84 results on '"Sagi E"'
Search Results
2. The Multi-needle Langmuir Probe Instrument for QB50 Mission: Case Studies of Ex-Alta 1 and Hoopoe Satellites
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Hoang, H., Røed, K., Bekkeng, T. A., Moen, J. I., Clausen, L. B. N., Trondsen, E., Lybekk, B., Strøm, H., Bang-Hauge, D. M., Pedersen, A., Nokes, C. D. A., Cupido, C., Mann, I. R., Ariel, M., Portnoy, D., and Sagi, E.
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- 2019
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3. Aims and Means of Developing the West Bank / מטרות ואמצעים לפיתוח הגדה המערבית
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שגיא, אליהו and Sagi, E.
- Published
- 1972
4. Computer Vision for Recognition of Materials and Vessels in Chemistry Lab Settings and the Vector-LabPics Data Set
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Sagi Eppel, Haoping Xu, Mor Bismuth, and Alan Aspuru-Guzik
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Chemistry ,QD1-999 - Published
- 2020
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5. Voluntary silence: Israeli media self-censorship during the Second Lebanon War
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Sagi Elbaz and Daniel Bar-Tal
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Self-Censorship ,Conflict ,Elites ,Narratives ,Second Lebanon War ,Psychology ,BF1-990 ,Sociology (General) ,HM401-1281 - Abstract
This article describes the characteristics of self-censorship in general, specifically in mass media, with regard to narratives of political violence, including motivations for and effects of practicing self-censorship. It first presents a broad theoretical conceptualization of self-censorship, and then focuses on its practice in media. The case study examined the representation of The Second Lebanon War in the Israeli national media. The authors carried out content analysis and in-depth interviews with former and current journalists in order to investigate one of the reasons for the dominance of the hegemonic narrative in the media – namely, self-censorship. Indeed, the analysis revealed widespread use of self-censorship by Israeli journalists, their motivations for practicing it, and the effects of its use on the society.
- Published
- 2019
6. Individual and Combined Effects of Paternal Deprivation and Developmental Exposure to Firemaster 550 on Socio-Emotional Behavior in Prairie Voles
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Sagi Enicole A. Gillera, William P. Marinello, Mason A. Nelson, Brian M. Horman, and Heather B. Patisaul
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endocrine disruptors ,flame retardants ,sexual differentiation ,pair bond ,Chemical technology ,TP1-1185 - Abstract
The prevalence of neurodevelopmental disorders (NDDs) is rapidly rising, suggesting a confluence of environmental factors that are likely contributing, including developmental exposure to environmental contaminants. Unfortunately, chemical exposures and social stressors frequently occur simultaneously in many communities, yet very few studies have sought to establish the combined effects on neurodevelopment or behavior. Social deficits are common to many NDDs, and we and others have shown that exposure to the chemical flame retardant mixture, Firemaster 550 (FM 550), or paternal deprivation impairs social behavior and neural function. Here, we used a spontaneously prosocial animal model, the prairie vole (Microtus ochrogaster), to explore the effects of perinatal chemical (FM 550) exposure alone or in combination with an early life stressor (paternal absence) on prosocial behavior. Dams were exposed to vehicle (sesame oil) or 1000 µg FM 550 orally via food treats from conception through weaning and the paternal absence groups were generated by removing the sires the day after birth. Adult offspring of both sexes were then subjected to open-field, sociability, and a partner preference test. Paternal deprivation (PD)-related effects included increased anxiety, decreased sociability, and impaired pair-bonding in both sexes. FM 550 effects include heightened anxiety and partner preference in females but reduced partner preference in males. The combination of FM 550 exposure and PD did not exacerbate any behaviors in either sex except for distance traveled by females in the partner preference test and, to a lesser extent, time spent with, and the number of visits to the non-social stimulus by males in the sociability test. FM 550 ameliorated the impacts of parental deprivation on partner preference behaviors in both sexes. This study is significant because it provides evidence that chemical and social stressors can have unique behavioral effects that differ by sex but may not produce worse outcomes in combination.
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- 2022
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7. Reimplantation of hybrid cochlear implant users with a full-length electrode after loss of residual hearing.
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Fitzgerald MB, Sagi E, Jackson M, Shapiro WH, Roland JT Jr, Waltzman SB, Svirsky MA, Fitzgerald, Matthew B, Sagi, Elad, Jackson, Michael, Shapiro, William H, Roland, J Thomas Jr, Waltzman, Susan B, and Svirsky, Mario A
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- 2008
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8. What matched comparisons can and cannot tell us: the case of cochlear implants.
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Sagi E, Fitzgerald MB, and Svirsky MA
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- 2007
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9. Topical treatment of acne vulgaris with a combination of erythromycin 2% plus bifonazole 1% once daily compared to erythromycin 2% alone twice daily: a randomized, double-blind, controlled, clinical study.
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Sagi, E, Vardy, D, Shemer, A, Laver, Z, Amichi, B, Shiri, J, Zuckerman, F, Oren, I, Friedman, R, and David, M
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- *
ACNE , *COMBINATION drug therapy , *ERYTHROMYCIN , *BIFONAZOLE , *SKIN disease treatment , *DRUG efficacy - Abstract
BACKGROUND: The mainstay of mild to moderate acne treatment is topical antibiotics. A new combination of 2% erythromycin and 1% bifonazole was tested in a double-blind trial against erythromycin alone. METHODS: A total of 207 acne patients were recruited into the study and 157 (76%) completed the full trial protocol of 12 weeks of treatment. In all, 74 patients applied the combination solution (erythromycin + bifonazole) once a day and 83 patients applied erythromycin solution twice a day. Outcome parameters measured were lesion-count (open and closed comedones, papules and pustules) and acne grading using the Cook's acne scale, carried out at the initial visit, and at the 4, 8 and 12-week follow-up visits. RESULTS: Both treatment groups improved significantly over baseline and showed continuous improvement throughout the trial, with the erythromycin + bifonazole group showing better improvement than the erythromycin group. At the end of 12 weeks, open comedones, closed comedones, papules and pustules were reduced by 57%, 61%, 73% and 83% respectively in the erythromycin + bifonazole group, compared to 47%, 60%, 61% and 72% in the erythromycin group (P-values of 0.04, 0.007, 0.0017 and 0.056, respectively). Acne grading improved by 44.8% in the erythromycin + bifonazole group compared to a 34.7% improvement in the erythromycin group (P-values of 0.047). Transient local adverse effects occurred in both groups leading to five patients dropping out, four of them from the combination group. CONCLUSION: Topical treatment of acne with a combination of erythromycin 2% and bifonazole 1% once daily is a safe and effective treatment that has a modest but significant advantage over treatment with erythromycin 2% alone twice daily. (J Dermatol Treat (2000) 11: 247-251). [ABSTRACT FROM AUTHOR]
- Published
- 2000
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10. The use of doxycycline and tetracycline in ocular rosacea.
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Fruchtpery, J. and Sagi, E.
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- 1993
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11. The Sagi test in pregnancy.
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Mackenzie, Locke L., Sagi, Eugene S., Hammond, Cuyler E., MACKENZIE, L L, SAGI, E S, and HAMMOND, E C
- Published
- 1959
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12. Idiopathic apnoea of prematurity treated with doxapram and aminophylline.
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SAGI, E., EYAL, F., ALPAN, G., PATZ, D., and ARAD, I.
- Abstract
Doxapram infusion was given to five preterm infants in whom therapeutic concentrations of theophylline had failed to control episodes of apnoea. Doxapram successfully controlled the apnoea, the arterial blood PCO2 value decreased significantly, and no side effects were reported. [ABSTRACT FROM AUTHOR]
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- 1984
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13. Necrotising enterocolitis in the very low birthweight infant: expressed breast milk feeding compared with parenteral feeding.
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EYAL, F., SAGI, E., ARAD, I., and AVITAL, A.
- Abstract
The incidence of necrotising enterocolitis (NEC) in very low birthweight infants (VLBW less than or equal to 1500 g) was reduced by the delayed onset of enteral feeding. Eight (18%) out of 44 VLBW infants who were in hospital during the first year of the study developed NEC. During the next 12 months 85 similar infants were initially fed by parenteral nutrition only, and then from age 14-21 days with infant formula. During the second year only 3 (3%) patients developed NEC. There were no other relevant changes in management. Throughout the entire study, the onset of NEC in each infant in whom it occurred was after the start of enteral feeding. We recommend avoiding enteral feeding in VLBW infants during the period that they are particularly vulnerable--namely the first 2 or 3 weeks of life. [ABSTRACT FROM AUTHOR]
- Published
- 1982
14. Seasonal Variation of UV Radiation at the Dead Sea.
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Leibovici, V., Sagi, E., Siladji, S., Greiter, J.C., Greiter, F., and Holubar, K.
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- 1987
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15. Exchange transfusion in newborns via a peripheral artery and vein.
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Sagi, F., Eyal, F., Armon, Y., Arad, I., Robinson, M., and Sagi, E
- Abstract
Exchange transfusion using a peripheral artery and vein was carried out 18 times in 17 newborn infants. The arteries use to withdraw blood were the radial [13], the ulnar [3] an the posterior tibial [2]. Infusion of blood was carried out simultaneously through a peripheral vein. There was no mortality or morbidity directly associated with the procedure. We recommend this technique for exchange transfusion in general, and especially in the very ill newborn. [ABSTRACT FROM AUTHOR]
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- 1981
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16. Ultrasonic guidance of suprapubic aspiration in infants.
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Sagi, Ephraim F., Alpan, Gad, Eyal, Fabian G., Arad, Ilan, Peleg, Ofra, Sagi, E F, Alpan, G, Eyal, F G, Arad, I, and Peleg, O
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- 1983
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17. Doxapram in the treatment of idiopathic apnea of prematurity unresponsive to aminophylline
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Alpan, G., Eyal, F., Sagi, E., Springer, C., Patz, D., and Goder, K.
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- 1984
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18. A level adjusted cochlear frequency-to-place map for estimating tonotopic frequency mismatch with a cochlear implant.
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Sagi E and Svirsky MA
- Abstract
Objectives: To provide a level-adjusted correction to the current standard relating anatomical cochlear place to characteristic frequency in humans, and to re-evaluate anatomical frequency mismatch in cochlear implant (CI) recipients considering this correction. It is hypothesized that a level-adjusted place-frequency function may represent a more accurate tonotopic benchmark for CIs in comparison to the current standard., Design: The present analytical study compiled data from fifteen previous animal studies that reported iso-intensity responses from cochlear structures at different stimulation levels. Extracted outcome measures were characteristic frequencies and centroid-based best frequencies at 70 dB SPL input from 47 specimens spanning a broad range of cochlear locations. A simple relationship was used to transform these measures to human estimates of characteristic and best frequencies, and non-linear regression was applied to these estimates to determine how the standard human place-frequency function should be adjusted to reflect best frequency rather than characteristic frequency. The proposed level-adjusted correction was then compared to average place-frequency positions of commonly used CI devices when programmed with clinical settings., Results: The present study showed that the best frequency at 70 dB SPL (BF70) tends to shift away from characteristic frequency (CF). The amount of shift was statistically significant (signed-rank test z = 5.143, p < 0.001), but the amount and direction of shift depended on cochlear location. At cochlear locations up to 600° from the base, BF70 shifted downwards in frequency relative to CF by about 4 semitones on average. Beyond 600° from the base, BF70 shifted upwards in frequency relative to CF by about 6 semitones on average. In terms of spread (90% prediction interval), the amount of shift between CF and BF70 varied from relatively no shift to nearly an octave of shift. With the new level-adjusted frequency-place function, the amount of anatomical frequency mismatch for devices programmed with standard of care settings is less extreme than originally thought, and may be nonexistent for all but the most apical electrodes., Conclusions: The present study validates the current standard for relating cochlear place to characteristic frequency, and introduces a level-adjusted correction for how best frequency shifts away from characteristic frequency at moderately loud stimulation levels. This correction may represent a more accurate tonotopic reference for CIs. To the extent that it does, its implementation may potentially enhance perceptual accommodation and speech understanding in CI users, thereby improving CI outcomes and contributing to advancements in the programming and clinical management of CIs.
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- 2024
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19. Caught Red-Handed.
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Wiener-Well Y, Levin PD, Sagi E, Ben-Chetrit E, and Ben-Chetrit E
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- Diagnosis, Differential, Female, Humans, Middle Aged, COVID-19 diagnosis, Hand Dermatoses virology, Systemic Inflammatory Response Syndrome diagnosis
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- 2022
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20. Visualization of Speech Perception Analysis via Phoneme Alignment: A Pilot Study.
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Ratnanather JT, Wang LC, Bae SH, O'Neill ER, Sagi E, and Tward DJ
- Abstract
Objective: Speech tests assess the ability of people with hearing loss to comprehend speech with a hearing aid or cochlear implant. The tests are usually at the word or sentence level. However, few tests analyze errors at the phoneme level. So, there is a need for an automated program to visualize in real time the accuracy of phonemes in these tests. Method: The program reads in stimulus-response pairs and obtains their phonemic representations from an open-source digital pronouncing dictionary. The stimulus phonemes are aligned with the response phonemes via a modification of the Levenshtein Minimum Edit Distance algorithm. Alignment is achieved via dynamic programming with modified costs based on phonological features for insertion, deletions and substitutions. The accuracy for each phoneme is based on the F1-score. Accuracy is visualized with respect to place and manner (consonants) or height (vowels). Confusion matrices for the phonemes are used in an information transfer analysis of ten phonological features. A histogram of the information transfer for the features over a frequency-like range is presented as a phonemegram. Results: The program was applied to two datasets. One consisted of test data at the sentence and word levels. Stimulus-response sentence pairs from six volunteers with different degrees of hearing loss and modes of amplification were analyzed. Four volunteers listened to sentences from a mobile auditory training app while two listened to sentences from a clinical speech test. Stimulus-response word pairs from three lists were also analyzed. The other dataset consisted of published stimulus-response pairs from experiments of 31 participants with cochlear implants listening to 400 Basic English Lexicon sentences via different talkers at four different SNR levels. In all cases, visualization was obtained in real time. Analysis of 12,400 actual and random pairs showed that the program was robust to the nature of the pairs. Conclusion: It is possible to automate the alignment of phonemes extracted from stimulus-response pairs from speech tests in real time. The alignment then makes it possible to visualize the accuracy of responses via phonological features in two ways. Such visualization of phoneme alignment and accuracy could aid clinicians and scientists., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Ratnanather, Wang, Bae, O'Neill, Sagi and Tward.)
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- 2022
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21. Valid Acoustic Models of Cochlear Implants: One Size Does Not Fit All.
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Svirsky MA, Capach NH, Neukam JD, Azadpour M, Sagi E, Hight AE, Glassman EK, Lavender A, Seward KP, Miller MK, Ding N, Tan CT, and Fitzgerald MB
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- Acoustic Stimulation methods, Acoustics, Humans, Noise, Cochlear Implantation methods, Cochlear Implants, Speech Perception
- Abstract
Hypothesis: This study tests the hypothesis that it is possible to find tone or noise vocoders that sound similar and result in similar speech perception scores to a cochlear implant (CI). This would validate the use of such vocoders as acoustic models of CIs. We further hypothesize that those valid acoustic models will require a personalized amount of frequency mismatch between input filters and output tones or noise bands., Background: Noise or tone vocoders have been used as acoustic models of CIs in hundreds of publications but have never been convincingly validated., Methods: Acoustic models were evaluated by single-sided deaf CI users who compared what they heard with the CI in one ear to what they heard with the acoustic model in the other ear. We evaluated frequency-matched models (both all-channel and 6-channel models, both tone and noise vocoders) as well as self-selected models that included an individualized level of frequency mismatch., Results: Self-selected acoustic models resulted in similar levels of speech perception and similar perceptual quality as the CI. These models also matched the CI in terms of perceived intelligibility, harshness, and pleasantness., Conclusion: Valid acoustic models of CIs exist, but they are different from the models most widely used in the literature. Individual amounts of frequency mismatch may be required to optimize the validity of the model. This may be related to the basalward frequency mismatch experienced by postlingually deaf patients after cochlear implantation., (Copyright © 2021, Otology & Neurotology, Inc.)
- Published
- 2021
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22. Reducing interaural tonotopic mismatch preserves binaural unmasking in cochlear implant simulations of single-sided deafness.
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Sagi E, Azadpour M, Neukam J, Capach NH, and Svirsky MA
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- Hearing, Humans, Cochlear Implantation, Cochlear Implants, Deafness diagnosis, Speech Perception
- Abstract
Binaural unmasking, a key feature of normal binaural hearing, can refer to the improved intelligibility of masked speech by adding masking that facilitates perceived separation of target and masker. A question relevant for cochlear implant users with single-sided deafness (SSD-CI) is whether binaural unmasking can still be achieved if the additional masking is spectrally degraded and shifted. CIs restore some aspects of binaural hearing to these listeners, although binaural unmasking remains limited. Notably, these listeners may experience a mismatch between the frequency information perceived through the CI and that perceived by their normal hearing ear. Employing acoustic simulations of SSD-CI with normal hearing listeners, the present study confirms a previous simulation study that binaural unmasking is severely limited when interaural frequency mismatch between the input frequency range and simulated place of stimulation exceeds 1-2 mm. The present study also shows that binaural unmasking is largely retained when the input frequency range is adjusted to match simulated place of stimulation, even at the expense of removing low-frequency information. This result bears implications for the mechanisms driving the type of binaural unmasking of the present study and for mapping the frequency range of the CI speech processor in SSD-CI users.
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- 2021
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23. Taming big data: Applying the experimental method to naturalistic data sets.
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Sagi E
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- Cognition, Humans, Big Data, Semantics
- Abstract
Psychological researchers have traditionally focused on lab-based experiments to test their theories and hypotheses. Although the lab provides excellent facilities for controlled testing, some questions are best explored by collecting information that is difficult to obtain in the lab. The vast amounts of data now available to researchers can be a valuable resource in this respect. By incorporating this new realm of data and translating it into traditional laboratory methods, we can expand the reach of the lab into the wilderness of human society. This study demonstrates how the troves of linguistic data generated by humans can be used to test theories about cognition and representation. It also suggests how similar interpretations can be made of other research in cognition. The first case tests a long-standing prediction of Gentner's natural partition hypothesis: that verb meaning is more subject to change due to the textual context in which it appears than is the meaning of nouns. Within a diachronic corpus, verbs and other relational words indeed showed more evidence of semantic change than did concrete nouns. In the second case, corpus statistics were employed to empirically support the existence of phonesthemes-nonmorphemic units of sound that are associated with aspects of meaning. A third study also supported this measure, by demonstrating that it corresponds with performance in a lab experiment. Neither of these questions can be adequately explored without the use of big data in the form of linguistic corpora.
- Published
- 2019
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24. Supersymmetry in the Insulating Phase of a Chain of Majorana Cooper Pair Boxes.
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Ebisu H, Sagi E, and Oreg Y
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The charging energy U of a small superconducting island containing Majorana zero modes-a Majorana Cooper-pair box-induces interactions between the Majorana zero modes. Considering a chain of many such boxes, a topological superconductor-insulator transition occurs when U is much larger than the transfer matrix element t between the boxes. In this Letter, we focus on the insulting phases occurring in this regime. We show that there are several competing insulating phases, and that the transition between them is described by a supersymmetric field theory with a central charge c=7/10. We obtain this result by mapping the model to a spin-1 system and through a field theoretical approach. The microscopic model we propose consists of a chain of Majorana Cooper-pair boxes with local tunneling between Majorana zero modes and local charging energy terms, which can be controlled by gate potentials, thus making its realization more feasible.
- Published
- 2019
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25. Deactivating cochlear implant electrodes to improve speech perception: A computational approach.
- Author
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Sagi E and Svirsky MA
- Subjects
- Acoustic Stimulation, Cues, Electric Stimulation, Hearing Loss physiopathology, Hearing Loss psychology, Humans, Persons With Hearing Impairments psychology, Cochlear Implantation instrumentation, Cochlear Implants, Computer Simulation, Hearing Loss rehabilitation, Models, Theoretical, Persons With Hearing Impairments rehabilitation, Signal Processing, Computer-Assisted, Speech Perception
- Abstract
A potential bottleneck to improving speech perception performance in cochlear implant (CI) users is that some of their electrodes may poorly encode speech information. Several studies have examined the effect of deactivating poorly encoding electrodes on speech perception with mixed results. Many of these studies focused on identifying poorly encoding electrodes by some measure (e.g. electrode discrimination, pitch ordering, threshold, CT-guided, masked modulation detection), but provide inconsistent criteria about which electrodes, and how many, should be deactivated, and without considering how speech information becomes distributed across the electrode array. The present simulation study addresses this issue using computational approaches. Previously validated models were used to generate predictions of speech scores as a function of all possible combinations of active electrodes in a 22-electrode array in three groups of hypothetical subjects representative of relatively better, moderate, and poorer performing CI users. Using high-performance computing, over 500 million predictions were generated. Although deactivation of the poorest encoding electrodes sometimes resulted in predicted benefit, this benefit was significantly less relative to predictions resulting from model-optimized deactivations. This trend persisted when using novel stimuli (i.e. other than those used for optimization) and when using different processing strategies. Optimum electrode deactivation patterns produced an average predicted increase in word scores of 10% with some scores increasing by more than 20%. Optimum electrode deactivation patterns typically included 11 to 19 (out of 22) active electrodes, depending on the performance group. Optimal active electrode combinations were those that maximized discrimination of speech cues, maintaining 80%-100% of the physical span of the array. The present study demonstrates the potential for further improving CI users' speech scores with appropriate selection of active electrodes., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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26. A Smartphone Application for Customized Frequency Table Selection in Cochlear Implants.
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Jethanamest D, Azadpour M, Zeman AM, Sagi E, and Svirsky MA
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- Adult, Aged, Auditory Perception, Female, Humans, Male, Middle Aged, Persons With Hearing Impairments, Pilot Projects, Speech Perception, Young Adult, Cochlear Implants, Smartphone, Software
- Abstract
Hypothesis: A novel smartphone-based software application can facilitate self-selection of frequency allocation tables (FAT) in postlingually deaf cochlear implant (CI) users., Background: CIs use FATs to represent the tonotopic organization of a normal cochlea. Current CI fitting methods typically use a standard FAT for all patients regardless of individual differences in cochlear size and electrode location. In postlingually deaf patients, different amounts of mismatch can result between the frequency-place function they experienced when they had normal hearing and the frequency-place function that results from the standard FAT. For some CI users, an alternative FAT may enhance sound quality or speech perception. Currently, no widely available tools exist to aid real-time selection of different FATs. This study aims to develop a new smartphone tool for this purpose and to evaluate speech perception and sound quality measures in a pilot study of CI subjects using this application., Methods: A smartphone application for a widely available mobile platform (iOS) was developed to serve as a preprocessor of auditory input to a clinical CI speech processor and enable interactive real-time selection of FATs. The application's output was validated by measuring electrodograms for various inputs. A pilot study was conducted in six CI subjects. Speech perception was evaluated using word recognition tests., Results: All subjects successfully used the portable application with their clinical speech processors to experience different FATs while listening to running speech. The users were all able to select one table that they judged provided the best sound quality. All subjects chose a FAT different from the standard FAT in their everyday clinical processor. Using the smartphone application, the mean consonant-nucleus-consonant score with the default FAT selection was 28.5% (SD 16.8) and 29.5% (SD 16.4) when using a self-selected FAT., Conclusion: A portable smartphone application enables CI users to self-select frequency allocation tables in real time. Even though the self-selected FATs that were deemed to have better sound quality were only tested acutely (i.e., without long-term experience with them), speech perception scores were not inferior to those obtained with the clinical FATs. This software application may be a valuable tool for improving future methods of CI fitting.
- Published
- 2017
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27. Contribution of formant frequency information to vowel perception in steady-state noise by cochlear implant users.
- Author
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Sagi E and Svirsky MA
- Subjects
- Acoustic Stimulation, Adult, Aged, Algorithms, Cues, Electric Stimulation, Female, Humans, Male, Middle Aged, Persons With Hearing Impairments psychology, Signal Processing, Computer-Assisted, Cochlear Implantation instrumentation, Cochlear Implants, Noise adverse effects, Perceptual Masking, Persons With Hearing Impairments rehabilitation, Speech Acoustics, Speech Intelligibility, Speech Perception
- Abstract
Cochlear implant (CI) recipients have difficulty understanding speech in noise even at moderate signal-to-noise ratios. Knowing the mechanisms they use to understand speech in noise may facilitate the search for better speech processing algorithms. In the present study, a computational model is used to assess whether CI users' vowel identification in noise can be explained by formant frequency cues (F1 and F2). Vowel identification was tested with 12 unilateral CI users in quiet and in noise. Formant cues were measured from vowels in each condition, specific to each subject's speech processor. Noise distorted the location of vowels in the F2 vs F1 plane in comparison to quiet. The best fit model to subjects' data in quiet produced model predictions in noise that were within 8% of actual scores on average. Predictions in noise were much better when assuming that subjects used a priori knowledge regarding how formant information is degraded in noise (experiment 1). However, the model's best fit to subjects' confusion matrices in noise was worse than in quiet, suggesting that CI users utilize formant cues to identify vowels in noise, but to a different extent than how they identify vowels in quiet (experiment 2).
- Published
- 2017
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28. Language Use and Coalition Formation in Multiparty Negotiations.
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Sagi E and Diermeier D
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- Humans, Psycholinguistics, Cooperative Behavior, Language, Negotiating
- Abstract
The alignment of bargaining positions is crucial to a successful negotiation. Prior research has shown that similarity in language use is indicative of the conceptual alignment of interlocutors. We use latent semantic analysis to explore how the similarity of language use between negotiating parties develops over the course of a three-party negotiation. Results show that parties that reach an agreement show a gradual increase in language similarity over the course of the negotiation. Furthermore, reaching the most financially efficient outcome is dependent on similarity in language use between the parties that have the most to gain from such an outcome., (Copyright © 2015 Cognitive Science Society, Inc.)
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- 2017
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29. Purity homophily in social networks.
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Dehghani M, Johnson K, Hoover J, Sagi E, Garten J, Parmar NJ, Vaisey S, Iliev R, and Graham J
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- Adult, Female, Humans, Male, Morals, Psychological Distance, Social Networking
- Abstract
Does sharing moral values encourage people to connect and form communities? The importance of moral homophily (love of same) has been recognized by social scientists, but the types of moral similarities that drive this phenomenon are still unknown. Using both large-scale, observational social-media analyses and behavioral lab experiments, the authors investigated which types of moral similarities influence tie formations. Analysis of a corpus of over 700,000 tweets revealed that the distance between 2 people in a social-network can be predicted based on differences in the moral purity content-but not other moral content-of their messages. The authors replicated this finding by experimentally manipulating perceived moral difference (Study 2) and similarity (Study 3) in the lab and demonstrating that purity differences play a significant role in social distancing. These results indicate that social network processes reflect moral selection, and both online and offline differences in moral purity concerns are particularly predictive of social distance. This research is an attempt to study morality indirectly using an observational big-data study complemented with 2 confirmatory behavioral experiments carried out using traditional social-psychology methodology., ((c) 2016 APA, all rights reserved).)
- Published
- 2016
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30. The neural encoding of formant frequencies contributing to vowel identification in normal-hearing listeners.
- Author
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Won JH, Tremblay K, Clinard CG, Wright RA, Sagi E, and Svirsky M
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- Adult, Aged, Cochlea physiology, Cues, Evoked Potentials, Auditory physiology, Female, Humans, Male, Middle Aged, Models, Neurological, Monte Carlo Method, Perceptual Masking physiology, Phonetics, Speech Acoustics, Young Adult, Recognition, Psychology physiology, Speech Perception physiology
- Abstract
Even though speech signals trigger coding in the cochlea to convey speech information to the central auditory structures, little is known about the neural mechanisms involved in such processes. The purpose of this study was to understand the encoding of formant cues and how it relates to vowel recognition in listeners. Neural representations of formants may differ across listeners; however, it was hypothesized that neural patterns could still predict vowel recognition. To test the hypothesis, the frequency-following response (FFR) and vowel recognition were obtained from 38 normal-hearing listeners using four different vowels, allowing direct comparisons between behavioral and neural data in the same individuals. FFR was employed because it provides an objective and physiological measure of neural activity that can reflect formant encoding. A mathematical model was used to describe vowel confusion patterns based on the neural responses to vowel formant cues. The major findings were (1) there were large variations in the accuracy of vowel formant encoding across listeners as indexed by the FFR, (2) these variations were systematically related to vowel recognition performance, and (3) the mathematical model of vowel identification was successful in predicting good vs poor vowel identification performers based exclusively on physiological data.
- Published
- 2016
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31. Bilateral cochlear implants with large asymmetries in electrode insertion depth: implications for the study of auditory plasticity.
- Author
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Svirsky MA, Fitzgerald MB, Sagi E, and Glassman EK
- Subjects
- Adult, Deafness physiopathology, Female, Humans, Auditory Perception physiology, Cochlear Implantation methods, Cochlear Implants, Deafness therapy
- Abstract
Conclusion: The human frequency-to-place map may be modified by experience, even in adult listeners. However, such plasticity has limitations. Knowledge of the extent and the limitations of human auditory plasticity can help optimize parameter settings in users of auditory prostheses., Objectives: To what extent can adults adapt to sharply different frequency-to-place maps across ears? This question was investigated in two bilateral cochlear implant users who had a full electrode insertion in one ear, a much shallower insertion in the other ear, and standard frequency-to-electrode maps in both ears., Methods: Three methods were used to assess adaptation to the frequency-to-electrode maps in each ear: (1) pitch matching of electrodes in opposite ears, (2) listener-driven selection of the most intelligible frequency-to-electrode map, and (3) speech perception tests. Based on these measurements, one subject was fitted with an alternative frequency-to-electrode map, which sought to compensate for her incomplete adaptation to the standard frequency-to-electrode map., Results: Both listeners showed remarkable ability to adapt, but such adaptation remained incomplete for the ear with the shallower electrode insertion, even after extended experience. The alternative frequency-to-electrode map that was tested resulted in substantial increases in speech perception for one subject in the short insertion ear.
- Published
- 2015
- Full Text
- View/download PDF
32. Identity, causality, and pronoun ambiguity.
- Author
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Sagi E and Rips LJ
- Subjects
- Comprehension, Humans, Judgment physiology, Social Identification, Language
- Abstract
This article looks at the way people determine the antecedent of a pronoun in sentence pairs, such as: Albert invited Ron to dinner. He spent hours cleaning the house. The experiment reported here is motivated by the idea that such judgments depend on reasoning about identity (e.g., the identity of the he who cleaned the house). Because the identity of an individual over time depends on the causal-historical path connecting the stages of the individual, the correct antecedent will also depend on causal connections. The experiment varied how likely it is that the event of the first sentence (e.g., the invitation) would cause the event of the second (the house cleaning) for each of the two individuals (the likelihood that if Albert invited Ron to dinner, this would cause Albert to clean the house, versus cause Ron to clean the house). Decisions about the antecedent followed causal likelihood. A mathematical model of causal identity accounted for most of the key aspects of the data from the individual sentence pairs., (Copyright © 2014 Cognitive Science Society, Inc.)
- Published
- 2014
- Full Text
- View/download PDF
33. Topological phase transition in a discrete quasicrystal.
- Author
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Sagi E and Eisenberg E
- Subjects
- Temperature, Models, Theoretical, Phase Transition
- Abstract
We investigate a two-dimensional tiling model. Even though the degrees of freedom in this model are discrete, it has a hidden continuous global symmetry in the infinite lattice limit, whose corresponding Goldstone modes are the quasicrystalline phasonic degrees of freedom. We show that due to this continuous symmetry and despite the apparent discrete nature of the model, a topological phase transition from a quasi-long-range ordered to a disordered phase occurs at a finite temperature, driven by vortex proliferation. We argue that some of the results are universal properties of two-dimensional systems whose ground state is a quasicrystalline state.
- Published
- 2014
- Full Text
- View/download PDF
34. Feasibility of real-time selection of frequency tables in an acoustic simulation of a cochlear implant.
- Author
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Fitzgerald MB, Sagi E, Morbiwala TA, Tan CT, and Svirsky MA
- Subjects
- Adult, Cochlear Implantation methods, Cochlear Implantation standards, Computer Simulation, Feasibility Studies, Female, Humans, Male, Middle Aged, Acoustic Stimulation methods, Audiology methods, Auditory Perception physiology, Cochlear Implants standards, Deafness rehabilitation, Speech Perception physiology
- Abstract
Objectives: Perception of spectrally degraded speech is particularly difficult when the signal is also distorted along the frequency axis. This might be particularly important for post-lingually deafened recipients of cochlear implants (CIs), who must adapt to a signal where there may be a mismatch between the frequencies of an input signal and the characteristic frequencies of the neurons stimulated by the CI. However, there is a lack of tools that can be used to identify whether an individual has adapted fully to a mismatch in the frequency-to-place relationship and if so, to find a frequency table that ameliorates any negative effects of an unadapted mismatch. The goal of the proposed investigation is to test the feasibility of whether real-time selection of frequency tables can be used to identify cases in which listeners have not fully adapted to a frequency mismatch. The assumption underlying this approach is that listeners who have not adapted to a frequency mismatch will select a frequency table that minimizes any such mismatches, even at the expense of reducing the information provided by this frequency table., Design: Thirty-four normal-hearing adults listened to a noise-vocoded acoustic simulation of a CI and adjusted the frequency table in real time until they obtained a frequency table that sounded "most intelligible" to them. The use of an acoustic simulation was essential to this study because it allowed the authors to explicitly control the degree of frequency mismatch present in the simulation. None of the listeners had any previous experience with vocoded speech, in order to test the hypothesis that the real-time selection procedure could be used to identify cases in which a listener has not adapted to a frequency mismatch. After obtaining a self-selected table, the authors measured consonant nucleus consonant word-recognition scores with that self-selected table and two other frequency tables: a "frequency-matched" table that matched the analysis filters with the noisebands of the noise-vocoder simulation, and a "right information" table that is similar to that used in most CI speech processors, but in this simulation results in a frequency shift equivalent to 6.5 mm of cochlear space., Results: Listeners tended to select a table that was very close to, but shifted slightly lower in frequency from the frequency-matched table. The real-time selection process took on average 2 to 3 min for each trial, and the between-trial variability was comparable with that previously observed with closely related procedures. The word-recognition scores with the self-selected table were clearly higher than with the right-information table and slightly higher than with the frequency-matched table., Conclusions: Real-time self-selection of frequency tables may be a viable tool for identifying listeners who have not adapted to a mismatch in the frequency-to-place relationship, and to find a frequency table that is more appropriate for them. Moreover, the small but significant improvements in word-recognition ability observed with the self-selected table suggest that these listeners based their selections on intelligibility rather than some other factor. The within-subject variability in the real-time selection procedure was comparable with that of a genetic algorithm, and the speed of the real-time procedure appeared to be faster than either a genetic algorithm or a simplex procedure.
- Published
- 2013
- Full Text
- View/download PDF
35. Identifying issue frames in text.
- Author
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Sagi E, Diermeier D, and Kaufmann S
- Subjects
- Abortion, Induced, Algorithms, Female, Humans, Pregnancy, Research Design, Public Opinion
- Abstract
Framing, the effect of context on cognitive processes, is a prominent topic of research in psychology and public opinion research. Research on framing has traditionally relied on controlled experiments and manually annotated document collections. In this paper we present a method that allows for quantifying the relative strengths of competing linguistic frames based on corpus analysis. This method requires little human intervention and can therefore be efficiently applied to large bodies of text. We demonstrate its effectiveness by tracking changes in the framing of terror over time and comparing the framing of abortion by Democrats and Republicans in the U.S.
- Published
- 2013
- Full Text
- View/download PDF
36. Subcutaneous fat necrosis.
- Author
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Tzvi-Behr S, Megged O, Schlesinger Y, Bin-Nun A, Sagi E, and Becker-Cohen R
- Subjects
- Female, Humans, Infant, Fat Necrosis diagnosis, Subcutaneous Fat pathology
- Published
- 2013
- Full Text
- View/download PDF
37. VALIDATION OF ACOUSTIC MODELS OF AUDITORY NEURAL PROSTHESES.
- Author
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Svirsky MA, Ding N, Sagi E, Tan CT, Fitzgerald M, Glassman EK, Seward K, and Neuman AC
- Abstract
Acoustic models have been used in numerous studies over the past thirty years to simulate the percepts elicited by auditory neural prostheses. In these acoustic models, incoming signals are processed the same way as in a cochlear implant speech processor. The percepts that would be caused by electrical stimulation in a real cochlear implant are simulated by modulating the amplitude of either noise bands or sinusoids. Despite their practical usefulness these acoustic models have never been convincingly validated. This study presents a tool to conduct such validation using subjects who have a cochlear implant in one ear and have near perfect hearing in the other ear, allowing for the first time a direct perceptual comparison of the output of acoustic models to the stimulation provided by a cochlear implant.
- Published
- 2013
- Full Text
- View/download PDF
38. What difference reveals about similarity.
- Author
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Sagi E, Gentner D, and Lovett A
- Subjects
- Humans, Models, Psychological, Psychomotor Performance, Reaction Time, Cognition, Discrimination, Psychological, Pattern Recognition, Visual
- Abstract
Detecting that two images are different is faster for highly dissimilar images than for highly similar images. Paradoxically, we showed that the reverse occurs when people are asked to describe how two images differ--that is, to state a difference between two images. Following structure-mapping theory, we propose that this disassociation arises from the multistage nature of the comparison process. Detecting that two images are different can be done in the initial (local-matching) stage, but only for pairs with low overlap; thus, "different" responses are faster for low-similarity than for high-similarity pairs. In contrast, identifying a specific difference generally requires a full structural alignment of the two images, and this alignment process is faster for high-similarity pairs. We described four experiments that demonstrate this dissociation and show that the results can be simulated using the Structure-Mapping Engine. These results pose a significant challenge for nonstructural accounts of similarity comparison and suggest that structural alignment processes play a significant role in visual comparison., (Copyright © 2012 Cognitive Science Society, Inc.)
- Published
- 2012
- Full Text
- View/download PDF
39. Current and planned cochlear implant research at New York University Laboratory for Translational Auditory Research.
- Author
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Svirsky MA, Fitzgerald MB, Neuman A, Sagi E, Tan CT, Ketten D, and Martin B
- Subjects
- Auditory Perception physiology, Biomedical Technology, Hearing Loss pathology, Hearing Loss physiopathology, Humans, New York City, Translational Research, Biomedical, Universities, Audiology, Cochlear Implantation, Cochlear Implants, Hearing Loss therapy
- Abstract
The Laboratory of Translational Auditory Research (LTAR/NYUSM) is part of the Department of Otolaryngology at the New York University School of Medicine and has close ties to the New York University Cochlear Implant Center. LTAR investigators have expertise in multiple related disciplines including speech and hearing science, audiology, engineering, and physiology. The lines of research in the laboratory deal mostly with speech perception by hearing impaired listeners, and particularly those who use cochlear implants (CIs) or hearing aids (HAs). Although the laboratory's research interests are diverse, there are common threads that permeate and tie all of its work. In particular, a strong interest in translational research underlies even the most basic studies carried out in the laboratory. Another important element is the development of engineering and computational tools, which range from mathematical models of speech perception to software and hardware that bypass clinical speech processors and stimulate cochlear implants directly, to novel ways of analyzing clinical outcomes data. If the appropriate tool to conduct an important experiment does not exist, we may work to develop it, either in house or in collaboration with academic or industrial partners. Another notable characteristic of the laboratory is its interdisciplinary nature where, for example, an audiologist and an engineer might work closely to develop an approach that would not have been feasible if each had worked singly on the project. Similarly, investigators with expertise in hearing aids and cochlear implants might join forces to study how human listeners integrate information provided by a CI and a HA. The following pages provide a flavor of the diversity and the commonalities of our research interests., (American Academy of Audiology.)
- Published
- 2012
- Full Text
- View/download PDF
40. [Tefillin-related contact dermatitis].
- Author
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Hashkes PJ and Sagi E
- Subjects
- Adolescent, Arm, Dermatitis, Allergic Contact diagnosis, Humans, Male, Patch Tests, Tanning, Dermatitis, Allergic Contact etiology, Jews, Potassium Dichromate immunology
- Abstract
We describe a 14 year-old male with a background of atopic dermatitis who developed a contact dermatitis reaction on the left arm to the leather straps of tefillin (phylacteries), a religious article worn by observant Jewish men from the age 13 years during most morning prayer services. Patch testing revealed contact allergy to potassium dichromate, a chemical involved in leather tanning. Placing the leather straps over clothing and later switching to potassium dichromate-free leather straps resolved the condition. It is important to recognize this uncommon phenomena in a population in which a large proportion regularly use this religious article.
- Published
- 2011
41. Hypnosis and acupuncture (hypnopuncture) for prurigo nodularis: a case report.
- Author
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Samuels N, Sagi E, Singer SR, and Oberbaum M
- Subjects
- Chronic Disease, Combined Modality Therapy, Female, Humans, Suggestion, Acupuncture Therapy methods, Hypnosis methods, Prurigo therapy
- Abstract
Prurigo Nodularis (PN) is a chronic pruritic skin condition for which current conventional therapies are of limited benefit and with potentially toxic effects. Acupuncture--the insertion of thin needles at specific points on the skin--has been shown to alleviate itching through a number of itch-associated mediator effects. Hypnosis has been shown to modify and reduce the intensity of itching as well. A 44 year-old woman presented with a 30-year history of a diffuse itchy rash diagnosed as PN. She had tried various antihistamine and corticosteroid medications, to no avail. A treatment regimen using hypnosis and acupuncture (hypnopuncture) was initiated, with significant reduction in the itching, size and number of skin lesions. Hypnopuncture may offer a synergistic and augmented response to treatment, though further research is needed to understand the true benefits of this combined regimen.
- Published
- 2011
42. A mathematical model of medial consonant identification by cochlear implant users.
- Author
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Svirsky MA, Sagi E, Meyer TA, Kaiser AR, and Teoh SW
- Subjects
- Adolescent, Adult, Aged, Cues, Deafness therapy, Humans, Middle Aged, Psychoacoustics, Young Adult, Cochlear Implants, Deafness physiopathology, Models, Neurological, Phonetics, Speech Perception physiology
- Abstract
The multidimensional phoneme identification model is applied to consonant confusion matrices obtained from 28 postlingually deafened cochlear implant users. This model predicts consonant matrices based on these subjects' ability to discriminate a set of postulated spectral, temporal, and amplitude speech cues as presented to them by their device. The model produced confusion matrices that matched many aspects of individual subjects' consonant matrices, including information transfer for the voicing, manner, and place features, despite individual differences in age at implantation, implant experience, device and stimulation strategy used, as well as overall consonant identification level. The model was able to match the general pattern of errors between consonants, but not the full complexity of all consonant errors made by each individual. The present study represents an important first step in developing a model that can be used to test specific hypotheses about the mechanisms cochlear implant users employ to understand speech.
- Published
- 2011
- Full Text
- View/download PDF
43. A model of incomplete adaptation to a severely shifted frequency-to-electrode mapping by cochlear implant users.
- Author
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Sagi E, Fu QJ, Galvin JJ 3rd, and Svirsky MA
- Subjects
- Acoustic Stimulation, Adult, Audiometry, Speech, Humans, Middle Aged, Noise, Predictive Value of Tests, Adaptation, Physiological physiology, Cochlear Implants, Models, Neurological, Phonetics, Speech Perception physiology
- Abstract
In the present study, a computational model of phoneme identification was applied to data from a previous study, wherein cochlear implant (CI) users' adaption to a severely shifted frequency allocation map was assessed regularly over 3 months of continual use. This map provided more input filters below 1 kHz, but at the expense of introducing a downwards frequency shift of up to one octave in relation to the CI subjects' clinical maps. At the end of the 3-month study period, it was unclear whether subjects' asymptotic speech recognition performance represented a complete or partial adaptation. To clarify the matter, the computational model was applied to the CI subjects' vowel identification data in order to estimate the degree of adaptation, and to predict performance levels with complete adaptation to the frequency shift. Two model parameters were used to quantify this adaptation; one representing the listener's ability to shift their internal representation of how vowels should sound, and the other representing the listener's uncertainty in consistently recalling these representations. Two of the three CI users could shift their internal representations towards the new stimulation pattern within 1 week, whereas one could not do so completely even after 3 months. Subjects' uncertainty for recalling these representations increased substantially with the frequency-shifted map. Although this uncertainty decreased after 3 months, it remained much larger than subjects' uncertainty with their clinically assigned maps. This result suggests that subjects could not completely remap their phoneme labels, stored in long-term memory, towards the frequency-shifted vowels. The model also predicted that even with complete adaptation, the frequency-shifted map would not have resulted in improved speech understanding. Hence, the model presented here can be used to assess adaptation, and the anticipated gains in speech perception expected from changing a given CI device parameter.
- Published
- 2010
- Full Text
- View/download PDF
44. A mathematical model of vowel identification by users of cochlear implants.
- Author
-
Sagi E, Meyer TA, Kaiser AR, Teoh SW, and Svirsky MA
- Subjects
- Acoustic Stimulation, Adult, Aged, Algorithms, Computer Simulation, Humans, Information Theory, Mathematical Concepts, Middle Aged, Psychoacoustics, Psycholinguistics, Speech, Young Adult, Cochlear Implants, Models, Neurological, Phonetics, Speech Perception
- Abstract
A simple mathematical model is presented that predicts vowel identification by cochlear implant users based on these listeners' resolving power for the mean locations of first, second, and/or third formant energies along the implanted electrode array. This psychophysically based model provides hypotheses about the mechanism cochlear implant users employ to encode and process the input auditory signal to extract information relevant for identifying steady-state vowels. Using one free parameter, the model predicts most of the patterns of vowel confusions made by users of different cochlear implant devices and stimulation strategies, and who show widely different levels of speech perception (from near chance to near perfect). Furthermore, the model can predict results from the literature, such as Skinner, et al. [(1995). Ann. Otol. Rhinol. Laryngol. 104, 307-311] frequency mapping study, and the general trend in the vowel results of Zeng and Galvin's [(1999). Ear Hear. 20, 60-74] studies of output electrical dynamic range reduction. The implementation of the model presented here is specific to vowel identification by cochlear implant users, but the framework of the model is more general. Computational models such as the one presented here can be useful for advancing knowledge about speech perception in hearing impaired populations, and for providing a guide for clinical research and clinical practice.
- Published
- 2010
- Full Text
- View/download PDF
45. The effect of temporal gap identification on speech perception by users of cochlear implants.
- Author
-
Sagi E, Kaiser AR, Meyer TA, and Svirsky MA
- Subjects
- Adult, Aged, Analysis of Variance, Humans, Middle Aged, Speech, Time, Young Adult, Cochlear Implants, Speech Perception, Time Perception
- Abstract
Purpose: This study examined the ability of listeners using cochlear implants (CIs) and listeners with normal hearing (NH) to identify silent gaps of different duration and the relation of this ability to speech understanding in CI users., Method: Sixteen NH adults and 11 postlingually deafened adults with CIs identified synthetic vowel-like stimuli that were either continuous or contained an intervening silent gap ranging from 15 ms to 90 ms. Cumulative d', an index of discriminability, was calculated for each participant. Consonant and consonant-nucleus-consonant (CNC) word identification tasks were administered to the CI group., Results: Overall, the ability to identify stimuli with gaps of different duration was better for the NH group than for the CI group. Seven CI users had cumulative d' scores that were no higher than those of any NH listener, and their CNC word scores ranged from 0% to 30%. The other 4 CI users had cumulative d' scores within the range of the NH group, and their CNC word scores ranged from 46% to 68%. For the CI group, cumulative d' scores were significantly correlated with their speech testing scores., Conclusions: The ability to identify silent gap duration may help explain individual differences in speech perception by CI users.
- Published
- 2009
- Full Text
- View/download PDF
46. Information transfer analysis: a first look at estimation bias.
- Author
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Sagi E and Svirsky MA
- Subjects
- Bias, Humans, Information Dissemination methods, Mathematics, Models, Biological, Probability, Speech Intelligibility, Communication, Hearing physiology, Phonation, Speech physiology
- Abstract
Information transfer analysis [G. A. Miller and P. E. Nicely, J. Acoust. Soc. Am. 27, 338-352 (1955)] is a tool used to measure the extent to which speech features are transmitted to a listener, e.g., duration or formant frequencies for vowels; voicing, place and manner of articulation for consonants. An information transfer of 100% occurs when no confusions arise between phonemes belonging to different feature categories, e.g., between voiced and voiceless consonants. Conversely, an information transfer of 0% occurs when performance is purely random. As asserted by Miller and Nicely, the maximum-likelihood estimate for information transfer is biased to overestimate its true value when the number of stimulus presentations is small. This small-sample bias is examined here for three cases: a model of random performance with pseudorandom data, a data set drawn from Miller and Nicely, and reported data from three studies of speech perception by hearing impaired listeners. The amount of overestimation can be substantial, depending on the number of samples, the size of the confusion matrix analyzed, as well as the manner in which data are partitioned therein.
- Published
- 2008
- Full Text
- View/download PDF
47. Identification variability as a measure of loudness: an application to gender differences.
- Author
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Sagi E, D'Alessandro LM, and Norwich KH
- Subjects
- Acoustic Stimulation methods, Auditory Threshold physiology, Female, Humans, Male, Regression Analysis, Discrimination, Psychological physiology, Loudness Perception physiology, Sex Characteristics, Weights and Measures
- Abstract
It is well known that discrimination response variability increases with stimulus intensity, closely related to Weber's Law. It is also an axiom that sensation magnitude increases with stimulus intensity. Following earlier researchers such as Thurstone, Garner, and Durlach and Braida, we explored a new method of exploiting these relationships to estimate the power function exponent relating sound pressure level to loudness, using the accuracy with which listeners could identify the intensity of pure tones. The log standard deviation of the normally distributed identification errors increases linearly with stimulus range in decibels, and the slope, a, of the regression is proportional to the loudness exponent, n. Interestingly, in a demonstration experiment, the loudness exponent estimated in this way is greater for females than for males.
- Published
- 2007
- Full Text
- View/download PDF
48. Quest for frustration driven distortion in Y2(Mo2)O(7).
- Author
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Sagi E, Ofer O, Keren A, and Gardner JS
- Abstract
We investigated the nature of the freezing in the geometrically frustrated Heisenberg spin glass Y2(Mo2)O(7) by measuring the temperature dependence of the static internal magnetic field distribution above the spin-glass temperature, Tg, using the muon spin relaxation technique. The evolution of the field distribution cannot be explained by changes in the spin susceptibility alone and suggests a lattice deformation. This possibility is addressed by numerical simulations of the Heisenberg Hamiltonian with magnetoelastic coupling at T > 0.
- Published
- 2005
- Full Text
- View/download PDF
49. Homozygous splice site mutations in PKP1 result in loss of epidermal plakophilin 1 expression and underlie ectodermal dysplasia/skin fragility syndrome in two consanguineous families.
- Author
-
Sprecher E, Molho-Pessach V, Ingber A, Sagi E, Indelman M, and Bergman R
- Subjects
- Child, Preschool, Female, Humans, Infant, Plakophilins, RNA Splicing, Syndrome, Consanguinity, Ectodermal Dysplasia genetics, Mutation, Proteins genetics
- Abstract
During the last years, a growing number of inherited skin disorders have been recognized to be caused by abnormal function of desmosomal proteins. In the present study, we describe the first female individuals affected with the ectodermal dysplasia/skin fragility syndrome (MIM604536), a rare autosomal recessive disease due to mutations in the PKP1 gene encoding plakophilin 1, a critical component of desmosomal plaque. One patient was shown to carry a homozygous splice site mutation in intron 4. The second patient displayed a homozygous recurrent mutation affecting the acceptor splice site of intron 1. Both mutations were associated with intraepidermal separation, widening of intercellular spaces, and abnormal desmosome ultrastructure, and were found to result in the absence of immunoreactive plakophilin 1 in the epidermis of the affected individuals. These two cases emphasize the role of molecular genetics in the assessment of congenital blistering in newborns and illustrate the importance of proper desmosomal activity for normal epidermis development and function.
- Published
- 2004
- Full Text
- View/download PDF
50. Deriving the loudness exponent from categorical judgments.
- Author
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Norwich KH and Sagi E
- Subjects
- Humans, Models, Theoretical, Judgment, Loudness Perception
- Abstract
The power function exponent for loudness is traditionally determined by means of a process of magnitude estimation. It is demonstrated in this paper that the exponent can also be obtained by using the procedure of absolute identification of sound intensity. It has been shown that subjects' responses to tones of a given intensity are distributed in a normal distribution whose variance depends on the range, R, over which the tones are distributed. By means of a standard statistical transformation, the normal density in log space is converted to the corresponding probability density in linear space. The power function exponent can then be obtained directly from the linear probability density. We also suggest that there is a direct relationship between the information calculated from experiments on absolute identification of sound intensity and the neurophysiological, poststimulus histogram measured in a nerve fiber in the auditory nerve.
- Published
- 2002
- Full Text
- View/download PDF
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