Relevant bibliographies by topics / Contrast sensitivity

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Contrast sensitivity'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 August 2024

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Journal articles on the topic "Contrast sensitivity"

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Wallace, Mark T. "Contrast Sensitivity." Journal of Cognitive Neuroscience 7, no. 3 (July 1995): 420–21. http://dx.doi.org/10.1162/jocn.1995.7.3.420.

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Cibis, Gerhard W., and Max S. Mancillas. "Contrast sensitivity." Current Opinion in Ophthalmology 2, no. 1 (February 1991): 81–84. http://dx.doi.org/10.1097/00055735-199102000-00013.

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YATES, J. TERRY, JOSEPH M. HARRISON, PATRICK S. OʼCONNOR, and CHARLES BALLENTINE. "Contrast Sensitivity." Optometry and Vision Science 64, no. 7 (July 1987): 519–27. http://dx.doi.org/10.1097/00006324-198707000-00006.

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OWSLEY, C. "Contrast sensitivity." Ophthalmology Clinics of North America 16, no. 2 (June 2003): 171–77. http://dx.doi.org/10.1016/s0896-1549(03)00003-8.

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Bang, Seangbae, and Wonha Kim. "Image Enhancement Using The Contrast Sensitivity Function." Journal of Broadcast Engineering 20, no. 2 (March 30, 2015): 238–47. http://dx.doi.org/10.5909/jbe.2015.20.2.238.

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Pelli, Denis G., and Peter Bex. "Measuring contrast sensitivity." Vision Research 90 (September 2013): 10–14. http://dx.doi.org/10.1016/j.visres.2013.04.015.

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Bodis-Wollner, I. "Visual contrast sensitivity." Neurology 38, no. 2 (February 1, 1988): 336. http://dx.doi.org/10.1212/wnl.38.2.336.

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Lorance, R. W., D. Kaufman, and S. H. Wray. "Visual contrast sensitivity." Neurology 38, no. 2 (February 1, 1988): 336. http://dx.doi.org/10.1212/wnl.38.2.336-a.

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Rizzo, Martew. "Measuring contrast sensitivity." Annals of Neurology 20, no. 3 (September 1986): 374. http://dx.doi.org/10.1002/ana.410200322.

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Khambhiphant, Bharkbhum, Wasee Tulvatana, and Mathu Busayarat. "The new numbers contrast sensitivity chart for contrast sensitivity measurement." Journal of Optometry 4, no. 4 (October 2011): 128–33. http://dx.doi.org/10.1016/s1888-4296(11)70054-1.

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Dissertations / Theses on the topic "Contrast sensitivity"

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Ghim, Mimi M. "Spatial contrast sensitivity of birds." College Park, Md. : University of Maryland, 2003. http://hdl.handle.net/1903/65.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2003.
Thesis research directed by: Psychology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Olesko, Brian M. "Dynamic contrast sensitivity : methods and measurements /." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09052009-040416/.

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Barten, Peter G. J. "Contrast sensitivity of the human eye and its effects on image quality." Bellingham, Wash. (1000 20th St. Bellingham WA 98225-6705 USA) : SPIE, 1999. http://dx.doi.org/10.1117/3.353254.

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Thesis (doctoral)--Technische Universiteit Eindhoven, 1999.
"SPIE digital library." Originally published: Knegsel : HV Press, 1999. Includes bibliographical references and index. Also available in print version.
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Ukkonen, Outi I. "Contrast sensitivity for complex and random gratings." Thesis, Aston University, 1995. http://publications.aston.ac.uk/14610/.

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This thesis studied the effect of (i) the number of grating components and (ii) parameter randomisation on root-mean-square (r.m.s.) contrast sensitivity and spatial integration. The effectiveness of spatial integration without external spatial noise depended on the number of equally spaced orientation components in the sum of gratings. The critical area marking the saturation of spatial integration was found to decrease when the number of components increased from 1 to 5-6 but increased again at 8-16 components. The critical area behaved similarly as a function of the number of grating components when stimuli consisted of 3, 6 or 16 components with different orientations and/or phases embedded in spatial noise. Spatial integration seemed to depend on the global Fourier structure of the stimulus. Spatial integration was similar for sums of two vertical cosine or sine gratings with various Michelson contrasts in noise. The critical area for a grating sum was found to be a sum of logarithmic critical areas for the component gratings weighted by their relative Michelson contrasts. The human visual system was modelled as a simple image processor where the visual stimuli is first low-pass filtered by the optical modulation transfer function of the human eye and secondly high-pass filtered, up to the spatial cut-off frequency determined by the lowest neural sampling density, by the neural modulation transfer function of the visual pathways. The internal noise is then added before signal interpretation occurs in the brain. The detection is mediated by a local spatially windowed matched filter. The model was extended to include complex stimuli and its applicability to the data was found to be successful. The shape of spatial integration function was similar for non-randomised and randomised simple and complex gratings. However, orientation and/or phase randomised reduced r.m.s contrast sensitivity by a factor of 2.
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Drover, James R. "Modification of the infant contrast sensitivity card procedure." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ55503.pdf.

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Yap, M. K. H. "Clinical application of contrast sensitivity in visual dysfunction." Thesis, University of Bradford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371489.

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Tunnacliffe, A. H. "Contrast sensitivity as an indicator of binocular function." Thesis, University of Bradford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376693.

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Osman, Mawada. "Contrast Sensitivity and Visual Acuity among the Elderly." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1586874623985066.

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Mason, Alexandra J. S. "The contrast sensitivity of three groups of opthalmological patients." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336141.

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Grey, C. P. "Changes in contrast sensitivity during soft contact lens wear." Thesis, University of Bradford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376712.

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Books on the topic "Contrast sensitivity"

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M, Shapley R., and Lam Dominic Man-Kit, eds. Contrast sensitivity. Cambridge, Mass: MIT Press, 1993.

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Koskela, Pentti U. Contrast sensitivity in amblyopia. Oulu: University of Oulu, 1986.

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Nadler, M. Princeton, David Miller, and Daniel J. Nadler, eds. Glare and Contrast Sensitivity for Clinicians. New York, NY: Springer New York, 1990. http://dx.doi.org/10.1007/978-1-4612-3242-1.

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Princeton, Nadler M., Miller David 1931-, and Nadler Daniel J, eds. Glare and contrast sensitivity for clinicians. New York: Springer-Verlag, 1990.

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Ukkonen, Outi Irene. Contrast sensitivity for complex and random gratings. Birmingham: Aston University. Department of Vision Sciences, 1995.

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Leinonen, Markku. Taustan valaistus näkökenttätutkimuksessa =: Background luminance in visual field testing. Turku: Turun yliopisto, 1996.

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Griffiths, Stella Noelle. The effect of intraocular scattered light on the contrast sensitivity function. Birmingham: Aston University. Department of Vision Sciences, 1986.

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Perron, Adena Marie. The effect of vigabatrin treatment on contrast sensitivity in a pediatric population. Ottawa: National Library of Canada, 2001.

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Aldo, Badano, and National Institute of Standards and Technology (U.S.), eds. Characterization of luminance probe for accurate contrast measurements in medical displays. Gaithersburg, Md: U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, 2003.

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Klett, Zachary G. The correlation between objective lens opacity and laser interferometric contrast sensitivity in the cataract patient. [New Haven: s.n.], 1989.

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Book chapters on the topic "Contrast sensitivity"

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Klaproth, Oliver K. "Contrast Sensitivity." In Encyclopedia of Ophthalmology, 1–2. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-35951-4_378-4.

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Weale, R. A. "Contrast Sensitivity." In Low Vision, 45–55. New York, NY: Springer New York, 1987. http://dx.doi.org/10.1007/978-1-4612-4780-7_4.

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Skalicky, Simon E. "Contrast Sensitivity." In Ocular and Visual Physiology, 285–98. Singapore: Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-287-846-5_20.

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Klaproth, Oliver K. "Contrast Sensitivity." In Encyclopedia of Ophthalmology, 509–10. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-540-69000-9_378.

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Kupersmith, Mark J., Karen Holopigian, and William H. Seiple. "Contrast Sensitivity Testing." In New Methods of Sensory Visual Testing, 53–67. New York, NY: Springer New York, 1989. http://dx.doi.org/10.1007/978-1-4613-8835-7_4.

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Witzel, Christoph, and Karl Gegenfurtner. "Chromatic Contrast Sensitivity." In Encyclopedia of Color Science and Technology, 1–7. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-642-27851-8_17-1.

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Witzel, Christoph, and Karl Gegenfurtner. "Chromatic Contrast Sensitivity." In Encyclopedia of Color Science and Technology, 108–14. New York, NY: Springer New York, 2016. http://dx.doi.org/10.1007/978-1-4419-8071-7_17.

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Witzel, Christoph, and Karl Gegenfurtner. "Chromatic Contrast Sensitivity." In Encyclopedia of Color Science and Technology, 147–54. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-030-89862-5_17.

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Witzel, Christoph, and Karl Gegenfurtner. "Chromatic Contrast Sensitivity." In Encyclopedia of Color Science and Technology, 1–8. Berlin, Heidelberg: Springer Berlin Heidelberg, 2023. http://dx.doi.org/10.1007/978-3-642-27851-8_17-2.

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Bühren, Jens. "Contrast Sensitivity Function, General." In Encyclopedia of Ophthalmology, 1–3. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-642-35951-4_610-2.

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Conference papers on the topic "Contrast sensitivity"

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Kitaguchi, Saori, Lindsay MacDonald, and Stephen Westland. "Evaluating contrast sensitivity." In Electronic Imaging 2006, edited by Bernice E. Rogowitz, Thrasyvoulos N. Pappas, and Scott J. Daly. SPIE, 2006. http://dx.doi.org/10.1117/12.643188.

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Zeilikovich, Iosif S. "Holographic interferometry of phase objects with increasing sensitivity." In Phase Contrast and Differential Interference Contrast Imaging Techniques and Applications, edited by Maksymilian Pluta and Mariusz Szyjer. SPIE, 1994. http://dx.doi.org/10.1117/12.171865.

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Zaidi, Qasim. "Contrast sensitivity for input distributions." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/oam.1993.fhh.2.

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Visual models generally assume that the state of adaptation is set by the average incident light. These models successfully predict the empirical result that an observer adapted to a steady spatially uniform light has greatest sensitivity to contrasts around the adaptation point, and contrast sensitivity declines progressively as the radiance or chromaticity of the test light differs from that of the adaptation level.
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Majumder, Aditi, and Sandy Irani. "Contrast enhancement of images using human contrast sensitivity." In the 3rd symposium. New York, New York, USA: ACM Press, 2006. http://dx.doi.org/10.1145/1140491.1140506.

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Brown, Angela M. "Contrast sensitivity and contrast discrimination in human infants." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oam.1990.tus3.

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Poor contrast sensitivity is probably responsible for the poor color vision of infants. But, why is their contrast sensitivity poor? Is the deficit sensory, or is it due to perceptual and cognitive immaturities? Or, is it a methodological artifact?
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Mansouree, Mahdad, and Amir Arbabi. "Multi-layer multifunctional metasurface design using the adjoint sensitivity technique (Conference Presentation)." In High Contrast Metastructures VIII, edited by Connie J. Chang-Hasnain, Weimin Zhou, and Andrei Faraon. SPIE, 2019. http://dx.doi.org/10.1117/12.2510379.

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Cronin-Golomb, Alice, Suzanne Corkin, and John H. Growdon. "Contrast sensitivity In Alzheimer's disease." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/oam.1987.mc2.

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Studies on contrast sensitivity function (CSF) in Alzheimer’s disease (AD) have produced conflicting results, with some investigators suggesting that CSF is impaired generally1 and others reporting that CSF is normal in AD.2 An explanation for the discrepancy in results may involve the range of dementia severity represented by the subject groups in the two studies: Many moderately to severely demented subjects with AD are unable to perform particular CSF tests due to memory, attentional, or other deficits unrelated to visual skills. We have administered to a group of ten patients with AD, of a wide range of dementia severity, a CSF test with low task demands. Sinusoidal gratings of six spatial frequencies (1.5, 3, 6, 12, and 18 cycles/deg) and eight levels of contrast were displayed on photographic plates; subjects indicated the orientation of the gratings (vertical, left oblique, or right oblique). Patients who had been unable to perform tests of CSF involving monitor display of static vertical gratings performed ably with the photographic plates. The results indicate that CSF is depressed at each frequency tested for patients with AD relative to healthy age-matched subjects. This deficit appears to be unrelated to the severity of dementia.
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Malmqvist, Lars D., and Per G. Söderberg. "The Uppsala Contrast Sensitivity Test (UCST): A fast strategy for clinical assessment of contrast sensitivity." In SPIE BiOS, edited by Fabrice Manns, Per G. Söderberg, and Arthur Ho. SPIE, 2014. http://dx.doi.org/10.1117/12.2054403.

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Sidick, Erkin, Stuart Shaklan, and Kunjithapatham Balasubramanian. "HCIT broadband contrast performance sensitivity studies." In SPIE Optical Engineering + Applications, edited by Jean J. Dolne, Thomas J. Karr, Victor L. Gamiz, and David C. Dayton. SPIE, 2012. http://dx.doi.org/10.1117/12.979456.

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Apelt, Dörte, Hans Strasburger, Richard Rascher-Friesenhausen, Jan Klein, Bernhard Preim, and Heinz-Otto Peitgen. "Contrast sensitivity in mammographic softcopy reading." In SPIE Medical Imaging, edited by Berkman Sahiner and David J. Manning. SPIE, 2009. http://dx.doi.org/10.1117/12.810221.

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Reports on the topic "Contrast sensitivity"

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Monaco, William A., Kent E. Higgins, and Joel T. Kalb. Central and Off-Axis Spatial Contrast Sensitivity Measured with Gabor Patches. Fort Belvoir, VA: Defense Technical Information Center, September 2010. http://dx.doi.org/10.21236/ada532054.

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Hatcher, Donald J., Terry L. DeVietti, and John A. D'Andrea. Computer Software and Hardware to Determine Contrast Sensitivity Using Three Methods: Tracking, Limits, and Constant Stimuli. Fort Belvoir, VA: Defense Technical Information Center, December 1992. http://dx.doi.org/10.21236/ada265168.

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Jin, Hongyu, and Man Zhang. LR-5 by LI-RADS under contrast enhanced ultrasonography manifests satisfactory diagnostic performance for hepatocellular carcinoma: A systematic review and meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, October 2022. http://dx.doi.org/10.37766/inplasy2022.10.0011.

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Review question / Objective: To evaluate the relative diagnostic sensitivity, specificity, and accuracy of LR-5 under contrast-enhanced ultrasonography (CEUS) LI-RADS system in the differential diagnosis of hepatocellular carcinoma (HCC). Information sources: A comprehensive and thorough search of literature was carried out through internationally acknowledged medical literature resources database, including PubMed/MEDLINE, EMBASE, Ovid, and Web of Science along with regional databases with key research words of (“hepatocellular carcinoma” OR “liver cancer” OR “liver tumor” OR “liver nodule” OR “liver mass” OR “liver lesion”) AND (“contrast-enhanced US” OR “contrast-enhanced ultrasonography” OR “contrast-enhanced ultrasound” OR “CEUS”) AND (“LI-RADS” OR “liver reporting and data system”) for studies published between January 2017 and June 2021. We limited the language used in the literature as English only.
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Graville. L51764 Hydrogen Cracking in the Heat-Affected Zone of High-Strength Steels-Year 2. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), March 1997. http://dx.doi.org/10.55274/r0010170.

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During year 1 of this project a test to evaluate the sensitivity of the heat affected zone (HAZ) to hydrogen cracking was developed. This was in response to a need for a test which provided unambiguous results in contrast to existing test methods which often led to difficulties in interpretation. For example, WIC tests usually cracked in the weld metal rather than the HAZ and therefore did not produce a clear indication of the sensistivity of the HAZ. The new test involves a machined notch which can be placed in the HAZ thus forcing crack initiation to occur in the desired region. A further advantage of the new test is that it is quantitative with each test specimen providing a measure of the sensitivity of the HAZ in that test. Existing tests are usually of the crack/no-crack type requiring a series of tests at different preheats to be carried out in order to establish a critical value. This is an expensive, time-consuming approach. The new test measures the deflection to first load drop (normally the onset of significant cracking) when the welded specimen is loaded in bending. It was also shown during the first year of the project that the simple geometry of the test lends itself to easy analysis enabling the stress/strain distribution to be calculated by finite element analysis. The quantitative measurement of susceptibility in the test enabled the cracking of more complex welds to be predicted on the basis of a local critical hydrogen model. The objective of the work was to extend the notched bend test to the evaluation of weld metal sensitivity to hydrogen cracking. The experiments were designed to determine whether the test could discriminate between two different weld metals and to study the effects of reducing hydrogen content. In addition, finite element analysis of the weld metal test was carried out and finite difference analysis used to predict the local hydrogen concentration. This work modifies the notched bend test, developed for evaluating the sensitivity of the heat affected zone (HAZ), to allow the evaluation of weld metal. The results showed that weld metal could readily be evaluated, with the test discriminating among weld metals of different composition and hydrogen contact. Finite element analysis was undertaken and showed that for the two weld metals tested, cracking occurred at the same local stress when the hydrogen content was the same, despite differences in strength. A finite model was used to calculate the distribution of hydrogen as a function of aging time. Although the general trends were confirmed by the experimental measurements of hydrogen content, there was considerable scatter attributed to the small hydrogen volumes measured.
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Light. L51504 Investigation of Real-Time Radiographic Methods for Use in Pipeline Weld Inspection. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), October 1986. http://dx.doi.org/10.55274/r0010599.

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Conventional radiography has been the accepted nondestructive examination (NDT) method used for many years to either "accept" or "reject" a field weld in the pipeline industry. The cost of conventional radiography, however, increasingly has become a major concern in the cost effectiveness of laying new pipelines. The contributing factors to the high cost of conventional radiography are the costs of film and of the chemicals and manpower used to develop the film. Over the last few years, a newer approach to performing radiographic testing has been perfected. Called "real-time radiography," it uses radiographic sources with an optical imaging system. It has been developed now to the point that the sensitivity, contrast, and resolution of these imaging systems can be used to detect variations in material density equivalent to defects of interest in pipeline welds. The first objective of Phase 1 was to investigate existing real-time radiographic systems and system components in terms of their application to inspection of field-produced girth welds in steel pipelines. The second objective was to recommend a real-time system (either existing as a whole unit or comprised of several key subsystems) to be used for a field demonstration during Phase 2 of the program. The incentive, or goal, for this two-phase program is to introduce real-time radiography to the pipeline industry as a faster and overall more cost effective alternative NDE method compared to conventional film radiography. In addition, real-time radiography would provide a means to interpret the condition of a weld soon after completion while the welding team is still in the near vicinity of the inspected weld. This would permit immediate repair, if necessary, which would greatly reduce cost.
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Ori, Naomi, and Mark Estelle. Specific mediators of auxin activity during tomato leaf and fruit development. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597921.bard.

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The plant hormone auxin is involved in numerous developmental processes, including leaf and fruit development. The tomato (Solanumlycopersicum) gene ENTIRE (E) encodes an auxin-response inhibitor from the Aux/IAA family. While most loss-offunction mutations in Aux/IAA genes are similar to the wild type due to genetic redundancy, entire (e) mutants show specific effects on leaf and fruit development. e mutants have simple leaves, in contrast to the compound leaves of wild type tomatoes. In addition, e plants produce parthenocarpic fruits, in which fruit set occurs independently of fertilization. The aim of this research program was to utilize the e mutation to identify and characterize genes that mediate the specific effect of auxin in leaf and fruit development. The specific objectives of the project were to: 1. Characterize and map modifiers of the e leaf phenotype. 2. Characterize and map suppressors of the e fruit phenotype. 3. Dissect the developmental specificity of the E gene. 4. Examine the effect of fruit-overexpression of identified genes on fruit set and seed production. To identify mediators of auxin in leaf development, we mainly focused on one mutant, crawling elephant (crel, previously called t282), which showed substantial suppression of the e phenotype and other auxin-relatedphenotypes. We have identified the CREL gene as a homolog of the Arabidopsis VRN5 gene, involved in recruiting polycomb silencing complexes to specific targets. We showed that CREL affects auxin sensitivity in tomato. Suppressors of the e fruit phenotype have been further characterized and selected for more profound effects. Expression profiling by RNAseq was used to analyze the effect of e as well as crel on gene expression in leaves and fruits. This analysis has identified putative E and CREL targets. We have initiated studies to assess the role of some of these targets in flower and fruit development. The research has identified potential mediators of auxin response in leaf, flower and fruit development.
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Tao, Yang, Victor Alchanatis, and Yud-Ren Chen. X-ray and stereo imaging method for sensitive detection of bone fragments and hazardous materials in de-boned poultry fillets. United States Department of Agriculture, January 2006. http://dx.doi.org/10.32747/2006.7695872.bard.

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As Americans become increasingly health conscious, they have increased their consumptionof boneless white and skinless poultry meat. To the poultry industry, accurate detection of bonefragments and other hazards in de-boned poultry meat is important to ensure food quality andsafety for consumers. X-ray imaging is widely used for internal material inspection. However,traditional x-ray technology has limited success with high false-detection errors mainly becauseof its inability to consistently recognize bone fragments in meat of uneven thickness. Today’srapid grow-out practices yield chicken bones that are less calcified. Bone fragments under x-rayshave low contrast from meat. In addition, the x-ray energy reaching the image detector varieswith the uneven meat thickness. Differences in x-ray absorption due to the unevenness inevitablyproduce false patterns in x-ray images and make it hard to distinguish between hazardousinclusions and normal meat patterns even by human visual inspection from the images.Consequently, the false patterns become camouflage under x-ray absorptions of variant meatthickness in physics, which remains a major limitation to detecting hazardous materials byprocessing x-ray images alone.Under the support of BARD, USDA, and US Poultry industries, we have aimed todeveloping a new technology that uses combined x-ray and laser imaging to detect bonefragments in de-boned poultry. The technique employs the synergism of sensors of differentprinciples and has overcome the deficiency of x-rays in physics of letting x-rays work alone inbone fragment detection. X-rays in conjunction of laser-based imaging was used to eliminatefalse patterns and provide higher sensitivity and accuracy to detect hazardous objects in the meatfor poultry processing lines.Through intensive research, we have met all the objectives we proposed during the researchperiod. Comprehensive experiments have proved the concept and demonstrated that the methodhas been capable of detecting frequent hard-to-detect bone fragments including fan bones andfractured rib and pulley bone pieces (but not cartilage yet) regardless of their locations anduneven meat thickness without being affected by skin, fat, and blood clots or blood vines.
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Gamboa-Estrada, Fredy, and Andrés Sánchez-Jabba. The Effects of Foreign Investor Composition on Colombia´s Sovereign Debt Flows. Banco de la República Colombia, December 2022. http://dx.doi.org/10.32468/be.1222.

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Assessing the composition of sovereign debt holders is important because investors’ behavior varies according to distinctive components, including shareholders’ preferences, regulatory constraints, and profitability mandates. To study this issue, we examine the determinants of offshore investments of mutual funds and pension funds, which concentrate Colombia’s outstanding sovereign debt. Our results indicate that mutual funds exhibit considerable sensitivity to shocks in global factors, such as the Federal Funds Rate, sovereign risk, and the composition of financial indices. This contrasts with findings among pension funds, for which we detected no statistically significant effects when examining these factors, underlining the differences in foreign investor behavior that could impact sovereign debt flows within emerging markets.
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Ribeiro, João A., Paulo J. Pereira, and Elísio M. Brandão. A real options model to determine the optimal contractual penalty for a BOT project. CICEE. Universidade Autónoma de Lisboa, 2021. http://dx.doi.org/10.26619/ual-cicee/wp06.2021.

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Public-Private Partnerships (PPP) became one of the most common types of public procurement arrangements and Build-Own-Transfer (BOT) projects, awarded through adequate bidding competitions, have been increasingly promoted by governments. The theoretical model herein proposed is based on a contractual framework where the government grants leeway to the private entity regarding the timing for project implementation. However, the government is aware that delaying the beginning of operations will lead to the emergence of social costs, i.e., the costs that result from the corresponding loss of social welfare. This fact should motivate the government to include a contractual penalty in case the private firm does not implement the project immediately. The government also recognizes that the private entity is more efficient in constructing the project facility and also in running the subsequent operations. The model’s outcome is the optimal value for the legal penalty the government should include in the contract form. Sensitivity analysis reveals that there is a level for each of the comparative efficiency factors above which there is no need to impose a contractual penalty, for a given level of social costs. Finally, the effects of including a non-optimal penalty value in the contract form, which derives from overestimating or underestimating the selected bidder’s real comparative efficiency are examined, using a numerical example. Results demonstrate that overestimating (underestimating) the selected bidder’s real comparative efficiency leads to the inclusion of a below-optimal (above-optimal) value for the legal penalty in the contract and produces effects the government should prevent by estimating the comparative efficiency factors with full accurac.
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Wisniewski, Michael, Samir Droby, John Norelli, Dov Prusky, and Vera Hershkovitz. Genetic and transcriptomic analysis of postharvest decay resistance in Malus sieversii and the identification of pathogenicity effectors in Penicillium expansum. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597928.bard.

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Use of Lqh2 mutants (produced at TAU) and rNav1.2a mutants (produced at the US side) for identifying receptor site-3: Based on the fact that binding of scorpion alpha-toxins is voltage-dependent, which suggests toxin binding at the mobile voltage-sensing region, we analyzed which of the toxin bioactive domains (Core-domain or NC-domain) interacts with the DIV Gating-module of rNav1.2a. This analysis was based on the assumption that the dissociation of toxin mutants upon depolarization would vary from that of the unmodified toxin should the substitutions affect a site of interaction with the channel Gating-module. Using a series of toxin mutants (mutations at both domains) and two channel mutants that were shown to reduce the sensitivity to scorpion alpha-toxins, and by comparison of depolarization-driven dissociation of Lqh2 derivatives off their binding site at rNav1.2a mutant channels we found that the toxin Core-domain interacts with the Gating-module of DIV. Details of the experiments and results appear in Guret al (2011). Mapping receptor site 3 at Nav1.2a by extensive channel mutagenesis (Seattle): Since previous studies with photoaffinity labeling and antibody mapping implicated domains I and IV in scorpion alpha-toxin binding, Nav1.2 channel mutants containing substitutions at these extracellular regions were expressed and tested for receptor function by whole-cell voltage clamp. Of a large number of channel mutants, T1560A, F1610A, and E1613A in domain IV had ~5.9-, ~10.7-, and ~3.9-fold lower affinities for the scorpion toxin Lqh2, respectively, and mutant E1613R had 73-fold lower affinity. Toxin dissociation was accelerated by depolarization for both wild-type and mutants, and the rates of dissociation were also increased by mutations T1560A, F1610A and E1613A. In contrast, association rates for these three mutant channels at negative membrane potentials were not significantly changed and were not voltage-dependent. These results indicated that Thr1560 in the S1-S2 loop, Phe1610 in the S3 segment, and Glu1613 in the S3-S4 loop in domain IV participate in toxin binding. T393A in the SS2-S6 loop in domain I also showed a ~3.4-fold lower affinity for Lqh2, indicating that this extracellular loop may form a secondary component of the toxin binding site. Analysis with the Rosetta-Membrane algorithm revealed a three-dimensional model of Lqh2 binding to the voltage sensor in a resting state. In this model, amino acid residues in an extracellular cleft formed by the S1-S2 and S3-S4 loops in domain IV that are important for toxin binding interact with amino acid residues on two faces of the wedge-shaped Lqh2 molecule that are important for toxin action. The conserved gating charges in the S4 transmembrane segment are in an inward position and likely form ion pairs with negatively charged amino acid residues in the S2 and S3 segments (Wang et al 2011; Gurevitz 2012; Gurevitzet al 2013).
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