo; Wang, Honghui; Suffredini, Anthony; Zhang, Lin; Huang, Yufei; Wong, Stephen

    2010-11-01

    In this paper, we address the issue of peptide ion peak detection for high resolution time-of-flight (TOF) mass spectrometry (MS) data. A novel Bayesian peptide ion peak detection method is proposed for TOF data with resolution of 10 000-15 000 full width at half-maximum (FWHW). MS spectra exhibit distinct characteristics at this resolution, which are captured in a novel parametric model. Based on the proposed parametric model, a Bayesian peak detection algorithm based on Markov chain Monte Carlo (MCMC) sampling is developed. The proposed algorithm is tested on both simulated and real datasets. The results show a significant improvement in detection performance over a commonly employed method. The results also agree with expert's visual inspection. Moreover, better detection consistency is achieved across MS datasets from patients with identical pathological condition.

  19. High-resolution imaging of solar system objects

    International Nuclear Information System (INIS)

    Goldberg, B.A.

    1988-01-01

    The strategy of this investigation has been to develop new high-resolution imaging capabilities and to apply them to extended observing programs. These programs have included Io's neutral sodium cloud and comets. The Io observing program was carried out at Table Mountain Observatory (1976 to 1981), providing a framework interpreting Voyager measurements of the Io torus, and serving as an important reference for studying asymmetries and time variabilities in the Jovian magnetosphere. Comet observations made with the 3.6 m Canada-France-Hawaii Telescope and 1.6 m AMOS telescope (1984 to 1987) provide basis for studying early coma development in Halley, the kinematics of its nucleus, and the internal and external structure of the nucleus. Images of GZ from the ICE encounter period form the basis for unique comparisons with in situ magnetic field and dust impact measurements to determine the ion tail and dust coma structure, respectively

  20. Polystyrene negative resist for high-resolution electron beam lithography

    Directory of Open Access Journals (Sweden)

    Ma Siqi

    2011-01-01

    Full Text Available Abstract We studied the exposure behavior of low molecular weight polystyrene as a negative tone electron beam lithography (EBL resist, with the goal of finding the ultimate achievable resolution. It demonstrated fairly well-defined patterning of a 20-nm period line array and a 15-nm period dot array, which are the densest patterns ever achieved using organic EBL resists. Such dense patterns can be achieved both at 20 and 5 keV beam energies using different developers. In addition to its ultra-high resolution capability, polystyrene is a simple and low-cost resist with easy process control and practically unlimited shelf life. It is also considerably more resistant to dry etching than PMMA. With a low sensitivity, it would find applications where negative resist is desired and throughput is not a major concern.

  1. Performance of a high resolution cavity beam position monitor system

    Science.gov (United States)

    Walston, Sean; Boogert, Stewart; Chung, Carl; Fitsos, Pete; Frisch, Joe; Gronberg, Jeff; Hayano, Hitoshi; Honda, Yosuke; Kolomensky, Yury; Lyapin, Alexey; Malton, Stephen; May, Justin; McCormick, Douglas; Meller, Robert; Miller, David; Orimoto, Toyoko; Ross, Marc; Slater, Mark; Smith, Steve; Smith, Tonee; Terunuma, Nobuhiro; Thomson, Mark; Urakawa, Junji; Vogel, Vladimir; Ward, David; White, Glen

    2007-07-01

    It has been estimated that an RF cavity Beam Position Monitor (BPM) could provide a position measurement resolution of less than 1 nm. We have developed a high resolution cavity BPM and associated electronics. A triplet comprised of these BPMs was installed in the extraction line of the Accelerator Test Facility (ATF) at the High Energy Accelerator Research Organization (KEK) for testing with its ultra-low emittance beam. The three BPMs were each rigidly mounted inside an alignment frame on six variable-length struts which could be used to move the BPMs in position and angle. We have developed novel methods for extracting the position and tilt information from the BPM signals including a robust calibration algorithm which is immune to beam jitter. To date, we have demonstrated a position resolution of 15.6 nm and a tilt resolution of 2.1 μrad over a dynamic range of approximately ±20 μm.

  2. High resolution 3D imaging of synchrotron generated microbeams

    Energy Technology Data Exchange (ETDEWEB)

    Gagliardi, Frank M., E-mail: frank.gagliardi@wbrc.org.au [Alfred Health Radiation Oncology, The Alfred, Melbourne, Victoria 3004, Australia and School of Medical Sciences, RMIT University, Bundoora, Victoria 3083 (Australia); Cornelius, Iwan [Imaging and Medical Beamline, Australian Synchrotron, Clayton, Victoria 3168, Australia and Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales 2500 (Australia); Blencowe, Anton [Division of Health Sciences, School of Pharmacy and Medical Sciences, The University of South Australia, Adelaide, South Australia 5000, Australia and Division of Information Technology, Engineering and the Environment, Mawson Institute, University of South Australia, Mawson Lakes, South Australia 5095 (Australia); Franich, Rick D. [School of Applied Sciences and Health Innovations Research Institute, RMIT University, Melbourne, Victoria 3000 (Australia); Geso, Moshi [School of Medical Sciences, RMIT University, Bundoora, Victoria 3083 (Australia)

    2015-12-15

    Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy. Methods: Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25–50 μm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a NIKON A1 laser fluorescence confocal microscope. Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 μm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured. Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery.

  3. Evaluation of a High-Resolution Regional Reanalysis for Europe

    Science.gov (United States)

    Ohlwein, C.; Wahl, S.; Keller, J. D.; Bollmeyer, C.

    2014-12-01

    Reanalyses gain more and more importance as a source of meteorological information for many purposes and applications. Several global reanalyses projects (e.g., ERA, MERRA, CSFR, JMA9) produce and verify these data sets to provide time series as long as possible combined with a high data quality. Due to a spatial resolution down to 50-70km and 3-hourly temporal output, they are not suitable for small scale problems (e.g., regional climate assessment, meso-scale NWP verification, input for subsequent models such as river runoff simulations). The implementation of regional reanalyses based on a limited area model along with a data assimilation scheme is able to generate reanalysis data sets with high spatio-temporal resolution. Within the Hans-Ertel-Centre for Weather Research (HErZ), the climate monitoring branch concentrates efforts on the assessment and analysis of regional climate in Germany and Europe. In joint cooperation with DWD (German Meteorological Service), a high-resolution reanalysis system based on the COSMO model has been developed. The regional reanalysis for Europe matches the domain of the CORDEX EURO-11 specifications, albeit at a higher spatial resolution, i.e., 0.055° (6km) instead of 0.11° (12km) and comprises the assimilation of observational data using the existing nudging scheme of COSMO complemented by a special soil moisture analysis with boundary conditions provided by ERA-Interim data. The reanalysis data set covers 6 years (2007-2012) and is currently extended to 16 years. Extensive evaluation of the reanalysis is performed using independent observations with special emphasis on precipitation and high-impact weather situations indicating a better representation of small scale variability. Further, the evaluation shows an added value of the regional reanalysis with respect to the forcing ERA Interim reanalysis and compared to a pure high-resolution dynamical downscaling approach without data assimilation.

  4. The high-resolution regional reanalysis COSMO-REA6

    Science.gov (United States)

    Ohlwein, C.

    2016-12-01

    Reanalyses gain more and more importance as a source of meteorological information for many purposes and applications. Several global reanalyses projects (e.g., ERA, MERRA, CSFR, JMA9) produce and verify these data sets to provide time series as long as possible combined with a high data quality. Due to a spatial resolution down to 50-70km and 3-hourly temporal output, they are not suitable for small scale problems (e.g., regional climate assessment, meso-scale NWP verification, input for subsequent models such as river runoff simulations). The implementation of regional reanalyses based on a limited area model along with a data assimilation scheme is able to generate reanalysis data sets with high spatio-temporal resolution. Within the Hans-Ertel-Centre for Weather Research (HErZ), the climate monitoring branch concentrates efforts on the assessment and analysis of regional climate in Germany and Europe. In joint cooperation with DWD (German Meteorological Service), a high-resolution reanalysis system based on the COSMO model has been developed. The regional reanalysis for Europe matches the domain of the CORDEX EURO-11 specifications, albeit at a higher spatial resolution, i.e., 0.055° (6km) instead of 0.11° (12km) and comprises the assimilation of observational data using the existing nudging scheme of COSMO complemented by a special soil moisture analysis with boundary conditions provided by ERA-Interim data. The reanalysis data set covers the past 20 years. Extensive evaluation of the reanalysis is performed using independent observations with special emphasis on precipitation and high-impact weather situations indicating a better representation of small scale variability. Further, the evaluation shows an added value of the regional reanalysis with respect to the forcing ERA Interim reanalysis and compared to a pure high-resolution dynamical downscaling approach without data assimilation.

  5. A High-resolution Reanalysis for the European CORDEX Region

    Science.gov (United States)

    Bentzien, Sabrina; Bollmeyer, Christoph; Crewell, Susanne; Friederichs, Petra; Hense, Andreas; Keller, Jan; Keune, Jessica; Kneifel, Stefan; Ohlwein, Christian; Pscheidt, Ieda; Redl, Stephanie; Steinke, Sandra

    2014-05-01

    A High-resolution Reanalysis for the European CORDEX Region Within the Hans-Ertel-Centre for Weather Research (HErZ), the climate monitoring branch concentrates efforts on the assessment and analysis of regional climate in Germany and Europe. In joint cooperation with DWD (German Meteorological Service), a high-resolution reanalysis system based on the COSMO model has been developed. Reanalyses gain more and more importance as a source of meteorological information for many purposes and applications. Several global reanalyses projects (e.g., ERA, MERRA, CSFR, JMA9) produce and verify these data sets to provide time series as long as possible combined with a high data quality. Due to a spatial resolution down to 50-70km and 3-hourly temporal output, they are not suitable for small scale problems (e.g., regional climate assessment, meso-scale NWP verification, input for subsequent models such as river runoff simulations). The implementation of regional reanalyses based on a limited area model along with a data assimilation scheme is able to generate reanalysis data sets with high spatio-temporal resolution. The work presented here focuses on the regional reanalysis for Europe with a domain matching the CORDEX-EURO-11 specifications, albeit at a higher spatial resolution, i.e., 0.055° (6km) instead of 0.11° (12km). The COSMO reanalysis system comprises the assimilation of observational data using the existing nudging scheme of COSMO and is complemented by a special soil moisture analysis and boundary conditions given by ERA-interim data. The reanalysis data set currently covers 6 years (2007-2012). The evaluation of the reanalyses is done using independent observations with special emphasis on precipitation and high-impact weather situations. The development and evaluation of the COSMO-based reanalysis for the CORDEX-Euro domain can be seen as a preparation for joint European activities on the development of an ensemble system of regional reanalyses for Europe.

  6. A high-resolution regional reanalysis for Europe

    Science.gov (United States)

    Ohlwein, C.

    2015-12-01

    Reanalyses gain more and more importance as a source of meteorological information for many purposes and applications. Several global reanalyses projects (e.g., ERA, MERRA, CSFR, JMA9) produce and verify these data sets to provide time series as long as possible combined with a high data quality. Due to a spatial resolution down to 50-70km and 3-hourly temporal output, they are not suitable for small scale problems (e.g., regional climate assessment, meso-scale NWP verification, input for subsequent models such as river runoff simulations). The implementation of regional reanalyses based on a limited area model along with a data assimilation scheme is able to generate reanalysis data sets with high spatio-temporal resolution. Within the Hans-Ertel-Centre for Weather Research (HErZ), the climate monitoring branch concentrates efforts on the assessment and analysis of regional climate in Germany and Europe. In joint cooperation with DWD (German Meteorological Service), a high-resolution reanalysis system based on the COSMO model has been developed. The regional reanalysis for Europe matches the domain of the CORDEX EURO-11 specifications, albeit at a higher spatial resolution, i.e., 0.055° (6km) instead of 0.11° (12km) and comprises the assimilation of observational data using the existing nudging scheme of COSMO complemented by a special soil moisture analysis with boundary conditions provided by ERA-Interim data. The reanalysis data set covers the past 20 years. Extensive evaluation of the reanalysis is performed using independent observations with special emphasis on precipitation and high-impact weather situations indicating a better representation of small scale variability. Further, the evaluation shows an added value of the regional reanalysis with respect to the forcing ERA Interim reanalysis and compared to a pure high-resolution dynamical downscaling approach without data assimilation.

  7. High-resolution RCMs as pioneers for future GCMs

    Science.gov (United States)

    Schar, C.; Ban, N.; Arteaga, A.; Charpilloz, C.; Di Girolamo, S.; Fuhrer, O.; Hoefler, T.; Leutwyler, D.; Lüthi, D.; Piaget, N.; Ruedisuehli, S.; Schlemmer, L.; Schulthess, T. C.; Wernli, H.

    2017-12-01

    Currently large efforts are underway to refine the horizontal resolution of global and regional climate models to O(1 km), with the intent to represent convective clouds explicitly rather than using semi-empirical parameterizations. This refinement will move the governing equations closer to first principles and is expected to reduce the uncertainties of climate models. High resolution is particularly attractive in order to better represent critical cloud feedback processes (e.g. related to global climate sensitivity and extratropical summer convection) and extreme events (such as heavy precipitation events, floods, and hurricanes). The presentation will be illustrated using decade-long simulations at 2 km horizontal grid spacing, some of these covering the European continent on a computational mesh with 1536x1536x60 grid points. To accomplish such simulations, use is made of emerging heterogeneous supercomputing architectures, using a version of the COSMO limited-area weather and climate model that is able to run entirely on GPUs. Results show that kilometer-scale resolution dramatically improves the simulation of precipitation in terms of the diurnal cycle and short-term extremes. The modeling framework is used to address changes of precipitation scaling with climate change. It is argued that already today, modern supercomputers would in principle enable global atmospheric convection-resolving climate simulations, provided appropriately refactored codes were available, and provided solutions were found to cope with the rapidly growing output volume. A discussion will be provided of key challenges affecting the design of future high-resolution climate models. It is suggested that km-scale RCMs should be exploited to pioneer this terrain, at a time when GCMs are not yet available at such resolutions. Areas of interest include the development of new parameterization schemes adequate for km-scale resolution, the exploration of new validation methodologies and data

  8. A high-resolution multimode digital microscope system.

    Science.gov (United States)

    Salmon, Edward D; Shaw, Sidney L; Waters, Jennifer C; Waterman-Storer, Clare M; Maddox, Paul S; Yeh, Elaine; Bloom, Kerry

    2013-01-01

    This chapter describes the development of a high-resolution, multimode digital imaging system based on a wide-field epifluorescent and transmitted light microscope, and a cooled charge-coupled device (CCD) camera. The three main parts of this imaging system are Nikon FXA microscope, Hamamatsu C4880 cooled CCD camera, and MetaMorph digital imaging system. This chapter presents various design criteria for the instrument and describes the major features of the microscope components-the cooled CCD camera and the MetaMorph digital imaging system. The Nikon FXA upright microscope can produce high resolution images for both epifluorescent and transmitted light illumination without switching the objective or moving the specimen. The functional aspects of the microscope set-up can be considered in terms of the imaging optics, the epi-illumination optics, the transillumination optics, the focus control, and the vibration isolation table. This instrument is somewhat specialized for microtubule and mitosis studies, and it is also applicable to a variety of problems in cellular imaging, including tracking proteins fused to the green fluorescent protein in live cells. The instrument is also valuable for correlating the assembly dynamics of individual cytoplasmic microtubules (labeled by conjugating X-rhodamine to tubulin) with the dynamics of membranes of the endoplasmic reticulum (labeled with DiOC6) and the dynamics of the cell cortex (by differential interference contrast) in migrating vertebrate epithelial cells. This imaging system also plays an important role in the analysis of mitotic mutants in the powerful yeast genetic system Saccharomyces cerevisiae. Copyright © 1998 Elsevier Inc. All rights reserved.

  9. Enhancing GIS Capabilities for High Resolution Earth Science Grids

    Science.gov (United States)

    Koziol, B. W.; Oehmke, R.; Li, P.; O'Kuinghttons, R.; Theurich, G.; DeLuca, C.

    2017-12-01

    Applications for high performance GIS will continue to increase as Earth system models pursue more realistic representations of Earth system processes. Finer spatial resolution model input and output, unstructured or irregular modeling grids, data assimilation, and regional coordinate systems present novel challenges for GIS frameworks operating in the Earth system modeling domain. This presentation provides an overview of two GIS-driven applications that combine high performance software with big geospatial datasets to produce value-added tools for the modeling and geoscientific community. First, a large-scale interpolation experiment using National Hydrography Dataset (NHD) catchments, a high resolution rectilinear CONUS grid, and the Earth System Modeling Framework's (ESMF) conservative interpolation capability will be described. ESMF is a parallel, high-performance software toolkit that provides capabilities (e.g. interpolation) for building and coupling Earth science applications. ESMF is developed primarily by the NOAA Environmental Software Infrastructure and Interoperability (NESII) group. The purpose of this experiment was to test and demonstrate the utility of high performance scientific software in traditional GIS domains. Special attention will be paid to the nuanced requirements for dealing with high resolution, unstructured grids in scientific data formats. Second, a chunked interpolation application using ESMF and OpenClimateGIS (OCGIS) will demonstrate how spatial subsetting can virtually remove computing resource ceilings for very high spatial resolution interpolation operations. OCGIS is a NESII-developed Python software package designed for the geospatial manipulation of high-dimensional scientific datasets. An overview of the data processing workflow, why a chunked approach is required, and how the application could be adapted to meet operational requirements will be discussed here. In addition, we'll provide a general overview of OCGIS

  10. COMPARATIVE ASSESSMENT OF VERY HIGH RESOLUTION SATELLITE AND AERIAL ORTHOIMAGERY

    Directory of Open Access Journals (Sweden)

    P. Agrafiotis

    2015-03-01

    Full Text Available This paper aims to assess the accuracy and radiometric quality of orthorectified high resolution satellite imagery from Pleiades-1B satellites through a comparative evaluation of their quantitative and qualitative properties. A Pleiades-B1 stereopair of high resolution images taken in 2013, two adjacent GeoEye-1 stereopairs from 2011 and aerial orthomosaic (LSO provided by NCMA S.A (Hellenic Cadastre from 2007 have been used for the comparison tests. As control dataset orthomosaic from aerial imagery provided also by NCMA S.A (0.25m GSD from 2012 was selected. The process for DSM and orthoimage production was performed using commercial digital photogrammetric workstations. The two resulting orthoimages and the aerial orthomosaic (LSO were relatively and absolutely evaluated for their quantitative and qualitative properties. Test measurements were performed using the same check points in order to establish their accuracy both as far as the single point coordinates as well as their distances are concerned. Check points were distributed according to JRC Guidelines for Best Practice and Quality Checking of Ortho Imagery and NSSDA standards while areas with different terrain relief and land cover were also included. The tests performed were based also on JRC and NSSDA accuracy standards. Finally, tests were carried out in order to assess the radiometric quality of the orthoimagery. The results are presented with a statistical analysis and they are evaluated in order to present the merits and demerits of the imaging sensors involved for orthoimage production. The results also serve for a critical approach for the usability and cost efficiency of satellite imagery for the production of Large Scale Orthophotos.

  11. High resolution micro ultrasonic machining for trimming 3D microstructures

    International Nuclear Information System (INIS)

    Viswanath, Anupam; Li, Tao; Gianchandani, Yogesh

    2014-01-01

    This paper reports on the evaluation of a high resolution micro ultrasonic machining (HR-µUSM) process suitable for post fabrication trimming of complex 3D microstructures made from fused silica. Unlike conventional USM, the HR-µUSM process aims for low machining rates, providing high resolution and high surface quality. The machining rate is reduced by keeping the micro-tool tip at a fixed distance from the workpiece and vibrating it at a small amplitude. The surface roughness is improved by an appropriate selection of abrasive particles. Fluidic modeling is performed to study interaction among the vibrating micro-tool tip, workpiece, and the slurry. Using 304 stainless steel (SS304) tool tips of 50 µm diameter, the machining performance of the HR-µUSM process is characterized on flat fused silica substrates. The depths and surface finish of machined features are evaluated as functions of slurry concentrations, separation between the micro-tool and workpiece, and machining time. Under the selected conditions, the HR-µUSM process achieves machining rates as low as 10 nm s −1  averaged over the first minute of machining of a flat virgin sample. This corresponds to a mass removal rate of ≈20 ng min −1 . The average surface roughness, S a , achieved is as low as 30 nm. Analytical and numerical modeling are used to explain the typical profile of the machined features as well as machining rates. The process is used to demonstrate trimming of hemispherical 3D shells made of fused silica. (paper)

  12. High resolution 3D imaging of synchrotron generated microbeams

    International Nuclear Information System (INIS)

    Gagliardi, Frank M.; Cornelius, Iwan; Blencowe, Anton; Franich, Rick D.; Geso, Moshi

    2015-01-01

    Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy. Methods: Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25–50 μm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a NIKON A1 laser fluorescence confocal microscope. Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 μm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured. Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery

  13. High resolution microphotonic needle for endoscopic imaging (Conference Presentation)

    Science.gov (United States)

    Tadayon, Mohammad Amin; Mohanty, Aseema; Roberts, Samantha P.; Barbosa, Felippe; Lipson, Michal

    2017-02-01

    GRIN (Graded index) lens have revolutionized micro endoscopy enabling deep tissue imaging with high resolution. The challenges of traditional GRIN lenses are their large size (when compared with the field of view) and their limited resolution. This is because of the relatively weak NA in standard graded index lenses. Here we introduce a novel micro-needle platform for endoscopy with much higher resolution than traditional GRIN lenses and a FOV that corresponds to the whole cross section of the needle. The platform is based on polymeric (SU-8) waveguide integrated with a microlens micro fabricated on a silicon substrate using a unique molding process. Due to the high index of refraction of the material the NA of the needle is much higher than traditional GRIN lenses. We tested the probe in a fluorescent dye solution (19.6 µM Alexa Flour 647 solution) and measured a numerical aperture of 0.25, focal length of about 175 µm and minimal spot size of about 1.6 µm. We show that the platform can image a sample with the field of view corresponding to the cross sectional area of the waveguide (80x100 µm2). The waveguide size can in principle be modified to vary size of the imaging field of view. This demonstration, combined with our previous work demonstrating our ability to implant the high NA needle in a live animal, shows that the proposed system can be used for deep tissue imaging with very high resolution and high field of view.

  14. An integrated platform for simultaneous multi-well field potential recording and Fura-2-based calcium transient ratiometry in human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes.

    Science.gov (United States)

    Rast, Georg; Weber, Jürgen; Disch, Christoph; Schuck, Elmar; Ittrich, Carina; Guth, Brian D

    2015-01-01

    Human induced pluripotent stem cell-derived cardiomyocytes are available from various sources and they are being evaluated for safety testing. Several platforms are available offering different assay principles and read-out parameters: patch-clamp and field potential recording, imaging or photometry, impedance measurement, and recording of contractile force. Routine use will establish which assay principle and which parameters best serve the intended purpose. We introduce a combination of field potential recording and calcium ratiometry from spontaneously beating cardiomyocytes as a novel assay providing a complementary read-out parameter set. Field potential recording is performed using a commercial multi-well multi-electrode array platform. Calcium ratiometry is performed using a fiber optic illumination and silicon avalanche photodetectors. Data condensation and statistical analysis are designed to enable statistical inference of differences and equivalence with regard to a solvent control. Simultaneous recording of field potentials and calcium transients from spontaneously beating monolayers was done in a nine-well format. Calcium channel blockers (e.g. nifedipine) and a blocker of calcium store release (ryanodine) can be recognized and discriminated based on the calcium transient signal. An agonist of L-type calcium channels, FPL 64176, increased and prolonged the calcium transient, whereas BAY K 8644, another L-type calcium channel agonist, had no effect. Both FPL 64176 and various calcium channel antagonists have chronotropic effects, which can be discriminated from typical "chronotropic" compounds, like (±)isoprenaline (positive) and arecaidine propargyl ester (negative), based on their effects on the calcium transient. Despite technical limitations in temporal resolution and exact matching of composite calcium transient with the field potential of a subset of cells, the combined recording platform enables a refined interpretation of the field potential

  15. Strengthening IAEA safeguards using high-resolution commercial satellite imagery

    International Nuclear Information System (INIS)

    Zhang Hui

    2001-01-01

    Full text: In May 1997, the IAEA Board of Governors adopted the Additional Safeguards Protocol to improve its ability to detect the undeclared production of fissile material. This new strengthened safeguards system has opened the door for the IAEA to use of all types of information, including the potential use of commercial satellite imagery. We have therefore been investigating the feasibility of strengthening IAEA safeguards using commercial satellite imagery. Based on our analysis on a number of one-meter resolution IKONOS satellite images of military nuclear production facilities at nuclear states including Russia, China, India, Pakistan and Israel, we found that the new high-resolution commercial satellite imagery would play a new and valuable role in strengthening IAEA safeguards. Since 1999, images with a resolution of one meter have been available commercially from Space Imaging's IKONOS satellite. One-meter images from other companies are expected to enter the market soon. Although still an order of magnitude less capable than military imaging satellites, the capabilities of these new high-resolution commercial satellites are good enough to detect and identify the major visible characteristics of nuclear production facilities and sites. Unlike the classified spy satellite photos limited to few countries, the commercial satellite imagery is commercially available to anyone who wants to purchase it. Therefore, the new commercial satellite open a new chance that each state, international organizations, and non-governmental groups could use the commercial images to play a more proactive role in monitoring the nuclear activities in related countries and verifying the compliance of non-proliferation agreements. This could help galvanize support for intensified efforts to slow the pace of nuclear proliferation. To produce fissile materials (plutonium and highly enriched uranium) for weapons, a country would operate dedicated plutonium-production reactors and the

  16. High-Resolution UV Relay Lens for Particle Size Distribution Measurements Using Holography

    Energy Technology Data Exchange (ETDEWEB)

    Malone, Robert M.; Capelle, Gene A.; Frogget, Brent C.; Grover, Mike; Kaufman, Morris I.; Pazuchanics, Peter; Sorenson, Danny S.; Stevens, Gerald D.; Tibbits, Aric; Turley, William D.

    2008-08-29

    Shock waves passing through a metal sample can produce ejecta particulates at a metal-vacuum interface. Holography records particle size distributions by using a high-power, short-pulse laser to freeze particle motion. The sizes of the ejecta particles are recorded using an in-line Fraunhofer holography technique. Because the holographic plate would be destroyed in an energetic environment, a high-resolution lens has been designed to relay the interference fringes to a safe environment. Particle sizes within a 12-mm-diameter, 5-mm-thick volume are recorded onto holographic film. To achieve resolution down to 0.5 μm, ultraviolet laser (UV) light is needed. The design and assembly of a nine-element lens that achieves >2000 lp/mm resolution and operates at f/0.89 will be described. To set up this lens system, a doublet lens is temporarily attached that enables operation with 532-nm laser light and 1100 lp/mm resolution. Thus, the setup and alignment are performed with green light, but the dynamic recording is done with UV light. During setup, the 532-nm beam provides enough focus shift to accommodate the placement of a resolution target outside the ejecta volume; this resolution target does not interfere with the calibrated wires and pegs surrounding the ejecta volume. A television microscope archives images of resolution patterns that prove that the calibration wires, interference filter, holographic plate, and relay lenses are in their correct positions. Part of this lens is under vacuum, at the point where the laser illumination passes through a focus. Alignment and tolerancing of this high-resolution lens will be presented, and resolution variation through the 5-mm depth of field will be discussed.

  17. WRF high resolution dynamical downscaling of ERA-Interim for Portugal

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Pedro M.M. [University of Lisbon, Instituto Dom Luiz, Lisbon (Portugal); Faculdade de Ciencias da Universidade de Lisboa, Lisbon (Portugal); Cardoso, Rita M.; Miranda, Pedro M.A.; Medeiros, Joana de [University of Lisbon, Instituto Dom Luiz, Lisbon (Portugal); Belo-Pereira, Margarida; Espirito-Santo, Fatima [Instituto de Meteorologia, Lisbon (Portugal)

    2012-11-15

    This study proposes a dynamically downscaled climatology of Portugal, produced by a high resolution (9 km) WRF simulation, forced by 20 years of ERA-Interim reanalysis (1989-2008), nested in an intermediate domain with 27 km of resolution. The Portuguese mainland is characterized by large precipitation gradients, with observed mean annual precipitation ranging from about 400 to over 2,200 mm, with a very wet northwest and rather dry southeast, largely explained by orographic processes. Model results are compared with all available stations with continuous records, comprising daily information in 32 stations for temperature and 308 for precipitation, through the computation of mean climatologies, standard statistical errors on daily to seasonally timescales, and distributions of extreme events. Results show that WRF at 9 km outperforms ERA-Interim in all analyzed variables, with good results in the representation of the annual cycles in each region. The biases of minimum and maximum temperature are reduced, with improvement of the description of temperature variability at the extreme range of its distribution. The largest gain of the high resolution simulations is visible in the rainiest regions of Portugal, where orographic enhancement is crucial. These improvements are striking in the high ranking percentiles in all seasons, describing extreme precipitation events. WRF results at 9 km compare favorably with published results supporting its use as a high-resolution regional climate model. This higher resolution allows a better representation of extreme events that are of major importance to develop mitigation/adaptation strategies by policy makers and downstream users of regional climate models in applications such as flash floods or heat waves. (orig.)

  18. Enhancing Conservation with High Resolution Productivity Datasets for the Conterminous United States

    Science.gov (United States)

    Robinson, Nathaniel Paul

    Human driven alteration of the earth's terrestrial surface is accelerating through land use changes, intensification of human activity, climate change, and other anthropogenic pressures. These changes occur at broad spatio-temporal scales, challenging our ability to effectively monitor and assess the impacts and subsequent conservation strategies. While satellite remote sensing (SRS) products enable monitoring of the earth's terrestrial surface continuously across space and time, the practical applications for conservation and management of these products are limited. Often the processes driving ecological change occur at fine spatial resolutions and are undetectable given the resolution of available datasets. Additionally, the links between SRS data and ecologically meaningful metrics are weak. Recent advances in cloud computing technology along with the growing record of high resolution SRS data enable the development of SRS products that quantify ecologically meaningful variables at relevant scales applicable for conservation and management. The focus of my dissertation is to improve the applicability of terrestrial gross and net primary productivity (GPP/NPP) datasets for the conterminous United States (CONUS). In chapter one, I develop a framework for creating high resolution datasets of vegetation dynamics. I use the entire archive of Landsat 5, 7, and 8 surface reflectance data and a novel gap filling approach to create spatially continuous 30 m, 16-day composites of the normalized difference vegetation index (NDVI) from 1986 to 2016. In chapter two, I integrate this with other high resolution datasets and the MOD17 algorithm to create the first high resolution GPP and NPP datasets for CONUS. I demonstrate the applicability of these products for conservation and management, showing the improvements beyond currently available products. In chapter three, I utilize this dataset to evaluate the relationships between land ownership and terrestrial production

  19. A new simple and cheap, high-resolution planar optode imaging system: Application to oxgen and pH sensing

    DEFF Research Database (Denmark)

    Larsen, Morten; Borisov, Sergey M.; Gunwald, Björn

    2011-01-01

    A simple, high resolution colormetric planar optode imaging approach is presented. The approach is simple and inexpensive yet versatile, and can be used to study the two-dimensional distribution and dynamics of a range of analytes. The imaging approach utilizes the inbuilt color filter of standard...... commercial digital single lens reflex cameras to simultaneously record different colors (red, green, and blue) of luminophore emission light using only one excitation light source. Using the ratio between the intensity of the different colors recorded in a single image analyte concentrations can...... be calculated. The robustness of the approach is documented by obtaining high resolution data of O2 and pH distributions in marine sediments using easy synthesizable sensors. The sensors rely on the platinum(II)octaethylporphyrin (PtOEP) and lipophilic 8-Hydroxy-1,3,6-pyrenetrisulfonic acid trisodium (HPTS...

  20. A simple and inexpensive high resolution color ratiometric planar optode imaging approach: application to oxygen and pH sensing

    DEFF Research Database (Denmark)

    Larsen, M.; Borisov, S. M.; Grunwald, B.

    2011-01-01

    A simple, high resolution colormetric planar optode imaging approach is presented. The approach is simple and inexpensive yet versatile, and can be used to study the two-dimensional distribution and dynamics of a range of analytes. The imaging approach utilizes the inbuilt color filter of standard...... commercial digital single lens reflex cameras to simultaneously record different colors (red, green, and blue) of luminophore emission light using only one excitation light source. Using the ratio between the intensity of the different colors recorded in a single image analyte concentrations can...... be calculated. The robustness of the approach is documented by obtaining high resolution data of O-2 and pH distributions in marine sediments using easy synthesizable sensors. The sensors rely on the platinum(II) octaethylporphyrin (PtOEP) and lipophilic 8-Hydroxy-1,3,6-pyrenetrisulfonic acid trisodium (HPTS...

  1. A new high-resolution electromagnetic method for subsurface imaging

    Science.gov (United States)

    Feng, Wanjie

    For most electromagnetic (EM) geophysical systems, the contamination of primary fields on secondary fields ultimately limits the capability of the controlled-source EM methods. Null coupling techniques were proposed to solve this problem. However, the small orientation errors in the null coupling systems greatly restrict the applications of these systems. Another problem encountered by most EM systems is the surface interference and geologic noise, which sometimes make the geophysical survey impossible to carry out. In order to solve these problems, the alternating target antenna coupling (ATAC) method was introduced, which greatly removed the influence of the primary field and reduced the surface interference. But this system has limitations on the maximum transmitter moment that can be used. The differential target antenna coupling (DTAC) method was proposed to allow much larger transmitter moments and at the same time maintain the advantages of the ATAC method. In this dissertation, first, the theoretical DTAC calculations were derived mathematically using Born and Wolf's complex magnetic vector. 1D layered and 2D blocked earth models were used to demonstrate that the DTAC method has no responses for 1D and 2D structures. Analytical studies of the plate model influenced by conductive and resistive backgrounds were presented to explain the physical phenomenology behind the DTAC method, which is the magnetic fields of the subsurface targets are required to be frequency dependent. Then, the advantages of the DTAC method, e.g., high-resolution, reducing the geologic noise and insensitive to surface interference, were analyzed using surface and subsurface numerical examples in the EMGIMA software. Next, the theoretical advantages, such as high resolution and insensitive to surface interference, were verified by designing and developing a low-power (moment of 50 Am 2) vertical-array DTAC system and testing it on controlled targets and scaled target coils. At last, a

  2. High resolution multi-scalar drought indices for Iberia

    Science.gov (United States)

    Russo, Ana; Gouveia, Célia; Trigo, Ricardo; Jerez, Sonia

    2014-05-01

    The Iberian Peninsula has been recurrently affected by drought episodes and by adverse associated effects (Gouveia et al., 2009), ranging from severe water shortages to losses of hydroelectricity production, increasing risk of forest fires, forest decline and triggering processes of land degradation and desertification. Moreover, Iberia corresponds to one of the most sensitive areas to current and future climate change and is nowadays considered a hot spot of climate change with high probability for the increase of extreme events (Giorgi and Lionello, 2008). The spatial and temporal behavior of climatic droughts at different time scales was analyzed using spatially distributed time series of multi-scalar drought indicators, such as the Standardized Precipitation Evapotranspiration Index (SPEI) (Vicente-Serrano et al., 2010). This new climatic drought index is based on the simultaneous use of precipitation and temperature fields with the advantage of combining a multi-scalar character with the capacity to include the effects of temperature variability on drought assessment. Moreover, reanalysis data and the higher resolution hindcasted databases obtained from them are valuable surrogates of the sparse observations and widely used for in-depth characterizations of the present-day climate. Accordingly, this work aims to enhance the knowledge on high resolution drought patterns in Iberian Peninsula, taking advantage of high-resolution (10km) regional MM5 simulations of the recent past (1959-2007) over Iberia. It should be stressed that these high resolution meteorological fields (e.g. temperature, precipitation) have been validated for various purposes (Jerez et al., 2013). A detailed characterization of droughts since the 1960s using the 10 km resolution hidncasted simulation was performed with the aim to explore the conditions favoring drought onset, duration and ending, as well as the subsequent short, medium and long-term impacts affecting the environment and the

  3. HCN Polymers: Toward Structure Comprehension Using High Resolution Mass Spectrometry

    Science.gov (United States)

    Bonnet, Jean-Yves; Thissen, Roland; Frisari, Ma; Vuitton, Veronique; Quirico, Eric; Le Roy, Léna; Fray, Nicolas; Cottin, Hervé; Horst, Sarah; Yelle, Roger

    A lot of solar system materials, including cometary ices and Titan aerosols, contain dark matter that can be interpreted as complex nitrogen bearing organic matter [1]. In laboratory experi-ments, HCN polymers are thus analogs of great interest. In fact they may be present in Titan atmosphere and in comet nuclei and then reprocessed as a CN distributed source [2], when ices began to sublimate and ejects from the nucleus organic matter grains [3]. The presence of HCN polymers is suggested because HCN molecule has been directly observed in 1P/Halley comet [4] and others. HCN polymers are also of prebiotic interest [5] as it can form amino acid under hydrolysis conditions. Even if they have been studied during the last decades, their chemical composition and structure are still poorly understood, and a great analytical effort has to be continued. In this way we present a high resolution mass spectrometry (HRMS) and a high resolution tandem mass spectrometry (MS/HRMS) analysis of HCN polymers. It was shown [6] that this is a suitable technique to elucidate composition and structure of the soluble part of tholins analogs of Titan's atmosphere aerosols. HCN polymers have never been studied by HRMS, thus we used a LTQ-Orbitrap XL high resolution mass spectrometer to analyse the HCN polymers. These are produced at LISA by direct polymerisation of pure liquid HCN, catalyzed by ammonia. HCN polymers have been completely dissolved in methanol and then injected in the mass spectrometer by ElectroSpray Ionization (ESI). This atmospheric pressure ionization process produces protonated or deprotonated ions, but it does not fragment molecules. Thus HRMS, allows a direct access to the stoechiometry of all the ionizable molecules present in the samples. Fragmentation analyses (MS/MS) of selected ions have also been performed. Thess analysis provide information about the different chemical fonctionnalities present in HCN poly-mers and also about their structure. Thus we are able to

  4. Bayesian reconstruction of photon interaction sequences for high-resolution PET detectors

    Energy Technology Data Exchange (ETDEWEB)

    Pratx, Guillem; Levin, Craig S [Molecular Imaging Program at Stanford, Department of Radiology, Stanford, CA (United States)], E-mail: cslevin@stanford.edu

    2009-09-07

    Realizing the full potential of high-resolution positron emission tomography (PET) systems involves accurately positioning events in which the annihilation photon deposits all its energy across multiple detector elements. Reconstructing the complete sequence of interactions of each photon provides a reliable way to select the earliest interaction because it ensures that all the interactions are consistent with one another. Bayesian estimation forms a natural framework to maximize the consistency of the sequence with the measurements while taking into account the physics of {gamma}-ray transport. An inherently statistical method, it accounts for the uncertainty in the measured energy and position of each interaction. An algorithm based on maximum a posteriori (MAP) was evaluated for computer simulations. For a high-resolution PET system based on cadmium zinc telluride detectors, 93.8% of the recorded coincidences involved at least one photon multiple-interactions event (PMIE). The MAP estimate of the first interaction was accurate for 85.2% of the single photons. This represents a two-fold reduction in the number of mispositioned events compared to minimum pair distance, a simpler yet efficient positioning method. The point-spread function of the system presented lower tails and higher peak value when MAP was used. This translated into improved image quality, which we quantified by studying contrast and spatial resolution gains.

  5. Successful "First Light" for VLT High-Resolution Spectrograph

    Science.gov (United States)

    1999-10-01

    Great Research Prospects with UVES at KUEYEN A major new astronomical instrument for the ESO Very Large Telescope at Paranal (Chile), the UVES high-resolution spectrograph, has just made its first observations of astronomical objects. The astronomers are delighted with the quality of the spectra obtained at this moment of "First Light". Although much fine-tuning still has to be done, this early success promises well for new and exciting science projects with this large European research facility. Astronomical instruments at VLT KUEYEN The second VLT 8.2-m Unit Telescope, KUEYEN ("The Moon" in the Mapuche language), is in the process of being tuned to perfection before it will be "handed" over to the astronomers on April 1, 2000. The testing of the new giant telescope has been successfully completed. The latest pointing tests were very positive and, from real performance measurements covering the entire operating range of the telescope, the overall accuracy on the sky was found to be 0.85 arcsec (the RMS-value). This is an excellent result for any telescope and implies that KUEYEN (as is already the case for ANTU) will be able to acquire its future target objects securely and efficiently, thus saving precious observing time. This work has paved the way for the installation of large astronomical instruments at its three focal positions, all prototype facilities that are capable of catching the light from even very faint and distant celestial objects. The three instruments at KUEYEN are referred to by their acronyms UVES , FORS2 and FLAMES. They are all dedicated to the investigation of the spectroscopic properties of faint stars and galaxies in the Universe. The UVES instrument The first to be installed is the Ultraviolet Visual Echelle Spectrograph (UVES) that was built by ESO, with the collaboration of the Trieste Observatory (Italy) for the control software. Complete tests of its optical and mechanical components, as well as of its CCD detectors and of the complex

  6. A novel intra-operative, high-resolution atrial mapping approach.

    Science.gov (United States)

    Yaksh, Ameeta; van der Does, Lisette J M E; Kik, Charles; Knops, Paul; Oei, Frans B S; van de Woestijne, Pieter C; Bekkers, Jos A; Bogers, Ad J J C; Allessie, Maurits A; de Groot, Natasja M S

    2015-12-01

    A new technique is demonstrated for extensive high-resolution intra-operative atrial mapping that will facilitate the localization of atrial fibrillation (AF) sources and identification of the substrate perpetuating AF. Prior to the start of extra-corporal circulation, a 8 × 24-electrode array (2-mm inter-electrode distance) is placed subsequently on all the right and left epicardial atrial sites, including Bachmann's bundle, for recording of unipolar electrograms during sinus rhythm and (induced) AF. AF is induced by high-frequency pacing at the right atrial free wall. A pacemaker wire stitched to the right atrium serves as a reference signal. The indifferent pole is connected to a steal wire fixed to subcutaneous tissue. Electrograms are recorded by a computerized mapping system and, after amplification (gain 1000), filtering (bandwidth 0.5-400 Hz), sampling (1 kHz) and analogue to digital conversion (16 bits), automatically stored on hard disk. During the mapping procedure, real-time visualization secures electrogram quality. Analysis will be performed offline. This technique was performed in 168 patients of 18 years and older, with coronary and/or structural heart disease, with or without AF, electively scheduled for cardiac surgery and a ventricular ejection fraction above 40 %. The mean duration of the entire mapping procedure including preparation time was 9 ± 2 min. Complications related to the mapping procedure during or after cardiac surgery were not observed. We introduce the first epicardial atrial mapping approach with a high resolution of ≥1728 recording sites which can be performed in a procedure time of only 9±2 mins. This mapping technique can potentially identify areas responsible for initiation and persistence of AF and hopefully can individualize both diagnosis and therapy of AF.

  7. Southern Ocean Circulation: a High Resolution Examination of the Last Deglaciation from Deep-Sea Corals

    Science.gov (United States)

    Robinson, L. F.; Li, T.; Chen, T.; Burke, A.; Pegrum Haram, A.; Stewart, J.; Rae, J. W. B.; van de Flierdt, T.; Struve, T.; Wilson, D. J.

    2017-12-01

    Two decades ago it was first noted that the skeletal remains of deep-sea corals had the potential to provide absolutely dated archives of past ocean conditions. In the intervening twenty years this field has developed to the point where strategic collections and high throughput dating techniques now allow high resolution, well dated records of past deep sea behaviour to be produced. Likewise, efforts to improve understanding of biomineralisation and growth rates are leading to refinements in proxy tools useful for examining circulation, nutrient and carbon cycling, temperature and weathering processes. Deep-sea corals are particularly valuable archives in high latitude regions where radiocarbon-based age models are susceptible to large changes in surface reservoir ages. In this presentation we show new high resolution multiproxy records of the Southern Ocean (Drake Passage) made on U-Th dated corals spanning the last glacial cycle. With more than seventeen hundred reconnaissance ages, and around 200 precise isotope dilution U-Th ages, subtle changes in ocean behaviour can be identified during times of abrupt climate change. The geochemical signature of corals from the deepest sites, closest to modern day Lower Circumpolar Deep Waters, typically show a gradual shift from glacial to Holocene values during deglaciation, likely related to ventilation of the deep ocean. By contrast for the samples collected shallower in the water column (within sites currently bathed by Upper Circumpolar Deep Waters and Antarctic Intermediate and Mode Waters) the evidence points to a more complicated picture. Vertical zonation in the geochemical data suggests that periods of stratification are interspersed with mixing events within the upper 1500m of the water column. At the same time comparison to U-Th dated records from the low latitude Pacific and Atlantic points to an important role for the Southern Ocean in feeding the intermediate waters of both ocean basins throughout the

  8. High-resolution global irradiance monitoring from photovoltaic systems

    Science.gov (United States)

    Buchmann, Tina; Pfeilsticker, Klaus; Siegmund, Alexander; Meilinger, Stefanie; Mayer, Bernhard; Pinitz, Sven; Steinbrecht, Wolfgang

    2016-04-01

    Reliable and regional differentiated power forecasts are required to guarantee an efficient and economic energy transition towards renewable energies. Amongst other renewable energy technologies, e.g. wind mills, photovoltaic systems are an essential component of this transition being cost-efficient and simply to install. Reliable power forecasts are however required for a grid integration of photovoltaic systems, which among other data requires high-resolution spatio-temporal global irradiance data. Hence the generation of robust reviewed global irradiance data is an essential contribution for the energy transition. To achieve this goal our studies introduce a novel method which makes use of photovoltaic power generation in order to infer global irradiance. The method allows to determine high-resolution temporal global irradiance data (one data point every 15 minutes at each location) from power data of operated photovoltaic systems. Due to the multitude of installed photovoltaic systems (in Germany) the detailed spatial coverage is much better than for example only using global irradiance data from conventional pyranometer networks (e.g. from the German Weather Service). Our designated method is composed of two components: a forward component, i.e. to conclude from predicted global irradiance to photovoltaic (PV) power, and a backward component, i.e. from PV power with suitable calibration to global irradiance. The forward process is modelled by using the radiation transport model libRadtran (B. Mayer and A. Kylling (1)) for clear skies to obtain the characteristics (orientation, size, temperature dependence, …) of individual PV systems. For PV systems in the vicinity of a meteorological station, these data are validated against calibrated pyranometer readings. The forward-modelled global irradiance is used to determine the power efficiency for each photovoltaic system using non-linear optimisation techniques. The backward component uses the power efficiency

  9. Precision cosmology with time delay lenses: high resolution imaging requirements

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Xiao-Lei; Liao, Kai [Department of Astronomy, Beijing Normal University, 19 Xinjiekouwai Street, Beijing, 100875 (China); Treu, Tommaso; Agnello, Adriano [Department of Physics, University of California, Broida Hall, Santa Barbara, CA 93106 (United States); Auger, Matthew W. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Marshall, Philip J., E-mail: xlmeng919@gmail.com, E-mail: tt@astro.ucla.edu, E-mail: aagnello@physics.ucsb.edu, E-mail: mauger@ast.cam.ac.uk, E-mail: liaokai@mail.bnu.edu.cn, E-mail: dr.phil.marshall@gmail.com [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, 452 Lomita Mall, Stanford, CA 94305 (United States)

    2015-09-01

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ''Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρ{sub tot}∝ r{sup −γ'} for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. However, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation

  10. Global High Resolution Sea Surface Flux Parameters From Multiple Satellites

    Science.gov (United States)

    Zhang, H.; Reynolds, R. W.; Shi, L.; Bates, J. J.

    2007-05-01

    Advances in understanding the coupled air-sea system and modeling of the ocean and atmosphere demand increasingly higher resolution data, such as air-sea fluxes of up to 3 hourly and every 50 km. These observational requirements can only be met by utilizing multiple satellite observations. Generation of such high resolution products from multiple-satellite and in-situ observations on an operational basis has been started at the U.S. National Oceanic and Atmospheric Administration (NOAA) National Climatic Data Center. Here we describe a few products that are directly related to the computation of turbulent air-sea fluxes. Sea surface wind speed has been observed from in-situ instruments and multiple satellites, with long-term observations ranging from one satellite in the mid 1987 to six or more satellites since mid 2002. A blended product with a global 0.25° grid and four snapshots per day has been produced for July 1987 to present, using a near Gaussian 3-D (x, y, t) interpolation to minimize aliases. Wind direction has been observed from fewer satellites, thus for the blended high resolution vector winds and wind stresses, the directions are taken from the NCEP Re-analysis 2 (operationally run near real time) for climate consistency. The widely used Reynolds Optimum Interpolation SST analysis has been improved with higher resolutions (daily and 0.25°). The improvements use both infrared and microwave satellite data that are bias-corrected by in- situ observations for the period 1985 to present. The new versions provide very significant improvements in terms of resolving ocean features such as the meandering of the Gulf Stream, the Aghulas Current, the equatorial jets and other fronts. The Ta and Qa retrievals are based on measurements from the AMSU sounder onboard the NOAA satellites. Ta retrieval uses AMSU-A data, while Qa retrieval uses both AMSU-A and AMSU-B observations. The retrieval algorithms are developed using the neural network approach. Training

  11. Spatial Ensemble Postprocessing of Precipitation Forecasts Using High Resolution Analyses

    Science.gov (United States)

    Lang, Moritz N.; Schicker, Irene; Kann, Alexander; Wang, Yong

    2017-04-01

    Ensemble prediction systems are designed to account for errors or uncertainties in the initial and boundary conditions, imperfect parameterizations, etc. However, due to sampling errors and underestimation of the model errors, these ensemble forecasts tend to be underdispersive, and to lack both reliability and sharpness. To overcome such limitations, statistical postprocessing methods are commonly applied to these forecasts. In this study, a full-distributional spatial post-processing method is applied to short-range precipitation forecasts over Austria using Standardized Anomaly Model Output Statistics (SAMOS). Following Stauffer et al. (2016), observation and forecast fields are transformed into standardized anomalies by subtracting a site-specific climatological mean and dividing by the climatological standard deviation. Due to the need of fitting only a single regression model for the whole domain, the SAMOS framework provides a computationally inexpensive method to create operationally calibrated probabilistic forecasts for any arbitrary location or for all grid points in the domain simultaneously. Taking advantage of the INCA system (Integrated Nowcasting through Comprehensive Analysis), high resolution analyses are used for the computation of the observed climatology and for model training. The INCA system operationally combines station measurements and remote sensing data into real-time objective analysis fields at 1 km-horizontal resolution and 1 h-temporal resolution. The precipitation forecast used in this study is obtained from a limited area model ensemble prediction system also operated by ZAMG. The so called ALADIN-LAEF provides, by applying a multi-physics approach, a 17-member forecast at a horizontal resolution of 10.9 km and a temporal resolution of 1 hour. The performed SAMOS approach statistically combines the in-house developed high resolution analysis and ensemble prediction system. The station-based validation of 6 hour precipitation sums

  12. Managing the explosion of high resolution topography in the geosciences

    Science.gov (United States)

    Crosby, Christopher; Nandigam, Viswanath; Arrowsmith, Ramon; Phan, Minh; Gross, Benjamin

    2017-04-01

    Centimeter to decimeter-scale 2.5 to 3D sampling of the Earth surface topography coupled with the potential for photorealistic coloring of point clouds and texture mapping of meshes enables a wide range of science applications. Not only is the configuration and state of the surface as imaged valuable, but repeat surveys enable quantification of topographic change (erosion, deposition, and displacement) caused by various geologic processes. We are in an era of ubiquitous point clouds that come from both active sources such as laser scanners and radar as well as passive scene reconstruction via structure from motion (SfM) photogrammetry. With the decreasing costs of high-resolution topography (HRT) data collection, via methods such as SfM and UAS-based laser scanning, the number of researchers collecting these data is increasing. These "long-tail" topographic data are of modest size but great value, and challenges exist to making them widely discoverable, shared, annotated, cited, managed and archived. Presently, there are no central repositories or services to support storage and curation of these datasets. The U.S. National Science Foundation funded OpenTopography (OT) Facility employs cyberinfrastructure including large-scale data management, high-performance computing, and service-oriented architectures, to provide efficient online access to large HRT (mostly lidar) datasets, metadata, and processing tools. With over 225 datasets and 15,000 registered users, OT is well positioned to provide curation for community collected high-resolution topographic data. OT has developed a "Community DataSpace", a service built on a low cost storage cloud (e.g. AWS S3) to make it easy for researchers to upload, curate, annotate and distribute their datasets. The system's ingestion workflow will extract metadata from data uploaded; validate it; assign a digital object identifier (DOI); and create a searchable catalog entry, before publishing via the OT portal. The OT Community

  13. Immersion Gratings for Infrared High-resolution Spectroscopy

    Science.gov (United States)

    Sarugaku, Yuki; Ikeda, Yuji; Kobayashi, Naoto; Kaji, Sayumi; Sukegawa, Takashi; Sugiyama, Shigeru; Nakagawa, Takao; Arasaki, Takayuki; Kondo, Sohei; Nakanishi, Kenshi; Yasui, Chikako; Kawakita, Hideyo

    2016-10-01

    High-resolution spectroscopy in the infrared wavelength range is essential for observations of minor isotopologues, such as HDO for water, and prebiotic organic molecules like hydrocarbons/P-bearing molecules because numerous vibrational molecular bands (including non-polar molecules) are located in this wavelength range. High spectral resolution enables us to detect weak lines without spectral line confusion. This technique has been widely used in planetary sciences, e.g., cometary coma (H2O, CO, and organic molecules), the martian atmosphere (CH4, CO2, H2O and HDO), and the upper atmosphere of gas giants (H3+ and organic molecules such as C2H6). Spectrographs with higher resolution (and higher sensitivity) still have a potential to provide a plenty of findings. However, because the size of spectrographs scales with the spectral resolution, it is difficult to realize it.Immersion grating (IG), which is a diffraction grating wherein the diffraction surface is immersed in a material with a high refractive index (n > 2), provides n times higher spectral resolution compared to a reflective grating of the same size. Because IG reduces the size of spectrograph to 1/n compared to the spectrograph with the same spectral resolution using a conventional reflective grating, it is widely acknowledged as a key optical device to realize compact spectrographs with high spectral resolution.Recently, we succeeded in fabricating a CdZnTe immersion grating with the theoretically predicted diffraction efficiency by machining process using an ultrahigh-precision five-axis processing machine developed by Canon Inc. Using the same technique, we completed a practical germanium (Ge) immersion grating with both a reflection coating on the grating surface and the an AR coating on the entrance surface. It is noteworthy that the wide wavelength range from 2 to 20 um can be covered by the two immersion gratings.In this paper, we present the performances and the applications of the immersion

  14. ASIC-enabled High Resolution Optical Time Domain Reflectometer

    Science.gov (United States)

    Skendzic, Sandra

    Fiber optics has become the preferred technology in communication systems because of what it has to offer: high data transmission rates, immunity to electromagnetic interference, and lightweight, flexible cables. An optical time domain reflectometer (OTDR) provides a convenient method of locating and diagnosing faults (e.g. break in a fiber) along a fiber that can obstruct crucial optical pathways. Both the ability to resolve the precise location of the fault and distinguish between two discrete, closely spaced faults are figures of merit. This thesis presents an implementation of a high resolution OTDR through the use of a compact and programmable ASIC (application specific integrated circuit). The integration of many essential OTDR functions on a single chip is advantageous over existing commercial instruments because it enables small, lightweight packaging, and offers low power and cost efficiency. Furthermore, its compactness presents the option of placing multiple ASICs in parallel, which can conceivably ease the characterization of densely populated fiber optic networks. The OTDR ASIC consists of a tunable clock, pattern generator, precise timer, electrical receiver, and signal sampling circuit. During OTDR operation, the chip generates narrow electrical pulse, which can then be converted to optical format when coupled with an external laser diode driver. The ASIC also works with an external photodetector to measure the timing and amplitude of optical reflections in a fiber. It has a 1 cm sampling resolution, which allows for a 2 cm spatial resolution. While this OTDR ASIC has been previously demonstrated for multimode fiber fault diagnostics, this thesis focuses on extending its functionality to single mode fiber. To validate this novel approach to OTDR, this thesis is divided into five chapters: (1) introduction, (2) implementation, (3), performance of ASIC-based OTDR, (4) exploration in optical pre-amplification with a semiconductor optical amplifier, and

  15. High Resolution Hurricane Storm Surge and Inundation Modeling (Invited)

    Science.gov (United States)

    Luettich, R.; Westerink, J. J.

    2010-12-01

    Coastal counties are home to nearly 60% of the U.S. population and industry that accounts for over 16 million jobs and 10% of the U.S. annual gross domestic product. However, these areas are susceptible to some of the most destructive forces in nature, including tsunamis, floods, and severe storm-related hazards. Since 1900, tropical cyclones making landfall on the US Gulf of Mexico Coast have caused more than 9,000 deaths; nearly 2,000 deaths have occurred during the past half century. Tropical cyclone-related adjusted, annualized losses in the US have risen from 1.3 billion from 1949-1989, to 10.1 billion from 1990-1995, and $35.8 billion per year for the period 2001-2005. The risk associated with living and doing business in the coastal areas that are most susceptible to tropical cyclones is exacerbated by rising sea level and changes in the characteristics of severe storms associated with global climate change. In the five years since hurricane Katrina devastated the northern Gulf of Mexico Coast, considerable progress has been made in the development and utilization of high resolution coupled storm surge and wave models. Recent progress will be presented with the ADCIRC + SWAN storm surge and wave models. These tightly coupled models use a common unstructured grid in the horizontal that is capable of covering large areas while also providing high resolution (i.e., base resolution down to 20m plus smaller subgrid scale features such as sea walls and levees) in areas that are subject to surge and inundation. Hydrodynamic friction and overland winds are adjusted to account for local land cover. The models scale extremely well on modern high performance computers allowing rapid turnaround on large numbers of compute cores. The models have been adopted for FEMA National Flood Insurance Program studies, hurricane protection system design and risk analysis, and quasi-operational forecast systems for several regions of the country. They are also being evaluated as

  16. High Resolution Digital Elevation Models of Pristine Explosion Craters

    Science.gov (United States)

    Farr, T. G.; Krabill, W.; Garvin, J. B.

    2004-01-01

    In order to effectively capture a realistic terrain applicable to studies of cratering processes and landing hazards on Mars, we have obtained high resolution digital elevation models of several pristine explosion craters at the Nevada Test Site. We used the Airborne Terrain Mapper (ATM), operated by NASA's Wallops Flight Facility to obtain DEMs with 1 m spacing and 10 cm vertical errors of 4 main craters and many other craters and collapse pits. The main craters that were mapped are Sedan, Scooter, Schooner, and Danny Boy. The 370 m diameter Sedan crater, located on Yucca Flat, is the largest and freshest explosion crater on Earth that was formed under conditions similar to hypervelocity impact cratering. As such, it is effectively pristine, having been formed in 1962 as a result of a controlled detonation of a 100 kiloton thermonuclear device, buried at the appropriate equivalent depth of burst required to make a simple crater. Sedan was formed in alluvium of mixed lithology and subsequently studied using a variety of field-based methods. Nearby secondary craters were also formed at the time and were also mapped by ATM. Adjacent to Sedan and also in alluvium is Scooter, about 90 m in diameter and formed by a high-explosive event. Schooner (240 m) and Danny Boy (80 m) craters were also important targets for ATM as they were excavated in hard basalt and therefore have much rougher ejecta. This will allow study of ejecta patterns in hard rock as well as engineering tests of crater and rock avoidance and rover trafficability. In addition to the high resolution DEMs, crater geometric characteristics, RMS roughness maps, and other higher-order derived data products will be generated using these data. These will provide constraints for models of landing hazards on Mars and for rover trafficability. Other planned studies will include ejecta size-frequency distribution at the resolution of the DEM and at finer resolution through air photography and field measurements

  17. High-resolution metabolomics of occupational exposure to trichloroethylene.

    Science.gov (United States)

    Walker, Douglas I; Uppal, Karan; Zhang, Luoping; Vermeulen, Roel; Smith, Martyn; Hu, Wei; Purdue, Mark P; Tang, Xiaojiang; Reiss, Boris; Kim, Sungkyoon; Li, Laiyu; Huang, Hanlin; Pennell, Kurt D; Jones, Dean P; Rothman, Nathaniel; Lan, Qing

    2016-10-01

    Occupational exposure to trichloroethylene (TCE) has been linked to adverse health outcomes including non-Hodgkin's lymphoma and kidney and liver cancer; however, TCE's mode of action for development of these diseases in humans is not well understood. Non-targeted metabolomics analysis of plasma obtained from 80 TCE-exposed workers [full shift exposure range of 0.4 to 230 parts-per-million of air (ppm a )] and 95 matched controls were completed by ultra-high resolution mass spectrometry. Biological response to TCE exposure was determined using a metabolome-wide association study (MWAS) framework, with metabolic changes and plasma TCE metabolites evaluated by dose-response and pathway enrichment. Biological perturbations were then linked to immunological, renal and exposure molecular markers measured in the same population. Metabolic features associated with TCE exposure included known TCE metabolites, unidentifiable chlorinated compounds and endogenous metabolites. Exposure resulted in a systemic response in endogenous metabolism, including disruption in purine catabolism and decreases in sulphur amino acid and bile acid biosynthesis pathways. Metabolite associations with TCE exposure included uric acid (β = 0.13, P-value = 3.6 × 10 -5 ), glutamine (β = 0.08, P-value = 0.0013), cystine (β = 0.75, P-value = 0.0022), methylthioadenosine (β = -1.6, P-value = 0.0043), taurine (β = -2.4, P-value = 0.0011) and chenodeoxycholic acid (β = -1.3, P-value = 0.0039), which are consistent with known toxic effects of TCE, including immunosuppression, hepatotoxicity and nephrotoxicity. Correlation with additional exposure markers and physiological endpoints supported known disease associations. High-resolution metabolomics correlates measured occupational exposure to internal dose and metabolic response, providing insight into molecular mechanisms of exposure-related disease aetiology. © The Author 2016; all rights

  18. The high resolution mapping of the Venice Lagoon tidal network

    Science.gov (United States)

    Madricardo, Fantina; Foglini, Federica; Kruss, Aleksandra; Bellafiore, Debora; Trincardi, Fabio

    2017-04-01

    One of the biggest challenges of the direct observation of the ocean is to achieve a high resolution mapping of its seafloor morphology and benthic habitats. So far, sonars have mapped just 0.05% of the ocean floor with less than ten-meter resolution. The recent efforts of the scientific community have been devoted towards the mapping of both Deep Ocean and very shallow coastal areas. Coastal and transitional environments in particular undergo strong morphological changes due to natural and anthropogenic pressure. Nowadays, only about 5% of the seafloor of these environments † have been mapped: the shallowness of these environments has prevented the use of underwater acoustics to reveal their morphological features. The recent technological development of multibeam echosounder systems, however, enables these instruments to achieve very high performances also in such shallow environments. In this work, we present results and case studies of an extensive multibeam survey carried out in the Lagoon of Venice in 2013. The Lagoon of Venice is the biggest lagoon in the Mediterranean Sea with a surface of about 550 km2 and with an average depth of about 1 m. In the last century, the morphological and ecological properties of the lagoon changed dramatically: the surface of the salt marshes was reduced by 60% and some parts of the lagoon are deepening with a net sediment flux exiting from the inlets. Moreover, major engineering interventions are currently ongoing at the inlets (MOSE project). These changes at the inlets could affect substantially the lagoon environment. To understand and monitor the future evolution of the Lagoon of Venice, ISMAR within the project RITMARE (a National Research Programme funded by the Italian Ministry of University and Research) carried out an extensive survey, involving a team of more than 25 scientists, to collect high resolution (0.5 m) bathymetry of key study areas such as the tidal inlets and channels. Following a broad

  19. High Resolution Reconstruction of the Ionosphere for SAR Applications

    Science.gov (United States)

    Minkwitz, David; Gerzen, Tatjana; Hoque, Mainul

    2014-05-01

    Caused by ionosphere's strong impact on radio signal propagation, high resolution and highly accurate reconstructions of the ionosphere's electron density distribution are demanded for a large number of applications, e.g. to contribute to the mitigation of ionospheric effects on Synthetic Aperture Radar (SAR) measurements. As a new generation of remote sensing satellites the TanDEM-L radar mission is planned to improve the understanding and modelling ability of global environmental processes and ecosystem change. TanDEM-L will operate in L-band with a wavelength of approximately 24 cm enabling a stronger penetration capability compared to X-band (3 cm) or C-band (5 cm). But accompanied by the lower frequency of the TanDEM-L signals the influence of the ionosphere will increase. In particular small scale irregularities of the ionosphere might lead to electron density variations within the synthetic aperture length of the TanDEM-L satellite and in turn might result into blurring and azimuth pixel shifts. Hence the quality of the radar image worsens if the ionospheric effects are not mitigated. The Helmholtz Alliance project "Remote Sensing and Earth System Dynamics" (EDA) aims in the preparation of the HGF centres and the science community for the utilisation and integration of the TanDEM-L products into the study of the Earth's system. One significant point thereby is to cope with the mentioned ionospheric effects. Therefore different strategies towards achieving this objective are pursued: the mitigation of the ionospheric effects based on the radar data itself, the mitigation based on external information like global Total Electron Content (TEC) maps or reconstructions of the ionosphere and the combination of external information and radar data. In this presentation we describe the geostatistical approach chosen to analyse the behaviour of the ionosphere and to provide a high resolution 3D electron density reconstruction. As first step the horizontal structure of

  20. Precision cosmology with time delay lenses: High resolution imaging requirements

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Xiao -Lei [Beijing Normal Univ., Beijing (China); Univ. of California, Santa Barbara, CA (United States); Treu, Tommaso [Univ. of California, Santa Barbara, CA (United States); Univ. of California, Los Angeles, CA (United States); Agnello, Adriano [Univ. of California, Santa Barbara, CA (United States); Univ. of California, Los Angeles, CA (United States); Auger, Matthew W. [Univ. of Cambridge, Cambridge (United Kingdom); Liao, Kai [Beijing Normal Univ., Beijing (China); Univ. of California, Santa Barbara, CA (United States); Univ. of California, Los Angeles, CA (United States); Marshall, Philip J. [Stanford Univ., Stanford, CA (United States)

    2015-09-28

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ``Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρtot∝ r–γ' for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. Furthermore, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation Adaptive