Journal articles on the topic 'Modal aberration'
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1
Zhang, Xiang. "Analyzing Output Phase Properties of Confocal Positive-Branch Laser Resonators by Use of Hartmann-Shack Sensor." Advanced Materials Research 282-283 (July 2011): 561–64. http://dx.doi.org/10.4028/www.scientific.net/amr.282-283.561.
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The effect of intracavity aberrated perturbation on output mode structure properties of passive confocal unstable resonator is been experimentally researched by adopting H-S wavefront sensor and Zernike modal wavefront reconstruction on the basis of numerical simulation. Results show that intracavity tilted perturbation notablely affects outcoupled intensity distribution, and will also increase some high-order aberrations of beam phase properties. However, low-order Zernike tilt aberration is the main component when phase-tilted perturbation is introduced into the resonator. Defocus, astigmatism and coma aberration will all be brought, and also such high-order aberration included in wavefront will directly degrade output beam quality. When correction device of adaptive optics adopted for intracavity aberration correction, correction of tilted aberration should be considered firstly.
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Lai, Xiaomin, Chen Xu, Yafeng Liu, Kaihua Wei, and Kaihua Wu. "Automatic Modal Wavefront Estimation and Correction for Optical Aberration." IEEE Photonics Journal 11, no. 1 (February 2019): 1–9. http://dx.doi.org/10.1109/jphot.2018.2888549.
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Kennedy, Chandler. "Helicoid modal analysis of laser oscillators with spherical aberration." Applied Optics 41, no. 33 (November 20, 2002): 6991. http://dx.doi.org/10.1364/ao.41.006991.
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Liu, Jian, Weisong Zhao, Chenguang Liu, Chenqi Kong, Yixuan Zhao, Xiangyan Ding, and Jiubin Tan. "Accurate aberration correction in confocal microscopy based on modal sensorless method." Review of Scientific Instruments 90, no. 5 (May 2019): 053703. http://dx.doi.org/10.1063/1.5088102.
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Villeneuve, Jean-Eudes, Albéric Boivin, and Subhash C. Biswas. "L'image tridimensionnelle du point en présence d'aberration sphérique primaire et de filtrage d'amplitude : unitaire ou modal." Canadian Journal of Physics 63, no. 2 (February 1, 1985): 287–300. http://dx.doi.org/10.1139/p85-046.
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We investigate the point diffraction image arising from an objective lens in the vicinity of its paraxial focus, under the combined influence of spherical aberration, defocusing, and an amplitude filtering of modal TEM00 law. The previous literature pertaining to our subject is first reviewed thoroughly and then we outline a new hybrid formalism that permits an easy computation of the total diffraction image everywhere in the focal region. In this formalism the complex pupil amplitude is developed into a series of Zernike polynomials, the coefficients of which are obtained through the Gauss–Chebyshev method of numerical quadrature. A considerable amount of numerical information has thus been obtained, which will be presented here in graphical form and discussed. Notably we show that our modal filter, combined with an appropriate amount of defocusing, does compensate the existing spherical aberration beyond the supposedly ideal situation represented by the Airy pattern.
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Hahn, K. A., R. C. Richardson, E. A. Hahn, and C. L. Chrisman. "Diagnostic and Prognostic Importance of Chromosomal Aberrations Identified in 61 Dogs with Lymphosarcoma." Veterinary Pathology 31, no. 5 (September 1994): 528–40. http://dx.doi.org/10.1177/030098589403100504.
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To determine the diagnostic and/or prognostic importance of chromosomal aberrations identified in dogs with malignant (non-Hodgkin's) lymphoma, clinical stages for 61 dogs with lymphosarcoma were determined, the lymph node(s) were histopathologically graded, and the malignant tissue lymphocytes were karyotyped. The results from life table survival curve analysis demonstrated that first remission length and survival time were significantly longer in 15 of 61 (25%) dogs that had a trisomy of chromosome 13 as the primary chromosomal aberration than in those dogs (46/61, 75%) with other primary chromosomal aberrations ( P < 0.05). Sex, age, weight, histopathologic subtype and grade, World Health Organization (WHO) clinical stage, WHO and modified Karnofsky performance status, chromosomal modal number, and treatment protocol were of no prognostic importance in predicting first remission length or survival time ( P > 0.05). Multivariate analysis did not identify a significant correlation between the prognostic groups or within the various prognostic subsets ( P > 0.05). The pathogenesis of canine and human non-Hodgkin's lymphoma, as observed cytogenetically, differs.
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Feng, Feng, Ian H. White, and Timothy D. Wilkinson. "Aberration Correction for Free Space Optical Communications Using Rectangular Zernike Modal Wavefront Sensing." Journal of Lightwave Technology 32, no. 6 (March 2014): 1239–45. http://dx.doi.org/10.1109/jlt.2014.2301634.
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Neil, M. A. A., M. J. Booth, and T. Wilson. "Closed-loop aberration correction by use of a modal Zernike wave-front sensor." Optics Letters 25, no. 15 (August 1, 2000): 1083. http://dx.doi.org/10.1364/ol.25.001083.
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Calderon-Uribe, Uriel, Geovanni Hernandez-Gomez, and Armando Gomez-Vieyra. "Measurement of Longitudinal Chromatic Aberration in the Last Crystalline Lens Surface Using Hartmann Test and Purkinje Images." Sensors 22, no. 7 (March 30, 2022): 2653. http://dx.doi.org/10.3390/s22072653.
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Research has shown that longitudinal chromatic aberration (LCA) of the human eye is generated across all of the eye’s optical surfaces. However, it may not be necessary to measure the LCA from the first surface of the cornea to the retina, as it is known that most of the changes that can modify the path of light occur from the first surface of the cornea to the last surface of the crystalline lens. This investigation presents the study of an objective technique that allows the measurement of longitudinal chromatic aberration (LCA) on the last crystalline lens surface by developing a pulse width wavefront system using a Hartmann test, Purkinje image, and Zernike polynomial. A blue pulse (440–480 nm) and a red pulse (580–640 nm) were used to generate a pattern of spots in the human eye. This pattern generated on the posterior surface of the crystalline lens of the human eye allows the reconstruction of the wavefront via a modal method with Zernike polynomials. Once the wavefront is reconstructed, Zernike coefficients can be used to quantify the LCA. The methodology and objective measurements of the magnitude of the longitudinal chromatic aberration of five test subjects are explained in this article.
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Moxham, Thomas E. J., David Laundy, Vishal Dhamgaye, Oliver J. L. Fox, Kawal Sawhney, and Alexander M. Korsunsky. "Aberration characterization of x-ray optics using multi-modal ptychography and a partially coherent source." Applied Physics Letters 118, no. 10 (March 8, 2021): 104104. http://dx.doi.org/10.1063/5.0041341.
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Lentzen, Markus. "Contrast Transfer and Resolution Limits for Sub-Angstrom High-Resolution Transmission Electron Microscopy." Microscopy and Microanalysis 14, no. 1 (December 21, 2007): 16–26. http://dx.doi.org/10.1017/s1431927608080045.
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The optimum imaging of an object structure at the sub-angstrom length scale requires precise adjustment of the lens aberrations of a high-resolution instrument up to the fifth order. A least-squares optimization of defocus aberrationC1, third-order spherical aberrationC3, and fifth-order spherical aberrationC5yields two sets of aberration coefficients for strong phase contrast up to the information limit: one for variableC1andC3, at fixedC5, another for variableC1,C3, andC5. An additional correction to the defocus aberration, dependent on object thickness, is described, which becomes important for the use of image simulation programs in predicting optimum high-resolution contrast from thin objects at the sub-angstrom scale. For instruments with a sub-angstrom information limit the ultimate structure resolution, the power to resolve adjacent atom columns in a crystalline object, depends on both the instrumental pointspread and an object pointspread due to finite width of the atomic column potentials. A simulation study on a simple double-column model yields a range for structure resolutions, dependent on the atomic scattering power, from 0.070 nm down to 0.059 nm, for a hypothetical 300-kV instrument with an information limit of 0.050 nm.
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Ottensmeyer, F. P. "Electron Spectroscopic Imaging and Analysis in the TEM: Have the Limits Been Reached." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 302–3. http://dx.doi.org/10.1017/s0424820100163976.
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Electron energy filtering in the transmission electron microscope has had two major applications: 1) contrast enhancement in the image by elimination of chromatic aberrations, and 2) microanalysis by utilization of the information carried in the electron energy loss spectrum.The first application is unique to the fixed beam electron microscope, in which the image suffers from the interaction of the imaging lens with a broad spectrum of electron energies. Since the modal energy loss in the spectrum of 100 kV electrons traversing a carbonaceous light-atom material is about 25 eV per mean-free-path length in the specimen, a lens even with a chromatic aberration constant as good as 1 mm will blur the corresponding image to about 25 Å. In the STEM in which no imaging lenses are used after the electron beam has interacted with the specimen, chromatic aberrations do not occur; at most an effect due to the non-localization of the electron-specimen interaction may be detected as a blurring due to low-loss electrons. Even in the TEM, the effect of energy filtering to use only elastic electrons is small for bright field images of thin specimens stained with heavy atoms, since contrast and visibility is achieved primarily from the predominant elastic scatter from the heavy atoms. However, for dark field microscopy of unstained specimens the effect of filtering is dramatic, since for carbon atoms inelastic scattering dominates elastic scattering by a ratio of 3 to I.
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Pishas, Kathleen I., and Stephen L. Lessnick. "Recent advances in targeted therapy for Ewing sarcoma." F1000Research 5 (August 25, 2016): 2077. http://dx.doi.org/10.12688/f1000research.8631.1.
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Ewing sarcoma is an aggressive, poorly differentiated neoplasm of solid bone that disproportionally afflicts the young. Despite intensive multi-modal therapy and valiant efforts, 70% of patients with relapsed and metastatic Ewing sarcoma will succumb to their disease. The persistent failure to improve overall survival for this subset of patients highlights the urgent need for rapid translation of novel therapeutic strategies. As Ewing sarcoma is associated with a paucity of mutations in readily targetable signal transduction pathways, targeting the key genetic aberration and master regulator of Ewing sarcoma, the EWS/ETS fusion, remains an important goal.
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Бенуни, А. А., and В. Я. Колючкин. "Компенсация погрешностей модели центральной проекции в трехмерных сканерах." Журнал технической физики 127, no. 10 (2019): 631. http://dx.doi.org/10.21883/os.2019.10.48368.193-19.
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AbstractPinhole model measurement errors in 3D triangulation based scanners is studied in the present work. Pupil aberrations of the scanner lenses are shown to cause noticeable errors in determining the coordinates of surface points. The requirements for aberration characteristics are formulated to minimize the error of 3D scanners. A modification of the pinhole model allowing a decrease in the error induced by pupil aberration of lenses of triangulation-based scanners is proposed as well.
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Yang, Lin, Zhenyu Ma, Siqi Liu, Qingbin Jiao, Jiahang Zhang, Wei Zhang, Jian Pei, et al. "Study of the Off-Axis Fresnel Zone Plate of a Microscopic Tomographic Aberration." Sensors 22, no. 3 (February 1, 2022): 1113. http://dx.doi.org/10.3390/s22031113.
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A tomographic microscopy system can achieve instantaneous three-dimensional imaging, and this type of microscopy system has been widely used in the study of biological samples; however, existing chromatographic microscopes based on off-axis Fresnel zone plates have degraded image quality due to geometric aberrations such as spherical aberration, coma aberration, and image scattering. This issue hinders the further development of chromatographic microscopy systems. In this paper, we propose a method for the design of an off-axis Fresnel zone plate with the elimination of aberrations based on double exposure point holographic surface interference. The aberration coefficient model of the optical path function was used to solve the optimal recording parameters, and the principle of the aberration elimination tomography microscopic optical path was verified. The simulation and experimental verification were carried out utilizing a Seidel coefficient, average gradient, and signal-to-noise ratio. First, the aberration coefficient model of the optical path function was used to solve the optimal recording parameters. Then, the laminar mi-coroscopy optical system was constructed for the verification of the principle. Finally, the simulation calculation results and the experimental results were verified by comparing the Seidel coefficient, average gradient, and signal-to-noise ratio of the microscopic optical system before and after the aberration elimination. The results show that for the diffractive light at the orders 0 and ±1, the spherical aberration W040 decreases by 62–70%, the coma aberration W131 decreases by 96–98%, the image dispersion W222 decreases by 71–82%, and the field curvature W220 decreases by 96–96%, the average gradient increases by 2.8%, and the signal-to-noise ratio increases by 18%.
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Polishchuk, Oleksandr, Vasiliy Kozyar, and Dmytro Zhaboiedov. "Method for reducing longitudinal spherical aberration of intraocular lenses." Eastern-European Journal of Enterprise Technologies 1, no. 5(115) (February 25, 2022): 14–22. http://dx.doi.org/10.15587/1729-4061.2022.251521.
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It has been established that of all types of aberrations following the implantation of intraocular lenses, the most significant is spherical, inherent in the spherical optics in various aspects. This paper proposes a method for reducing the longitudinal spherical aberration of intraocular lenses by applying an additional optical layer onto their surface. To reduce spherical aberration, the thickness of a layer of polytetrafluoroethylene (Teflon) was simulated in the programming environment Zemax 13 (USA). Calculations that were performed included refractive indices of the environment and the material of the optics. It was established that in order to reduce the value of the longitudinal spherical aberration of an intraocular lens made of hydrophobic acrylic, the thickness of aTeflon layer should be about 100 nm. The results of spraying indicate an improvement in the optical characteristics of the lens by reducing longitudinal spherical aberration. When examining different areas of lenses with spraying, it was established that there is no spherical aberration in the lens area. In the 4 mm zone, the spherical aberration indicator decreased by 4 times compared to the original lens. In the region with a diameter of 6 mm, spherical aberration decreased by 0.2. Applying a layer of Teflon reduced Fresnel reflection by 4 times, which improves the sensitivity and contrast of vision. The hydrophobic properties of Teflon provide the anti-adhesive state of the lens, which is a counteraction to the development of secondary cataracts. The SolidWorks 19 software (France) was used to design a model of the lens "NVision Optics" whose aberrations were eliminated as much as possible
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Liu, Yongkai, Jianli Wang, Lie Ma, Shijie Gao, Chenzi Guo, Kainan Yao, and Lei Sheng. "The Effect of Spatial Mode Distribution on Coupling Efficiency of Single-Mode Fiber: Theoretical Analysis and Experimental Verification." Applied Sciences 9, no. 16 (August 11, 2019): 3296. http://dx.doi.org/10.3390/app9163296.
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In this study, Zernike polynomials and optical fiber field theory are applied to build a mathematical model of coupling efficiency (CE) and spatial mode of aberrations. The theory built in this paper can be used to quickly calculate the CE affected by a single aberration as well as the aberrations caused by atmospheric turbulence. The aberrations are classified based on Zernike polynomials and the effects of aberrations on CE of different types and different spatial frequencies are analyzed. The influence of the effects of AO system residual errors is also analyzed. Adaptive optics (AO) equipment is applied to build a system on which the proposed theory was tested; the experimental results validate the theoretical analysis.
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Tröger, Jessica, Christian Hoischen, Birgit Perner, Shamci Monajembashi, Aurélien Barbotin, Anna Löschberger, Christian Eggeling, Michael M. Kessels, Britta Qualmann, and Peter Hemmerich. "Comparison of Multiscale Imaging Methods for Brain Research." Cells 9, no. 6 (June 1, 2020): 1377. http://dx.doi.org/10.3390/cells9061377.
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A major challenge in neuroscience is how to study structural alterations in the brain. Even small changes in synaptic composition could have severe outcomes for body functions. Many neuropathological diseases are attributable to disorganization of particular synaptic proteins. Yet, to detect and comprehensively describe and evaluate such often rather subtle deviations from the normal physiological status in a detailed and quantitative manner is very challenging. Here, we have compared side-by-side several commercially available light microscopes for their suitability in visualizing synaptic components in larger parts of the brain at low resolution, at extended resolution as well as at super-resolution. Microscopic technologies included stereo, widefield, deconvolution, confocal, and super-resolution set-ups. We also analyzed the impact of adaptive optics, a motorized objective correction collar and CUDA graphics card technology on imaging quality and acquisition speed. Our observations evaluate a basic set of techniques, which allow for multi-color brain imaging from centimeter to nanometer scales. The comparative multi-modal strategy we established can be used as a guide for researchers to select the most appropriate light microscopy method in addressing specific questions in brain research, and we also give insights into recent developments such as optical aberration corrections.
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Göhring, Gudrun, Simone Feurstein, Winfried Hofmann, Arnold Ganser, Hans H. Kreipe, and Brigitte Schlegelberger. "Routes of Clonal Evolution Into Complex Karyotypes in Myelodysplastic Syndrome Patients with Del(5q)." Blood 120, no. 21 (November 16, 2012): 522. http://dx.doi.org/10.1182/blood.v120.21.522.522.
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Abstract Abstract 522 Introduction: A complex karyotype, detected in approximately 10%-15% of patients with myelodysplastic syndromes (MDS), is associated with a very short median survival and a high risk of transformation into AML. The most frequent chromosome aberration in complex karyotypes is a deletion of 5q (del(5q)). It is still unclear, how complex karyotypes develop. One possibility is via stepwise accumulation of chromosome aberrations according to the so-called Vogelstein model (Fearon ER, Vogelstein B, Cell 1990; 61:759–67). Another possibility is a one-step catastrophic event called chromothripsis that seems to be associated with TP53 inactivation (Rausch T et al., Cell 2012;148:59–71). We recently described that leukemic progression in low-grade MDS with isolated del(5q) is associated with clonal evolution (Tehranchi R et al., N Engl J Med 2010;363:1025–37, Göhring G et al., Ann Hematol 2010; 89:365–74) and identified TP53 mutations and excessive telomere shortening as driving forces for clonal evolution and leukemic progression in MDS with del(5q) (Jädersten M et al., J Clin Oncol 2011; 29:1971–9, Göhring G et al., Leukemia 2012; 26:356–8). Yet, the modes of clonal evolution and the mechanisms responsible for the induction of chromosomal instability in MDS with isolated del(5q) remain largely unclear. Patients and Methods: Among 1645 patients with MDS and del(5q) investigated cytogenetically in our institution, 157 patients (9.5%) acquired additional aberrations and thus underwent clonal evolution. We reviewed the cytogenetic follow-up data of the 157 patients and carefully evaluated all additional aberrations, particularly those of complex karyotypes, which are defined as at least 3 aberrations, i.e. del(5q) and two additional chromosome abnormalities. Moreover, we investigated the clonal heterogeneity and the presence of independent clones, defined as clones that do not contain a del(5q). Results: During follow-up, 76 of 157 patients (48%) acquired two or more aberrations, thus evolving into a complex karyotype. Eighty-nine of 157 patients (57%) underwent a stepwise accumulation of additional aberrations (range 1–8, median: 1), while 38 patients (24%) developed highly complex clones (no of aberrations: 3–35, median: 7.5) at one time point during follow-up. This “catastrophic” route led to the development of a complex karyotype significantly more frequently than the stepwise accumulation of chromosome aberrations (38 of 38 cases compared to 38 of 89 patients; p<0.00001). In 12 cases, the complex clones were preceded by a clone containing one additional aberration, e.g. −7, del(12p) or del(17p). Independent clones that did not contain a del(5q) were detected in 43 of 157 patients (27%). A few aberrations were seen significantly more frequently in complex karyotypes than as single additional aberrations, e.g. −7/del(7q) (p=0.0001), del(9p) (p=0.01), +11/add(11q) (p=0.0003), −11/del(11q) (p=0.03), −16/del(16q) (p=0.0006), −17/del(17p) (p=0.00001), and +22/add(22q) (p=0.006). Trisomy 8 (p=0.008) and trisomy 21 (p=0.00001) occurred mostly in del(5q) clones with one additional aberration. Trisomy 8 was the most frequent aberration in independent clones. Conclusions: Although MDS with del(5q) is assumed to be a genetically stable hematologic neoplasm, clonal evolution, even into complex karyotypes, occurs in a significant proportion of patients. There are two routes of clonal evolution. One route of stepwise acquisition of additional aberrations resulted in clonal selection of clones that had accumulated mostly only one or two additional aberrations. In contrast, the other route led to an immediate development of highly complex clones. In some of these cases, this catastrophic event was preceded by the acquisition of one aberration, repeatedly by loss of 12p or loss of 17p harboring the ETV6/TEL and TP53 genes, respectively. These data provide further evidence that the inactivation of TP53 seems to play an important role in clonal evolution and leukemic progression. Disclosures: No relevant conflicts of interest to declare.
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Haaber, Jacob, Anne G. Sørensen, Anne Nibe, Ole Nielsen, Niels Abildgaard, Torben Plesner, and Gitte B. Kerndrup. "Interphase FISH in Multiple Myeloma." Blood 108, no. 11 (November 16, 2006): 5023. http://dx.doi.org/10.1182/blood.v108.11.5023.5023.
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Abstract 192 patients with multiple myeloma (MM) and benign monoclonal gammopathy of undetermined significance (MGUS, n=10) were investigated by interphase fluorescence in-situ hybridisation (iFISH) without (n= 132) and with positive plasma cell identification (PC-ID+) (n= 50). 134 were investigated at diagnosis 32 at time of progression, 7 at time of relapse and 9 were investigated with partial remission or no response. 10 of the MM cases were investigated twice. The patients were investigated with FISH probes detecting 11q23 (n=61), 13q13-14 (n=181), 14q32 ((n=121), 17p13.1 (n=181), t(4;14) (n=76) and t(11;14) (n=73). 61/132 (46%) of patients investigated without PC-ID+ showed abnormalities as opposed to 45/49 of evaluable cases (92%) with PC-ID+. The increase in abnormal cases was mainly due to the detection of more cases with loss of 13q and 17p and der(14)(q32): For patients investigated at diagnosis without and with PC-ID+, respectively: 13q-: 17% and 28%, 17p-: 3% and 15%, and 14q split signals (excluding the specific translocations): 8% and 24%. Based on the relatively small number investigated, the t(4;14) and the t(11;14) were not detected more frequently. G-band cytogenetics was carried out in 72 patients (25 without PC-ID+ and 47 with PC-ID+). 19 cases were abnormal (26%). Concordance for 1 or more aberration was found in 14 patients. t(11;14) was detected by both methods in 4 of 5 patients. Out of 7 cases with either near-tetraploidy/triploidy or hypoploidy in the G-band karyotypes, the modal number in the G-banded karyotypes could not be elucidated with certainty in 4 by iFISH with the applied probes. 7/10 patients investigated twice by iFISH showed new abnormalities on reinvestigation, 5 of these had a normal 1st analysis. 3 of 10 MGUS patients showed abnormalities. In conclusion, PC-ID+ is important for the detection of numerical aberrations and disclosing translocations involving 14q32, as translocations involving the IgH locus are frequent occurring in 64 % (n = 32) at diagnosis. Of these the t(4;14) and the t(11;14) constituted 8% and 20%, respectively. Re-examination of patients with a normal analysis should be considered in non-responders and progressing patients. Lastly, by applying the set of probes we chose in accordance with the proposed recommendations from the European Myeloma Network FISH Workshop, Royal Marsden Hospital, London UK, March 2005, failure to accurately the exsistence of detect near-tetraploid/near-triploid-, and hypoploid clones, is not insignificant (26%) and, based on the small number of cytogenetically abnormal cases it is recommended to include extra probes to classify the patients according to modal number by iFISH.
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Ida, T., H. Hibino, and H. Toraya. "Deconvolution of instrumental aberrations for synchrotron powder X-ray diffractometry." Journal of Applied Crystallography 36, no. 2 (March 15, 2003): 181–87. http://dx.doi.org/10.1107/s0021889802021131.
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A method to remove the effects of instrumental aberrations from the whole powder diffraction pattern measured with a high-resolution synchrotron powder diffractometer is presented. Two types of asymmetry in the peak profiles caused by (i) the axial-divergence aberration of the diffractometer (diffractometer aberration) and (ii) the aberration of the monochromator and focusing optics on the beamline (beamline aberration) are both taken into account. The method is based on the whole-pattern deconvolution by Fourier technique combined with the abscissa-scale transformation appropriate for each instrumental aberration. The experimental powder diffraction data of LaB6(NIST SRM660) measured on beamline BL-4B2at the Photon Factory in Tsukuba have been analysed by the method. The formula of the scale transformation for the diffractometer aberration hasa prioribeen derived from the instrumental function with geometric parameters of the optics. The strongly deformed experimental peak profiles at low diffraction angles have been transformed to sharp peak profiles with less asymmetry by the deconvolution of the diffractometer aberration. The peak profiles obtained by the deconvolution of the diffractometer aberration were modelled by an asymmetric model profile function synthesized by the convolution of the extended pseudo-Voigt function and an asymmetric component function with an empirical asymmetry parameter, which were linearly dependent on the diffraction angle. Fairly symmetric peak profiles have been obtained by further deconvolution of the empirically determined asymmetric component of the beamline aberration.
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Deng, Yangchun, Junlei Zhao, Yun Dai, and Yudong Zhang. "Simultaneous quantification of longitudinal and transverse ocular chromatic aberrations with Hartmann–Shack wavefront sensor." Journal of Innovative Optical Health Sciences 11, no. 04 (July 2018): 1850021. http://dx.doi.org/10.1142/s1793545818500219.
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A simple method to objectively and simultaneously measure eye’s longitudinal and transverse chromatic aberrations was proposed. A dual-wavelength wavefront measurement system using two Hartmann–Shack wavefront sensors was developed. The wavefronts of the red (639.1[Formula: see text]nm) and near-infrared (786.0[Formula: see text]nm) lights were measured simultaneously for different positions in the model eye. The chromatic wavefronts were converted into Zernike polynomials. The Zernike tilt coefficient (first term) was used to calculate the transverse chromatic aberration along the [Formula: see text]-direction, while the Zernike defocus coefficient (fourth term) was used to calculate the longitudinal chromatic aberration. The measurement and simulation data were consistent.
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Wei, Xiang, Yuanyuan Wang, Zhan Cao, Dziki Mbemba, Azhar Iqbal, and Zhizheng Wu. "Large Aberration Correction by Magnetic Fluid Deformable Mirror with Model-Based Wavefront Sensorless Control Algorithm." International Journal of Molecular Sciences 20, no. 15 (July 28, 2019): 3697. http://dx.doi.org/10.3390/ijms20153697.
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Magnetic fluid is a stable colloidal suspension of nano-sized, single-domain ferri/ferromagnetic particles dispersed in a liquid carrier. The liquid can be magnetized by the ferromagnetic particles aligned with the external magnetic field, which can be used as a wavefront corrector to correct the large aberrations up to more than 100 µm in adaptive optics (AO) systems. Since the measuring range of the wavefront sensor is normally small, the application of the magnetic fluid deformable mirror (MFDM) is limited with the WFS based AO system. In this paper, based on the MFDM model and the relationship between the second moment (SM) of the aberration gradients and the far-field intensity distribution, a model-based wavefront sensorless (WFSless) control algorithm is proposed for the MFDM. The correction performance of MFDM using the model-based control algorithm is evaluated in a WFSless AO system setup with a prototype MFDM, where a laser beam with unknown aberrations is supposed to produce a focused spot on the CCD. Experimental results show that the MFDM can be used to effectively compensate for unknown aberrations in the imaging system with the proposed model-based control algorithm.
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Chau, Gustavo, Marko Jakovljevic, Roberto Lavarello, and Jeremy Dahl. "A Locally Adaptive Phase Aberration Correction (LAPAC) Method for Synthetic Aperture Sequences." Ultrasonic Imaging 41, no. 1 (September 15, 2018): 3–16. http://dx.doi.org/10.1177/0161734618796556.
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Phase aberration is a phenomenon caused by heterogeneity of the speed of sound in tissue, in which the actual speed of sound of the tissue is different than the assumed speed of sound used for beamforming. It reduces the quality and resolution of ultrasonic images and impairs clinical diagnostic capabilities. Although phase aberration correction (PAC) methods can reduce these detrimental effects, most practical implementations of PAC methods are based on the near field phase screen model, which have limited ability to represent the true aberration induced by inhomogeneous tissue. Accordingly, we propose a locally adaptive phase aberration correction (LAPAC) method that is applied through the use of synthetic aperture. The method is tested using full-wave simulations of models of human abdominal wall, experiments with tissue aberrators, and in vivo carotid images. LAPAC is compared with conventional phase aberration correction (cPAC) where aberration profiles are computed at a preselected depth and applied to the beamformer’s time delays. For all experiments, LAPAC shows an average of 1 to 2 dB higher contrast than cPAC, and enhancements of 3 to 7 dB with respect to the uncorrected cases. We conclude that LAPAC may be a viable option to enhance ultrasound image quality images even in the presence of clinically relevant aberrating conditions.
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Trahey, Gregg E., and Stephen W. Smith. "Properties of Acoustical Speckle in the Presence of Phase Aberration Part I: First Order Statistics." Ultrasonic Imaging 10, no. 1 (January 1988): 12–28. http://dx.doi.org/10.1177/016173468801000102.
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The first order statistical properties of acoustical speckle patterns are studied as a function of several types of random and structured phase error. Such errors may arise from tissue velocity inhomogeneities or limitations in the acoustical imaging system. In this paper, we review the theory describing the statistical properties of speckle, describe a computer model which predicts the mean speckle brightness in the presence of phase aberrations, and report experiments in which we measure the effect of these aberrations on speckle brightness and variance. We find that the average speckle brightness is significantly reduced by even mild phase aberrations. The phase aberrations studied include focal point errors, random phase errors, and structured errors. Good agreement is found between experiment and computer simulation. We then discuss the implications of these results for imaging through aberrating media, tissue characterization and phase compensation methods.
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Sukovich, Jonathan R., Timothy L. Hall, Sang-Won Choi, Mahmoud Komaiha, Ning Lu, Dave Choi, and Zhen Xu. "Neuronavigation-guided transcranial histotripsy, results in a cadaveric model." Journal of the Acoustical Society of America 152, no. 4 (October 2022): A154. http://dx.doi.org/10.1121/10.0015864.
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Results from neuronavigation-guided transcranial histotripsy treatments in cadaveric models are presented. Histotripsy treatments were delivered transcranially to the brains of 3 cadavers (<96-h post-mortem) using a 30-cm diameter, 700-kHz, 360-element, transmit-receive capable transcranial histotripsy array. Pre-treatment CT and MRI scans of the head were acquired. A clinical neuronavigation system was used to coregister the histotripsy array with the cadaver head and guide treatments. Two-step aberration correction, combining pre-treatment CT-based correction and intra-procedure acoustic cavitation emission (ACE)-based correction, was employed to correct for skull-induced acoustic aberrations. Cavitation was generated at rates up to 200-Hz, and steered through 1-cm wide cubic targets in the brain. ACE signals were acquired throughout treatments using the array elements as receivers and used to localize cavitation and monitor treatment.Transcranial histotripsy was successfully applied to generate lesions in the cadaver brains. Two-step aberration correction resulted in significant improvements in focal quality and pressure. ACE-based cavitation localization could be achieved at rates up to 120-Hz. Neuronavigation-based coregistration/targeting errors ranged from 3 to 9-mm, but workflow issues have been identified and refinements have since reduced targeting errors to ≤1.5-mm. Changes in ACE signal features throughout treatments were observed to correlate with morphological observations of induced damage.
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Scholten, S. C., I. O. Robertson, G. J. Abrahams, Priya Singh, A. J. Healey, and J. P. Tetienne. "Aberration control in quantitative widefield quantum microscopy." AVS Quantum Science 4, no. 3 (September 2022): 034404. http://dx.doi.org/10.1116/5.0114436.
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Widefield quantum microscopy based on nitrogen-vacancy (NV) centers in diamond has emerged as a powerful technique for quantitative mapping of magnetic fields with a sub-micrometer resolution. However, the accuracy of the technique has not been characterized in detail so far. Here, we show that optical aberrations in the imaging system may cause large systematic errors in the measured quantity beyond trivial blurring. We introduce a simple theoretical framework to model these effects, which extends the concept of a point spread function to the domain of spectral imaging. Using this model, the magnetic field imaging of test magnetic samples is simulated under various scenarios, and the resulting errors are quantified. We then apply the model to previously published data, show that apparent magnetic anomalies can be explained by the presence of optical aberrations, and demonstrate a post-processing technique to retrieve the source quantity with improved accuracy. This work presents a guide to predict and mitigate aberration induced artifacts in quantitative NV-based widefield imaging and in spectral imaging more generally.
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Song, Yinyu, Lihua Fang, Ruirui Du, Luchao Lin, and Xingming Tao. "The corneal biomechanical changes after SMILE and LASIK refractive surgery were compared based on finite element analysis." E3S Web of Conferences 271 (2021): 03045. http://dx.doi.org/10.1051/e3sconf/202127103045.
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The three-dimensional (3D) finite element model of human eye was established, and the intraocular pressure (IOP) was loaded to simulate refractive surgery. The biomechanical properties of human cornea after SMILE and LASIK surgery were studied from the stress, strain and induced wavefront aberration. Our results showed that SMILE had less impact on the biomechanics, having less stress and strain changes than LASIK. However, the stress and strain of the cornea increased with the increase of the diopter and were concentrated in the central region. We also investigated the changes in wavefront aberrations of the cornea after surgery, and the results indicated that the defocus and vertical commotion were significantly affected by SMILE and LASIK surgery, while the remaining aberrations were approximately unchanged. In conclusion, both SMILE and LASIK sergury procedures changed the postoperative corneal biomechanics, but SMILE had less impact on the biomechanics of corneal.
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Villa, María, Francisco Cavas, and David P. Piñero. "Optical Impact of Corneal Clearance in Healthy Eyes Fitted with Scleral Contact Lenses: A Pilot Study." Journal of Clinical Medicine 11, no. 12 (June 14, 2022): 3424. http://dx.doi.org/10.3390/jcm11123424.
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This pilot study was conducted to evaluate the effect on refraction and optical quality of the increase in the corneal clearance after fitting a specific model of scleral contact lens (ScCL) in healthy subjects. A total of 15 eyes from 15 subjects were enrolled in the study, with evaluation of refraction, ocular aberrations and central corneal clearance with the same model of ScCL (ICD Toric, Paragon Vision Science, Gilbert, AZ, USA), but using 3 different sagittal heights: 4200, 4500 and 4800 µm. Mean values of corneal clearance for each ScCL fitted were 418.1 ± 112.1, 706.5 ± 120.3 and 989.9 ± 117.0 µm, respectively. Significant changes were detected in the spherical equivalent and high-order aberrations, especially coma and spherical aberration, when fitting ScCLs of increasing sagittal heights compared to the pre-fitting values. In conclusion, the increase in central corneal clearance when fitting ScCLs affects refraction, leading to a more myopic refractive error, and inducing an increase in different ocular HOAs. This should be considered when fitting ScCLs, especially multifocal designs.
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Wreesmann, Volkert B., Weiji Shi, Howard T. Thaler, Ashok Poluri, Dennis H. Kraus, David Pfister, Ashok R. Shaha, Jatin P. Shah, Pulivarthi H. Rao, and Bhuvanesh Singh. "Identification of Novel Prognosticators of Outcome in Squamous Cell Carcinoma of the Head and Neck." Journal of Clinical Oncology 22, no. 19 (October 1, 2004): 3965–72. http://dx.doi.org/10.1200/jco.2004.01.094.
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Purpose The goal of this study was to identify chromosomal aberrations associated with poor outcome in patients with head and neck squamous cell carcinoma (HNSCC). Patients and Methods We assessed the global genomic composition of 82 HNSCCs from previously untreated patients with comparative genomic hybridization (CGH). The CGH data were subcategorized into individual cytogenetic bands. Only genomic aberrations occurring in more than 5% of cases were analyzed, and redundancies were eliminated. Each aberration was submitted to univariate analysis to assess its relationship with disease-specific survival (DSS). We used Monte Carlo simulations (MCS) to adjust P values for the log-rank approximate χ2 statistics for each abnormality and further applied the Hochberg-Benjamini procedure to adjust the P values for multiple testing of the large number of abnormalities. We then submitted abnormalities whose univariate tests resulted in an adjusted P value of less than .15 together with significant demographic/clinical variables to stepwise Cox proportional hazards regression. We again verified and adjusted P values for the χ2 approximation of the final model by MCS. Results CGH analysis revealed a recurrent pattern of chromosomal aberrations typical for HNSCC. Univariate analysis revealed 38 abnormalities that were correlated with DSS. After controlling for multiple comparisons and confounding effects of stage, five chromosomal aberrations were significantly associated with outcome, including amplification at 11q13, gain of 12q24, and losses at 5q11, 6q14, and 21q11 (MCS adjusted P = .0009 to P = .01). Conclusion HNSCC contains a complex pattern of chromosomal aberrations. A sequential approach to control for multiple comparisons and effect of confounding variables allows the identification of clinically relevant aberrations. The significance of each individual abnormality merits further consideration.
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Jing, Dalan, Xiaodan Jiang, Xiaotong Ren, Jie Su, Shanshan Wei, Ran Hao, Yilin Chou, and Xuemin Li. "Change Patterns in Corneal Intrinsic Aberrations and Nerve Density after Cataract Surgery in Patients with Dry Eye Disease." Journal of Clinical Medicine 11, no. 19 (September 27, 2022): 5697. http://dx.doi.org/10.3390/jcm11195697.
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This study aimed to evaluate the change patterns in corneal intrinsic aberrations and nerve density after cataract surgery in dry eye disease. The preoperative, 1- and 3-month postoperative dry eye-related parameters were obtained by the Oculus keratograph and the ocular surface disease index questionnaire. The corneal intrinsic aberrations were measured using the Pentacam HR system. In vivo confocal microscopy was performed to observe the vortical and peripheral corneal nerves. An artificial intelligence technique run by the deep learning model generated the corneal nerve parameters. Corneal aberrations on the anterior and total corneal surfaces were significantly increased at 1 month compared with the baseline (p < 0.05) but gradually returned to the baseline by 3 months (p > 0.05). However, the change in posterior corneal aberration lasted up to 3 months (p < 0.05). There was a significant decrease in the corneal vortical nerve maximum length and average density after the operation (p < 0.05), and this damage lasted approximately 3 months. The corneal vortical nerve maximum length and average density were negatively correlated with the anterior corneal surface aberrations before and 1 month after the operation (correlation coefficients, CC = −0.26, −0.25, −0.28; all p < 0.05). Corneal vortex provided a unique site to observe long-term corneal nerve injury related to eye dryness. The continuous damage to the corneal vortical nerve may be due to the continuous dry eye state.
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Liu, Shiyuan, Shuang Xu, Xiaofei Wu, and Wei Liu. "Iterative method for in situ measurement of lens aberrations in lithographic tools using CTC-based quadratic aberration model." Optics Express 20, no. 13 (June 12, 2012): 14272. http://dx.doi.org/10.1364/oe.20.014272.
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Pérez-Gracia, Jesús, Francisco J. Ávila, Jorge Ares, Juan A. Vallés, and Laura Remón. "Misalignment and tilt effect on aspheric intraocular lens designs after a corneal refractive surgery." PLOS ONE 15, no. 12 (December 14, 2020): e0243740. http://dx.doi.org/10.1371/journal.pone.0243740.
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Purpose To numerically evaluate and compare the tolerance to misalignment and tilt of aspheric intraocular lenses (IOLs) designed for three eyes: with standard cornea and with simulated corneas after myopic and hyperopic laser ablation surgery. Methods Three aspheric IOLs of +20.00 diopter (D) with different spherical aberration (SA) (Z40) values have been designed using a theoretical model eye. Drastic changes on the theoretical eye anterior corneal asphericity have been performed to simulate myopic and hyperopic refractive surgeries. The effect of IOL misalignment and tilt on the image quality has been evaluated using a commercial optical software design for the three eye models. Image quality was assessed from the modulation transfer function (MTF), root mean square (RMS) values of defocus, astigmatism, coma and spherical aberration (Z40), and retinal images obtained from a visual simulator using an aleatory optotype of 0.00 LogMar visual acuity (VA). Results IOL misalignment and tilt reduced MTF values in general, and increased wavefront aberrations errors. Aberration-free IOLs maintained best the MTF values when misalignments were applied, together with good on-axis optical quality. IOLs with negative SA (Z40) correction decreased the MTF value under 0.43 for misalignments values higher than 0.50 mm with the three corneas. The effect of misalignment on RMS astigmatism and coma was correlated with the IOL SA (Z40) and with the three corneas. Conclusions This theoretical study shows that the largest degradation in image quality arises for the IOL with the highest amount of spherical aberration (Z40). Moreover, it has been found that the aspherical design has a more influential role in misalignment tolerance than in tilt tolerance.
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Liu, Yongming, Yujian Rui, Zhuanzhe Zhao, Manman Xu, and Yang Zhou. "Topology Optimization Design of an Active Deformable Mirror Based on Discrete Orthogonal Zernike Polynomials." Symmetry 14, no. 11 (November 21, 2022): 2469. http://dx.doi.org/10.3390/sym14112469.
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In order to design an active deformation mirror for projection objective aberration imaging quality control, a topology optimization design method of active deformation mirrors based on discrete orthogonal Zernike polynomials is proposed in this paper. Firstly, in order to solve the problem that continuous Zernike polynomials do not have orthogonality on the discrete coordinates inside the unit circle, which causes the instability of topology optimization results, discrete orthogonal Zernike polynomials are used to characterize the active deformation mirror wave aberrations. Then, the optical and structural deformations are combined to establish an optical-mechanical coupling topology optimization model with the help of the variable density method to derive the sensitivity of the mathematical model. Finally, a wave aberration corrected deformation mirror in an optical machine system is used as an arithmetic example for topology optimization, and the results show that the absolute value of the Zernike coefficient Z4 after optimization is improved by nearly one order of magnitude compared with the value before optimization, and the vibration characteristics of the optimized structure meet the design requirements. The optimization effect is significant, which improves the optical performance of the deformed mirror and provides a new scheme for the design of the deformed mirror structure which has a certain practical value for engineering.
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Dvornichenko, М. V. "AN ESTIMATION OF FREQUENCY AND SPECTRUM OF CHROMOSOMAL ABERRATIONS IN PATIENTS WITH CONNECTIVE TISSUE DYSPLASIA IN CONDITIONS OF BLOOD CELLS CONTACT WITH NANOSTRUCTURED MATERIALS." Bulletin of Siberian Medicine 12, no. 6 (December 28, 2013): 175–81. http://dx.doi.org/10.20538/1682-0363-2013-6-175-181.
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In order to evaluate cytogenetic effect of nanocomposite materials used in traumatology and orthopedics an investigation of chromosomal aberration ins in the culture of lymphocytes short-term contacted with artificial material (nanostructured titanium samples of implants bearing bilateral calcium phosphate coating) in patients with dysplasia of connective tissue (DCT) and osteogenesis imperfecta (OI) has been conducted. A reduction of percent of aberrant cells having single or/and paired chromosomal breaks as compared with spontaneous mutagenesis (without model samples) was revealed under introduced biocompatible composites into blood cell cultures of patients with DCT or OI. Analysis of frequency and spectrum of chromosomal aberrations in blood cells can be considered as potential prognostic criterion and a predictor of implant’s efficacy in the surgical treatment of DCT and OI complications.
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Beklemysheva, Katerina A., Georgiy K. Grigoriev, Nikolay S. Kulberg, Igor B. Petrov, Aleksey V. Vasyukov, and Yuri V. Vassilevski. "Numerical simulation of aberrated medical ultrasound signals." Russian Journal of Numerical Analysis and Mathematical Modelling 33, no. 5 (November 27, 2018): 277–88. http://dx.doi.org/10.1515/rnam-2018-0023.
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Abstract Transcranial ultrasound examination is hampered by the skull which acts as an irregular aberrator of the ultrasound signal. Numerical recovery of the ultrasound field can help in elimination of aberrations induced by the skull. In this paper, we address the simulation of medical phantom scanning through silicon aberrators with wave notching. The numerical model is based on the 2D acoustic equations which are solved by the wavefront construction raytracing method. Numerical B-scan images are compared with experimental B-scan images.
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Bochtler, Tilmann, Ute Hegenbart, Friedrich W. Cremer, Christiane Heiss, Axel Benner, Dirk Hose, Marion Moos, et al. "Evaluation of the cytogenetic aberration pattern in amyloid light chain amyloidosis as compared with monoclonal gammopathy of undetermined significance reveals common pathways of karyotypic instability." Blood 111, no. 9 (May 1, 2008): 4700–4705. http://dx.doi.org/10.1182/blood-2007-11-122101.
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AbstractChromosomal aberrations (CAs) have emerged as important pathogenetic and prognostic factors in plasma cell disorders. Using interphase fluorescence in situ hybridization (FISH) analysis, we evaluated CAs in a series of 75 patients with amyloid light chain amyloidosis (AL) as compared with 127 patients with monoclonal gammopathy of unknown significance (MGUS). We investigated IgH translocations t(11;14), t(4;14), and t(14;16) as well as gains of 1q21, 11q23, and 19q13 and deletions of 8p21, 13q14, and 17p13, detecting at least one CA in 89% of the patients. Translocation t(11;14) was the most frequent aberration in AL, with 47% versus 26% in MGUS (P = .03), and was strongly associated with the lack of an intact immunoglobulin (P < .001), thus contributing to the frequent light chain subtype in AL. Other frequent aberrations in AL included deletion of 13q14 and gain of 1q21, which were shared by MGUS at comparable frequencies. The progression to multiple myeloma (MM) stage I was paralleled by an increased frequency of gain of 1q21 (P = .001) in both groups. Similar branching patterns were observed in an oncogenetic tree model, indicating a common mechanism of underlying karyotypic instability in these plasma cell disorders.
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Yang, Huizhen, Zhen Zhang, and Jian Wu. "Performance Comparison of Wavefront-Sensorless Adaptive Optics Systems by Using of the Focal Plane." International Journal of Optics 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/985351.
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The correction capability and the convergence speed of the wavefront-sensorless adaptive optics (AO) system are compared based on two different system control algorithms, which both use the information of focal plane. The first algorithm is designed through the linear relationship between the second moment of the aberration gradients and the masked far-field intensity distribution and the second is stochastic parallel gradient descent (SPGD), which is the most commonly used algorithm in wavefront-sensorless AO systems. A wavefront-sensorless AO model is established with a 61-element deformable mirror (DM) and a CCD. Performance of the two control algorithms is investigated and compared through correcting different wavefront aberrations. Results show that the correction ability of AO system based on the proposed control algorithm is obviously better than that of AO system based on SPGD algorithm when the wavefront aberrations increase. The time needed by the proposed control algorithm is much less than that of SPGD when the AO system achieves similar correction results. Additionally, the convergence speed of the proposed control algorithm is independent of the turbulence strength while the number of intensity measurements needed by SPGD increases as the turbulence strength magnifies.
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Vaidya, Manjusha, Sandeep Sreerama, Mariana Gaviria, and Kiminobu Sugaya. "Exposure to a Pathological Condition May Be Required for the Cells to Secrete Exosomes Containing mtDNA Aberration." Journal of Nucleic Acids 2022 (March 17, 2022): 1–9. http://dx.doi.org/10.1155/2022/7960198.
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Exosomes, nanovesicles secreted by all cells, carry out intercellular communication by transmitting biologically active cargo comprising DNA, RNA, and proteins. These biomolecules reflect the status of their parent cells and can be altered by pathological conditions. Therefore, the researchers have been investigating differential sequences and quantities of DNA associated with exosomes as valuable biomarkers of diseases. Exosomes carry different types of DNA molecules, including genomic, cytoplasmic, and mitochondrial (mtDNA). The mtDNA aberrations are reported to be a hallmark of diseases involving oxidative stress, such as cancer and neurodegenerative diseases. Establishing robust in vitro models comprising appropriate cell lineages is the first step towards investigating disease-specific anomalies and testing therapeutics. Induced pluripotent stem (iPS) cells from patients with diseases have been used for this purpose since they can differentiate into various cells. The current study investigated mtDNA aberrations in exosomes secreted by primary cancer cells and neural stem cells (NSCs) differentiated from iPS cells. The primary cancer cells were isolated from surgically removed glioblastoma multiforme (GBM) tissue, and the iPS cells were produced from control and Alzheimer’s disease (AD) subjects’ B lymphocytes. We detected aberrations in mtDNA associated with exosomes secreted from GBM cells but not from the NSCs. This result indicates that the cells may not secrete exosomes carrying mtDNA aberration without exposure to a pathological condition. Thus, we may need to consider this fact when we use iPS cell-derived cells as an in vitro disease model.
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Ida, T., and H. Hibino. "Symmetrization of diffraction peak profiles measured with a high-resolution synchrotron X-ray powder diffractometer." Journal of Applied Crystallography 39, no. 1 (January 12, 2006): 90–100. http://dx.doi.org/10.1107/s0021889805040318.
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The asymmetry of diffraction peak profiles observed with a high-resolution synchrotron powder X-ray diffractometer has been successfully removed by a double deconvolution method. In the first step, the asymmetry caused by the axial divergence aberration of the diffractometer is removed by a whole-pattern deconvolution method based on ana prioritheoretical model for the aberration. In the second step, the residual asymmetry, the origin of which can be ascribed to the aberrations of the beamline optics, is also removed by a whole-pattern deconvolution method, based on an empirical model derived from the analysis of experimental diffraction peak profiles of a standard Si powder (NIST SRM640b). The beamline aberration has been modelled by the convolution of a pseudo-Voigt or Voigt function with an exponential distribution function. It has been found that the angular dependence of the asymmetry parameter in the exponential function is almost proportional to tanθ, which supports the idea that the residual asymmetry should be ascribed mainly to the intrinsic asymmetry in the spectroscopic distribution of the source X-ray supplied by the beamline optics of the synchrotron facility. Recently developed procedures of whole-pattern deconvolution have been improved to treat the singularity of the instrumental function in the measured angular range. Formulae for the whole-pattern deconvolution based on the Williamson–Hall-type dependence of the width parameter of the instrumental function have also been developed. The method was applied to the diffraction intensity data of a standard ZnO powder sample (NIST SRM674) measured with a high-resolution powder diffractometer on beamline BL4B2at the Photon Factory. The structure parameters of ZnO were refined from the integrated peak intensities, which were extracted by an individual profile fitting method applying symmetric profile models. The refined structure parameters coincide fairly well with those obtained from single-crystal data.
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Hammer, Anne Sofie Borg, Kristian Juul-Dam, Julie Damgaard Sandahl, Jonas Abrahamsson, Walentyna Balwierz, Audrey Guilmatre, Iren Haltrich, et al. "Hypodiploidy in Childhood Acute Myeloid Leukemia: A Retrospective Cohort Study within the International Berlin-Frankfurt-Münster Study Group." Blood 132, Supplement 1 (November 29, 2018): 1466. http://dx.doi.org/10.1182/blood-2018-99-109988.
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Abstract Background: Despite major improvements in survival, relapse is still a frequent and severe event in pediatric acute myeloid leukemia (AML). Cytogenetic abnormalities represent important predictors of outcome. Improved risk stratification encompassing the identification of novel cytogenetic subsets may allow refinements in treatment strategies and increase survival rates. Hypodiploidy, defined as a modal number (MN) below 46 chromosomes, is associated with an adverse outcome in pediatric acute lymphoblastic leukemia. In childhood AML, the predominant cause of hypodiploidy is loss of a sex chromosome accompanying t(8;21). The most commonly lost autosome is chromosome 7, associated with a poor prognosis. However, other chromosome losses in pediatric AML have not been independently explored. We aimed to investigate the occurrence, genetic characteristics, and prognostic impact of hypodiploidy in childhood AML. Methods: This study was conducted as a retrospective cohort study within the I-BFM-AML framework. Children 0-18 years of age diagnosed with de novo AML between January 2000 to December 2015 and a hypodiploid karyotype were eligible for inclusion. Patients with constitutional hypodiploidy, monosomy 7, composite karyotypes, and t(8;21) with loss of a sex chromosome were excluded. Cytogenetic review was performed according to International System for Human Cytogenetic Nomenclature. Hypodiploidy was considered clonal when occurring in at least three metaphases. The clone with the lowest MN defined the ploidy level. The log-rank test was applied for estimating difference in survival. Considering allografting in first complete remission (CR1) as a time-dependent event, the effect of stem cell transplantation (SCT) on overall survival (OS) was estimated by the Mantel-Byar method. Multivariate analyses included sex, complex karyotype (≥3 non-recurrent aberrations), FLT3-ITD mutation status, and white blood cell count as covariates. As all patients with FLT3-ITD mutations had same MN (MN=45) leading to a skewed imputation model, multiple imputation was not performed, and multivariate analyses included complete cases only (n=54). Results: Hypodiploidy was detected in 81/6,409 patients with full karyotyping from 14 collaborative study groups, yielding a frequency of 1.2% in childhood AML. The cohort displayed a balanced sex distribution (male/female: 42/39) and a median age of 6 (range: 0-17). MNs 45 (n=66), 44 (n=10) and 43 (n=5) were observed. No patient had MN below 43. Eight patients (9.8%) had chromosome loss as the only aberration. Forty-eight patients (59%) had a complex karyotype. Core-binding factor abnormalities were observed in three patients (3.7%). Four patients harbored FLT3-ITD mutations (9.3%, 54 tested). Median follow-time for patients alive was 4.5 years (range: 0.2-15.3). Five-year event-free survival (EFS) and OS were 34% (CI 95%: 23% - 45%) and 52% (CI 95%: 40% - 63%), respectively. Cumulative incidence of relapse was 50% with a median time-to-relapse of 0.8 years. Twelve out of 38 relapsed children (32%) were alive at the end of follow-up. Children with MN≤44 (n=15) had lower EFS (21%, CI 95%: 4% - 46%) and OS (33%, CI 95%: 10% - 59%) than children with MN=45 (n=66, EFS: 37%, CI 95%: 24% - 49%, OS: 56%, CI 95%: 42% - 68%). Crude hazard ratios (HR) for MN≤44 vs MN=45 were 1.8 (p=0.08) for EFS and 1.9 (p=0.1) for OS. After adjustment HRs increased to 4.9 (p=0.001) and 6.1 (p=0.003), respectively. Loss of chromosome Y (n=12) displayed a non-significant superior survival (EFS: 58%, OS: 75%). Poor survival rates were especially observed in monosomy 9 (n=11, EFS: 14%, OS 15%), 10 (n=5, EFS: 20%, OS: 20%), and 16 (n=5, EFS: 25%, OS: 25%), although not reaching statistical significance. Allogenic SCT did not offer any advantage in survival. For children receiving SCT in CR1 (n=18), crude HR for OS was 1.4, p=0.39. Multivariate analysis showed HR for OS at 1.5, p=0.42. Exclusion of children not reaching CR1 (n=7) did not significantly change HRs. This large international study reveals that hypodiploidy is rare in pediatric AML. Children with loss of chromosome 9, 10, or 16 all displayed unfavorable survival rates, whereas loss of chromosome Y did not have influence on prognosis. SCT in CR1 did not improve survival. Our results suggest that modal number has an impact on outcome and may be important for risk stratification. Disclosures No relevant conflicts of interest to declare.
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Ahmadi, Kavan, and Artur Carnicer. "Estimation of Zernike polynomials for a highly focused electromagnetic field using polarimetric mapping images and neural networks." Journal of Physics: Conference Series 2407, no. 1 (December 1, 2022): 012002. http://dx.doi.org/10.1088/1742-6596/2407/1/012002.
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Abstract In this communication, we present a method to estimate the aberrated wavefront at the focal plane of a vectorial diffraction system. In contrast to the phase, the polarization state of optical fields is simply measurable. In this regard, we introduce an alternative approach for determining the aberration of the wavefront using polarimetric information. The method is based on training a convolutional neural network using a large set of polarimetric mapping images obtained by simulating the propagation of aberrated wavefronts through a high-NA microscope objective; then, the coefficients of the Zernike polynomials could be recovered after interrogating the trained network. On the one hand, our approach aims to eliminate the necessity of phase retrieval for wavefront sensing applications, provided the beam used is known. On the other hand, the approach might be applied for calibrating the complex optical system suffering from aberrations. As proof of concept, we use a radially polarized Gaussian-like beam multiplied by a phase term that describes the wavefront aberration. The training dataset is produced by using Zernike polynomials with random coefficients. Two thousand random combinations of polynomial coefficients are simulated. For each one, the Stokes parameters are calculated to introduce a polarimetric mapping image as the input of a neural network model designed and trained for predicting the polynomial coefficients. The accuracy of the neural network model is tested by predicting an unseen dataset (test dataset) with a high success rate.
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Heilig, Christoph E., Harald Löffler, Anna Jauch, Ulrich Mahlknecht, Anthony Ho, and Alwin Krämer. "Chromosomal Instability Correlates with Poor Outcome in Patients with Myelodysplastic Syndromes." Blood 112, no. 11 (November 16, 2008): 5077. http://dx.doi.org/10.1182/blood.v112.11.5077.5077.
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Abstract Introduction: One of the hallmarks of human cancer is genomic instability, most often prevalent as chromosomal instability (CIN). CIN is defined by an elevated frequency of the occurrence of novel chromosomal aberrations and therefore, in contrast to aneuploidy, represents a rate rather than a state of genomic aberration. CIN has not only been implicated in the generation of aneuploidy, but also has been shown to play a pivotal role in both early malignant transformation and tumor progression. However, data on the presence and the extent of CIN in a defined population of primary malignant cells in different stages of disease are lacking. Myelodysplastic syndromes (MDS) are clonal stem-cell disorders characterized by ineffective hematopoiesis in one or more hematopoietic lineages and a high propensity for transformation into acute myeloid leukemia (AML). Furthermore, recurrent chromosomal aberrations are shared by both MDS and AML. Given their premalignant state, their frequent progression to AML, and their origin in an easy accessible stem-cell compartment, we considered MDS as a suitable model to study the role of CIN in tumor initiation and progression. Methods: We isolated CD34-positive cells from 18 patients with MDS, 30 patients with AML, 9 healthy controls, and 8 control patients with malignancies not involving the bone marrow. Patient samples were first objected to Ficoll density separation. Next, the CD34-positive cells were magnetically sorted (MACS) using CD34-microbeads. Purity of the sorted cells was controlled by flow cytometry (FACS) and constantly was greater 85%. Fluorescence in situ hybridization (FISH) was then performed, hybridizing centromeric probes for chromosomes 1, 6, 7, and 8, and subtelomeric probes for chromosomes 6 and 8 to the CD34-positive cells. Finally, the cell-to-cell variability of the chromosome content as well as the extent of structural instability was quantified by determining the modal signal number for each FISH probe and the median percentage of cells differing thereof. Results: In this study, we were able to identify a group of patients with numerical CIN values that were elevated more than two standard deviations relative to the mean of healthy control subjects (5.8% + 3.0%). This group of patients with elevated CIN values had a worse outcome as compared to the patients with normal CIN values: All three patients in the ‘high CIN’ group reached the endpoint, defined as progression to AML (two patients) or death (one patient), within 4.9, 10.2, and 12.3 months after sample collection, respectively, whereas among the remaining 15 patients with normal CIN values there was only one case of death (3.9 months after sample collection) and one patient with progression to AML (20.1 months after sample collection) at a median follow-up of 14.2 months (Figure 1). Furthermore, we were able to demonstrate an increase of CIN preceding the transformation to AML in one patient with MDS RAEB-2 over the course of five months. Eventually, our results neither did indicate a role for structural CIN in MDS disease progression, nor did they show a difference between clinically defined subgroups, indicating that CIN may represent a novel prognostic marker independent of the conventional classification criteria for MDS. Conclusion: Our data indicate a possible role for numerical CIN in the progression of MDS to AML. Moreover, a CD34-positive cell-specific increase of CIN might be a predictor for the subsequent disease progression to AML. Therefore, the quantification of CIN in hematopoietic progenitor cells might be valuable for identifying patients with high-risk MDS more reliably. Figure 1: Kaplan-Meier-Plot comparing the outcome of MDS patients with elevated CIN values (red dashed line) and normal CIN values (blue solid line). After a median follow-up of 14.2 months, all but two patients in the “low CIN” group had stable disease, whereas all three patients with elevated CIN values reached the endpoint, defined as progression to AML or death. Figure 1:. Kaplan-Meier-Plot comparing the outcome of MDS patients with elevated CIN values (red dashed line) and normal CIN values (blue solid line). After a median follow-up of 14.2 months, all but two patients in the “low CIN” group had stable disease, whereas all three patients with elevated CIN values reached the endpoint, defined as progression to AML or death.
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Ribeiro, T. P., T. R. Sousa, A. S. Arruda, N. Peixoto, P. J. Gonçalves, and L. M. Almeida. "Evaluation of cytotoxicity and genotoxicity of Hancornia speciosa latex in Allium cepa root model." Brazilian Journal of Biology 76, no. 1 (January 22, 2016): 245–49. http://dx.doi.org/10.1590/1519-6984.20114.
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Abstract The latex obtained from Hancornia speciosa Gomes (Mangabeira tree) is widely used in traditional medicine to treat a variety of diseases, including diarrhea, ulcer, gastritis, tuberculosis, acne and warts. In this study, the cytotoxicity and genotoxicity effects of H. speciosa latex on the root meristem cells of Allium cepa were examined. Onion bulbs were exposed to different concentrations of latex and then submitted to microscopic analysis using Giemsa stain. Water was used as a negative control and sodium azide as a positive control. The results showed that, under the testing conditions, the mitotic index (MI) of the onion roots submitted to latex treatment did not differ significantly from the negative control, which suggests that the latex is not cytotoxic. Low incidence of chromosome aberrations in the cells treated with H. speciosa latex was also observed, indicating that the latex does not have genotoxic effect either. The MI and the chromosome aberration frequency responded to the latex concentration, requiring more studies to evaluate the dosage effect on genotoxicity. The results indicate that in tested concentrations H. speciosa latex is probably not harmful to human health and may be potentially used in medicine.
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Leiva, Orly, Olesya Baker, Andrew M. Brunner, Hanny Al-Samkari, Rebecca Karp Leaf, Rachel P. Rosovsky, Amir T. Fathi, et al. "Rates of Thrombotic Events in Hypereosinophilic Syndrome and the Effect of Molecular Aberrations in Thrombotic Risk." Blood 136, Supplement 1 (November 5, 2020): 14. http://dx.doi.org/10.1182/blood-2020-137311.
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Background: Idiopathic hypereosinophilia and hypereosinophilic syndrome (HES) comprise a rare, heterogeneous group of hematologic disorders characterized by the overproduction of eosinophils leading to tissue eosinophilic infiltration and damage. Hypereosinophilia can be primary - due to a clonal or malignant process - or secondary to a non-clonal process. Primary eosinophilia can be accompanied by clonal markers, such as in myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA/B, FGFR1 or PCM1-JAK2, genetic mutations or chromosomal abnormalities leading to a diagnosis of chronic eosinophilic leukemia. Without easily identifiable clonal markers, a diagnosis of idiopathic HES is made after secondary causes are excluded. Thrombotic complications in clonal eosinophilic disorders have been described in case reports but the prevalence of thrombosis has not been extensively studied. We hypothesized that HES is associated with an increased thrombotic risk compared to the general population. Additionally, given the known increased thrombotic risk in patients with clonal hematopoiesis of indeterminate potential, we also hypothesized that the risk of thrombosis is greatest in HES patients with evidence of an underlying clonal process. Methods: Using an institutional database, we retrospectively analyzed 44 patients with HES who had undergone molecular testing with a DNA based next generation sequencing (NGS) assay (Heme SnapShot) and an RNA based NGS assay (Heme fusion) as part of their work up for HES at Massachusetts General Hospital from 2016 to 2020. Patients with secondary eosinophilia were excluded. We used Fisher's exact test to compare rates of thrombotic events or death between patients with and without molecular aberration. Relative risk and corresponding 95% CI was estimated by fitting a log-binomial regression model. Results: Among the 44 patients analyzed, 16 (36.4%) had a molecular aberration detected on NGS. Of the patients with molecular aberrations detected, 4 (25%) had PGFRA, PGFRB, or FGFR1 fusions. Other pathogenic mutations were as follows - 1 (6.3%) JAK2 mutation, 3 (18.8%) TET2, 1 (6.3%) DNMT3A and 9 (56.4%) had mutations in other genes. White blood cell count, absolute eosinophil count, hematocrit, platelet count, tryptase and vitamin B12 levels at diagnosis of HES were similar between the two groups. After a median follow-up time of 29 months (IQR 19.3, 52), 9 (20.5%) of all HES patients had a thrombotic event after diagnosis of HES (4 venous and 5 arterial) with a median time to first thrombotic event of 14.0 months (IQR 3.5, 28.0). HES patients with a molecular aberration had increased number of thrombotic events compared to HES patients with no molecular aberrations, 37.5% versus 10.7% respectively (p = 0.053, risk ratio 3.5, 95% CI 1.01 - 12.12). Three patients with molecular aberrations died versus 1 patient with no molecular aberrations (p = 0.129, risk ratio 5.25, 95% CI 0.59 - 46.36). Among patients with at least 12 months of follow-up (n = 40, 14 with and 26 without molecular aberrations), the one-year cumulative incidence of thrombotic events was 42.9% in patients with molecular aberrations vs 11.5% without (p = 0.044, RR 3.7 95% CI 1.2-12.0). HES patients who had thrombotic events had an increased risk of death compared to those without thrombotic events (p = 0.0226, RR 11.7, 95% CI 1.8 - 75.2). Conclusions: Thrombotic complications are common in the current study of patients with HES and are associated with an increased risk of death. Although our patient cohort was small, presence of molecular aberrations had increased rates of thrombotic events and mortality, suggesting an area of further study including possible therapeutic trials. Figure 1 Disclosures Brunner: Takeda: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; AstraZeneca: Research Funding; Forty-Seven Inc: Membership on an entity's Board of Directors or advisory committees; Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees. Al-Samkari:Argenx: Consultancy; Amgen: Research Funding; Dova: Consultancy, Research Funding; Agios: Consultancy, Research Funding; Rigel: Consultancy. Rosovsky:Bristol-Myers Squibb, Janssen: Research Funding; Bristol-Myers Squibb, Dova, Janssen, Portola: Consultancy. Fathi:PTC Therapeutics: Consultancy; Takeda: Consultancy; TrovaGene: Consultancy; Amgen: Consultancy; Bristol-Myers Squibb: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Astellas: Consultancy; Novartis: Consultancy; NewLink Genetics: Consultancy, Honoraria; Daiichi Sankyo: Consultancy; Forty Seven: Consultancy; Jazz: Consultancy, Honoraria; Kite: Consultancy, Honoraria; Trillium: Consultancy; Seattle Genetics: Consultancy, Research Funding; Pfizer: Consultancy; Kura: Consultancy; Boston Biomedical: Consultancy; Blue Print Oncology: Consultancy; AbbVie: Consultancy; Agios: Consultancy, Research Funding; Amphivena: Consultancy, Honoraria. Weitzman:Abbvie: Consultancy. Hobbs:Incyte: Research Funding; Bayer: Research Funding; Novartis: Honoraria; Celgene/BMS: Honoraria; Merck: Research Funding; Constellation: Honoraria, Research Funding; Jazz: Honoraria.
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Huang, Chih Chien, Du Jou Huang, Yu Ju Chen, Shu Ming T. Wang, and Rey Chue Hwang. "The Identification of TP Chromatic Aberration by Using Nearly Equivalent NN Model." Advanced Materials Research 211-212 (February 2011): 275–79. http://dx.doi.org/10.4028/www.scientific.net/amr.211-212.275.
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This paper presents the chromatic aberration identification of touch panel (TP) decoration film by using nearly equivalent neural network (NN) model. This model is expected to adequately catch the complex relationship between the chromatic aberration and its possible influencing factors during the evaporation process of TP decoration film. Then, an intelligent estimator for the chromatic aberration of TP film could be developed automatically. Based on this estimator, the technician could set the control parameters of evaporation process in advance and make the quality of chromatic aberration of TP could meet the customer’s required.
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Yang, Mingyang, Xuewu Fan, Yuming Wang, and Hui Zhao. "Analysis, Simulations, and Experiments for Far-Field Fourier Ptychography Imaging Using Active Coherent Synthetic-Aperture." Applied Sciences 12, no. 4 (February 20, 2022): 2197. http://dx.doi.org/10.3390/app12042197.
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Fourier ptychography (FP) is a powerful phase retrieval method that can be used to reconstruct missing high-frequency details and high-space-bandwidth products in microscopy. In this study, we further advanced the application of FP in microscopic imaging to the field of macroscopic far-field imaging, incorporating camera scanning for spatial resolution improvement. First, on the basis of the Fraunhofer diffraction mechanism and the transmission imaging model, we found the analysis of the associated theoretical fundamentals via simulations and experiments to be crucially relevant to the far-field of FP imaging. Second, we built an experimental device with long-distance imaging and experimentally demonstrated the relationship between the spectrum overlap ratio and the reconstructed high-resolution image. The simulation and experimental results showed that an overlap ratio higher than 50% had a good reconstruction effect. Third, camera scanning was used to obtain low-resolution intensity images in this study, for which the scanning range was wide and spherical wave illumination was satisfied, and therefore different positions corresponded to different aberrations of low-resolution intensity images, and even different positions of the same image had aberration differences, leading to inconsistencies in the aberrations of different images. Therefore, in the reconstruction process, we further overcame the effect of the inconsistency of aberrations of different images using the partition reconstruction method, which involves cutting the image into smaller parts for reconstruction. Finally, with the proposed partition reconstruction algorithm, we were able to resolve 40 μm line width of GBA1 resolution object and obtain a spatial resolution gain of 4× with a working distance of 2 m.
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Vigan, A., M. N’Diaye, K. Dohlen, J. F. Sauvage, J. Milli, G. Zins, C. Petit, et al. "Calibration of quasi-static aberrations in exoplanet direct-imaging instruments with a Zernike phase-mask sensor." Astronomy & Astrophysics 629 (August 26, 2019): A11. http://dx.doi.org/10.1051/0004-6361/201935889.
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Second-generation exoplanet imagers using extreme adaptive optics (ExAO) and coronagraphy have demonstrated their great potential for studying close circumstellar environments and for detecting new companions and helping to understand their physical properties. However, at very small angular separation, their performance in contrast is limited by several factors: diffraction by the complex telescope pupil (central obscuration and spiders) not perfectly canceled by the coronagraph, residual dynamic wavefront errors, chromatic wavefront errors, and wavefront errors resulting from noncommon path aberrations (NCPAs). These latter are differential aberrations between the visible wavefront sensing path of the ExAO system and the near-infrared science path in which the coronagraph is located. In a previous work, we demonstrated the use of a Zernike wavefront sensor called ZELDA for sensing NCPAs in the VLT/SPHERE exoplanet imager and their compensation with the high-order deformable mirror of the instrument. These early tests on the internal light source led to encouraging results for the attenuation of the quasi-static speckles at very small separation. In the present work, we move to the next step with the on-sky validation of NCPA compensation with ZELDA. With an improved procedure for the compensation of NCPAs, we start by reproducing previous results on the internal source. We show that the amount of aberration integrated between 1 and 15 cycles/pupil (c/p) is decreased by a factor of approximately five, which translates into a gain in raw contrast of between 2 and 3 at separations below 300 mas. On sky, we demonstrate that NCPA compensation works in closed loop, leading to an attenuation of the amount of aberration by a factor of approximately two. However, we identify a loss of sensitivity for the sensor that is only partly explained by the difference in Strehl ratio between the internal and on-sky measurements. Our simulations show that the impact of ExAO residuals on ZELDA measurements is negligible for integration times beyond a few tenths of a second. Coronagraphic imaging on sky is improved in raw contrast by a factor of 2.5 at most in the ExAO-corrected region. We use coronagraphic image reconstruction based on a detailed model of the instrument to demonstrate that both internal and on-sky raw contrasts can be precisely explained, and we establish that the observed performance after NCPA compensation is no longer limited by an improper compensation for aberration but by the current apodized-pupil Lyot coronagraph design. We finally conclude that a coronagraph upgrade combined to a proper NCPA compensation scheme could easily bring a gain in raw contrast of a factor of two to three below 200 mas.
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Pajusalu, Mihkel, Iaroslav Iakubivskyi, Gabriel Jörg Schwarzkopf, Olli Knuuttila, Timo Väisänen, Maximilian Bührer, Mario F. Palos, et al. "SISPO: Space Imaging Simulator for Proximity Operations." PLOS ONE 17, no. 3 (March 4, 2022): e0263882. http://dx.doi.org/10.1371/journal.pone.0263882.
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This paper describes the architecture and demonstrates the capabilities of a newly developed, physically-based imaging simulator environment called SISPO, developed for small solar system body fly-by and terrestrial planet surface mission simulations. The image simulator utilises the open-source 3-D visualisation system Blender and its Cycles rendering engine, which supports physically based rendering capabilities and procedural micropolygon displacement texture generation. The simulator concentrates on realistic surface rendering and has supplementary models to produce realistic dust- and gas-environment optical models for comets and active asteroids. The framework also includes tools to simulate the most common image aberrations, such as tangential and sagittal astigmatism, internal and external comatic aberration, and simple geometric distortions. The model framework’s primary objective is to support small-body space mission design by allowing better simulations for characterisation of imaging instrument performance, assisting mission planning, and developing computer-vision algorithms. SISPO allows the simulation of trajectories, light parameters and camera’s intrinsic parameters.
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Mozaffarzadeh, Moein, Martin D. Verweij, Nico de Jong, and Guillaume Renaud. "Comparison of Phase-Screen and Geometry-Based Phase Aberration Correction Techniques for Real-Time Transcranial Ultrasound Imaging." Applied Sciences 12, no. 19 (October 10, 2022): 10183. http://dx.doi.org/10.3390/app121910183.
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While transcranial ultrasound imaging is a promising diagnostic modality, it is still hindered due to phase aberration and multiple scattering caused by the skull. In this paper, we compare near-field phase-screen modeling (PS) to a geometry-based phase aberration correction technique (GB) when an ultrafast imaging sequence (five plane waves tilted from −15 to +15 degrees in the cutaneous tissue layer) is used for data acquisition. With simulation data, the aberration profile (AP) of two aberrator models (flat and realistic temporal bone) was estimated in five isoplanatic patches, while the wave-speed of the brain tissue surrounding the point targets was either modeled homogeneously (ideal) or slightly heterogeneously to generate speckle (for mimicking a more realistic brain tissue). For the experiment, a phased array P4-1 transducer was used to image a wire phantom; a 4.2-mm-thick bone-mimicking plate was placed in front of the probe. The AP of the plate was estimated in three isoplanatic patches. The numerical results indicate that, while all the scatterers are detectable in the image reconstructed by the GB method, many scatterers are not detected with the PS method when the dataset used for AP estimation is generated with a realistic bone model and heterogeneous brain tissue. The experimental results show that the GB method increases the signal-to-clutter ratio (SCR) by 7.5 dB and 6.5 dB compared to the PS and conventional reconstruction methods, respectively. The GB method reduces the axial/lateral localization error by 1.97/0.66 mm and 2.08/0.7 mm compared to the PS method and conventional reconstruction, respectively. The lateral spatial resolution (full-width-half-maximum) is also improved by 0.1 mm and 1.06 mm compared to the PS method and conventional reconstruction, respectively. Our comparison study suggests that GB aberration correction outperforms the PS method when an ultrafast multi-angle plane wave sequence is used for transcranial imaging with a single transducer.