Relevant bibliographies by topics / Amplitude of accommodation

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  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Amplitude of accommodation'

Author: Grafiati
Published: 8 September 2021
Last updated: 26 January 2023

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Journal articles on the topic "Amplitude of accommodation"

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Glasser, Adrian, Machelle T. Pardue, Margot E. Andison, and Jacob G. Sivak. "A behavioral study of refraction, corneal curvature, and accommodation in raptor eyes." Canadian Journal of Zoology 75, no. 12 (December 1, 1997): 2010–20. http://dx.doi.org/10.1139/z97-834.

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Since there is much speculation in the literature regarding the accommodative abilities of raptors, we undertook a behavioral study of accommodation in the five families of raptors. The resting refractive state and amplitude of accommodation were measured using infrared video photorefraction in a variety of wild-caught and captive-bred raptors. The resting corneal curvature and the extent of changes in corneal curvature during accommodation (corneal accommodation) were measured using video keratometry. External ocular and head dimensions were measured with calipers to look for correlates with accommodative amplitude. In general, all eyes examined were of high optical quality and relatively free of aberrations. No significant refractive errors were recorded in any of the birds examined (< 1.0 diopters (D)). In general, significant amplitudes of accommodation were measured in the hawks (up to 25.0 D), but little accommodation was seen in the owls. Corneal accommodation ranging from 2.8 to 6.2 D in magnitude was recorded in a number of the hawks. These differences in the accommodative behaviors of the owls and hawks are discussed with respect to the limitations of the behavioral techniques used, differences in the degree of cooperation of the different species, and real differences in the accommodative abilities of the owls and hawks in relation to their accommodative needs, such as when feeding.
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Gyldenkerne, Anders, Nicolaj Aagaard, Malene Jakobsen, Carina Toftelund, and Jesper Hjortdal. "Changes in accommodative function following small-incision lenticule extraction for high myopia." PLOS ONE 15, no. 12 (December 30, 2020): e0244602. http://dx.doi.org/10.1371/journal.pone.0244602.

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Purpose To examine whether the amplitude of accommodation, the accommodative response, and the accommodative facility is affected and correlated with changes in higher-order aberrations for patients with high myopia surgically treated with small-incision lenticule extraction (SMILE). Methods 35 highly myopic eyes (myopic spherical equivalent of at least 6 diopters) of 35 patients treated with SMILE were included. Assessments were made before and 3 months after surgery. Donders push-up-method was used to measure the amplitude of accommodation. The accommodative response was assessed using an open-field autorefractor”Grand Seiko WAM-5500” (Grand Seiko Co. Ltd., Hiroshima, Japan) in combination with a Badal optometer and stimuli of accommodation at 0.0, 0.5, 1.25, 2.0, 3.0, and 4.0 D, respectively. Accommodative facility was measured at 40 cm with ±2,00D flipper lenses. All measurements of accommodation were performed monocularly with the refractive error corrected with soft contact lenses. Results The amplitude of accommodation did not change statistically significantly (mean difference -0.24 D (SD 0.98), 95% CI of mean difference -0.58 D to 0.11 D, paired-sample t(34) = -1.39; P = 0.17). The accommodative responses at 0.0, 0.5, 1.25, 2.0, 3.0, and 4.0 D did not statistically significantly change either (F(6,29) = 1.15; P = .36). Finally, the accommodative facility was also unchanged with a mean difference of 1.11 cycles per minute (SD 5.11, 95% CI of mean difference -0.64 to 2.87, paired-sample t(34) = 1.29; P = 0.21). No clinically significant associations between changes in accommodation and higher-order aberrations were found. Conclusions SMILE does not alter the amplitude of accommodation, the accommodative response, nor the accommodative facility for highly myopic patients, and the surgically induced corneal higher-order aberrations do not affect the accommodative function.
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Makhova, M. V., and V. V. Strakhov. "Interaction of accommodative and subjective diagnostic criteria of accommodation disorders." Russian Ophthalmological Journal 12, no. 3 (August 31, 2019): 13–19. http://dx.doi.org/10.21516/2072-0076-2019-12-3-13-19.

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Purpose: to study the relationship of accommodative (objective) and subjective criteria of different types of accommodation disorders.Material and methods. 62 patients (124 eyes) with myopic refraction, aged 10 to 18, were divided into 6 groups according to accommodation disorders types. All patients were tested objectively on a Speedy-i accommodograph, which determined the coefficient of accommodation response (CAR) and the coefficient of microfluctuations (CMF) and underwent MEM retinoscopy to determine the accommodation response. In addition, subjective methods were used to determine the amplitude of accommodation (by proximetry) and accommodation flexibility (by ±2 D flipper). Results. A rather close correlation was revealed between the accommodative and subjective evaluation criteria of ciliary muscle performance. Therefore, both the CAR and proximetry data may be used to determine accommodation amplitude. The power of accommodation response may be determined by CAR and MEM retinoscopy, while the accommodation state may be tested by CMF or accommodation flexibility.Conclusion. A statistically significant correlation between accommodative coefficients and the results of subjective tests enable the practitioners of outpatient care to use the available subjective methods of accommodation disorder diagnosis and, accordingly, determine the best suited optical correction and choose adequate methods of treatment of accommodation disorders.
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Ikaunieks, Gatis, Karola Panke, Madara Segliņa, Aiga Švede, and Gunta Krūmiņa. "Accommodative Amplitude in School-Age Children." Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. 71, no. 5 (October 26, 2017): 387–91. http://dx.doi.org/10.1515/prolas-2017-0065.

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Abstract In children, intensive near-work affects the accommodation system of the eye. Younger children, due to anatomical parameters, read at smaller distance than older children and we can expect that the accommodation system of younger can be affected more than that of older children. We wanted to test this hypothesis. Some authors showed that the norms of amplitude of accommodation (AA) developed by Hofstetter (1950) not always could be applied for children. We also wanted to verify these results. A total of 106 (age 7-15) children participated in the study. Distance visual acuity was measured for all children and only data of children with good visual acuity 1.0 or more (dec. units) were analysed (73 children). Accommodative amplitude was measured before and after lessons using subjective push-up technique (with RAF Near Point Ruler). The results showed that the amplitude of accommodation reduced significantly (p < 0.05) during the day and decrease of AA was similar in different age groups (about ~0.70 D). Additional measurements are needed to verify that the observed changes in AA were associated with fatigue effect. The results showed lower accommodation values compared to average values calculated according to the Hofstetter equation (p < 0.05).
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Ma, Martin Ming-Leung, Mitchell Scheiman, Cuiyun Su, and Xiang Chen. "Effect of Vision Therapy on Accommodation in Myopic Chinese Children." Journal of Ophthalmology 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/1202469.

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Introduction. We evaluated the effectiveness of office-based accommodative/vergence therapy (OBAVT) with home reinforcement to improve accommodative function in myopic children with poor accommodative response.Methods. This was a prospective unmasked pilot study. 14 Chinese myopic children aged 8 to 12 years with at least 1 D of lag of accommodation were enrolled. All subjects received 12 weeks of 60-minute office-based accommodative/vergence therapy (OBAVT) with home reinforcement. Primary outcome measure was the change in monocular lag of accommodation from baseline visit to 12-week visit measured by Shinnipon open-field autorefractor. Secondary outcome measures were the changes in accommodative amplitude and monocular accommodative facility.Results. All participants completed the study. The lag of accommodation at baseline visit was 1.29 ± 0.21 D and it was reduced to 0.84 ± 0.19 D at 12-week visit. This difference (−0.46 ± 0.22 D; 95% confidence interval: −0.33 to −0.58 D) is statistically significant (p<0.0001). OBAVT also increased the amplitude and facility by 3.66 ± 3.36 D (p=0.0013; 95% confidence interval: 1.72 to 5.60 D) and 10.9 ± 4.8 cpm (p<0.0001; 95% confidence interval: 8.1 to 13.6 cpm), respectively.Conclusion. Standardized 12 weeks of OBAVT with home reinforcement is able to significantly reduce monocular lag of accommodation and increase monocular accommodative amplitude and facility. A randomized clinical trial designed to investigate the effect of vision therapy on myopia progression is warranted.
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De-Hita-Cantalejo, Concepción, María-de-los-Ángeles Benítez-Rodríguez, María Carmen Sánchez-González, María-José Bautista-Llamas, and José-María Sánchez-González. "Accommodation Response Variations in University Students under High Demand for Near-Vision Activity." Life 12, no. 11 (November 9, 2022): 1837. http://dx.doi.org/10.3390/life12111837.

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The objective of this study was to investigate accommodation changes and visual discomfort in a university student population after a period of high demand for near-vision activity. A total of 50 university students aged between 20 and 22 years were recruited. The tests performed involved positive relative accommodation (PRA), negative relative accommodation (NRA), accommodation amplitude (AA), and monocular and binocular accommodative facility (MAF and BAF). Visual discomfort was measured on a scale involving a visual discomfort questionnaire (VDQ). All accommodative variables underwent changes during the exam period; specifically, regarding NRA and PRA, 30.4% and 15.1% of the studied population, respectively, appeared to be below average. Moreover, 42.3% of the population exhibited values below average in the second measure of AA. On the other hand, a small percentage of the population was below average in MAF and BAF measurements: 3% in the monocular right eye test, 6% in the left eye test, and 9.1% in the binocular facility test. Finally, the VDQ score did not reveal a statistically significant difference between the two measurements. Prolonged near-distance work, such as a university exams period, changed all accommodation systems (amplitude of accommodation, relative accommodation, and accommodation facility). These changes influence an accommodation excess that results in blurred vision, headache, and problems with focusing.
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Castagno, Victor Delpizzo, Manuel Augusto Pereira Vilela, Rodrigo Dalke Meucci, Deiner Paulo Martins Resende, Francis Huszar Schneid, Rafael Getelina, Maurício Rodrigues Nasiloski, and Anaclaudia Gastal Fassa. "Amplitude of Accommodation in Schoolchildren." Current Eye Research 42, no. 4 (October 18, 2016): 604–10. http://dx.doi.org/10.1080/02713683.2016.1220586.

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Kragha, I. K. O. K. "Measurement of amplitude of accommodation." Ophthalmic and Physiological Optics 9, no. 3 (July 1989): 342–43. http://dx.doi.org/10.1111/j.1475-1313.1989.tb00925.x.

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Yu, Hanyang, Wentao Li, Ziping Chen, Mengzhen Chen, Junwen Zeng, Xijiang Lin, and Feng Zhao. "Is Ocular Accommodation Influenced by Dynamic Ambient Illumination and Pupil Size?" International Journal of Environmental Research and Public Health 19, no. 17 (August 23, 2022): 10490. http://dx.doi.org/10.3390/ijerph191710490.

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Purpose: We investigated ocular accommodative responses and pupil diameters under different light intensities in order to explore whether changes in light intensity aid effective accommodation function training. Methods:A total of 29 emmetropic and myopic subjects (age range: 12–18 years) viewed a target in dynamic ambient light (luminance: 5, 100, 200, 500, 1000, 2000 and 3000 lux) and static ambient light (luminance: 1000 lux) at a 40 cm distance with refractive correction. Accommodation and pupil diameter were recorded using an open-field infrared autorefractor and an ultrasound biological microscope, respectively. Results: The changes in the amplitude of accommodative response and pupil diameter under dynamic lighting were 1.01 ± 0.53 D and 2.80 ± 0.75 mm, respectively, whereas in static lighting, those values were 0.43 ± 0.24 D and 0.77 ± 0.27 mm, respectively. The amplitude of accommodation and pupil diameter change in dynamic lighting (t = 6.097, p < 0.001) was significantly larger than that under static lighting (t = 16.115, p < 0.001).The effects of light level on both accommodation and pupil diameter were significant (p < 0.001). Conclusion: Accommodation was positively correlated with light intensity. The difference was about 1.0 D in the range of 0–3000 lux, which may lay the foundation for accommodative training through light intervention.
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López-Artero, Esther, Francisco Poyales, Nuria Garzón, Alicia Matamoros, Alba Sáez, Ying Zhou, and María García-Montero. "Changes in Accommodative and Binocular Function following Phakic Intraocular Lens for High and Low-to-Moderate Myopia." International Journal of Environmental Research and Public Health 19, no. 11 (May 31, 2022): 6716. http://dx.doi.org/10.3390/ijerph19116716.

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The aim was to evaluate accommodative and binocular function of phakic intraocular lens implantable collamer lens (ICL) in high and low-to-moderate myopia. Prospective comparative cohort study with 38 myopic patients who underwent ICL implantation were divided into two groups of 19 patients, each one based on the spherical equivalent (SE): high-power (SE ≤ −6 D) and low-to-moderate (SE > −6 D). The push-up amplitude of accommodation (AA), monocular accommodative facility (MAF), distance and near ocular deviation, near convergence amplitude, near point convergence (NPC), stereopsis, and accommodative convergence/accommodation (AC/A) ratio were assessed before surgery and 1 week and 1 month postoperatively. The mean residual refractive error at 1 month after surgery improved in both groups, 0.18 ± 0.34 D and 0.09 ± 0.26 D, respectively (p < 0.001). There was a significant decrease in AA in both groups between preoperatively and at 1-week (p = 0.001; p = 0.008, respectively) and 1-month follow-up (p = 0.001; p = 0.008). For the rest of the binocular measurements, no statistically significant postoperative changes were found in any group. This finding suggests follow-up studies on amplitude of accommodation in phakic intraocular lens ICL implantation.
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Dissertations / Theses on the topic "Amplitude of accommodation"

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Burns, D. H. "Investigation of a new clinical method of measuring amplitude of accommodation." Thesis, London South Bank University, 2017. http://researchopen.lsbu.ac.uk/2736/.

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Amplitude of Accommodation (AoA) is the extent of the eye's ability to accommodate, or focus over a range of distances. This thesis describes the mechanism of accommodation and reviews the literature concerning the measurement of accommodation's amplitude, its maximum range. The reasons for measuring the amplitude of accommodation, in routine clinical practice, are outlined. The aim of this study is to investigate the accuracy of a new clinical method of measuring amplitude of accommodation and to compare it to the prevalent method. Methods by which the amplitude of accommodation has been measured clinically are described and compared. Each method has inherent sources of error and these are examined individually to show how they affect the results of measurement. The new method of measurement, developed by the author, is introduced. Its basis, which may lead to a redefinition of amplitude of accommodation, is explained and contrasted with the rationale of existing methods. Experimental work is reported comparing accuracy of measurement using the new method (the TRU) with that of the prevalent method (Push- Up with the RAF Rule). Two techniques for using the TRU, distance-measurement and acuity-measurement, were examined and distance-measurement was shown to be more precise. The method-comparison was by repeated measures of results with both methods and with those of an objective reference method, the WAM-5500 autorefractor. The estimated 95% limits of agreement between the two test methods spanned 6.36 D (dioptres). The disparity of results appeared due more to differences between the test methods' trueness than their precision. The RAF Rule gave results that averaged 2.10 D higher than results with the TRU and 2.19 D higher than results with the WAM-5500 autorefractor. Measurements of AoA with the autorefractor were 67% more repeatable than measurements with the TRU and 114% more repeatable than measurements with the RAF Rule, although of questionable trueness. The estimated 95% limits of agreement of reproducibility between sessions spanned 6.57D for the established method but 2.89 D for the new method, and reproducibility between investigators similarly spanned 5.10 D for the established method and 2.56 D for the new method. The significance of these findings for clinical vision science is discussed and examined in the light of theoretical considerations of each method's validity. Suggestions are made for improving the accuracy of measurement of the amplitude of accommodation, which should improve the reliability of normative values in current clinical use.
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Yang, Chih Huang. "Vitamin D in dry eye and myopia." Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/113952/1/Chih%20Huang_Yang_Thesis.pdf.

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Vitamin D is important to human health with a variety of systemic diseases linked to vitamin D deficiency. The effect of a two month treatment of a vitamin D oral supplement on the ocular surface in older people with dry eye and on binocular vision in younger adults with short-sightedness was assessed. Vitamin D had a beneficial effect on symptoms of dry eye in older people and improved the accommodation function in younger adults. This work suggests that the development of vitamin D eye drops might be useful for these conditions.
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Brennand, David Alexander Arthur. "Individual differences in recognition times to random dot stereograms, complex diamond stereograms and amplitude judgements in ridge stereograms : the role of tonic accommodation stereograms." Thesis, University of Sheffield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.392544.

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Chaves, Daniela Pinto. "Influência da iluminação colorida nos parâmetros acomodativos em sujeitos com disfunções acomodativas." Master's thesis, 2019. http://hdl.handle.net/1822/66601.

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Dissertação de mestrado em Optometria Avançada
A influência da iluminação no sistema acomodativo é um tema ainda pouco explorado e cuja informação existente é relativamente antiga. Considerando a grande variedade de iluminação existente atualmente, é relevante perceber de que forma esta se relaciona com a acomodação em pacientes com disfunções acomodativas. Este estudo teve como objetivo avaliar a influência da cor da iluminação (verde e vermelho) nos parâmetros acomodativos, numa população com disfunções acomodativas, em comparação com os valores obtidos com iluminação branca. Dezassete sujeitos com idades compreendidas entre os 19 e 25 anos (20.94 ± 1.68 anos), participaram neste estudo, sendo a maioria do sexo feminino (71%). Aos sujeitos diagnosticados com alguma disfunção acomodativa foi medida a amplitude de acomodação (AA) e a flexibilidade acomodativa (FA) utilizando 3 tipos de iluminação (branco, verde e vermelho). Como fonte de luz foi utilizada uma lâmpada de LED’s sintonizáveis (Ledgima Luminary). Os resultados obtidos mostraram que os valores da AA medidos sob as diferentes condições de iluminação apresentaram diferenças estatisticamente significativas quando avaliados com a iluminação branca e vermelha (p<0.001) e com a iluminação verde e vermelha (p=0.018). Os valores da FA apresentaram diferenças estatisticamente significativas quando avaliados com as iluminações branca e verde (p=0.01) e branco e vermelho (p=0.012). Estes resultados permitem inferir que a AA em pacientes com disfunções acomodativas é influenciada pela cor da iluminação, com o iluminante vermelho a apresentar os valores mais baixos. Em contraponto, o iluminante branco apresentou valores superiores para a AA e para a FA, enquanto que os iluminantes verde e vermelho exibiram resultados semelhantes para a FA, mais baixos que com o iluminante branco.
The influence of lighting on the accommodative system is still a little explored theme and with existing information relatively old. Considering the wide variety of lighting currently available, it is relevant to explore how the color of the light relates with accommodation, in particular when accommodative dysfunctions are present. The aim of this study was to assess the influence on accommodative parameters of colored lighting (green and red) in a population with accommodative dysfunctions, comparing the results with the ones obtained with white lighting. Seventeen subjects aged between 19 and 25 years (20.94±1.68 years) participated in this study, the majority of them females (71%). Subjects diagnosed with some kind of accommodative dysfunction had the amplitude of accommodation (AA) and accommodative flexibility (AF) measured using 3 types of lighting (white, green and red). A tunable LED lamp was used as light source (Ledgima Luminary). The results obtained showed that the values of AA measured under the different lighting conditions presented statistically significant differences when assessed with white and red lighting (p<0.001) and with green and red lighting (p=0.018). The values of AF showed statistically significant differences when assessed with the white and green illuminations (p=0.01) and white and red (p=0.012). These results allows the inference that the AA is influenced by the color of the lighting, with the red illuminant having the lowest values. In contrast, the white illuminant showed higher values for AA and AF, while the green and red illuminants showed similar results for AF, lower than with white illuminant.
Este trabalho foi financiado por Fundos Nacionais através da FCT – Fundação para a Ciência e a Tecnologia no âmbito do projeto PTDC/FIS-OTI/31486/2017
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Mendes, Cristina João Correia da Cunha. "Variações de parâmetros acomodativos ao longo do dia." Master's thesis, 2012. http://hdl.handle.net/1822/22816.

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Dissertação de mestrado em Optometria Avançada
crescente uso de dispositivos eletrónicos de variados tamanhos em ambientes não ergonómicos e a exigência quer no estudo quer na atividade profissional, obriga à eficácia, rapidez e precisão no sistema visual. O estilo e a qualidade de vida influenciam o comportamento humano em que a visão é afetada provocando anomalias na visão binocular, alterações no erro refrativo e sintomatologia associada. Existem estudos longitudinais sobre estas variações. O objetivo deste trabalho foi verificar se existe alguma variação nos parâmetros acomodativos ao longo do dia perante atividades normais do dia-a-dia de cada pessoa. Pretendeu-se ainda verificar, no caso de existirem alterações, quais os fatores que poderiam influenciar essas alterações. Neste estudo, participaram 30 estudantes com a idade entre os 19 anos e os 27 anos a quem se realizaram exames de acuidade visual, amplitude de acomodação, atraso acomodativo e flexibilidade acomodativa em três horários diferentes durante o mesmo dia. Os resultados deste trabalho mostraram haver uma diminuição estatisticamente significativa na amplitude de acomodação entre o final da manhã e o final da tarde (0,43D) com maior diferença nos miopes. Na flexibilidade acomodativa verificou-se um aumento estatisticamente significativo entre o início da manhã e o final da tarde (1,3cpm).
The increasing use of electronic devices of varying sizes and non-ergonomic environment either in study or in professional activity requires the efficiency, speed and accuracy of the visual system. The style and quality of life influences human behavior in which vision is affected causing abnormalities in binocular vision, changes in refractive error and associated symptomatology. There are longitudinal studies about these variations. The aim of this study was to ascertain whether there is any variation in accommodative parameters through a normal day of each person and the most reported symptoms. We also aim to evaluate what factors could influence those changes. In this study, 30 students participated with age between 19 years and 27 years old to whom visual acuity tests, the amplitude of accommodation, accommodative lag and accommodative flexibility were carried out in three different times during the same day. The results of this study showed a statistically significant decrease in the amplitude of accommodation between the end of the morning and the afternoon (0.43D) with greater difference in miopes. Accommodative flexibility showed a statistically significant increase from the early morning and the late afternoon (1, 3cpm).
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Adler, P., Andy J. Scally, and Brendan T. Barrett. "Test-retest reproducibility of accommodation measurements gathered in an unselected sample of UK primary school children." 2012. http://hdl.handle.net/10454/6363.

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Purpose To determine the test-retest reproducibility of accommodation measurements gathered in an unselected sample of primary school children. Methods Monocular and binocular amplitudes of accommodation (AA) were collected by five different Testers using the push-up method in an unselected sample of school children (n=137, age: 8.1±2.1-years). Testing was conducted on three occasions (average testing interval: 8-days) in 91.2% of the children. Results The median AA was 19.1D, the variation due to the identity of the Tester was 3.1D (p<0.001) and the within-subject variation (which takes the variation due to Tester identity into account) was 5.2D. Around 75-79% of children exhibited monocular AAs-12D when tested on the first occasion, but more than 90% exhibited an AA-12D when subsequently tested. Around 74-80% of those with an AA<12D on the first occasion had values-12D on subsequent testing even though no treatment had been undertaken. Poorer initial AA measurements were less likely to improve on repeat testing. Conclusions Our results reveal substantial intra-individual variation in AA measurements, raising questions about the usefulness of this test in children aged 4-12-years. We suggest that AA assessment may prove most useful in children in this age range as a pass/fail check for substantially reduced AA, for example, where the AA is <12D. Our sample would suggest that the prevalence of persistently reduced AA may be around 3.2% when tested under binocular conditions and 4-6.4% when tested monocularly.
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Book chapters on the topic "Amplitude of accommodation"

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Chung, Ida. "Testing Accommodation in Children." In The Pediatric Eye Exam Quick Reference Guide, 200–221. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-7998-8044-8.ch010.

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Accommodation disorders are associated with a host of etiologies. Children with accommodative disorders can present with various symptoms including blur, fluctuating vision, eye pain, burning sensation, tired eyes, asthenopia, headaches, fatigue with near work, and excessive rubbing, blinking, or tearing. This chapter provides an overview of accommodation testing on pediatric patients in the clinical setting. The author describes the indications for accommodation testing and provides clinical pearls for testing accommodative function in children. The chapter covers the specific tests, equipment required, and step-by-step procedures for testing accommodative amplitude, accommodative response, and accommodative facility.
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Goss, David A. "Plotting Blur, Break, Recovery, and Amplitude Findings and Completing Graphs." In Ocular Accommodation, Convergence, and Fixation Disparity, 21–33. Elsevier, 1995. http://dx.doi.org/10.1016/b978-0-7506-9497-1.50009-1.

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Dória Silva, Humberto, Rostan Silvestre da Silva, Eduardo Dória Silva, Maria Tamires Dória Silva, Cristiana Pereira Dória, and Cristiane Pereira Dória. "Visual Impairment Caused by Monovision Surgical Design." In Current Cataract Surgical Techniques. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.95770.

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Neurophysiological anatomy of natural binocular vision shows the need to focus with both eyes to jointly produce the two corneas accommodation, correcting, in a compensatory way, the divergences inherent in the two different images, of the same visual field projected in the two distinct spaces, the two retinas. Corneal accommodation is part of the forced convection mechanism for the transfer of mobile mass in the cornea, trabecular meshwork and retina, to inhibit the accumulation of dehydrated intraocular metabolic residue, which can cause refractive errors in the cornea, obstruction of the trabecular meshwork and reduction of the amplitude of the signals produced by the phototransducers and sent to the brain. The IOL monovision surgical implantation technique differs from the physiology of natural binocular vision, which can cause after surgery disorders, described in this chapter, in that it imposes a different adaptation from the neurophysiological anatomy of human vision in addition to favoring the continuous progression of residue accumulation dehydrated intraocular metabolic and stimulate ocular.
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Eperjesi, Frank, Hannah Bartlett, and Mark Dunne. "Accommodative amplitude." In Ophthalmic Clinical Procedures, 55–56. Elsevier, 2007. http://dx.doi.org/10.1016/b978-0-08-044978-4.50020-4.

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Guyton, David. "Accommodative Amplitude Measurements After Surgery for Presbyopia." In Hyperopia and Presbyopia, 287–90. CRC Press, 2003. http://dx.doi.org/10.1201/b14217-27.

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Zaharia, Radu Serban M., and Rodica Manuela Gogonea. "The Impact of Seasonality on the Using of Accommodation Capacity in Operation in Romania." In Destination Management and Marketing, 111–21. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-2469-5.ch008.

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For accommodation service providers one of the main objectives is to obtain and maintain a higher degree of using of accommodation capacity in operation. Based on these considerations, the paper analyzes the evolution of the index of utilization of the accommodation capacity in operation in the development regions of Romania for a period of six years in order to reveal similarities and disparities between them. For this purpose, besides the analysis of the developments of the index of utilization of the accommodation capacity in operation, the evolution of dispersion spreading is also analyzed. Both the variability amplitudes of the two main indicators and their trend are analyzed. The conclusion of the study is the fact that in Romania, the dispersion of the index of the use of the accommodation capacity in operation had an increasing trend, which means that in terms of the ratio between demand and supply of accommodation, the disparities between development regions continue to grow with all the negative implications on the performance of the tourism industry in Romania.
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Ritter, Scott M., Joshua K. Meibos, and Ty S. Robinson. "Sequence Biostratigraphy of Carboniferous–Permian Boundary Strata in Western Utah: Deciphering Eustatic and Tectonic Controls on Sedimentation in the Antler–Sonoma Distal Foreland Basin." In Late Paleozoic and Early Mesozoic Tectonostratigraphy and Biostratigraphy of Western Pangea, 149–71. SEPM (Society for Sedimentary Geology), 2022. http://dx.doi.org/10.2110/sepmsp.113.07.

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The stratal architecture of the upper Ely Limestone and Mormon Gap Formation (Pennsylvanian–Lower Permian) in west-central Utah reflects the interaction of icehouse sea-level change and tectonic activity in the distal Antler–Sonoma foreland basin. Nineteen stratigraphic sections correlated by physical and biostratigraphic means provide a basis for tracing Carboniferous–Permian boundary strata over a north–south distance of 60 km. These formations can be subdivided into 14 unconformity-bounded, third-order depositional sequences of differing internal architecture and regional extent. Conodonts and fusulinids provide ages for selected sequences and parasequences, permitting correlation with tectonostratigraphic units in the proximal foreland in north-central Nevada and with selected Midcontinent cyclothems. The 14 third-order sequences stack into three second-order supersequences characterized by distinctive differences in facies and facies stacking patterns, regional continuity of cycles, relative abundance of dolomite and limestone, calculated rock accumulation rates, and the frequency and inferred duration of sequence-bounding hiatuses. These reflect the effect of high-frequency sea-level change on an intermittently subsiding distal foreland shelf. Sediment accommodation was relatively high during the Bashkirian through middle Moscovian (upper part of Lower Absaroka I supersequence) and again during the late Sakmarian and Artinskian (lower part of Lower Absaroka III supersequence) as a function of continuous subsidence and high-amplitude sea-level change. During the late Moscovian through upper Sakmarian (Lower Absaroka II supersequence), however, subsidence slowed or ceased in response to tectonic activity in north-central Nevada, with concomitant development of the West-Central Utah Highlands (forebulge). During this episode of reduced subsidence, intermittent sedimentation was driven by second- and third-order eustatic fluctuations in sea level. Constituent strata form a wedge of onlapping, northward-thinning sequences and parasequences deposited during selected third-order highstands of the Lower Absaroka II second-order sea-level event. Depositional sequences in the distal foreland are bounded by low-relief disconformities of variable duration, in contrast to the angular unconformities and intensely deformed tectonostratigraphic domains that characterize the proximal foreland basin in north-central Nevada.
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Conference papers on the topic "Amplitude of accommodation"

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Sarnowska-Habrat, Katarzyna, Boguslawa Dubik, and Marek Zajac. "Measurements of accommodation amplitude in polychromatic light." In 12th Czech-Slovak-Polish Optical Conference on Wave and Quantum Aspects of Contemporary Optics, edited by Jan Perina, Sr., Miroslav Hrabovsky, and Jaromir Krepelka. SPIE, 2001. http://dx.doi.org/10.1117/12.417856.

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Franco, Sandra M., Raquel Moreira, and João M. Linhares. "The influence of coloured lighting on ocular amplitude of accommodation." In IV International Conference on Applications of Optics and Photonics, edited by Manuel Filipe P. Martins Costa. SPIE, 2019. http://dx.doi.org/10.1117/12.2527402.

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Coloma, Pilar, Inmaculada Pascual, Dolores de Fez, and Vicente Camps. "Study of measurement and calculation of the relative amplitude of accommodation." In 8th Ibero American Optics Meeting/11th Latin American Meeting on Optics, Lasers, and Applications, edited by Manuel Filipe P. C. Martins Costa. SPIE, 2013. http://dx.doi.org/10.1117/12.2027493.

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Schumacher, S., U. Oberheide, H. Theuer, M. Fromm, T. Ripken, G. Gerten, W. Ertmer, and H. Lubatschowski. "fs-lentotomie: changing the accommodation amplitude of presbyopic human lenses by fs laser pulses." In European Conference on Biomedical Optics. Washington, D.C.: OSA, 2007. http://dx.doi.org/10.1364/ecbo.2007.6632_32.

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Schumacher, S., U. Oberheide, H. Theuer, M. Fromm, T. Ripken, G. Gerten, W. Ertmer, and H. Lubatschowski. "fs-lentotomie: changing the accommodation amplitude of presbyopic human lenses by fs laser pulses." In European Conference on Biomedical Optics, edited by Alfred Vogel. SPIE, 2007. http://dx.doi.org/10.1117/12.728197.

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Reilly, Matthew A. "Is Presbyopia Caused by Lens Growth-Induced Residual Stresses?" In ASME 2013 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/sbc2013-14528.

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Prevailing wisdom holds that increasing lens stiffness causes presbyopia. Treatments for presbyopia have therefore focused on altering the mechanical properties of the ocular lens. The present work shows an age-related decline in accommodation amplitude may be predicted without invoking changes in lens stiffness.
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Windt, Christian, Josh Davidson, Benazzou Akram, and John V. Ringwood. "Performance Assessment of the Overset Grid Method for Numerical Wave Tank Experiments in the OpenFOAM Environment." In ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-77564.

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To maximise the energy output of wave energy converters (WECs), large structural motions are desired. When simulating WEC performance in Computational Fluid Dynamics (CFD) based numerical wave tanks, these motions must be explicitly accommodated in the computational domain. Using well established mesh morphing (MM) methods, this explicit accommodation results in deformation of control volumes (CVs)/mesh. Thus, large amplitude WEC oscillations may lead to highly distorted CVs and push MM models beyond the limits of numerical stability. While advanced numerical mesh motion methods, such as overset grids, have been developed in commercial CFD codes to overcome these issues, little use of these methods can be found in WEC analysis. However, recently the overset grid method (OSG) has been made available to a wider user community through its release in the open source CFD environment OpenFOAM [1,2]. To evaluate the performance of the OSG, this paper will compare the classical MM method and the OSG against experimental tank test data of the WaveStar device [3].
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Wang, Sheng, Kangbin Lei, Xilian Luo, Kiwamu Kase, Elia Merzari, and Hisashi Ninokata. "Simulation of Eccentric-Shaft Journal Microbearing by DSMC." In ASME 2009 Fluids Engineering Division Summer Meeting. ASMEDC, 2009. http://dx.doi.org/10.1115/fedsm2009-78572.

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Many micromachines use rotating shafts and other moving parts which carry a load and need fluid bearings for support. Most of them operate with air or water as the lubricating fluid. The present study analyzes air microbearing represented as an eccentric cylinder rotating in a stationary housing. The fluid mechanics and operating characteristics of microbearing are different from their larger cousins. The small length-scale may invalidate the continuum approximation in Navier-Stokes equations, and slip flow, rarefaction, compressibility and other unconventional effects may have to be taken into account. Surface effects dominate in small devices due to a high surface-volume ratio. In this study, two-dimensional eccentric-shaft journal microbearings with different eccentricities are simulated by direct simulation Monte Carlo (DSMC) code incorporated with a Volume-CAD software. The diffuse reflection model and Cercignani-Lampis-Lord (CLL) model are applied to model the molecule-surface interaction by considering the accommodation coefficients of shaft wall and housing wall separately. The distribution of mean free path in the flow field indicates that the continuum model may break down and it is necessary to carry our molecular modeling. Calculation results show that at high eccentricity and high accommodation coefficient on the housing wall (ACO) the flow may develop a recirculation region. However, the accommodation coefficient on shaft wall (ACI) does not have any effect on the occurrence of recirculation and the size of recirculation zone. There is antisymmetry of the pressure about a vertical axis, which produces a pressure force on the shaft wall. The influence of ACI to isobars is larger than that of ACO. The shear stress profile on shaft wall is big at low ACI. At the region of short clearance between the shaft wall and housing wall, it is also influenced by the surface condition of housing wall and may even change its direction at low ACO. The pressure profile is reduced in amplitude as the ACI increases, but it is enhanced a little with the increase of ACO. The ACO has great impact on the viscous force in the case of big eccentricity. With the increase of ACI, the viscous force decreases. The pressure force is high at large eccentricity. The influence of ACO to pressure force is insignificant, but the pressure force fall is enormous when ACI increases, especially for large eccentricity. The total force decreases markedly at high eccentricity when ACI increases. The ACO almost has no impact on the total force. The torque increases with ACO, but decreases with ACI. The eccentricity also has great impact on the torque, and the microbeaing may have large torque at high eccentricity. The method developed in this paper would be very useful for designing and evaluating journal microbearing.
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Motriuk, Roman W., and Edwin Mikulcik. "Dynamic Support in Piping Systems: A Novel Design Based on Automotive Shock Absorbers." In ASME 2003 Pressure Vessels and Piping Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/pvp2003-2090.

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Complex vibration fields are observed in piping systems that are mechanically or acoustically interconnected with turbo-machinery. The magnitudes of vibrations in such systems depend on the coupling of the piping response characteristics with the excitations that are present. In cases of high vibration amplitudes, successful mechanical attenuation can be achieved by altering the piping system’s mass or its stiffness, thus detuning the piping response from the excitation. Another approach is to introduce damping into the piping system so that the vibration energy can be efficiently dissipated, hence mitigating unacceptable vibration amplitudes. All of the above principles are used successfully across the industry. This paper describes a novel support design that has been used successfully to solve vibration problems in cases such as those described above. This device was initially conceived as being a very economical solution for simply adding damping to reduce the vibration amplitude. Its economy is derived from being based on the use of standard automotive or truck-type shock absorbers, which were expected to be very effective in providing damping because of their success in automotive applications. The device which was designed is lightweight and therefore very versatile in the manner in which it can be deployed, such that anchoring and attachment requirements can be very simple, thus accommodating space or foundation necessities that could be problematic using more standard approaches. Because of the lack of information existing on the damping properties of such shock absorbers, the first design was implemented on a trial-and-error basis. However, its success motivated further investigations into the characteristics of shock absorbers, so that the initial installation could be evaluated through a more proper analysis and lead to a more general design procedure for other applications. Extensive laboratory tests were done using several different shock absorbers to gain an insight into their characteristics when used in the manner required here. The test procedures and the data from these tests are described in this paper, together with the analysis of the successful installation. It was found, unexpectedly, that the shock absorbers contribute significantly in both damping and stiffness, thus providing a powerful combination of detuning as well as damping when used in this way. This paper demonstrates a general approach to the techniques of testing and the design of similar such systems.
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Lessanibahri, Saman, Philippe Cardou, and Stéphane Caro. "A Cable-Driven Parallel Robot With an Embedded Tilt-Roll Wrist." In ASME 2019 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/detc2019-98146.

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Abstract This paper addresses the optimum design, configuration and workspace analysis of a Cable-Driven Parallel Robot with an embedded tilt-roll wrist. The manipulator is a hybrid robot consisting in an under-constrained moving-platform accommodating a tilt-roll wrist. The embedded wrist provides large amplitudes of tilt and roll rotations and a large translational workspace obtained by the moving-platform. This manipulator is suitable for tasks requiring large rotation and translation workspaces like tomography scanning, camera-orienting devices and visual surveillance. The moving-platform is an eight-degree-of-freedom articulated mechanism with large translational and rotational workspaces and it is suspended from a fixed frame by six cables. The manipulator employs two bi-actuated cables, i.e., cable loops to transmit the power from motors fixed on the ground to the tilt-roll wrist. Therefore, the manipulator achieves better dynamic performances due to a lower inertia of its moving-platform.
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