Sample records for accommodation epeiric carbonate

  1. Record of the Late Devonian Hangenberg global positive carbon-isotope excursion in an epeiric sea setting: Carbonate production, organic-carbon burial and paleoceanography during the late Famennian

    USGS Publications Warehouse

    Cramer, Bradley D.; Saltzman, Matthew R.; Day, J.E.; Witzke, B.J.

    2008-01-01

    Latest Famennian marine carbonates from the mid-continent of North America were examined to investigate the Late Devonian (very late Famennian) Hangenberg positive carbon-isotope (??13 Ccarb) excursion. This global shift in the ?? 13C of marine waters began during the late Famennian Hangenberg Extinction Event that occurred during the Middle Siphonodella praesulcata conodont zone. The post-extinction recovery interval spans the Upper S. praesulcata Zone immediately below the Devonian-Carboniferous boundary. Positive excursions in ?? 13 Ccarb are often attributed to the widespread deposition of organic-rich black shales in epeiric sea settings. The Hangenberg ??13 Ccarb excursion documented in the Louisiana Limestone in this study shows the opposite trend, with peak ??13 Ccarb values corresponding to carbonate production in the U.S. mid-continent during the highstand phase of the very late Famennian post-glacial sea level rise. Our data indicate that the interval of widespread black shale deposition (Hangenberg Black Shale) predates the peak isotope values of the Hangenberg ??13 Ccarb excursion and that peak values of the Hangenberg excursion in Missouri are not coincident with and cannot be accounted for by high Corg burial in epeiric seas. We suggest instead that sequestration and burial of Corg in the deep oceans drove the peak interval of the ??13Ccarb excursion, as a result of a change in the site of deep water formation to low-latitude epeiric seas as the global climate shifted between cold and warm states.

  2. Anatomy of an embayment in an Ordovician epeiric sea, Upper Mississippi Valley, USA

    NASA Astrophysics Data System (ADS)

    Simo, J. A. Toni; Emerson, Norlene R.; Byers, Charles W.; Ludvigson, Gregory A.

    2003-06-01

    The integration of stratigraphic, geochemical, and biostratigraphic data from Middle Ordovician carbonates and shales indicates that the North American epeiric sea was partitioned into shelf areas with distinct characteristics. The Upper Mississippi Valley part of the epeiric sea was appraised by using regionally traceable and geochemically “fingerprinted” K-bentonites, as well as detailed lithologic correlation. In the Midcontinent, the Decorah Formation records a time of high clastic sediment influx and abundant freshwater runoff from the Transcontinental Arch that created a salinity-stratified water column and led to episodic dysoxia. Later, relative flooding of the clastic source areas greatly reduced both the clastic sediment and freshwater runoff. As a result, the salinity stratification broke down, oxygenating the seafloor and permitting carbonates to form. Associated with this change, clarity of the water improved and the photic zone expanded, allowing seasonal blooms of Gloeocapsomorpha prisca to occur, resulting in increased burial of organic matter. The increase in G. prisca and total organic carbon coincided with, but lagged behind, a regional δ13C excursion. In addition, the timing of the initiation of the isotopic anomaly is different across the studied area, suggesting that local environmental conditions influenced the isotopic record. Data presented in this study support the partitioning of distinct areas within epeiric seas and the importance of this setting in storing inorganic and organic carbon and recording environmental and biological changes.

  3. The Miocene Nullarbor Limestone, southern Australia; deposition on a vast subtropical epeiric platform

    NASA Astrophysics Data System (ADS)

    O'Connell, Laura G.; James, Noel P.; Bone, Yvonne

    2012-05-01

    The early to middle Miocene Nullarbor Limestone forms the vast, karsted Nullarbor Plain in southern Australia, and may be the most extensive Miocene carbonate deposit described to date. These carbonates were deposited at southern paleolatitudes of ~ 40°S and are interpreted to be subtropical to warm-temperate in character because of the presence of certain genera of tropical coralline algae (rhodoliths and articulated types), large benthic foraminifera, tropical molluscs, zooxanthellate corals, and micrite envelopes. Facies are dominated by skeletal grainstones and floatstones that accumulated in three interpreted paleoenvironments: (1) seagrass banks (upper photic zone), (2) rhodolith pavements (lower photic zone), and (3) open seafloors (lower photic to subphotic zone). A decrease of tropical components from west to east across the platform implies that warm oceanic currents (possibly related to a proto-Leeuwin Current), as well as a period of warm climate (Miocene Climatic Optimum), resulted in subtropical deposition at southern latitudes. The Southern Ocean extended inboard ~ 450 km from the shelf edge during Nullarbor Limestone deposition, but interpreted paleodepths did not extend much below the base of the photic zone. A small slope angle (~ 0.02°) over a wide shelf (~ 300,000 km2) implies deposition on an epeiric platform or epeiric ramp. A Miocene barrier reef was likely coeval with Nullarbor Limestone deposition. Therefore, the inboard portion of the Nullarbor Limestone can be considered part of an extensive back-reef lagoon system on a rimmed epeiric platform, perhaps attaining a size similar to the modern Great Barrier Reef system.

  4. Contourites associated with pelagic mudrocks and distal delta-fed turbidites in the Lower Proterozoic Timeball Hill Formation epeiric basin (Transvaal Supergroup), South Africa

    NASA Astrophysics Data System (ADS)

    Eriksson, Patrick G.; Reczko, Boris F. F.

    1998-09-01

    Five genetic facies associations/architectural elements are recognised for the epeiric sea deposits preserved in the Early Proterozoic Timeball Hill Formation, South Africa. Basal carbonaceous mudrocks, interpreted as anoxic suspension deposits, grade up into sheet-like, laminated, graded mudrocks and succeeding sheets of laminated and cross-laminated siltstones and fine-grained sandstones. The latter two architectural elements are compatible with the Te, Td and Tc subdivisions of low-density turbidity current systems. Thin interbeds of stromatolitic carbonate within these first three facies associations support photic water depths up to about 100 m. Laterally extensive sheets of mature, cross-bedded sandstone disconformably overlie the turbidite deposits, and are ascribed to lower tidal flat processes. Interbedded lenticular, immature sandstones and mudrocks comprise the fifth architectural element, and are interpreted as medial to upper tidal flat sediments. Small lenses of coarse siltstone-very fine-grained sandstone, analogous to modern continental rise contourite deposits, occur within the suspension and distal turbidite sediments, and also form local wedges of inferred contourites at the transition from suspension to lowermost turbidite deposits. Blanketing and progressive shallowing of the floor of the Timeball Hill basin by basal suspension deposits greatly reduced wave action, thereby promoting preservation of low-density turbidity current deposits across the basin under stillstand or highstand conditions. A lowstand tidal flat facies tract laid down widespread sandy deposits of the medial Klapperkop Member within the formation. Salinity gradients and contemporaneous cold periglacial water masses were probably responsible for formation of the inferred contourites. The combination of the depositional systems interpreted for the Timeball Hill Formation may provide a provisional model for Early Proterozoic epeiric basin settings.

  5. Untold muddy tales: Paleoenvironmental dynamics of a ``barren'' mudrock succession from a shallow Permian epeiric sea

    NASA Astrophysics Data System (ADS)

    Simões, M. G.; Matos, S. A.; Warren, L. V.; Assine, M. L.; Riccomini, C.; Bondioli, J. G.

    2016-11-01

    During the late Paleozoic, the intracratonic Paraná Basin, Brazil, in central Gondwanaland, was covered by a huge (>1.600.000 km2), shallow and isolated epeiric sea. Within the Permian succession, oxygen-deficient facies are commonly recorded in the Mesosaurus-bearing Irati Formation (Cisuralian, Artinskian/Kungurian) and the overlaying Serra Alta Formation (Guadalupian, Wordian/Capitanian). Barren, dark-grey mudstones are the main facies preserved in this last unit, which has usually discouraged extensive and detailed stratigraphical and paleontological investigations. However, exhaustive sedimentological, taphonomic and paleontological surveys in those deposits reveal a dynamic and complex depositonal history. Based on sedimentary fabric, autochthonous to parautochthonous occurrences of shelly benthic invertebrates (bivalves) and the presence/absence of concretion-bearing and phosphate-rich layers, we report variations in the oxygen levels of bottom and pore waters, in bathymetry, sedimentation rates, and changes in benthic colonization. Our data indicate that the deposition of this "apparently barren" mudstone-dominated succession was driven by a complex interplay of variations in sedimentation rate and oxygen pulses tied to tectonic and climate changes. Three distinct populations or invertebrate paleocommunities were recorded, which were adapted to (a) normal background low-oxygen (dysoxic) conditions (i.e., minute infaunal suspension-feeding bivalves associated with the trace fossil Planolites), (b) chemically toxic (anoxic/extreme dysoxic) substrates, including gigantic burrowing bivalves (probable chemosymbiotic taxa), and (c) oxic/dysoxic substrates following short-term bottom disruptions.

  6. Noise coupling between accommodation and accommodative vergence

    NASA Technical Reports Server (NTRS)

    Wilson, D.

    1973-01-01

    For monocular viewing, the fluctuations in accommodative lens power in the frequency range from 0.5 to 3 Hz were found to be considerably greater than those in accommodative vergence movements of the covered eye. Considering the close synkinesis between these motor responses for step changes or slow variations in accommodative stimulus, this finding is unexpected. This apparent lack of synkinesis is found to result mainly from the fact that the decrease in small-signal linear gain with increasing frequency is more rapid in the case of the accommodative vergence system than in the case of the accommodation system, rather than from some nonlinear phenomenon.

  7. Differences in the Stimulus Accommodative Convergence/Accommodation Ratio using Various Techniques and Accommodative Stimuli.

    PubMed

    Satou, Tsukasa; Ito, Misae; Shinomiya, Yuma; Takahashi, Yoshiaki; Hara, Naoto; Niida, Takahiro

    2018-04-04

    To investigate differences in the stimulus accommodative convergence/accommodation (AC/A) ratio using various techniques and accommodative stimuli, and to describe a method for determining the stimulus AC/A ratio. A total of 81 subjects with a mean age of 21 years (range, 20-23 years) were enrolled. The relationship between ocular deviation and accommodation was assessed using two methods. Ocular deviation was measured by varying the accommodative requirement using spherical plus/minus lenses to create an accommodative stimulus of 10.00 diopters (D) (in 1.00 D steps). Ocular deviation was assessed using the alternate prism cover test in method 1 at distance (5 m) and near (1/3 m), and the major amblyoscope in method 2. The stimulus AC/A ratios obtained using methods 1 and 2 were calculated and defined as the stimulus AC/A ratios with low and high accommodation, respectively, using the following analysis method. The former was calculated as the difference between the convergence response to an accommodative stimulus of 3 D and 0 D, divided by 3. The latter was calculated as the difference between the convergence response to a maximum (max) accommodative stimulus with distinct vision of the subject and an accommodative stimulus of max minus 3.00 D, divided by 3. The median stimulus AC/A ratio with low accommodation (1.0 Δ/D for method 1 at distance, 2.0 Δ/D for method 1 at near, and 2.7 Δ/D for method 2) differed significantly among the measurement methods (P < 0.01). Differences in the median stimulus AC/A ratio with high accommodation (4.0 Δ/D for method 1 at distance, 3.7 Δ/D for method 1 at near, and 4.7 Δ/D for method 2) between method 1 at distance and method 2 were statistically significant (P < 0.05), while method 1 at near was not significantly different compared with other methods. Differences in the stimulus AC/A ratio value were significant according to measurement technique and accommodative stimuli. However, differences caused by

  8. [Objective accommodation parameters depending on accommodation task].

    PubMed

    Tarutta, E P; Tarasova, N A; Dolzhenko, O O

    2011-01-01

    62 myopic patients were examined to study objective accommodation parameters in different conditions of accommodation stimulus presenting (use of convex lenses). Objective accommodation response (OAR) was studied using binocular open-field autorefractometer in different conditions of stimulus presenting: complete myopia correction and adding of convex lenses with increasing power from +1.0 till +3.0 D. In 88,5% of children and adolescents showed significant decrease of OAR for 1,5-2,75D in 3.0D stimulus. Additional correction with convex lenses with increasing power leads to further reduce of accommodation response. As a result induced dynamic refraction in eye-lens system is lower than accommodation task. Only addition of +2,5D lense approximates it to required index of -3.0D.

  9. Short-term adaptation of accommodation, accommodative vergence and disparity vergence facility.

    PubMed

    Maxwell, James; Tong, Jianliang; Schor, Clifton M

    2012-06-01

    Previous studies have found that subjects can increase the velocity of accommodation using visual exercises such as pencil push ups, flippers, Brock strings and the like and myriad papers have shown improvement in accommodation facility (speed) and sufficiency (amplitude) using subjective tests following vision training but few have objectively measured accommodation before and after training in either normal subjects or in patients diagnosed with accommodative infacility (abnormally slow dynamics). Accommodation is driven either directly by blur or indirectly by way of neural crosslinks from the vergence system. Until now, no study has objectively measured both accommodation and accommodative-vergence before and after vision training and the role vergence might play in modifying the speed of accommodation. In the present study, accommodation and accommodative-vergence were measured with a Purkinje Eye Tracker/optometer before and after normal subjects trained in a flipper-like task in which the stimulus stepped between 0 and 2.5 diopters and back for over 200 cycles. Most subjects increased their speed of accommodation as well as their speed of accommodative vergence. Accommodative vergence led the accommodation response by approximately 77 ms before training and 100 ms after training and the vergence lead was most prominent in subjects with high accommodation and vergence velocities and the vergence leads tended to increase in conjunction with increases in accommodation velocity. We surmise that volitional vergence may help increase accommodation velocity by way of vergence-accommodation cross links. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Short-Term Adaptation of Accommodation, Accommodative Vergence and Disparity Vergence Facility

    PubMed Central

    Maxwell, James; Tong, Jianliang; Schor, Clifton M.

    2012-01-01

    Previous studies have found that subjects can increase the velocity of accommodation using visual exercises such as pencil push ups, flippers, Brock strings and the like and myriad papers have shown improvement in accommodation facility (speed) and sufficiency (amplitude) using subjective tests following vision training but few have objectively measured accommodation before and after training in either normal subjects or in patients diagnosed with accommodative infacility (abnormally slow dynamics). Accommodation is driven either directly by blur or indirectly by way of neural crosslinks from the vergence system. Until now, no study has objectively measured both accommodation and accommodative-vergence before and after vision training and the role vergence might play in modifying the speed of accommodation. In the present study, accommodation and accommodative-vergence were measured with a Purkinje Eye Tracker/Optometer before and after normal subjects trained in a flipper-like task in which the stimulus stepped between 0 and 2.5 diopters and back for over 200 cycles. Most subjects increased their speed of accommodation as well as their speed of accommodative vergence. Accommodative vergence led the accommodation response by approximately 77 msec before training and 100 msec after training and the vergence lead was most prominent in subjects with high accommodation and vergence velocities and the vergence leads tended to increase in conjunction with increases in accommodation velocity. We surmise that volitional vergence may help increase accommodation velocity by way of vergence-accommodation cross links. PMID:22480879

  11. Temporal accommodation response measured by photorefractive accommodation measurement device

    NASA Astrophysics Data System (ADS)

    Song, Byoungsub; Leportier, Thibault; Park, Min-Chul

    2017-02-01

    Although accommodation response plays an important role in the human vision system for perception of distance, some three-dimensional (3D) displays offer depth stimuli regardless of the accommodation response. The consequence is that most observers watching 3D displays have complained about visual fatigue. The measurement of the accommodation response is therefore necessary to develop human-friendly 3D displays. However, only few studies about accommodation measurement have been reported. Most of the investigations have been focused on the measurement and analysis of monocular accommodation responses only because the accommodation response works individually in each eye. Moreover, a main eye perceives dominantly the object distance. However, the binocular accommodation response should be examined because both eyes are used to watch the 3D display in natural conditions. The ophthalmic instrument that we developed enabled to measure changes in the accommodation response of the two eyes simultaneously. Two cameras acquired separately the infrared images reflected from each eyes after the reflected beams passed through a cylindrical lens. The changes in the accommodation response could then be estimated from the changes in the astigmatism ratio of the infrared images that were acquired in real time. In this paper, we compared the accommodation responses of main eye between the monocular and the binocular conditions. The two eyes were measured one by one, with only one eye opened, during measurement for monocular condition. Then the two eyes were examined simultaneously for binocular condition. The results showed similar tendencies for main eye accommodation response in both cases.

  12. STS payload data collection and accommodations analysis study. Volume 3: Accommodations analysis

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Payload requirements were compared to launch site accommodations and flight accommodations for a number of Spacelab payloads. Experiment computer operating system accommodations were also considered. A summary of accommodations in terms of resources available for payload discretionary use and recommendations for Spacelab/STS accommodation improvements are presented.

  13. Non-linearity of the response accommodative convergence to accommodation ratio.

    PubMed

    Johnston, Miriam S; Firth, Alison Y

    2013-09-01

    Previous studies have reported variation in stimulus accommodative convergence to accommodation (AC/A) ratio across differing accommodative stimuli. Response AC/A ratio was assessed across 4 accommodative demands to determine if these differences could be due to accommodative inaccuracies to stimuli. Twenty-three student participants aged 18 to 26 years (mean age 20.3 ± 1.7 years) successfully completed all testing conditions. The modified Thorington technique was used at 4 m to measure heterophoria. The Shin Nippon SRW 5000 infrared autorefractor was used to determine accommodative change to -1.50, -3.00, -4.50, and -6.00D lens stimuli. Significant differences were found in response AC/A ratio between different minus lens stimulated accommodative demands (p < 0.001). Mean AC/A ratio values were 3.11 ± 1.29 with the -1.50D lens stimulus; 4.03 ± 2.11 with -3.00D; 4.14 ± 1.40 with -4.50D; and 4.48 ± 1.56 with -6.00D. No differences in linearity were noted between myopes and non-myopic participants, but myopes tended to have higher response AC/A ratios than non-myopes, mean 4.88 ± 1.89 for myopes vs 3.61 ± 1.47 for non-myopes (p = 0.045). Response AC/A ratio did not display linearity across 4 minus lens accommodative stimuli, but tended to increase with accommodative demand. Significant variability in response AC/A ratio was found, both within individuals to different accommodative demands, and between individuals across the data set.

  14. Can current models of accommodation and vergence predict accommodative behavior in myopic children?

    PubMed

    Sreenivasan, Vidhyapriya; Irving, Elizabeth L; Bobier, William R

    2014-08-01

    Investigations into the progression of myopia in children have long considered the role of accommodation as a cause and solution. Myopic children show high levels of accommodative adaptation, coupled with accommodative lag and high response AC/A (accommodative convergence per diopter of accommodation). This pattern differs from that predicted by current models of interaction between accommodation and vergence, where weakened reflex responses and a high AC/A would be associated with a low not high levels of accommodative adaptation. However, studies of young myopes were limited to only part of the accommodative vergence synkinesis and the reciprocal components of vergence adaptation and convergence accommodation were not studied in tandem. Accordingly, we test the hypothesis that the accommodative behavior of myopic children is not predicted by current models and whether that departure is explained by differences in the accommodative plant of the myopic child. Responses to incongruent stimuli (-2D, +2D adds, 10 prism diopter base-out prism) were investigated in 28 myopic and 25 non-myopic children aged 7-15 years. Subjects were divided into phoria groups - exo, ortho and eso based upon their near phoria. The school aged myopes showed high levels of accommodative adaptation but with reduced accommodation and high AC/A. This pattern is not explained by current adult models and could reflect a sluggish gain of the accommodative plant (ciliary muscle and lens), changes in near triad innervation or both. Further, vergence adaptation showed a predictable reciprocal relationship with the high accommodative adaptation, suggesting that departures from adult models were limited to accommodation not vergence behavior. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. The influence of interactions between accommodation and convergence on the lag of accommodation.

    PubMed

    Schor, C

    1999-03-01

    Several models of myopia predict that growth of axial length is stimulated by blur. Accommodative lag has been suggested as an important source of blur in the development of myopia and this study has modeled how cross-link interactions between accommodation and convergence might interact with uncorrected distance heterophoria and refractive error to influence accommodative lag. Accommodative lag was simulated with two models of interactions between accommodation and convergence (one with and one without adaptable tonic elements). Simulations of both models indicate that both uncorrected hyperopia and esophoria increase the lag of accommodative and uncorrected myopia and exophoria decrease the lag or introduce a lead of accommodation in response to the near (40 cm) stimulus. These effects were increased when gain of either cross-link, accommodative convergence (AC/A) or convergence accommodation (CA/C), was increased within a moderate range of values while the other was fixed at a normal value (clamped condition). These effects were exaggerated when both the AC/A and CA/C ratios were increased (covaried condition) and affects of cross-link gain were negated when an increase of one cross-link (e.g. AC/A) was accompanied by a reduction of the other cross-link (e.g. CA/C) (reciprocal condition). The inclusion of tonic adaptation in the model reduced steady state errors of accommodation for all conditions except when the AC/A ratio was very high (2 MA/D). Combinations of cross-link interactions between accommodation and convergence that resemble either clamped or reciprocal patterns occur naturally in clinical populations. Simulations suggest that these two patterns of abnormal cross-link interactions could affect the progression of myopia differently. Adaptable tonic accommodation and tonic vergence could potentially reduce the progression of myopia by reducing the lag of accommodation.

  16. Vergence accommodation and monocular closed loop blur accommodation have similar dynamic characteristics.

    PubMed

    Suryakumar, Rajaraman; Meyers, Jason P; Irving, Elizabeth L; Bobier, William R

    2007-02-01

    Retinal blur and disparity are two different sensory signals known to cause a change in accommodative response. These inputs have differing neurological correlates that feed into a final common pathway. The purpose of this study was to investigate the dynamic properties of monocular blur driven accommodation and binocular disparity driven vergence-accommodation (VA) in human subjects. The results show that when response amplitudes are matched, blur accommodation and VA share similar dynamic properties.

  17. Random Changes of Accommodation Stimuli: An Automated Extension of the Flippers Accommodative Facility Test.

    PubMed

    Otero, Carles; Aldaba, Mikel; López, Silvia; Díaz-Doutón, Fernando; Vera-Díaz, Fuensanta A; Pujol, Jaume

    2018-06-01

    To study the accommodative dynamics for predictable and unpredictable stimuli using manual and automated accommodative facility tests Materials and Methods: Seventeen young healthy subjects were tested monocularly in two consecutive sessions, using five different conditions. Two conditions replicated the conventional monocular accommodative facility tests for far and near distances, performed with manually held flippers. The other three conditions were automated and conducted using an electro-optical system and open-field autorefractor. Two of the three automated conditions replicated the predictable manual accommodative facility tests. The last automated condition was a hybrid approach using a novel method whereby far and near-accommodative-facility tests were randomly integrated into a single test of four unpredictable accommodative demands. The within-subject standard deviations for far- and near-distance-accommodative reversals were (±1,±1) cycles per minute (cpm) for the manual flipper accommodative facility conditions and (±3, ±4) cpm for the automated conditions. The 95% limits of agreement between the manual and the automated conditions for far and near distances were poor: (-18, 12) and (-15, 3). During the hybrid unpredictable condition, the response time and accommodative response parameters were significantly (p < 0.05) larger for accommodation than disaccommodation responses for high accommodative demands only. The response times during the transitions 0.17/2.17 D and 0.50/4.50 D appeared to be indistinguishable between the hybrid unpredictable and the conventional predictable automated tests. The automated accommodative facility test does not agree with the manual flipper test results. Operator delays in flipping the lens may account for these differences. This novel test, using unpredictable stimuli, provides a more comprehensive examination of accommodative dynamics than conventional manual accommodative facility tests. Unexpectedly, the

  18. Disabling accommodation barriers: A study exploring how to better accommodate government employees with anxiety disorders.

    PubMed

    Mellifont, Damian; Smith-Merry, Jennifer; Scanlan, Justin Newton

    2016-11-22

    Accommodating mental health in the workplace is challenging. Despite policy efforts to encourage the availability of mental health accommodations in the workplace, employees experiencing mental illness are missing out on accommodations that they need. To inform vocational rehabilitation professionals and managers in the public service of best practice accommodations for government employees with anxiety disorders. Thematic analysis was applied to data collected from the online Accommodating Government Employees with Anxiety Disorders Survey undertaken by 71 Australian public service employees diagnosed with at least one anxiety disorder. Our research results include theme and sub-theme representations of accommodations received, accommodations reported as missing, accommodations that study participants felt they couldn't request, along with rejected accommodations. From the study participants' accounts, three key findings supporting desirable vocational outcomes become apparent. First, that the availability of 'standard' flexible work arrangements, along with personalised accommodations, can assist persons with anxiety disorders (where needed) to reach and retain government positions. Second, the chief barriers reported to making accommodation requests revolve around fears of being stigmatised and penalised. Finally, there is a need for managerial decision-makers to remain open-minded, particularly when assessing requests for accommodations that may break from government norms.

  19. [Effects of orthokeratology lenses on the magnitude of accommodative lag and accommodativeconvergence/accommodation].

    PubMed

    Ren, Qiujin; Yue, Hui; Zhou, Qing

    2016-02-01

    To evaluate the change in accommodative lag and accommodation convergence/accommodation (AC/A) after patients with myopia wear orthokeratology lenses. 
 A total of 48 myopic subjects (a test group), who wore orthokeratology lenses regularly, and 48 myopic subjects (a control group), who wore spectacles regularly, were enrolled for this study from January 2011 to January 2013 in Optometric Center, the Forth Hospital of Changsha. Accommodative lag was measured by fused cross cylinder method, where the patients should gaze at the front optotypes 40 cm away. Gradient of the AC/A ratio was measured by Von Grafe method to check closer distance heterophoria. Accommodative lag and AC/A ratio were analyzed by statistics.
 After 1-year follow-up, accommodative lag and AC/A rate in patients with low or moderate myopia in the test group was decreased in 1, 3, 6 months or 1 year compared with that in the control group (P<0.05). 
 Compared with spectacles, orthokeratology lenses are able to decrease accommodative lag and high AC/A rate in patients with low or moderate myopia. The relationship between accommodation and convergence is improved by orthokeratology lenses. Orthokeratology is an effective way to control myopia.

  20. Improving Accommodations Outcomes: Monitoring Instructional and Assessment Accommodations for Students with Disabilities

    ERIC Educational Resources Information Center

    Christensen, Laurene L.; Thurlow, Martha L.; Wang, Ting

    2009-01-01

    This document presents a five-step process for schools, districts, and states to use in monitoring accommodations for instruction and assessment. This document was designed to be a companion to the "Council of Chief State School Officers' Accommodations Manual: How to Select, Administer, and Evaluate Use of Accommodations for Instruction and…

  1. Visual accommodation trainer-tester

    NASA Technical Reports Server (NTRS)

    Randle, R. J., Jr. (Inventor)

    1983-01-01

    An apparatus for training of the human visual accommodation system is presented, specifically, useful for training a person to volitionally control his focus to his far point (normaly infinity) from a position of myopia due to functional causes. The functional causes could be due, for example, to a behavioral accommodative spasm or the effects of an empty field. The device may also be used to measure accommodation, the accommodation resting position and the near and far points of vision.

  2. The Accommodation Operation. Accommodation Management Module. Operational Management Programme.

    ERIC Educational Resources Information Center

    Chapman, Janet

    This module on accommodation operation is intended to help supervisors or managers achieve a balance in the day-to-day running of the premises and plan for a smooth and successful future. Much of the material is concerned with the housekeeping aspects of accommodation management. The material is presented in a self-instructional format in seven…

  3. [Energy and memory efficient calculation of the accommodation demand in the artificial accommodation system].

    PubMed

    Nagel, J A; Beck, C; Harms, H; Stiller, P; Guth, H; Stachs, O; Bretthauer, G

    2010-12-01

    Presbyopia and cataract are gaining more and more importance in the ageing society. Both age-related complaints are accompanied with a loss of the eye's ability to accommodate. A new approach to restore accommodation is the Artificial Accommodation System, an autonomous micro system, which will be implanted into the capsular bag instead of a rigid intraocular lens. The Artificial Accommodation System will, depending on the actual demand for accommodation, autonomously adapt the refractive power of its integrated optical element. One possibility to measure the demand for accommodation non-intrusively is to analyse eye movements. We present an efficient algorithm, based on the CORDIC technique, to calculate the demand for accommodation from magnetic field sensor data. It can be shown that specialised algorithms significantly shorten calculation time without violating precision requirements. Additionally, a communication strategy for the wireless exchange of sensor data between the implants of the left and right eye is introduced. The strategy allows for a one-sided calculation of the demand for accommodation, resulting in an overall reduction of calculation time by 50 %. The presented methods enable autonomous microsystems, such as the Artificial Accommodation System, to save significant amounts of energy, leading to extended autonomous run-times. © Georg Thieme Verlag KG Stuttgart · New York.

  4. Reasonable Accommodation Information Tracking System

    EPA Pesticide Factsheets

    The Reasonable Accommodation Information Tracking System (RAITS) is a case management system that allows the National Reasonable Accommodation Coordinator (NRAC) and the Local Reasonable Accommodation Coordinators (LORAC) to manage information related to Reasonable Accommodation (RA) requests. It provides a data base system in compliance with Executive Order 13164 and required by the Equal Employment Opportunity Commission (EEOC) Regulations and American Federation of Government Employees (AFGE) Bargaining Unit as described in the AFGE National Reasonable Accommodation Procedures. It is a tool that was internally developed in Lotus Notes to track requests for reasonable accommodation and was custom-configured to meet EPA's specific needs and infrastructure.

  5. Retinal Image Quality During Accommodation

    PubMed Central

    López-Gil, N.; Martin, J.; Liu, T.; Bradley, A.; Díaz-Muñoz, D.; Thibos, L.

    2013-01-01

    Purpose We asked if retinal image quality is maximum during accommodation, or sub-optimal due to accommodative error, when subjects perform an acuity task. Methods Subjects viewed a monochromatic (552nm), high-contrast letter target placed at various viewing distances. Wavefront aberrations of the accommodating eye were measured near the endpoint of an acuity staircase paradigm. Refractive state, defined as the optimum target vergence for maximising retinal image quality, was computed by through-focus wavefront analysis to find the power of the virtual correcting lens that maximizes visual Strehl ratio. Results Despite changes in ocular aberrations and pupil size during binocular viewing, retinal image quality and visual acuity typically remain high for all target vergences. When accommodative errors lead to sub-optimal retinal image quality, acuity and measured image quality both decline. However, the effect of accommodation errors of on visual acuity are mitigated by pupillary constriction associated with accommodation and binocular convergence and also to binocular summation of dissimilar retinal image blur. Under monocular viewing conditions some subjects displayed significant accommodative lag that reduced visual performance, an effect that was exacerbated by pharmacological dilation of the pupil. Conclusions Spurious measurement of accommodative error can be avoided when the image quality metric used to determine refractive state is compatible with the focusing criteria used by the visual system to control accommodation. Real focusing errors of the accommodating eye do not necessarily produce a reliably measurable loss of image quality or clinically significant loss of visual performance, probably because of increased depth-of-focus due to pupil constriction. When retinal image quality is close to maximum achievable (given the eye’s higher-order aberrations), acuity is also near maximum. A combination of accommodative lag, reduced image quality, and reduced

  6. Changes in dynamics of accommodation after accommodative facility training in myopes and emmetropes.

    PubMed

    Allen, Peter M; Charman, W Neil; Radhakrishnan, Hema

    2010-05-12

    This study evaluates the effect of accommodative facility training in myopes and emmetropes. Monocular accommodative facility was measured in nine myopes and nine emmetropes for distance and near. Subjective facility was recorded with automated flippers and objective measurements were simultaneously taken with a PowerRefractor. Accommodative facility training (a sequence of 5 min monocular right eye, 5 min monocular left eye, 5 min binocular) was given on three consecutive days and facility was re-assessed on the fifth day. The results showed that training improved the facility rate in both groups. The improvement in facility rates were linked to the time constants and peak velocity of accommodation. Some changes in amplitude seen in emmetropes indicate an improvement in facility rate at the expense of an accurate accommodation response. Copyright 2010 Elsevier Ltd. All rights reserved.

  7. Asymmetrical accommodation in hyperopic anisometropic amblyopia

    PubMed Central

    Toor, Sonia; Riddell, Patricia

    2018-01-01

    Background/aims To investigate the presence of asymmetrical accommodation in hyperopic anisometropic amblyopia. Methods Accommodation in each eye and binocular vergence were measured simultaneously using a PlusoptiX SO4 photorefractor in 26 children aged 4–8 years with hyperopic anisometropic amblyopia and 13 controls (group age-matched) while they viewed a detailed target moving in depth. Results Without spectacles, only 5 (19%) anisometropes demonstrated symmetrical accommodation (within the 95% CI of the mean gain of the sound eye of the anisometropic group), whereas 21 (81%) demonstrated asymmetrical accommodation. Of those, 15 (58%) showed aniso-accommodation and 6 (23%) demonstrated ‘anti-accommodation’ (greater accommodation for distance than for near). In those with anti-accommodation, the response gain in the sound eye was (0.93±0.20) while that of the amblyopic eye showed a negative accommodation gain of (−0.44±0.23). Anti-accommodation resolved with spectacles. Vergence gains were typical in those with symmetrical and asymmetrical accommodation. Conclusion The majority of hyperopic anisometropic amblyopes demonstrated non-consensual asymmetrical accommodation. Approximately one in four demonstrated anti-accommodation. PMID:29051327

  8. Job Accommodation Network

    MedlinePlus

    ADA LIBRARY PUBLICATIONS AND RESOURCES SEARCH ACCOMMODATIONS DATABASE A-Z OF DISABILITIES AND ACCOMMODATIONS NEWS Hot Topics How to Use this Site JAN en Español Print this Page A A A Text Size Connect with JAN (800)526-7234 (Voice) (877)781-9403 ( ...

  9. EBooks and Accommodations: Is This the Future of Print Accommodation?

    ERIC Educational Resources Information Center

    Cavanaugh, Terence

    2002-01-01

    This article explains the three components of eBooks: an eBook file, software to read the eBook, and a hardware device to read it on. The use of eBooks for students with special needs, the advantages of eBooks, built in accommodations, and creating accommodations are discussed. EBook resources are included. (Contains references.) (CR)

  10. Retinal image quality during accommodation.

    PubMed

    López-Gil, Norberto; Martin, Jesson; Liu, Tao; Bradley, Arthur; Díaz-Muñoz, David; Thibos, Larry N

    2013-07-01

    We asked if retinal image quality is maximum during accommodation, or sub-optimal due to accommodative error, when subjects perform an acuity task. Subjects viewed a monochromatic (552 nm), high-contrast letter target placed at various viewing distances. Wavefront aberrations of the accommodating eye were measured near the endpoint of an acuity staircase paradigm. Refractive state, defined as the optimum target vergence for maximising retinal image quality, was computed by through-focus wavefront analysis to find the power of the virtual correcting lens that maximizes visual Strehl ratio. Despite changes in ocular aberrations and pupil size during binocular viewing, retinal image quality and visual acuity typically remain high for all target vergences. When accommodative errors lead to sub-optimal retinal image quality, acuity and measured image quality both decline. However, the effect of accommodation errors of on visual acuity are mitigated by pupillary constriction associated with accommodation and binocular convergence and also to binocular summation of dissimilar retinal image blur. Under monocular viewing conditions some subjects displayed significant accommodative lag that reduced visual performance, an effect that was exacerbated by pharmacological dilation of the pupil. Spurious measurement of accommodative error can be avoided when the image quality metric used to determine refractive state is compatible with the focusing criteria used by the visual system to control accommodation. Real focusing errors of the accommodating eye do not necessarily produce a reliably measurable loss of image quality or clinically significant loss of visual performance, probably because of increased depth-of-focus due to pupil constriction. When retinal image quality is close to maximum achievable (given the eye's higher-order aberrations), acuity is also near maximum. A combination of accommodative lag, reduced image quality, and reduced visual function may be a useful

  11. Tonic accommodation predicts closed-loop accommodation responses.

    PubMed

    Liu, Chunming; Drew, Stefanie A; Borsting, Eric; Escobar, Amy; Stark, Lawrence; Chase, Christopher

    2016-12-01

    The purpose of this study is to examine the potential relationship between tonic accommodation (TA), near work induced TA-adaptation and the steady state closed-loop accommodation response (AR). Forty-two graduate students participated in the study. Various aspects of their accommodation system were objectively measured using an open-field infrared auto-refractor (Grand Seiko WAM-5500). Tonic accommodation was assessed in a completely dark environment. The association between TA and closed-loop AR was assessed using linear regression correlations and t-test comparisons. Initial mean baseline TA was 1.84diopter (D) (SD±1.29D) with a wide distribution range (-0.43D to 5.14D). For monocular visual tasks, baseline TA was significantly correlated with the closed-loop AR. The slope of the best fit line indicated that closed-loop AR varied by approximately 0.3D for every 1D change in TA. This ratio was consistent across a variety of viewing distances and different near work tasks, including both static targets and continuous reading. Binocular reading conditions weakened the correlation between baseline TA and AR, although results remained statistically significant. The 10min near reading task with a 3D demand did not reveal significant near work induced TA-adaptation for either monocular or binocular conditions. Consistently, the TA-adaptation did not show any correlation with AR during reading. This study found a strong association between open-loop TA and closed-loop AR across a variety of viewing distances and different near work tasks. Difference between the correlations under monocular and binocular reading condition suggests a potential role for vergence compensation during binocular closed-loop AR. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Habitability sleep accommodations

    NASA Technical Reports Server (NTRS)

    Fisher, H. T.

    1985-01-01

    Schematic outlines are presented with various design requirements for the accommodation of the spacecrew of Space Stations. The primary concern is for sleeping accommodations. Some other general requirements given are for a rest place, entertainment, dressing area, personal item stowage, body restraint, total privacy, external viewing, and grooming provisions. Several plans are given for sleep quarters concepts.

  13. Nonverbal Accommodation in Healthcare Communication

    PubMed Central

    D’Agostino, Thomas A.; Bylund, Carma L.

    2016-01-01

    This exploratory study examined patterns of nonverbal accommodation within healthcare interactions and investigated the impact of communication skills training and gender concordance on nonverbal accommodation behavior. The Nonverbal Accommodation Analysis System (NAAS) was used to code the nonverbal behavior of physicians and patients within 45 oncology consultations. Cases were then placed in one of seven categories based on patterns of accommodation observed across the interaction. Results indicated that across all NAAS behavior categories, physician-patient interactions were most frequently categorized as Joint Convergence, followed closely by Asymmetrical-Patient Convergence. Among paraverbal behaviors, talk time, interruption, and pausing were most frequently characterized by Joint Convergence. Among nonverbal behaviors, eye contact, laughing, and gesturing were most frequently categorized as Asymmetrical-Physician Convergence. Differences were predominantly non-significant in terms of accommodation behavior between pre and post-communication skills training interactions. Only gesturing proved significant, with post-communication skills training interactions more likely to be categorized as Joint Convergence or Asymmetrical-Physician Convergence. No differences in accommodation were noted between gender concordant and non-concordant interactions. The importance of accommodation behavior in healthcare communication is considered from a patient-centered care perspective. PMID:24138223

  14. Employer benefits from making workplace accommodations.

    PubMed

    Solovieva, Tatiana I; Dowler, Denetta L; Walls, Richard T

    2011-01-01

    This study explored workplace disability accommodations and their benefits. The participants were employers and human resource professionals who had not used the services of the Job Accommodation Network (JAN). The companies included large businesses (more than 499 employees) and small businesses (fewer than 500 employees). The intent of this investigation was to assess the disability accommodations and benefits for the employers. The study used responses to online survey from194 employers to discuss disability-related accommodations for an employee or potential employee. The survey included 128 employers who reported having had a person with a disability who requested an accommodation. As reported by the employers, the most frequently mentioned direct benefits from implementing workplace accommodations were (a) retained a qualified employee, (b) increased worker productivity, and (c) eliminated the cost of training a new employee. The most frequently mentioned indirect benefits from accommodations were (a) improved interactions with coworkers, (b) increased overall company morale, and (c) increased overall company productivity. The most frequently reported types of implemented accommodations were buying equipment and changing work schedules. Most of the respondents estimated the direct benefits of having made an accommodation at more than $1000. The findings heighten awareness of benefits associated with making accommodations for people with disabilities in the workplace. These benefits signify value for business, coworkers, and individuals with disabilities for whom accommodations are critical for successful employment. Published by Elsevier Inc.

  15. 43 CFR 17.211 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Reasonable accommodation. (a) A recipient shall make reasonable accommodation to the known physical or mental... that the accommodation would impose an undue hardship on the operation of its program or activity. (b... accommodation would impose an undue hardship on the operation of a recipient's program or activity, factors to...

  16. Vestibular-ocular accommodation reflex in man

    NASA Technical Reports Server (NTRS)

    Clark, B.; Randle, R. J.; Stewart, J. D.

    1975-01-01

    Stimulation of the vestibular system by angular acceleration produces widespread sensory and motor effects. The present paper studies a motor effect which has not been reported in the literature, i.e., the influence of rotary acceleration of the body on ocular accommodation. The accommodation of 10 young men was recorded before and after a high-level deceleration to zero velocity following 30 sec of rotating. Accommodation was recorded continuously on an infrared optometer for 110 sec under two conditions: while the subjects observed a target set at the far point, and while they viewed the same target through a 0.3-mm pinhole. Stimulation by high-level rotary deceleration produced positive accommodation or a pseudomyopia under both conditions, but the positive accommodation was substantially greater and lasted much longer during fixation through the pinhole. It is hypothesized that this increase in accommodation is a result of a vestibular-ocular accommodation reflex.

  17. Influence of accommodative lag upon the far-gradient measurement of accommodative convergence to accommodation ratio in strabismic patients.

    PubMed

    Miyata, Manabu; Hasebe, Satoshi; Ohtsuki, Hiroshi

    2006-01-01

    To determine the influence of the lag of accommodation (LOA) on the accommodative convergence to accommodation (AC/A) ratio measured by the far-gradient method in strabismic patients. The AC/A ratio was measured with a distance target viewed with and without -3.00 diopter (D) addition lenses in 63 patients with different types of strabismus (age range, 7-34 years; range of strabismic angle, -60 to +40 prism diopters; refractive error range, -7.33 to +6.63 D). The LOA for the same lens was measured with an open-view-type autorefractometer. The stimulus AC/A ratio and the AC/A ratio adjusted by the individually measured LOA (adjusted AC/A ratio) were compared. The mean +/- SD of the LOA to the -3.00 D lenses was 1.06 +/- 0.43 D. The mean adjusted AC/A ratio was 41% greater than the stimulus AC/A ratio. The LOA differed widely among patients (0.13 to 2.14 D), and a large LOA tended to appear in myopic or young patients. The AC/A ratio obtained using the conventional far-gradient method is significantly biased by the LOA, and thus does not always represent the actual relationship between accommodation and vergence control systems. Copyright Japanese Ophthalmological Society 2006.

  18. Medial rectus Faden operations with or without recession for partially accommodative esotropia associated with a high accommodative convergence to accommodation ratio.

    PubMed

    Akar, Serpil; Gokyigit, Birsen; Sayin, Nihat; Demirok, Ahmet; Yilmaz, Omer Faruk

    2013-01-01

    To evaluate the results of Faden operations on the medial rectus (MR) muscles with or without recession for the treatment of partially accommodative esotropia associated with a high accommodative convergence to accommodation (AC : A) ratio and to determine whether there was a decrease in the effects of posterior fixation over time. In this retrospective study, 108 of 473 patients who underwent surgery for partially accommodative esotropia with a high AC : A ratio received Faden operations on both MR muscles, and 365 received symmetric MR muscle recessions combined with a Faden operation. For the Faden operation, a satisfactory outcome of 76.9% at 1 month postoperation, decreased to 71.3% by the final follow-up visit (mean 4.8 years). A moderate positive correlation was observed between the increase in the postoperative near deviation and postoperative time. For the Faden operations combined with MR recession, a satisfactory outcome of 78.9% at 1 month post-operation, decreased to 78.4% by the final follow-up visit. A Faden operation of the MR muscles with or without recession is an effective surgical option for treating partially accommodative esotropia associated with a high AC : A ratio. For Faden operations of the MR muscles without recession, the effects of the posterior fixation decline over time.

  19. Vestibular-ocular accommodation reflex in man.

    PubMed

    Clark, B R; Randle, R J; Stewart, J D

    1975-11-01

    Stimulation of the vestibular system by angular acceleration produces widespread sensory and motor effects. The present study was designed to study a motor effect which has not been reported in the literature, i.e., the influence of rotary acceleration of the body on ocular accommodation. The accommodation of 10 young men was recorded before and after a high-level deceleration to zero velocity following 30 s of rotation. Accommodation was recorded continuously on an infrared optometer for 110 s under two conditions; while the subjects observed a target set at the far point, and while they viewed the same target through a 0.3-mm pinhole. Stimulation by high-level rotary deceleration produced positive accommodation or a pseudomyopia under both conditions, but the positive accommodation was substantially greater and lasted much longer during fixation through the pinhole. It is hypothesized that this increase in accommodation is a result of a vestibular-ocular accommodation reflex.

  20. A centre for accommodative vergence motor control

    NASA Technical Reports Server (NTRS)

    Wilson, D.

    1973-01-01

    Latencies in accommodation, accommodative-vergence, and pupil-diameter responses to changing accommodation stimuli, as well as latencies in pupil response to light-intensity changes were measured. From the information obtained, a block diagram has been derived that uses the least number of blocks for representing the accommodation, accommodative-vergence, and pupil systems. The signal transmission delays over the various circuits of the model have been determined and compared to known experimental physiological-delay data. The results suggest the existence of a motor center that controls the accommodative vergence and is completely independent of the accommodation system.

  1. Effects of Age on Dynamic Accommodation

    PubMed Central

    Lockhart, Thurmon E.; Shi, Wen

    2010-01-01

    Visual accommodation plays a critical role in one’s visual perception and activities of daily living. Age-related accommodation loss poses an increased risk to older adults’ safety and independence. Although extensive effort has been made towards understanding the effect of age on steady-state accommodation, dynamic aspects of accommodation is still unknown. A study was therefore conducted to investigate age-related dynamic accommodative characteristics utilizing a modified autorefractor. Ten individuals from each of three age groups (i.e., younger group: 20 to 29 years old, middle-aged group: 40 to 49 years old, and older group: 60 to 69 years old) were recruited and their dynamic accommodation responses were examined. The laboratory experiment was designed to assess dynamic accommodation associated with an abrupt change from a constant far target (400 cm, 50 cd/m2) to a near target (70 cm, 100 cd/m2 or 20 cd/m2), which aimed to simulate car dashboard reading behavior while driving. The results of the study indicated that age and target intensity both had a significant impact on dynamic accommodation. These effects were attributed to both the age-related physiological limitation of the eye as well as to central neural processing delay. A method of measuring dynamic accommodation and the implications of the study are discussed. PMID:20582770

  2. Experimental study of visual accommodation

    NASA Technical Reports Server (NTRS)

    Cornsweet, T. N.; Crane, H. D.

    1972-01-01

    A summary report of a research effort related to the human visual accommodation system is presented. A theoretical study of the accommodation system was made. Subsequent effort was aimed at the development of specialized instrumentation for experiments designed to lead to understanding the nature of the control system in human accommodation. The necessary instrumentation consisted primarily of: (1) an automatic optometer to measure the state of eye focus, (2) a focus stimulator device to control the apparent optical distance to any target, and (3) a two-dimensional eye tracker. The concepts and designs of the first two instruments have been published in the open literature, but this report contains the first detailed treatment of the Purkinje eye tracker developed under this program. The report also discusses an accommodation lag model to explain the ability of the eye to apparently know the polarity of focus error even though the blur on the retina is to a first-approximation an even function. The interaction of the accommodation and eye movement systems is also discussed, as is the ability to train the visual accommodation system to a surprisingly responsive condition in only a few hours of training.

  3. Handbook of Reasonable Accommodation.

    ERIC Educational Resources Information Center

    Heaton, Sandra M.; And Others

    The booklet discusses a basic concept in affirmative action and nondiscrimination for the handicapped, which requires federal agencies to make reasonable accommodation to the physical or mental limitations of a qualified handicapped applicant or employee unless the accommodation would impose an undue hardship on the agency. Reasonable…

  4. Accommodation-Amplitudes following an Accommodative Lens Refilling Procedure — an in vivo Update

    PubMed Central

    Nishi, Okihiro; Nishi, Yutaro; Chang, S.; Nishi, Kayo

    2014-01-01

    Purpose To investigate whether a newly developed lens refilling procedure can provide some accommodation in monkey eyes and to evaluate the difference in accommodation with different degrees of capsular bag refilling. Setting Jinshikai Medical Foundation, Nishi Eye Hospital, Osaka, Japan. Design Experimental monkey study. Methods Following a central 3–4 mm continuous curvilinear capsulorhexis, phacoemulsification was performed in the usual manner. A novel accommodative membrane intraocular lens for sealing capsular opening was implanted into the capsular bag. Silicone polymers were injected beneath the intraocular lens into the capsular bag through the delivery hole. In three study groups, each with six monkey eyes, the lens capsule was refilled with 0.08 ml corresponding to 65% bag volume, 0.1 ml corresponding to 80% bag volume, and 0.125 ml of silicone polymers corresponding to 100% bag volume, respectively. To calculate the accommodation-amplitudes achieved, automated refractometry was performed before and 1 hour after the topical 4% pilocarpine application before and four weeks after surgery. Results The refilling technique was successful in all monkeys without polymer leakage. Accommodation-amplitudes attained were 2.56 ± 0.74 dioptries (D), 2.42 ± 1.00D, and 2.71 ± 0.63D, respectively, 4 weeks after surgery in the three study groups. Conclusions Using the technique, some accommodation could be obtained in the young monkey eyes. Leakage of the injectable silicone polymer and anterior capsular opacification at least in the visual axis could be avoided. The results suggest that this lens refilling procedure warrants further studies for a possible clinical application. PMID:24461501

  5. 24 CFR 8.11 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... make reasonable accommodation to the known physical or mental limitations of an otherwise qualified... accommodation would impose an undue hardship on the operation of its program. (b) Reasonable accommodation may... hardship on the operation of a recipient's program, factors to be considered include: (1) The overall size...

  6. Independent and reciprocal accommodation in anisometropic amblyopia

    PubMed Central

    Horwood, Anna M.; Riddell, Patricia M

    2015-01-01

    Accommodation is considered to be a symmetrical response, and to be driven by the least ametropic and nonamblyopic eye in anisometropia. We report a case of a 4-year-old child with anisometropic amblyopia who accommodates asymmetrically, reliably demonstrating normal accommodation in the nonamblyopic eye and anti-accommodation of the amblyopic eye to near targets. The abnormal accommodation of the amblyopic eye remained largely unchanged over seven subsequent testing sessions undertaken over the course of therapy. We suggest that a congenital dysinnervation syndrome may result in relaxation of accommodation in relation to near cues and might be a hitherto-unconsidered additional etiologic factor in anisometropic amblyopia. PMID:20863728

  7. Chronostratigraphy and hydrocarbon habitat associated with the Jurassic carbonates of Abu Dhabi, United Arab Emirates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alsharahan, A.S.; Whittle, G.L.

    1995-08-01

    Deposition of Jurassic epeiric shelf carbonates and evaporates were controlled by epeirogenic movement and sea level fluctuations which formed an excellent combination of source rocks, reservoirs and seats in Abu Dhabi. At the end of the Triassic, a relative drop in sea level, caused by eustatic sea level lowering in conjunction with minor tectonic uplift, resulted in non-deposition or erosion. In the Toarcian, deposition of carbonates and terrigenous, clastics produced the Marrat Formation. In the mid-Aalenian, a drop in sea level eroded much of the Marrat and some of the Triassic in offshore U.A.E. The deposition of the Hamlah Formationmore » followed, under neritic, well-oxygenated conditions. The Middle Jurassic was characterized by widespread, normal marine shelf carbonates which formed the cyclic Izhara and Araej formations (reservoirs). In the Upper Jurassic, the carbonate shelf became differentiated into a broad shelf with a kerogen-rich intrashelf basin, formed in response to a eustatic rise coupled with epeirogenic downwarping and marine flooding. The intrashelf basin fill of muddy carbonate sediments constitutes the Diyab Formation and its onshore equivalent, the Dukhan Formation (source rocks). In the late Upper Jurassic, the climate became more arid and cyclic deposition of carbonates and evaporates prevailed, forming alternating peritidal anhydrite, dolomite and limestone in the Arab Formation (reservoir). Arid conditions continued into the Tithonian, fostering the extensive anhydrite of the Hith Formation (seal) in a sabkha/lagoonal setting on the shallow peritidal platform, the final regressive supratidal stage of this major depositional cycle.« less

  8. 22 CFR 217.12 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... accommodation. (a) A recipient shall make reasonable accommodation to the known physical or mental limitations... the accommodation would impose an undue hardship on the operation of its program or activity. (b... would impose an undue hardship on the operation of a recipient's program or activity, factors to be...

  9. Effect of heterophoria measurement technique on the clinical accommodative convergence to accommodation ratio.

    PubMed

    Escalante, Jaime Bernal; Rosenfield, Mark

    2006-05-01

    Measurement of the stimulus accommodative convergence to accommodation (AC/A) ratio is a standard procedure in clinical optometric practice. Typically, heterophoria is assessed at several accommodative stimulus levels, and the gradient of the vergence to accommodation function computed. A number of procedures are available for the subjective measurement of heterophoria, but it is unclear whether the use of different vergence measurement techniques will alter the obtained AC/A value. Accordingly, the current study compared AC/A ratios measured using 3 clinical subjective heterophoria tests, namely the von Graefe (VG), Maddox Rod (MR), and Modified Thorington (MT) procedures. The AC/A ratio was measured in 60 visually normal subjects between 20 and 25 years of age using each of the 3 procedures listed above. The accommodative stimulus was varied by the introduction of +/-1.00 diopter (D) spherical lenses over the distance refractive correction while subjects viewed a target at a viewing distance of 40 cm. To examine the repeatability of each procedure, the AC/A ratio was measured on 2 separate occasions for each measurement technique, with the 2 sessions being separated by at least 24 hours. Mean values of stimulus AC/A ratio measured using the VG, MR, and MT procedures were 3.47, 2.99, and 2.46Delta/D, respectively. These differences were significant (p=0.0001). In addition, the coefficient of repeatability for the 3 techniques was 2.22, 1.99, and 1.20 Delta/D, respectively. Ratios obtained using the Modified Thorington technique with +/-1.00 D lenses showed the best repeatability, whereas the poorest repeatability was found with the von Graefe technique when only +1.00 D lenses were used to vary the accommodative stimulus. Accordingly, we recommend that that Modified Thorington procedure with +/-1.00 D lenses be used to quantify heterophoria during clinical measurement of the stimulus AC/A ratio.

  10. 46 CFR 108.143 - Accommodation space.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Accommodation space. 108.143 Section 108.143 Shipping... EQUIPMENT Construction and Arrangement Structural Fire Protection § 108.143 Accommodation space. (a) Each corridor bulkhead in an accommodation space must be an A class or B class bulkhead except if an A class...

  11. 46 CFR 108.143 - Accommodation space.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Accommodation space. 108.143 Section 108.143 Shipping... EQUIPMENT Construction and Arrangement Structural Fire Protection § 108.143 Accommodation space. (a) Each corridor bulkhead in an accommodation space must be an A class or B class bulkhead except if an A class...

  12. 46 CFR 108.143 - Accommodation space.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Accommodation space. 108.143 Section 108.143 Shipping... EQUIPMENT Construction and Arrangement Structural Fire Protection § 108.143 Accommodation space. (a) Each corridor bulkhead in an accommodation space must be an A class or B class bulkhead except if an A class...

  13. 46 CFR 108.143 - Accommodation space.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Accommodation space. 108.143 Section 108.143 Shipping... EQUIPMENT Construction and Arrangement Structural Fire Protection § 108.143 Accommodation space. (a) Each corridor bulkhead in an accommodation space must be an A class or B class bulkhead except if an A class...

  14. 46 CFR 108.143 - Accommodation space.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Accommodation space. 108.143 Section 108.143 Shipping... EQUIPMENT Construction and Arrangement Structural Fire Protection § 108.143 Accommodation space. (a) Each corridor bulkhead in an accommodation space must be an A class or B class bulkhead except if an A class...

  15. The effect of bifocal add on accommodative lag in myopic children with high accommodative lag.

    PubMed

    Berntsen, David A; Mutti, Donald O; Zadnik, Karla

    2010-12-01

    To determine the effect of a bifocal add and manifest correction on accommodative lag in myopic children with high accommodative lag, who have been reported to have the greatest reduction in myopia progression with progressive addition lenses (PALs). Monocular accommodative lag to a 4-D Badal stimulus was measured on two occasions 6 months apart in 83 children (mean ± SD age, 9.9 ± 1.3 years) with high lag randomized to wearing single-vision lenses (SVLs) or PALs. Accommodative lag was measured with the following corrections: habitual, manifest, manifest with +2.00-D add, and habitual with +2.00-D add (6-month visit only). At baseline, accommodative lag was higher (1.72 ± 0.37 D; mean ± SD) when measured with manifest correction than with habitual correction (1.51 ± 0.50; P < 0.05). This higher lag with manifest correction correlated with a larger amount of habitual undercorrection at baseline (r = -0.29, P = 0.009). A +2.00-D add over the manifest correction reduced lag by 0.45 ± 0.34 D at baseline and 0.33 ± 0.38 D at the 6-month visit. Lag results at 6 months were not different between PAL and SVL wearers (P = 0.92). A +2.00-D bifocal add did not eliminate accommodative lag and reduced lag by less than 25% of the bifocal power, indicating that children mainly responded to a bifocal by decreasing accommodation. If myopic progression is substantial, measuring lag with full correction can overestimate the hyperopic retinal blur that a child most recently experienced. (ClinicalTrials.gov number, NCT00335049.).

  16. The Effect of Bifocal Add on Accommodative Lag in Myopic Children with High Accommodative Lag

    PubMed Central

    Mutti, Donald O.; Zadnik, Karla

    2010-01-01

    Purpose. To determine the effect of a bifocal add and manifest correction on accommodative lag in myopic children with high accommodative lag, who have been reported to have the greatest reduction in myopia progression with progressive addition lenses (PALs). Methods. Monocular accommodative lag to a 4-D Badal stimulus was measured on two occasions 6 months apart in 83 children (mean ± SD age, 9.9 ± 1.3 years) with high lag randomized to wearing single-vision lenses (SVLs) or PALs. Accommodative lag was measured with the following corrections: habitual, manifest, manifest with +2.00-D add, and habitual with +2.00-D add (6-month visit only). Results. At baseline, accommodative lag was higher (1.72 ± 0.37 D; mean ± SD) when measured with manifest correction than with habitual correction (1.51 ± 0.50; P < 0.05). This higher lag with manifest correction correlated with a larger amount of habitual undercorrection at baseline (r = −0.29, P = 0.009). A +2.00-D add over the manifest correction reduced lag by 0.45 ± 0.34 D at baseline and 0.33 ± 0.38 D at the 6-month visit. Lag results at 6 months were not different between PAL and SVL wearers (P = 0.92). Conclusions. A +2.00-D bifocal add did not eliminate accommodative lag and reduced lag by less than 25% of the bifocal power, indicating that children mainly responded to a bifocal by decreasing accommodation. If myopic progression is substantial, measuring lag with full correction can overestimate the hyperopic retinal blur that a child most recently experienced. (ClinicalTrials.gov number, NCT00335049.) PMID:20688729

  17. Stimulating human accommodation without changes in focus.

    PubMed

    Weiss, Monika; Seidemann, Anne; Schaeffel, Frank

    2004-05-01

    Inspired by the finding in chickens that preferential stimulation of the ON retinal system suppresses myopia induced by negative spectacle lens wear and that stimulation of the OFF system suppresses the hyperopia induced by positive lens wear, we sought to determine whether stimulation of the ON-OFF retinal systems could drive directional accommodation responses in humans. If emmetropisation and accommodation use similar image processing algorithms, more accommodation would be expected with OFF stimulation. Accommodation responses were measured while viewing a computer-generated pattern designed to stimulate the ON-OFF systems. The stimulus comprised a rectangular field (12 x 9.5 cm) on a black background filled with 196 discs (diameters: 0.4-1.0 cm). These were presented on an LCD monitor in a dark room at a viewing distance of 55 cm (1.8 D). Thirteen subjects aged 21-37 years took part. The individual discs had saw-tooth shaped temporal luminance profiles with the same time period but with random phases with respect to each other, so that the mean brightness of the stimulus was constant. To eliminate accommodation responses based on other cues (i.e. proximity) a 0.5 mm artificial pupil was used to open the accommodation loop. Refraction in the vertical pupil meridian was continuously recorded with an infrared photorefractor (the PowerRefractor). To verify that computer-based stimuli presented within our experimental design were effective in driving accommodation, previously studied stimuli were also tested: changes in size (looming) and incremental low pass filtering. Preferential stimulation of the ON or OFF subsystems produced a convincing depth illusion in all subjects (which was psychophysically confirmed in four subjects). Although the stimulus appeared to move in depth it did not produce accommodation responses that were consistent with that, i.e. the accommodation system did not appear to fluctuate in rhythm with the temporal oscillations of the stimulus

  18. Visual accommodation trainer-tester

    NASA Technical Reports Server (NTRS)

    Randle, Robert J. (Inventor)

    1988-01-01

    An apparatus for training the human visual accommodation system is described. Specifically, the apparatus is useful for training personnel to volitionally control focus to the far point (normally infinity) from a position of myopia due to functional causes. The functional causes could be due, for example, to a behavioral accommodative spasm or the effects of an empty field. The device may also be used to measure accommodation, the accommodation resting position and the near and far points of vision. The device comprises a number of optical elements arranged on a single optical axis. Several of the elements are arranged in order on a movable stage in fixed relationship to each other: a light source, a lens, a target, an aperture and/or a second lens. On a base and in fixed relationship to each other are eyepiece and third lens. A stage generates an image of the target and the stage is movable with respect to the base by means of a knob. The device is utilized for the various training and test functions by following a series of procedural steps, and interchanging the apertures as necessary for the selected procedure.

  19. δ44/40Ca variability in shallow water carbonates and the impact of submarine groundwater discharge on Ca-cycling in marine environments

    NASA Astrophysics Data System (ADS)

    Holmden, C.; Papanastassiou, D. A.; Blanchon, P.; Evans, S.

    2012-04-01

    local-scale Ca-inputs from SGD, which has a high Ca concentration (450 mg/L) and low δ44/40Ca value (-0.96‰). Mixing calculations show that Ca inputs from SGD and surface water runoff from the Florida Everglades contribute between 8% and 60% of the dissolved Ca to the studied waters with salinities between 30 and 14, respectively. Similar degrees of circulation restriction between epeiric seas and oceans in the geological past may have also led to overprinting of sedimentary carbonate δ44/40Ca values in nearshore regions of epeiric seas due to local-scale cycling of seawater through coastal carbonate aquifers. Local Ca-cycling effects may explain some of the scatter in δ44/40Ca values present in the Ca-isotope evolution curve of Phanerozoic oceans.

  20. Dynamic accommodation responses following adaptation to defocus.

    PubMed

    Cufflin, Matthew P; Mallen, Edward A H

    2008-10-01

    Adaptation to defocus is known to influence the subjective sensitivity to blur in both emmetropes and myopes. Blur is a major contributing factor in the closed-loop dynamic accommodation response. Previous investigations have examined the magnitude of the accommodation response following blur adaptation. We have investigated whether a period of blur adaptation influences the dynamic accommodation response to step and sinusoidal changes in target vergence. Eighteen subjects (six emmetropes, six early onset myopes, and six late onset myopes) underwent 30 min of adaptation to 0.00 D (control), +1.00 D or +3.00 D myopic defocus. Following this adaptation period, accommodation responses to a 2.00 D step change and 2.00 D sinusoidal change (0.2 Hz) in target vergence were recorded continuously using an autorefractor. Adaptation to defocus failed to influence accommodation latency times, but did influence response times to a step change in target vergence. Adaptation to both +1.00 and +3.00 D induced significant increases in response times (p = 0.002 and p = 0.012, respectively) and adaptation to +3.00 D increased the change in accommodation response magnitude (p = 0.014) for a 2.00 D step change in demand. Blur adaptation also significantly increased the peak-to-peak phase lag for accommodation responses to a sinusoidally oscillating target, although failed to influence the accommodation gain. These changes in accommodative response were equivalent across all refractive groups. Adaptation to a degraded stimulus causes an increased level of accommodation for dynamic targets moving towards an observer and increases response times and phase lags. It is suggested that the contrast constancy theory may explain these changes in dynamic behavior.

  1. 46 CFR 169.317 - Accommodations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... of the stem. The space must not be located totally below the deepest load waterline. (b) Bulkheads separating accommodations from machinery spaces, paint lockers, storerooms, washrooms, and toilet facilities... and Arrangement Living Spaces § 169.317 Accommodations. (a) Quarters must have sufficient fresh air...

  2. 46 CFR 169.317 - Accommodations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... of the stem. The space must not be located totally below the deepest load waterline. (b) Bulkheads separating accommodations from machinery spaces, paint lockers, storerooms, washrooms, and toilet facilities... and Arrangement Living Spaces § 169.317 Accommodations. (a) Quarters must have sufficient fresh air...

  3. 46 CFR 169.317 - Accommodations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... of the stem. The space must not be located totally below the deepest load waterline. (b) Bulkheads separating accommodations from machinery spaces, paint lockers, storerooms, washrooms, and toilet facilities... and Arrangement Living Spaces § 169.317 Accommodations. (a) Quarters must have sufficient fresh air...

  4. 46 CFR 169.317 - Accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Accommodations. 169.317 Section 169.317 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Construction and Arrangement Living Spaces § 169.317 Accommodations. (a) Quarters must have sufficient fresh air...

  5. 46 CFR 169.317 - Accommodations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Accommodations. 169.317 Section 169.317 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Construction and Arrangement Living Spaces § 169.317 Accommodations. (a) Quarters must have sufficient fresh air...

  6. Accommodation to wavefront vergence and chromatic aberration.

    PubMed

    Wang, Yinan; Kruger, Philip B; Li, James S; Lin, Peter L; Stark, Lawrence R

    2011-05-01

    Longitudinal chromatic aberration (LCA) provides a cue to accommodation with small pupils. However, large pupils increase monochromatic aberrations, which may obscure chromatic blur. In this study, we examined the effect of pupil size and LCA on accommodation. Accommodation was recorded by infrared optometer while observers (nine normal trichromats) viewed a sinusoidally moving Maltese cross target in a Badal stimulus system. There were two illumination conditions: white (3000 K; 20 cd/m) and monochromatic (550 nm with 10 nm bandwidth; 20 cd/m) and two artificial pupil conditions (3 and 5.7 mm). Separately, static measurements of wavefront aberration were made with the eye accommodating to targets between 0 and 4 D (COAS, Wavefront Sciences). Large individual differences in accommodation to wavefront vergence and to LCA are a hallmark of accommodation. LCA continues to provide a signal at large pupil sizes despite higher levels of monochromatic aberrations. Monochromatic aberrations may defend against chromatic blur at high spatial frequencies, but accommodation responds best to optical vergence and to LCA at 3 c/deg where blur from higher order aberrations is less.

  7. Anthropometric accommodation in USAF cockpits

    NASA Technical Reports Server (NTRS)

    Zehner, Gregory F.

    1994-01-01

    Over the past three years, a new set of methodologies has been developed to specify and evaluate anthropometric accommodation in USAF crewstation designs. These techniques are used to improve the ability of the pilot to reach controls, to safely escape the aircraft, to achieve adequate mobility and comfort, and to assure full access to the visual field both inside and outside the aircraft. This paper summarized commonly encountered aircraft accommodation problems, explains the failure of the traditional 'percentile man' design concept to resolve these difficulties, and suggests an alternative approach for improving cockpit design to better accommodate today's more heterogeneous flying population.

  8. Hydrocarbons identified in extracts from estuarine water accommodated no. 2 fuel oil by gas chromatography-mass spectrometry

    NASA Technical Reports Server (NTRS)

    Lewis, B. W.; Walker, A. L.; Bieri, R. H.

    1974-01-01

    Results are presented on a computerized gas chromatograph-mass spectrometer analysis of methylene chloride and n-heptane extracts of a No. 2 fuel oil accommodated estuarine water sample. The analytical method is briefly described, and the limitations on the identifications are categorized. Some attempt was made to determine major and trace constituents in the water accommodate. Altogether 66 hydrocarbon compounds were identified specifically, and 75 compounds were partially identified. Seven compounds could be recognized as major constituents of the water accommodated oil and ten were present only as traces. The aromatic compounds found were alkyl benzenes, naphthalene, tetralin, indane, biphenyl, fluorene, anthracene, and some of their alkyl substituted isomers in the range of carbon numbers C7 to C15. Four n-alkanes, C10 to C13, were found along with four other assorted hydrocarbons.

  9. A Review of Worksite Lactation Accommodations.

    PubMed

    Hilliard, Elizabeth Dianne

    2017-01-01

    The purpose of this review was to examine workplace lactation accommodations, and their association with breastfeeding duration, and identify strategies occupational health professionals can use to promote lactation improvements. This study included literature published from 1985 through 2015 and listed in PubMed and CINAHL. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), 11 articles were identified for review. Presence of a corporate lactation program, on-site child care, and return to work/telephone lactation consultation were consistently associated with breastfeeding at 6 months. Other breastfeeding accommodations (i.e., lactation spaces, lactation breaks, worksite lactation policies, and supervisor/coworker support) were not consistently associated with breastfeeding duration. Occupational health professionals can play key roles in improving the effectiveness of lactation accommodations. Assuring adequate implementation of accommodations, increasing communication and marketing of accommodations, and promoting supervisor and coworker support are areas that occupational health professionals should explore for improving lactation duration.

  10. Exploring the Relationship Between Students Needing Accommodations and Instructor Self-Efficacy in Complying with Accommodations

    ERIC Educational Resources Information Center

    Wright, Anna M.; Meyer, Kevin R.

    2017-01-01

    The willingness and flexibility of university instructors to comply with and provide accommodations for students with disabilities is critical to academic success. The authors examine how communication between students needing accommodations and university instructors impacts instructor self-efficacy, or instructors' perception that they can meet…

  11. Accommodative spasm in siblings: A unique finding

    PubMed Central

    Rutstein, Robert P

    2010-01-01

    Accommodative spasm is a rare condition occurring in children, adolescents, and young adults. A familial tendency for this binocular vision disorder has not been reported. I describe accommodative spasm occurring in a brother and sister. Both children presented on the same day with complaints of headaches and blurred vision. Treatment included cycloplegia drops and bifocals. Siblings of patients having accommodative spasm should receive a detailed eye exam with emphasis on recognition of accommodative spasm. PMID:20534925

  12. Accommodation, accommodative convergence, and response AC/A ratios before and at the onset of myopia in children.

    PubMed

    Gwiazda, Jane; Thorn, Frank; Held, Richard

    2005-04-01

    The purpose of this study was to investigate accommodation, accommodative convergence, and AC/A ratios before and at the onset of myopia in children. Refractive error, accommodation, and phorias were measured annually over a period of 3 years in 80 6- to 18-year-old children (mean age at first visit = 11.1 years), including 26 who acquired myopia of at least -0.50 D and 54 who remained emmetropic (-0.25 to + 0.75 D). Refraction was measured by noncycloplegic distance retinoscopy. Concomitant measures of accommodation and phorias were taken for letter targets at 4.0 m and 0.33 m using the Canon R-1 open field-of-view autorefractor with an attached motorized Risley prism and Maddox rod. The accommodation and phoria measurements were used to calculate response AC/A ratios. Compared with children who remained emmetropic, those who became myopic had elevated response AC/A ratios at 1 and 2 years before the onset of myopia, in addition to at onset and 1 year later (t's = -2.97 to -4.04, p < 0.01 at all times). The significantly higher AC/A ratios in the children who became myopic are a result of significantly reduced accommodation. Accommodative convergence was significantly greater in myopes only at onset. These findings suggest that the abnormal oculomotor factors found before the onset of myopia may contribute to myopigenesis by producing hyperopic retinal defocus when a child is engaged in near-viewing tasks.

  13. Accommodative Performance of Children With Unilateral Amblyopia

    PubMed Central

    Manh, Vivian; Chen, Angela M.; Tarczy-Hornoch, Kristina; Cotter, Susan A.; Candy, T. Rowan

    2015-01-01

    Purpose. The purpose of this study was to compare the accommodative performance of the amblyopic eye of children with unilateral amblyopia to that of their nonamblyopic eye, and also to that of children without amblyopia, during both monocular and binocular viewing. Methods. Modified Nott retinoscopy was used to measure accommodative performance of 38 subjects with unilateral amblyopia and 25 subjects with typical vision from 3 to 13 years of age during monocular and binocular viewing at target distances of 50, 33, and 25 cm. The relationship between accommodative demand and interocular difference (IOD) in accommodative error was assessed in each group. Results. The mean IOD in monocular accommodative error for amblyopic subjects across all three viewing distances was 0.49 diopters (D) (95% confidence interval [CI], ±1.12 D) in the 180° meridian and 0.54 D (95% CI, ±1.27 D) in the 90° meridian, with the amblyopic eye exhibiting greater accommodative errors on average. Interocular difference in monocular accommodative error increased significantly with increasing accommodative demand; 5%, 47%, and 58% of amblyopic subjects had monocular errors in the amblyopic eye that fell outside the upper 95% confidence limit for the better eye of control subjects at viewing distances of 50, 33, and 25 cm, respectively. Conclusions. When viewing monocularly, children with unilateral amblyopia had greater mean accommodative errors in their amblyopic eyes than in their nonamblyopic eyes, and when compared with control subjects. This could lead to unintended retinal image defocus during patching therapy for amblyopia. PMID:25626970

  14. 46 CFR 108.211 - Miscellaneous accommodation spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Miscellaneous accommodation spaces. 108.211 Section 108... DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.211 Miscellaneous accommodation spaces. (a) Each unit must have enough facilities for personnel to wash their own clothes...

  15. 46 CFR 108.211 - Miscellaneous accommodation spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Miscellaneous accommodation spaces. 108.211 Section 108... DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.211 Miscellaneous accommodation spaces. (a) Each unit must have enough facilities for personnel to wash their own clothes...

  16. 46 CFR 108.211 - Miscellaneous accommodation spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Miscellaneous accommodation spaces. 108.211 Section 108... DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.211 Miscellaneous accommodation spaces. (a) Each unit must have enough facilities for personnel to wash their own clothes...

  17. 46 CFR 108.211 - Miscellaneous accommodation spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Miscellaneous accommodation spaces. 108.211 Section 108... DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.211 Miscellaneous accommodation spaces. (a) Each unit must have enough facilities for personnel to wash their own clothes...

  18. 46 CFR 108.211 - Miscellaneous accommodation spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Miscellaneous accommodation spaces. 108.211 Section 108... DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.211 Miscellaneous accommodation spaces. (a) Each unit must have enough facilities for personnel to wash their own clothes...

  19. Employer Accommodation and Labor Supply of Disabled Workers*

    PubMed Central

    Hill, Matthew J.; Maestas, Nicole; Mullen, Kathleen J.

    2016-01-01

    We examine the factors that influence employer accommodation of newly disabled workers and how effective such accommodations are in retaining workers and discouraging disability insurance applications. Using the Health and Retirement Study, we find that only a quarter of newly disabled older workers in their 50s are accommodated by their employers in some way following onset of a disability. Importantly, we find that few employer characteristics explain which workers are accommodated; rather, employee characteristics, particularly the presence of personality traits correlated with assertiveness and open communication, are highly predictive of accommodation. We also find that if employer accommodation rates could be increased, disabled workers would be significantly more likely to delay labor force exit for up to two years. However, accommodation does not appear to reduce subsequent disability insurance claiming. PMID:27840560

  20. 46 CFR 108.195 - Location of accommodation spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Location of accommodation spaces. 108.195 Section 108... DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.195 Location of accommodation spaces. (a) On surface type units, accommodation spaces must not be located forward of a vertical...

  1. 46 CFR 108.195 - Location of accommodation spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Location of accommodation spaces. 108.195 Section 108... DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.195 Location of accommodation spaces. (a) On surface type units, accommodation spaces must not be located forward of a vertical...

  2. 46 CFR 108.195 - Location of accommodation spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Location of accommodation spaces. 108.195 Section 108... DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.195 Location of accommodation spaces. (a) On surface type units, accommodation spaces must not be located forward of a vertical...

  3. 46 CFR 108.195 - Location of accommodation spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Location of accommodation spaces. 108.195 Section 108... DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.195 Location of accommodation spaces. (a) On surface type units, accommodation spaces must not be located forward of a vertical...

  4. 46 CFR 108.195 - Location of accommodation spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Location of accommodation spaces. 108.195 Section 108... DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.195 Location of accommodation spaces. (a) On surface type units, accommodation spaces must not be located forward of a vertical...

  5. Accommodation to Wavefront Vergence and Chromatic Aberration

    PubMed Central

    Wang, Yinan; Kruger, Philip B.; Li, James S.; Lin, Peter L.; Stark, Lawrence R.

    2011-01-01

    Purpose Longitudinal chromatic aberration (LCA) provides a cue to accommodation with small pupils. However, large pupils increase monochromatic aberrations, which may obscure chromatic blur. In the present study, we examined the effect of pupil size and LCA on accommodation. Methods Accommodation was recorded by infrared optometer while observers (nine normal trichromats) viewed a sinusoidally moving Maltese cross target in a Badal stimulus system. There were two illumination conditions: white (3000 K; 20 cd/m2) and monochromatic (550 nm with 10 nm bandwidth; 20 cd/m2) and two artificial pupil conditions (3 mm and 5.7 mm). Separately, static measurements of wavefront aberration were made with the eye accommodating to targets between 0 and 4 D (COAS, Wavefront Sciences). Results Large individual differences in accommodation to wavefront vergence and to LCA are a hallmark of accommodation. LCA continues to provide a signal at large pupil sizes despite higher levels of monochromatic aberrations. Conclusions Monochromatic aberrations may defend against chromatic blur at high spatial frequencies, but accommodation responds best to optical vergence and to LCA at 3 c/deg where blur from higher order aberrations is less. PMID:21317666

  6. Reproducibility of carbachol stimulated accommodation in rhesus monkeys.

    PubMed

    Wendt, Mark; Glasser, Adrian

    2012-06-01

    Approaches are being explored to restore accommodation to the presbyopic eye. Some of these approaches can be tested in monkeys by stimulating accommodation in various ways including using carbachol iontophoresis. Knowledge of the repeatability of carbachol iontophoresis stimulated accommodation in the monkey phakic eye is necessary to understand the variability of this method of evaluating accommodation. Data from 9 to 10 separate carbachol iontophoresis experiments performed on phakic eyes from 8 monkeys were retrospectively analyzed. For each experiment, carbachol was applied iontophoretically to the eyes of anesthetized monkeys and refraction generally measured every two minutes until accommodation reached a plateau. Repeated experiments were performed in each monkey over periods ranging from 10 to 18 months. Maximum accommodation measured for each monkey ranged from 11.1 D to 18.3 D with standard deviations from 0.8 D to 2.1 D and differences in accommodative amplitude varying from 2.2 D to 7.5 D. Time to reach maximum accommodation ranged from 18 to 64 min in individual experiments. Averaged time-courses indicate that maximum accommodation is generally achieved between 10 and 20 min after carbachol administration. Although carbachol iontophoresis is considered a reliable method to stimulate maximum accommodation in anesthetized monkeys, the amplitude achieved typically varies by more than 2 D. Presbyopia treatments evaluated in this way in phakic monkeys would need to show an increase in accommodation of over 2 D to clearly demonstrate that the treatments work when being tested with carbachol iontophoresis stimulation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Accommodation in Astigmatic Children During Visual Task Performance

    PubMed Central

    Harvey, Erin M.; Miller, Joseph M.; Apple, Howard P.; Parashar, Pavan; Twelker, J. Daniel; Crescioni, Mabel; Davis, Amy L.; Leonard-Green, Tina K.; Campus, Irene; Sherrill, Duane L.

    2014-01-01

    Purpose. To determine the accuracy and stability of accommodation in uncorrected children during visual task performance. Methods. Subjects were second- to seventh-grade children from a highly astigmatic population. Measurements of noncycloplegic right eye spherical equivalent (Mnc) were obtained while uncorrected subjects performed three visual tasks at near (40 cm) and distance (2 m). Tasks included reading sentences with stimulus letter size near acuity threshold and an age-appropriate letter size (high task demands) and viewing a video (low task demand). Repeated measures ANOVA assessed the influence of astigmatism, task demand, and accommodative demand on accuracy (mean Mnc) and variability (mean SD of Mnc) of accommodation. Results. For near and distance analyses, respectively, sample size was 321 and 247, mean age was 10.37 (SD 1.77) and 10.30 (SD 1.74) years, mean cycloplegic M was 0.48 (SD 1.10) and 0.79 diopters (D) (SD 1.00), and mean astigmatism was 0.99 (SD 1.15) and 0.75 D (SD 0.96). Poor accommodative accuracy was associated with high astigmatism, low task demand (video viewing), and high accommodative demand. The negative effect of accommodative demand on accuracy increased with increasing astigmatism, with the poorest accommodative accuracy observed in high astigmats (≥3.00 D) with high accommodative demand/high hyperopia (1.53 D and 2.05 D of underaccommodation for near and distant stimuli, respectively). Accommodative variability was greatest in high astigmats and was uniformly high across task condition. No/low and moderate astigmats showed higher variability for the video task than the reading tasks. Conclusions. Accuracy of accommodation is reduced in uncorrected children with high astigmatism and high accommodative demand/high hyperopia, but improves with increased visual task demand (reading). High astigmats showed the greatest variability in accommodation. PMID:25103265

  8. Decreased accommodation during decompensation of distance exotropia.

    PubMed

    Horwood, Anna M; Riddell, Patricia M

    2012-04-01

    Disparity cues can be a major drive to accommodation via the convergence accommodation to convergence (CA/C) linkage, but, on decompensation of exotropia, disparity cues are extinguished by suppression so this drive is lost. This study investigated accommodation and vergence responses to disparity, blur and proximal cues in a group of distance exotropes aged between 4 and 11 years both during decompensation and when exotropic. 19 participants with distance exotropia were tested using a PlusoptiXSO4 photo refractor set in a remote haploscopic device that assessed simultaneous vergence and accommodation to a range of targets incorporating different combinations of blur, disparity and proximal cues at four fixation distances between 2 m and 33 cm. Responses on decompensation were compared with those from the same children when their deviation was controlled. Manifest exotropia was more common in the more impoverished cue conditions. When decompensated for near, mean accommodation gain for the all-cue (naturalistic) target was significantly reduced (p<0.0001), with resultant mean under-accommodation of 2.33 D at 33 cm. The profile of near cues usage changed after decompensation, with blur and proximity driving residual responses, but these remaining cues did not compensate for loss of accommodation caused by the removal of disparity. Accommodation often reduces on decompensation of distance exotropia as the drive from convergence is extinguished, providing a further reason to try to prevent decompensation for near.

  9. Decreased accommodation during decompensation of distance exotropia

    PubMed Central

    Horwood, Anna M; Riddell, Patricia M

    2015-01-01

    Objective Disparity cues can be a major drive to accommodation via the CA/C (convergence accommodation to convergence) linkage but, on decompensation of exotropia, disparity cues are extinguished by suppression, so this drive is lost. This study investigated accommodation and vergence responses to disparity, blur and proximal cues in a group of distance exotropes aged between 4-11 years both during decompensation and when exotropic. Methods 19 participants with distance exotropia were tested using a PlusoptiXSO4 photorefractor set in a remote haploscopic device which assessed simultaneous vergence and accommodation to a range of targets incorporating different combinations of blur, disparity and proximal cues at four fixation distances between 2m and 33cm. Responses on decompensation were compared to those from the same children when their deviation was controlled. Results Manifest exotropia was more common in the more impoverished cue conditions. When decompensated for near, mean accommodation gain for the all-cue (naturalistic) target reduced significantly (p<0.0001), with resultant mean under-accommodation of 2.33D at 33cm. The profile of near cues usage changed after decompensation, with blur and proximity driving residual responses, but these remaining cues did not compensate for loss of accommodation caused by the removal of disparity. Conclusions Accommodation often reduces on decompensation of distance exotropia as the drive from convergence is extinguished, providing a further reason to try to prevent decompensation for near. PMID:21873311

  10. Effect of Phenylephrine on the Accommodative System

    PubMed Central

    Del Águila-Carrasco, Antonio J.; Bernal-Molina, Paula; Ferrer-Blasco, Teresa; López-Gil, Norberto; Montés-Micó, Robert

    2016-01-01

    Accommodation is controlled by the action of the ciliary muscle and mediated primarily by parasympathetic input through postganglionic fibers that originate from neurons in the ciliary and pterygopalatine ganglia. During accommodation the pupil constricts to increase the depth of focus of the eye and improve retinal image quality. Researchers have traditionally faced the challenge of measuring the accommodative properties of the eye through a small pupil and thus have relied on pharmacological agents to dilate the pupil. Achieving pupil dilation (mydriasis) without affecting the accommodative ability of the eye (cycloplegia) could be useful in many clinical and research contexts. Phenylephrine hydrochloride (PHCl) is a sympathomimetic agent that is used clinically to dilate the pupil. Nevertheless, first investigations suggested some loss of functional accommodation in the human eye after PHCl instillation. Subsequent studies, based on different measurement procedures, obtained contradictory conclusions, causing therefore an unexpected controversy that has been spread almost to the present days. This manuscript reviews and summarizes the main research studies that have been performed to analyze the effect of PHCl on the accommodative system and provides clear conclusions that could help clinicians know the real effects of PHCl on the accommodative system of the human eye. PMID:28053778

  11. Teleworkers with disabilities: characteristics and accommodation use.

    PubMed

    Linden, Maureen; Milchus, Karen

    2014-01-01

    The prevalence of telework among people with disabilities is not as great as the general population, despite the accommodative benefits of telework. This study of employment and accommodation use patterns of people with disabilities investigates relationships between functional abilities, work location and nature, and accommodation use. Currently employed subjects with disabilities were recruited from client lists of research, technical assistance, and service provision centers, as well as through over 100 social networking venues focused on individuals with disabilities. A national, cross-sectional survey was administered electronically. Details of accommodation use for 373 individuals were compared using Chi-Square distribution analysis. Those in white-collar and knowledge-based jobs were twice as likely to telework as other worker types, and teleworkers were twice as likely to use flexible scheduling. Only 47% of teleworkers reported telework as a job accommodation. Of those, 57% were satisfied with telework and 76% reported it as important to job task completion. Increased use of flexible scheduling, particularly among those who view telework as an accommodation, suggests the primary accommodative benefit of telework is to reduce pain and fatigue-related barriers to traditional employment. Relatively low satisfaction with telework suggests that it presents other employment-related barriers.

  12. Surface accommodation of molecular contaminants

    NASA Technical Reports Server (NTRS)

    Chen, Philip T.; Hedgeland, Randy J.; Thomson, Shaun R.

    1990-01-01

    Theoretical consideration and supporting data are presented regarding the nature of the transport mechanisms which cause the adsorption of gases on spacecraft surfaces. Particular attention is given to the concept of a sticking coefficient which is the ratio of the thermally accommodated mass to the total incident mass. Existing molecular accommodation data are examined in terms of spacecraft applications and recent contamination-control data are introduced. Two distinct yet linked concepts emerge which are the accommodation and sticking coefficients, and surface roughness contributes significantly to both coefficients. A general equation regarding the coefficients is developed, and the data are found to fit the equation basically. It is concluded that a more precise characterization of the coefficients can be obtained through experimentation under simulated spacecraft conditions.

  13. Advanced Solar Observatory (ASO) accommodations requirements study

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Results of an accommodations analysis for the Advanced Solar Observatory on Space Station Freedom are reported. Concepts for the High Resolution Telescope Cluster, Pinhole/Occulter Facility, and High Energy Cluster were developed which can be accommodated on Space Station Freedom. It is shown that workable accommodations concepts are possible. Areas of emphasis for the next stage of engineering development are identified.

  14. 77 FR 38833 - Job Accommodation Network

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-29

    ... DEPARTMENT OF LABOR Job Accommodation Network AGENCY: Office of Disability Employment Policy, Department of Labor. Announcement Type: New Notice of Availability of Funds and Solicitation for Grant... cooperative agreement to manage and operate its Job Accommodation Network (JAN), a national technical...

  15. Gender differences in early accommodation and vergence development.

    PubMed

    Horwood, Anna M; Riddell, Patricia M

    2008-03-01

    A remote haploscopic photorefractor was used to assess objective binocular vergence and accommodation responses in 157 full-term healthy infants aged 1-6 months while fixating a brightly coloured target moving between fixation distances at 2, 1, 0.5 and 0.33 m. Vergence and accommodation response gain matured rapidly from 'flat' neonatal responses at an intercept of approximately 2 dioptres (D) for accommodation and 2.5 metre angles(MA) for vergence, reaching adult-like values at 4 months. Vergence gain was marginally higher in females (p = 0.064), but accommodation gain (p = 0.034) was higher and accommodative intercept closer to zero (p = 0.004) in males in the first 3 months as they relaxed accommodation more appropriately for distant targets. More females showed flat accommodation responses (p = 0.029). More males behaved hypermetropically in the first two months of life, but when these hypermetropic infants were excluded from the analysis, the gender difference remained. Gender differences disappeared after three months. Data showed variable responses and infants could behave appropriately and simultaneously on both, neither or only one measure at all ages. If accommodation was appropriate (gain between 0.7 and 1.3; r(2) > 0.7) but vergence was not, males over- and under-converged equally, while the females who accommodated appropriately were more likely to overconverge (p = 0.008). The apparent earlier maturity of the male accommodative responses may be due to refractive error differences but could also reflect gender-specific male preference for blur cues while females show earlier preference for disparity, which may underpin the earlier emerging, disparity dependent, stereopsis and full vergence found in females in other studies.

  16. Chromatic aberration, accommodation, and color preference in asthenopia.

    PubMed

    Drew, Stefanie A; Borsting, Eric; Stark, Lawrence R; Chase, Chris

    2012-07-01

    Asthenopia is a common problem associated with near work and reports suggest that colored lenses or overlays may be applied to reduce symptoms. In this study, we examine the relationship between eyestrain, color preferences, and function of the accommodation and vergence system. Specifically, we examine whether symptomatic observers select colors that reduce accommodative demand based on longitudinal chromatic aberration (LCA). Forty-seven undergraduate students participated in this study. Visual discomfort symptoms were assessed using the Conlon survey. A Mark 2 Intuitive Colorimeter was used to obtain optimal colored light preferences. LCA was modeled using the Chromatic Eye and spectral power density data. A comprehensive evaluation of accommodation and vergence was performed following standard procedures. A significant negative correlation (r = -0.51) was found between eyestrain symptoms and the International Commission on Illumination (CIE) v' axis of colors preferences. Additionally, a significant negative correlation (r = -0.31) was found between eyestrain symptoms and LCA accommodation. Two thirds of the participants in the high discomfort group chose colors that decreased accommodative demand. Accommodative amplitude and vergence facility also correlated with LCA, accounting for 25% of the variance. The color preferences of individuals are systematically influenced by the functioning of their accommodation and vergence systems with increased symptomatology resulting in color selections that reduce LCA accommodative stimulus demand.

  17. Adaptive Calibration of Dynamic Accommodation—Implications for Accommodating Intraocular Lenses

    PubMed Central

    Schor, Clifton M.; Bharadwaj, Shrikant R.

    2009-01-01

    PURPOSE When the aging lens is replaced with prosthetic accommodating intraocular lenses (IOLs), with effective viscoelasticities different from those of the natural lens, mismatches could arise between the neural control of accommodation and the biomechanical properties of the new lens. These mismatches could lead to either unstable oscillations or sluggishness of dynamic accommodation. Using computer simulations, we investigated whether optimal accommodative responses could be restored through recalibration of the neural control of accommodation. Using human experiments, we also investigated whether the accommodative system has the capacity for adaptive recalibration in response to changes in lens biomechanics. METHODS Dynamic performance of two accommodating IOL prototypes was simulated for a 45-year-old accommodative system, before and after neural recalibration, using a dynamic model of accommodation. Accommodating IOL I, a prototype for an injectable accommodating IOL, was less stiff and less viscous than the natural 45-year-old lens. Accommodating IOL II, a prototype for a translating accommodating IOL, was less stiff and more viscous than the natural 45-year-old lens. Short-term adaptive recalibration of dynamic accommodation was stimulated using a double-step adaptation paradigm that optically induced changes in neuromuscular effort mimicking responses to changes in lens biomechanics. RESULTS Model simulations indicate that the unstable oscillations or sluggishness of dynamic accommodation resulting from mismatches between neural control and lens biomechanics might be restored through neural recalibration. CONCLUSIONS Empirical measures reveal that the accommodative system is capable of adaptive recalibration in response to optical loads that simulate effects of changing lens biomechanics. PMID:19044245

  18. 14 CFR 1251.201 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... OF HANDICAP Employment Practices § 1251.201 Reasonable accommodation. (a) A recipient shall make reasonable accommodation to the known physical or mental limitations of an otherwise qualified handicapped... facilities used by employees readily accessible to and usable by handicapped persons; and (2) Job...

  19. 14 CFR 1251.201 - Reasonable accommodation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... OF HANDICAP Employment Practices § 1251.201 Reasonable accommodation. (a) A recipient shall make reasonable accommodation to the known physical or mental limitations of an otherwise qualified handicapped... facilities used by employees readily accessible to and usable by handicapped persons; and (2) Job...

  20. 14 CFR 1251.201 - Reasonable accommodation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... OF HANDICAP Employment Practices § 1251.201 Reasonable accommodation. (a) A recipient shall make reasonable accommodation to the known physical or mental limitations of an otherwise qualified handicapped... facilities used by employees readily accessible to and usable by handicapped persons; and (2) Job...

  1. 14 CFR 1251.201 - Reasonable accommodation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... OF HANDICAP Employment Practices § 1251.201 Reasonable accommodation. (a) A recipient shall make reasonable accommodation to the known physical or mental limitations of an otherwise qualified handicapped... facilities used by employees readily accessible to and usable by handicapped persons; and (2) Job...

  2. Experimental investigations of pupil accommodation factors.

    PubMed

    Lee, Eui Chul; Lee, Ji Woo; Park, Kang Ryoung

    2011-08-17

    PURPOSE. The contraction and dilation of the iris muscle that controls the amount of light entering the retina causes pupil accommodation. In this study, experiments were performed and two of the three factors that influence pupil accommodation were analyzed: lighting conditions and depth fixations. The psychological benefits were not examined, because they could not be quantified. METHODS. A head-wearable eyeglasses-based, eye-capturing device was designed to measure pupil size. It included a near-infrared (NIR) camera and an NIR light-emitting diode. Twenty-four subjects watched two-dimensional (2D) and three-dimensional (3D) stereoscopic videos of the same content, and the changes in pupil size were measured by using the eye-capturing device and image-processing methods: RESULTS. The pupil size changed with the intensity of the videos and the disparities between the left and right images of a 3D stereoscopic video. There was correlation between the pupil size and average intensity. The pupil diameter could be estimated as being contracted from approximately 5.96 to 4.25 mm as the intensity varied from 0 to 255. Further, from the changes in the depth fixation for the pupil accommodation, it was confirmed that the depth fixation also affected accommodation of pupil size. CONCLUSIONS. It was confirmed that the lighting condition was an even more significant factor in pupil accommodation than was depth fixation (significance ratio: approximately 3.2:1) when watching 3D stereoscopic video. Pupil accommodation was more affected by depth fixation in the real world than was the binocular convergence in the 3D stereoscopic display.

  3. Acceleration characteristics of human ocular accommodation.

    PubMed

    Bharadwaj, Shrikant R; Schor, Clifton M

    2005-01-01

    Position and velocity of accommodation are known to increase with stimulus magnitude, however, little is known about acceleration properties. We investigated three acceleration properties: peak acceleration, time-to-peak acceleration and total duration of acceleration to step changes in defocus. Peak velocity and total duration of acceleration increased with response magnitude. Peak acceleration and time-to-peak acceleration remained independent of response magnitude. Independent first-order and second-order dynamic components of accommodation demonstrate that neural control of accommodation has an initial open-loop component that is independent of response magnitude and a closed-loop component that increases with response magnitude.

  4. Overview for Attached Payload Accommodations and Environments

    NASA Technical Reports Server (NTRS)

    Schaffer, Craig; Cook, Gene; Nabizadeh, Rodney; Phillion, James

    2007-01-01

    External payload accommodations are provided at attach sites on the U.S provided ELC, U.S. Truss, the Japanese Experiment Module Exposed Facility (JEM EF) and the Columbus EPF (External Payload Facilities). The Integrated Truss Segment (ITS) provides the backbone structure for the ISS. It attaches the solar and thermal control arrays to the rest of the complex, and houses cable distribution trays Extravehicular Activity (EVA) support equipment such as handholds and lighting; and providing for Extravehicular Robotic (EVR) accommodations using the Mobile Servicing System (MSS). It also provides logistics and maintenance, and payload attachment sites. The attachment sites accommodate logistics and maintenance and payloads carriers, zenith and nadir. The JEM-EF, a back porch-like attachment to the JEM Pressurized Module, accommodates up to eight payloads, which can be serviced by the crew via the JEM PM's airlock and dedicated robotic arm. The Columbus-EPF is another porch-like platform that can accommodate two zenith and two nadir looking payloads.

  5. Appropriate Accommodations for Individual Needs Allowable by State Guidelines

    ERIC Educational Resources Information Center

    Jordan, Ashley Sokol

    2009-01-01

    Accommodation decisions should be based on the validity and accountability to provide the least restrictive accommodations for students with learning disabilities. Accommodations are based upon the allowable guidelines set by the Ohio Department of Education but the scribing accommodations do not meet the least restrictive criteria for many…

  6. New EEOC guidance details responsibilities for job accommodation.

    PubMed

    1999-04-02

    The Equal Employment Opportunity Commission (EEOC) released new guidelines on how employers should accommodate the needs of workers with disabilities. Guidelines address using leave as an accommodation, the duty of offering reassignment as a form of reasonable accommodation, and an employer's cost of accommodation. Among the clarifications, the EEOC states that employers do not have to provide more paid leave than workers in similar situations receive. Employees must be qualified for reassignments, and the employer is not obligated to provide training for the new position. The EEOC disagrees with the Americans with Disabilities Act reasoning that employers should not be forced to accommodate if a cost-benefit analysis reveals undue hardship on the employer. Contact information is provided.

  7. 46 CFR 177.810 - Overnight accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TONS) CONSTRUCTION AND ARRANGEMENT Passenger Accommodations § 177.810 Overnight accommodations. (a) A... three high and must be constructed of wood, fiber reinforced plastic, or metal. A berth located more... construction and arrangement of berths and other furniture must allow free and unobstructed access to each...

  8. 10 CFR 1040.67 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... known physical or mental limitations of an otherwise qualified handicapped applicant or employee unless the recipient can demonstrate that the accommodation would impose an undue hardship on the operation... accommodation would impose an undue hardship on the operation of a recipient's program or activity, factors to...

  9. 45 CFR 84.12 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... physical or mental limitations of an otherwise qualified handicapped applicant or employee unless the recipient can demonstrate that the accommodation would impose an undue hardship on the operation of its... an accommodation would impose an undue hardship on the operation of a recipient's program or activity...

  10. 45 CFR 1232.10 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... shall make reasonable accommodation to the known physical or mental limitations of an otherwise... accommodation would impose an undue hardship on the operation of its program or activity. (b) Reasonable... would impose an undue hardship on the operation of a recipient's program or activity, factors to be...

  11. 10 CFR 4.123 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... shall make reasonable accommodation to the known physical or mental limitations of an otherwise... would impose an undue hardship on the operation of its program or activity. (b) Reasonable accommodation... on the operation of a recipient's program or activity, factors to be considered include: (1) The...

  12. [Comparison study on subjective and objective measurements of the accommodative convergence to accommodation ratio].

    PubMed

    Xu, Jing-jing; Xu, Dan; Huang, Tao; Jiang, Jian; Lü, Fan

    2012-05-01

    To detect the accommodative convergence to accommodation (AC/A) ratios measured respectively by objective and subjective methods. The differences and its relative factors were explored. Forty young volunteers were measured by eye tracker to get the amount of convergence when fixating at the target at 100 cm, 50 cm, 33 cm and 25 cm and were measured by infrared auto-refractor to get corresponding accommodative responses. AC/A ratio based on these two measurements were compared with the calculated and the gradient AC/A ratio from Von Graefe tests. Mean value of stimulated AC/A ratio measured by eye tracker was higher than the calculated and gradient AC/A ratio by Von Graefe method (P = 0.003, 0.001). There are statistic correlation (r = 0.871, P = 0.000) and difference (P = 0.000) between stimulated AC/A ratio and response AC/A ratios both measured by eye tracker, and the difference trends to be greater with the higher AC/A ratio. The objective AC/A ratio is usually higher than the clinical subjective measurement because of more proximal effect. The response AC/A ratio measured objectively may reveal realistically the mutual effect and relationship between accommodation and convergence and it seems to be more credible to be the monitor parameter on progression of myopia in clinics.

  13. 46 CFR 108.197 - Construction of accommodation spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Construction of accommodation spaces. 108.197 Section... UNITS DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.197 Construction of accommodation spaces. (a) Each sleeping, mess, recreational, or hospital space that is adjacent to or...

  14. 46 CFR 108.197 - Construction of accommodation spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Construction of accommodation spaces. 108.197 Section... UNITS DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.197 Construction of accommodation spaces. (a) Each sleeping, mess, recreational, or hospital space that is adjacent to or...

  15. 46 CFR 108.197 - Construction of accommodation spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Construction of accommodation spaces. 108.197 Section... UNITS DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.197 Construction of accommodation spaces. (a) Each sleeping, mess, recreational, or hospital space that is adjacent to or...

  16. 46 CFR 108.197 - Construction of accommodation spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Construction of accommodation spaces. 108.197 Section... UNITS DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.197 Construction of accommodation spaces. (a) Each sleeping, mess, recreational, or hospital space that is adjacent to or...

  17. 46 CFR 108.197 - Construction of accommodation spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Construction of accommodation spaces. 108.197 Section... UNITS DESIGN AND EQUIPMENT Construction and Arrangement Accommodation Spaces § 108.197 Construction of accommodation spaces. (a) Each sleeping, mess, recreational, or hospital space that is adjacent to or...

  18. Minus-Lens–Stimulated Accommodative Amplitude Decreases Sigmoidally with Age: A Study of Objectively Measured Accommodative Amplitudes from Age 3

    PubMed Central

    Anderson, Heather A.; Hentz, Gloria; Glasser, Adrian; Stuebing, Karla K.; Manny, Ruth E.

    2009-01-01

    Purpose Guidelines for predicting accommodative amplitude by age are often based on subjective push-up test data that overestimate the accommodative response. Studies in which objective measurements were used have defined expected amplitudes for adults, but expected amplitudes for children remain unknown. In this study, objective methods were used to measure accommodative amplitude in a wide age range of individuals, to define the relationship of amplitude and age from age 3. Methods Accommodative responses were measured in 140 subjects aged 3 to 40 years. Measurements were taken with the Grand Seiko autorefractor (RyuSyo Industrial Co., Ltd., Kagawa, Japan) as the subjects viewed a high-contrast target at 33 cm through minus lenses of increasing power until the responses showed no further increase in accommodation. Results The maximum accommodative amplitude of each subject was plotted by age, and a curvilinear function fit to the data: y = 7.33 − 0.0035(age − 3)2 (P < 0.001). Tangent analysis of the fit indicated that the accommodative amplitude remained relatively stable until age 20. Data from this study were then pooled with objective amplitudes from previous studies of adults up to age 70. A sigmoidal function was fit to the data: y = 7.083/(1 + e[0.2031(age-36.2)−0.6109]) (P < 0.001). The sigmoidal function indicated relatively stable amplitudes below age 20 years, a rapid linear decline between 20 and 50 years, and a taper to 0 beyond 50 years. Conclusions These data indicate that accommodative amplitude decreases in a curvilinear manner from 3 to 40 years. When combined with data from previous studies, a sigmoidal function describes the overall trend throughout life with the biggest decrease occurring between 20 and 50 years. PMID:18326693

  19. Long-term follow-up of acute isolated accommodation insufficiency.

    PubMed

    Lee, Jung Jin; Baek, Seung-Hee; Kim, Ungsoo Samuel

    2013-04-01

    To define the long-term results of accommodation insufficiency and to investigate the correlation between accommodation insufficiency and other factors including near point of convergence (NPC), age, and refractive errors. From January 2008 to December 2009, 11 patients with acute near vision disturbance and remote near point of accommodation (NPA) were evaluated. Full ophthalmologic examinations, including best corrected visual acuity, manifest refraction and prism cover tests were performed. Accommodation ability was measured by NPA using the push-up method. We compared accommodation insufficiency and factors including age, refractive errors and NPC. We also investigated the recovery from loss of accommodation in patients. Mean age of patients was 20 years (range, 9 to 34 years). Five of the 11 patients were female. Mean refractive error was -0.6 diopters (range, -3.5 to +0.25 diopters) and 8 of 11 patients (73%) had emmetropia (+0.50 to -0.50 diopters). No abnormalities were found in brain imaging tests. Refractive errors were not correlated with NPA or NPC (rho = 0.148, p = 0.511; rho = 0.319, p = 0.339; respectively). The correlation between age and NPA was not significant (rho = -395, p = 0.069). However, the correlation between age and NPC was negative (rho = -0.508, p = 0.016). Three of 11 patients were lost to follow-up, and 6 of 8 patients had permanent insufficiency of accommodation. Accommodation insufficiency is most common in emmetropia, however, refractive errors and age are not correlated with accommodation insufficiency. Dysfunction of accommodation can be permanent in the isolated accommodation insufficiency.

  20. Long-term Follow-up of Acute Isolated Accommodation Insufficiency

    PubMed Central

    Lee, Jung Jin; Baek, Seung-Hee

    2013-01-01

    Purpose To define the long-term results of accommodation insufficiency and to investigate the correlation between accommodation insufficiency and other factors including near point of convergence (NPC), age, and refractive errors. Methods From January 2008 to December 2009, 11 patients with acute near vision disturbance and remote near point of accommodation (NPA) were evaluated. Full ophthalmologic examinations, including best corrected visual acuity, manifest refraction and prism cover tests were performed. Accommodation ability was measured by NPA using the push-up method. We compared accommodation insufficiency and factors including age, refractive errors and NPC. We also investigated the recovery from loss of accommodation in patients. Results Mean age of patients was 20 years (range, 9 to 34 years). Five of the 11 patients were female. Mean refractive error was -0.6 diopters (range, -3.5 to +0.25 diopters) and 8 of 11 patients (73%) had emmetropia (+0.50 to -0.50 diopters). No abnormalities were found in brain imaging tests. Refractive errors were not correlated with NPA or NPC (rho = 0.148, p = 0.511; rho = 0.319, p = 0.339; respectively). The correlation between age and NPA was not significant (rho = -395, p = 0.069). However, the correlation between age and NPC was negative (rho = -0.508, p = 0.016). Three of 11 patients were lost to follow-up, and 6 of 8 patients had permanent insufficiency of accommodation. Conclusions Accommodation insufficiency is most common in emmetropia, however, refractive errors and age are not correlated with accommodation insufficiency. Dysfunction of accommodation can be permanent in the isolated accommodation insufficiency. PMID:23543051

  1. Accommodation training in foreign workers.

    PubMed

    Takada, Masumi; Miyao, Masaru; Matsuura, Yasuyuki; Takada, Hiroki

    2013-01-01

    By relaxing the contracted focus-adjustment muscles around the eyeball, known as the ciliary and extraocular muscles, the degree of pseudomyopia can be reduced. This understanding has led to accommodation training in which a visual target is presented in stereoscopic video clips. However, it has been pointed out that motion sickness can be induced by viewing stereoscopic video clips. In Measurement 1 of the present study, we verified whether the new 3D technology reduced the severity of motion sickness in accordance with stabilometry. We then evaluated the short-term effects of accommodation training using new stereoscopic video clips on foreign workers (11 females) suffering from eye fatigue in Measurement 2. The foreign workers were trained for three days. As a result, visual acuity was statistically improved by continuous accommodation training, which will help promote ciliary muscle stretching.

  2. 38 CFR 18.412 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... known physical or mental limitations of a handicapped applicant or employee if such accommodation would... that the accommodation would impose an undue hardship on the operation of its program or activity. (b... impose an undue hardship on the operation of a recipient's program or activity, factors to be considered...

  3. Accommodation Outcomes and the ICF Framework

    ERIC Educational Resources Information Center

    Schreuer, Naomi

    2009-01-01

    Accommodation of the environment and technology is one of the key mediators of adjustment to disability and participation in community. In this article, accommodations are tested empirically as facilitators of return to work and participation, as defined by the "International Classification of Disability, Function, and Health" (ICF) and…

  4. Beyond Psychometric Evaluation of the Student--Task Determinants of Accommodation: Why Students with Learning Disabilities May Not Need to Be Accommodated

    ERIC Educational Resources Information Center

    Roberts, Barbara L.

    2012-01-01

    Students with learning disabilities obtain a wide range of recommended accommodations in secondary school, which they anticipate will continue into postsecondary education. Although the student's specific learning disability (SLD) contributes to the accommodation planning process, it is not the sole determinant of appropriate accommodation.…

  5. Job Accommodation System: Project TIE (Technology in Employment).

    ERIC Educational Resources Information Center

    Roberts, Gary; Zimbrich, Karen; Butterworth, John; Hart, Debra

    This manual presents a comprehensive evaluation tool that can be used by employees with disabilities, by rehabilitation practitioners, and by consultants to develop job accommodations in a variety of employment settings. The Job Accommodation System is designed to help in identifying, selecting, and implementing job accommodations and consists of…

  6. Accommodations Manual: How to Select, Administer, and Evaluate Use of Accommodations for Instruction and Assessment of Students with Disabilities. Third Edition

    ERIC Educational Resources Information Center

    Christensen, L.; Carver, W.; VanDeZande, J.; Lazarus, S.

    2011-01-01

    The Council of Chief State School Officers' "Accommodations Manual: How to Select, Administer, and Evaluate the Use of Accommodations for Instruction and Assessment of Students with Disabilities" was first developed to establish guidelines for states to use for the selection, administration, and evaluation of accommodations for…

  7. Lenticular accommodation in relation to ametropia: the chick model.

    PubMed

    Choh, Vivian; Sivak, Jacob G

    2005-03-04

    Our goal was to determine whether experimentally induced ametropias have an effect on lenticular accommodation and spherical aberration. Form-deprivation myopia and hyperopia were induced in one eye of hatchling chicks by application of a translucent goggle and +15 D lens, respectively. After 7 days, eyes were enucleated and lenses were optically scanned prior to accommodation, during accommodation, and after accommodation. Accommodation was induced by electrical stimulation of the ciliary nerve. Lenticular focal lengths for form-deprived eyes were significantly shorter than for their controls and accommodation-associated changes in focal length were significantly smaller in myopic eyes compared to their controls. For eyes imposed with +15 D blur, focal lengths were longer than those for their controls and accommodative changes were greater. Spherical aberration of the lens increased with accommodation in both form-deprived and lens-treated birds, but induction of ametropia had no effect on lenticular spherical aberration in general. Nonmonotonicity from lenticular spherical aberration increased during accommodation but effects of refractive error were equivocal. The crystalline lens contributes to refractive error changes of the eye both in the case of myopia and hyperopia. These changes are likely attributable to global changes in the size and shape of the eye.

  8. Transitions: Times of Change and Accommodation.

    ERIC Educational Resources Information Center

    Rice, Mabel L.; O'Brien, Marion

    1990-01-01

    The research literature is reviewed for transitions from birth to eight years. A model describes transition as a change in ecocultural niche, requiring accommodations in daily routines for a child, family, and service providers and transition impact measures the number of accommodations required and the sustainability of daily routines.…

  9. Phacoemulsification and implantation of an accommodating IOL after PRK.

    PubMed

    Aslanides, loannis M; Plainis, Sotiris; Kumar, Vinod; Ginis, Harilaos

    2006-01-01

    To present a case of phacoemulsification and implantation of an accommodating intraocular lens (IOL) in a patient with cataract formation after previous refractive surgery. A 50-year-old man, who initially had photorefractive keratectomy to correct moderate myopia, developed a cataract in one eye. He subsequently underwent phacoemulsification and implantation of a 1CU accommodating IOL, as he wished to remain spectacle independent. The patient's distance vision was fully restored. However, accommodative function, which was assessed using subjective and novice objective techniques, was only partially restored. Although the accommodating IOL fully restored the patient's distance vision, accommodative function was only partially restored.

  10. Framing Appropriate Accommodations in Terms of Individual Need: Examining the Fit of Four Approaches to Selecting Test Accommodations of English Language Learners

    ERIC Educational Resources Information Center

    Koran, Jennifer; Kopriva, Rebecca J.

    2017-01-01

    Providing appropriate test accommodations to most English language learners (ELLs) is important to facilitate meaningful inferences about learning. This study compared teacher large-scale test accommodation recommendations to those from a literature- and practitioner-grounded accommodation selection taxonomy. The taxonomy links student-specific…

  11. Bearing-Mounting Concept Accommodates Thermal Expansion

    NASA Technical Reports Server (NTRS)

    Nespodzany, Robert; Davis, Toren S.

    1995-01-01

    Pins or splines allow radial expansion without slippage. Design concept for mounting rotary bearing accommodates differential thermal expansion between bearing and any structure(s) to which bearing connected. Prevents buildup of thermal stresses by allowing thermal expansion to occur freely but accommodating expansion in such way not to introduce looseness. Pin-in-slot configuration also maintains concentricity.

  12. Corneal changes with accommodation using dual Scheimpflug photography.

    PubMed

    Sisó-Fuertes, Irene; Domínguez-Vicent, Alberto; del Águila-Carrasco, Antonio; Ferrer-Blasco, Teresa; Montés-Micó, Robert

    2015-05-01

    To assess whether corneal parameters and aberrations are affected by accommodation. Optics Department, University of Valencia, Valencia, Spain. Prospective cross-sectional study. The Galilei G4 dual Scheimpflug device was used to obtain data on the anterior and posterior axial curvatures, total corneal power (TCP), and corneal pachymetry from 3 corneal zones (central: 0.0 up to 4.0 mm; paracentral or mid: 4.0 up to 7.0 mm; peripheral: 7.0 up to 10.0 mm) in young emmetropic eyes in the unaccommodated and 4 accommodated states (from -1.0 to -4.0 diopters [D] in 1.0 D steps). The 2nd-, 3rd-, and 4th-order aberrations as well as the root mean square (RMS) were also determined for the entire cornea at the same accommodative demands. The study evaluated 7 subjects (12 eyes). No significant changes in any measured parameter were found during accommodation for any corneal zone (P > .05). Statistically significant differences were found in the various corneal zones when it was assumed they were constant with accommodation (P < .01). A stable linear trend with accommodation was also found for corneal aberrations, although individual variations existed because of the high standard deviation values. Different parameters in various zones of the cornea as well as corneal aberrations were stable during accommodation. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

  13. What Works? Toward a New Classification System for Mental Health Supported Accommodation Services: The Simple Taxonomy for Supported Accommodation (STAX-SA)

    PubMed Central

    McPherson, Peter; Krotofil, Joanna

    2018-01-01

    Inconsistent terminology and variation in service models have made synthesis of the supported accommodation literature challenging. To overcome this, we developed a brief, categorical taxonomy that aimed to capture the defining features of different supported accommodation models: the simple taxonomy for supported accommodation (STAX-SA). Data from a previous review of existing classification systems were used to develop the taxonomy structure. After initial testing and amendments, the STAX-SA and an existing taxonomy were applied to 132 supported accommodation service descriptions drawn from two systematic reviews and their performance compared. To assess external validity, the STAX-SA was distributed to a sample of supported accommodation managers in England and they were asked to use it to classify their services. The final version of the STAX-SA comprised of five supported accommodation ‘types’, based on four domains; Staffing location; Level of support; Emphasis on move-on; and Physical setting. The STAX-SA accurately categorized 71.1% (n = 94) of service descriptions, outperforming the comparison tool, and was not affected by publication date or research design. The STAX-SA effectively discriminated between ‘real world’ service models in England and 53.2% (n = 17) of service managers indicated that the taxonomy was ‘Very effective’ or ‘Extremely effective’ in capturing key characteristics of their service. The STAX-SA is an effective tool for classifying supported accommodation models and represents a promising approach to synthesizing the extant effectiveness literature. The authors recommend the development of reporting guidelines for future supported accommodation publications to facilitate comparison between models. PMID:29364171

  14. What Works? Toward a New Classification System for Mental Health Supported Accommodation Services: The Simple Taxonomy for Supported Accommodation (STAX-SA).

    PubMed

    McPherson, Peter; Krotofil, Joanna; Killaspy, Helen

    2018-01-24

    Inconsistent terminology and variation in service models have made synthesis of the supported accommodation literature challenging. To overcome this, we developed a brief, categorical taxonomy that aimed to capture the defining features of different supported accommodation models: the simple taxonomy for supported accommodation (STAX-SA). Data from a previous review of existing classification systems were used to develop the taxonomy structure. After initial testing and amendments, the STAX-SA and an existing taxonomy were applied to 132 supported accommodation service descriptions drawn from two systematic reviews and their performance compared. To assess external validity, the STAX-SA was distributed to a sample of supported accommodation managers in England and they were asked to use it to classify their services. The final version of the STAX-SA comprised of five supported accommodation 'types', based on four domains; Staffing location ; Level of support ; Emphasis on move-on ; and Physical setting . The STAX-SA accurately categorized 71.1% ( n = 94) of service descriptions, outperforming the comparison tool, and was not affected by publication date or research design. The STAX-SA effectively discriminated between 'real world' service models in England and 53.2% ( n = 17) of service managers indicated that the taxonomy was ' Very effective ' or ' Extremely effective ' in capturing key characteristics of their service. The STAX-SA is an effective tool for classifying supported accommodation models and represents a promising approach to synthesizing the extant effectiveness literature. The authors recommend the development of reporting guidelines for future supported accommodation publications to facilitate comparison between models.

  15. Reserving Interior Void Space for Volume Change Accommodation: An Example of Cable-Like MWNTs@SnO2@C Composite for Superior Lithium and Sodium Storage.

    PubMed

    Zhao, Yi; Wei, Chao; Sun, Shengnan; Wang, Luyuan Paul; Xu, Zhichuan J

    2015-06-01

    Reserving interior void space in the cable-like structure of multiwalled carbon nanotubes-in-SnO 2 -in-carbon layer (MWNTs@SnO 2 @C) is reported for the first time. Such a design enables the structure performing excellent for Li and Na storage, which benefit from the good electrical conductivity of MWNTs and carbon layer as well as the reserved void space to accommodate the volume changes of SnO 2 .

  16. Functional spasm of accommodation: Changes on scheimpflug imaging

    PubMed Central

    Sukhija, Jaspreet; Dogra, Mangat R.; Zadeng, Thara; Ram, Jagat

    2014-01-01

    Spasm of accommodation is a rare condition characterized by a sudden increase in myopia. It can occur in emmetropes, hypermetropes and myopes. All the physiological changes that occur in normal accommodation are exaggerated. Mostly the cause is functional disorder and the condition gradually improves. We hereby present the changes occurring in spasm of accommodation as seen on Scheimpflug imaging. PMID:25378883

  17. Age-Related Changes in Accommodative Dynamics from Preschool to Adulthood

    PubMed Central

    Glasser, Adrian; Manny, Ruth E.; Stuebing, Karla K.

    2010-01-01

    Purpose. To study variations in dynamic measures of accommodation and disaccommodation with age in subjects ranging from preschool to adulthood. Methods. Accommodative responses to a step stimulus cartoon movie alternating from distance to near were recorded with a dynamic infrared photorefractor. Subjects viewed at least three stimulus cycles of far and near for four near stimulus demands (2, 3, 4, and 5 D). Latencies, peak velocities, and the magnitude of accommodative microfluctuations were calculated from the responses and compared in 41 subjects from 3 to 38 years of age. Results. Mean accommodative and disaccommodative latencies decreased linearly with age. The magnitude of accommodative microfluctuations during sustained near accommodation had a significant quadratic relationship to age, with subjects in the first decade of life having the largest fluctuations and subjects in the third decade of life having the smallest for all stimulus demands. Accommodative peak velocities were fastest in subjects in the first two decades of life, compared with subjects in the third and fourth decades; however, disaccommodative peak velocities showed no significant age differences. Conclusions. Age-related changes in dynamics occur in accommodative and disaccommodative latencies, accommodative peak velocities, and accommodative microfluctuations, all of which decrease with increasing age from preschool to adulthood. Disaccommodative peak velocities showed no change with age. PMID:19684002

  18. Communication Accommodation between Chinese and Australian Students and Academic Staff.

    ERIC Educational Resources Information Center

    Gallois, Cynthia; And Others

    A study tested paths predicted by Communication Accommodation Theory (CAT) in the context of interactions between 105 Chinese and 283 Anglo-Australian students and 98 academic staff in situations of potential conflict. Videotapes of student-lecturer interactions in which speakers accommodated, over-accommodated, or under-accommodated were rated by…

  19. 28 CFR 36.310 - Transportation provided by public accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Transportation provided by public... BASIS OF DISABILITY BY PUBLIC ACCOMMODATIONS AND IN COMMERCIAL FACILITIES Specific Requirements § 36.310 Transportation provided by public accommodations. (a) General. (1) A public accommodation that provides...

  20. [Monochromatic aberration in accommodation. Dynamic wavefront analysis].

    PubMed

    Fritzsch, M; Dawczynski, J; Jurkutat, S; Vollandt, R; Strobel, J

    2011-06-01

    Monochromatic aberrations may influence the visual acuity of the eye. They are not stable and can be affected by different factors. The subject of the following paper is the dynamic investigation of the changes in wavefront aberration with accommodation. Dynamic measurement of higher and lower order aberrations was performed with a WASCA Wavefront Analyzer (Carl-Zeiss-Meditec) and a specially constructed target device for aligning objects in far and near distances on 25 subjects aged from 15 to 27 years old. Wavefront aberrations showed some significant changes in accommodation. In addition to the characteristic sphere reaction accompanying miosis and changes in horizontal prism (Z(1) (1)) in the sense of a convergence movement of the eyeball also occurred. Furthermore defocus rose (Z(2) (0)) and astigmatism (Z(2) (-2)) changed. In higher-order aberrations a decrease in coma-like Zernike polynomials (Z(3) (-1), Z(3) (1)) was found. The most obvious change appeared in spherical aberration (Z(4) (0)) which increased and changed from positive to negative. In addition the secondary astigmatism (Z(4) (-2)) and quadrafoil (Z(4) (4)) rise also increased. The total root mean square (RMS), as well as the higher-order aberrations (RMS-HO) significantly increased in accommodation which is associated with a theoretical reduction of visual acuity. An analysis of the influence of pupil size on aberrations showed significant increases in defocus, spherical aberration, quadrafoil, RMS and RMS HO by increasing pupil diameter. By accommodation-associated miosis, the growing aberrations are partially compensated by focusing on near objects. Temporal analysis of the accommodation process with dynamic wavefront analysis revealed significant delays in pupil response and changing of prism in relation to the sphere reaction. In accommodation to near objects a discrete time ahead of third order aberrations in relation to the sphere response was found. Using dynamic wavefront measurement

  1. Operationalizing workplace accommodations for individuals with disabilities: A scoping review.

    PubMed

    Sundar, Vidya

    2017-01-01

    The provision of workplace accommodations is a proven strategy in supporting individuals with disabilities at work. Accommodations include a wide range of supports and strategies that are not very well defined beyond the Americans with Disabilities Act in the United States. Understanding the landscape of accommodations is important to measure the impact of programs that support employment of individuals with disabilities. To conduct a scoping review and thematic analysis of research literature to identify how workplace accommodations are operationalized and to identify knowledge gaps in its conceptualization. Keywords searches were conducted in seven electronic databases. Title, abstract, and full text screening was conducted followed by a thematic analysis of the content to identify how workplace accommodations are operationalized. Overall, 47 studies were selected for review. 433 different types of accommodations were identified, of which assistive technology and specialized equipment represented the most frequently reported type of accommodation (40%). A very small percentage of studies included policy changes (9%) and human assistance (5%) as an accommodation strategy. This scoping review aims to clarify how accommodations are operationalized in the research literature. Key knowledge gaps identified include the systematic exclusion of certain types of supports or disability types.

  2. Anthropometric Accommodation in Space Suit Design

    NASA Technical Reports Server (NTRS)

    Rajulu, Sudhakar; Thaxton, Sherry

    2007-01-01

    Design requirements for next generation hardware are in process at NASA. Anthropometry requirements are given in terms of minimum and maximum sizes for critical dimensions that hardware must accommodate. These dimensions drive vehicle design and suit design, and implicitly have an effect on crew selection and participation. At this stage in the process, stakeholders such as cockpit and suit designers were asked to provide lists of dimensions that will be critical for their design. In addition, they were asked to provide technically feasible minimum and maximum ranges for these dimensions. Using an adjusted 1988 Anthropometric Survey of U.S. Army (ANSUR) database to represent a future astronaut population, the accommodation ranges provided by the suit critical dimensions were calculated. This project involved participation from the Anthropometry and Biomechanics facility (ABF) as well as suit designers, with suit designers providing expertise about feasible hardware dimensions and the ABF providing accommodation analysis. The initial analysis provided the suit design team with the accommodation levels associated with the critical dimensions provided early in the study. Additional outcomes will include a comparison of principal components analysis as an alternate method for anthropometric analysis.

  3. Maximum human objectively measured pharmacologically stimulated accommodative amplitude.

    PubMed

    Grzybowski, Andrzej; Schachar, Ronald A; Gaca-Wysocka, Magdalena; Schachar, Ira H; Pierscionek, Barbara K

    2018-01-01

    To measure the maximum, objectively measured, accommodative amplitude, produced by pharmacologic stimulation. Thirty-seven healthy subjects were enrolled, with a mean age of 20.2±1.1 years, corrected visual acuity of 20/20, and mean spherical equivalent refraction (SER) =-0.83±1.60 diopters. For each subject, the right pupil was dilated with phenylephrine 10%. After 30 minutes, the pupil was measured, the left eye was patched, and the right eye was autorefracted. Pilocarpine 4% was then instilled in the right eye, followed by phenylephrine. At 45 minutes after the pilocarpine, autorefraction and pupil size were again measured. Mean pupil size pre- and postpilocarpine was 8.0±0.8 mm and 4.4±1.9 mm, respectively. Pre- and postpilocarpine, the mean SER was -0.83±1.60 and -10.55±4.26 diopters, respectively. The mean pilocarpine-induced accommodative amplitude was 9.73±3.64 diopters. Five subjects had accommodative amplitudes ≥14.00 diopters. Accommodative amplitude was not significantly related to baseline SER ( p -value =0.24), pre- or postpilocarpine pupil size ( p -values =0.13 and 0.74), or change in pupil size ( p -value =0.37). Iris color did not statistically significantly affect accommodative amplitude ( p -value =0.83). Following topically applied pilocarpine, the induced objectively measured accommodation in the young eye is greater than or equal to the reported subjectively measured voluntary maximum accommodative amplitude.

  4. Restoration of accommodation: surgical options for correction of presbyopia

    PubMed Central

    Glasser, Adrian

    2010-01-01

    Accommodation is a dioptric change in the power of the eye to see clearly at near. Ciliary muscle contraction causes a release in zonular tension at the lens equator, which permits the elastic capsule to mould the young lens into an accommodated form. Presbyopia, the gradual age-related loss of accommodation, occurs primarily through a gradual age-related stiffening of the lens. While there are many possible options for relieving the symptoms of presbyopia, only relatively recently has consideration been given to surgical restoration of accommodation to the presbyopic eye. To understand how this might be achieved, it is necessary to understand the accommodative anatomy, the mechanism of accommodation and the causes of presbyopia. A variety of different kinds of surgical procedures has been considered for restoring accommodation to the presbyopic eye, including surgical expansion of the sclera, using femtosecond lasers to treat the lens or with so-called accommodative intraocular lenses (IOLs). Evidence suggests that scleral expansion cannot and does not restore accommodation. Laser treatments of the lens are in their early infancy. Development and testing of accommodative IOLs are proliferating. They are designed to produce a myopic refractive change in the eye in response to ciliary muscle contraction either through a movement of an optic or through a change in surface curvature. Three general design principles are being considered. These are single optic IOLs that rely on a forward shift of the optic, dual optic IOLs that rely on an increased separation between the two optics, or IOLs that permit a change in surface curvature to produce an increase in optical power in response to ciliary muscle contraction. Several of these different IOLs are available and being used clinically, while many are still in research and development. PMID:18399800

  5. Dynamic accommodation with simulated targets blurred with high order aberrations

    PubMed Central

    Gambra, Enrique; Wang, Yinan; Yuan, Jing; Kruger, Philip B.; Marcos, Susana

    2010-01-01

    High order aberrations have been suggested to play a role in determining the direction of accommodation. We have explored the effect of retinal blur induced by high order aberrations on dynamic accommodation by measuring the accommodative response to sinusoidal variations in accommodative demand (1–3 D). The targets were blurred with 0.3 and 1 μm (for a 3-mm pupil) of defocus, coma, trefoil and spherical aberration. Accommodative gain decreased significantly when 1-μm of aberration was induced. We found a strong correlation between the relative accommodative gain (and phase lag) and the contrast degradation imposed on the target at relevant spatial frequencies. PMID:20600230

  6. Objective measurement of accommodative biometric changes using ultrasound biomicroscopy

    PubMed Central

    Ramasubramanian, Viswanathan; Glasser, Adrian

    2015-01-01

    PURPOSE To demonstrate that ultrasound biomicroscopy (UBM) can be used for objective quantitative measurements of anterior segment accommodative changes. SETTING College of Optometry, University of Houston, Houston, Texas, USA. DESIGN Prospective cross-sectional study. METHODS Anterior segment biometric changes in response to 0 to 6.0 diopters (D) of accommodative stimuli in 1.0 D steps were measured in eyes of human subjects aged 21 to 36 years. Imaging was performed in the left eye using a 35 MHz UBM (Vumax) and an A-scan ultrasound (A-5500) while the right eye viewed the accommodative stimuli. An automated Matlab image-analysis program was developed to measure the biometry parameters from the UBM images. RESULTS The UBM-measured accommodative changes in anterior chamber depth (ACD), lens thickness, anterior lens radius of curvature, posterior lens radius of curvature, and anterior segment length were statistically significantly (P < .0001) linearly correlated with accommodative stimulus amplitudes. Standard deviations of the UBM-measured parameters were independent of the accommodative stimulus demands (ACD 0.0176 mm, lens thickness 0.0294 mm, anterior lens radius of curvature 0.3350 mm, posterior lens radius of curvature 0.1580 mm, and anterior segment length 0.0340 mm). The mean difference between the A-scan and UBM measurements was −0.070 mm for ACD and 0.166 mm for lens thickness. CONCLUSIONS Accommodating phakic eyes imaged using UBM allowed visualization of the accommodative response, and automated image analysis of the UBM images allowed reliable, objective, quantitative measurements of the accommodative intraocular biometric changes. PMID:25804579

  7. Assessment of launch site accommodations versus Spacelab payload requirements

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The Kennedy launch site capability for accommodating spacelab payload operations was assessed. Anomalies between facility accommodations and requirements for the Spacelab III (Strawman), OA Mission 83-2, Dedicated Life Sciences, and Combined Astronomy missions are noted. Recommendations for revision of the accommodations handbook are summarized.

  8. Computer-animated model of accommodation and presbyopia.

    PubMed

    Goldberg, Daniel B

    2015-02-01

    To understand, demonstrate, and further research the mechanisms of accommodation and presbyopia. Private practice, Little Silver, New Jersey, USA. Experimental study. The CAMA 2.0 computer-animated model of accommodation and presbyopia was produced in collaboration with an experienced medical animator using Autodesk Maya animation software and Adobe After Effects. The computer-animated model demonstrates the configuration and synchronous movements of all accommodative elements. A new classification of the zonular apparatus based on structure and function is proposed. There are 3 divisions of zonular fibers; that is, anterior, crossing, and posterior. The crossing zonular fibers form a scaffolding to support the lens; the anterior and posterior zonular fibers work reciprocally to achieve focused vision. The model demonstrates the important support function of Weiger ligament. Dynamic movement of the ora serrata demonstrates that the forces of ciliary muscle contraction store energy for disaccommodation in the elastic choroid. The flow of aqueous and vitreous provides strong evidence for our understanding of the hydrodynamic interactions during the accommodative cycle. The interaction may result from the elastic stretch in the choroid transmitted to the vitreous rather than from vitreous pressue. The model supports the concept that presbyopia results from loss of elasticity and increasing ocular rigidity in both the lenticular and extralenticular structures. The computer-animated model demonstrates the structures of accommodation moving in synchrony and might enhance understanding of the mechanisms of accommodation and presbyopia. Dr. Goldberg is a consultant to Acevision, Inc., and Bausch & Lomb. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  9. Ocular Aberrations Across the Visual Field During Accommodation

    NASA Astrophysics Data System (ADS)

    Liu, Tao

    Myopia is classically defined as a mismatch between the optical power of the relaxed eye and its dioptric length. This definition is entirely foveocentric without concern for the contributions of peripheral refractive errors to myopia development. Long periods of steady near-work was considered to cause myopia development due to inadequate accommodation. Consequently, not only the on-axis optical features but also off-axis ones should be probed to gain insight about myopia progression. Moreover, these features need to be understood not only for the relaxed eye, but also for the accommodating eye. To acquire complete data set, a custom-built Indiana Scanning Aberrometer for Wavefront (I SAW) was developed to measure wavefront aberration along 37 line-of-sights at 8 different accommodation states in the central 30 degree visual field. We found that ocular refractive state changed uniformly over the central visual field as the eye accommodates up to 6D, and the accuracy of accommodation across the central visual field is similar to that measured in the fovea. No systematic difference between emmetropic and myopic eyes was evident. Then, a linear vector-summation rule for axial and oblique astigmatism was found to account for their interaction over the central visual field. Using this combination rule, our experimental evidence revealed no systematic effect of accommodation on axial or oblique astigmatism for two adult populations. The axial and oblique astigmatism of the whole eye is less than for the cornea alone, indicating a compensatory role for internal optics at all accommodative states. This compensation mechanism was further validated theoretically with schematic eye model. Lastly, we developed a hybrid method yielding customized eye models that accurately reproduce the empirical measurements and reasonably represent the anatomical structure, thus providing a mechanistic explanation for the changes in the eye's aberration structure that occur over the central

  10. An Analysis and Rejection of Arguments for Religious Accommodation

    ERIC Educational Resources Information Center

    Kline, Lisa Anne

    2009-01-01

    This dissertation provides a comprehensive critical analysis of six main arguments for religious accommodation, with a specific focus on fundamentalist religious groups and the accommodation of their practices within liberal democratic societies. This analysis reveals that the types of practices that these arguments aim to accommodate primarily…

  11. Long-term reproducibility of Edinger-Westphal stimulated accommodation in rhesus monkeys.

    PubMed

    He, Lin; Wendt, Mark; Glasser, Adrian

    2013-08-01

    If longitudinal studies of accommodation or accommodation restoration procedures are undertaken in rhesus monkeys, the methods used to induce and measure accommodation must remain reproducible over the study period. Stimulation of the Edinger-Westphal (EW) nucleus in anesthetized rhesus monkeys is a valuable method to understand various aspects of accommodation. A prior study showed reproducibility of EW-stimulated accommodation over 14 months after chronic electrode implantation. However, reproducibility over a period longer than this has not been investigated and therefore remains unknown. To address this, accommodation stimulation experiments in four eyes of two rhesus monkeys (13.7 and 13.8 years old) were evaluated over a period of 68 months. Carbachol iontophoresis stimulated accommodation was first measured with a Hartinger coincidence refractometer (HCR) two weeks before electrode implantation to determine maximum accommodative amplitudes. EW stimulus-response curves were initially measured with the HCR one month after electrode implantation and then repeated at least six times for each eye in the following 60 months. At 64 months, carbachol iontophoresis induced accommodation was measured again. At 68 months, EW stimulus-response curves were measured with an HCR and photorefraction every week over four consecutive weeks to evaluate the short-term reproducibility over one month. In the four eyes studied, long-term EW-stimulated accommodation decreased by 7.00 D, 3.33 D, 4.63 D, and 2.03 D, whereas carbachol stimulated accommodation increased by 0.18 D-0.49 D over the same time period. The short-term reproducibility of maximum EW-stimulated accommodation (standard deviations) over a period of four weeks at 68 months after electrode implantation was 0.48 D, 0.79 D, 0.55 D and 0.39 D in the four eyes. Since the long-term decrease in EW-stimulated accommodation is not matched by similar decreases in carbachol iontophoresis stimulated accommodation, the decline

  12. Carbon Nanotubes: On the Origin of Helicity

    NASA Astrophysics Data System (ADS)

    Harutyunyan, Avetik

    2015-03-01

    The mechanism of helicity formation of carbon nanotubes still remains elusive that hinders their applications. Current explanations mainly rely on the planar interrelationship between the structure of nanotube and corresponding facet of catalyst in 2D geometry that could amend the structure of grown carbon layer, specifically due to the epitaxial interaction. Yet, the structure of carbon nanotube and circumference of the rims assume involvement of more than one facet i.e. it is 3D problem. By aiming this problem we find that the nanotube nucleation is initiated by cap formation via evolving of graphene embryo across the adjacent facets of catalyst particle. As a result the graphene embryos incorporate in their hexagonic network various polygons to accommodate the curved 3D geometry that initiates cap formation following by elongation of the circumferential rims. Based on these results, also on the census of nanotube caps and the fact that given cap fit only one nanotube wall, we consider carbon cap responsible for the helicity of carbon nanotube. This understanding could provide new avenues towards engineering particles to explicitly accommodate certain helicities via exploitation of the angular distribution of catalyst adjacent facets. Our recent progresses in production of carbon nanotubes, nanotube reinforced composites and their potential applications also will be presented.

  13. Accommodations: Assisting Students with Disabilities. Third Edition

    ERIC Educational Resources Information Center

    Beech, Marty

    2010-01-01

    This document updates "Accommodations: Assisting Students with Disabilities. A Guide for Educators," published by the Florida Department of Education (FDOE) in 2003. This document is written to assist school district personnel and parents when making decisions about the use of accommodations by students with disabilities in instructional…

  14. 14 CFR § 1251.201 - Reasonable accommodation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ON BASIS OF HANDICAP Employment Practices § 1251.201 Reasonable accommodation. (a) A recipient shall... handicapped applicant or employee unless the recipient can demonstrate that the accommodation would impose an...) Making facilities used by employees readily accessible to and usable by handicapped persons; and (2) Job...

  15. 7 CFR 15b.13 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...) A recipient shall make reasonable accommodation to the known physical or mental limitations of an... accommodation would impose an undue hardship on the operation of its program or activity. (b) Reasonable... undue hardship on the operation of a recipient's programs or activities, factors to be considered...

  16. Recommendations for Accommodations: Implications of (In)consistency

    ERIC Educational Resources Information Center

    Ketterlin-Geller, Leanne R.

    2007-01-01

    When accurately assigned and administered appropriately, testing accommodations help ameliorate the effects of personal characteristics that limit access to critical information and prevent a person from demonstrating his or her true abilities in the tested domain. Inaccurate assignment or misuse of accommodations may counteract the benefits of…

  17. 46 CFR 154.325 - Accommodation, service, and control spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Accommodation, service, and control spaces. 154.325... Equipment Ship Arrangements § 154.325 Accommodation, service, and control spaces. (a) Accommodation, service, and control spaces must be outside the cargo area. (b) If a hold space having a cargo containment...

  18. 46 CFR 154.325 - Accommodation, service, and control spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Accommodation, service, and control spaces. 154.325... Equipment Ship Arrangements § 154.325 Accommodation, service, and control spaces. (a) Accommodation, service, and control spaces must be outside the cargo area. (b) If a hold space having a cargo containment...

  19. 46 CFR 154.325 - Accommodation, service, and control spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Accommodation, service, and control spaces. 154.325... Equipment Ship Arrangements § 154.325 Accommodation, service, and control spaces. (a) Accommodation, service, and control spaces must be outside the cargo area. (b) If a hold space having a cargo containment...

  20. Effects of visual imagery on the accommodation response

    NASA Technical Reports Server (NTRS)

    Malmstrom, F. V.; Randle, R. J.

    1976-01-01

    Twenty-seven naive male subjects were tested to determine whether they could effect appropriate accommodation changes in an empty field by 'thinking near' and 'thinking far'. Evidence indicated that naive subjects could effect significant and appropriate accommodation changes, but only about a steady-state value of 1.0 diopter. Additionally, the data support the hypothesis that the resting state of accommodation is not at the visual far point, but, rather, at about 1.0 diopter.

  1. Workplace accommodations for people with mental illness: a scoping review.

    PubMed

    McDowell, Caitlin; Fossey, Ellie

    2015-03-01

    Disability discrimination legislation means that employees with a disability or mental illness are legally entitled to reasonable workplace accommodations that enable them to work effectively and safely. This scoping review aims to investigate the types of workplace accommodations provided for people with mental illness, and their costs and benefits. A literature search was conducted using five electronic databases. Peer reviewed research articles published between 1993 and June 2013 were included in this scoping review and their quality was assessed. Opinion papers, reports, and case descriptions were excluded. Nine studies explored workplace accommodations for people with mental illness. The most commonly reported work-related accommodations were flexible scheduling/reduced hours, modified training and supervision, and modified job duties/descriptions. The least common type of accommodation was physical modification to the workplace. For employees with persistent mental illness who were accessing a supported employment agency, the majority of accommodations related to support from the job coach or employment specialist, such as facilitating communication with the employer during hiring or on the job. The quality of the studies varied considerably and the benefits of the accommodations are not yet well documented. There is limited evidence that a larger number of workplace accommodations are associated with longer job tenure. Workplace accommodations appear to be important to support employees with mental illness, but more accessible information about how disability discrimination legislation applies to this population is needed. Future research should address the implementation and effectiveness of mental health-related workplace accommodations.

  2. Vergence driven accommodation with simulated disparity in myopia and emmetropia.

    PubMed

    Maiello, Guido; Kerber, Kristen L; Thorn, Frank; Bex, Peter J; Vera-Diaz, Fuensanta A

    2018-01-01

    The formation of focused and corresponding foveal images requires a close synergy between the accommodation and vergence systems. This linkage is usually decoupled in virtual reality systems and may be dysfunctional in people who are at risk of developing myopia. We study how refractive error affects vergence-accommodation interactions in stereoscopic displays. Vergence and accommodative responses were measured in 21 young healthy adults (n=9 myopes, 22-31 years) while subjects viewed naturalistic stimuli on a 3D display. In Step 1, vergence was driven behind the monitor using a blurred, non-accommodative, uncrossed disparity target. In Step 2, vergence and accommodation were driven back to the monitor plane using naturalistic images that contained structured depth and focus information from size, blur and/or disparity. In Step 1, both refractive groups converged towards the stereoscopic target depth plane, but the vergence-driven accommodative change was smaller in emmetropes than in myopes (F 1,19 =5.13, p=0.036). In Step 2, there was little effect of peripheral depth cues on accommodation or vergence in either refractive group. However, vergence responses were significantly slower (F 1,19 =4.55, p=0.046) and accommodation variability was higher (F 1,19 =12.9, p=0.0019) in myopes. Vergence and accommodation responses are disrupted in virtual reality displays in both refractive groups. Accommodation responses are less stable in myopes, perhaps due to a lower sensitivity to dioptric blur. Such inaccuracies of accommodation may cause long-term blur on the retina, which has been associated with a failure of emmetropization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Extended Time Testing Accommodations: What Does the Research Say?

    ERIC Educational Resources Information Center

    Lovett, Benjamin J.

    2011-01-01

    Extended time is among the most common testing accommodations given to students with a wide range of disabilities. However, although school psychologists are often involved in accommodation decisions, many are unaware of research from the past decade that has changed their understanding of extended time. Used properly, testing accommodations let…

  4. Normal and Tangential Momentum Accommodation for Earth Satellite Conditions

    NASA Technical Reports Server (NTRS)

    Knechtel, Earl D.; Pitts, William C.

    1973-01-01

    Momentum accommodation was determined experimentally for gas-surface interactions simulating in a practical way those of near-earth satellites. Throughout the ranges of gas energies and incidence angles of interest for earth-conditions, two components of force were measured by means of a vacuum microbalance to determine the normal and tangential momentum-accommodation coefficients for nitrogen ions on technical-quality aluminum surfaces. For these experimental conditions, the electrodynamics of ion neutralization near the surface indicate that results for nitrogen ions should differ relatively little from those for nitrogen molecules, which comprise the largest component of momentum flux for near-earth satellites. The experimental results indicated that both normal and tangential momentum-accommodation coefficients varied widely with energy, tending to be relatively well accommodated at the higher energies, but becoming progressively less accommodated as the energy was reduced to and below that for earth-satellite speeds. Both coefficients also varied greatly with incidence angle, the normal momentum becoming less accommodated as the incidence angle became more glancing, whereas the tangential momentum generally became more fully accommodated. For each momentum coefficient, an empirical correlation function was obtained which closely approximated the experimental results over the ranges of energy and incidence angle. Most of the observed variations of momentum accommodation with energy and incidence angle were qualitatively indicated by a calculation using a three-dimensional model that simulated the target surface by a one-dimensional attractive potential and hard sphere reflectors.

  5. 46 CFR 127.260 - Ventilation for accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation for accommodations. 127.260 Section 127.260... ARRANGEMENTS Particular Construction and Arrangements § 127.260 Ventilation for accommodations. (a) Each... vessel of 100 or more gross tons must be provided with a mechanical ventilation system unless the...

  6. The provision of workplace accommodations following cancer: survivor, provider, and employer perspectives.

    PubMed

    Stergiou-Kita, Mary; Pritlove, Cheryl; van Eerd, Dwayne; Holness, Linn D; Kirsh, Bonnie; Duncan, Andrea; Jones, Jennifer

    2016-06-01

    With improvements in screening, diagnosis, and treatment, the number of persons surviving cancer and staying at or returning to work is increasing. While workplace accommodations optimize workers' abilities to participate in the workforce, there has been little in-depth investigation of the types of accommodations reported to have been provided to cancer survivors and the processes relevant to ensuring their successful implementation. We employed an exploratory qualitative method and conducted 40 semi-structured interviews with three groups: (i) cancers survivors (n = 16), (ii) health/vocational service providers (n = 16), and (iii) employer representatives (n = 8) to explore return to work and accommodation processes, successes, and challenges. An inductive thematic analysis approach was used to analyze the data. Four types of accommodations were recommended: (1) graduated return to work plans and flexible scheduling, (2) modification of work duties and performance expectations, (3) retraining and supports at the workplace, and (4) modification of the physical work environment and/or the provision of adaptive aids/technologies. Processes relevant to ensuring effective accommodations included: (1) developing knowledge about accommodations, (2) employer's ability to accommodate, (3) negotiating reasonable accommodations, (4) customizing accommodations, and (5) implementing and monitoring accommodation plans. Accommodation challenges included: (1) survivors' fears requesting accommodations, (2) developing clear and specific accommodations, (3) difficult to accommodate jobs, and (4) workplace challenges, including strained pre-cancer workplace relationships, insufficient/inflexible workplace policies, employer concerns regarding productivity and precedent setting, and limited modified duties. Accommodations need to be customized and clearly linked to survivors' specific job demands, work context, and available workplace supports. Survivors need to feel

  7. Utility accommodation and conflict tracker (UACT) : user manual

    DOT National Transportation Integrated Search

    2009-02-01

    Project 0-5475 performed a comprehensive analysis of utility conflict data/information flows between utility : accommodation stakeholders in the Texas Department of Transportation project development process, : developed data models to accommodate wo...

  8. 46 CFR 30.10-2 - Accommodation space-TB/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Accommodation space-TB/ALL. 30.10-2 Section 30.10-2... Accommodation space—TB/ALL. The term accommodation space means any public space such as a hall, dining room... that contains no cooking appliances, and a similar space open to the passengers and crew. [CGD 74-127...

  9. 46 CFR 30.10-2 - Accommodation space-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Accommodation space-TB/ALL. 30.10-2 Section 30.10-2... Accommodation space—TB/ALL. The term accommodation space means any public space such as a hall, dining room... that contains no cooking appliances, and a similar space open to the passengers and crew. [CGD 74-127...

  10. 46 CFR 30.10-2 - Accommodation space-TB/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Accommodation space-TB/ALL. 30.10-2 Section 30.10-2... Accommodation space—TB/ALL. The term accommodation space means any public space such as a hall, dining room... that contains no cooking appliances, and a similar space open to the passengers and crew. [CGD 74-127...

  11. 46 CFR 30.10-2 - Accommodation space-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Accommodation space-TB/ALL. 30.10-2 Section 30.10-2... Accommodation space—TB/ALL. The term accommodation space means any public space such as a hall, dining room... that contains no cooking appliances, and a similar space open to the passengers and crew. [CGD 74-127...

  12. 46 CFR 30.10-2 - Accommodation space-TB/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Accommodation space-TB/ALL. 30.10-2 Section 30.10-2... Accommodation space—TB/ALL. The term accommodation space means any public space such as a hall, dining room... that contains no cooking appliances, and a similar space open to the passengers and crew. [CGD 74-127...

  13. Accommodating Picky Palates

    ERIC Educational Resources Information Center

    Lum, Lydia

    2007-01-01

    Healthy gourmet offerings are fast becoming the norm at college dining halls around the country. At a time when the children of Baby Boomers are hitting higher education in record numbers, college officials have scrambled to accommodate their picky palates and their insistence for healthier meals than were served to past generations. At the same…

  14. Prediction of anthropometric accommodation in aircraft cockpits

    NASA Astrophysics Data System (ADS)

    Zehner, Gregory Franklin

    Designing aircraft cockpits to accommodate the wide range of body sizes existing in the U.S. population has always been a difficult problem for Crewstation Engineers. The approach taken in the design of military aircraft has been to restrict the range of body sizes allowed into flight training, and then to develop standards and specifications to ensure that the majority of the pilots are accommodated. Accommodation in this instance is defined as the ability to: (1) Adequately see, reach, and actuate controls; (2) Have external visual fields so that the pilot can see to land, clear for other aircraft, and perform a wide variety of missions (ground support/attack or air to air combat); and (3) Finally, if problems arise, the pilot has to be able to escape safely. Each of these areas is directly affected by the body size of the pilot. Unfortunately, accommodation problems persist and may get worse. Currently the USAF is considering relaxing body size entrance requirements so that smaller and larger people could become pilots. This will make existing accommodation problems much worse. This dissertation describes a methodology for correcting this problem and demonstrates the method by predicting pilot fit and performance in the USAF T-38A aircraft based on anthropometric data. The methods described can be applied to a variety of design applications where fitting the human operator into a system is a major concern. A systematic approach is described which includes: defining the user population, setting functional requirements that operators must be able to perform, testing the ability of the user population to perform the functional requirements, and developing predictive equations for selecting future users of the system. Also described is a process for the development of new anthropometric design criteria and cockpit design methods that assure body size accommodation is improved in the future.

  15. Evidence that convergence rather than accommodation controls intermittent distance exotropia

    PubMed Central

    Horwood, Anna M; Riddell, Patricia M

    2015-01-01

    Purpose This study considered whether vergence drives accommodation or accommodation drives vergence during the control of distance exotropia for near fixation. High accommodative convergence to accommodation (AC/A) ratios are often used to explain this control, but the role of convergence to drive accommodation (the CA/C relationship) is rarely considered. Atypical CA/C characteristics could equally, or better, explain common clinical findings. Methods 19 distance exotropes, aged 4-11 years, were compared while controlling their deviation with 27 non-exotropic controls aged 5-9 years. Simultaneous vergence and accommodation responses were measured to a range of targets incorporating different combinations of blur, disparity and looming cues at four fixation distances between 2m and 33cm. Stimulus and response AC/A and CA/C ratios were calculated. Results Accommodation responses for near targets (p=0.017) response gains (p=0.026) were greater in the exotropes than the controls. Despite higher clinical stimulus AC/A ratios, the distance exotropes showed lower laboratory response AC/A ratios (p=0.02), but significantly higher CA/C ratios (p=0.02). All the exotropes, whether the angle changed most with lenses (“controlled by accommodation”) or on occlusion (“controlled by fusion”), used binocular disparity not blur as their main cue to target distance. Conclusions Increased vergence demand to control intermittent distance exotropia for near also drives significantly more accommodation. Minus lens therapy is more likely to act by correcting over-accommodation driven by controlling convergence, rather than by inducing blur-driven vergence. The use of convergence as a major drive to accommodation explains many clinical characteristics of distance exotropia, including apparently high near stimulus AC/A ratios. PMID:22280437

  16. Accommodation measurements of horizontally scanning holographic display.

    PubMed

    Takaki, Yasuhiro; Yokouchi, Masahito

    2012-02-13

    Eye accommodation is considered to function properly for three-dimensional (3D) images generated by holography. We developed a horizontally scanning holographic display technique that enlarges both the screen size and viewing zone angle. A 3D image generated by this technique can be easily seen by both eyes. In this study, we measured the accommodation responses to a 3D image generated by the horizontally scanning holographic display technique that has a horizontal viewing zone angle of 14.6° and screen size of 4.3 in. We found that the accommodation responses to a 3D image displayed within 400 mm from the display screen were similar to those of a real object.

  17. Choosing Accommodations: Signed Language Interpreting and the Absence of Choice.

    PubMed

    Burke, Teresa Blankmeyer

    This paper carves out a topic space for discussion about the ethical question of whether input from signing Deaf consumers of interpreting services ought to be included in the provision of signed language interpreter accommodations. The first section provides background about disability accommodations and practices, including how signed language interpreting accommodations are similar and dissimilar to other kinds of disability accommodations. In the second section, I offer a personal narrative of my experience as a Deaf academic who has been excluded from the interpreter selection process, highlighting some of the harmful consequences of such exclusion. In the subsequent two sections, I describe and analyze the process of choosing interpreter accommodations, starting with the process of requesting signed language interpreters and the institutionalization of this process, followed by a brief overview of privacy and autonomy concerns from the standpoint of the signing Deaf consumer. The penultimate section considers some objections to the proposal of involving more consumer choice in signed language accommodations. I conclude the paper with some concrete suggestions for a more Deaf-centered, inclusive process for choosing interpreter accommodations.

  18. The effect of incipient presbyopia on the correspondence between accommodation and vergence.

    PubMed

    Baker, Fiona J; Gilmartin, Bernard

    2002-06-01

    To investigate the accommodation-convergence relationship during the incipient phase of presbyopia. The study aimed to differentiate between the current theories of presbyopia and to explore the mechanisms by which the oculomotor system compensates for the change in the accommodation-convergence relationship contingent on a declining amplitude of accommodation. Using a Canon R-1 open-view autorefractor and a haploscope device, measurements were made of the stimulus and response accommodative convergence/accommodation ratios and the convergence accommodation/convergence ratio of 28 subjects aged 35-45 years at the commencement of the study. Amplitude of accommodation was assessed using a push-down technique. The measurements were repeated at 4-monthly intervals over a 2-year period. The results showed that with the decline in the amplitude of accommodation there is an increase in the accommodative convergence response per unit of accommodative response and a decrease in the convergence accommodation response per unit of convergence. The results of this study fail to support the Hess-Gullstrand theory of presbyopia in that the ciliary muscle effort required to produce a unit change in accommodation increases, rather than stays constant, with age. Data show that the near vision response is limited to the maximum vergence response that can be tolerated and, despite being within the amplitude of accommodation, a stimulus may still appear blurred because the vergence component determines the proportion of available accommodation utilised during near vision.

  19. Wavefront aberration changes caused by a gradient of increasing accommodation stimuli

    PubMed Central

    Zhou, X-Y; Wang, L; Zhou, X-T; Yu, Z-Q

    2015-01-01

    Purpose The aim of this study was to investigate the wavefront aberration changes in human eyes caused by a gradient of increasing accommodation stimuli. Design This is a prospective, single-site study. Methods Healthy volunteers (n=22) aged 18–28 years whose refraction states were emmetropia or mild myopia, with astigmatism <1 diopter (D), were included in this study. After dilating the right pupil with 0.5% phenylephrine drops, the wavefront aberration of the right eye was measured continuously either without or with 1, 2, 3, 4, 5, or 6D accommodation stimuli (WFA1000B psychophysical aberrometer). The root mean square (RMS) values of the total wavefront aberrations, higher-order aberrations, and 35 individual Zernike aberrations under different accommodation stimuli were calculated and compared. Results The average induced accommodations using 1, 2, 3, 4, 5, or 6D accommodation stimuli were 0.848, 1.626, 2.375, 3.249, 4.181, or 5.085 D, respectively. The RMS of total wavefront aberrations, as well as higher-order aberrations, showed no significant effects with 1–3 D accommodation stimuli, but increased significantly under 4, 5, and 6 D accommodation stimuli compared with relaxed accommodation. Zernike coefficients of significantly decreased with increasing levels of accommodation. Conclusion Higher-order wavefront aberrations in human eyes changed with increased accommodation. These results are consistent with Schachar's accommodation theory. PMID:25341432

  20. Occlusal accommodation and mouthguards for prevention of orofacial trauma.

    PubMed

    Geary, Julian Lindsay; Clifford, Thomas Joseph; Kinirons, Martin James

    2009-01-01

    The aim of this study was to investigate the effect of two types of occlusal accommodation on the arch separation in centric and eccentric arch positions and to assess the opposing tooth contacts in professionally made, thermoformed sports mouthguards. Maxillary and mandibular alginate impressions, a wax interocclusal record of centric occlusion together with maxillary/condylar face-bow registrations, were recorded clinically for 10 undergraduate dental students who are sports activist volunteers of the School of Medicine and Dentistry, Queen's University Belfast. Two ethylene vinyl acetate thermoformed maxillary mouthguards were made for each player (N = 20) using a standardised procedure. Ten mouthguards served both as the control (i.e. the non-accommodated) group and also the accommodated, occlusally 'imprinted' group. The other 10 mouthguards served as the accommodated, occlusally 'ground' group. Casts were articulated, each non-accommodated and accommodated mouthguard was seated and the extent of the interocclusal opening was recorded in all three arch relationships. The number of mouthguard and mandibular tooth contacts were also recorded in each position. The increased vertical occlusal dimension that was found in the presence of non-accommodated mouthguards equated to the full-sheet thickness of the material that was used to form the mouthguards. Only mouthguards accommodated by grinding retained high levels of occlusal contact in all arch relationships that were tested. Within the limitations of this study, the modification of the occlusal surface made by flat grinding reduced the arch separation in eccentric movements and increased the opposing tooth contacts in custom-made mouthguards. This may contribute to increased comfort, compliance and the protective effect of these appliances thus resulting in a reduction of injuries to the teeth, arches and soft tissues.

  1. Human dynamic closed-loop accommodation augmented by sympathetic inhibition.

    PubMed

    Culhane, H M; Winn, B; Gilmartin, B

    1999-05-01

    A ciliary alpha-adrenoceptor accommodative effect has been proposed, caused by a small population of alpha1-inhibitory receptors in excised human ciliary muscle. This study was intended to investigate the effect on the closed-loop dynamic accommodative process of modulating alpha1-adrenoceptor activity by topical instillation of the alpha1-adrenergic agonist, phenylephrine hydrochloride. A group of 10 visually normal subjects viewed a photopic (30 candela/m2) high-contrast Maltese cross, which was modulated sinusoidally (0.05-0.6Hz) and stepwise over a 2-D range (2-4 D). Monocular temporal accommodation responses were measured using a continuously recording dynamic tracking infrared optometer under two trial conditions: after instillation of saline control solution and 50 minutes subsequent to the instillation of 0.27 microl 0.4% benoxinate hydrochloride and 0.27 microl 2.5% phenylephrine hydrochloride. Pupil size and accommodative amplitude were measured at 90-second intervals for 50 minutes after drug instillation. All accommodative measurements were recorded through a fixed 4-mm pupil. A significant reduction in accommodative amplitude (11%; P < 0.05) was recorded, whereas pupil size showed a significant increase (33%; P < 0.05). No significant change in step-response dynamics was observed. However, phenylephrine hydrochloride caused a significant increase in accommodative gain in the low and midtemporal frequency ranges compared with the effect of a saline control treatment. No significant variation in phase lag was observed. For the first time in humans, this study shows that augmentation of the alpha1-inhibitory sympathetic contribution results in increased accommodative gain at low and midtemporal frequencies, which is consistent with findings in animal studies.

  2. Comparison of tests of accommodation for computer users.

    PubMed

    Kolker, David; Hutchinson, Robert; Nilsen, Erik

    2002-04-01

    With the increased use of computers in the workplace and at home, optometrists are finding more patients presenting with symptoms of Computer Vision Syndrome. Among these symptomatic individuals, research supports that accommodative disorders are the most common vision finding. A prepresbyopic group (N= 30) and a presbyopic group (N = 30) were selected from a private practice. Assignment to a group was determined by age, accommodative amplitude, and near visual acuity with their distance prescription. Each subject was given a thorough vision and ocular health examination, then administered several nearpoint tests of accommodation at a computer working distance. All the tests produced similar results in the presbyopic group. For the prepresbyopic group, the tests yielded very different results. To effectively treat symptomatic VDT users, optometrists must assess the accommodative system along with the binocular and refractive status. For presbyopic patients, all nearpoint tests studied will yield virtually the same result. However, the method of testing accommodation, as well as the test stimulus presented, will yield significantly different responses for prepresbyopic patients. Previous research indicates that a majority of patients prefer the higher plus prescription yielded by the Gaussian image test.

  3. Accommodation in pediatric oncology: parental experiences, preferences and unmet needs.

    PubMed

    Daniel, Gunar; Wakefield, Claire E; Ryan, Barbara; Fleming, Catharine Ak; Levett, Nicole; Cohn, Richard J

    2013-01-01

    For families of children diagnosed with cancer, proximity to the treatment center and staying close to immediate family members are essential for proper patient management. Accommodation services are therefore a key consideration in pediatric oncology. This descriptive study explored the accommodation used, and preferred, by parents of pediatric cancer patients at Sydney Children's Hospital, Randwick (SCH), Australia, and investigated their accommodation and practical needs. Forty-two parents from 25 families participated in individual semi-structured telephone interviews. Interviews were recorded, transcribed verbatim and coded line-by-line. Coding was facilitated by data analysis software QSR NVivo v8 (www.qsrinternational.com). Emergent themes were numerically assessed to minimize the potential for researcher bias. Nine families (36%) lived near SCH and were able to stay at their own residence during treatment (mean distance of 15.4 km from SCH). The remaining families were categorized 'local, but requiring accommodation' (n=3 families represented by five parent interviews; mean distance of 82.22 km from SCH),'inner regional' (IR) (n=8 families, 15 parent interviews; mean distance of 396.75 km from SCH) or 'outer regional' (OR) (n=3 families, 5 interviews; mean distance of 547.4 km from SCH) according to the Australian Standard Geographical Classification (ASGC) remoteness ratings. Accommodation provided for families from both IR and OR areas was mixed, with several families using multiple accommodation options during treatment, including Ronald Macdonald House (RMH), private accommodation or a rental property close to the hospital for the duration of the treatment. Six IR and one OR family utilized hotel or motel accommodation as an alternative to RMH due to unavailability of rooms. The majority of parents (37/42) preferred to stay on the hospital campus, near their child. Seven out of 11 IR and OR mothers preferred self-contained accommodation, while three out

  4. Accommodation and vergence latencies in human infants

    PubMed Central

    Tondel, Grazyna M.; Candy, T. Rowan

    2008-01-01

    Purpose Achieving simultaneous single and clear visual experience during postnatal development depends on the temporal relationship between accommodation and vergence, in addition to their accuracies. This study was designed to examine one component of the dynamic relationship, the latencies of the responses. Methods Infants and adults were tested in three conditions i) Binocular viewing of a target moving in depth at 5cm/s (closed loop) ii) monocular viewing of the same target (vergence open loop) iii) binocular viewing of a low spatial frequency Difference of Gaussian target during a prism induced step change in retinal disparity (accommodation open loop). Results There was a significant correlation between accommodation and vergence latencies in binocular conditions for infants from 7 to 23 weeks of age. Some of the infants, as young as 7 or 8 weeks, generated adult-like latencies of less than 0.5 s. Latencies in the vergence open loop and accommodation open loop conditions tended to be shorter for the stimulated system than the open loop system in both cases, and all latencies were typically less than 2 seconds across the infant age range. Conclusions Many infants between 7 and 23 weeks of age were able to generate accommodation and vergence responses with latencies of less than a second in full binocular closed loop conditions. The correlation between the latencies in the two systems suggests that they are limited by related factors from the earliest ages tested. PMID:18199466

  5. Accommodation and vergence latencies in human infants.

    PubMed

    Tondel, Grazyna M; Candy, T Rowan

    2008-02-01

    Achieving simultaneous single and clear visual experience during postnatal development depends on the temporal relationship between accommodation and vergence, in addition to their accuracies. This study was designed to examine one component of the dynamic relationship, the latencies of the responses. Infants and adults were tested in three conditions (i) binocular viewing of a target moving in depth at 5 cm/s (closed loop) (ii) monocular viewing of the same target (vergence open loop) (iii) binocular viewing of a low spatial frequency Difference of Gaussian target during a prism induced step change in retinal disparity (accommodation open loop). There was a significant correlation between accommodation and vergence latencies in binocular conditions for infants from 7 to 23 weeks of age. Some of the infants, as young as 7 or 8 weeks, generated adult-like latencies of less than 0.5 s. Latencies in the vergence open loop and accommodation open loop conditions tended to be shorter for the stimulated system than the open loop system in both cases, and all latencies were typically less than 2 s across the infant age range. Many infants between 7 and 23 weeks of age were able to generate accommodation and vergence responses with latencies of less than a second in full binocular closed loop conditions. The correlation between the latencies in the two systems suggests that they are limited by related factors from the earliest ages tested.

  6. A model to predict accommodations needed by disabled persons.

    PubMed

    Babski-Reeves, Kari; Williams, Sabrina; Waters, Tzer Nan; Crumpton-Young, Lesia L; McCauley-Bell, Pamela

    2005-09-01

    In this paper, several approaches to assist employers in the accommodation process for disabled employees are discussed and a mathematical model is proposed to assist employers in predicting the accommodation level needed by an individual with a mobility-related disability. This study investigates the validity and reliability of this model in assessing the accommodation level needed by individuals utilizing data collected from twelve individuals with mobility-related disabilities. Based on the results of the statistical analyses, this proposed model produces a feasible preliminary measure for assessing the accommodation level needed for persons with mobility-related disabilities. Suggestions for practical application of this model in an industrial setting are addressed.

  7. Evidence that convergence rather than accommodation controls intermittent distance exotropia.

    PubMed

    Horwood, Anna M; Riddell, Patricia M

    2012-03-01

    This study considered whether vergence drives accommodation or accommodation drives vergence during the control of distance exotropia for near fixation. High accommodative convergence to accommodation (AC/A) ratios are often used to explain this control, but the role of convergence to drive accommodation (the CA/C relationship) is rarely considered. Atypical CA/C characteristics could equally, or better, explain common clinical findings. Nineteen distance exotropes, aged 4-11 years, were compared while controlling their deviation with 27 non-exotropic controls aged 5-9 years. Simultaneous vergence and accommodation responses were measured to a range of targets incorporating different combinations of blur, disparity and looming cues at four fixation distances between 2 m and 33 cm. Stimulus and response AC/A and CA/C ratios were calculated. Accommodation responses for near targets (p = 0.017) and response gains (p = 0.026) were greater in the exotropes than in the controls. Despite higher clinical stimulus AC/A ratios, the distance exotropes showed lower laboratory response AC/A ratios (p = 0.02), but significantly higher CA/C ratios (p = 0.02). All the exotropes, whether the angle changed most with lenses ('controlled by accommodation') or on occlusion ('controlled by fusion'), used binocular disparity not blur as their main cue to target distance. Increased vergence demand to control intermittent distance exotropia for near also drives significantly more accommodation. Minus lens therapy is more likely to act by correcting overaccommodation driven by controlling convergence, rather than by inducing blur-driven vergence. The use of convergence as a major drive to accommodation explains many clinical characteristics of distance exotropia, including apparently high near stimulus AC/A ratios. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

  8. Accommodation and Phoria in Children Wearing Multifocal Contact Lenses

    PubMed Central

    Gong, Celia R; Troilo, David; Richdale, Kathryn

    2017-01-01

    Purpose To determine the effect of multifocal contact lenses on accommodation and phoria in children. Methods This was a prospective, non-dispensing, randomized, crossover, single visit study. Myopic children with normal accommodation and binocularity and no history of myopia control treatment were enrolled and fitted with Coopervision Biofinity single vision (SV) and multifocal (MF, +2.50D center distance add) contact lenses. Accommodative responses (photorefraction) and phorias (Modified Thorington) were measured at 4 distances (>3m, 100cm, 40cm, 25cm). Secondary measures included high and low contrast logMAR acuity, accommodative amplitude and facility. Differences between contact lens designs were analyzed using repeated measures regression and paired t-tests. Results A total of 16 subjects, aged 10-15 years, completed the study. There was a small decrease in high (SV: -0.08, MF: +0.01) and low illumination (SV:-0.03, MF: +0.08) (both p<0.01) visual acuity, and contrast sensitivity (SV: 2.0, MF: 1.9 log units, p=0.015) with multifocals. Subjects were more exophoric at 40 cm (SV: -0.41, MF: -2.06 Δ) and 25cm (SV: -0.83, MF: -4.30 Δ) (both p<0.01). With multifocals, subjects had decreased accommodative responses at distance (SV: -0.04; MF: -0.37 D, p=0.02), 100 cm (SV: +0.37; MF: -0.35 D, p<0.01), 40 cm (SV: +1.82; MF: +0.62 D, p<0.01), and 25 cm (SV: +3.38; MF: +1.75 D, p<0.01). There were no significant differences in accommodative amplitude (p=0.66) or facility (p=0.54). Conclusions Children wearing multifocal contact lenses exhibited reduced accommodative responses and more exophoria at increasingly higher accommodative demands than with single vision contact lenses. This suggests that children may be relaxing their accommodation and using the positive addition or increased depth of focus from added spherical aberration of the multifocals. Further studies are needed to evaluate other lens designs, different amounts of positive addition and aberrations, and

  9. Study on accommodation by autorefraction and dynamic refraction in children.

    PubMed

    Krishnacharya, Prabhakar Srinivasapur

    2014-01-01

    Childhood accommodation interferes with accurate diagnosis of the latent refractive errors. Dynamic retinoscopy offers accurate measurements of accommodative response, while an autorefractometer can predict the accommodative system activation in children. A correlation of the accommodative effort with the dynamic refraction has been investigated in emmetropic children, before and after cycloplegia. A prospective clinical study of accommodative effort in 149 emmetropic children, in the age group 3-16 years, has been conducted using TOPCON AR RM-8000B autorefractor. Dynamic refraction was performed by monocular estimation method before and after cycloplegia, using the retinoscope mirror light as target. Retinoscopic reflex produced 'with the motion' was corrected with positive spherical lenses, and that 'against the motion' was corrected with negative spherical lenses, to achieve neutralization. Mean accommodative effort measured for 149 children included in the study was -0.63±0.69D and dynamic refraction was -0.07±0.44D before cycloplegia, while the mean was+0.52D after cycloplegia, irrespective of the method used. Autorefractor measured -0.17D of accommodative effort per unit change in dynamic refraction before cycloplegia and +0.90D after cycloplegia. The performance of TOPCON AR RM-8000B autorefractor was comparable to dynamic retinoscopy. Presence of many children, and in turn, large number of accommodative response data in 11-13 and 14-15 years group is probably linked to prolonged reading/writing. The accuracy and the agreement of the actual accommodative measurements revealed after cycloplegia. Copyright © 2013 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  10. Carbonate Platform Development and Stromatolite Morphogenesis: Constraints on Environmental and Biological Evolution

    NASA Technical Reports Server (NTRS)

    Grotzinger, John P.

    2003-01-01

    Work has been completed on the digital mapping of a terminal Proterozoic reef complex in Namibia. This complex formed an isolated carbonate platform developed downdip on a carbonate ramp of the Nama Group. The stratigraphic evolution of the platform was digitally reconstructed from an extensive dataset that was compiled by using digital surveying technologies. The platform comprises three accommodation cycles in which each subsequent cycle experienced progressively greater influence of a long-term accommodation increase. Aggradation and progradation during the first cycle resulted in a flat, uniform, sheet-like platform. The coarsening and shallowing-upward sequence representing the first cycle is dominated by columnar stromatolitic thrombolites and massive dolostones with interbedded mudstone-grainstone at the base of the sequence grading into cross-bedded dolostones. The second cycle features aggradation, formation of a distinct margin containing thrombolite mounds and domes, and the development of a bucket geometry. Columnar stromatolitic thrombolites dominate the platform interior. The final stage of platform development shows a deepening trend with initial aggradation and formation of well-bedded, thin deposits in the interior and mound development at the margins. While the interior drowned, the platform margin kept up with rising sea level and a complex pinnacle reef formed containing fused and coalesced thrombolite mounds flanked by bioclastic grainstones (containing Cloudina and Namacalathus fossils) and collapse breccias. A set of isolated large thrombolite mounds flanked by shales indicate the final stage of the carbonate platform. During a progressive increase in accommodation, a flat-topped isolated carbonate platform becomes aerially less extensive by either backstepping or formation of smaller pinnacles or a combination of both. The overall geometric evolution of the studied platform from flat-topped to bucket with elevated margins is recorded in many

  11. Accommodation Practices for English Language Learners in States' Mathematics Assessments

    ERIC Educational Resources Information Center

    Wolf, Mikyung Kim; Kao, Jenny C.; Rivera, Nichole M.; Chang, Sandy M.

    2012-01-01

    Background/Context: Testing accommodations have been widely utilized as a way of increasing the validity of content assessments for English language learner (ELL) students. However, concerns have also arisen regarding the appropriateness of accommodation use, including the accessibility and fairness of accommodations. While many states have…

  12. Against the accommodation of subjective healthcare provider beliefs in medicine: counteracting supporters of conscientious objector accommodation arguments.

    PubMed

    Smalling, Ricardo; Schuklenk, Udo

    2017-04-01

    We respond in this paper to various counter arguments advanced against our stance on conscientious objection accommodation. Contra Maclure and Dumont, we show that it is impossible to develop reliable tests for conscientious objectors' claims with regard to the reasonableness of the ideological basis of their convictions, and, indeed, with regard to whether they actually hold they views they claim to hold. We demonstrate furthermore that, within the Canadian legal context, the refusal to accommodate conscientious objectors would not constitute undue hardship for such objectors. We reject concerns that refusing to accommodate conscientious objectors would limit the equality of opportunity for budding professionals holding particular ideological positions. We also clarify various misrepresentations of our views by respondents Symons, Glick and Jotkowitz, and Lyus. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  13. The rate of change of vergence-accommodation conflict affects visual discomfort.

    PubMed

    Kim, Joohwan; Kane, David; Banks, Martin S

    2014-12-01

    Stereoscopic (S3D) displays create conflicts between the distance to which the eyes must converge and the distance to which the eyes must accommodate. Such conflicts require the viewer to overcome the normal coupling between vergence and accommodation, and this effort appears to cause viewer discomfort. Vergence-accommodation coupling is driven by the phasic components of the underlying control systems, and those components respond to relatively fast changes in vergence and accommodative stimuli. Given the relationship between phasic changes and vergence-accommodation coupling, we examined how the rate of change in the vergence-accommodation conflict affects viewer discomfort. We used a stereoscopic display that allows independent manipulation of the stimuli to vergence and accommodation. We presented stimuli that simulate natural viewing (i.e., vergence and accommodative stimuli changed together) and stimuli that simulate S3D viewing (i.e., vergence stimulus changes but accommodative stimulus remains fixed). The changes occurred at 0.01, 0.05, or 0.25 Hz. The lowest rate is too slow to stimulate the phasic components while the highest rate is well within the phasic range. The results were consistent with our expectation: somewhat greater discomfort was experienced when stimulus distance changed rapidly, particularly in S3D viewing when the vergence stimulus changed but the accommodative stimulus did not. These results may help in the generation of guidelines for the creation and viewing of stereo content with acceptable viewer comfort.

  14. The Rate of Change of Vergence-Accommodation Conflict Affects Visual Discomfort

    PubMed Central

    Kane, David; Banks, Martin S.

    2014-01-01

    Stereoscopic (S3D) displays create conflicts between the distance to which the eyes must converge and the distance to which the eyes must accommodate. Such conflicts require the viewer to overcome the normal coupling between vergence and accommodation, and this effort appears to cause viewer discomfort. Vergence-accommodation coupling is driven by the phasic components of the underlying control systems, and those components respond to relatively fast changes in vergence and accommodative stimuli. Given the relationship between phasic changes and vergence-accommodation coupling, we examined how the rate of change in the vergence-accommodation conflict affects viewer discomfort. We used a stereoscopic display that allows independent manipulation of the stimuli to vergence and accommodation. We presented stimuli that simulate natural viewing (i.e., vergence and accommodative stimuli changed together) and stimuli that simulate S3D viewing (i.e., vergence stimulus changes but accommodative stimulus remains fixed). The changes occurred at 0.01, 0.05, or 0.25Hz. The lowest rate is too slow to stimulate the phasic components while the highest rate is well within the phasic range. The results were consistent with our expectation: somewhat greater discomfort was experienced when stimulus distance changed rapidly, particularly in S3D viewing when the vergence stimulus changed but the accommodative stimulus did not. These results may help in the generation of guidelines for the creation and viewing of stereo content with acceptable viewer comfort. PMID:25448713

  15. Study on accommodation by autorefraction and dynamic refraction in children

    PubMed Central

    Krishnacharya, Prabhakar Srinivasapur

    2014-01-01

    Purpose Childhood accommodation interferes with accurate diagnosis of the latent refractive errors. Dynamic retinoscopy offers accurate measurements of accommodative response, while an autorefractometer can predict the accommodative system activation in children. A correlation of the accommodative effort with the dynamic refraction has been investigated in emmetropic children, before and after cycloplegia. Methods A prospective clinical study of accommodative effort in 149 emmetropic children, in the age group 3–16 years, has been conducted using TOPCON AR RM-8000B autorefractor. Dynamic refraction was performed by monocular estimation method before and after cycloplegia, using the retinoscope mirror light as target. Retinoscopic reflex produced ‘with the motion’ was corrected with positive spherical lenses, and that ‘against the motion’ was corrected with negative spherical lenses, to achieve neutralization. Results Mean accommodative effort measured for 149 children included in the study was −0.63 ± 0.69 D and dynamic refraction was −0.07 ± 0.44 D before cycloplegia, while the mean was + 0.52 D after cycloplegia, irrespective of the method used. Autorefractor measured −0.17 D of accommodative effort per unit change in dynamic refraction before cycloplegia and +0.90 D after cycloplegia. Conclusions The performance of TOPCON AR RM-8000B autorefractor was comparable to dynamic retinoscopy. Presence of many children, and in turn, large number of accommodative response data in 11–13 and 14–15 years group is probably linked to prolonged reading/writing. The accuracy and the agreement of the actual accommodative measurements revealed after cycloplegia. PMID:25130066

  16. The impact of testing accommodations on MCAT scores: descriptive results.

    PubMed

    Julian, Ellen R; Ingersoll, Deborah J; Etienne, Patricia M; Hilger, Anthony E

    2004-04-01

    Medical College Admission Test (MCAT) examinees with disabilities who receive accommodations receive flagged scores indicating nonstandard administration. This report compares MCAT examinees who received accommodations and their performances with standard examinees. Aggregate history records of all 1994-2000 MCAT examinees were identified as flagged (2,401) or standard (297,880), then further sorted by race/ethnicity (broadly identified as underrepresented minority and non-URM, at the time of testing) and gender. Those with flagged scores were also classified by disability (LD = learning disability, ADHD = attention deficit hyperactivity disorder, LD/ADHD = learning disability and attention deficit hyperactivity disorder, and Other = other disability) and type of accommodation. Mean MCAT scores were calculated for all groups. A group of 866 examinees took the MCAT first as a standard administration and subsequently with accommodations. In a separate analysis, their two sets of scores were compared. Less than 1% of examinees (2,401) had accommodations; of these, 55% were LD, 17% ADHD, 5% LD/ADHD, and 23% Other. Extended time was the most frequently provided accommodation. Mean flagged scores slightly exceeded mean standard scores on all MCAT sections. Examinees who retook the MCAT with accommodations after a standard administration increased their scores by six points, quadrupling the average gain Standard-Standard retest cohort from another study. The small but statistically significant different higher flagged scores may reflect either appropriate compensation or overly generous accommodations. Extended time had a positive impact on the scores of those who retested with this accommodation. The validity the flagged MCAT in predicting success in medical school is not known, and further investigation is underway.

  17. A meta-analysis of family accommodation and OCD symptom severity.

    PubMed

    Wu, Monica S; McGuire, Joseph F; Martino, Charitie; Phares, Vicky; Selles, Robert R; Storch, Eric A

    2016-04-01

    Family accommodation in obsessive-compulsive disorder (OCD) is characterized by myriad behaviors, such as modifying family routines, facilitating avoidance, and engaging in compulsions to reduce obsessional distress. It has been linked to various deleterious outcomes including increased functional impairment and poorer treatment response for OCD. Although extant literature suggests a linear relationship between family accommodation and OCD symptom severity, the magnitude and statistical significance of this association has been inconsistent across studies, indicating that moderators may be influencing this relationship. The present study examined this relationship using meta-analytic techniques, and investigated sample-dependent (age, gender, comorbid anxiety/mood disorders) and methodological (administration method and number of items used in family accommodation measure, informant type, sample size, publication year) moderators. Forty-one studies were included in the present meta-analysis, and the overall effect size (ES) for the correlation between family accommodation and OCD symptom severity was moderate (r=.42). Moderator analyses revealed that the number of items on the family accommodation scale moderated the ES. No other sample-dependent or methodological characteristics emerged as moderators. In addition to being the first systematic examination of family accommodation moderators, these results highlight the moderate relationship between family accommodation and OCD severity that is influenced by measurement scales. Findings may be used to guide clinical care and inform future investigations by providing a more nuanced understanding of family accommodation in OCD. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Water Accommodation on Bare and Coated Ice

    NASA Astrophysics Data System (ADS)

    Kong, Xiangrui

    2015-04-01

    A good understanding of water accommodation on ice surfaces is essential for quantitatively predicting the evolution of clouds, and therefore influences the effectiveness of climate models. However, the accommodation coefficient is poorly constrained within the literature where reported values vary by up to three orders of magnitude. In addition, the complexity of the chemical composition of the atmosphere plays an important role in ice phase behavior and dynamics. We employ an environmental molecular beam (EMB) technique to investigate molecular water interactions with bare and impurity coated ice at temperatures from 170 K to 200 K. In this work, we summarize results of water accommodation experiments on bare ice (Kong et al., 2014) and on ice coated by methanol (Thomson et al., 2013), butanol (Thomson et al., 2013) and acetic acid (Papagiannakopoulos et al., 2014), and compare those results with analogous experiments using hexanol and nitric acid coatings. Hexanol is chosen as a complementary chain alcohol to methanol and butanol, while nitric acid is a common inorganic compound in the atmosphere. The results show a strong negative temperature dependence of water accommodation on bare ice, which can be quantitatively described by a precursor model. Acidic adlayers tend to enhance water uptake indicating that the system kinetics are thoroughly changed compared to bare ice. Adsorbed alcohols influence the temperature dependence of the accommodation coefficient and water molecules generally spend less time on the surfaces before desorbing, although the measured accommodation coefficients remain high and comparable to bare ice for the investigated systems. We conclude that impurities can either enhance or restrict water uptake in ways that are influenced by several factors including temperature and type of adsorbant, with potential implications for the description of ice particle growth in the atmosphere. This work was supported by the Swedish Research Council and

  19. Spacelab payload accommodation handbook. Main volume

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The main characteristics of the Spacelab system are described to enable individual experimenters or payload planning groups to determine how their payload equipment can be accommodated by Spacelab. Spacelab/experiment interfaces, Spacelab payload support systems and requirements that the experiments have to comply with are described to allow experiment design and development. The basic operational aspects are outlined as far as they have an impact on experiment design. The relationship of the Spacelab Payload Accommodation Handbook to Space Transportation System documentation is outlined. Data concerning the space shuttle system are briefly described.

  20. An Accommodations Model for the Secondary Inclusive Classroom

    ERIC Educational Resources Information Center

    Scanlon, David; Baker, Diana

    2012-01-01

    Despite expectations for accommodations in inclusive classrooms, little guidance for effective practice is available. Most accommodations policies and evidence-based practices address assessments. High school regular and special educators collaborated in focus groups to articulate a model based on their practices and perceptions of best practice.…

  1. Religious Observance Accommodation in Ontario Universities. Discussion Paper.

    ERIC Educational Resources Information Center

    Reed, Carole Ann

    This paper highlights the religious accommodations that Ontario (Canada) universities have undertaken to create an inclusive, supportive learning community for all students, faculty, and staff. It outlines the demographic changes and public policy surrounding religious accommodation issues in Canada and in Ontario in particular, focusing on the…

  2. Gain and movement time of convergence-accommodation in preschool children.

    PubMed

    Suryakumar, R; Bobier, W R

    2004-11-01

    Convergence-accommodation is the synkinetic change in accommodation driven by vergence. A few studies have investigated the static and dynamic properties of this cross-link in adults but little is known about convergence-accommodation in children. The purpose of this study was to develop a technique for measuring convergence-accommodation and to study its dynamics (gain and movement time) in a sample of pre-school children. Convergence-accommodation measures were examined on thiry-seven normal pre-school children (mean age = 4.0 +/- 1.31 yrs). Stimulus CA/C (sCA/C) ratios and movement time measures of convergence-accommodation were assessed using a photorefractor while subjects viewed a DOG target. Repeated measures were obtained on eight normal adults (mean age = 23 +/- 0.2 yrs). The mean sCA/C ratios and movement times were not significantly different between adults and children (0.10 D/Delta [0.61 D/M.A.], 743 +/- 70 ms and 0.11 D/Delta [0.50 D/M.A.], 787 +/- 216 ms). Repeated measures on adults showed a non-significant mean difference of 0.001 D/Delta. The results suggest that the possible differences in crystalline lens (plant) characteristics between children and adults do not appear to influence convergence-accommodation gain or duration.

  3. Quick and Easy Adaptations and Accommodations for Early Childhood Students

    ERIC Educational Resources Information Center

    Breitfelder, Leisa M.

    2008-01-01

    Research-based information is used to support the idea of the use of adaptations and accommodations for early childhood students who have varying disabilities. Multiple adaptations and accommodations are outlined. A step-by-step plan is provided on how to make specific adaptations and accommodations to fit the specific needs of early childhood…

  4. Accommodative Behavior of Young Eyes Wearing Multifocal Contact Lenses.

    PubMed

    Altoaimi, Basal H; Almutairi, Meznah S; Kollbaum, Pete S; Bradley, Arthur

    2018-05-01

    The effectiveness of multifocal contact lenses (MFCLs) at slowing myopia progression may hinge on the accommodative behavior of young eyes fit with these presbyopic style lenses. Can they remove hyperopic defocus? Convergence accommodation as well as pupil size and the zonal geometry are likely to contribute to the final accommodative responses. The aim of this study was to examine the accommodation behavior of young adult eyes wearing MFCLs and the effectiveness of these MFCLs at removing foveal hyperopic defocus when viewing near targets binocularly. Using a high-resolution Shack-Hartmann aberrometer, accommodation and pupil behavior of eight young adults (27.25 ± 2.05 years) were measured while subjects fixated a 20/40 character positioned between 2 m and 20 cm (0.50 to 5.00 diopters [D]) in 0.25-D steps. Refractive states were measured while viewing binocularly and monocularly with single-vision and both center-distance and center-near +2.00 D add MFCLs. Refractive state was defined using three criteria: the dioptric power that would (1) minimize the root mean square wavefront error, (2) focus the pupil center, and (3) provide the peak image quality. Refractive state pupil maps reveal the complex optics that exist in eyes wearing MFCLs. Reduced accommodative gain beyond the far point of the near add revealed that young subjects used the added plus power to help focus near targets. During accommodation to stimuli closer than the far point generated by the add power, a midperipheral region of the pupil was approximately focused, resulting in the smallest accommodative errors for the minimum root mean square-defined measures of refractive state. Paraxial images were always hyperopically or myopically defocused in eyes viewing binocularly with center-distance or center-near MFCLs, respectively. Because of zone geometry in the concentric MFCLs tested, the highly aberrated transition zone between the distance and near optics contributed a significant proportion and

  5. The effect of proximity on open-loop accommodation responses measured with pinholes.

    PubMed

    Morrison, K A; Seidel, D; Strang, N C; Gray, L S

    2010-07-01

    Open-loop accommodation levels were measured in 41 healthy, young subjects using a Shin-Nippon SRW-5000 autorefractor in the three viewing conditions: a small physical pinhole pupil (SP), an optically projected pinhole in Maxwellian view (MV) and in the dark (DF). The target viewed through the pinholes was a high-contrast letter presented at 0 D vergence in a +5 D Badal lens system. Overall, results showed that SP open-loop accommodation levels were significantly higher than MV and DF levels. Subjects could be divided into two distinct subgroups according to their response behaviour: responders to the proximal effect of the small physical pinhole (SP accommodation > MV accommodation) and non-responders to the proximal effect of the small physical pinhole (SP accommodation approximately MV accommodation). Correlation analysis demonstrated that open-loop accommodation for both pinhole conditions was correlated with DF for the responders, while for the non-responders SP and MV accommodation were correlated, but were not related to DF accommodation. This suggests that under open-loop conditions some individuals' accommodation levels are mainly affected by proximal and cognitive factors (responders) while others are guided primarily by the presence of the more distal target (non-responders). In conclusion, MV reduces the proximal effect of the physical pinhole and produces open-loop accommodation responses which are more consistent than SP and DF responses.

  6. Are high lags of accommodation in myopic children due to motor deficits?

    PubMed

    Labhishetty, Vivek; Bobier, William R

    2017-01-01

    Children with a progressing myopia exhibit an abnormal pattern of high accommodative lags coupled with high accommodative convergence (AC/A) and high accommodative adaptation. This is not predicted by the current models of accommodation and vergence. Reduced accommodative plant gain and reduced sensitivity to blur have been suggested as potential causes for this abnormal behavior. These etiologies were tested by altering parameters (sensory, controller and plant gains) in the Simulink model of accommodation. Predictions were then compared to the static and dynamic blur accommodation (BA) measures taken using a Badal optical system on 12 children (6 emmetropes and 6 myopes, 8-13years) and 6 adults (20-35years). Other critical parameters such as CA/C, AC/A, and accommodative adaptation were also measured. Usable BA responses were classified as either typical or atypical. Typical accommodation data confirmed the abnormal pattern of myopia along with an unchanged CA/C. Main sequence relationship remained invariant between myopic and nonmyopic children. An overall reduction was noted in the response dynamics such as peak velocity and acceleration with age. Neither a reduced plant gain nor reduced blur sensitivity could predict the abnormal accommodative behavior. A model adjustment reflecting a reduced accommodative sensory gain (ASG) coupled with an increased AC cross-link gain and reduced vergence adaptive gain does predict the empirical findings. Empirical measures also showed a greater frequency of errors in accommodative response generation (atypical responses) in both myopic and control children compared to adults. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Convergence and Accommodation Development Is Preprogrammed in Premature Infants.

    PubMed

    Horwood, Anna M; Toor, Sonia S; Riddell, Patricia M

    2015-08-01

    This study investigated whether vergence and accommodation development in preterm infants is preprogrammed or is driven by experience. Thirty-two healthy infants, born at mean 34 weeks gestation (range, 31.2-36 weeks), were compared with 45 healthy full-term infants (mean 40.0 weeks) over a 6-month period, starting at 4 to 6 weeks postnatally. Simultaneous accommodation and convergence to a detailed target were measured using a Plusoptix PowerRefII infrared photorefractor as a target moved between 0.33 and 2 m. Stimulus/response gains and responses at 0.33 and 2 m were compared by both corrected (gestational) age and chronological (postnatal) age. When compared by their corrected age, preterm and full-term infants showed few significant differences in vergence and accommodation responses after 6 to 7 weeks of age. However, when compared by chronological age, preterm infants' responses were more variable, with significantly reduced vergence gains, reduced vergence response at 0.33 m, reduced accommodation gain, and increased accommodation at 2 m compared to full-term infants between 8 and 13 weeks after birth. When matched by corrected age, vergence and accommodation in preterm infants show few differences from full-term infants' responses. Maturation appears preprogrammed and is not advanced by visual experience. Longer periods of immature visual responses might leave preterm infants more at risk of development of oculomotor deficits such as strabismus.

  8. Parental accommodation of child anxiety and related symptoms: Range, impact, and correlates

    PubMed Central

    Thompson-Hollands, Johanna; Kerns, Caroline E.; Pincus, Donna B.; Comer, Jonathan S.

    2014-01-01

    Parental accommodation—i.e., changes in parents’ behavior in attempts to prevent or reduce child distress—has been most studied in relation to OCD. Although recent work suggests parents of children with non-OCD anxiety diagnoses also engage in accommodation, little is known about the specific forms, correlates, and associated interference of such accommodation. The present study examined the range and associated interference of parental accommodation behaviors using the newly developed Family Accommodation Checklist and Interference Scale (FACLIS) in a sample of the parents of 71 clinic-referred children with anxiety disorders (NMothers = 68; NFathers= 51). The FACLIS demonstrated good reliability and validity. Ninety-seven percent of mothers and 88% of fathers reported engaging in at least one type of accommodation in the previous two weeks, with parents reporting an average of roughly 4 interfering parental accommodation behaviors. Greater parental accommodation and associated interference were associated with higher maternal distress. Among the anxiety disorders, accommodation was most strongly associated with generalized and separation anxiety disorder, as well as specific phobias. Findings (a) offer psychometric support for the FACLIS as a reliable and valid tool for the assessment of accommodation range and impact, and (b) help clarify the considerable scope and interference associated with parental accommodation of childhood anxiety. PMID:25261837

  9. Evaluating Computer-Based Test Accommodations for English Learners

    ERIC Educational Resources Information Center

    Roohr, Katrina Crotts; Sireci, Stephen G.

    2017-01-01

    Test accommodations for English learners (ELs) are intended to reduce the language barrier and level the playing field, allowing ELs to better demonstrate their true proficiencies. Computer-based accommodations for ELs show promising results for leveling that field while also providing us with additional data to more closely investigate the…

  10. Disability disclosure and workplace accommodations among youth with disabilities.

    PubMed

    Lindsay, Sally; Cagliostro, Elaine; Leck, Joanne; Shen, Winny; Stinson, Jennifer

    2018-03-20

    Many youths with disabilities find it challenging to disclose their medical condition and request workplace accommodations. Our objective was to explore when and how young people with disabilities disclose their condition and request workplace accommodations. We conducted 17 in-depth interviews (11 females, six males) with youth with disabilities aged 15-34 (mean age 26). We analyzed our data using an interpretive, qualitative, and thematic approach. Our results showed the timing of when youth disclosed their disability to their employer depended on disability type and severity, comfort level, type of job, and industry. Youth's strategies and reasons for disclosure included advocating for their needs, being knowledgeable about workplace rights, and accommodation solutions. Facilitators for disclosure included job preparation, self-confidence, and self-advocacy skills, and having an inclusive work environment. Challenges to disability disclosure included the fear of stigma and discrimination, lack of employer's knowledge about disability and accommodations, negative past experiences of disclosing, and not disclosing on your own terms. Our findings highlight that youth encounter several challenges and barriers to disclosing their condition and requesting workplace accommodations. The timing and process for disclosing is complex and further work is needed to help support youth with disclosing their condition. Implications for rehabilitation Clinicians, educators, and employers should emphasize the importance of mentoring and leadership programs to give youth the confidence and self-advocacy skills needed to disclose and ask for accommodations in the workplace. Clinicians should advocate for the inclusion of youth with disabilities in the workforce and educate employers on the importance of doing so. Youth with disabilities need more opportunities for employment training and particularly how to disclose their disability and request workplace accommodations.

  11. Prediction of accommodative optical response in prepresbyopic patients using ultrasound biomicroscopy

    PubMed Central

    Ramasubramanian, Viswanathan; Glasser, Adrian

    2015-01-01

    PURPOSE To determine whether relatively low-resolution ultrasound biomicroscopy (UBM) can predict the accommodative optical response in prepresbyopic eyes as well as in a previous study of young phakic subjects, despite lower accommodative amplitudes. SETTING College of Optometry, University of Houston, Houston, USA. DESIGN Observational cross-sectional study. METHODS Static accommodative optical response was measured with infrared photorefraction and an autorefractor (WR-5100K) in subjects aged 36 to 46 years. A 35 MHz UBM device (Vumax, Sonomed Escalon) was used to image the left eye, while the right eye viewed accommodative stimuli. Custom-developed Matlab image-analysis software was used to perform automated analysis of UBM images to measure the ocular biometry parameters. The accommodative optical response was predicted from biometry parameters using linear regression, 95% confidence intervals (CIs), and 95% prediction intervals. RESULTS The study evaluated 25 subjects. Per-diopter (D) accommodative changes in anterior chamber depth (ACD), lens thickness, anterior and posterior lens radii of curvature, and anterior segment length were similar to previous values from young subjects. The standard deviations (SDs) of accommodative optical response predicted from linear regressions for UBM-measured biometry parameters were ACD, 0.15 D; lens thickness, 0.25 D; anterior lens radii of curvature, 0.09 D; posterior lens radii of curvature, 0.37 D; and anterior segment length, 0.42 D. CONCLUSIONS Ultrasound biomicroscopy parameters can, on average, predict accommodative optical response with SDs of less than 0.55 D using linear regressions and 95% CIs. Ultrasound biomicroscopy can be used to visualize and quantify accommodative biometric changes and predict accommodative optical response in prepresbyopic eyes. PMID:26049831

  12. Static and Dynamic Measurements of Accommodation in Individuals with Down Syndrome

    PubMed Central

    Manny, Ruth E.; Glasser, Adrian; Stuebing, Karla K.

    2011-01-01

    Purpose. To identify whether static and dynamic aspects of accommodation other than accuracy are deficient in individuals with Down syndrome (DS) and whether poor accommodation is related to sensory or motor pathway deficits. Methods. Static aspects of accommodation (maximum accommodative response and lag) were measured with an autorefractor for both proximal and minus lens demands. Dynamic aspects of accommodation (latency, peak velocity, microfluctuations) were recorded at 30 Hz with a custom-built photorefractor as subjects viewed a movie switching between 11 m and 50, 33, 25, or 20 cm. Thirty-six subjects with DS were recruited (age 3 to 39 years), and 24 (67%) had useable responses for at least one study measurement for comparison with 140 controls (3 to 40 years) from a previously published cohort. Results. DS subjects had lower maximum accommodative responses (mean = 2.52 ± 1.66 D) and higher lags (1.81 ± 1.30 D for 33 cm demand) than controls for both proximal and minus lens stimuli. DS subjects had greater microfluctuations (one-way ANCOVA, P < 0.001), and a small percentage of the total number of latency measurements (17% accommodative and 16% disaccommodative) were longer than controls. Peak velocities of accommodation and disaccommodation were not different between groups (one-way ANCOVA, P = 0.143). Conclusions. Peak velocities of accommodation and disaccommodation (primarily motor aspects) did not differ between controls and DS subjects; however, latencies (primarily sensory) and microfluctuations (combined motor and sensory) were poorer in DS subjects. These results suggest that poor accommodative accuracy in individuals with DS may be predominantly related to sensory deficits. PMID:20739471

  13. A Daily Diary Study of Posttraumatic Stress Symptoms and Romantic Partner Accommodation

    PubMed Central

    Campbell, Sarah B.; Renshaw, Keith D.; Kashdan, Todd B.; Curby, Timothy W.; Carter, Sarah P.

    2017-01-01

    Little is known about the role of romantic partner symptom accommodation in PTSD symptom maintenance. To explore the bidirectional associations of posttraumatic stress disorder (PTSD) symptoms and romantic partner symptom accommodation over time, military servicemen (n = 64) with symptoms of PTSD and their co-habiting heterosexual civilian romantic partners (n = 64) completed a 2-week daily diary study. Cross-lagged, autoregressive models assessed the stability of men’s PTSD symptoms and partners’ accommodation, as well as the prospective associations of earlier PTSD symptoms with later accommodation and vice versa. Analyses used Bayesian estimation to provide point estimates (b) and Credible Intervals (CIs). In all models, PTSD symptoms (total and individual clusters) were highly stable (b = 0.91; CI: 0.88–0.95), and accommodation was moderately stable (b = 0.48; CI: 0.40–0.54). In all models, earlier PTSD symptoms (total and clusters) were significantly, positively associated with later accommodation (b = 0.04; CI: 0.02–0.07). In contrast, earlier accommodation was significantly associated only with later situational avoidance (b = 0.02; CI: 0.00–0.07). Thus, PTSD symptoms may lead to subsequent accommodating behaviors in romantic partners, but partner accommodation seems to contribute only to survivors’ future situational avoidance symptoms. The findings reinforce the notion that PTSD symptoms have an impact on relationship behaviors, and that accommodation from partners may sustain avoidant behaviors in particular. Clinicians should attend to romantic partners’ accommodating behaviors when working with survivors. PMID:28270332

  14. Attention-deficit/hyperactivity disorder children exhibit an impaired accommodative response.

    PubMed

    Redondo, Beatriz; Vera, Jesús; Molina, Rubén; García, José Antonio; Ouadi, Miriam; Muñoz-Hoyos, Antonio; Jiménez, Raimundo

    2018-05-01

    Attention-deficit/hyperactivity disorder (ADHD) is one of the most common paediatric neurobehavioural disorders causing multiple functional impairments in children. Based on the relationship between the neural system that controls attention and ocular dynamics, the present study compares the magnitude and variability of accommodation between a group of non-medicated ADHD children and an age-matched control group. The magnitude and variability of the accommodative response were objectively measured in 36 children using the WAM-5500 autorefractometer for 90 consecutive seconds at three static viewing distances (500, 40, and 20 cm). Participants were divided into ADHD (n = 18) or control (n = 18) groups based on clinically validated criteria. Children with ADHD exhibited higher lags of accommodation (p = 0.024), increasing at closer viewing distances, in comparison to the control group. Marginal statistical differences were found for the variability of accommodation (p = 0.066), with the ADHD group showing a trend towards higher variability. Our analysis showed that the magnitude and variability of accommodation did not vary over time between groups (p > 0.05). Our data suggest that children with ADHD have a less accurate accommodative response. These results provide a new ocular index that could help to clarify the relationship between accommodative response and attentional deficits, which could have a direct impact on the academic, cognitive, and visual performance of ADHD children.

  15. Testing Accommodations: Theory and Research to Inform Practice

    ERIC Educational Resources Information Center

    Kettler, Ryan J.

    2012-01-01

    This article presents a framework for practitioners in education and psychology to select accommodations based on student profiles and testing demands. A brief history of testing accommodations policy in the US and a definition of terms provide context for the discussion. A review of theory and empirical findings related to testing accommodations…

  16. Layout of personnel accommodations for the SOFIA

    NASA Astrophysics Data System (ADS)

    Daughters, David M.; Bruich, J. G.; Arceneaux, Gregory P.; Zirretta, Jason; Caton, William B.

    2000-06-01

    The NASA Stratospheric Observatory for Infrared Astronomy (SOFIA) Observatory is based upon a refurbished and heavily modified Boeing 747 SP aircraft. The Observatory, which provides accommodations for the Deutsches Zentrum Fur Luftund Raumfahrt 2.5 m telescope, science investigator teams, scientific instruments, mission crew and support systems. The US contractor team has removed most of the aircraft original furnishings and designed a new Layout of Personnel Accommodations (LOPA) tailored to SOFIA's needs.

  17. Space Station accommodation of attached payloads

    NASA Technical Reports Server (NTRS)

    Browning, Ronald K.; Gervin, Janette C.

    1987-01-01

    The Attached Payload Accommodation Equipment (APAE), which provides the structure to attach payloads to the Space Station truss assembly, to access Space Station resources, and to orient payloads relative to specified targets, is described. The main subelements of the APAE include a station interface adapter, payload interface adapter, subsystem support module, contamination monitoring system, payload pointing system, and attitude determination system. These components can be combined to provide accommodations for small single payloads, small multiple payloads, large self-supported payloads, carrier-mounted payloads, and articulated payloads. The discussion also covers the power, thermal, and data/communications subsystems and operations.

  18. Guidelines for Providing Accommodations Using CASAS Assessment for Learners with Disabilities

    ERIC Educational Resources Information Center

    CASAS - Comprehensive Adult Student Assessment Systems (NJ1), 2005

    2005-01-01

    These guidelines address methods for administering Comprehensive Adult Student Assessment System (CASAS) assessments using accommodations for learners with documented disabilities. The suggested accommodations for disability categories include provisions for: (1) Accommodations in test administration procedures; and (2) Use of appropriate CASAS…

  19. Accommodative performance for chromatic displays.

    PubMed

    Lovasik, J V; Kergoat, H

    1988-01-01

    Over the past few years, video display units (VDUs) have been incorporated into many varieties of workplaces and occupational demands. The success of electro-optical displays in facilitating and improving job performance has spawned interest in extracting further advantage from VDUs by incorporating colour coding into such communication systems. However, concerns have been raised about the effect of chromatic stimuli on the visual comfort and task efficiency, because of the chromatic aberration inherent in the optics of the human eye. In this study, we used a computer aided laser speckle optometer system to measure the accommodative responses to brightness-matched chromatic letters displayed on a high-resolution RGB monitor. Twenty, visually normal, paid volunteers in a 22-35 year age category served as subjects. Stimuli were 14, 21, 28 minutes of arc letters presented in a 'monochromatic' (white, red, green or blue, on a black background) or 'multichromatic' (blue-red, blue-green, red-green, foreground-background combinations) mode at 40 and 80 cm viewing distances. The results demonstrated that while the accommodative responses were strongly influenced by the foreground-background colour combination, the group-averaged dioptric difference across colours was relatively small. Further, accommodative responses were not guided in any systematic fashion by the size of letters presented for fixation. Implications of these findings for display designs are discussed.

  20. The Measures Contribution Researches on Renewable Energy Accommodation Based on Production Simulation

    NASA Astrophysics Data System (ADS)

    Zhe, MI; Jinfang, Zhang; Jun, Liu

    2018-06-01

    This paper presents the impacts of load, source and grid factors on renewable energy accommodation in the northern region of China. Renewable energy curtailment reasons and key measures to improve accommodations are also discussed. The production simulation method is utilized to analysis renewable energy accommodation and the Shapely value method is introduced to calculate the accommodation contribution rate of different factors. The result shows that the amount of renewable energy accommodation is 389 TWh in northern region of China by the year 2020. The contribution rate of load, source and grid factors to renewable energy accommodation are 39%, 35.8% and 25.1%, respectively.

  1. Subjective vs Objective Accommodative Amplitude: Preschool to Presbyopia

    PubMed Central

    Anderson, Heather A.; Stuebing, Karla K.

    2014-01-01

    Purpose This study compared subjective and objective accommodative amplitudes to characterize changes from preschool to presbyopia. Methods Monocular accommodative amplitude was measured with three techniques in random order (subjective push-up, objective minus lens stimulated, and objective proximal stimulated) on 236 subjects 3–64 years using a 1.5mm letter. Subjective push-up amplitudes were the dioptric distance at which the target first blurred along a near-point rod. Objective minus lens stimulated amplitudes were the greatest accommodative response obtained by Grand Seiko autorefraction as subjects viewed the stimulus at 33cm through increasing minus lens powers. Objective proximal stimulated amplitudes were the greatest accommodative response obtained by Grand Seiko autorefraction as subjects viewed the stimulus at increasing proximity from 40cm up to 3.33cm. Results In comparison with subjective push-up amplitudes, objective amplitudes were lower at all ages, with the most dramatic difference occurring in the 3–5 year group (subjective push-up = 16.00 ± 4.98D versus objective proximal stimulated = 7.94 ± 2.37D and objective lens stimulated = 6.20 ± 1.99D). Objective proximal and lens stimulated amplitudes were largest in the 6–10 year group (8.81 ± 1.24D and 8.05 ± 1.82D, respectively) and gradually decreased until the fourth decade of life when a rapid decline to presbyopia occurred. There was a significant linear relationship between objective techniques (y = 0.74 + 0.96x, R2 = 0.85, p<0.001) with greater amplitudes measured for the proximal stimulated technique (mean difference = 0.55D). Conclusions Objective measurements of accommodation demonstrate that accommodative amplitude is substantially less than that measured by the subjective push-up technique, particularly in young children. These findings have important clinical implications for the management of uncorrected hyperopia. PMID:25602235

  2. Caffeine intake is associated with pupil dilation and enhanced accommodation

    PubMed Central

    Abokyi, S; Owusu-Mensah, J; Osei, K A

    2017-01-01

    Purpose It is purported that caffeine, an autonomic stimulant, affects visual performance. This study sought to assess whether caffeine intake was associated with changes in pupil size and/or amplitude of accommodation. Patients and methods A double-masked, crossover study was conducted in 50 healthy subjects of age range 19 to 25 years. Subjects were randomized to treatments such that subjects consumed either 250 mg caffeine drink or vehicle on separate days. Amplitude of accommodation was measured by the push-up technique, and pupil size using a millimeter ruler fixed to a slit lamp biomicroscope in dim illumination (5 lux). Amplitude of accommodation and pupil size were taken at baseline, and at 30, 60 and 90 min time points post treatment. Repeated measures one-way ANOVA and paired t-test were used in analyzing data. Results Amplitude of accommodation and pupil size after caffeine intake were significantly greater than vehicle (P<0.001) at each time point. Consumption of the caffeine beverage was associated with significant increases in amplitude of accommodation and pupil size with time (P<0.001). Amplitude of accommodation rose from 12.4 (±2.2 D) at baseline to 15.8(±2.6 D) at 90 min. Similarly, pupil size increased from 3.4 (±0.4 mm) at baseline to 4.5 (±0.72 mm) at 90 min. Consumption of vehicle was not associated with increase in amplitude of accommodation or pupil size with time. Conclusion Pupil size and accommodation are affected after ingestion of caffeine. This study suggests caffeine may have some influence on visual functions. PMID:27983733

  3. Measuring Changes in Ciliary Muscle Thickness with Accommodation in Young Adults

    PubMed Central

    Lossing, Laura Ashley; Sinnott, Loraine T.; Kao, Chiu-Yen; Richdale, Kathryn; Bailey, Melissa D.

    2012-01-01

    Purpose To develop a measurement protocol for changes in the shape and size of the ciliary muscle with accommodation using the Zeiss Visante™ Anterior Segment Optical Coherence Tomographer (AS-OCT) and to determine the test-retest repeatability of these measurements. Methods Subjects were 25 adults ages 23–28 years. The ciliary muscle was imaged at two visits with the Visante™ while accommodative response was monitored during imaging using the PowerRefractor. Ciliary muscle thickness was measured at 1 mm (CMT1), 2 mm (CMT2), and 3 mm (CMT3) posterior to the scleral spur and at the point of maximal thickness (CMTMAX). Thickness was measured at these locations while subjects viewed a target at distance and at a 4.00-D accommodative stimulus. Outcome measures were the change in thickness between distance and the 4.00-D stimulus and the change in thickness per diopter of accommodative response (PowerRefractor). Finally, the repeatability measurements between visit 1 and visit 2 were determined with a Bland-Altman analysis. Results The statistically significant modeled changes in ciliary muscle thickness were as follows: CMTMAX = 69.2 μm (4.00-D stimulus) and 18.1 μm (per diopter of accommodation); CMT1 = 45.2 μm (4.00-D stimulus) and 12.3 μm (per diopter of accommodation); and CMT3 = −45.9 μm (4.00-D stimulus) and −12.0 μm (per diopter of accommodation); p < 0.0001 for all. Conclusions The combination of the Visante™ and the PowerRefractor is a feasible tool for measuring thickening of ciliary muscle at more anterior locations and thinning at more posterior locations during accommodation. We noted a wide range of accommodative responses during the time of image capture in this study indicating that the most accurate estimates of the change in ciliary muscle dimensions with accommodation may be obtained by using accommodative response rather than stimulus values and by using measurements taken simultaneously with image capture. PMID:22504328

  4. Comparison of the ocular wavefront aberration between pharmacologically-induced and stimulus-driven accommodation.

    PubMed

    Plainis, S; Plevridi, E; Pallikaris, I G

    2009-05-01

    To compare the ocular wavefront aberration between pharmacologically- and stimulus-driven accommodation in phakic eyes of young subjects. The aberration structure of the tested eye when accommodating was measured using the Complete Ophthalmic Analysis System (COAS; AMO WaveFront Sciences, Albuquerque, NM, USA). It was used in conjunction with a purposely-modified Badal optometer to allow blur-driven accommodation to be stimulated by a high contrast letter E with a vergence range between +0.84 D and -8.00 D. Pharmacological accommodation was induced with one drop of pilocarpine 4%. Data from six subjects (age range: 23-36 years) with dark irides were collected. No correlation was found between the maximal levels of accommodative response achieved with an 8 D blur-driven stimulus and pharmacological stimulation. Pharmacological accommodation varied considerably among subjects: maximum accommodation, achieved within 38-85 min following application of pilocarpine, ranged from 2.7 D to 10.0 D. Furthermore, although the changes of spherical aberration and coma as a function of accommodation were indistinguishable between the two methods for low levels of response, a characteristic break in the pattern of aberration occurred at higher levels of pilocarpine-induced accommodation. This probably resulted from differences in the time course of biometric changes occurring with the two methods. Measuring the pilocarpine-induced accommodative response at only one time point after its application may lead to misleading results. The considerable inter-individual differences in the time course of drug-induced accommodative response and its magnitude may lead to overestimation or underestimation of the corresponding amplitude of normal, blur-driven accommodation. Stimulating accommodation by topical application of pilocarpine is inappropriate for evaluating the efficacy of 'accommodating' IOLs.

  5. Topical and intravenous pilocarpine stimulated accommodation in anesthetized rhesus monkeys.

    PubMed

    Wendt, Mark; Glasser, Adrian

    2010-05-01

    Many studies have used pilocarpine to stimulate accommodation in both humans and monkeys. However, the concentrations of pilocarpine used and the methods of administration vary. In this study, three different methods of pilocarpine administration are evaluated for their effectiveness in stimulating accommodation in rhesus monkeys. Experiments were performed in 17 iridectomized, anesthetized rhesus monkeys aged 4-16 years. Maximum accommodation was stimulated in all these monkeys with a 2% pilocarpine solution maintained on the cornea for at least 30 min in a specially designed perfusion lens. In subsequent topical pilocarpine experiments, baseline refraction was measured with a Hartinger coincidence refractometer and then while the monkeys were upright and facing forward, commercially available pilocarpine (2, 4, or 6%) was applied topically to the cornea as 2 or 4 drops in two applications or 6 drops in three applications over a five minute period with the eyelids closed between applications. Alternatively, while supine, 10-12 drops of pilocarpine were maintained on the cornea in a scleral cup for 5 min. Refraction measurements were begun 5 min after the second application of pilocarpine and continued for at least 30 min after initial administration until no further change in refraction occurred. In intravenous experiments, pilocarpine was given either as boluses ranging from 0.1mg/kg to 2mg/kg or boluses followed by a constant infusion at rates between 3.06 mg/kg/h and 11.6 mg/kg/h. Constant 2% pilocarpine solution on the eye in the perfusion lens produced 10.88+/-2.73 D (mean+/-SD) of accommodation. Topically applied pilocarpine produced 3.81 D+/-2.41, 5.49 D+/-4.08, and 5.55 D+/-3.27 using 2%, 4%, and 6% solutions respectively. When expressed as a percentage of the accommodative response amplitude obtained in the same monkey with constant 2% pilocarpine solution on the eye, the responses were 34.7% for 2% pilocarpine, 48.4% for 4% pilocarpine, and 44.6% for 6

  6. Variations in accommodation and convergence responses in a minimally controlled photorefractive setting.

    PubMed

    Horwood, A M; Turner, J E; Houston, S M; Riddell, P M

    2001-11-01

    A remote haploscopic photorefractor, designed for assessment of accommodation and convergence in infants and clinical groups, was used to determine heterophoria accommodative convergence/accommodation (AC/A) ratios in normal naïve adults. These were compared with conventional clinical measures. Twenty-one naïve subjects were used to compare occluded and unoccluded prism cover test responses with the remote haploscopic photorefractor using a text and picture target. Although luminance was generally low for both targets, binocular vergences were appropriate for target demand in both studies. Binocular accommodation showed greater lag for the highest target accommodative demand and the less demanding target. Occlusion not only reduced vergence response, but also frequently caused a marked reduction in accommodation, especially to the picture target. Normal mean AC/A values were found, but with wide variations between individual subjects. Although mean accommodation, vergence, and AC/A values were comparable with published data, we suggest that in these conditions using naïve subjects, accommodation is frequently inaccurate, especially on occlusion, without concomitant loss of vergence, at least at low light levels. Accommodative convergence may play a less important part in, and other cues contribute more to, the near reflex than has been previously suggested.

  7. Accommodation and pupil responses to random-dot stereograms

    PubMed Central

    Suryakumar, Rajaraman; Allison, Robert

    2015-01-01

    We investigated the dynamics of accommodative and pupillary responses to random-dot stereograms presented in crossed and uncrossed disparity in six visually normal young adult subjects (mean age = 25.8 ± 3.1 years). Accommodation and pupil measures were monitored monocularly with a custom built photorefraction system while subjects fixated at the center of a random-dot stereogram. On each trial, the stereogram initially depicted a flat plane and then changed to depict a sinusoidal corrugation in depth while fixation remained constant. Increase in disparity specified depth resulted in pupil constriction during both crossed and uncrossed disparity presentations. The change in pupil size between crossed and uncrossed disparity conditions was not significantly different (p > 0.05). The change in pupil size was also accompanied by a small concomitant increase in accommodation. In addition, the dynamic properties of pupil responses varied as a function of their initial (starting) diameter. The finding that accommodation and pupil responses increased with disparity regardless of the sign of retinal disparity suggests that these responses were driven by apparent depth rather than shifts in mean simulated distance of the stimulus. Presumably the need for the increased depth of focus when viewing stimuli extended in depth results in pupil constriction which also results in a concomitant change in accommodation. Starting position effects in pupil response confirm the non-linearity in the operating range of the pupil. PMID:25891121

  8. New methods for the assessment of accommodative convergence.

    PubMed

    Asakawa, Ken; Ishikawa, Hitoshi; Shoji, Nobuyuki

    2009-01-01

    The authors introduced a new objective method for measuring horizontal eye movements based on the first Purkinje image with the use of infrared charge-coupled device (CCD) cameras and compared stimulus accommodative convergence to accommodation (AC/A) ratios as determined by a standard gradient method. The study included 20 patients, 5 to 9 years old, who had intermittent exotropia (10 eyes) and accommodative esotropia (10 eyes). Measurement of horizontal eye movements in millimeters (mm), based on the first Purkinje image, was obtained with a TriIRIS C9000 instrument (Hamamatsu Photonics K.K., Hamamatsu, Japan). The stimulus AC/A ratio was determined with the far gradient method. The average values of horizontal eye movements (mm) and eye deviation (Delta) (a) before and (b) after an accommodative stimulus of 3.00 diopters (D) were calculated with the following formula: horizontal eye movements (mm/D) and stimulus AC/A ratio (Delta/D) = (b - a)/3. The average values of the horizontal eye movements and the stimulus AC/A ratio were 0.5 mm/D and 3.8 Delta/D, respectively. Correlation analysis showed a strong positive correlation between these two parameters (r = 0.92). Moreover, horizontal eye movements are directly proportional to the AC/A ratio measured with the gradient method. The methods used in this study allow objective recordings of accommodative convergence to be obtained in many clinical situations. Copyright 2009, SLACK Incorporated.

  9. Cultural value orientations, internalized homophobia, and accommodation in romantic relationships.

    PubMed

    Gaines, Stanley O; Henderson, Michael C; Kim, Mary; Gilstrap, Samuel; Yi, Jennifer; Rusbult, Caryl E; Hardin, Deletha P; Gaertner, Lowell

    2005-01-01

    In the present study, we examined the impact of cultural value orientations (i.e., the personally oriented value of individualism, and the socially oriented values of collectivism, familism, romanticism, and spiritualism) on accommodation (i.e., voice and loyalty, rather than exit and neglect, responses to partners' anger or criticism) in heterosexual and gay relationships; and we examined the impact of internalized homophobia (i.e., attitudes toward self, other, and disclosure) on accommodation specifically in gay relationships. A total of 262 heterosexuals (102 men and 162 women) and 857 gays (474 men and 383 women) participated in the present study. Consistent with hypotheses, among heterosexuals and gays, socially oriented values were significantly and positively related to accommodation (whereas the personally oriented value of individualism was unrelated to accommodation); and among gays in particular, internalized homophobia was significantly and negatively related to accommodation. Implications for the study of heterosexual and gay relationships are discussed.

  10. Barriers to Accommodation Use for Students with Disabilities in Postsecondary Education

    ERIC Educational Resources Information Center

    Lyman, Michael James

    2013-01-01

    Students with disabilities at the postsecondary level face a number of different barriers to accommodation use. Past research has shown that students with disabilities that use accommodations obtain greater academic achievement and higher graduation rates. Limited research has been conducted to identify barriers to accommodation use, and the…

  11. Teaching Adolescent Students with Learning Disabilities to Self-Advocate for Accommodations

    ERIC Educational Resources Information Center

    Prater, Mary Anne; Redman, Ashleigh Smith; Anderson, Darlene; Gibb, Gordon S.

    2014-01-01

    In the general education classroom students with learning disabilities (LD) often need academic accommodations to be successful. These accommodations are typically selected and implemented by their general education teachers, not by the students themselves. High school students with LD were taught to recognize when an accommodation was needed,…

  12. Accommodation of Symptoms in Anorexia Nervosa: A Qualitative Study.

    PubMed

    Fox, John R E; Whittlesea, Anna

    2017-03-01

    Anorexia nervosa (AN) continues to remain poorly understood within eating disorders. Recent research and theory have moved away from understanding its aetiological causes, addressing instead potential maintaining factors. This study is focused on interpersonal maintenance factors: the response of close others. Relatives of those with AN typically carry the main burden of care, and research has found high levels of carer distress and unmet needs. Recent theories have proposed this emotional impact to contribute to expressed emotion and other unhelpful caregiver interactions which inadvertently maintain AN. One such understudied response is accommodation, described as a 'process' whereby caregivers 'assist or participate' in symptomatic behaviours of the cared for individual. There is a dearth of research relating to accommodation within eating disorders, particularly qualitative accounts. This study utilized a grounded theory methodology to explore caregivers' responses to managing AN, focusing particularly on carers' experience of accommodation. Eight participants with experience of caring for an individual diagnosed with AN were interviewed. Participants were recruited from a national eating disorder charity and regional eating disorder service. A number of themes emerged, including the importance of caregivers' emotional resources in mediating accommodation responses. Low-perceived efficacy over AN contributed to caregiver burnout. Decreased emotional resources influenced a shift in caregiving aims conducive with accommodation. Nevertheless, carers perceived accommodation as counterproductive to recovery and consequently experienced internal conflict (cognitive dissonance). Dissonance was reduced using a number of cognitive and behavioural strategies. The implications of these findings are discussed with reference to existing literature. Copyright © 2016 John Wiley & Sons, Ltd. Anorexia nervosa (AN) can be difficult to manage. Over time, carers can feel

  13. Family accommodation in obsessive-compulsive and anxiety disorders: a five-year update

    PubMed Central

    Lebowitz, Eli R.; Panza, Kaitlyn E.; Bloch, Michael H.

    2016-01-01

    Family accommodation describes changes that individuals make to their behavior, to help their relative who is dealing with a psychiatric and/or psychological disorder(s), avoid or alleviate distress related to the disorder. Research on family accommodation has advanced rapidly. In this update we aim to provide a synthesis of findings from the past five years. A search of available, peer-reviewed, English language papers was conducted through PubMed and PsycINFO, cross referencing psychiatric disorders with accommodation and other family-related terms. The resulting 121 papers were individually reviewed and evaluated and the main findings were discussed. Family accommodation is common in obsessive-compulsive disorder (OCD) and in anxiety disorders, and manifests similarly across these disorders. Family accommodation is associated with more severe psychopathology and poorer clinical outcomes. Treatments have begun to focus on the reduction of family accommodation as a primary therapeutic goal and finally, neurobiological underpinnings of family accommodation are beginning to be investigated. PMID:26613396

  14. Family accommodation in obsessive-compulsive and anxiety disorders: a five-year update.

    PubMed

    Lebowitz, Eli R; Panza, Kaitlyn E; Bloch, Michael H

    2016-01-01

    Family accommodation describes changes that individuals make to their behavior, to help their relative who is dealing with a psychiatric and/or psychological disorder(s), avoid or alleviate distress related to the disorder. Research on family accommodation has advanced rapidly. In this update we aim to provide a synthesis of findings from the past five years. A search of available, peer-reviewed, English language papers was conducted through PubMed and PsycINFO, cross referencing psychiatric disorders with accommodation and other family-related terms. The resulting 121 papers were individually reviewed and evaluated and the main findings were discussed. Family accommodation is common in obsessive-compulsive disorder (OCD) and in anxiety disorders, and manifests similarly across these disorders. Family accommodation is associated with more severe psychopathology and poorer clinical outcomes. Treatments have begun to focus on the reduction of family accommodation as a primary therapeutic goal and finally, neurobiological underpinnings of family accommodation are beginning to be investigated.

  15. Amplitude, Latency, and Peak Velocity in Accommodation and Disaccommodation Dynamics

    PubMed Central

    Papadatou, Eleni; Ferrer-Blasco, Teresa; Montés-Micó, Robert

    2017-01-01

    The aim of this work was to ascertain whether there are differences in amplitude, latency, and peak velocity of accommodation and disaccommodation responses when different analysis strategies are used to compute them, such as fitting different functions to the responses or for smoothing them prior to computing the parameters. Accommodation and disaccommodation responses from four subjects to pulse changes in demand were recorded by means of aberrometry. Three different strategies were followed to analyze such responses: fitting an exponential function to the experimental data; fitting a Boltzmann sigmoid function to the data; and smoothing the data. Amplitude, latency, and peak velocity of the responses were extracted. Significant differences were found between the peak velocity in accommodation computed by fitting an exponential function and smoothing the experimental data (mean difference 2.36 D/s). Regarding disaccommodation, significant differences were found between latency and peak velocity, calculated with the two same strategies (mean difference of 0.15 s and −3.56 D/s, resp.). The strategy used to analyze accommodation and disaccommodation responses seems to affect the parameters that describe accommodation and disaccommodation dynamics. These results highlight the importance of choosing the most adequate analysis strategy in each individual to obtain the parameters that characterize accommodation and disaccommodation dynamics. PMID:29226128

  16. Hyperelastic modelling of the crystalline lens: Accommodation and presbyopia

    PubMed Central

    Lanchares, Elena; Navarro, Rafael; Calvo, Begoña

    2012-01-01

    Purpose The modification of the mechanical properties of the human crystalline lens with age can be a major cause of presbyopia. Since these properties cannot be measured in vivo, numerical simulation can be used to estimate them. We propose an inverse method to determine age-dependent change in the material properties of the tissues composing the human crystalline lens. Methods A finite element model of a 30-year-old lens in the accommodated state was developed. The force necessary to achieve full accommodation in a 30-year-old lens of known external geometry was computed using this model. Two additional numerical models of the lens corresponding to the ages of 40 and 50 years were then built. Assuming that the accommodative force applied to the lens remains constant with age, the material properties of nucleus and cortex were estimated by inverse analysis. Results The zonular force necessary to reshape the model of a 30-year-old lens from the accommodated to the unaccommodated geometry was 0.078 newton (N). Both nucleus and cortex became stiffer with age. The stiffness of the nucleus increased with age at a higher rate than the cortex. Conclusions In agreement with the classical theory of Helmholtz, on which we based our model, our results indicate that a major cause of presbyopia is that both nucleus and cortex become stiffer with age; therefore, a constant value of the zonular forces with aging does not achieve full accommodation, that is, the accommodation capability decreases.

  17. Family accommodation mediates the association between anxiety symptoms in mothers and children.

    PubMed

    Jones, Johnna D; Lebowitz, Eli R; Marin, Carla E; Stark, Kevin D

    2015-01-01

    The link between child anxiety and maternal anxiety has been well established but the factors underlying this association are not well understood. One potential factor is family accommodation, which describes ways in which parents change their behaviour to help a child avoid or alleviate anxiety. Family accommodation has been associated with greater symptom severity, more impairment and poorer treatment outcomes in the child. The aim of this study was to investigate whether maternal accommodation mediates the relation between parent and child anxiety. Mothers of children (N = 85) aged 7-17 years (M = 11.79) completed measures of their own anxiety (State-Trait Anxiety Inventory (STAI)), their child's anxiety (Screen for Child Anxiety Related Disorders (SCARED)), and family accommodation (Family Accommodation Scale Anxiety (FASA)). Structural equation modelling (SEM) was used to test the mediational role of accommodation linking parent and child anxiety. Family accommodation was found to significantly mediate the link between maternal anxiety and child anxiety. These results inform theory and imply that the development of interventions designed to target family accommodation may improve the prognosis of those diagnosed with paediatric anxiety disorders and youth with subclinical anxiety symptoms by reducing both parent and child anxiety.

  18. 14 CFR 1204.1510 - Efforts to accommodate intergovernmental concerns.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Efforts to accommodate intergovernmental concerns. 1204.1510 Section 1204.1510 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... Programs and Activities § 1204.1510 Efforts to accommodate intergovernmental concerns. (a) If a state...

  19. Circadian rhythms of visual accommodation responses and physiological correlations.

    NASA Technical Reports Server (NTRS)

    Murphy, M. R.; Randle, R. J.; Williams, B. A.

    1972-01-01

    Use of a recently developed servocontrolled infrared optometer to continuously record the state of monocular focus while subjects viewed a visual target for which the stimulus to focus was systematically varied. Calculated parameters form recorded data - e.g., speeds of accommodation to approaching and receding targets, magnitude of accommodation to step changes in target distance, and amplitude and phase lag of response to sinusoidally varying stimuli were submitted to periodicity analyses. Ear canal temperature (ECT) and heart rate (HR) rhythms were also recorded for physiological correlation with accommodation rhythms. HR demonstrated a 24-hr rhythm, but ECT data did not.

  20. Effect of third-order aberrations on dynamic accommodation.

    PubMed

    López-Gil, Norberto; Rucker, Frances J; Stark, Lawrence R; Badar, Mustanser; Borgovan, Theodore; Burke, Sean; Kruger, Philip B

    2007-03-01

    We investigate the potential for the third-order aberrations coma and trefoil to provide a signed cue to accommodation. It is first demonstrated theoretically (with some assumptions) that the point spread function is insensitive to the sign of spherical defocus in the presence of odd-order aberrations. In an experimental investigation, the accommodation response to a sinusoidal change in vergence (1-3D, 0.2Hz) of a monochromatic stimulus was obtained with a dynamic infrared optometer. Measurements were obtained in 10 young visually normal individuals with and without custom contact lenses that induced low and high values of r.m.s. trefoil (0.25, 1.03 microm) and coma (0.34, 0.94 microm). Despite variation between subjects, we did not find any statistically significant increase or decrease in the accommodative gain for low levels of trefoil and coma, although effects approached or reached significance for the high levels of trefoil and coma. Theoretical and experimental results indicate that the presence of Zernike third-order aberrations on the eye does not seem to play a crucial role in the dynamics of the accommodation response.

  1. Aerobrake assembly with minimum Space Station accommodation

    NASA Technical Reports Server (NTRS)

    Katzberg, Steven J.; Butler, David H.; Doggett, William R.; Russell, James W.; Hurban, Theresa

    1991-01-01

    The minimum Space Station Freedom accommodations required for initial assembly, repair, and refurbishment of the Lunar aerobrake were investigated. Baseline Space Station Freedom support services were assumed, as well as reasonable earth-to-orbit possibilities. A set of three aerobrake configurations representative of the major themes in aerobraking were developed. Structural assembly concepts, along with on-orbit assembly and refurbishment scenarios were created. The scenarios were exercised to identify required Space Station Freedom accommodations. Finally, important areas for follow-on study were also identified.

  2. Frequency of convergence and accommodative disorders in a clinical population of Mashhad, Iran.

    PubMed

    Hoseini-Yazdi, Seyed Hosein; Yekta, AbbasAli; Nouri, Hosein; Heravian, Javad; Ostadimoghaddam, Hadi; Khabazkhoob, Mehdi

    2015-01-01

    To investigate the frequency of convergence and accommodation anomalies in an optometric clinical setting in Mashhad, Iran, and to determine tests with highest accuracy in diagnosing these anomalies. From 261 patients who came to the optometric clinics of Mashhad University of Medical Sciences during a month, 83 of them were included in the study based on the inclusion criteria. Near point of convergence (NPC), near and distance heterophoria, monocular and binocular accommodative facility (MAF and BAF, respectively), lag of accommodation, positive and negative fusional vergences (PFV and NFV, respectively), AC/A ratio, relative accommodation, and amplitude of accommodation (AA) were measured to diagnose the convergence and accommodation anomalies. The results were also compared between symptomatic and asymptomatic patients. The accuracy of these tests was explored using sensitivity (S), specificity (Sp), and positive and negative likelihood ratios (LR+, LR-). Mean age of the patients was 21.3 ± 3.5 years and 14.5% of them had specific binocular and accommodative symptoms. Convergence and accommodative anomalies were found in 19.3% of the patients; accommodative excess (4.8%) and convergence insufficiency (3.6%) were the most common accommodative and convergence disorders, respectively. Symptomatic patients showed lower values for BAF (p = .003), MAF (p = .001), as well as AA (p = .001) compared with asymptomatic patients. Moreover, BAF (S = 75%, Sp = 62%) and MAF (S = 62%, Sp = 89%) were the most accurate tests for detecting accommodative and convergence disorders in terms of both sensitivity and specificity. Convergence and accommodative anomalies are the most common binocular disorders in optometric patients. Including tests of monocular and binocular accommodative facility in routine eye examinations as accurate tests to diagnose these anomalies requires further investigation.

  3. Accommodation in Untextured Stimulus Fields.

    DTIC Science & Technology

    1979-05-01

    that accommodation is notably inaccurate with reduced illumination, textural cue removal, or small aper ture viewing. These situational ametropias are...dark focus. Although, for any individual, large correlations exist among these ametropias , statistically reliable differen ces occur among them as well

  4. Success in baccalaureate nursing programs: a matter of accommodation?

    PubMed

    Haislett, J; Hughes, R B; Atkinson, G; Williams, C L

    1993-02-01

    This article explores student learning styles as an important variable in four-year baccalaureate nursing programs. Student learning styles were assessed by Kolb's Learning Style Inventory-1985 (LSI-1985), which identifies the accommodator, diverger, assimilator, and converger learning styles. The authors examined the relationship between learning style and academic performance as measured by grade-point ratio (GPR) and studied behaviors and attitudes as measured by Brown and Holtzman's (1964) Survey of Study Habits and Attitudes. Analysis indicated that this sample (N = 100) included mainly assimilators and divergers, making reflective observation the most common mode of learning. Compared to the accommodator/converger group, the assimilator/diverger group earned a significantly higher GPR, significantly better scores on the study habits variable of Work Methods (WM), and moderately better scores on the study attitude variable of Educational Acceptance (EA). Accommodators were identified as the most at-risk learning style group, and specific interventions were suggested to assist accommodators in adapting to the academic rigors of a nursing curriculum.

  5. Accommodating Presuppositions Is Inappropriate in Implausible Contexts.

    PubMed

    Singh, Raj; Fedorenko, Evelina; Mahowald, Kyle; Gibson, Edward

    2016-04-01

    According to one view of linguistic information (Karttunen, 1974; Stalnaker, 1974), a speaker can convey contextually new information in one of two ways: (a) by asserting the content as new information; or (b) by presupposing the content as given information which would then have to be accommodated. This distinction predicts that it is conversationally more appropriate to assert implausible information rather than presuppose it (e.g., von Fintel, 2008; Heim, 1992; Stalnaker, 2002). A second view rejects the assumption that presuppositions are accommodated; instead, presuppositions are assimilated into asserted content and both are correspondingly open to challenge (e.g., Gazdar, 1979; van der Sandt, 1992). Under this view, we should not expect to find a difference in conversational appropriateness between asserting implausible information and presupposing it. To distinguish between these two views of linguistic information, we performed two self-paced reading experiments with an on-line stops-making-sense judgment. The results of the two experiments-using the presupposition triggers the and too-show that accommodation is inappropriate (makes less sense) relative to non-presuppositional controls when the presupposed information is implausible but not when it is plausible. These results provide support for the first view of linguistic information: the contrast in implausible contexts can only be explained if there is a presupposition-assertion distinction and accommodation is a mechanism dedicated to reasoning about presuppositions. Copyright © 2015 Cognitive Science Society, Inc.

  6. Extralenticular and lenticular aspects of accommodation and presbyopia in human versus monkey eyes.

    PubMed

    Croft, Mary Ann; McDonald, Jared P; Katz, Alexander; Lin, Ting-Li; Lütjen-Drecoll, Elke; Kaufman, Paul L

    2013-07-26

    To determine if the accommodative forward movements of the vitreous zonule and lens equator occur in the human eye, as they do in the rhesus monkey eye; to investigate the connection between the vitreous zonule posterior insertion zone and the posterior lens equator; and to determine which components-muscle apex width, lens thickness, lens equator position, vitreous zonule, circumlental space, and/or other intraocular dimensions, including those stated in the objectives above-are most important in predicting accommodative amplitude and presbyopia. Accommodation was induced pharmacologically in 12 visually normal human subjects (ages 19-65 years) and by midbrain electrical stimulation in 11 rhesus monkeys (ages 6-27 years). Ultrasound biomicroscopy imaged the entire ciliary body, anterior and posterior lens surfaces, and the zonule. Relevant distances were measured in the resting and accommodated eyes. Stepwise regression analysis determined which variables were the most important predictors. The human vitreous zonule and lens equator move forward (anteriorly) during accommodation, and their movements decline with age, as in the monkey. Over all ages studied, age could explain accommodative amplitude, but not as well as accommodative lens thickening and resting muscle apex thickness did together. Accommodative change in distances between the vitreous zonule insertion zone and the posterior lens equator or muscle apex were important for predicting accommodative lens thickening. Our findings quantify the movements of the zonule and ciliary muscle during accommodation, and identify their age-related changes that could impact the optical change that occurs during accommodation and IOL function.

  7. Disabilities in the workplace: recruitment, accommodation, and retention.

    PubMed

    Davis, Linda

    2005-07-01

    Who has never had a need for accommodation to perform a job because of age-related changes, gender issues related to family care, religious practices, health status, or disability? Who has never had the benefit of universal accommodations designed to provide access for individuals with disabilities, such as using the handicap button to open a door when one's arms are loaded? All of society has had the benefit of inclusion of individuals with disabilities within the work force. Occupational health nurses are essential to accommodating new employees with disabilities, assisting ill or injured employees in returning to work, and changing attitudes toward disabled workers. Additionally, nurses have the skills and knowledge for leading and managing newly emerging disease management programs for workers with disabilities caused by chronic illness.

  8. Design Principles to Accommodate Older Adults

    PubMed Central

    Farage, Miranda A.; Miller, Kenneth W.; Ajayi, Funmi; Hutchins, Deborah

    2012-01-01

    The global population is aging. In many industrial countries, almost one in five people are over age 65. As people age, gradual changes ensue in vision, hearing, balance, coordination, and memory. Products, communication materials, and the physical environment must be thoughtfully designed to meet the needs of people of all ages. This article summarizes normal changes in sensory function, mobility, balance, memory, and attention that occur with age. It presents practical guidelines that allow design professionals to accommodate these changes and better meet the needs of older adults. Designing for older adults is inclusive design: it accommodates a range of physical and cognitive abilities and promotes simplicity, flexibility, and ease of use for people of any age. PMID:22980147

  9. Design principles to accommodate older adults.

    PubMed

    Farage, Miranda A; Miller, Kenneth W; Ajayi, Funmi; Hutchins, Deborah

    2012-02-29

    The global population is aging. In many industrial countries, almost one in five people are over age 65. As people age, gradual changes ensue in vision, hearing, balance, coordination, and memory. Products, communication materials, and the physical environment must be thoughtfully designed to meet the needs of people of all ages. This article summarizes normal changes in sensory function, mobility, balance, memory, and attention that occur with age. It presents practical guidelines that allow design professionals to accommodate these changes and better meet the needs of older adults. Designing for older adults is inclusive design: it accommodates a range of physical and cognitive abilities and promotes simplicity, flexibility, and ease of use for people of any age.

  10. Intraocular Pressure Changes during Accommodation in Progressing Myopes, Stable Myopes and Emmetropes

    PubMed Central

    Jiang, Xiaodan; Hu, Xiaodan; Zhang, Mingzhou; Li, Xuemin

    2015-01-01

    Purpose To investigate the changes of intraocular pressure (IOP) induced by 3-diopter (3 D) accommodation in progressing myopes, stable myopes and emmetropes. Design Cross-sectional study. Participants 318 subjects including 270 myopes and 48 emmetropes. Methods 195 progressing myopes, 75 stable myopes and 48 emmetropes participated in this study. All subjects had their IOP measured using iCare rebound tonometer while accommodative stimuli of 0 D and 3 D were presented. Main Outcome Measures IOP values without accommodation and with 3 D accommodation were measured in all subjects. Baseline IOPs and IOP changes were compared within and between groups. Results There was no significant difference in IOPs between progressing myopes, stable myopes and emmetropes when no accommodation was induced (17.47±3.46, 16.62±2.98 and 16.80±3.62 respectively, p>0.05). IOP experienced an insignificantly slight decrease after 3 D accommodation in three groups (mean change -0.19±2.16, -0.03±1.68 and -0.39±2.65 respectively, p>0.05). Subgroup analysis showed in progressing myopic group, IOP of children (<18 years old) declined with accommodation while IOP of adults (≥18 years) increased, and the difference was statistically significant (p = 0.008). However, after excluding the age factor, accommodation induced IOP changes of high progressing myopes (≤-6 D), low, moderate and non-myopes (>-6 D) was not significantly different after Bonferroni correction (p = 0.838). Conclusions Although no difference was detected between the baseline IOPs and accommodation induced IOP changes in progressing myopes, stable myopes and emmetropes, this study found accommodation could cause transient IOP elevation in adult progressing myopes. PMID:26517725

  11. Utility accommodation and conflict tracker (UACT) installation and configuration manual.

    DOT National Transportation Integrated Search

    2009-02-01

    Project 0-5475 performed a comprehensive analysis of utility conflict data/information flows between utility : accommodation stakeholders in the Texas Department of Transportation project development process, : developed data models to accommodate wo...

  12. 46 CFR 127.270 - Location of accommodations and pilothouse.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Section 127.270 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS... waterline. (d) No hawse pipe or chain pipe may pass through accommodations for crew members or offshore... accommodations and chain lockers, cargo spaces, or machinery spaces. (f) No sounding tubes, or vents from fuel...

  13. 46 CFR 127.270 - Location of accommodations and pilothouse.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Section 127.270 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS... waterline. (d) No hawse pipe or chain pipe may pass through accommodations for crew members or offshore... accommodations and chain lockers, cargo spaces, or machinery spaces. (f) No sounding tubes, or vents from fuel...

  14. 46 CFR 127.270 - Location of accommodations and pilothouse.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Section 127.270 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS... waterline. (d) No hawse pipe or chain pipe may pass through accommodations for crew members or offshore... accommodations and chain lockers, cargo spaces, or machinery spaces. (f) No sounding tubes, or vents from fuel...

  15. Testing the Contingency Theory of Accommodation in Public Relations.

    ERIC Educational Resources Information Center

    Cancel, Amanda E.; Mitrook, Michael A.; Cameron, Glen T.

    1999-01-01

    Interviews 18 public-relations professionals to provide grounding and refinement of the contingency theory of accommodation in public relations. Supports a continuum from pure accommodation to pure advocacy and a matrix of variables affecting the continuum. Concludes that the practitioners' view of their communication world offers validity to the…

  16. 46 CFR 127.270 - Location of accommodations and pilothouse.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Section 127.270 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS... waterline. (d) No hawse pipe or chain pipe may pass through accommodations for crew members or offshore... accommodations and chain lockers, cargo spaces, or machinery spaces. (f) No sounding tubes, or vents from fuel...

  17. 46 CFR 127.270 - Location of accommodations and pilothouse.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Section 127.270 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS... waterline. (d) No hawse pipe or chain pipe may pass through accommodations for crew members or offshore... accommodations and chain lockers, cargo spaces, or machinery spaces. (f) No sounding tubes, or vents from fuel...

  18. Relationship of ocular accommodation and motor skills performance in developmental coordination disorder.

    PubMed

    Rafique, Sara A; Northway, Nadia

    2015-08-01

    Ocular accommodation provides a well-focussed image, feedback for accurate eye movement control, and cues for depth perception. To accurately perform visually guided motor tasks, integration of ocular motor systems is essential. Children with motor coordination impairment are established to be at higher risk of accommodation anomalies. The aim of the present study was to examine the relationship between ocular accommodation and motor tasks, which are often overlooked, in order to better understand the problems experienced by children with motor coordination impairment. Visual function, gross and fine motor skills were assessed in children with developmental coordination disorder (DCD) and typically developing control children. Children with DCD had significantly poorer accommodation facility and amplitude dynamics compared to controls. Results indicate a relationship between impaired accommodation and motor skills. Specifically, accommodation anomalies correlated with visual motor, upper limb and fine dexterity task performance. Consequently, we argue accommodation anomalies influence the ineffective coordination of action and perception in DCD. Furthermore, reading disabilities were related to poorer motor performance. We postulate the role of the fastigial nucleus as a common pathway for accommodation and motor deficits. Implications of the findings and recommended visual screening protocols are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. The effects of a convex rear-view mirror on ocular accommodative responses.

    PubMed

    Nagata, Tatsuo; Iwasaki, Tsuneto; Kondo, Hiroyuki; Tawara, Akihiko

    2013-11-01

    Convex mirrors are universally used as rear-view mirrors in automobiles. However, the ocular accommodative responses during the use of these mirrors have not yet been examined. This study investigated the effects of a convex mirror on the ocular accommodative systems. Seven young adults with normal visual functions were ordered to binocularly watch an object in a convex or plane mirror. The accommodative responses were measured with an infrared optometer. The average of the accommodation of all subjects while viewing the object in the convex mirror were significantly nearer than in the plane mirror, although all subjects perceived the position of the object in the convex mirror as being farther away. Moreover, the fluctuations of accommodation were significantly larger for the convex mirror. The convex mirror caused the 'false recognition of distance', which induced the large accommodative fluctuations and blurred vision. Manufactures should consider the ocular accommodative responses as a new indicator for increasing automotive safety. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  20. Full-Field Accommodation in Rhesus Monkeys Measured Using Infrared Photorefraction

    PubMed Central

    He, Lin; Wendt, Mark

    2012-01-01

    Purpose. Full-field photorefraction was measured during accommodation in anesthetized monkeys to better understand the monkey as a model of human accommodation and how accommodation affects off-axis refraction. Methods. A photorefraction camera was rotated on a 30-cm-long rod in a horizontal arc, with the eye at the center of curvature of the arc so that the measurement distance remained constant. The resistance of a potentiometer attached to the rotation center of the rod changed proportionally with the rotation angle. Photorefraction and rotation angle were simultaneously measured at 30 Hz. Trial-lens calibrations were performed on-axis and across the full field in each eye. Full-field refraction measurements were compared using on-axis and full-field calibrations. In five iridectomized monkeys (mean age in years ± SD: 12.8 ± 0.9), full-field refraction was measured before and during carbachol iontophoresis stimulated accommodation, a total of seven times (with one repeat each in two monkeys). Results. Measurements over approximately 20 seconds had <0.1 D of variance and an angular resolution of 0.1°, from at least −30° to 30°. Photorefraction calibrations performed over the full field had a maximum variation in the calibration slopes within one eye of 90%. Applying full-field calibrations versus on-axis calibrations resulted in a decrease in the maximum SDs of the calculated refractions from 1.99 to 0.89 D for relative peripheral refractive error and from 4.68 to 1.99 D for relative accommodation. Conclusions. By applying full-field calibrations, relative accommodation in pharmacologically stimulated monkeys was found to be similar to that reported with voluntary accommodation in humans. PMID:22125278

  1. Accommodating Elementary Students' Learning Styles.

    ERIC Educational Resources Information Center

    Wallace, James

    1995-01-01

    Examines the perceptual learning style preferences of sixth- and seventh-grade students in the Philippines. Finds that the visual modality was the most preferred and the auditory modality was the least preferred. Offers suggestions for accommodating visual, tactile, and kinesthetic preferences. (RS)

  2. Cultural Accommodation Model of Counseling

    ERIC Educational Resources Information Center

    Leong, Frederick T. L.

    2011-01-01

    The current article provides an overview to the cultural accommodation model (CAM) of counseling (Leong & Lee, 2006) that may help guide employment counselors' work. The integrative multidimensional model of cross-cultural counseling (Leong, 1996), a precursor to the CAM, is also reviewed.

  3. An Analysis of State Assessment Policies Addressing the Accommodation of English Language Learners

    ERIC Educational Resources Information Center

    Rivera, Carlene; Collum, Eric

    2004-01-01

    This paper reviews 15 research studies that: (1) examined effects of particular accommodations or groups of accommodations on performance: and (2) employed experimental and quasi-experimental research designs that allowed examination of the effect of the accommodation(s) on English Language Learners (ELLs) and non-ELLs. Studies looked at one or…

  4. Frequency-Accommodating Manchester Decoder

    NASA Technical Reports Server (NTRS)

    Vasquez, Mario J.

    1988-01-01

    No adjustment necessary to cover a 10:1 frequency range. Decoding circuit converts biphase-level pulse-code modulation to nonreturn-to-zero (NRZ)-level pulse-code modulation plus clock signal. Circuit accommodates input data rate of 50 to 500 kb/s. Tracks gradual changes in rate automatically, eliminating need for extra circuits and manual switching to adjust to different rates.

  5. Accommodation and convergence during sustained computer work.

    PubMed

    Collier, Juanita D; Rosenfield, Mark

    2011-07-01

    With computer usage becoming almost universal in contemporary society, the reported prevalence of computer vision syndrome (CVS) is extremely high. However, the precise physiological mechanisms underlying CVS remain unclear. Although abnormal accommodation and vergence responses have been cited as being responsible for the symptoms produced, there is little objective evidence to support this claim. Accordingly, this study measured both of these oculomotor parameters during a sustained period of computer use. Subjects (N = 20) were required to read text aloud from a laptop computer at a viewing distance of 50 cm for a sustained 30-minute period through their habitual refractive correction. At 2-minute intervals, the accommodative response (AR) to the computer screen was measured objectively using a Grand Seiko WAM 5500 optometer (Grand Seiko, Hiroshima, Japan). Additionally, the vergence response was assessed by measuring the associated phoria (AP), i.e., prism to eliminate fixation disparity, using a customized fixation disparity target that appeared on the computer screen. Subjects were asked to rate the degree of difficulty of the reading task on a scale from 1 to 10. Mean accommodation and AP values during the task were 1.07 diopters and 0.74∆ base-in (BI), respectively. The mean discomfort score was 4.9. No significant changes in accommodation or vergence were observed during the course of the 30-minute test period. There was no significant difference in the AR as a function of subjective difficulty. However, the mean AP for the subjects who reported the least and greatest discomfort during the task was 1.55∆ BI and 0, respectively (P = 0.02). CVS, after 30 minutes was worse in subjects exhibiting zero fixation disparity when compared with those subjects having a BI AP but does not appear to be related to differences in accommodation. A slightly reduced vergence response increases subject comfort during the task. Copyright © 2011 American Optometric

  6. [Effects of visual optical stimuli for accommodation-convergence system on asthenopia].

    PubMed

    Iwasaki, Tsuneto; Tawara, Akihiko; Miyake, Nobuyuki

    2006-01-01

    We investigated the effect on eyestrain of optical stimuli that we designed for accommodation and convergence systems. Eight female students were given optical stimuli for accommodation and convergence systems for 1.5 min immediately after 20 min of a sustained task on a 3-D display. Before and after the trial, their ocular functions were measured and their symptoms were assessed. The optical stimuli were applied by moving targets of scenery images far and near around the far point position of both eyes on a horizonal place, which induced divergence in the direction of the eye position of rest. In a control group, subjects rested with closed eyes for 1.5 min instead of applying the optical stimuli. There were significant changes in the accommodative contraction time (from far to near) and the accommodative relaxation time (from near to far) and the lag of accommodation at near target, from 1.26 s to 1.62 s and from 1.49 s to 1.63 s and from 0.5 D to 0.65 D, respectively, and in the symptoms in the control group after the duration of closed-eye rest. In the stimulus group, however, the changes of those functions were smaller than in the control group. From these results, we suggest that our designed optical stimuli for accommodation and convergence systems are effective on asthenopia following accommodative dysfunction.

  7. Magnifications of Single and Dual Element Accommodative Intraocular Lenses: Paraxial Optics Analysis

    PubMed Central

    Ale, Jit B; Manns, Fabrice; Ho, Arthur

    2010-01-01

    Purpose Using an analytical approach of paraxial optics, we evaluated the magnification of a model eye implanted with single-element (1E) and dual-element (2E) translating-optics accommodative intraocular lenses (AIOL) with an objective of understanding key control parameters relevant to their design. Potential clinical implications of the results arising from pseudophakic accommodation were also considered. Methods Lateral and angular magnifications in a pseudophakic model eye were analyzed using the matrix method of paraxial optics. The effects of key control parameters such as direction (forward or backward) and distance (0 to 2 mm) of translation, power combinations of the 2E-AIOL elements (front element power range +20.0 D to +40.0 D), and amplitudes of accommodation (0 to 4 D) were tested. Relative magnification, defined as the ratio of the retinal image size of the accommodated eye to that of unaccommodated phakic (rLM1) or pseudophakic (rLM2) model eyes, was computed to determine how retinal image size changes with pseudophakic accommodation. Results Both lateral and angular magnifications increased with increased power of the front element in 2E-AIOL and amplitude of accommodation. For a 2E-AIOL with front element power of +35 D, rLM1 and rLM2 increased by 17.0% and 16.3%, respectively, per millimetre of forward translation of the element, compared to the magnification at distance focus (unaccommodated). These changes correspond to a change of 9.4% and 6.5% per dioptre of accommodation, respectively. Angular magnification also increased with pseudophakic accommodation. 1E-AIOLs produced consistently less magnification than 2E-AIOLs. Relative retinal image size decreased at a rate of 0.25% with each dioptre of accommodation in the phakic model eye. The position of the image space nodal point shifted away from the retina (towards the cornea) with both phakic and pseudophakic accommodation. Conclusion Power of the mobile element, and amount and direction of

  8. Extralenticular and Lenticular Aspects of Accommodation and Presbyopia in Human Versus Monkey Eyes

    PubMed Central

    Croft, Mary Ann; McDonald, Jared P.; Katz, Alexander; Lin, Ting-Li; Lütjen-Drecoll, Elke; Kaufman, Paul L.

    2013-01-01

    Purpose. To determine if the accommodative forward movements of the vitreous zonule and lens equator occur in the human eye, as they do in the rhesus monkey eye; to investigate the connection between the vitreous zonule posterior insertion zone and the posterior lens equator; and to determine which components—muscle apex width, lens thickness, lens equator position, vitreous zonule, circumlental space, and/or other intraocular dimensions, including those stated in the objectives above—are most important in predicting accommodative amplitude and presbyopia. Methods. Accommodation was induced pharmacologically in 12 visually normal human subjects (ages 19–65 years) and by midbrain electrical stimulation in 11 rhesus monkeys (ages 6–27 years). Ultrasound biomicroscopy imaged the entire ciliary body, anterior and posterior lens surfaces, and the zonule. Relevant distances were measured in the resting and accommodated eyes. Stepwise regression analysis determined which variables were the most important predictors. Results. The human vitreous zonule and lens equator move forward (anteriorly) during accommodation, and their movements decline with age, as in the monkey. Over all ages studied, age could explain accommodative amplitude, but not as well as accommodative lens thickening and resting muscle apex thickness did together. Accommodative change in distances between the vitreous zonule insertion zone and the posterior lens equator or muscle apex were important for predicting accommodative lens thickening. Conclusions. Our findings quantify the movements of the zonule and ciliary muscle during accommodation, and identify their age-related changes that could impact the optical change that occurs during accommodation and IOL function. PMID:23745002

  9. Short-Term Adaptive Modification of Dynamic Ocular Accommodation

    PubMed Central

    Bharadwaj, Shrikant R.; Vedamurthy, Indu; Schor, Clifton M.

    2009-01-01

    Purpose Indirect observations suggest that the neural control of accommodation may undergo adaptive recalibration in response to age-related biomechanical changes in the accommodative system. However, there has been no direct demonstration of such an adaptive capability. This investigation was conducted to demonstrate short-term adaptation of accommodative step response dynamics to optically induced changes in neuromuscular demands. Methods Repetitive changes in accommodative effort were induced in 15 subjects (18–34 years) with a double-step adaptation paradigm wherein an initial 2-D step change in blur was followed 350 ms later by either a 2-D step increase in blur (increasing-step paradigm) or a 1.75-D step decrease in blur (decreasing-step paradigm). Peak velocity, peak acceleration, and latency of 2-D single-step test responses were assessed before and after 1.5 hours of training with these paradigms. Results Peak velocity and peak acceleration of 2-D step responses increased after adaptation to the increasing-step paradigm (9/12 subjects), and they decreased after adaptation to the decreasing-step paradigm (4/9 subjects). Adaptive changes in peak velocity and peak acceleration generalized to responses that were smaller (1 D) and larger (3 D) than the 2-D adaptation stimulus. The magnitude of adaptation correlated poorly with the subject's age, but it was significantly negatively correlated with the preadaptation dynamics. Response latency decreased after adaptation, irrespective of the direction of adaptation. Conclusions Short-term adaptive changes in accommodative step response dynamics could be induced, at least in some of our subjects between 18 and 34 years, with a directional bias toward increasing rather than decreasing the dynamics. PMID:19255153

  10. Accommodations for Multiple Choice Tests

    ERIC Educational Resources Information Center

    Trammell, Jack

    2011-01-01

    Students with learning or learning-related disabilities frequently struggle with multiple choice assessments due to difficulty discriminating between items, filtering out distracters, and framing a mental best answer. This Practice Brief suggests accommodations and strategies that disability service providers can utilize in conjunction with…

  11. Objective Amplitude of Accommodation Computed from Optical Quality Metrics Applied to Wavefront Outcomes

    PubMed Central

    López-Gil, Norberto; Fernández-Sánchez, Vicente; Thibos, Larry N.; Montés-Micó, Robert

    2010-01-01

    Purpose We studied the accuracy and precision of 32 objective wavefront methods for finding the amplitude of accommodation obtained in 180 eyes. Methods Ocular accommodation was stimulated with 0.5 D steps in target vergence spanning the full range of accommodation for each subject. Subjective monocular amplitude of accommodation was measured using two clinical methods, using negative lenses and with a custom Badal optometer. Results Both subjective methods gave similar results. Results obtained from the Badal optometer where used to test the accuracy of the objective methods. All objective methods showed lower amplitude of accommodation that the subjective ones by an amount that varied from 0.2 to 1.1 D depending on the method. The precision in this prediction also varied between subjects, with an average standard error of the mean of 0.1 D that decreased with age. Conclusions Depth of field increases subjective of amplitude of accommodation overestimating the objective amplitude obtained with all the metrics used. The change in the negative direction of spherical aberration during accommodation increases the amplitude of accommodation by an amount that varies with age.

  12. Partner Accommodation Moderates Treatment Outcomes for Couple Therapy for Posttraumatic Stress Disorder

    PubMed Central

    Fredman, Steffany J.; Pukay-Martin, Nicole D.; Macdonald, Alexandra; Wagner, Anne C.; Vorstenbosch, Valerie; Monson, Candice M.

    2015-01-01

    Objective Partner accommodation of posttraumatic stress disorder (PTSD) symptoms (i.e., altering one’s own behaviors to minimize patient distress and/or relationship conflict due to patients’ PTSD symptoms) has been shown to be positively associated with patient and partner psychopathology and negatively associated with patient and partner relationship satisfaction cross-sectionally. However, the prognostic value of partner accommodation in treatment outcomes is unknown. The goals of the present study were to determine if partner accommodation decreases as a function of couple therapy for PTSD and if pretreatment partner accommodation moderates the efficacy of couple therapy for PTSD. Method Thirty-nine patients with PTSD and their intimate partners (n = 39) were enrolled in a randomized controlled trial of cognitive-behavioral conjoint therapy (CBCT) for PTSD (Monson & Fredman, 2012) and received CBCT for PTSD immediately or after three months of waiting. Blinded assessors determined clinician-rated PTSD symptoms and patient-rated PTSD and depressive symptoms and relationship satisfaction at baseline, mid-treatment/4 weeks of waiting, and posttreatment/12 weeks of waiting. Results Contrary to expectation, partner accommodation levels did not change over time for either treatment condition. However, baseline partner accommodation significantly moderated treatment outcomes. Higher levels of partner accommodation were associated with greater improvements in PTSD, depressive symptoms, and relationship satisfaction among patients receiving CBCT for PTSD compared with waiting list. At lower levels of partner accommodation, patients in both groups improved or remained at low levels of these outcomes. Conclusions Individuals with PTSD who have more accommodating partners may be particularly well-suited for couple therapy for PTSD. PMID:26501498

  13. Spasm of accommodation associated with closed head trauma.

    PubMed

    Chan, R V Paul; Trobe, Jonathan D

    2002-03-01

    Spasm of accommodation, creating pseudomyopia, is generally associated with miosis and excess convergence as part of spasm of the near reflex. It may also exist as an isolated entity, usually attributed to psychogenic causes. We present six cases of accommodative spasm associated with closed head injury. All patients were male, ranging in age between 16 and 37 years. The degree of pseudomyopia, defined as the difference between manifest and cycloplegic refraction, was 1.5 to 2 diopters. A 3-year trial of pharmacologically induced cycloplegia in one patient did not lead to reversal of the spasm when the cycloplegia was stopped. All patients required the manifest refraction to see clearly at distance. The pseudomyopia endured for at least 7 years following head trauma. This phenomenon may represent traumatic activation or disinhibition of putative brain stem accommodation centers in young individuals.

  14. Static and dynamic crystalline lens accommodation evaluated using quantitative 3-D OCT.

    PubMed

    Gambra, Enrique; Ortiz, Sergio; Perez-Merino, Pablo; Gora, Michalina; Wojtkowski, Maciej; Marcos, Susana

    2013-01-01

    Custom high-resolution high-speed anterior segment spectral domain Optical Coherence Tomography (OCT) provided with automatic quantification and distortion correction algorithms was used to characterize three-dimensionally (3-D) the human crystalline lens in vivo in four subjects, for accommodative demands between 0 to 6 D in 1 D steps. Anterior and posterior lens radii of curvature decreased with accommodative demand at rates of 0.73 and 0.20 mm/D, resulting in an increase of the estimated optical power of the eye of 0.62 D per diopter of accommodative demand. Dynamic fluctuations in crystalline lens radii of curvature, anterior chamber depth and lens thickness were also estimated from dynamic 2-D OCT images (14 Hz), acquired during 5-s of steady fixation, for different accommodative demands. Estimates of the eye power from dynamical geometrical measurements revealed an increase of the fluctuations of the accommodative response from 0.07 D to 0.47 D between 0 and 6 D (0.044 D per D of accommodative demand). A sensitivity analysis showed that the fluctuations of accommodation were driven by dynamic changes in the lens surfaces, particularly in the posterior lens surface.

  15. Static and dynamic crystalline lens accommodation evaluated using quantitative 3-D OCT

    PubMed Central

    Gambra, Enrique; Ortiz, Sergio; Perez-Merino, Pablo; Gora, Michalina; Wojtkowski, Maciej; Marcos, Susana

    2013-01-01

    Custom high-resolution high-speed anterior segment spectral domain Optical Coherence Tomography (OCT) provided with automatic quantification and distortion correction algorithms was used to characterize three-dimensionally (3-D) the human crystalline lens in vivo in four subjects, for accommodative demands between 0 to 6 D in 1 D steps. Anterior and posterior lens radii of curvature decreased with accommodative demand at rates of 0.73 and 0.20 mm/D, resulting in an increase of the estimated optical power of the eye of 0.62 D per diopter of accommodative demand. Dynamic fluctuations in crystalline lens radii of curvature, anterior chamber depth and lens thickness were also estimated from dynamic 2-D OCT images (14 Hz), acquired during 5-s of steady fixation, for different accommodative demands. Estimates of the eye power from dynamical geometrical measurements revealed an increase of the fluctuations of the accommodative response from 0.07 D to 0.47 D between 0 and 6 D (0.044 D per D of accommodative demand). A sensitivity analysis showed that the fluctuations of accommodation were driven by dynamic changes in the lens surfaces, particularly in the posterior lens surface. PMID:24049680

  16. Accommodative Lag by Autorefraction and Two Dynamic Retinoscopy Methods

    PubMed Central

    2008-01-01

    Purpose To evaluate two clinical procedures, MEM and Nott retinoscopy, for detecting accommodative lags 1.00 diopter (D) or greater in children as identified by an open-field autorefractor. Methods 168 children 8 to <12 years old with low myopia, normal visual acuity, and no strabismus participated as part of an ancillary study within the screening process for a randomized trial. Accommodative response to a 3.00 D demand was first assessed by MEM and Nott retinoscopy, viewing binocularly with spherocylindrical refractive error corrected, with testing order randomized and each performed by a different masked examiner. The response was then determined viewing monocularly with spherical equivalent refractive error corrected, using an open-field autorefractor, which was the gold standard used for eligibility for the clinical trial. Sensitivity and specificity for accommodative lags of 1.00 D or more were calculated for each retinoscopy method compared to the autorefractor. Results 116 (69%) of the 168 children had accommodative lag of 1.00 D or more by autorefraction. MEM identified 66 children identified by autorefraction for a sensitivity of 57% (95% CI = 47% to 66%) and a specificity of 63% (95% CI = 49% to 76%). Nott retinoscopy identified 35 children for a sensitivity of 30% (95% CI = 22% to 39%) and a specificity of 81% (95% CI = 67% to 90%). Analysis of receiver operating characteristic (ROC) curves constructed for MEM and for Nott retinoscopy failed to reveal alternate cut points that would improve the combination of sensitivity and specificity for identifying accommodative lag ≥ 1.00 D as defined by autorefraction. Conclusions Neither MEM nor Nott retinoscopy provided adequate sensitivity and specificity to identify myopic children with accommodative lag ≥ 1.00 D as determined by autorefraction. A variety of methodological differences between the techniques may contribute to the modest to poor agreement. PMID:19214130

  17. The stability of steady state accommodation in human infants

    PubMed Central

    Candy, T. Rowan; Bharadwaj, Shrikant R.

    2009-01-01

    Retinal image quality in infants is largely determined by the accuracy and the stability of their accommodative responses. Although the accuracy of infants’ accommodation has been investigated previously, little is known about the stability of their responses. We performed two experiments that characterized the stability of infants’ steady state accommodation. Analyses were performed in the time domain (root mean square [RMS] deviation) and in the frequency domain (spectral analysis). In Experiment 1, accommodation responses were recorded for a period of 3 s from the left eye of four groups of infants (8–10, 11–13, 14–19, and 20–30 weeks of age) and eight prepresbyopic adults while they focused on a small toy placed at a dioptric viewing distance of 1.0 D (at 1 m). In Experiment 2, accommodation responses were recorded for a period of 14 s from the left eye of a group of 8- to 12-week-old infants and six prepresbyopic adults while they focused on a cartoon image placed at three different dioptric viewing distances (1.25, 2.0, and 3.0 D). The data, collected using a photorefractor sampling at 25 Hz, showed two important characteristics. First, the RMS deviations and the power were quantitatively similar across different infant age groups, and they were significantly larger in infants than in adults. Second, the overall and relative power also increased with the dioptric viewing distance both in infants and adults. At all three dioptric viewing distances, the measures of power were larger in infants than in adults. These data demonstrate that infants’ accommodative responses contain instabilities that are qualitatively very similar to those observed in adults. However, the larger RMS deviations suggest that infants are likely to experience larger fluctuations in retinal image quality than adults. PMID:17997659

  18. Accommodating World Englishes in Developing EFL Learners' Oral Communication

    ERIC Educational Resources Information Center

    Mukminatien, Nur

    2012-01-01

    This article aims to discuss issues of World Englishes (WEs) and the implications in ELT. It explores the extent to which WEs are taken into account as emerging English varieties different from inner circle varieties, how WEs should be accommodated by English teachers, and which standard to adopt to accommodate learner's linguistic needs for…

  19. Convergence and accommodation development is pre-programmed in premature infants

    PubMed Central

    Horwood, Anna M; Toor, Sonia S; Riddell, Patricia M

    2015-01-01

    Purpose This study investigated whether vergence and accommodation development in pre-term infants is pre-programmed or is driven by experience. Methods 32 healthy infants, born at mean 34 weeks gestation (range 31.2-36 weeks) were compared with 45 healthy full-term infants (mean 40.0 weeks) over a 6 month period, starting at 4-6 weeks post-natally. Simultaneous accommodation and convergence to a detailed target were measured using a Plusoptix PowerRefII infra-red photorefractor as a target moved between 0.33m and 2m. Stimulus/response gains and responses at 0.33m and 2m were compared by both corrected (gestational) age and chronological (post-natal) age. Results When compared by their corrected age, pre-term and full-term infants showed few significant differences in vergence and accommodation responses after 6-7 weeks of age. However, when compared by chronological age, pre-term infants’ responses were more variable, with significantly reduced vergence gains, reduced vergence response at 0.33m, reduced accommodation gain, and increased accommodation at 2m, compared to full-term infants between 8-13 weeks after birth. Conclusions When matched by corrected age, vergence and accommodation in pre-term infants show few differences from full-term infants’ responses. Maturation appears pre-programmed and is not advanced by visual experience. Longer periods of immature visual responses might leave pre-term infants more at risk of development of oculomotor deficits such as strabismus. PMID:26275135

  20. 14 CFR 382.81 - For which passengers must carriers make seating accommodations?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false For which passengers must carriers make seating accommodations? 382.81 Section 382.81 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF... TRAVEL Seating Accommodations § 382.81 For which passengers must carriers make seating accommodations? As...

  1. 14 CFR 382.83 - Through what mechanisms do carriers make seating accommodations?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Through what mechanisms do carriers make seating accommodations? 382.83 Section 382.83 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF... TRAVEL Seating Accommodations § 382.83 Through what mechanisms do carriers make seating accommodations...

  2. 14 CFR 382.81 - For which passengers must carriers make seating accommodations?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false For which passengers must carriers make seating accommodations? 382.81 Section 382.81 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF... TRAVEL Seating Accommodations § 382.81 For which passengers must carriers make seating accommodations? As...

  3. 14 CFR 382.83 - Through what mechanisms do carriers make seating accommodations?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Through what mechanisms do carriers make seating accommodations? 382.83 Section 382.83 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF... TRAVEL Seating Accommodations § 382.83 Through what mechanisms do carriers make seating accommodations...

  4. 14 CFR 382.83 - Through what mechanisms do carriers make seating accommodations?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Through what mechanisms do carriers make seating accommodations? 382.83 Section 382.83 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF... TRAVEL Seating Accommodations § 382.83 Through what mechanisms do carriers make seating accommodations...

  5. 14 CFR 382.83 - Through what mechanisms do carriers make seating accommodations?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Through what mechanisms do carriers make seating accommodations? 382.83 Section 382.83 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF... TRAVEL Seating Accommodations § 382.83 Through what mechanisms do carriers make seating accommodations...

  6. 14 CFR 382.83 - Through what mechanisms do carriers make seating accommodations?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Through what mechanisms do carriers make seating accommodations? 382.83 Section 382.83 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF... TRAVEL Seating Accommodations § 382.83 Through what mechanisms do carriers make seating accommodations...

  7. Red-green opponent channel mediation of control of human ocular accommodation.

    PubMed Central

    Kotulak, J C; Morse, S E; Billock, V A

    1995-01-01

    1. It has been hypothesized, but not verified empirically, that the control of human ocular accommodation is mediated by either the red-green or yellow-blue colour channels. Our goal was to determine experimentally whether the red-green channel by itself could influence the accommodative response. 2. To find out, we isolated the red-green channel through chromatic bandpass filtering and measured accommodation under dynamic and static conditions. The effect of this filtering was to modulate the red-green channel without disturbing either the yellow-blue or luminance channels. 3. Accommodative gain (ratio of response to stimulus amplitude) declined monotonically with decreasing bandwidth under dynamic conditions. Because the outputs of both the luminance and yellow-blue colour channels did not vary with bandwidth, the only explanation is that the red-green opponent process was responsible for the effect. 4. Under static conditions, however, accommodation was independent of bandwidth. This may be attributable to the decreased sensitivity to chromatic contrast that occurs at low temporal frequencies. PMID:7738858

  8. Ultramicroporous Carbon through an Activation-Free Approach for Li-S and Na-S Batteries in Carbonate-Based Electrolyte.

    PubMed

    Hu, Lei; Lu, Yue; Zhang, Tianwen; Huang, Tao; Zhu, Yongchun; Qian, Yitai

    2017-04-26

    We report an activation-free approach for fabricating ultramicroporous carbon as an accommodation of sulfur molecules for Li-S and Na-S batteries applications in carbonate-based electrolyte. Because of the high specific surface area of 967 m 2 g -1 , as well as 51.8% of the pore volume is contributed by ultramicropore with pore size less than 0.7 nm, sulfur cathode exhibits superior electrochemical behavior in carbonate-based electrolyte with a capacity of 507.9 mA h g -1 after 500 cycles at 2 C in Li-S batteries and 392 mA h g -1 after 200 cycles at 1 C in Na-S batteries, respectively.

  9. 28 CFR 42.511 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... needed. A reasonable accommodation may require a recipient to bear more than an insignificant economic... inconvenience which does not bear on the ability of the handicapped individual to perform the essential duties...

  10. OCT-based full crystalline lens shape change during accommodation in vivo.

    PubMed

    Martinez-Enriquez, Eduardo; Pérez-Merino, Pablo; Velasco-Ocana, Miriam; Marcos, Susana

    2017-02-01

    The full shape of the accommodating crystalline lens was estimated using custom three-dimensional (3-D) spectral OCT and image processing algorithms. Automatic segmentation and distortion correction were used to construct 3-D models of the lens region visible through the pupil. The lens peripheral region was estimated with a trained and validated parametric model. Nineteen young eyes were measured at 0-6 D accommodative demands in 1.5 D steps. Lens volume, surface area, diameter, and equatorial plane position were automatically quantified. Lens diameter & surface area correlated negatively and equatorial plane position positively with accommodation response. Lens volume remained constant and surface area decreased with accommodation, indicating that the lens material is incompressible and the capsular bag elastic.

  11. Reasonable Accommodation in Training Safety.

    ERIC Educational Resources Information Center

    Sandoz, Jeff

    A pictograph and icon-driven training program has been specifically designed for educators who are responsible for teaching the developmentally disabled regarding the safe use of hazardous chemicals. In alignment with the Americans with Disabilities Act, it offers "reasonable accommodation" by those who educate and train this special…

  12. Cost of workplace accommodations for individuals with disabilities: with or without personal assistance services.

    PubMed

    Solovieva, Tatiana I; Walls, Richard T; Hendricks, Deborah J; Dowler, Denetta L

    2009-10-01

    This study compared the expense associated with use of personal assistance services (PAS) for individuals with disabilities to the expense incurred by individuals with disabilities who did not use PAS. The intent of this investigation was to assess the disability accommodation costs and benefits of PAS and non-PAS cases. The study uses 1,182 follow-up telephone surveys and 24 telephone interviews of employers who had previously contacted the Job Accommodation Network (JAN) to discuss disability-related accommodations for an employee or potential employee that were conducted from January 2004 through December 2006. The survey included 69 employers who had considered PAS. The surveys were conducted by the University of Iowa's Law, Health Policy, and Disability Center, which contacted employers who had previously contacted JAN for consultation on workplace accommodations. The interviews were conducted by the International Center for Disability Information at West Virginia University. Key findings point to the costs associated with PAS cases and with cases not involving PAS accommodations. As reported by the employers, the median "one-time cost" of accommodations (not $0) for non-PAS cases was $500. The median "one-time cost" of accommodations (not $0) for PAS cases was $1,850. When $0 cost of accommodations on PAS cases was factored in with "one-time cost" of accommodations for PAS cases, the median cost was $0. For non-PAS cases of accommodations, when $0 cost of accommodations was considered, the outcome was a median cost of $0. The annual cost for PAS accommodations was a median cost of $8,000 in comparison to $2,000 for non-PAS. The median dollar amount estimates of direct benefits were $1,600 for PAS accommodations, similar to $1,500 for non-PAS. The most frequently mentioned benefits from PAS accommodations were (a) increased productivity, (b) increased diversity, (c) retention of a valued employee, (d) improved interactions with co-workers, (e) increased

  13. Workplace Accommodation for Persons With IBD: What Is Needed and What Is Accessed.

    PubMed

    Chhibba, Tarun; Walker, John R; Sexton, Kathryn; Restall, Gayle; Ivekovic, Melony; Shafer, Leigh Ann; Singh, Harminder; Targownik, Laura E; Bernstein, Charles N

    2017-10-01

    People with inflammatory bowel disease (IBD) often experience periods of illness that interfere with their ability to work. We aimed to understand the need for workplace accommodation during periods of acute illness among persons IBD. Participants were recruited from the population-based University of Manitoba Research Registry and received a survey including questions assessing experiences with workplace accommodations. Data were analyzed using descriptive statistics and multivariate logistic regression modelling. A total of 1143 individuals responded to the survey (46% response rate), of whom 881 had experienced IBD symptoms in the workplace and were included in the analysis. The mean age was 48.3 years (standard deviation, 10.9); 61% were female. Mean IBD duration was 20.6 years (standard deviation, 10.5). Most respondents (73%) described IBD symptoms experienced in the workplace as severe to very severe. The most commonly required accommodations were time to go to medical appointments during working hours (81%), easy access to a toilet (71%), and a chance to take a break when not feeling well (54%). Most accommodations were arranged informally or through a supervisor. The accommodations required were very or somewhat easy to arrange about half the time. Being female, having high symptom severity, and high level of current distress were associated with a need for more accommodations, difficulty implementing accommodations, and not asking for needed accommodations. This study provides important information as to the types of accommodations that are necessary, common practices arranging for these, and level of difficulty arranging accommodations. Furthermore, characteristics associated with greater need for accommodation, reluctance to ask for them, and difficulty in arranging them were identified. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

  14. [Finite Element Modelling of the Eye for the Investigation of Accommodation].

    PubMed

    Martin, H; Stachs, O; Guthoff, R; Grabow, N

    2016-12-01

    Background: Accommodation research increasingly uses engineering methods. This article presents the use of the finite element method in accommodation research. Material and Methods: Geometry, material data and boundary conditions are prerequisites for the application of the finite element method. Published data on geometry and materials are reviewed. It is shown how boundary conditions are important and how they influence the results. Results: Two dimensional and three dimensional models of the anterior chamber of the eye are presented. With simple two dimensional models, it is shown that realistic results for the accommodation amplitude can always be achieved. More complex three dimensional models of the accommodation mechanism - including the ciliary muscle - require further investigations of the material data and of the morphology of the ciliary muscle, if they are to achieve realistic results for accommodation. Discussion and Conclusion: The efficiency and the limitations of the finite element method are especially clear for accommodation. Application of the method requires extensive preparation, including acquisition of geometric and material data and experimental validation. However, a validated model can be used as a basis for parametric studies, by systematically varying material data and geometric dimensions. This allows systematic investigation of how essential input parameters influence the results. Georg Thieme Verlag KG Stuttgart · New York.

  15. Transition to Postsecondary: New Documentation Guidance for Access to Accommodations

    ERIC Educational Resources Information Center

    Klotz, Mary Beth

    2012-01-01

    The Association on Higher Education and Disability (AHEAD) recently developed a conceptual framework that substantially revises its guidance for disability documentation for accommodations in higher education settings. This new document, "Supporting Accommodation Requests: Guidance on Documentation Practices," was written in response to the…

  16. Is There a Downside of Job Accommodations? An Employee Perspective on Individual Change Processes

    PubMed Central

    Kensbock, Julia M.; Boehm, Stephan A.; Bourovoi, Kirill

    2017-01-01

    By modifying the work environments, work routines, and work tasks of employees with health restrictions, organizations can effectively help them continue to perform their jobs successfully. As such, job accommodations are an effective tool to secure the continued employment of aging workers who develop disabilities across their life span. However, while accommodations tackle health-related performance problems, they might create new challenges on the part of the affected employee. Building on the organizational change and accommodations literatures, we propose a theoretical framework of negative experiences during accommodation processes and apply it to qualitative data from group interviews with 73 manufacturing workers at a German industrial company who were part of the company's job accommodation program. Although problems associated with health-related impairments were mostly solved by accommodation, affected employees with disabilities reported about interpersonal problems and conflicts similar to those that typically occur during organizational change. Lack of social support as well as poor communication and information were raised as criticisms. Furthermore, our findings indicate that discrimination, bullying, and maltreatment appear to be common during accommodation processes. To make accommodation processes more successful, we derive recommendations from the organizational change literature and apply it to the accommodation context. We also emphasize unique characteristics of the accommodation setting and translate these into practical implications. PMID:28979218

  17. Accommodations Quality for Students Who Are d/Deaf or Hard of Hearing

    ERIC Educational Resources Information Center

    Cawthon, Stephanie W.; Leppo, Rachel

    2013-01-01

    Students who are d/Deaf or hard of hearing often receive accommodations that are intended to increase access to the educational environment. The authors provide the results of a large national study of accommodations use in secondary and postsecondary settings. The article focuses on three aspects of accommodations use: access, quality, and…

  18. Visual-Accommodation Trainer/Tester

    NASA Technical Reports Server (NTRS)

    Randle, Robert J., Jr.

    1986-01-01

    Ophthalmic instrument tests and helps develop focusing ability. Movable stage on a fixed base permits adjustment of effective target position as perceived by subject. Various apertures used to perform tests and training procedures. Ophthalmic instrument provides four functions: it measures visual near and far points; provides focus stimulus in vision research; measures visual-accommodation resting position; can be used to train for volitional control of person's focus response.

  19. The effect of a beta-adrenoceptor antagonist on accommodative adaptation in Hong Kong children.

    PubMed

    Chen, Jennifer C; Schmid, Katrina L; Brown, Brian; Edwards, Marion H

    2005-03-01

    Increased susceptibility to nearwork-induced accommodative adaptation has been suggested as a risk factor for myopia development. We investigated whether accommodative adaptation may explain in part the high prevalence of myopia in Hong Kong children and examined the effect of beta-antagonism with topical timolol maleate on accommodative adaptation. Thirty children (10 emmetropes and 20 myopes) aged between 8 and 12 years were recruited. Tonic accommodation was measured before and after 5 min of video game-playing using an open-field Shin-Nippon autorefractor. Measurements were repeated 30 min after timolol instillation. Children with progressing myopia demonstrated accommodative adaptation following the near task, whereas stable myopes showed counter-adaptive, hyperopic accommodative changes. Timolol increased the magnitude of accommodative adaptation in the stable myopes but had little effect on responses of the progressing myopes or emmetropes. Neuropharmacological modulation of the accommodative system may have a possible etiological role in the progression of myopia.

  20. Thermally Conductive Metal-Tube/Carbon-Composite Joints

    NASA Technical Reports Server (NTRS)

    Copeland, Robert J.

    2004-01-01

    An improved method of fabricating joints between metal and carbon-fiber-based composite materials in lightweight radiators and heat sinks has been devised. Carbon-fiber-based composite materials have been used in such heat-transfer devices because they offer a combination of high thermal conductivity and low mass density. Metal tubes are typically used to carry heat-transfer fluids to and from such heat-transfer devices. The present fabrication method helps to ensure that the joints between the metal tubes and the composite-material parts in such heat-transfer devices have both (1) the relatively high thermal conductances needed for efficient transfer of heat and (2) the flexibility needed to accommodate differences among thermal expansions of dissimilar materials in operation over wide temperature ranges. Techniques used previously to join metal tubes with carbon-fiber-based composite parts have included press fitting and bonding with epoxy. Both of these prior techniques have been found to yield joints characterized by relatively high thermal resistances. The present method involves the use of a solder (63 percent Sn, 37 percent Pb) to form a highly thermally conductive joint between a metal tube and a carbon-fiber-based composite structure. Ordinarily, the large differences among the coefficients of thermal expansion of the metal tube, solder, and carbon-fiber-based composite would cause the solder to pull away from the composite upon post-fabrication cooldown from the molten state. In the present method, the structure of the solder is modified (see figure) to enable it to deform readily to accommodate the differential thermal expansion.

  1. Injured workers' perspectives on how workplace accommodations are conceptualized and delivered following electrical injuries.

    PubMed

    Stergiou-Kita, Mary; Mansfield, Elizabeth; Colantonio, Angela

    2014-06-01

    Returning to work following an electrical injury can be challenging due to the confluence of physical, cognitive and emotional impairments. Workplace accommodations can facilitate return to work. However, while electrical injuries can have potentially devastating consequences, there is a dearth of understanding of how workplace accommodations are obtained following electrical injury. This paper explores workers' experiences of returning to work and accommodations following an occupation electrical injury. Thirteen semi-structured qualitative telephone interviews were conducted with injured workers recruited from acute and rehabilitation burns programs in Ontario, Canada. Thematic analysis was employed to identify themes related to the request and provision of accommodations. Findings reveal that accommodations are most frequently narrowly defined in relation to physical work restrictions, leading to the exclusion of cognitive and psychosocial concerns. Challenges within the accommodations process such as perceived legitimacy, a do-it-yourself approach to accommodations, and concerns regarding job security can also influence workers' decisions to request accommodations. Process elements that facilitate the effective provision of workplace accommodations include: (1) finding a "just right" fit between workers' abilities and assigned tasks and duties (2) establishing effective lines of communication between relevant stakeholders; (3) prompt response to needs; (4) having a knowledgeable individual in a position of power to advocate on workers' behalf. Further education regarding electrical injuries and workplace accommodations is warranted to increase workers', employers', health and insurance personnels' knowledge about electrical injury and best practices for providing workplace accommodations.

  2. A survey of anthropometry and physical accommodation in ergonomics curricula.

    PubMed

    Garneau, Christopher J; Parkinson, Matthew B

    2016-01-01

    The size and shape of users are an important consideration for many products and environments. Designers and engineers in many disciplines must often accommodate these attributes to meet objectives such as fit and safety. When practitioners have academic training in addressing these issues, it is typically through courses in Human Factors/Ergonomics (HF/E). This paper investigates education related to physical accommodation and offers suggestions for improvement. A survey was conducted wherein 21 instructors at 18 universities in the United States provided syllabi for 29 courses, which were analysed to determine topics related to anthropometry and resources used for the courses. The results show that within the U.S., anthropometry is covered in the majority of courses discussing physical ergonomics, but important related concepts were often omitted (e.g., digital human modelling, multivariate accommodation and variability across global populations). Curricula could be improved by incorporating more accurate anthropometry, multivariate problems and interactive online tools. This paper describes a study investigating collegiate ergonomics courses within the U.S. in the area of physical accommodation. Course schedules and texts were studied for their treatment of several topics related to accommodating the spatial requirements (anthropometry) of users. Recommendations are made for improving course curricula.

  3. OCT-based full crystalline lens shape change during accommodation in vivo

    PubMed Central

    Martinez-Enriquez, Eduardo; Pérez-Merino, Pablo; Velasco-Ocana, Miriam; Marcos, Susana

    2017-01-01

    The full shape of the accommodating crystalline lens was estimated using custom three-dimensional (3-D) spectral OCT and image processing algorithms. Automatic segmentation and distortion correction were used to construct 3-D models of the lens region visible through the pupil. The lens peripheral region was estimated with a trained and validated parametric model. Nineteen young eyes were measured at 0-6 D accommodative demands in 1.5 D steps. Lens volume, surface area, diameter, and equatorial plane position were automatically quantified. Lens diameter & surface area correlated negatively and equatorial plane position positively with accommodation response. Lens volume remained constant and surface area decreased with accommodation, indicating that the lens material is incompressible and the capsular bag elastic. PMID:28270993

  4. Accommodation-induced variations in retinal thickness measured by spectral domain optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Fan, Shanhui; Sun, Yong; Dai, Cuixia; Zheng, Haihua; Ren, Qiushi; Jiao, Shuliang; Zhou, Chuanqing

    2014-09-01

    To research retinal stretching or distortion with accommodation, accommodation-induced changes in retinal thickness (RT) in the macular area were investigated in a population of young adults (n=23) by using a dual-channel spectral domain optical coherence tomography (SD-OCT) system manufactured in-house for this study. This dual-channel SD-OCT is capable of imaging the cornea and retina simultaneously with an imaging speed of 24 kHz A-line scan rate, which can provide the anatomical dimensions of the eye, including the RT and axial length. Thus, the modification of the RT with accommodation can be calculated. A significant decrease in the RT (13.50±1.25 μm) was observed during maximum accommodation. In the 4 mm×4 mm macular area centered at the fovea, we did not find a significant quadrant-dependent difference in retinal volume change, which indicates that neither retinal stretching nor distortion was quadrant-dependent during accommodation. We speculate that the changes in RT with maximum accommodation resulted from accommodation-induced ciliary muscle contractions.

  5. Improving Meaningful Use of Accommodations by Multilingual Learners

    ERIC Educational Resources Information Center

    Shafer Willner, Lynn; Mokhtari, Kouider

    2018-01-01

    For more than two decades, accommodations have served as the primary strategy for ensuring the valid participation of multilingual learners (MLLs) in high-stakes summative assessments. Using historical analyses of the evolution of testing accommodation guidelines and related instructional practices, the authors explain how the application of…

  6. Semicommunication and Accommodation: Observations from the Linguistic Situation in Scandinavia.

    ERIC Educational Resources Information Center

    Braunmuller, Kurt

    2002-01-01

    Focuses on semicommunication and accommodation and discusses two longer extracts from a large corpus of authentic communication from Scandinavia. Various aspects of a comprehensive model of semicommunication are presented and discussed, showing code switching and accommodation are not considered antagonistic but rather as scalar phenomena covering…

  7. Voltage-controlled IPMC actuators for accommodating intra-ocular lens systems

    NASA Astrophysics Data System (ADS)

    Horiuchi, Tetsuya; Mihashi, Toshifumi; Fujikado, Takashi; Oshika, Tetsuro; Asaka, Kinji

    2017-04-01

    An ion polymer-metal composite (IPMC) actuator has unique performance characteristics that were applied in this study for use within the eye. Cataracts are a common eye disease causing clouding of the lens. To treat cataracts, surgeons replace clouded lenses with intraocular lenses (IOLs). However, patients who receive this treatment must still wear reading glasses for tasks requiring close-up vision. We suggest a new voltage-controlled accommodating IOL consisting of an IPMC actuator to change the lens’ focus. We examined the relationship between the displacement performance of an IPMC actuator and the accommodating range of the IOL using in vitro experiments. We show that this system has an accommodating range of approximately 1.15 D under an applied voltage of ±1.2 V. By Lagrange interpolation, we estimate that with an IPMC actuator displacement of 0.14 mm, we can achieve a refractive power of 4 D, which is equivalent to the accommodating range of a 40 year old person.

  8. Accommodating Autistics and Treating Autism: Can We Have Both?

    PubMed

    Lim, Chong-Ming

    2015-10-01

    One of the central claims of the neurodiversity movement is that society should accommodate the needs of autistics, rather than try to treat autism. People have variously tried to reject this accommodation thesis as applicable to all autistics. One instance is Pier Jaarsma and Stellan Welin, who argue that the thesis should apply to some but not all autistics. They do so via separating autistics into high- and low-functioning, on the basis of IQ and social effectiveness or functionings. I reject their grounds for separating autistics. IQ is an irrelevant basis for separating autistics. Charitably rendering it as referring to more general capacities still leaves us mistaken about the roles they play in supporting the accommodation thesis. The appeal to social effectiveness or functionings relies on standards that are inapplicable to autistics, and which risks being deaf to the point of their claims. I then consider if their remaining argument concerning autistic culture may succeed independently of the line they draw. I argue that construing autistics' claims as beginning from culture mistakes their status, and may even detract from their aims. Via my discussion of Jaarsma and Welin, I hope to point to why the more general strategy of separating autistics, in response to the accommodation thesis, does not fully succeed. Finally, I sketch some directions for future discussions, arguing that we should instead shift our attention to consider another set of questions concerning the costs and extent of change required to accommodate all autistics. © 2015 John Wiley & Sons Ltd.

  9. Accommodative and convergence response to computer screen and printed text

    NASA Astrophysics Data System (ADS)

    Ferreira, Andreia; Lira, Madalena; Franco, Sandra

    2011-05-01

    The aim of this work was to find out if differences exist in accommodative and convergence response for different computer monitors' and a printed text. It was also tried to relate the horizontal heterophoria value and accommodative response with the symptoms associated with computer use. Two independents experiments were carried out in this study. The first experiment was measuring the accommodative response on 89 subjects using the Grand Seiko WAM-5500 (Grand Seiko Co., Ltd., Japan). The accommodative response was measured using three computer monitors: a 17-inch cathode ray tube (CRT), two liquid crystal displays LCDs, one 17-inch (LCD17) and one 15 inches (LCD15) and a printed text. The text displayed was always the same for all the subjects and tests. A second experiment aimed to measure the value of habitual horizontal heterophoria on 80 subjects using the Von Graefe technique. The measurements were obtained using the same target presented on two different computer monitors, one 19-inch cathode ray tube (CRT) and other 19 inches liquid crystal displays (LCD) and printed on paper. A small survey about the incidence and prevalence of symptoms was performed similarly in both experiments. In the first experiment, the accommodation response was higher in the CRT and LCD's than for paper. There were not found significantly different response for both LCD monitors'. The second experiment showed that, the heterophoria values were similar for all the stimuli. On average, participants presented a small exophoria. In both experiments, asthenopia was the symptom that presented higher incidence. There are different accommodative responses when reading on paper or on computer monitors. This difference is more significant for CRT monitors. On the other hand, there was no difference in the values of convergence for the computer monitors' and paper. The symptoms associated with the use of computers are not related with the increase in accommodation and with the horizontal

  10. An initial study of family accommodation in children and adolescents with chronic tic disorders.

    PubMed

    Storch, Eric A; Johnco, Carly; McGuire, Joseph F; Wu, Monica S; McBride, Nicole M; Lewin, Adam B; Murphy, Tanya K

    2017-01-01

    This initial study examined the nature, incidence, and clinical correlates of family accommodation in youth with tic disorders, and validated a brief self-report measure of tic-related family accommodation, the Tic Family Accommodation Scale (TFAS). Seventy-five youth aged 6-18 who were diagnosed with a tic disorder and their parent completed a diagnostic clinical interview, and clinician and parent-report measures of tic severity, depressive symptoms, anxiety symptoms, behavioral problems, family accommodation and impairment. An exploratory factor analysis of the TFAS showed a two-factor structure, with good internal consistency for the Total score, Modification of Child Environment and Modification of Parent Environment subscales (α = 0.88, 0.86, and 0.81, respectively). Family accommodation was not associated with tic severity. Family accommodation was associated with increased anxiety and depressive symptoms, higher externalizing, rule breaking, aggressive behaviors and social problems, and with greater tic-related functional impairment. Anxiety and externalizing problems (but not depressive symptoms) predicted family accommodation when controlling for tic severity. Family accommodation predicted high levels of functional impairment over and above the effect of tic severity, anxiety, depression and externalizing problems. Family accommodation is a common phenomenon for youth with tic disorders, with modifications typically encompassing changes to the child and/or parent environments. Accommodation was not associated with tic severity, but was related to higher levels of anxiety, depressive symptoms, externalizing symptoms, aggression, and rule breaking behaviors. Results suggest that other emotional symptoms are more likely to drive accommodation practices than the tic symptoms per se.

  11. Quantifying large-scale historical formation of accommodation in the Mississippi Delta

    USGS Publications Warehouse

    Morton, Robert A.; Bernier, Julie C.; Kelso, Kyle W.; Barras, John A.

    2010-01-01

    Large volumes of new accommodation have formed within the Mississippi Delta plain since the mid-1950s in association with rapid conversion of coastal wetlands to open water. The three-dimensional aspects and processes responsible for accommodation formation were quantified by comparing surface elevations, water depths, and vertical displacements of stratigraphic contacts that were correlated between short sediment cores. Integration of data from remotely sensed images, sediment cores, and water-depth surveys at 10 geologically diverse areas in the delta plain provided a basis for estimating the total volume of accommodation formed by interior-wetland subsidence and subsequent erosion. Results indicate that at most of the study areas subsidence was a greater contributor than erosion to the formation of accommodation associated with wetland loss. Tens of millions of cubic meters of accommodation formed rapidly at each of the large open-water bodies that were formerly continuous interior delta-plain marsh. Together the individual study areas account for more than 440 × 106 × m3 of new accommodation that formed as holes in the Mississippi River delta-plain fabric between 1956 and 2004. This large volume provides an estimate of the new sediment that would be needed just at the study areas to restore the delta-plain wetlands to their pre-1956 areal extent and elevations.

  12. Disclosure, accommodations and self-care at work among adolescents with disabilities.

    PubMed

    Lindsay, Sally; McDougall, Carolyn; Sanford, Robyn

    2013-01-01

    The purpose of this study is to explore whether adolescents with disabilities disclose their condition and what types of accommodations are requested at work. In-depth, qualitative semi-structured interviews were conducted with 18 adolescents with a physical and/or mobility-related disability. We also reviewed their self- and staff assessments completed throughout an employment training program in which they took part. The findings show that most youth were able to disclose their conditions and recognize some of their limitations in performing tasks at work. Youth requested physical accommodations, more time to complete tasks and cognitive accommodations. Youth also performed several self-care tasks to manage their disability at work including personal care, pain management and fatigue. Within the context of this employment training program, youth were able to disclose their condition to their employer, ask for accommodations and manage their disability in the workplace. Educators and clinicians should: Assist youth in understanding whether, when and how to disclose their disability to their potential employer. Help youth to understand what accommodations are available to them in the workplace and how to access them, to help them to perform their job effectively. Coach youth on how to manage their disability in a work context, especially with regard to personal care, pain management and fatigue. Encourage and facilitate participation in experience-based opportunities to practice disclosure, requesting accommodations and self-management.

  13. Molecular-dynamics study on characteristics of energy and tangential momentum accommodation coefficients

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Hiroki; Matsuda, Yu; Niimi, Tomohide

    2017-07-01

    Gas-surface interaction is studied by the molecular dynamics method to investigate qualitatively characteristics of accommodation coefficients. A large number of trajectories of gas molecules colliding to and scattering from a surface are statistically analyzed to calculate the energy (thermal) accommodation coefficient (EAC) and the tangential momentum accommodation coefficient (TMAC). Considering experimental measurements of the accommodation coefficients, the incident velocities are stochastically sampled to represent a bulk condition. The accommodation coefficients for noble gases show qualitative coincidence with experimental values. To investigate characteristics of these accommodation coefficients in detail, the gas-surface interaction is parametrically studied by varying the molecular mass of gas, the gas-surface interaction strength, and the molecular size of gas, one by one. EAC increases with increasing every parameter, while TMAC increases with increasing the interaction strength, but decreases with increasing the molecular mass and the molecular size. Thus, contradictory results in experimentally measured TMAC for noble gases could result from the difference between the surface conditions employed in the measurements in the balance among the effective parameters of molecular mass, interaction strength, and molecular size, due to surface roughness and/or adsorbed molecules. The accommodation coefficients for a thermo-fluid dynamics field with a temperature difference between gas and surface and a bulk flow at the same time are also investigated.

  14. [Spasm of accommodation].

    PubMed

    Lindberg, Laura

    2014-01-01

    Spasm of accommodation refers to prolonged contraction of the ciliary muscle, most commonly causing pseudomyopia to varying degrees in both eyes by keeping the lens in a state of short sightedness. It may also be manifested as inability to allow the adaptation spasticity prevailing in the ciliary muscle relax without measurable myopia. As a rule, this is a functional ailment triggered by prolonged near work and stress. The most common symptoms include blurring of distance vision, varying visual acuity as well as pains in the orbital region and the head, progressing into a chronic state. Cycloplegic eye drops are used as the treatment.

  15. Accuracy of accommodation in heterophoric patients: testing an interaction model in a large clinical sample.

    PubMed

    Hasebe, Satoshi; Nonaka, Fumitaka; Ohtsuki, Hiroshi

    2005-11-01

    A model of the cross-link interactions between accommodation and convergence predicted that heterophoria can induce large accommodation errors (Schor, Ophthalmic Physiol. Opt. 1999;19:134-150). In 99 consecutive patients with intermittent tropia or decompensated phoria, we tested these interactions by comparing their accommodative responses to a 2.50-D target under binocular fused conditions (BFC) and monocular occluded conditions (MOC). The accommodative response in BFC frequently differed from that in MOC. The magnitude of the accommodative errors in BFC, ranging from an accommodative lag of 1.80 D (in an esophoric patient) to an accommodative lead of 1.56 D (in an exophoric patient), was correlated with distance heterophoria and uncorrected refractive errors. These results indicate that heterophoria affects the accuracy of accommodation to various degrees, as the model predicted, and that an accommodative error larger than the depth of focus of the eye occurs in exchange for binocular single vision in some heterophoric patients.

  16. The effect of lens-induced anisometropia on accommodation and vergence during human visual development.

    PubMed

    Bharadwaj, Shrikant R; Candy, T Rowan

    2011-06-01

    Clear and single binocular vision, a prerequisite for normal human visual development, is achieved through accommodation and vergence. Anisometropia is associated with abnormal visual development, but its impact on accommodation and vergence, and therefore on the individual's visual experience, is not known. This study determined the impact of transiently induced anisometropia on accommodative and vergence performance of the typically developing human visual system. One hundred eighteen subjects (age range, 2.9 months to 41.1 years) watched a cartoon movie that moved between 80 and 33 cm under six different viewing conditions: binocular and monocular, and with ±2 diopters (D) and ±4 D of lens-induced anisometropia. Twenty-one subjects (age range, 3.1 months to 12.1 years) also watched the movie with 11% induced aniseikonia. Accommodation and vergence were recorded in both eyes using a videoretinoscope (25 Hz). The main effect of viewing condition was statistically significant for both accommodation and vergence (both P < 0.001), with monocular accommodative and vergence gains statistically significantly smaller than the binocular and four induced anisometropia conditions (P < 0.001 for both accommodation and vergence). The main effect of age approached significance for accommodation (P = 0.06) and was not significant for vergence (P = 0.32). Accommodative and vergence gains with induced aniseikonia were not statistically significantly different from the binocular condition (both P > 0.5). Accommodative and vergence gains of the typically developing visual system deteriorated marginally (accommodation more than vergence) with transiently induced anisometropia (up to ±4 D) and did not deteriorate significantly with induced aniseikonia of 11%. Some binocular cues remained with ±4 D of induced anisometropia and 11% induced aniseikonia, as indicated by the accommodative and vergence gains being higher than in monocular viewing.

  17. The Effect of Lens-Induced Anisometropia on Accommodation and Vergence during Human Visual Development

    PubMed Central

    Candy, T. Rowan

    2011-01-01

    Purpose. Clear and single binocular vision, a prerequisite for normal human visual development, is achieved through accommodation and vergence. Anisometropia is associated with abnormal visual development, but its impact on accommodation and vergence, and therefore on the individual's visual experience, is not known. This study determined the impact of transiently induced anisometropia on accommodative and vergence performance of the typically developing human visual system. Methods. One hundred eighteen subjects (age range, 2.9 months to 41.1 years) watched a cartoon movie that moved between 80 and 33 cm under six different viewing conditions: binocular and monocular, and with ±2 diopters (D) and ±4 D of lens-induced anisometropia. Twenty-one subjects (age range, 3.1 months to 12.1 years) also watched the movie with 11% induced aniseikonia. Accommodation and vergence were recorded in both eyes using a videoretinoscope (25 Hz). Results. The main effect of viewing condition was statistically significant for both accommodation and vergence (both P < 0.001), with monocular accommodative and vergence gains statistically significantly smaller than the binocular and four induced anisometropia conditions (P < 0.001 for both accommodation and vergence). The main effect of age approached significance for accommodation (P = 0.06) and was not significant for vergence (P = 0.32). Accommodative and vergence gains with induced aniseikonia were not statistically significantly different from the binocular condition (both P > 0.5). Conclusions. Accommodative and vergence gains of the typically developing visual system deteriorated marginally (accommodation more than vergence) with transiently induced anisometropia (up to ±4 D) and did not deteriorate significantly with induced aniseikonia of 11%. Some binocular cues remained with ±4 D of induced anisometropia and 11% induced aniseikonia, as indicated by the accommodative and vergence gains being higher than in monocular viewing

  18. Reducing the lag of accommodation by auditory biofeedback: A pilot study.

    PubMed

    Wagner, Sandra; Ohlendorf, Arne; Schaeffel, Frank; Wahl, Siegfried

    2016-12-01

    The purpose of this study was to investigate whether a reduction of the accommodative lag is possible by training the accuracy of accommodation using auditory biofeedback. Accommodation responses were measured in thirty-one young adults with myopia for dioptric target distances of 2.0, 2.5, and 3.0D using an eccentric infrared photorefractor. For the biofeedback training, subjects were randomly assigned to an experimental (n=15) or a control group (n=16). Subjects of the experimental group were provided with two tones while fixating a target, one tone was related to their accommodative response and the second to the target distance. Their task was to match these tones. The control group did not receive any auditory biofeedback. Two different training methods were applied, a continuous training of 200s, and ten consecutive sessions of 20s each. The training effects on the lag of accommodation (change Δ) were highly variable. Regarding the entire study group, the observed change in the accommodative lag was greater at closer distances, while no difference between the two training methods was revealed. Nevertheless, seven experimental subjects reduced their lag by ⩾0.3D (3.0D target distance: Δ long =-0.29±0.20D, Δ short =-0.24±0.21D). This reduction was also seen in two control subjects. Remeasurement revealed that the average training effect cannot be preserved over a period of 5-7days. The current investigation has shown that the accuracy of accommodation can be trained in some subjects using auditory biofeedback for target distances of 2.5D or closer. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. 49 CFR 595.7 - Requirements for vehicle modifications to accommodate people with disabilities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... accommodate people with disabilities. 595.7 Section 595.7 Transportation Other Regulations Relating to... (CONTINUED) MAKE INOPERATIVE EXEMPTIONS Vehicle Modifications To Accommodate People With Disabilities § 595.7 Requirements for vehicle modifications to accommodate people with disabilities. (a) Any motor vehicle repair...

  20. Différenciation paléogéographique à l'Ordovicien supérieur dans le Tafilalt (Anti-Atlas oriental, Maroc) sous l'interaction de la glaciation et de la tectonique

    NASA Astrophysics Data System (ADS)

    El Maazouz, Brahim; Hamoumi, Naima

    2007-07-01

    The Tafilalt domain, which corresponded, during the Lower and Middle Ordovician, to a storm and/or tide-dominated epeiric shelf with east-west- to ENE-WSW-trending isopachs, such as the whole 'Anti-Atlasic basin', recorded major palaeogeographical changes during the Upper Ordovician. An extensional tectonic event resulted in the individualization of two sub-basins: the 'Khabt-El-Hejar sub-basin' and the 'western Tafilalt sub-basin', where new environments developed under the interplay between tectonics and glaciation. In the northeastern Tafilalt sub-basin took place an isolated carbonate platform, where Bryozoan mounds nucleated, and a mixed siliciclastic carbonate high-energy peritidal littoral. In the 'western Tafilalt sub-basin', the siliciclastic shelf was structured in half-graben, where sediments from the Saharan glacier and the carbonate platform of the Khabt-El-Hejar sub-basin accumulated in fan deltas.

  1. Workplace accommodations for employees with disabilities: A multilevel model of employer decision-making.

    PubMed

    Telwatte, Apsara; Anglim, Jeromy; Wynton, Sarah K A; Moulding, Richard

    2017-02-01

    Existing research suggests that the decision to grant or deny workplace accommodations for people with disabilities is influenced by a range of legal and nonlegal factors. However, less is known about how these factors operate at the within-person level. Thus, we proposed and tested a multilevel model of the accommodation decision-making process, which we applied to better understand why people with psychological disabilities often experience greater challenges in obtaining accommodations. A sample of 159 Australian adults, composed mostly of managers and HR professionals, read 12 vignettes involving requests for accommodations from existing employees. The requests differed in whether they were for psychological or physical disabilities. For each vignette, participants rated their empathy with the employee, the legitimacy of the employee's disability, the necessity for productivity, the perceived cost, and the reasonableness, and indicated whether they would grant the accommodation. Multilevel modeling indicated that greater empathy, legitimacy, and necessity, and lower perceived cost predicted perceptions of greater reasonableness and greater granting. Accommodation requests from employees with psychological disabilities were seen as less reasonable and were less likely to be granted; much of this effect seemed to be driven by perceptions that such accommodations were less necessary for productivity. Ratings on accommodations were influenced both by general between-person tendencies and within-person appraisals of particular scenarios. The study points to a need for organizations to more clearly establish guidelines for how decision-makers should fairly evaluate accommodation requests for employees with psychological disabilities and disability more broadly. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. Peripheral Design of Progressive Addition Lenses and the Lag of Accommodation in Myopes.

    PubMed

    Schilling, Tim; Ohlendorf, Arne; Varnas, Saulius R; Wahl, Siegfried

    2017-07-01

    Insufficient accommodative response is assumed to result in myopia progression. We have investigated if the accommodative lag in myopes is different between a single vision lens (SVL) and the progressive addition lens PAL 2, clinically trialled for its ability to reduce progression of myopia, and if there exist differences in accommodative lag between PAL 2 and other PALs with the same addition power (+1.50 D). The influence of spherical SVL and four different designs of PALs that differ in the near zone width (PAL 1) or that have different signs and magnitude of horizontal gradients of mean power adjacent to their near vision zones (PAL 3 and PAL 4) on the accommodative response was investigated for different near viewing distances (40, 33, and 25 cm) in 31 subjects, aged 18 to 25 years. The SVL correction resulted in insufficient accommodative response for the near object viewing distances tested. PAL 2 did significantly reduce accommodative lag for all near object distances tested. The PAL design with a more negative horizontal mean power gradient (PAL 4) provided a lower lag of accommodation when compared with PAL 2 at the shortest object distance of 25 cm (P = 0.03) and was able to reduce the lag of accommodation to a level below the depth of focus for the higher near working distances tested. Designs of PAL with more negative horizontal mean power gradients are the most effective in lowering the lag of accommodation in myopes. This could make them good test candidates for myopia control applications.

  3. OCT-based crystalline lens topography in accommodating eyes.

    PubMed

    Pérez-Merino, Pablo; Velasco-Ocana, Miriam; Martinez-Enriquez, Eduardo; Marcos, Susana

    2015-12-01

    Custom Spectral Domain Optical Coherence Tomography (SD-OCT) provided with automatic quantification and distortion correction algorithms was used to measure anterior and posterior crystalline lens surface elevation in accommodating eyes and to evaluate relationships between anterior segment surfaces. Nine young eyes were measured at different accommodative demands. Anterior and posterior lens radii of curvature decreased at a rate of 0.78 ± 0.18 and 0.13 ± 0.07 mm/D, anterior chamber depth decreased at 0.04 ± 0.01 mm/D and lens thickness increased at 0.04 ± 0.01 mm/D with accommodation. Three-dimensional surface elevations were estimated by subtracting best fitting spheres. In the relaxed state, the spherical term accounted for most of the surface irregularity in the anterior lens (47%) and astigmatism (70%) in the posterior lens. However, in accommodated lenses astigmatism was the predominant surface irregularity (90%) in the anterior lens. The RMS of high-order irregularities of the posterior lens surface was statistically significantly higher than that of the anterior lens surface (x2.02, p<0.0001). There was significant negative correlation in vertical coma (Z3 (-1)) and oblique trefoil (Z3 (-3)) between lens surfaces. The astigmatic angle showed high degree of alignment between corneal surfaces, moderate between corneal and anterior lens surface (~27 deg), but differed by ~80 deg between the anterior and posterior lens surfaces (including relative anterior/posterior lens astigmatic angle shifts (10-20 deg).

  4. OCT-based crystalline lens topography in accommodating eyes

    PubMed Central

    Pérez-Merino, Pablo; Velasco-Ocana, Miriam; Martinez-Enriquez, Eduardo; Marcos, Susana

    2015-01-01

    Custom Spectral Domain Optical Coherence Tomography (SD-OCT) provided with automatic quantification and distortion correction algorithms was used to measure anterior and posterior crystalline lens surface elevation in accommodating eyes and to evaluate relationships between anterior segment surfaces. Nine young eyes were measured at different accommodative demands. Anterior and posterior lens radii of curvature decreased at a rate of 0.78 ± 0.18 and 0.13 ± 0.07 mm/D, anterior chamber depth decreased at 0.04 ± 0.01 mm/D and lens thickness increased at 0.04 ± 0.01 mm/D with accommodation. Three-dimensional surface elevations were estimated by subtracting best fitting spheres. In the relaxed state, the spherical term accounted for most of the surface irregularity in the anterior lens (47%) and astigmatism (70%) in the posterior lens. However, in accommodated lenses astigmatism was the predominant surface irregularity (90%) in the anterior lens. The RMS of high-order irregularities of the posterior lens surface was statistically significantly higher than that of the anterior lens surface (x2.02, p<0.0001). There was significant negative correlation in vertical coma (Z3−1) and oblique trefoil (Z3−3) between lens surfaces. The astigmatic angle showed high degree of alignment between corneal surfaces, moderate between corneal and anterior lens surface (~27 deg), but differed by ~80 deg between the anterior and posterior lens surfaces (including relative anterior/posterior lens astigmatic angle shifts (10-20 deg). PMID:26713216

  5. Vergence analysis reveals the influence of axial distances on accommodation with age and axial ametropia.

    PubMed

    Davies, Leon N; Dunne, Mark C M; Gibson, George A; Wolffsohn, James S

    2010-07-01

    Despite numerous investigations, the aetiology and mechanism of accommodation and presbyopia remains equivocal. Using Gaussian first-order ray tracing calculations, we examine the contribution that ocular axial distances make to the accommodation response. Further, the influence of age and ametropia are also considered. The data show that all changes in axial distances during accommodation reduce the accommodation response, with the reduction in anterior chamber depth contributing most to this overall attenuation. Although the total power loss due to the changes in axial distances remained constant with increasing age, hyperopes exhibited less accommodation than myopes. The study, therefore, enhances our understanding of biometric accommodative changes and demonstrates the utility of vergence analysis in the assessment of accommodation.

  6. Regional Sign Language Varieties in Contact: Investigating Patterns of Accommodation

    ERIC Educational Resources Information Center

    Stamp, Rose; Schembri, Adam; Evans, Bronwen G.; Cormier, Kearsy

    2016-01-01

    Short-term linguistic accommodation has been observed in a number of spoken language studies. The first of its kind in sign language research, this study aims to investigate the effects of regional varieties in contact and lexical accommodation in British Sign Language (BSL). Twenty-five participants were recruited from Belfast, Glasgow,…

  7. Accommodative insufficiency in a student population in Iran.

    PubMed

    Hashemi, Hassan; Khabazkhoob, Mehdi; Nabovati, Payam; Shahraki, Fatemeh Azad; Ostadimoghaddam, Hadi; Faghihi, Mohammad; Aghamirsalim, Mohamadreza; Doostdar, Asgar; Yekta, Abbasali

    2018-05-22

    To determine the prevalence of accommodative insufficiency (AI) and its relation with age, gender, and refractive errors in a college-age student population in Iran. The present study was conducted cross-sectionally in 2017. All students had optometric tests including measurement of visual acuity, objective and subjective refraction, as well as binocular vision and accommodative examinations. Amplitude of accommodation was measured with the Donders' push-up method using the Royal Air Force (RAF) rule. Monocular accommodative facility was measured with ±2.00diopter flipper lenses. The accommodative response was tested using dynamic retinoscopy with the monocular estimation method (MEM). The prevalence of AI in the studied population was 4.07% (95% CI: 2.61-5.52). The rate was 6.04% (95% CI: 3.58-8.50) in females and 2.01% (95% CI: 0.53-3.48) in males, and logistic regression showed a significantly higher odds of AI in females (OR=3.14, 95% CI: 1.33-7.45, p-value=0.009). The prevalence of AI was 2.59% (95% CI: 0.55-7.56) in the 18-19-year-old age group and 4.08% (95% CI: 0.09-8.07) in the 24-25-year-old group (p-value=0.848). The prevalence of AI among emmetropic, myopic, and hyperopic individuals was 3.74% (95% CI: 1.88-5.61), 4.44% (95% CI: 2.07-6.81), and 5.26% (95% CI: 4.79-16.32), respectively (p-value=0.869). In the multiple regression model, only gender showed significant relationship with AI (Odds ratio=3.14, 95% CI: 1.33-7.45; p-values=0.009). The prevalence of AI in the present study is lower than the most prevalence rates reported in previous studies. In the present study, gender and AI showed a strong association, such that AI prevalence was significantly higher in females than males. Copyright © 2018 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

  8. Predicting Accommodative Response Using Paraxial Schematic Eye Models

    PubMed Central

    Ramasubramanian, Viswanathan; Glasser, Adrian

    2016-01-01

    Purpose Prior ultrasound biomicroscopy (UBM) studies showed that accommodative optical response (AOR) can be predicted from accommodative biometric changes in a young and a pre-presbyopic population from linear relationships between accommodative optical and biometric changes, with a standard deviation of less than 0.55D. Here, paraxial schematic eyes (SE) were constructed from measured accommodative ocular biometry parameters to see if predictions are improved. Methods Measured ocular biometry (OCT, A-scan and UBM) parameters from 24 young and 24 pre-presbyopic subjects were used to construct paraxial SEs for each individual subject (individual SEs) for three different lens equivalent refractive index methods. Refraction and AOR calculated from the individual SEs were compared with Grand Seiko (GS) autorefractor measured refraction and AOR. Refraction and AOR were also calculated from individual SEs constructed using the average population accommodative change in UBM measured parameters (average SEs). Results Schematic eye calculated and GS measured AOR were linearly related (young subjects: slope = 0.77; r2 = 0.86; pre-presbyopic subjects: slope = 0.64; r2 = 0.55). The mean difference in AOR (GS - individual SEs) for the young subjects was −0.27D and for the pre-presbyopic subjects was 0.33D. For individual SEs, the mean ± SD of the absolute differences in AOR between the GS and SEs was 0.50 ± 0.39D for the young subjects and 0.50 ± 0.37D for the pre-presbyopic subjects. For average SEs, the mean ± SD of the absolute differences in AOR between the GS and the SEs was 0.77 ± 0.88D for the young subjects and 0.51 ± 0.49D for the pre-presbyopic subjects. Conclusions Individual paraxial SEs predict AOR, on average, with a standard deviation of 0.50D in young and pre-presbyopic subject populations. Although this prediction is only marginally better than from individual linear regressions, it does consider all the ocular biometric parameters. PMID:27092928

  9. Receding and disparity cues aid relaxation of accommodation

    PubMed Central

    Horwood, Anna M; Riddell, Patricia M

    2015-01-01

    Purpose Accommodation can mask hyperopia and reduce the accuracy of non-cycloplegic refraction. It is therefore important to minimize accommodation to obtain as accurate a measure of hyperopia as possible. In order to characterize the parameters required to measure the maximally hyperopic error using photorefraction, we used different target types and distances to determine which target was most likely to maximally relax accommodation and thus more accurately detect hyperopia in an individual. Methods A PlusoptiX SO4 infra-red photorefractor was mounted in a remote haploscope which presented the targets. All participants were tested with targets at four fixation distances between 0.3m and 2m containing all combinations of blur, disparity and proximity/looming cues. 38 infants (6-44 wks) were studied longitudinally, and 104 children (4 -15 yrs (mean 6.4)) and 85 adults, with a range of refractive errors and binocular vision status, were tested once. Cycloplegic refraction data was available for a sub-set of 59 participants spread across the age range. Results The maximally hyperopic refraction (MHR) found at any time in the session was most frequently found when fixating the most distant targets and those containing disparity and dynamic proximity/looming cues. Presence or absence of blur was less significant, and targets in which only single cues to depth were present were also less likely to produce MHR. MHR correlated closely with cycloplegic refraction (r = 0.93,mean difference 0.07D,p=n.s.,95%CI ±<0.25D) after correction by a calibration factor. Conclusion Maximum relaxation of accommodation occurred for binocular targets receding into the distance. Proximal and disparity cues aid relaxation of accommodation to a greater extent than blur, and thus non-cycloplegic refraction targets should incorporate these cues. This is especially important in screening contexts with a brief opportunity to test for significant hyperopia. MHR in our laboratory was found to be a

  10. Comparison between carbachol iontophoresis and intravenous pilocarpine stimulated accommodation in anesthetized rhesus monkeys.

    PubMed

    Wendt, Mark; He, Lin; Glasser, Adrian

    2013-10-01

    Rhesus monkeys are an animal model for human accommodation and presbyopia and consistent and repeatable methods are needed to stimulate and measure accommodation in anesthetized rhesus monkeys. Accommodation has typically been pharmacologically stimulated with topical pilocarpine or carbachol iontophoresis. Intravenous (i.v.) pilocarpine has recently been shown to produce more natural, rapid and reproducible accommodative responses compared to topical pilocarpine. Here, i.v. pilocarpine was compared to carbachol iontophoresis stimulated accommodation. Experiments were performed under anaesthesia on five previously iridectomized monkeys aged 10-16 years. In three monkeys, accommodation was stimulated with carbachol iontophoresis in five successive experiments and refraction measured with a Hartinger coincidence refractometer. In separate experiments, accommodation was stimulated using a 5 mg/kg bolus of i.v. pilocarpine given over 30 s followed by a continuous infusion of 20 mg/kg/hr for 5.5 min in three successive experiments with the same monkeys as well as in single experiments with two additional monkeys. Refraction was measured continuously using photorefraction with baseline and accommodated refraction also measured with the Hartinger. In subsequent i.v. pilocarpine experiments with each monkey, accommodative changes in lens equatorial diameter were measured in real-time with video-image analysis. Maximum accommodation of three monkeys with carbachol iontophoresis (five repeats) was (mean ± SD; range) 14.0 ± 3.5; 9.9-20.3 D and with i.v. pilocarpine stimulation (three repeats) was 11.1 ± 1.1; 9.9-13.0 D. The average of the standard deviations of maximum accommodation from each monkey was 0.8 ± 0.3 D from carbachol iontophoresis and 0.3 ± 0.2 from i.v. pilocarpine. The average latency to the start of the response after carbachol iontophoresis was 2.5 ± 3.9; 0.0-12.0 min with a time constant of 12.7 ± 9.5; 2.3-29.2 min. The average

  11. Quantifying interactions between accommodation and vergence in a binocularly normal population.

    PubMed

    Sweeney, Laura E; Seidel, Dirk; Day, Mhairi; Gray, Lyle S

    2014-12-01

    Stimulation of the accommodation system results in a response in the vergence system via accommodative vergence cross-link interactions, and stimulation of the vergence system results in an accommodation response via vergence accommodation cross-link interactions. Cross-link interactions are necessary in order to ensure simultaneous responses in the accommodation and vergence systems. The crosslink interactions are represented most comprehensively by the response AC/A (accommodative vergence) and CA/C (vergence accommodation) ratios, although the stimulus AC/A ratio is measured clinically, and the stimulus CA/C ratio is seldom measured in clinical practice. The present study aims to quantify both stimulus and response AC/A and CA/C ratios in a binocularly normal population, and determine the relationship between them. 25 Subjects (mean ± SD age 21.0 ± 1.9 years) were recruited from the university population. A significant linear relationship was found between the stimulus and response ratios, for both AC/A (r² = 0.96, p < 0.001) and CA/C ratios (r² = 0.40, p < 0.05). Good agreement was found between the stimulus and response AC/A ratios (95% CI -0.06 to 0.24 MA/D). Stimulus and response CA/C ratios are linearly related. Stimulus CA/C ratios were higher than response ratios at low values, and lower than response ratios at high values (95% CI -0.46 to 0.42 D/MA). Agreement between stimulus and response CA/C ratios is poorer than that found for AC/A ratios due to increased variability in vergence responses when viewing the Gaussian blurred target. This study has shown that more work is needed to refine the methodology of CA/C ratio measurement.

  12. Magnitude of visual accommodation to a head-up display

    NASA Technical Reports Server (NTRS)

    Leitner, E. F.; Haines, R. F.

    1981-01-01

    The virtual image symbology of head-up displays (HUDs) is presented at optical infinity to the pilot. This design feature is intended to help pilots maintain visual focus distance at optical infinity. However, the accommodation response could be nearer than optical infinity, due to an individual's dark focus response. Accommodation responses were measured of two age groups of airline pilots to: (1) static symbology on a HUD; (2) a landing site background at optical infinity; (3) the combination of the HUD symbology and the landing site background; and (4) complete darkness. Results indicate that magnitude of accommodation to HUD symbology, with and without the background, is not significantly different from an infinity focus response for either age group. The dark focus response is significantly closer than optical infinity for the younger pilots, but not the older pilots, a finding consistent with previous research.

  13. Human eyes do not need monochromatic aberrations for dynamic accommodation.

    PubMed

    Bernal-Molina, Paula; Marín-Franch, Iván; Del Águila-Carrasco, Antonio J; Esteve-Taboada, Jose J; López-Gil, Norberto; Kruger, Philip B; Montés-Micó, Robert

    2017-09-01

    To determine if human accommodation uses the eye's own monochromatic aberrations to track dynamic accommodative stimuli. Wavefront aberrations were measured while subjects monocularly viewed a monochromatic Maltese cross moving sinusoidally around 2D of accommodative demand with 1D amplitude at 0.2 Hz. The amplitude and phase (delay) of the accommodation response were compared to the actual vergence of the stimulus to obtain gain and temporal phase, calculated from wavefront aberrations recorded over time during experimental trials. The tested conditions were as follows: Correction of all the subject's aberrations except defocus (C); Correction of all the subject's aberrations except defocus and habitual second-order astigmatism (AS); Correction of all the subject's aberrations except defocus and odd higher-order aberrations (HOAs); Correction of all the subject's aberrations except defocus and even HOAs (E); Natural aberrations of the subject's eye, i.e., the adaptive-optics system only corrected the optical system's aberrations (N); Correction of all the subject's aberrations except defocus and fourth-order spherical aberration (SA). The correction was performed at 20 Hz and each condition was repeated six times in randomised order. Average gain (±2 standard errors of the mean) varied little across conditions; between 0.55 ± 0.06 (SA), and 0.62 ± 0.06 (AS). Average phase (±2 standard errors of the mean) also varied little; between 0.41 ± 0.02 s (E), and 0.47 ± 0.02 s (O). After Bonferroni correction, no statistically significant differences in gain or phase were found in the presence of specific monochromatic aberrations or in their absence. These results show that the eye's monochromatic aberrations are not necessary for accommodation to track dynamic accommodative stimuli. © 2017 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.

  14. Workplace accommodations for persons with physical disabilities: evidence synthesis of the peer-reviewed literature.

    PubMed

    Padkapayeva, Kathy; Posen, Andrew; Yazdani, Amin; Buettgen, Alexis; Mahood, Quenby; Tompa, Emile

    2017-10-01

    To identify and synthesize research evidence on workplace accommodations used by employers to recruit, hire, retain, and promote persons with physical disabilities. A structured search of six electronic journal databases was undertaken to identify peer-reviewed literature on the topic published from January 1990 to March 2016. Articles describing or evaluating workplace disability accommodation policies and practices were given a full-text review. Topic experts were contacted to identify additional studies. Details on specific accommodations described in 117 articles were synthesized and organized into three groups comprised of a total of 12 categories. The majority of studies did not rigorously evaluate effectiveness or cost-effectiveness of the accommodations under study. This evidence synthesis provides an overview of the peer-reviewed literature of value to occupational rehabilitation professionals and employers seeking guidance on workplace accommodation policies and practices for persons with physical disabilities. A wide range of accommodation options is available for addressing physical, social, and attitudinal barriers to successful employment. Besides physical/technological modifications, accommodations to enhance workplace flexibility and worker autonomy and strategies to promote workplace inclusion and integration are important. More comprehensive reporting and evaluations of the effectiveness of accommodations in research literature are needed to develop best practices for accommodating persons with disabilities. Implications for rehabilitation There is a substantial peer-reviewed literature that provides insights into the barriers for persons with physical disabilities and the workplace accommodation practices to address them, though rigorous evaluations of effectiveness and cost-effectiveness are uncommon. Attitudinal and social barriers stemming from stereotypes, ignorance and lack of knowledge are as important as physical barriers to employment for

  15. 41 CFR 301-10.122 - What class of airline accommodations must I use?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false What class of airline accommodations must I use? 301-10.122 Section 301-10.122 Public Contracts and Property Management Federal Travel... Common Carrier Transportation Airline Accommodations § 301-10.122 What class of airline accommodations...

  16. Problems and accommodation strategies reported by computer users with rheumatoid arthritis or fibromyalgia.

    PubMed

    Baker, Nancy A; Rubinstein, Elaine N; Rogers, Joan C

    2012-09-01

    Little is known about the problems experienced by and the accommodation strategies used by computer users with rheumatoid arthritis (RA) or fibromyalgia (FM). This study (1) describes specific problems and accommodation strategies used by people with RA and FM during computer use; and (2) examines if there were significant differences in the problems and accommodation strategies between the different equipment items for each diagnosis. Subjects were recruited from the Arthritis Network Disease Registry. Respondents completed a self-report survey, the Computer Problems Survey. Data were analyzed descriptively (percentages; 95% confidence intervals). Differences in the number of problems and accommodation strategies were calculated using nonparametric tests (Friedman's test and Wilcoxon Signed Rank Test). Eighty-four percent of respondents reported at least one problem with at least one equipment item (RA = 81.5%; FM = 88.9%), with most respondents reporting problems with their chair. Respondents most commonly used timing accommodation strategies to cope with mouse and keyboard problems, personal accommodation strategies to cope with chair problems and environmental accommodation strategies to cope with monitor problems. The number of problems during computer use was substantial in our sample, and our respondents with RA and FM may not implement the most effective strategies to deal with their chair, keyboard, or mouse problems. This study suggests that workers with RA and FM might potentially benefit from education and interventions to assist with the development of accommodation strategies to reduce problems related to computer use.

  17. 28 CFR 41.53 - Reasonable accommodation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 1 2013-07-01 2013-07-01 false Reasonable accommodation. 41.53 Section 41.53 Judicial Administration DEPARTMENT OF JUSTICE IMPLEMENTATION OF EXECUTIVE ORDER 12250, NONDISCRIMINATION ON THE BASIS OF HANDICAP IN FEDERALLY ASSISTED PROGRAMS Guidelines for Determining Discriminatory...

  18. 28 CFR 41.53 - Reasonable accommodation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 1 2012-07-01 2012-07-01 false Reasonable accommodation. 41.53 Section 41.53 Judicial Administration DEPARTMENT OF JUSTICE IMPLEMENTATION OF EXECUTIVE ORDER 12250, NONDISCRIMINATION ON THE BASIS OF HANDICAP IN FEDERALLY ASSISTED PROGRAMS Guidelines for Determining Discriminatory...

  19. 28 CFR 41.53 - Reasonable accommodation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 1 2014-07-01 2014-07-01 false Reasonable accommodation. 41.53 Section 41.53 Judicial Administration DEPARTMENT OF JUSTICE IMPLEMENTATION OF EXECUTIVE ORDER 12250, NONDISCRIMINATION ON THE BASIS OF HANDICAP IN FEDERALLY ASSISTED PROGRAMS Guidelines for Determining Discriminatory...

  20. 28 CFR 41.53 - Reasonable accommodation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Reasonable accommodation. 41.53 Section 41.53 Judicial Administration DEPARTMENT OF JUSTICE IMPLEMENTATION OF EXECUTIVE ORDER 12250, NONDISCRIMINATION ON THE BASIS OF HANDICAP IN FEDERALLY ASSISTED PROGRAMS Guidelines for Determining Discriminatory...

  1. 28 CFR 41.53 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Reasonable accommodation. 41.53 Section 41.53 Judicial Administration DEPARTMENT OF JUSTICE IMPLEMENTATION OF EXECUTIVE ORDER 12250, NONDISCRIMINATION ON THE BASIS OF HANDICAP IN FEDERALLY ASSISTED PROGRAMS Guidelines for Determining Discriminatory...

  2. 45 CFR 605.12 - Reasonable accommodation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... to the known physical or mental limitations of an otherwise qualified handicapped applicant or... reasonable accommodation to the physical or mental limitations of the employee or applicant. [47 FR 8573, Mar...

  3. 45 CFR 605.12 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... to the known physical or mental limitations of an otherwise qualified handicapped applicant or... reasonable accommodation to the physical or mental limitations of the employee or applicant. [47 FR 8573, Mar...

  4. 45 CFR 605.12 - Reasonable accommodation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... to the known physical or mental limitations of an otherwise qualified handicapped applicant or... reasonable accommodation to the physical or mental limitations of the employee or applicant. [47 FR 8573, Mar...

  5. 45 CFR 605.12 - Reasonable accommodation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... to the known physical or mental limitations of an otherwise qualified handicapped applicant or... reasonable accommodation to the physical or mental limitations of the employee or applicant. [47 FR 8573, Mar...

  6. 45 CFR 605.12 - Reasonable accommodation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... to the known physical or mental limitations of an otherwise qualified handicapped applicant or... reasonable accommodation to the physical or mental limitations of the employee or applicant. [47 FR 8573, Mar...

  7. [One-year longitudinal change in parameters of myopic school children trained by a new accommodative training device--uncorrected visual acuity, refraction, axial length, accommodation, and pupil reaction].

    PubMed

    Watanabe, Kumiko; Hara, Naoto; Kimijima, Masumi; Kotegawa, Yasue; Ohno, Koji; Arimoto, Ako; Mukuno, Kazuo; Hisahara, Satoru; Horie, Hidenori

    2012-10-01

    School children with myopia were trained using a visual stimulation device that generated an isolated blur stimulus on a visual target, with a constant retinal image size and constant brightness. Uncorrected visual acuity, cycloplegic refraction, axial length, dynamic accommodation and papillary reaction were measured to investigate the effectiveness of the training. There were 45 school children with myopia without any other ophthalmic diseases. The mean age of the children was 8.9 +/- 2.0 years (age range; 6-16)and the mean refraction was -1.56 +/- 0.58 D (mean +/- standard deviation). As a visual stimulus, a white ring on a black background with a constant ratio of visual target size to retinal image size, irrespective of the distance, was displayed on a liquid crystal display (LCD), and the LCD was quickly moved from a proximal to a distal position to produce an isolated blur stimulus. Training with this visual stimulus was carried out in the relaxation phase of accommodation. Uncorrected visual acuity, cycloplegic refraction, axial length, dynamic accommodation and pupillary reaction were investigated before training and every 3 months during the training. Of the 45 subjects, 42 (93%) could be trained for 3 consecutive months, 33 (73%) for 6 months, 23 (51%) for 9 months, and 21 (47%) for 12 months. The mean refraction decreased by 0.83 +/- 0.56 D (mean +/- standard deviation) and the mean axial length increased by 0.47 +/- 0.16 mm at 1 year, showing that the training bad some effect in improving the visual acuity. In the tests of the dynamic accommodative responses, the latency of the accommodative-phase decreased from 0.4 +/- 0.2 sec to 0.3 +/- 0.1 sec at 1 year, the gain of the accommodative-phase improved from 69.0 +/- 27.0% to 93.3 +/- 13.4%, the maximum speed of the accommodative-phase increased from 5.1 +/- 2.2 D/sec to 6.8 +/- 2.2 D/sec and the gain of the relaxation-phase significantly improved from 52.1 +/- 26.0% to 72.7 +/- 13.7% (corresponding t

  8. [Magnetic resonance imaging study of effects of accommodation on human lens morphological characters].

    PubMed

    Zheng, Sui-lian; Zhang, Ai; Shi, Jian-jing; Zhou, Yun-xin

    2013-11-05

    To evaluate the effects of accommodation on lens morphological characters. From January 2011 to June 2011, magnetic resonance images of eyes were acquired from 30 subjects aged 20 to 24 years during accommodation and at rest. The optimal images were analyzed by Autocad 2010 to obtain the total lens cross-sectional area (CSA) and CSA of anterior and posterior portions of lens, anterior chamber depth, lens thickness, lens diameter, vitreous chamber depth and axial length during accommodation and at rest. Paired-t test was performed. The anterior curvature radius (mm), posterior curvature radius (mm), CSA of anterior portion (mm(2)), CSA of posterior portion (mm(2)), total lens CSA (mm(2)) was (8.7 ± 0.8), (6.2 ± 0.5), (7.5 ± 2.1), (12.0 ± 2.6), (20 ± 4) during relaxed accommodation; anterior curvature radius (mm), posterior curvature radius (mm), CSA of anterior portion (mm(2)), CSA of posterior portion (mm(2)), total lens CSA (mm(2)) was (7.1 ± 1.3), (5.6 ± 0.5), (14.7 ± 2.9), (12.2 ± 2.1) and (27 ± 4) during accommodation. The total lens CSA (t = -11.556, P < 0.01) and CSA of anterior portion (t = -15.653, P < 0.01) both increased in accommodative states. The CSA of posterior portion of lens (t = -0.437, P > 0.05) under a statistically independent accommodative state. There was significant difference in the anterior chamber depth (t = 4.366, P < 0.01), lens thickness (t = -5.456, P < 0.01) and lens diameter (t = 4.597, P < 0.01) in accommodative states. There were insignificant differences both in vitreous chamber depth (t = 0.428, P > 0.05) and axial length (t = 0.418, P > 0.05) under accommodative states. During accommodation, the anterior chamber depth decreases, lens thickness increases and diameter of lens decreases while anterior portions and total lens CSA increase. There are insignificant changes in posterior portions of lens CSA, vitreous chamber depth and axial length. The accommodative changes in CSA indicate that the anterior portion of lens

  9. Cues for the control of ocular accommodation and vergence during postnatal human development.

    PubMed

    Bharadwaj, Shrikant R; Candy, T Rowan

    2008-12-22

    Accommodation and vergence help maintain single and focused visual experience while an object moves in depth. The relative importance of retinal blur and disparity, the primary sensory cues to accommodation and vergence, is largely unknown during development; a period when growth of the eye and head necessitate continual recalibration of egocentric space. Here we measured the developmental importance of retinal disparity in 192 typically developing subjects (1.9 months to 46 years). Subjects viewed high-contrast cartoon targets with naturalistic spatial frequency spectra while their accommodation and vergence responses were measured from both eyes using a PowerRefractor. Accommodative gain was reduced during monocular viewing relative to full binocular viewing, even though the fixating eye generated comparable tracking eye movements in the two conditions. This result was consistent across three forms of monocular occlusion. The accommodative gain was lowest in infants and only reached adult levels by 7 to 10 years of age. As expected, the gain of vergence was also reduced in monocular conditions. When 4- to 6-year-old children read 20/40-sized letters, their monocular accommodative gain reached adult-like levels. In summary, binocular viewing appears necessary under naturalistic viewing conditions to generate full accommodation and vergence responses in typically developing humans.

  10. Cues for the control of ocular accommodation and vergence during postnatal human development

    PubMed Central

    Bharadwaj, Shrikant R.; Candy, T. Rowan

    2009-01-01

    Accommodation and vergence help maintain single and focused visual experience while an object moves in depth. The relative importance of retinal blur and disparity, the primary sensory cues to accommodation and vergence, is largely unknown during development; a period when growth of the eye and head necessitate continual recalibration of egocentric space. Here we measured the developmental importance of retinal disparity in 192 typically developing subjects (1.9 months to 46 years). Subjects viewed high-contrast cartoon targets with naturalistic spatial frequency spectra while their accommodation and vergence responses were measured from both eyes using a PowerRefractor. Accommodative gain was reduced during monocular viewing relative to full binocular viewing, even though the fixating eye generated comparable tracking eye movements in the two conditions. This result was consistent across three forms of monocular occlusion. The accommodative gain was lowest in infants and only reached adult levels by 7 to 10 years of age. As expected, the gain of vergence was also reduced in monocular conditions. When 4- to 6-year-old children read 20/40-sized letters, their monocular accommodative gain reached adult-like levels. In summary, binocular viewing appears necessary under naturalistic viewing conditions to generate full accommodation and vergence responses in typically developing humans. PMID:19146280

  11. On-the-Job Productivity Losses Among Employees With Health Problems: The Role of Work Accommodations.

    PubMed

    Gifford, Brian; Zong, Yang

    2017-09-01

    Debates about the productivity impact of work accommodations typically focus on employment and labor force participation outcomes. This study considers whether accommodations mediate on-the-job productivity losses among employees who report health problems. The study uses ordered logistic regression to predict employees' self-reported productivity losses as a function of health problems and experiences with needed work accommodations. On average, the odds that an employee who did not get a needed accommodation reported higher levels of lost productivity are 5.11 times the odds for an employee who got a needed accommodation. Although health problems make it difficult for many employees to perform well on the job, accommodations could reduce productivity losses in some cases. Nonetheless, more research on the impact of specific kinds of accommodations for different chronic conditions is warranted.

  12. Holocene reef development where wave energy reduces accommodation

    USGS Publications Warehouse

    Grossman, Eric E.; Fletcher, Charles H.

    2004-01-01

    Analyses of 32 drill cores obtained from the windward reef of Kailua Bay, Oahu, Hawaii, indicate that high wave energy significantly reduced accommodation space for reef development in the Holocene and produced variable architecture because of the combined influence of sea-level history and wave exposure over a complex antecedent topography. A paleostream valley within the late Pleistocene insular limestone shelf provided accommodation space for more than 11 m of vertical accretion since sea level flooded the bay 8000 yr BP. Virtually no net accretion (pile-up of fore-reef-derived rubble (rudstone) and sparse bindstone, and (3) a final stage of catch-up bindstone accretion in depths > 6 m. Coral framestone accreted at rates of 2.5-6.0 mm/yr in water depths > 11 m during the early Holocene; it abruptly terminated at ~4500 yr BP because of wave scour as sea level stabilized. More than 4 m of rudstone derived from the upper fore reef accreted at depths of 6 to 13 m below sea level between 4000 and 1500 yr BP coincident with late Holocene relative sea-level fall. Variations in the thickness, composition, and age of these reef facies across spatial scales of 10-1000 m within Kailua Bay illustrate the importance of antecedent topography and wave-related stress in reducing accommodation space for reef development set by sea level. Although accommodation space of 6 to 17 m has existed through most of the Holocene, the Kailua reef has been unable to catch up to sea level because of persistent high wave stress.

  13. Application of video-based technology for the simultaneous measurement of accommodation and vergence.

    PubMed

    Suryakumar, Rajaraman; Meyers, Jason P; Irving, Elizabeth L; Bobier, William R

    2007-01-01

    Accommodation and vergence are two ocular motor systems that interact during binocular vision. Independent measurement of the response dynamics of each system has been achieved by the application of optometers and eye trackers. However, relatively few devices, typically earlier model optometers, allow the simultaneous assessment of accommodation and vergence. In this study we describe the development and application of a custom designed high-speed digital photorefractor that allows for rapid measures of accommodation (up to 75Hz). In addition the photorefractor was also synchronized with a video-based stereo eye tracker to allow a simultaneous measurement of accommodation and vergence. Analysis of accommodation and vergence could then be conducted offline. The new instrumentation is suitable for investigation of young children and could be potentially used for clinical populations.

  14. 34 CFR 104.12 - Reasonable accommodation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Education Regulations of the Offices of the Department of Education OFFICE FOR CIVIL RIGHTS, DEPARTMENT OF EDUCATION NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL... accommodation to the known physical or mental limitations of an otherwise qualified handicapped applicant or...

  15. 34 CFR 104.12 - Reasonable accommodation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Education Regulations of the Offices of the Department of Education OFFICE FOR CIVIL RIGHTS, DEPARTMENT OF EDUCATION NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL... accommodation to the known physical or mental limitations of an otherwise qualified handicapped applicant or...

  16. 34 CFR 104.12 - Reasonable accommodation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Education Regulations of the Offices of the Department of Education OFFICE FOR CIVIL RIGHTS, DEPARTMENT OF EDUCATION NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL... accommodation to the known physical or mental limitations of an otherwise qualified handicapped applicant or...

  17. 34 CFR 104.12 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Education Regulations of the Offices of the Department of Education OFFICE FOR CIVIL RIGHTS, DEPARTMENT OF EDUCATION NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL... accommodation to the known physical or mental limitations of an otherwise qualified handicapped applicant or...

  18. 34 CFR 104.12 - Reasonable accommodation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Education Regulations of the Offices of the Department of Education OFFICE FOR CIVIL RIGHTS, DEPARTMENT OF EDUCATION NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL... accommodation to the known physical or mental limitations of an otherwise qualified handicapped applicant or...

  19. Symptomatic accommodative and binocular dysfunctions from the use of flat-panel displays

    PubMed Central

    Porcar, Esteban; Montalt, Juan Carlos; Pons, Álvaro M.; España-Gregori, Enrique

    2018-01-01

    AIM To determine the presence of symptomatic accommodative and non-strabismic binocular dysfunctions (ANSBD) in a non-presbyopic population of video display unit (VDU) users with flat-panel displays. METHODS One hundred and one VDU users, aged between 20 to 34y, initially participated in the study. This study excluded contact-lens wearers and subjects who had undergone refractive surgery or had any systemic or ocular disease. First, subjects were asked about the type and nature of eye symptoms they experienced during VDU use. Then, a thorough eye examination excluded those subjects with a significant uncorrected refractive error or other problem, such as ocular motility disorders, vertical deviation, strabismus and eye diseases. Finally, the remaining participants underwent an exhaustive assessment of their accommodative and binocular vision status. RESULTS Eighty-nine VDU users (46 females and 43 males) were included in this study. They used flat-panel displays for an average of 5±1.9h a day. Twenty subjects presented ANSBD (22.5%). Convergence excess was the most frequent non-strabismic binocular dysfunction (9 subjects), followed by fusional vergence dysfunction (3 subjects) and convergence insufficiency (2 subjects). Within the accommodative dysfunctions, accommodative excess was the most common (4 subjects), followed by accommodative insufficiency (2 subjects). Moderate to severe eye symptoms were found in 13 subjects with ANSBD. CONCLUSION Significant eye symptoms in VDU users with accommodative and/or non-strabismic binocular dysfunctions often occur and should not be underestimated; therefore, an appropriate evaluation of accommodative and binocular vision status is more important for this population. PMID:29600186

  20. Magnetic resonance imaging of aging, accommodating, phakic, and pseudophakic ciliary muscle diameters

    PubMed Central

    Strenk, Susan A.; Strenk, Lawrence M.; Guo, Suqin

    2012-01-01

    PURPOSE To quantify in vivo accommodative changes in the aging human ciliary muscle diameter in phakic and pseudophakic eyes. SETTING Department of Surgery/Bioengineering, UMDNJ–Robert Wood Johnson Medical School, Piscataway, and the Institute of Ophthalmology and Visual Science UMDNJ–New Jersey Medical School, Newark, New Jersey, USA. METHODS Images were acquired from 48 eyes of 40 people between the ages of 22 and 91 years, 1 eye of 32 phakic volunteers and both eyes of 8 patients who had monocular implantation of a single-piece AcrySof intraocular lens (IOL) (Alcon Laboratories). Images were acquired during physiological accommodation and with accommodation at rest, and the diameter of the ciliary muscle ring was measured. RESULTS Results show the ciliary muscle remains active throughout life. The accommodative change in its diameter (mean 0.64 mm) (P<.00001) was undiminished by age or IOL implantation. Preliminary data showed that the accommodative decrease in muscle diameter in phakic and pseudophakic eyes was statistically identical. The phakic eyes had a marked decrease in ciliary muscle diameter with advancing age for both accommodative states (P<.000001 and P<.000001), which did not appear to be altered by IOL implantation. The lens equator was constant with age in the unaccommodated human eye, resulting in decreased circumlental space with advancing age in the phakic eyes. CONCLUSION Although the undiminished ability of the ciliary muscle to decrease its diameter with accommodation can be relied on in strategies for presbyopia correction, even in advanced presbyopia, the decreasing circumlental space and its potential effects on zonular tension must also be considered. PMID:17081859

  1. Changes in accommodation and ocular aberration with simultaneous vision multifocal contact lenses.

    PubMed

    Ruiz-Alcocer, Javier; Madrid-Costa, David; Radhakrishnan, Hema; Ferrer-Blasco, Teresa; Montés-Micó, Robert

    2012-09-01

    The aim of this study was to evaluate ocular aberration changes through different simultaneous vision multifocal contact lenses (CLs). Eighteen young-adult subjects with a mean age of 29.8±2.11 years took part. Changes in accommodative response, spherical aberration (C(4)(0)), horizontal coma (C(3)(1)), vertical coma (C(3)(-1)), and root mean square (RMS) of higher-order aberrations (HOAs, third to sixth orders) were evaluated. Measurements were obtained with a distance-single vision CL and 2 aspheric multifocal CLs of simultaneous focus center-near design (PureVision Low Add and PureVision High Add) for 2 accommodative stimuli (-2.50 and -4.00 D). All measurements were performed monocularly with a Hartmann-Shack aberrometer (IRX-3; Imagine Eyes, Orsay, France). No statistically significant differences were found in accommodative responses to -2.50- and -4.00-D stimuli between the single vision CL and the 2 multifocal CLs. Spherical aberration was found to decrease and become more negative with accommodation for both stimuli with all three CLs. Horizontal coma decreased significantly with accommodation (-2.5- and -4.00-D stimuli) for the distance-single vision CLs (P=0.002 and P=0.003). No differences were found in vertical coma Zernike coefficients. The RMS of HOAs was found to decrease only with the single vision CLs for both stimuli (P<0.01). Data obtained in this study suggest that in young subjects, the multifocal CLs studied do not induce large changes in accommodative response compared with the distance-single vision CLs. Spherical aberration reduced significantly with accommodation.

  2. 13 CFR 113.3-2 - Accommodations to religious observance and practice.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... NONDISCRIMINATION IN FINANCIAL ASSISTANCE PROGRAMS OF SBA-EFFECTUATION OF POLICIES OF FEDERAL GOVERNMENT AND SBA... financial assistance must accommodate to the religious observances and practices of an employee or... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Accommodations to religious...

  3. Patterns in workplace accommodations for people with multiple sclerosis to overcome cognitive and other disease-related limitations.

    PubMed

    Leslie, Mykal; Kinyanjui, Benson; Bishop, Malachy; Rumrill, Phillip D; Roessler, Richard T

    2015-01-01

    Cognitive symptoms and other functional limitations associated with multiple sclerosis (MS) have a significant negative impact on employment status. Work accommodations positively impact the ability of a person with MS to obtain and retain employment, however, current understanding of the role of accommodations in the careers of adults with MS is limited. To analyze the percentage of American workers with MS who utilize workplace accommodations as per Title I of the ADA, the types of accommodations most frequently required, and differences in disease variables, job-related factors, and quality of life between workers using and not using work accommodations. Data from 746 employed adult members of the National MS Society surveyed about career concerns were analyzed. Descriptive and inferential statistics were used as appropriate to address the research questions. Approximately 25% reported having requested accommodations, and 87.7% reported receiving the requested accommodation. Participants with progressive MS, cognitive impairment, higher number of MS symptoms and greater symptom severity were more likely to use work accommodations. Participants with accommodations reported poorer job match and career optimism than those using no accommodations. This large-scale analysis addresses several outstanding questions concerning work accommodations among workers with MS. Cognitive symptoms and disease severity are strongly associated with need for accommodations, however accommodations do not appear to promote job satisfaction or longevity. The accommodation request process and the impact of accommodations on employment retention remain important research foci.

  4. 50 CFR 260.101 - Lavatory accommodations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Fishery Products for Human Consumption Requirements for Plants Operating Under Continuous Inspection on A... water, soap, and single service towels, shall be provided. Such accommodations shall be in or near... which provides an adequate flow of water for washing hands. (d) Durable signs shall be posted...

  5. 50 CFR 260.101 - Lavatory accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Fishery Products for Human Consumption Requirements for Plants Operating Under Continuous Inspection on A... water, soap, and single service towels, shall be provided. Such accommodations shall be in or near... which provides an adequate flow of water for washing hands. (d) Durable signs shall be posted...

  6. 22 CFR 142.12 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., acquisition or modification of equipment or devices, the provision of readers or interpreters, and other... facilities, and size of budget; (2) Job restructuring, part-time or modified work schedules, acquisition and... sign language, when appropriate. (3) The nature and cost of the accommodation needed. (d) A recipient...

  7. 45 CFR 1170.22 - Reasonable accommodation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 3 2011-10-01 2011-10-01 false Reasonable accommodation. 1170.22 Section 1170.22 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL FOUNDATION ON THE ARTS AND THE HUMANITIES NATIONAL ENDOWMENT FOR THE HUMANITIES NONDISCRIMINATION ON THE BASIS OF HANDICAP IN FEDERALLY...

  8. 45 CFR 1170.22 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Reasonable accommodation. 1170.22 Section 1170.22 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL FOUNDATION ON THE ARTS AND THE HUMANITIES NATIONAL ENDOWMENT FOR THE HUMANITIES NONDISCRIMINATION ON THE BASIS OF HANDICAP IN FEDERALLY...

  9. 24 CFR 100.204 - Reasonable accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HOUSING DISCRIMINATORY CONDUCT UNDER THE FAIR HOUSING ACT Prohibition Against Discrimination Because of Handicap § 100.204 Reasonable accommodations. (a) It shall be unlawful for any person to refuse to make... necessary to afford a handicapped person equal opportunity to use and enjoy a dwelling unit, including...

  10. 24 CFR 100.204 - Reasonable accommodations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... HOUSING DISCRIMINATORY CONDUCT UNDER THE FAIR HOUSING ACT Prohibition Against Discrimination Because of Handicap § 100.204 Reasonable accommodations. (a) It shall be unlawful for any person to refuse to make... necessary to afford a handicapped person equal opportunity to use and enjoy a dwelling unit, including...

  11. 24 CFR 100.204 - Reasonable accommodations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... HOUSING DISCRIMINATORY CONDUCT UNDER THE FAIR HOUSING ACT Prohibition Against Discrimination Because of Handicap § 100.204 Reasonable accommodations. (a) It shall be unlawful for any person to refuse to make... necessary to afford a handicapped person equal opportunity to use and enjoy a dwelling unit, including...

  12. 24 CFR 100.204 - Reasonable accommodations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... HOUSING DISCRIMINATORY CONDUCT UNDER THE FAIR HOUSING ACT Prohibition Against Discrimination Because of Handicap § 100.204 Reasonable accommodations. (a) It shall be unlawful for any person to refuse to make... necessary to afford a handicapped person equal opportunity to use and enjoy a dwelling unit, including...

  13. 24 CFR 100.204 - Reasonable accommodations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... HOUSING DISCRIMINATORY CONDUCT UNDER THE FAIR HOUSING ACT Prohibition Against Discrimination Because of Handicap § 100.204 Reasonable accommodations. (a) It shall be unlawful for any person to refuse to make... necessary to afford a handicapped person equal opportunity to use and enjoy a dwelling unit, including...

  14. 29 CFR 32.13 - Reasonable accommodation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... physical or mental limitations of an otherwise qualified handicapped applicant, employee or participant... workforce, and duration and type of training; and (3) The nature and cost of the accommodation needed. (c) A... physical or mental limitations of the employee, applicant or participant. (d) Nothing in this paragraph...

  15. Manned Mars mission accommodation: Sprint mission

    NASA Technical Reports Server (NTRS)

    Cirillo, William M.; Kaszubowski, Martin J.; Ayers, J. Kirk; Llewellyn, Charles P.; Weidman, Deene J.; Meredith, Barry D.

    1988-01-01

    The results of a study conducted at the NASA-LaRC to assess the impacts on the Phase 2 Space Station of Accommodating a Manned Mission to Mars are documented. In addition, several candidate transportation node configurations are presented to accommodate the assembly and verification of the Mars Mission vehicles. This study includes an identification of a life science research program that would need to be completed, on-orbit, prior to mission departure and an assessment of the necessary orbital technology development and demonstration program needed to accomplish the mission. Also included is an analysis of the configuration mass properties and a preliminary analysis of the Space Station control system sizing that would be required to control the station. Results of the study indicate the Phase 2 Space Station can support a manned mission to Mars with the addition of a supporting infrastructure that includes a propellant depot, assembly hangar, and a heavy lift launch vehicle to support the large launch requirements.

  16. Correlates of accommodation of pediatric obsessive-compulsive disorder: parent, child, and family characteristics.

    PubMed

    Peris, Tara S; Bergman, R Lindsey; Langley, Audra; Chang, Susanna; McCracken, James T; Piacentini, John

    2008-10-01

    Pediatric obsessive-compulsive disorder (OCD) is a chronic, impairing condition associated with high levels of family accommodation (i.e., participation in symptoms). Understanding of factors that may engender accommodation of pediatric OCD is limited. This study conducted exploratory analyses of parent-, child-, and family-level correlates of family accommodation, considering both behavioral and affective components of the response. The sample included 65 youths (mean age 12.3 years, 62% male) with OCD and their parents who completed a standardized assessment battery composed of both clinical and self-report measures (e.g., Children's Yale-Brown Obsessive-Compulsive Scale, Brief Symptom Inventory). Family accommodation was common, with the provision of reassurance and participation in rituals the most frequent practices (occurring on a daily basis among 56% and 46% of parents, respectively). Total scores on the Family Accommodation Scale were not associated with child OCD symptom severity; however, parental involvement in rituals was associated with higher levels of child OCD severity and parental psychopathology and with lower levels of family organization. Comorbid externalizing symptomatology and family conflict were associated with parent report of worse consequences when not accommodating. Although these findings must be interpreted in light of potential type I error, they suggest that accommodation is the norm in pediatric OCD. Family-focused interventions must consider the parent, child, and family-level variables associated with this familial response when teaching disengagement strategies.

  17. Correlates of Accommodation of Pediatric Obsessive Compulsive Disorder: Parent, Child, and Family Characteristics

    PubMed Central

    Peris, Tara S.; Bergman, R. Lindsey; Langley, Audra; Chang, Susanna; McCracken, James T.; Piacentini, John

    2012-01-01

    Objective Pediatric obsessive-compulsive disorder (OCD) is a chronic, impairing condition associated with high levels of family accommodation (i.e., participation in symptoms). Understanding of factors that may engender accommodation of pediatric OCD is limited. This study conducted exploratory analyses of parent-, child-, and family-level correlates of family accommodation, considering both behavioral and affective components of the response. Method The sample included 65 youth (mean age = 12.3 years; 62% male) with OCD and their parents who completed a standardized assessment battery comprised of both clinical and self-report measures (e.g., CY-BOCS, Brief Symptom Inventory). Results Family accommodation was common, with the provision of reassurance and participation in rituals the most frequent practices (respectively occurring on a daily basis among 56% and 46% of parents). Total scores on the Family Accommodation Scale were not associated with child OCD symptom severity; however, parental involvement in rituals was associated with higher levels of child OCD severity and parental psychopathology, and with lower levels of family organization. Comorbid externalizing symptomatology and family conflict were associated with parent report of worse consequences when not accommodating. Conclusions Although these findings must be interpreted in light of potential Type I error, they suggest that accommodation is the norm in pediatric OCD. Family-focused interventions must consider the parent, child, and family-level variables associated with this familial response when teaching disengagement strategies. PMID:18724255

  18. Disentangling Mathematics Target and Access Skills: Implications for Accommodation Assignment Practices

    ERIC Educational Resources Information Center

    Ketterlin-Geller, Leanne R.; Jamgochian, Elisa M.; Nelson-Walker, Nancy J.; Geller, Joshua P.

    2012-01-01

    Appropriate assignment of accommodations is predicated on a clear distinction between target skills and access skills. In this study, we examine the agreement between test developer/researchers' and educators' classification of target and access skills as a possible explanatory mechanism for assigning accommodations. Findings indicate that…

  19. Exploring Barriers to College Student Use of Disability Services and Accommodations

    ERIC Educational Resources Information Center

    Marshak, Laura; Van Wieren, Todd; Ferrell, Dianne Raeke; Swiss, Lindsay; Dugan, Catherine

    2010-01-01

    Federal legislation requires most colleges and universities to provide equal access and reasonable accommodations for students with disabilities. However, many students do not fully avail themselves of college disability services and accommodations. It is important for Office of Disability Services (ODS) personnel to understand the reasons for…

  20. The relationship between refractive and biometric changes during Edinger–Westphal stimulated accommodation in rhesus monkeys

    PubMed Central

    Vilupuru, Abhiram S.; Glasser, Adrian

    2010-01-01

    Experiments were undertaken to understand the relationship between dynamic accommodative refractive and biometric (lens thickness (LT), anterior chamber depth (ACD) and anterior segment length (ASL=ACD+LT)) changes during Edinger–Westphal stimulated accommodation in rhesus monkeys. Experiments were conducted on three rhesus monkeys (aged 11·5, 4·75 and 4·75 years) which had undergone prior, bilateral, complete iridectomies and implantation of a stimulating electrode in the Edinger–Westphal (EW) nucleus. Accommodative refractive responses were first measured dynamically with video-based infrared photorefraction and then ocular biometric responses were measured dynamically with continuous ultrasound biometry (CUB) during EW stimulation. The same stimulus amplitudes were used for the refractive and biometric measurements to allow them to be compared. Main sequence relationships (ratio of peak velocity to amplitude) were calculated. Dynamic accommodative refractive changes are linearly correlated with the biometric changes and accommodative biometric changes in ACD, ASL and LT show systematic linear correlations with increasing accommodative amplitudes. The relationships are relatively similar for the eyes of the different monkeys. Dynamic analysis showed that main sequence relationships for both biometry and refraction are linear. Although accommodative refractive changes in the eye occur primarily due to changes in lens surface curvature, the refractive changes are well correlated with A-scan measured accommodative biometric changes. Accommodative changes in ACD, LT and ASL are all well correlated over the full extent of the accommodative response. PMID:15721617

  1. Accommodation and vergence response gains to different near cues characterize specific esotropias.

    PubMed

    Horwood, Anna M; Riddell, Patricia M

    2013-09-01

    To describe preliminary findings of how the profile of the use of blur, disparity, and proximal cues varies between non-strabismic groups and those with different types of esotropia. This was a case control study. A remote haploscopic photorefractor measured simultaneous convergence and accommodation to a range of targets containing all combinations of binocular disparity, blur, and proximal (looming) cues. Thirteen constant esotropes, 16 fully accommodative esotropes, and 8 convergence excess esotropes were compared with age- and refractive error-matched controls and 27 young adult emmetropic controls. All wore full refractive correction if not emmetropic. Response AC/A and CA/C ratios were also assessed. Cue use differed between the groups. Even esotropes with constant suppression and no binocular vision (BV) responded to disparity in cues. The constant esotropes with weak BV showed trends for more stable responses and better vergence and accommodation than those without any BV. The accommodative esotropes made less use of disparity cues to drive accommodation (p = 0.04) and more use of blur to drive vergence (p = 0.008) than controls. All esotropic groups failed to show the strong bias for better responses to disparity cues found in the controls, with convergence excess esotropes favoring blur cues. AC/A and CA/C ratios existed in an inverse relationship in the different groups. Accommodative lag of > 1.0 D at 33 cm was common (46%) in the pooled esotropia groups compared with 11% in typical children (p = 0.05). Esotropic children use near cues differently from matched non-esotropic children in ways characteristic to their deviations. Relatively higher weighting for blur cues was found in accommodative esotropia compared to matched controls.

  2. Accommodation and vergence response gains to different near cues characterize specific esotropias

    PubMed Central

    Horwood, Anna M; Riddell, Patricia M

    2015-01-01

    Aim To describe preliminary findings of how the profile of the use of blur, disparity and proximal cues varies between non-strabismic groups and those with different types of esotropia. Design Case control study Methodology A remote haploscopic photorefractor measured simultaneous convergence and accommodation to a range of targets containing all combinations of binocular disparity, blur and proximal (looming) cues. 13 constant esotropes, 16 fully accommodative esotropes, and 8 convergence excess esotropes were compared with age and refractive error matched controls, and 27 young adult emmetropic controls. All wore full refractive correction if not emmetropic. Response AC/A and CA/C ratios were also assessed. Results Cue use differed between the groups. Even esotropes with constant suppression and no binocular vision (BV) responded to disparity in cues. The constant esotropes with weak BV showed trends for more stable responses and better vergence and accommodation than those without any BV. The accommodative esotropes made less use of disparity cues to drive accommodation (p=0.04) and more use of blur to drive vergence (p=0.008) than controls. All esotropic groups failed to show the strong bias for better responses to disparity cues found in the controls, with convergence excess esotropes favoring blur cues. AC/A and CA/C ratios existed in an inverse relationship in the different groups. Accommodative lag of >1.0D at 33cm was common (46%) in the pooled esotropia groups compared with 11% in typical children (p=0.05). Conclusion Esotropic children use near cues differently from matched non-esotropic children in ways characteristic to their deviations. Relatively higher weighting for blur cues was found in accommodative esotropia compared to matched controls. PMID:23978142

  3. Testing Accommodations for Students with Disabilities.

    ERIC Educational Resources Information Center

    Florida State Dept. of Education, Tallahassee. Bureau of Instructional Support and Community Services.

    This brief guide explains the use of testing accommodations for students with a disability participating in state or district educational assessments under federal and Florida state law. These include the Individuals with Disabilities Education Act of 1997, Section 504 of the Rehabilitation Act, and the Florida Administrative Code. Planning…

  4. Accommodation response measurements for integral 3D image

    NASA Astrophysics Data System (ADS)

    Hiura, H.; Mishina, T.; Arai, J.; Iwadate, Y.

    2014-03-01

    We measured accommodation responses under integral photography (IP), binocular stereoscopic, and real object display conditions, and viewing conditions of binocular and monocular viewing conditions. The equipment we used was an optometric device and a 3D display. We developed the 3D display for IP and binocular stereoscopic images that comprises a high-resolution liquid crystal display (LCD) and a high-density lens array. The LCD has a resolution of 468 dpi and a diagonal size of 4.8 inches. The high-density lens array comprises 106 x 69 micro lenses that have a focal length of 3 mm and diameter of 1 mm. The lenses are arranged in a honeycomb pattern. The 3D display was positioned 60 cm from an observer under IP and binocular stereoscopic display conditions. The target was presented at eight depth positions relative to the 3D display: 15, 10, and 5 cm in front of the 3D display, on the 3D display panel, and 5, 10, 15 and 30 cm behind the 3D display under the IP and binocular stereoscopic display conditions. Under the real object display condition, the target was displayed on the 3D display panel, and the 3D display was placed at the eight positions. The results suggest that the IP image induced more natural accommodation responses compared to the binocular stereoscopic image. The accommodation responses of the IP image were weaker than those of a real object; however, they showed a similar tendency with those of the real object under the two viewing conditions. Therefore, IP can induce accommodation to the depth positions of 3D images.

  5. Eye-lens accommodation load and static trapezius muscle activity.

    PubMed

    Richter, H O; Bänziger, T; Forsman, M

    2011-01-01

    The purpose of this experimental study was to investigate if sustained periods of oculomotor load impacts on neck/scapular area muscle activity. The static trapezius muscle activity was assessed from bipolar surface electromyography, normalized to a submaximal contraction. Twenty-eight subjects with a mean age of 29 (range 19-42, SD 8) viewed a high-contrast fixation target for two 5-min periods through: (1) -3.5 dioptre (D) lenses; and (2) 0 D lenses. The target was placed 5 D away from the individual's near point of accommodation. Each subject's ability to compensate for the added blur was extracted via infrared photorefraction measurements. Subjects whose accommodative response was higher in the -D blur condition (1) showed relatively more static bilateral trapezius muscle activity level. During no blur (2) there were no signs of relationships. The results indicate that sustained eye-lens accommodation at near, during ergonomically unfavourable viewing conditions, could possibly represent a risk factor for trapezius muscle myalgia.

  6. The causes of covariation between C and O isotopes in the inorganic carbonate record

    NASA Astrophysics Data System (ADS)

    Swart, Peter; Oehlert, Amanda

    2017-04-01

    The δ13C values of carbonate rocks are widely used as proxies for understanding the global carbon cycle. While most workers would prefer to use δ13C values measured in oceanic sediments, during older times the only records that exist are those found in sediments deposited in epeiric seas or on continental margins and carbonate platforms. However, such records are often compromised by near surface diagenesis and therefore care must be taken to exclude altered records. One approach, which has been widely applied, has been to examine the covariation between δ13C and δ18O values, where a positive covariation has been suggested to indicate alteration. In order to test this assumption we present data from a core taken in the Bahamas that has been unequivocally subjected to both freshwater and marine diagenetic processes. Our data suggest that the majority of the zone which has been altered by freshwater shows no correlation between δ13C and δ18O values, with small intervals associated with sub-aerial exposure exhibiting inverse correlations, and only the upper partially altered portion of the core exhibiting positive relationships. The zone below the region of freshwater alteration, previously interpreted as being the mixing-zone, is characterized by a strong covariation between δ13C and δ18O values as a result of the upper portion of this zone having been affected by fresh water diagenesis compared to the lower portion. Within the marine influenced realm a variety of relationships are produced as a result of differences in sediment origin and diagenesis. For example, non-depositional surfaces, where marine diagenetic processes are maximized, are typically expressed by sharp positive correlations between δ13C and δ18O values, while changes related to different sediment sources are expressed as weak positive covariations. While the data set presented here may not be applicable in every situation, the study certainly emphasizes that care must be taken when rules

  7. Accommodation Responds to Optical Vergence and Not Defocus Blur Alone.

    PubMed

    Del Águila-Carrasco, Antonio J; Marín-Franch, Iván; Bernal-Molina, Paula; Esteve-Taboada, José J; Kruger, Philip B; Montés-Micó, Robert; López-Gil, Norberto

    2017-03-01

    To determine whether changes in wavefront spherical curvature (optical vergence) are a directional cue for accommodation. Nine subjects participated in this experiment. The accommodation response to a monochromatic target was measured continuously with a custom-made adaptive optics system while astigmatism and higher-order aberrations were corrected in real time. There were two experimental open-loop conditions: vergence-driven condition, where the deformable mirror provided sinusoidal changes in defocus at the retina between -1 and +1 diopters (D) at 0.2 Hz; and blur-driven condition, in which the level of defocus at the retina was always 0 D, but a sinusoidal defocus blur between -1 and +1 D at 0.2 Hz was simulated in the target. Right before the beginning of each trial, the target was moved to an accommodative demand of 2 D. Eight out of nine subjects showed sinusoidal responses for the vergence-driven condition but not for the blur-driven condition. Their average (±SD) gain for the vergence-driven condition was 0.50 (±0.28). For the blur-driven condition, average gain was much smaller at 0.07 (±0.03). The ninth subject showed little to no response for both conditions, with average gain <0.08. Vergence-driven condition gain was significantly different from blur-driven condition gain (P = 0.004). Accommodation responds to optical vergence, even without feedback, and not to changes in defocus blur alone. These results suggest the presence of a retinal mechanism that provides a directional cue for accommodation from optical vergence.

  8. Analysis and Countermeasures of Wind Power Accommodation by Aluminum Electrolysis Pot-Lines in China

    NASA Astrophysics Data System (ADS)

    Zhang, Hongliang; Ran, Ling; He, Guixiong; Wang, Zhenyu; Li, Jie

    2017-10-01

    The unit energy consumption and its price have become the main obstacles for the future development of the aluminum electrolysis industry in China. Meanwhile, wind power is widely being abandoned because of its instability. In this study, a novel idea for wind power accommodation is proposed to achieve a win-win situation: the idea is for nearby aluminum electrolysis plants to absorb the wind power. The features of the wind power distribution and aluminum electrolysis industry are first summarized, and the concept of wind power accommodation by the aluminum industry is introduced. Then, based on the characteristics of aluminum reduction cells, the key problems, including the bus-bar status, thermal balance, and magnetohydrodynamics instabilities, are analyzed. In addition, a whole accommodation implementation plan for wind power by aluminum reduction is introduced to explain the theoretical value of accommodation, evaluation of the reduction cells, and the industrial experiment scheme. A numerical simulation of a typical scenario proves that there is large accommodation potential for the aluminum reduction cells. Aluminum electrolysis can accommodate wind power and remain stable under the proper technique and accommodation scheme, which will provide promising benefits for the aluminum plant and the wind energy plant.

  9. Research of the aberrations of human eyes with accommodation based on eye model

    NASA Astrophysics Data System (ADS)

    Quan, Wei; Wang, Feng-lin; Wang, Zhao-qi

    2011-06-01

    The variation of the wavefront aberration with accommodation was investigated based on the eye model of Gullstrand-Le Grand. The anterior lens radius was optimized at different accommodation to focus the image at the retina, and the RMS and PV wave-front error of human eye were compared at different accommodation. The PV value of wavefront aberration from 0.718 waves increases gradually to 0.904 waves and RMS value from 0.21 waves to 0.26 waves when accommodative stimuli varies from 0 to - 5 diopters. The change of PV value is 0.186 waves which is less than the Rayleigh diffraction limit λ/4, and the change of RMS is 0.05 which under Marechal diffraction limit λ/14. Therefore, the change of the wavefront aberration caused accommodation can be ignored when wavefront aberrations in the human eye are corrected with surgery or wearing glasses.

  10. The Use of Computer Technology in Designing Appropriate Test Accommodations for English Language Learners

    ERIC Educational Resources Information Center

    Abedi, Jamal

    2014-01-01

    Among the several forms of accommodations used in the assessment of English language learners (ELLs), language-based accommodations are the most effective in making assessments linguistically accessible to these students. However, there are significant challenges associated with the implementation of many of these accommodations. This article…

  11. Effects of longitudinal chromatic aberration on accommodation and emmetropization.

    PubMed

    Seidemann, Anne; Schaeffel, Frank

    2002-09-01

    Less accommodation was found when human subjects read in blue (peak at about 440 nm) than when they read in red light (above 600 nm; [Kroger & Binder, British Journal of Ophthalmology 84 (2000) 890]). On the other hand, emmetropization in chickens did not appear to compensate for the chromatic defocus (385 nm versus 665 nm; [Rohrer, Schaeffel & Zrenner, Journal of Physiology 449 (1992) 363]). The apparently contradictory result was studied in more detail in humans and chickens. Accommodation was measured with an eccentric infrared photorefractor, the PowerRefractor, in human subjects reading under quasi-monochromatic illumination conditions. Chickens were refracted in quasi-monochromatic ambient illumination but with no particular fixation target. In a second experiment, they were also raised in monochromatic light for two days and subsequently refracted both in complete darkness, in monochromatic light, and in white light, both without and with cycloplegia. Consistent with the initial report by Kroger and Binder [British Journal of Ophthalmology 84 (2000) 890], accommodation in human subjects was found to shift in accordance with the chromatic aberration function. An immediate shift in accommodation tonus was also found in the chickens when they were refracted under red and in blue ambient illumination (average difference between refractions in both conditions: 1.26+/-0.54 D, p<0.001 paired t-test). This value is close to the chromatic focus difference between the two wavelengths (1.5 D [Mandelman & Sivak, Vision Research 23 (1983) 1555]). When chickens were raised in blue or red light for two days, and their refractions were subsequently measured in complete darkness, they showed also a difference in refractions (1.41+/-1.00 D; ANOVA: p<0.0012, post hoc t-test: at least p<0.05 among different groups). This difference was no longer significant when they were refracted in white light but became again significant when they were cyclopleged (0.57+/-0.58 D, p=0

  12. The Effect of Child Distress on Accommodation of Anxiety: Relations With Maternal Beliefs, Empathy, and Anxiety.

    PubMed

    Settipani, Cara A; Kendall, Philip C

    2017-01-01

    Little is known about the influence of child behaviors on accommodation of anxiety and how accommodation relates to other parent factors. The present study examined the comparative effect of high and low levels of child distress on mother-reported accommodation, mother factors in relation to accommodation, and moderators of the relation between accommodation and child distress. Maternal perceptions of accommodation were measured by vignettes depicting youth exhibiting high or low levels of distress in anxiety-provoking situations that elicited social anxiety, generalized anxiety, or separation anxiety in a sample of 7- to 17-year-old youth with anxiety disorders (N = 70, M = 11.66, 47.1% male). Findings indicated an effect of child distress on mother-reported accommodation of youth anxiety, such that mothers reported more overall accommodation under conditions of high child distress; situation-level analyses revealed this effect for social and generalized anxiety situations. Furthermore, an association was found between greater mother-reported accommodation and more negative beliefs about their child's experience of anxiety, which held across situations. Maternal empathy moderated the relation between overall accommodation and child distress. Maternal anxiety also moderated the relation between accommodation and child distress, with results varying based on situation type. Findings, consistent with theory, indicate a relation between child distress and mother-reported accommodation and suggest that maternal beliefs about anxiety are an important treatment target. High maternal empathy may be related to a greater degree of adaptability in response to child behaviors, whereas maternal anxiety may be linked with less adaptive responses to child behaviors.

  13. Accommodative intraocular lens versus standard monofocal intraocular lens implantation in cataract surgery.

    PubMed

    Ong, Hon Shing; Evans, Jennifer R; Allan, Bruce D S

    2014-05-01

    Following cataract surgery and intraocular lens (IOL) implantation, loss of accommodation or postoperative presbyopia occurs and remains a challenge. Standard monofocal IOLs correct only distance vision; patients require spectacles for near vision. Accommodative IOLs have been designed to overcome loss of accommodation after cataract surgery. To define (a) the extent to which accommodative IOLs improve unaided near visual function, in comparison with monofocal IOLs; (b) the extent of compromise to unaided distance visual acuity; c) whether a higher rate of additional complications is associated the use of accommodative IOLs. We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 9), Ovid MEDLINE, Ovid MEDLINE in-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily Update, Ovid OLDMEDLINE (January 1946 to October 2013), EMBASE (January 1980 to October 2013), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to October 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 10 October 2013. We include randomised controlled trials (RCTs) which compared implantation of accommodative IOLs to implantation of monofocal IOLs in cataract surgery. Two authors independently screened search results, assessed risk of bias and extracted data. All included trials used the 1CU accommodative IOL (HumanOptics, Erlangen, Germany) for their intervention group. One trial had an additional arm with the AT-45 Crystalens accommodative IOL (Eyeonics Vision). We performed a separate analysis comparing 1CU and AT-45 IOL. We included four RCTs, including 229 participants (256 eyes

  14. The Influence of Testing Accommodations on Academic Performance and Disciplinary Rates

    ERIC Educational Resources Information Center

    Taylor, Elizabeth

    2017-01-01

    The purpose of this study was to look at two testing accommodations (e.g., read aloud and calculator use) within an "educational" setting. Previous research regarding testing accommodations has most often been conducted within an experimental setting, and the results are conflicting. Therefore, this study was conducted to look at whether…

  15. Computer-Based Signing Accommodations: Comparing a Recorded Human with an Avatar

    ERIC Educational Resources Information Center

    Russell, Michael; Kavanaugh, Maureen; Masters, Jessica; Higgins, Jennifer; Hoffmann, Thomas

    2009-01-01

    Many students who are deaf or hard-of-hearing are eligible for a signing accommodation for state and other standardized tests. The signing accommodation, however, presents several challenges for testing programs that attempt to administer tests under standardized conditions. One potential solution for many of these challenges is the use of…

  16. Decoding depositional sequences in carbonate systems: Concepts vs experience

    NASA Astrophysics Data System (ADS)

    Pomar, Luis; Haq, Bilal U.

    2016-11-01

    Efficacy of sequence stratigraphic concepts in siliciclastic systems has been proven by successful applications in both academia and the industry over the past four decades. However, experience has demonstrated repeatedly that the relatively simple advective transportational approach of these models is less than successful when applied to the more complex carbonate systems and can lead to erroneous interpretations. Instead, an approach that includes the use of the changes in the biotic components of carbonate deposits to infer the sea-level trajectory and thereby placing it in the proper sequence framework is deemed to be more meaningful. This is exemplified with several well-studied examples that illustrate the variety of ways in which the biotic components can build carbonate platforms, and how these have changed through the ages prompted by biological evolution. This extended review discusses carbonate production, source to sink transportation influenced by sea-level changes, surface waves, as well as the less understood and under-appreciated internal waves, and the resulting variety of platforms that can be built by the interaction of these factors, as well as the changing patterns of biotic components with time. Their effect on the carbonate reservoir is considerable, understanding of which is the ultimate objective of carbonate research for applications in the industry. Key elements in the carbonate environments that differ from the siliciclastic systems are: 1) intrabasinal conditions (nutrients, salinity, temperature, water energy, transparency) are important controls on carbonate production and therefore also control in-situ accommodation and how it may be filled; 2) depositional accommodation can be both physical (controlled by hydrodynamics) and ecological (in the building-up above the base level mode); 3) because carbonates are products of biological activity, their production modes have been changing with time as their biotic components have evolved; 4

  17. 46 CFR 116.810 - Overnight accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... THAN 150 PASSENGERS OR WITH OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS CONSTRUCTION AND... space above. (b) Berths must not be located more than three high and must be constructed of wood, fiber... fitted with a suitable aid for access. (c) The construction and arrangement of berths and other furniture...

  18. Scheimpflug image-based changes in anterior segment parameters during accommodation induced by short-term reading.

    PubMed

    Lipecz, Agnes; Tsorbatzoglou, Alexis; Hassan, Ziad; Berta, Andras; Modis, Laszlo; Nemeth, Gabor

    2017-05-11

    To analyze the effect of the accommodation on the anterior segment data (corneal and anterior chamber parameters) induced by short-time reading in a healthy, nonpresbyopic adult patient group. Images of both eyes of nonpresbyopic volunteers were captured with a Scheimpflug device (Pentacam HR) in a nonaccommodative state. Fifteen minutes of reading followed and through fixation of the built-in target of Pentacam HR further accommodation was achieved and new images were captured by the device. Anterior segment parameters were observed and the differences were analyzed. Fifty-two healthy eyes of 26 subjects (range 20.04-28.58 years) were analyzed. No significant differences were observed in the keratometric values before and after the accommodative task (p = 0.35). A statistically significant difference was measured in the 5.0-mm-diameter and the 7.0-mm-diameter corneal volume (p = 0.01 and p = 0.03) between accommodation states. Corneal aberrometric data did not change significantly during short-term accommodation. Significant differences were observed between nonaccommodative and accommodative states of the eyes for all measured anterior chamber parameters. Among the parameters of the cornea, only corneal volume changed during the short-term accommodation process, showing some fine changes with accommodation of the cornea in young, emmetropic patients. The position of the pupil and the anterior chamber parameters were observed to change with accommodation as captured by a Scheimpflug device.

  19. Potential role for microfluctuations as a temporal directional cue to accommodation

    PubMed Central

    Metlapally, Sangeetha; Tong, Jianliang L.; Tahir, Humza J.; Schor, Clifton M.

    2016-01-01

    The goal was to revisit an important, yet unproven notion that accommodative microfluctuations facilitate the determination of direction (sign) of abrupt focus changes in the stimulus to accommodation. We contaminated the potential temporal cues from natural accommodative microfluctuations by presenting uncorrelated external (screen) temporal defocus noise that combined with the retinal image effects of natural microfluctuations. A polychromatic Maltese spoke pattern thus either modulated defocus at a combination of two temporal frequencies (on-screen noise condition) or was static (control condition). The on-screen conditions were combined with step changes in optical vergence that were randomized in direction and magnitude. Five subjects monocularly viewed stimuli through a Badal optical system in a Maxwellian view. An artificial 4-mm aperture was imaged at the entrance pupil of the eye. Wavefront aberrations were measured dynamically at 50 Hz using a custom Shack–Hartmann aberrometer. Dynamic changes in the Zernike defocus term with step changes in optical vergence were analyzed. We calculated the percentage of correct directional responses for 1, 2, and 3 D accommodative and disaccommodative step stimuli using preset criteria for latency, velocity, and persistence of the response. The on-screen noise condition reduced the percent-correct responses compared to the static stimulus, suggesting that this manipulation affected the detectability of the sign of the accommodative stimulus. Several possible reasons and implications of this result are discussed. PMID:27120075

  20. Morphology and accommodative function of the vitreous zonule in human and monkey eyes.

    PubMed

    Lütjen-Drecoll, Elke; Kaufman, Paul L; Wasielewski, Rainer; Ting-Li, Lin; Croft, Mary Ann

    2010-03-01

    To explore the attachments of the posterior zonule and vitreous in relation to accommodation and presbyopia in monkeys and humans. Novel scanning electron microscopy (SEM) and ultrasound biomicroscopy (UBM) techniques were used to visualize the anterior, intermediate, and posterior vitreous zonule and their connections to the ciliary body, vitreous membrane, lens capsule, and ora serrata, and to characterize their age-related changes and correlate them with loss of accommodative forward movement of the ciliary body. alpha-Chymotrypsin was used focally to lyse the vitreous zonule and determine the effect on movement of the accommodative apparatus in monkeys. The vitreous attached to the peripheral lens capsule and the ora serrata directly. The pars plana zonule and the posterior tines of the anterior zonule were separated from the vitreous membrane except for strategically placed attachments, collectively termed the vitreous zonule, that may modulate and smooth the forward and backward movements of the entire system. Age-dependent changes in these relationships correlated significantly with loss of accommodative amplitude. Lysis of the intermediate vitreous zonule partially restored accommodative movement. The vitreous zonule system may help to smoothly translate to the lens the driving forces of accommodation and disaccommodation generated by the ciliary muscle, while maintaining visual focus and protecting the lens capsule and ora serrata from acute tractional forces. Stiffening of the vitreous zonular system may contribute to age-related loss of accommodation and offer a therapeutic target for presbyopia.

  1. [The relationship between accommodative accuracy at different near-work distances and early-onset myopia].

    PubMed

    Yu, Q W; Zhang, P; Zhou, S B; Hu, Y; Ji, M X; Luo, Y C; You, H L; Yao, Z X

    2016-07-01

    To observe the accommodative accuracy of children with early-onset myopia at different near-work distances, and discuss the relationship between accommodative accuracy and early-onset myopia. This was a case-control study. Thirty-seven emmetropic children, 41 early-onset myopic children without correction, and 39 early-onset myopic children with spectacles, aged 7 to 13 years, were included. Measures of refractive errors and accommodative accuracy at four near-work distances, including 50 cm, 40 cm, 30 cm, and 20 cm, were made using the binocular fusion cross cylinder (FCC) of an automatic phoropter. Most candidates showed accommodative lags, including the children with emmetropia. The ratio of lags in all candidates at different near-work distances was 75.21% (50 cm), 87.18% (40 cm), 92.31% (30 cm), and 98.29% (20 cm), respectively. All accommodative accuracies became worse, and the accommodative lag ratio and values of FCC increased, along with the shortening of the distance. The difference in accommodative accuracy among groups was statistically significant at 30 cm (χ(2)=7.852, P= 0.020) and 20 cm (χ(2)=6.480, P=0.039). The values of FCC among groups were significantly different at 30 cm (F=3.626, P=0.030) and 20 cm (F=3.703, P=0.028), but not at 50 cm and 40 cm (P>0.05). In addition, the FCC values of 30 cm and 20 cm had a statistically significant difference between myopic children without correction [(1.25±0.44) D and (1.76±0.43) D] and emmetropic children [(0.95±0.52) D and (1.41±0.58) D] (P=0.012, 0.008). The correlation between diopters of myopia and accommodative accuracy at different nearwork distances was not statistically significant (P>0.05). However, the correlation between diopters of myopia and the accommodative lag value (FCC) at 20 cm was statistically significant (r=0.246, P=0.028). The closer the near-work distance is, the worse the accommodative accuracy is. This is more significant in early-onset myopia, especially myopia without

  2. Accommodation Decision Making for Postsecondary Students With Learning Disabilities: Individually Tailored or One Size Fits All?

    PubMed

    Weis, Robert; Dean, Emily L; Osborne, Karen J

    2016-09-01

    Clinicians uniformly recommend accommodations for college students with learning disabilities; however, we know very little about which accommodations they select and the validity of their recommendations. We examined the assessment documentation of a large sample of community college students receiving academic accommodations for learning disabilities to determine (a) which accommodations their clinicians recommended and (b) whether clinicians' recommendations were supported by objective data gathered during the assessment process. In addition to test and instructional accommodations, many clinicians recommended that students with learning disabilities should have different educational expectations, standards, and methods of evaluation (i.e., grading) than their nondisabled classmates. Many of their recommendations for accommodations were not supported by objective evidence from students' history, diagnosis, test data, and current functioning. Furthermore, clinicians often recommended accommodations that were not specific to the student's diagnosis or area of disability. Our findings highlight the need for individually selected accommodations matched to students' needs and academic contexts. © Hammill Institute on Disabilities 2014.

  3. Adaptations for English Language Learners: Differentiating between Linguistic and Instructional Accommodations

    ERIC Educational Resources Information Center

    Pappamihiel, N. Eleni; Lynn, C. Allen

    2016-01-01

    While many teachers and teacher educators in the United States K-12 system acknowledge that the English language learners (ELLs) in our schools need modifications and accommodations to help them succeed in school, few attempt to parse out how different types of accommodations may affect learning in the mainstream classroom, specifically linguistic…

  4. Computer Testing as a Form of Accommodation for English Language Learners

    ERIC Educational Resources Information Center

    Abedi, Jamal

    2009-01-01

    This study compared performance of both English language learners (ELLs) and non-ELL students in Grades 4 and 8 under accommodated and nonaccommodated testing conditions. The accommodations used in this study included a computerized administration of a math test with a pop-up glossary, a customized English dictionary, extra testing time, and…

  5. [Miyake-Apple video analysis of movement patterns of an accommodative intraocular lens implant].

    PubMed

    Auffarth, G U; Schmidbauer, J; Becker, K A; Rabsilber, T M; Apple, D J

    2002-11-01

    The potentially accommodative intraocular lens (IOL) is a new development in IOL design We evaluated the new Humanoptics 1CU accommodative IOL in a laboratory study with human post mortem autopsy eyes. Using the Miyake-Apple posterior view video technique, the movement pattern of the IOL was tested and observed from the posterior perspective. RESULTS. A circular bend at the level of the ciliary body applied slight circular force onto the sclera allowing the relaxation of the zonules. The shift of focus was demonstrated by using a reading target. In addition, viscoelastic was injected into the vitreous resulting in the same anterior movement of the IOL optic. The 1CU Humanoptics accommodative IOL showed potential accommodative behaviour in the laboratory. The accommodative (respectively pseudoaccommodative) effect was based on the anterior shift principle with anterior movement of the IOL-optic in the state of relaxing zonules. Whether this reflects the clinical situation, especially to this extent, must be further evaluated.

  6. Carbon nanotubes as nanotexturing agents for high power supercapacitors based on seaweed carbons.

    PubMed

    Raymundo-Piñero, Encarnación; Cadek, Martin; Wachtler, Mario; Béguin, François

    2011-07-18

    The advantages provided by multiwalled carbon nanotubes (CNTs) as backbones for composite supercapacitor electrodes are discussed. This paper particularly highlights the electrochemical properties of carbon composites obtained by pyrolysis of seaweed/CNTs blends. Due to the nanotexturing effect of CNTs, supercapacitors fabricated with electrodes from these composites exhibit enhanced electrochemical performances compared with CNT-free carbons. The cell resistance is dramatically reduced by the excellent conductivity of CNTs and by the good propagation of ions favored by the presence of opened mesopores. As a consequence, the specific power of supercapacitors based on these nanocomposites is very high. Another advantage related to the presence of CNTs is a better life cycle of the systems. The composite electrodes are resilient during the charge/discharge of capacitors; these are able to perfectly accommodate the dimensional changes appearing in the active material without mechanical damages. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. WORK CONTINUATION WHILE TREATED FOR BREAST CANCER: THE ROLE OF WORKPLACE ACCOMMODATIONS

    PubMed Central

    Neumark, David; Bradley, Cathy J.; Henry, Miguel

    2015-01-01

    Given the short- and long-term disabilities associated with breast cancer and its treatment, the authors investigate the influence of workplace accommodations on the employment and hours worked of women newly diagnosed with breast cancer. Accommodations that allow women to work fewer hours or that ease the burden of work could also generate health benefits by reducing workplace demands and allowing women more time to tend to treatment needs and recovery. In prior research, the authors found modest labor supply impacts on employment for this group of women. Evidence from this study suggests that some accommodations are associated with fewer hours worked, while some are associated with higher employment or hours. In addition, some of the accommodations that may affect hours of work—sometimes positively and sometimes negatively—are associated with positive health benefits. PMID:26778848

  8. Accommodations quality for students who are d/Deaf or hard of hearing.

    PubMed

    Cawthon, Stephanie W; Leppo, Rachel

    2013-01-01

    Students who are d/Deaf or hard of hearing often receive accommodations that are intended to increase access to the educational environment. The authors provide the results of a large national study of accommodations use in secondary and postsecondary settings. The article focuses on three aspects of accommodations use: access, quality, and consistency. The participants were 1,350 professionals working with a diverse group of students who were d/Deaf or hard of hearing in a variety of roles, including educators, administrators, interpreters, vocational rehabilitation agency staff, and allied service providers. Data were collected from both a national survey and a series of focus groups conducted over a 1-year period. The authors discuss the results in light of the crucial nature of accommodations during the transition into a variety of educational, training, and employment options.

  9. [Accommodation to monochromatic targets in people with different color vision statuses].

    PubMed

    Qian, Yishan; Huang, Jia; Chu, Renyuan

    2015-01-01

    To compare the accommodation response (AR) to monochromatic targets in subjects with different color vision statuses, and to investigate the role of color vision in the control of accommodation and emmetropization. It was a case-control study. Accommodation was measured with a dynamic infrared optometer while subjects [17 protans, 47 deutans, and 23 normals; mean age: (20.0 ± 4.4) years] viewed a (1) red on black or (2) green on black vertical square-wave gratings of iso-luminance (3 cycles/deg; 0.9 contrast) in a Badal optic system. The grating stepped 1.00 D towards the eye from an initial position of 0 D until 5.00 D. With red-black targets, the AR in the protans (AR = 1.98 D) was worse than that in the normals (AR = 2.55 D) when the accommodation stimulus (AS) was 4.00 D (LSD, P = 0.031). The AR in the deutans were worse than that in the normals when the AS was 3.00, 4.00, and 5.00 D (3.00 D: 1.23 D vs. 1.69 D, P = 0.002; 4.00 D: 1.89 D vs. 2.55 D, P = 0.002; 5.00 D: 2.40 D vs. 3.17 D, P = 0.003). With green-black targets, the AR in the protans were worse than that in the normals when the AS was 3.00 and 4.00 D (3.00 D: 1.13 D vs. 1.61 D, P = 0.004; 4.00 D: 1.80 D vs. 2.34 D, P = 0.021). In the deutans, the AR was worse with stimuli of 3.00, 4.00, and 5.00 D (3.00 D: 1.21 D vs. 1.61 D, P = 0.003; 4.00 D: 1.65 D vs. 2.34 D, P < 0.001; 5.00 D: 2.36 D vs. 2.93 D, P = 0.007). No significant differences between the protans and deutans were found for all the stimulus conditions. In the protans, accommodation to red-black targets was better than that to green-black targets when the stimulus was 2.00, 3.00, and 5.00 D (2.00 D: t = -2.81, P = 0.013; 3.00 D: t = -4.55, P < 0.001; 5.00 D: t = -3.15, P = 0.006). In the deutans, accommodation to red-black targets was better than that to green-black targets when the stimulus was 4.00 D (t = -2.19, P = 0.034). In the normals, accommodation to red-black targets were better than that to green-black targets when the stimulus

  10. Accommodation and age-dependent eye model based on in vivo measurements.

    PubMed

    Zapata-Díaz, Juan F; Radhakrishnan, Hema; Charman, W Neil; López-Gil, Norberto

    2018-03-21

    To develop a flexible model of the average eye that incorporates changes with age and accommodation in all optical parameters, including entrance pupil diameter, under photopic, natural, environmental conditions. We collated retrospective in vivo measurements of all optical parameters, including entrance pupil diameter. Ray-tracing was used to calculate the wavefront aberrations of the eye model as a function of age, stimulus vergence and pupil diameter. These aberrations were used to calculate objective refraction using paraxial curvature matching. This was also done for several stimulus positions to calculate the accommodation response/stimulus curve. The model predicts a hyperopic change in distance refraction as the eye ages (+0.22D every 10 years) between 20 and 65 years. The slope of the accommodation response/stimulus curve was 0.72 for a 25 years-old subject, with little change between 20 and 45 years. A trend to a more negative value of primary spherical aberration as the eye accommodates is predicted for all ages (20-50 years). When accommodation is relaxed, a slight increase in primary spherical aberration (0.008μm every 10 years) between 20 and 65 years is predicted, for an age-dependent entrance pupil diameter ranging between 3.58mm (20 years) and 3.05mm (65 years). Results match reasonably well with studies performed in real eyes, except that spherical aberration is systematically slightly negative as compared with the practical data. The proposed eye model is able to predict changes in objective refraction and accommodation response. It has the potential to be a useful design and testing tool for devices (e.g. intraocular lenses or contact lenses) designed to correct the eye's optical errors. Copyright © 2018 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

  11. Subcortical neural circuits for ocular accommodation and vergence in primates.

    PubMed

    Gamlin, P D

    1999-03-01

    Our current knowledge of the neural bases of vergence and accommodation has increased significantly over the past few years. The behavior of medial rectus motoneurons during vergence, which has been reported by a number of investigators, is described. The behavior of Edinger-Westphal neurons during accommodation is also described, as are the characteristics of midbrain near-response neurons in the supraoculomotor area. Evidence that some of these near-response neurons provide the vergence input to medial rectus motoneurons and possibly the accommodation input to Edinger-Westphal neurons is reviewed. Anatomical studies have shown that the midbrain near-response region receives input from two deep cerebellar nuclei, the posterior interposed and the fastigial nucleus. Single-unit recording in the posterior interposed nucleus has revealed cells that increase their activity during the far-response, and the behavior of these neurons is reviewed. In addition, studies of a precerebellar nucleus, the nucleus reticularis tegmenti pontis, have revealed some cells that increase their activity during the near-response and others that do so during the far-response. The behavior of these neurons is reviewed. This review documents the great strides that are occurring in our understanding of the anatomy and physiology of the neural pathways controlling vergence and accommodation in the primate.

  12. The accommodative ciliary muscle function is preserved in older humans

    NASA Astrophysics Data System (ADS)

    Tabernero, Juan; Chirre, Emmanuel; Hervella, Lucia; Prieto, Pedro; Artal, Pablo

    2016-05-01

    Presbyopia, the loss of the eye’s accommodation capability, affects all humans aged above 45-50 years old. The two main reasons for this to happen are a hardening of the crystalline lens and a reduction of the ciliary muscle functionality with age. While there seems to be at least some partial accommodating functionality of the ciliary muscle at early presbyopic ages, it is not yet clear whether the muscle is still active at more advanced ages. Previous techniques used to visualize the accommodation mechanism of the ciliary muscle are complicated to apply in the older subjects, as they typically require fixation stability during long measurement times and/or to have an ultrasound probe directly in contact with the eye. Instead, we used our own developed method based on high-speed recording of lens wobbling to study the ciliary muscle activity in a small group of pseudophakic subjects (around 80 years old). There was a significant activity of the muscle, clearly able to contract under binocular stimulation of accommodation. This supports a purely lenticular-based theory of presbyopia and it might stimulate the search for new solutions to presbyopia by making use of the remaining contraction force still presented in the aging eye.

  13. Persistent accommodative spasm nine years after head trauma.

    PubMed

    Bohlmann, B J; France, T D

    1987-09-01

    Spasm of the near reflex is most often seen on a functional basis in young adults with underlying emotional problems. In particular, when convergence spasm is associated with miosis on attempted lateral gaze, a functional basis for the disorder should be suspected. Patients who experience spasm of the near reflex following trauma commonly follow a benign course with spontaneous resolution of their ocular complaints within 1-2 years. Accommodative spasm, manifested by pseudomyopia, or spasm of convergence, alone, or in combination with miosis, may be found as isolated signs of spasm of the near reflex. We report a patient who continues to demonstrate accommodative spasm 9 years after a motor vehicle accident.

  14. Effect of temporal location of correction of monochromatic aberrations on the dynamic accommodation response

    PubMed Central

    Hampson, Karen M.; Chin, Sem Sem; Mallen, Edward A. H.

    2010-01-01

    Dynamic correction of monochromatic aberrations of the eye is known to affect the accommodation response to a step change in stimulus vergence. We used an adaptive optics system to determine how the temporal location of the correction affects the response. The system consists of a Shack-Hartmann sensor sampling at 20 Hz and a 37-actuator piezoelectric deformable mirror. An extra sensing channel allows for an independent measure of the accommodation level of the eye. The accommodation response of four subjects was measured during a +/− 0.5 D step change in stimulus vergence whilst aberrations were corrected at various time locations. We found that continued correction of aberrations after the step change decreased the gain for disaccommodation, but increased the gain for accommodation. These results could be explained based on the initial lag of accommodation to the stimulus and changes in the level of aberrations before and after the stimulus step change. Future considerations for investigations of the effect of monochromatic aberrations on the dynamic accommodation response are discussed. PMID:21258515

  15. Music Accommodation in Secondary Schools. A Design Guide. Building Bulletin 86.

    ERIC Educational Resources Information Center

    Watson, Lucy; Wadsworth, Alison; Nichols, Helen; Daniels, Richard; Marshall, Christopher; Orlowski, Rafal

    This document provides guidance on accommodations in secondary schools, concentrating on the needs of 11- to 16-year-old pupils. The guidance is intended to assist all those who may be involved in the briefing and design process. It discusses the issues that arise when considering both new and existing accommodations. The document covers the range…

  16. 78 FR 10263 - Proposed Collection; Comment Request for ADA Accommodations Request Packet

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-13

    ... DEPARTMENT OF THE TREASURY Internal Revenue Service Proposed Collection; Comment Request for ADA... the ADA Accommodations Packet. DATES: Written comments should be received on or before April 15, 2013...: ADA Accommodations Request Packet. OMB Number: 1545-2027. Abstract: Information is collected so that...

  17. First-principles study of uranium carbide: Accommodation of point defects and of helium, xenon, and oxygen impurities

    NASA Astrophysics Data System (ADS)

    Freyss, Michel

    2010-01-01

    Point defects and volatile impurities (helium, xenon, oxygen) in uranium monocarbide UC are studied by first-principles calculations. Preliminarily, bulk properties of UC and of two other uranium carbide phases, UC2 and U2C3 , are calculated in order to compare them to experimental data and to get confidence in the use of the generalized gradient approximation for this class of compounds. The subsequent study of different types of point defects shows that the carbon sublattice best accommodates the defects. The perturbation of the crystal structure induced by the defects is weak and the interaction between defects is found short range. Interstitial carbon dumbbells possibly play an important role in the diffusion of carbon atoms. The most favorable location of diluted helium, xenon, and oxygen impurities in the UC crystal lattice is then determined. The rare-gas atoms occupy preferably a uranium substitution site or a uranium site in a U-C bivacancy. But their incorporation in UC is, however, not energetically favorable, especially for xenon, suggesting their propensity to diffuse in the material and/or form bubbles. On the other hand, oxygen atoms are very favorably incorporated as diluted atoms in the UC lattice, confirming the easy oxidation of UC. The oxygen atoms preferably occupy a carbon substitution site or the carbon site of a U-C bivacancy. Our results are compared to available experimental data on UC and to similar studies by first-principles calculations for other carbides and nitrides with the rock-salt structure.

  18. Whole eye axial biometry during accommodation using ultra-long scan depth optical coherence tomography

    PubMed Central

    Zhong, Jianguang; Tao, Aizhu; Xu, Zhe; Jiang, Hong; Shao, Yilei; Zhang, Huicheng; Liu, Che; Wang, Jianhua

    2014-01-01

    PURPOSE To investigate changes of whole eye axial biometry during accommodation using ultra-long scan depth optical coherence tomography (UL-OCT). DESIGN Prospective, observational case series. METHODS Twenty-one adult subjects were enrolled. Using UL-OCT, the left eye of each subject was imaged with relaxed (0 D) and accommodative stimuli (+6 D). Full eye biometry included central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness, vitreous length and axial length (AL). RESULTS During accommodation (+6 D), the axial biometry of the whole eye changed significantly. Compared to the rest state, ACD at the accommodative state decreased significantly from 3.128 ± 0.305 mm to 2.961 ± 0.298 mm (paired t-test, P < 0.001). The lens thickness increased significantly from 3.723 ± 0.237 mm to 3.963 ± 0.234 mm (P < 0.001). The vitreous length decreased significantly from 17.129 ± 0.864 mm to 17.057± 0.848 mm (P < 0.001). AL was 24.519 ± 0.917 mm at the rest state and increased to 24.545±0.915 mm with +6 D accommodation stimulus. The elongated AL of 26.1 ± 13.4 μm between the rest and accommodative states was significant (P < 0.001). CONCLUSIONS During accommodation, whole eye axial biometry changed, including a decrease in ACD and vitreous length, and an increase in lens thickness and AL. UL-OCT provides an alternative method that is suitable for full eye biometry during accommodation. PMID:24487051

  19. Documenting a modern day transgressive surface in a carbonate ramp setting

    NASA Astrophysics Data System (ADS)

    Lokier, Stephen; Paul, Andreas

    2017-04-01

    The low-angle carbonate ramp geometry of the Abu Dhabi coastline provides an ideal site for studying the effects of marine transgression in a setting analogous to Mesozoic epeiric seas. Supratidal sabkha evaporite precipitation passes offshore, through a broad and complex carbonate-evaporite intertidal environment, into a subtidal carbonate depositional setting. The coast of the mainland is locally isolated from open-marine conditions by a number of peninsulas and islands associated with the east-west trending Great Pearl Bank. This study combined 12 years of fieldwork observations with historical satellite imagery in order to establish multiple lines of evidence for active retrogradation over a 15 km length of coastline in the Abu Dhabi sabkha. Surveyed transects of the sabkha yield an average slope angle of 0.02°. Employing a current estimate of global sea level rise of 3.3 mm/yr, we calculate an expected present-day marine transgression of 7.9 m/yr. The landward and seaward boundaries of the microbial mat facies belt are strongly controlled by the location of the intertidal zone. The seaward limit of the Recent microbial mat belt in the Abu Dhabi Sabkha is currently being buried beneath retrograding lower-intertidal sediments whilst the landward side is simultaneously backstepping over previously-supratidal gypsum-dominated facies. The landward migration of spits and beach ridges was monitored at several locations with rates of retrogradation of up to 28 m per year being recorded locally. The study also identified numerous erosive features that are consistent with an increase in energy regimes. There has been a significant increase in denudation of the microbial mat, causing underlying sediment to be increasingly susceptible to erosion. In the lowermost intertidal zone, erosion of the hardground and other facies is observed. Clasts from the hardground are transported landward onto the surface of the sabkha where they are incorporated within other facies. This

  20. An evaluation of the lag of accommodation using photorefraction.

    PubMed

    Seidemann, Anne; Schaeffel, Frank

    2003-02-01

    The lag of accommodation which occurs in most human subjects during reading has been proposed to explain the association between reading and myopia. However, the measured lags are variable among different published studies and current knowledge on its magnitude rests largely on measurements with the Canon R-1 autorefractor. Therefore, we have measured it with another technique, eccentric infrared photorefraction (the PowerRefractor), and studied how it can be modified. Particular care was taken to ensure correct calibration of the instrument. Ten young adult subjects were refracted both in the fixation axis of the right eye and from the midline between both eyes, while they read text both monocularly and binocularly at 1.5, 2, 3, 4 and 5 D distance ("group 1"). A second group of 10 subjects ("group 2"), measured from the midline between both eyes, was studied to analyze the effects of binocular vs monocular vision, addition of +1 or +2 D lenses, and of letter size. Spherical equivalents (SE) were analyzed in all cases. The lag of accommodation was variable among subjects (standard deviations among groups and viewing distances ranging from 0.18 to 1.07 D) but was significant when the measurements were done in the fixation axis (0.35 D at 3 D target distance to 0.60 D at 5 D with binocular vision; p<0.01 or better all cases). Refracting from the midline between both eyes tended to underestimate the lag of accommodation although this was significant only at 5 D (ANOVA: p<0.0001, post hoc t-test: p<0.05). There was a small improvement in accommodation precision with binocular compared to monocular viewing but significance was reached only for the 5 D reading target (group 1--lags for a 3/4/5 D target: 0.35 vs 0.41 D/0.48 vs 0.47 D/0.60 vs 0.66 D, ANOVA: p<0.0001, post hoc t-test: p<0.05; group 2--0.29 vs 0.12 D, 0.33 vs 0.16 D, 0.23 vs -0.31 D, ANOVA: p<0.0001, post hoc t-test: p<0.05). Adjusting the letter height for constant angular subtense (0.2 deg) induced

  1. Cultural Accommodation as Method and Metaphor

    ERIC Educational Resources Information Center

    Leong, Frederick T. L.

    2007-01-01

    The author summarizes the cultural accommodation model (CAM) of cross-cultural psychotherapy (F. T. L. Leong & S. H. Lee, 2006). This summary is divided into 2 parts, with the 1st part describing the theoretical development of the CAM as a method of psychotherapy and the research approach underlying it. This section includes a description of the…

  2. Accommodation and convergence palsy caused by lesions in the bilateral rostral superior colliculus.

    PubMed

    Ohtsuka, Kenji; Maeda, Sachie; Oguri, Naomi

    2002-03-01

    To report a patient who developed accommodation and convergence palsy caused by lesions in the bilateral rostral superior colliculus. Observational case report. A 30-year-old right-handed man experienced sudden onset of diplopia and blurred vision at near vision. The patient showed accommodation and convergence palsy. Magnetic resonance imaging revealed lesions located in the bilateral rostral superior colliculus. These findings suggest that the rostral superior colliculus is involved in the control of accommodation and vergence eye movements.

  3. Fast scanning photoretinoscope for measuring peripheral refraction as a function of accommodation.

    PubMed

    Tabernero, Juan; Schaeffel, Frank

    2009-10-01

    A new device was designed to provide fast measurements (4 s) of the peripheral refraction (90 degrees central horizontal field). Almost-continuous traces are obtained with high angular resolution (0.4 degrees) while the subject is fixating a central stimulus. Three-dimensional profiles can also be measured. The peripheral refractions in 10 emmetropic subjects were studied as a function of accommodation (200 cm, 50 cm, and 25 cm viewing distances). Peripheral refraction profiles were largely preserved during accommodation but were different in each individual. Apparently, the accommodating lens changes its focal length evenly over the central 90 degrees of the visual field.

  4. Change in convergence and accommodation after two weeks of eye exercises in typical young adults

    PubMed Central

    Horwood, Anna M.; Toor, Sonia S.; Riddell, Patricia M.

    2014-01-01

    Background Although eye exercises appear to help heterophoria, convergence insufficiency, and intermittent strabismus, results can be confounded by placebo, practice, and encouragement effects. This study assessed objective changes in vergence and accommodation responses in naive young adults after a 2-week period of eye exercises under controlled conditions to determine the extent to which treatment effects occur over other factors. Methods Asymptomatic young adults were randomly assigned to one of two no-treatment (control) groups or to one of six eye exercise groups: accommodation, vergence, both, convergence in excess of accommodation, accommodation in excess of convergence, and placebo. Subjects were tested and retested under identical conditions, except for the second control group, who were additionally encouraged. Objective accommodation and vergence were assessed to a range of targets moving in depth containing combinations of blur, disparity, and proximity/looming cues. Results A total of 156 subjects were included. Response gain improved more for less naturalistic targets where more improvement was possible. Convergence exercises improved vergence for near across all targets (P = 0.035). Mean accommodation changed similarly but nonsignificantly. No other treatment group differed significantly from the nonencouraged control group, whereas encouraging effort produced significantly increased vergence (P = 0.004) and accommodation (P = 0.005) gains in the second control group. Conclusions True treatment effects were small, significantly better only after vergence exercises to a nonaccommodative target, and rarely related to the response they were designed to improve. Exercising accommodation without convergence made no difference to accommodation to cues containing detail. Additional effort improved objective responses the most. PMID:24582466

  5. Clinical evaluation of accommodation and ocular surface stability relavant to visual asthenopia with 3D displays

    PubMed Central

    2014-01-01

    Background To validate the association between accommodation and visual asthenopia by measuring objective accommodative amplitude with the Optical Quality Analysis System (OQAS®, Visiometrics, Terrassa, Spain), and to investigate associations among accommodation, ocular surface instability, and visual asthenopia while viewing 3D displays. Methods Fifteen normal adults without any ocular disease or surgical history watched the same 3D and 2D displays for 30 minutes. Accommodative ability, ocular protection index (OPI), and total ocular symptom scores were evaluated before and after viewing the 3D and 2D displays. Accommodative ability was evaluated by the near point of accommodation (NPA) and OQAS to ensure reliability. The OPI was calculated by dividing the tear breakup time (TBUT) by the interblink interval (IBI). The changes in accommodative ability, OPI, and total ocular symptom scores after viewing 3D and 2D displays were evaluated. Results Accommodative ability evaluated by NPA and OQAS, OPI, and total ocular symptom scores changed significantly after 3D viewing (p = 0.005, 0.003, 0.006, and 0.003, respectively), but yielded no difference after 2D viewing. The objective measurement by OQAS verified the decrease of accommodative ability while viewing 3D displays. The change of NPA, OPI, and total ocular symptom scores after 3D viewing had a significant correlation (p < 0.05), implying direct associations among these factors. Conclusions The decrease of accommodative ability after 3D viewing was validated by both subjective and objective methods in our study. Further, the deterioration of accommodative ability and ocular surface stability may be causative factors of visual asthenopia in individuals viewing 3D displays. PMID:24612686

  6. Image registration reveals central lens thickness minimally increases during accommodation

    PubMed Central

    Schachar, Ronald A; Mani, Majid; Schachar, Ira H

    2017-01-01

    Purpose To evaluate anterior chamber depth, central crystalline lens thickness and lens curvature during accommodation. Setting California Retina Associates, El Centro, CA, USA. Design Healthy volunteer, prospective, clinical research swept-source optical coherence biometric image registration study of accommodation. Methods Ten subjects (4 females and 6 males) with an average age of 22.5 years (range: 20–26 years) participated in the study. A 45° beam splitter attached to a Zeiss IOLMaster 700 (Carl Zeiss Meditec Inc., Jena, Germany) biometer enabled simultaneous imaging of the cornea, anterior chamber, entire central crystalline lens and fovea in the dilated right eyes of subjects before, and during focus on a target 11 cm from the cornea. Images with superimposable foveal images, obtained before and during accommodation, that met all of the predetermined alignment criteria were selected for comparison. This registration requirement assured that changes in anterior chamber depth and central lens thickness could be accurately and reliably measured. The lens radii of curvatures were measured with a pixel stick circle. Results Images from only 3 of 10 subjects met the predetermined criteria for registration. Mean anterior chamber depth decreased, −67 μm (range: −0.40 to −110 μm), and mean central lens thickness increased, 117 μm (range: 100–130 μm). The lens surfaces steepened, anterior greater than posterior, while the lens, itself, did not move or shift its position as appeared from the lack of movement of the lens nucleus, during 7.8 diopters of accommodation, (range: 6.6–9.7 diopters). Conclusion Image registration, with stable invariant references for image correspondence, reveals that during accommodation a large increase in lens surface curvatures is associated with only a small increase in central lens thickness and no change in lens position. PMID:28979092

  7. Mechanism for accommodation to cadmium exposure in Escherichia coli B

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kitchen, J.R. Jr.

    1989-01-01

    All organisms possess, to varying degrees, the ability to adapt to changes in their environment. The extent of this capability can be the determining factor in whether or not an organism survives. The adaptation of the enteric microorganism, Escherichia coli, to the heavy metal cadmium is not the result of a beneficial mutation, and has been termed accommodation. A protein was found that binds to, and appears to be induced by cadmium. The work presented in this thesis is directed at (1) determining the mechanism of accommodation of E.coli to cadmium, and (2) determining the potential role of a putativemore » cadmium binding-protein in accomplishing this accommodation. The presence of three chemically related cadmium-binding proteins, possessing molecular weights of 150,000, 67,000, and 38,000, respectively, was demonstrated. The cadmium-protein bond in the 150 and 67 kDa proteins was stable when boiled in sodium dodecyl sulfate, but was lost in the presence of reducing agents. Evidence was obtained which supported the assertion that the lower molecular weight cadmium-binding proteins were proteolytic or oxidative breakdown products of the larger cadmium-binding proteins. The loss of cadmium-binding activity was time dependent, and appeared to be accelerated by the presence of high salt. To determine if the process of accommodation involved the sequestration of cadmium in the outer cell surface, subcellular fractionation experiments were performed under a variety of post-exposure conditions. The possibility that the cell surface was rendered impermeable to cadmium ions during its recovery was also examined. Neither of these processes was found to be involved in the accommodative response. Indeed, the results of these studies support the concept that E.coli circumvents the presence of internal cadmium by converting it to a form that is no longer toxic to the cell.« less

  8. Academic Accommodations for Students with Psychiatric Disabilities.

    ERIC Educational Resources Information Center

    Souma, Alfred; Rickerson, Nancy; Burgstahler, Sheryl

    This brief paper summarizes the literature on academic accommodations for students with psychiatric disabilities. A definition of psychiatric disability precedes a brief summary of the following specific psychiatric diagnoses: depression, bipolar affective disorder; borderline personality disorder; schizophrenia; and anxiety disorders. Also noted…

  9. Convergence accommodation to convergence (CA/C) ratio in patients with intermittent exotropia and decompensated exophoria.

    PubMed

    Nonaka, Fumitaka; Hasebe, Satoshi; Ohtsuki, Hiroshi

    2004-01-01

    To evaluate the convergence accommodation to convergence (CA/C) ratio in strabismic patients and to clarify its clinical implications. Seventy-eight consecutive patients (mean age: 12.9 +/- 6.0 years) with intermittent exotropia and decompensated exophoria who showed binocular fusion at least at near viewing were recruited. The CA/C ratio was estimated by measuring accommodative responses induced by horizontal prisms with different magnitudes under accommodation feedback open-loop conditions. The CA/C ratios were compared with accommodative convergence to accommodation (AC/A) ratios and other clinical parameters. A linear regression analysis indicated that the mean (+/-SD) CA/C ratio was 0.080 +/- 0.043 D/prism diopter or 0.48 +/- 0.26 D/meter angle. There was no inverse or reciprocal relationship between CA/C and AC/A ratios. The patients with lower CA/C ratios tended to have smaller tonic accommodation under binocular viewing conditions and larger exodeviation at near viewing. The CA/C ratio, like the AC/A ratio, is an independent parameter that characterizes clinical features. A lower CA/C may be beneficial for the vergence control system to compensate for ocular misalignment with minimum degradation of accommodation accuracy.

  10. 36 CFR 5.9 - Discrimination in furnishing public accommodations and transportation services.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Discrimination in furnishing public accommodations and transportation services. 5.9 Section 5.9 Parks, Forests, and Public Property... furnishing public accommodations and transportation services. (a) The proprietor, owner or operator and the...

  11. Impact of Information Incongruity and Authors Group Membership on Assimilation and Accommodation

    ERIC Educational Resources Information Center

    Moskaliuk, J.; Matschke, C.

    2018-01-01

    Learning is a complex process that can be differentiated into assimilation and accommodation. The Internet enables both types of learning through collaboration. There is, however, little research investigating the specific impact of social and information incongruity on assimilation and accommodation. The current research investigates how the…

  12. 41 CFR 301-10.160 - What classes of train accommodations are available?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... business-class. (1) First-class—Includes bedrooms, roomettes, club service, parlor car accommodations or other premium accommodations. (2) Business-class—A class of extra fare train service that is offered... includes a level of service available to all passengers regardless of the fare paid. Coach-class includes...

  13. Family accommodation in obsessive-compulsive disorder: Relation to symptom dimensions, clinical and family characteristics.

    PubMed

    Albert, Umberto; Bogetto, Filippo; Maina, Giuseppe; Saracco, Paola; Brunatto, Cinthia; Mataix-Cols, David

    2010-09-30

    Family accommodation is the term used to indicate the process whereby family members of patients with obsessive-compulsive disorder (OCD) assist or participate in the patients' rituals. Family accommodation is a relatively under-researched phenomenon in OCD but an important one because it may be predictive of poor treatment outcome. This study systematically examined several socio-demographic and clinical variables that are associated with family accommodation in a well-characterized sample of adult patients and their healthy family members. Experienced clinicians administered the Family Accommodation Scale (FAS) to 141 psychopathology-free family members cohabiting with 97 patients with OCD. The items of the FAS were first subjected to principal component analysis (PCA) and the resulting domains of family accommodation (Participation, Modification, and Distress and Consequences) introduced as dependent variables in a series of multiple regression models assessing the relationship between family accommodation domains and a wide range of clinical variables, including Axis I and II psychopathology and symptom dimensions derived from the Yale-Brown Obsessive-Compulsive Scale (YBOCS) Symptom Checklist. The results showed that family accommodation was common, with the provision of reassurance, participation in rituals and assisting the patient in avoidance being the most frequent practices (occurring on a daily basis in 47%, 35%, and 43% of family members, respectively). The PCA of the YBOCS Symptom Checklist yielded four symptom dimensions, which were identical to those previously identified in the international literature. Multiple linear regression analyses showed that a higher score on the contamination/washing symptom dimension and a positive family history for an anxiety disorder other than OCD (referring to a family member other than the participant in this study) predicted greater scores on several domains of family accommodation. Our study confirms that family

  14. Quantification of the ciliary muscle and crystalline lens interaction during accommodation with synchronous OCT imaging

    PubMed Central

    Ruggeri, Marco; de Freitas, Carolina; Williams, Siobhan; Hernandez, Victor M.; Cabot, Florence; Yesilirmak, Nilufer; Alawa, Karam; Chang, Yu-Cherng; Yoo, Sonia H.; Gregori, Giovanni; Parel, Jean-Marie; Manns, Fabrice

    2016-01-01

    Abstract: Two SD-OCT systems and a dual channel accommodation target were combined and precisely synchronized to simultaneously image the anterior segment and the ciliary muscle during dynamic accommodation. The imaging system simultaneously generates two synchronized OCT image sequences of the anterior segment and ciliary muscle with an imaging speed of 13 frames per second. The system was used to acquire OCT image sequences of a non-presbyopic and a pre-presbyopic subject accommodating in response to step changes in vergence. The image sequences were processed to extract dynamic morphological data from the crystalline lens and the ciliary muscle. The synchronization between the OCT systems allowed the precise correlation of anatomical changes occurring in the crystalline lens and ciliary muscle at identical time points during accommodation. To describe the dynamic interaction between the crystalline lens and ciliary muscle, we introduce accommodation state diagrams that display the relation between anatomical changes occurring in the accommodating crystalline lens and ciliary muscle. PMID:27446660

  15. Quantification of the ciliary muscle and crystalline lens interaction during accommodation with synchronous OCT imaging.

    PubMed

    Ruggeri, Marco; de Freitas, Carolina; Williams, Siobhan; Hernandez, Victor M; Cabot, Florence; Yesilirmak, Nilufer; Alawa, Karam; Chang, Yu-Cherng; Yoo, Sonia H; Gregori, Giovanni; Parel, Jean-Marie; Manns, Fabrice

    2016-04-01

    Two SD-OCT systems and a dual channel accommodation target were combined and precisely synchronized to simultaneously image the anterior segment and the ciliary muscle during dynamic accommodation. The imaging system simultaneously generates two synchronized OCT image sequences of the anterior segment and ciliary muscle with an imaging speed of 13 frames per second. The system was used to acquire OCT image sequences of a non-presbyopic and a pre-presbyopic subject accommodating in response to step changes in vergence. The image sequences were processed to extract dynamic morphological data from the crystalline lens and the ciliary muscle. The synchronization between the OCT systems allowed the precise correlation of anatomical changes occurring in the crystalline lens and ciliary muscle at identical time points during accommodation. To describe the dynamic interaction between the crystalline lens and ciliary muscle, we introduce accommodation state diagrams that display the relation between anatomical changes occurring in the accommodating crystalline lens and ciliary muscle.

  16. The visual accommodation response during concurrent mental activity

    NASA Technical Reports Server (NTRS)

    Malmstrom, F. V.; Randle, R. J.; Bendix, J. S.; Weber, R. J.

    1980-01-01

    The direction and magnitude of the human visual accommodation response during concurrent mental activity are investigated. Subject focusing responses to targets at distances of 0.0 D, 3.0 D and an indeterminate distance were monitored by means of an optometer during the performance of a backwards counting task and a visual imagery task (thinking near and thinking far). In both experiments a shift in accommodation towards the visual far point is observed particularly for the near target, which increases with the duration of the task. The results can be interpreted in terms of both the capacity model of Kahneman (1973) and the autonomic arousal model of Hess and Polt (1964), and are not inconsistent with the possibility of an intermediate resting position.

  17. Carbon phenolic heat shields for Jupiter/Saturn/Uranus entry probes

    NASA Technical Reports Server (NTRS)

    Mezines, S.

    1974-01-01

    Carbon phenolic heat shield technology is reviewed. Heat shield results from the outer planetary probe mission studies are summarized along with results of plasma jet testing of carbon phenolic conducted in a ten megawatt facility. Missile flight data is applied to planetary entry conditions. A carbon phenolic heat shield material is utilized and tailored to accommodate each of the probe missions. An integral heat shield approach is selected over in order to eliminate a high temperature interface problem and permit direct bonding of the carbon phenolic to the structural honeycomb sandwich. The sandwich is filled with a very fine powder to minimize degradation of its insulation properties by the high conductive hydrogen/helium gases during the long atmospheric descent phase.

  18. Negotiating accommodations so that work-based education facilitates career development for youth with disabilities.

    PubMed

    Hutchinson, Nancy L; Versnel, Joan; Chin, Peter; Munby, Hugh

    2008-01-01

    Workers with disabilities are entitled to have their individual needs accommodated in a way that allows them to perform the essential duties of their job. However, adults with disabilities are often lacking in career development and are ill-prepared to negotiate workplace accommodations. This has led educators to seek workplaces that can accommodate the needs of adolescents with disabilities, so these adolescents can learn to negotiate accommodations and enhance their career development through work-based education. This paper reports on two case studies in which employers had agreed to accommodate the needs of adolescents with disabilities participating in work-based education. Social Cognitive Career Theory (SCCT) framed the analyses of these two cases - a case of a student with physical disabilities and a case of a student with developmental disabilities. SCCT proves valuable in understanding the role of work-based education in the career development of disabled youth.

  19. 46 CFR 190.20-20 - Sleeping accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Sleeping accommodations. 190.20-20 Section 190.20-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Accomodations for Officers, Crew, and Scientific Personnel § 190.20-20 Sleeping...

  20. Determining Appropriate Accommodations for Postsecondary Students with Reading and Written Expression Disorders

    ERIC Educational Resources Information Center

    Lindstrom, Jennifer H.

    2007-01-01

    One of the most significant barriers facing postsecondary students with reading and written expression disorders who are eligible to receive specific accommodations is the lack of professional knowledge pertaining to issues surrounding accommodations. Though guided by Section 504 of the Rehabilitation Act of 1973 and the Americans with…

  1. A Structural Equation Analysis of Family Accommodation in Pediatric Obsessive-Compulsive Disorder

    ERIC Educational Resources Information Center

    Caporino, Nicole E.; Morgan, Jessica; Beckstead, Jason; Phares, Vicky; Murphy, Tanya K.; Storch, Eric A.

    2012-01-01

    Family accommodation of symptoms is counter to the primary goals of cognitive-behavioral therapy for pediatric obsessive-compulsive disorder (OCD) and can pose an obstacle to positive treatment outcomes. Although increased attention has been given to family accommodation in pediatric OCD, relatively little is known about associated child and…

  2. Change in convergence and accommodation after two weeks of eye exercises in typical young adults.

    PubMed

    Horwood, Anna M; Toor, Sonia S; Riddell, Patricia M

    2014-04-01

    Although eye exercises appear to help heterophoria, convergence insufficiency, and intermittent strabismus, results can be confounded by placebo, practice, and encouragement effects. This study assessed objective changes in vergence and accommodation responses in naive young adults after a 2-week period of eye exercises under controlled conditions to determine the extent to which treatment effects occur over other factors. Asymptomatic young adults were randomly assigned to one of two no-treatment (control) groups or to one of six eye exercise groups: accommodation, vergence, both, convergence in excess of accommodation, accommodation in excess of convergence, and placebo. Subjects were tested and retested under identical conditions, except for the second control group, who were additionally encouraged. Objective accommodation and vergence were assessed to a range of targets moving in depth containing combinations of blur, disparity, and proximity/looming cues. A total of 156 subjects were included. Response gain improved more for less naturalistic targets where more improvement was possible. Convergence exercises improved vergence for near across all targets (P = 0.035). Mean accommodation changed similarly but nonsignificantly. No other treatment group differed significantly from the nonencouraged control group, whereas encouraging effort produced significantly increased vergence (P = 0.004) and accommodation (P = 0.005) gains in the second control group. True treatment effects were small, significantly better only after vergence exercises to a nonaccommodative target, and rarely related to the response they were designed to improve. Exercising accommodation without convergence made no difference to accommodation to cues containing detail. Additional effort improved objective responses the most. Copyright © 2014 American Association for Pediatric Ophthalmology and Strabismus. Published by Mosby, Inc. All rights reserved.

  3. The availability of smoking-permitted accommodations from Airbnb in 12 Canadian cities

    PubMed Central

    Kennedy, Ryan David; Douglas, Ornell; Stehouwer, Lindsay; Dawson, Jackie

    2018-01-01

    Purpose Airbnb is a web-based peer-to-peer (P2P) service that enables potential hosts and guests to broker accommodations in private homes as an alternative to traditional hotels. The hospitality sector has increasingly gone smoke-free over the last decade. This study identified the availability and cost of smoking-permitted accommodations identified on Airbnb. Methods The study team searched for Airbnb accommodations in 12 Canadian cities across each of Canada’s 10 provinces. Searches included availability for a single person for a private room, or double occupancy for an entire home/apartment; searches were for 1-night and 1-week stays. Results Cities across Canada, including Regina, Fredericton and Charlottetown, had no smoking-permitted accommodations available for the searches conducted. The proportion of private rooms available for one night that permitted smoking ranged from 2% in Calgary, 4% in Winnipeg and St. John’s, 10% in Halifax and Victoria, 18% in Toronto, 45% in Vancouver and 69% in Montréal. The average cost for a private room for one night in Vancouver was $128, while the cost for a private room that permits smoking was $62; however, in other markets prices were more similar. Discussion Across Canada, there is a wide range of smoking-permitted accommodations available through Airbnb. In some markets, smoking-permitted accommodation may be significantly less expensive than smoke-free options. As hotel chains increasingly go smoke-free, it is possible that the marketplace will respond with offerings to fulfil consumer demand. As policy makers consider how to regulate P2P services like Airbnb, public health considerations should be included. PMID:28219974

  4. Accommodative Esotropia Treatment Plan Utilizing Simultaneous Strabismus Surgery and Photorefractive Keratectomy.

    PubMed

    Eustis, H Sprague; Shah, Pulin

    2018-03-01

    Accommodative esotropia is a common cause of acquired esotropia. Pathogenesis varies among patients but usually includes excessive hyperopia and a high accommodative convergence/accommodation ratio or tight medial recti. The present study reviews an individualized treatment plan combining photorefractive keratectomy (PRK) and strabismus surgery to correct these problems. This study is a retrospective, interventional case series. Records for 15 patients who were treated for accommodative esotropia were reviewed. Patient ages ranged from 11 to 19 years. PRK and strabismus surgery were performed on 11 patients, and PRK only on 4 patients. The goal was to create a physiologic refractive error, good visual acuity (VA), and straight eyes without correction. All patients were spectacle free at 6-month follow-up. Twenty-four of 30 eyes had VA equal to preoperative VA without correction. Three eyes had a 1-line reduction and 2-line reduction in VA. The alignment results were ±10 prism diopters in 13 of 15 patients. Spherical refractive outcomes were 18 of 30 eyes within 1 diopter (D) of target and 12 of 30 eyes within 2 D of target. Astigmatism refractive outcomes were 21 of 30 eyes <1 D, 7 eyes 1-2 D, and 2 eyes >2 D. Two patients complained of halos at night, and 1 patient had peripheral corneal haze. Simultaneous PRK and strabismus surgery is safe and effective in treating accommodative esotropia. An individualized treatment plan can result in a physiologic refractive error, good VA, and a spectacle-free existence. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. TARDEC FIXED HEEL POINT (FHP): DRIVER CAD ACCOMMODATION MODEL VERIFICATION REPORT

    DTIC Science & Technology

    2017-11-09

    SUPPLEMENTARY NOTES N/A 14. ABSTRACT Easy-to-use Computer-Aided Design (CAD) tools, known as accommodation models, are needed by the ground vehicle... designers when developing the interior workspace for the occupant. The TARDEC Fixed Heel Point (FHP): Driver CAD Accommodation Model described in this...is intended to provide the composite boundaries representing the body of the defined target design population, including posture prediction

  6. [Mental Disorders and Reasonable Accommodation at Work: The Potential of Quebec Law].

    PubMed

    Laflamme, Anne-Marie

    Objectives Being able to work constitutes a powerful social integration vector for those suffering from mental health disorders, while also providing therapeutic benefits for them. Yet, despite some advances in this regard, such persons are still denied employment. The obstacles to their full workforce integration reside in the prejudices surrounding the disorders affecting them and the need to adapt tasks to their needs and abilities. The International Convention on the Rights of Persons with Disabilities, adopted by the United Nations in 2006, points out that disability results from the interaction between persons with impairments and attitudinal and environmental barriers that hinder their full and effective participation in society on the basis of equality with others. It stresses the importance of the right to work of persons with disabilities and, in particular, the implementation of reasonable accommodation for these persons in all workplaces. From this perspective, this article aims to explore the impacts of the legal obligation of accommodation.Methods In Canada, the fundamental rights approach and, in particular, the obligation for reasonable accommodation with regard to handicapped workers, has been well established in case law since the mid 1980s. This obligation is of a constitutional nature and its extended range is limited only by the proof of undue hardship. It thus forcefully prompts labour markets to take into consideration the needs and capacities of disabled workers. Through a study of Quebec case law, this article looks at the potential of the duty to accommodate with regard to promoting access to and retention of employment among people with mental disorders.Results The study found that the duty to accommodate imposes an innovative approach that takes into account the particular situation of the disabled person and involves the participation of all stakeholders. Accommodation allows employees to maintain an employment relationship despite

  7. 41 CFR 301-10.182 - What classes of ship accommodations are available?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 4 2013-07-01 2012-07-01 true What classes of ship...-TRANSPORTATION EXPENSES Common Carrier Transportation Ship § 301-10.182 What classes of ship accommodations are available? Accommodations on ships vary according to deck levels. (a) Other than lowest first-class—All...

  8. 41 CFR 301-10.182 - What classes of ship accommodations are available?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 4 2014-07-01 2014-07-01 false What classes of ship...-TRANSPORTATION EXPENSES Common Carrier Transportation Ship § 301-10.182 What classes of ship accommodations are available? Accommodations on ships vary according to deck levels. (a) Other than lowest first-class—All...

  9. 41 CFR 301-10.182 - What classes of ship accommodations are available?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 4 2012-07-01 2012-07-01 false What classes of ship...-TRANSPORTATION EXPENSES Common Carrier Transportation Ship § 301-10.182 What classes of ship accommodations are available? Accommodations on ships vary according to deck levels. (a) Other than lowest first-class—All...

  10. Developing Effective Academic Accommodations in Higher Education: A Collaborative Decision-Making Process

    ERIC Educational Resources Information Center

    Hsiao, Feilin; Zeiser, Shelly; Nuss, Daniel; Hatschek, Keith

    2018-01-01

    This case study describes a collaborative decision-making process for developing effective academic accommodations for a music major with a disability, whose prior accommodations suggested by the Disability Support Services (DSS) failed to address her needs. Cross-departmental collaboration between the DSS and the School of Music, as well as…

  11. 41 CFR 301-10.121 - What classes of airline accommodations are available?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... higher than coach and lower than first-class, in both cost and amenities. This class of accommodation is...-class. The basic class of accommodation by airlines that is normally the lowest fare offered regardless of airline terminology used. For reference purposes only, coach-class may also be referred to by...

  12. Accommodating Student Diversity in Remote Sensing Instruction.

    ERIC Educational Resources Information Center

    Hammen, John L., III.

    1992-01-01

    Discusses the difficulty of teaching computer-based remote sensing to students of varying levels of computer literacy. Suggests an instructional method that accommodates all levels of technical expertise through the use of microcomputers. Presents a curriculum that includes an introduction to remote sensing, digital image processing, and…

  13. A meta-analytic review of the relationship between family accommodation and OCD symptom severity.

    PubMed

    Strauss, Clara; Hale, Lucy; Stobie, Blake

    2015-06-01

    Accommodation of obsessive compulsive disorder (OCD) symptoms by family members is common. This paper presents a systematic meta-analytic review on family accommodation and OCD symptom severity. Fourteen studies investigating the relationship between family accommodation and OCD symptoms were selected. The medium effect size of the relationship between family accommodation and OCD symptom severity was significant (r = .35; 95% CI: .23 to .47), based on a Hunter-Schmidt random effects model with a total of 849 participants. Although there was some evidence of publication bias, Rosenthal's fail-safe N suggested that 596 studies with zero effect would be needed to reduce the mean effect size to non-significant. Findings are discussed in the context of the limitations of the studies, and in particular the reliance on cross-sectional designs which impede causal conclusions. Future research to evaluate a family accommodation intervention in a randomized controlled design and using mediation analysis to explore change mechanisms is called for. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Effect of vergence adaptation on convergence-accommodation: model simulations.

    PubMed

    Sreenivasan, Vidhyapriya; Bobier, William R; Irving, Elizabeth L; Lakshminarayanan, Vasudevan

    2009-10-01

    Several theoretical control models depict the adaptation effects observed in the accommodation and vergence mechanisms of the human visual system. Two current quantitative models differ in their approach of defining adaptation and in identifying the effect of controller adaptation on their respective cross-links between the vergence and accommodative systems. Here, we compare the simulation results of these adaptation models with empirical data obtained from emmetropic adults when they performed sustained near task through + 2D lens addition. The results of our experimental study showed an initial increase in exophoria (a divergent open-loop vergence position) and convergence-accommodation (CA) when viewing through +2D lenses. Prolonged fixation through the near addition lenses initiated vergence adaptation, which reduced the lens-induced exophoria and resulted in a concurrent reduction of CA. Both models showed good agreement with empirical measures of vergence adaptation. However, only one model predicted the experimental time course of reduction in CA. The pattern of our empirical results seem to be best described by the adaptation model that indicates the total vergence response to be a sum of two controllers, phasic and tonic, with the output of phasic controller providing input to the cross-link interactions.

  15. Refractive surgery for accommodative esotropia: 5-year follow-up.

    PubMed

    Magli, Adriano; Forte, Raimondo; Gallo, Flavio; Carelli, Roberta

    2014-02-01

    To assess the long-term effectiveness and safety of refractive surgery with LASIK or photorefractive keratectomy (PRK) for treating accommodative esotropia in adults. All patients with accommodative esotropia treated with LASIK or PRK until December 2007 and with a minimum follow-up of 5 years were retrospectively included. LASIK was performed on 44 eyes of 22 patients (12 women, 10 men; mean age: 22.7 ± 2.9 years). Mean postoperative follow-up was 62.1 ± 3.2 months. PRK was performed on 16 eyes of 8 patients (4 women, 4 men; mean age: 23.7 ± 1.7 years). Mean postoperative follow-up was 61.3 ± 2.8 months. At the 5-year follow-up, the mean cycloplegic refraction was more hyperopic in the PRK group (0.3 ± 0.8 vs 0.06 ± 0.3 diopters, P = .01). Correction of esotropia to esophoria or orthotropia was present in 21 patients (95.4%) treated with LASIK and in all patients treated with PRK. Both LASIK and PRK were effective in the long-term reduction of accommodative esotropia. Copyright 2014, SLACK Incorporated.

  16. Work Barriers Experienced and Job Accommodations Used by Persons with Arthritis and Other Rheumatic Diseases.

    ERIC Educational Resources Information Center

    Allaire, Saralynn H.; Li, Wei; LaValley, Michael P.

    2003-01-01

    Many people with arthritis become work disabled, but little is known about the types of work barriers they experience and their use of job accommodations. This article describes work barriers and use of accommodations and examines factors associated with accommodation use in persons with arthritis at risk for work disability. (Contains 30…

  17. The effect of longitudinal chromatic aberration on the lag of accommodation and depth of field.

    PubMed

    Jaskulski, Mateusz; Marín-Franch, Iván; Bernal-Molina, Paula; López-Gil, Norberto

    2016-11-01

    Longitudinal chromatic aberration is present in all states of accommodation and may play a role in the accommodation response and the emmetropisation process. We study the change of the depth of field (DOFi) with the state of accommodation, taking into account the longitudinal chromatic aberration. Subjective DOFi was defined as the range of defocus beyond which the blur of the target (one line of optotypes of 0.1 logMAR shown on a black-and-white microdisplay, seen through different colour filters) was perceived as objectionable. The subject's eye was paralysed and different, previously-measured accommodative states (corresponding to the accommodative demands of 0D, 2D and 4D) were simulated with a deformable mirror. Different colour conditions (monochromatic red, green and blue and polychromatic (white) were tested. The DOFi was measured subjectively, using a motorised Badal system. Taking as reference the average accommodative response for the white stimulus, the blue response exhibits on average a lead of 0.45 ± 0.09D, the green a negligible lead of 0.07 ± 0.02D and red a lag of 0.49 ± 0.10D. The monochromatic DOFi, calculated by averaging DOFi over the red, green and blue colour conditions for each accommodative demand was 1.10 ± 0.10D for 0D, 1.20 ± 0.08D for 2D, and 1.26 ± 0.40D for 4D. The polychromatic white DOFi were greater than the average monochromatic DOFi by 19%, 9% and 14% for 0D, 2D, and 4D of accommodative demand, respectively. The longitudinal chromatic aberration causes a dioptric shift of the monochromatic accommodation response. The study did not reveal this shift to depend on the accommodative demand or to have an effect on the DOFi. © 2016 The Authors Ophthalmic & Physiological Optics © 2016 The College of Optometrists.

  18. Agreement between clinical and laboratory methods assessing tonic and cross-link components of accommodation and vergence.

    PubMed

    Neveu, Pascaline; Priot, Anne-Emmanuelle; Philippe, Matthieu; Fuchs, Philippe; Roumes, Corinne

    2015-09-01

    Several tests are available to optometrists for investigating accommodation and vergence. This study sought to investigate the agreement between clinical and laboratory methods and to clarify which components are actually measured when tonic and cross-link of accommodation and vergence are assessed. Tonic vergence, tonic accommodation, accommodative vergence (AC/A) and vergence accommodation (CA/C) were measured using several tests. Clinical tests were compared to the laboratory assessment, the latter being regarded as an absolute reference. The repeatability of each test and the degree of agreement between the tests were quantified using Bland-Altman analysis. The values obtained for each test were found to be stable across repetitions; however, in most cases, significant differences were observed between tests supposed to measure the same oculomotor component. Tonic and cross-link components cannot be easily assessed because proximal and instrumental responses interfere with the assessment. Other components interfere with oculomotor assessment. Specifically, accommodative divergence interferes with tonic vergence estimation and the type of accommodation considered in the AC/A ratio affects its magnitude. Results on clinical tonic accommodation and clinical CA/C show that further investigation is needed to clarify the limitations associated with the use of difference of Gaussian as visual targets to open the accommodative loop. Although different optometric tests of accommodation and vergence rely on the same basic principles, the results of this study indicate that clinical and laboratory methods actually involve distinct components. These differences, which are induced by methodological choices, must be taken into account, when comparing studies or when selecting a test to investigate a particular oculomotor component. © 2015 The Authors. Clinical and Experimental Optometry © 2015 Optometry Australia.

  19. Supervisor and organizational factors associated with supervisor support of job accommodations for low back injured workers

    PubMed Central

    Kristman, Vicki L; Shaw, William S.; Reguly, Paula; Williams-Whitt, Kelly; Soklaridis, Sophie; Loisel, Patrick

    2016-01-01

    PURPOSE Temporary job accommodations contribute to the prevention of chronic work disability due to low back pain (LBP) through the facilitation of early return to work; yet, workplace dimensions of job accommodation are poorly understood. The objective of this study was to determine supervisor and organizational factors associated with supervisors’ support for temporary job accommodations for LBP injured workers. METHODS Supervisors were recruited from 19 workplaces in the USA and Canada and completed an online survey regarding job accommodation practices and potential associated factors with respect to a case vignette of a worker with LBP. Multivariable linear regression was used to identify the most parsimonious set of factors associated with supervisors’ support for accommodations. RESULTS A total of 804 supervisors participated with 796 eligible for inclusion in the analysis. The final set of factors explained 21% of the variance in supervisors’ support for temporary job accommodations. Considerate leadership style (β = .261; 95 % CI: .212, .310), workplace disability management policies and practices (β = .243; 95 % CI: .188, .298), and supervisor autonomy for designing and providing workplace accommodations (β = .156; 95 % CI: .071, .241) had the largest effect on supervisor support for accommodations. CONCLUSION Factors predicting supervisors’ likelihood to accommodate LBP injured workers include use of considerate leadership style, workplace disability management policies and practices, and supervisor autonomy. Workplace interventions targeting these factors should be developed and evaluated for their ability to improve work disability prevention outcomes. PMID:27032398

  20. Diurnal rhythms of visual accommodation and blink responses - Implication for flight-deck visual standards

    NASA Technical Reports Server (NTRS)

    Murphy, M. R.; Randle, R. J.; Williams, B. A.

    1977-01-01

    Possible 24-h variations in accommodation responses were investigated. A recently developed servo-controlled optometer and focus stimulator were used to obtain monocular accommodation response data on four college-age subjects. No 24-h rhythm in accommodation was shown. Heart rate and blink rate also were measured and periodicity analysis showed a mean 24-h rhythm for both; however, blink rate periodograms were significant for only two of the four subjects. Thus, with the qualifications that college students were tested instead of pilots and that they performed monocular laboratory tasks instead of binocular flight-deck tasks, it is concluded that 24-h rhythms in accommodation responses need not be considered in setting visual standards for flight-deck tasks.

  1. Synthesis of Available Accommodations for Students with Visual Impairments on Standardized Assessments

    ERIC Educational Resources Information Center

    Smith, Derrick W.; Amato, Sheila

    2012-01-01

    Because of the mandates found in the Individuals with Disabilities Education Act that specifically focus on assessment, most states have developed a set of policies that focus on the types of accommodations that can be provided to students with disabilities. Students with visual impairments require a unique set of accommodations. Braille and large…

  2. Strategies for Accommodating Extension Clients Who Face Language, Vision, or Hearing Challenges

    ERIC Educational Resources Information Center

    Angima, Sam; Etuk, Lena; Maddy, Deborah

    2016-01-01

    Extension services nationwide seek to equalize access to university resources for all learners. In this article, we focus on accommodation as a tool of our trade. We discuss findings and implications from a study that documented approaches used by one state's Extension professionals to accommodate clients who face language, vision, or hearing…

  3. The Effect of Sharing Health Information on Teachers' Production of Classroom Accommodations

    ERIC Educational Resources Information Center

    Cunningham, Melissa M.; Wodrich, David L.

    2006-01-01

    Ninety elementary-school teachers read information about a hypothetical student experiencing school-related problems due to Type 1 diabetes mellitus (T1DM), generated classroom accommodations to assist the student, and rated their confidence in these accommodations. Each teacher was provided one of three levels of information about T1DM: (a) "no…

  4. A Model of Supervisor Decision-Making in the Accommodation of Workers with Low Back Pain.

    PubMed

    Williams-Whitt, Kelly; Kristman, Vicki; Shaw, William S; Soklaridis, Sophie; Reguly, Paula

    2016-09-01

    Purpose To explore supervisors' perspectives and decision-making processes in the accommodation of back injured workers. Methods Twenty-three semi-structured, in-depth interviews were conducted with supervisors from eleven Canadian organizations about their role in providing job accommodations. Supervisors were identified through an on-line survey and interviews were recorded, transcribed and entered into NVivo software. The initial analyses identified common units of meaning, which were used to develop a coding guide. Interviews were coded, and a model of supervisor decision-making was developed based on the themes, categories and connecting ideas identified in the data. Results The decision-making model includes a process element that is described as iterative "trial and error" decision-making. Medical restrictions are compared to job demands, employee abilities and available alternatives. A feasible modification is identified through brainstorming and then implemented by the supervisor. Resources used for brainstorming include information, supervisor experience and autonomy, and organizational supports. The model also incorporates the experience of accommodation as a job demand that causes strain for the supervisor. Accommodation demands affect the supervisor's attitude, brainstorming and monitoring effort, and communication with returning employees. Resources and demands have a combined effect on accommodation decision complexity, which in turn affects the quality of the accommodation option selected. If the employee is unable to complete the tasks or is reinjured during the accommodation, the decision cycle repeats. More frequent iteration through the trial and error process reduces the likelihood of return to work success. Conclusion A series of propositions is developed to illustrate the relationships among categories in the model. The model and propositions show: (a) the iterative, problem solving nature of the RTW process; (b) decision resources necessary

  5. A model of supervisor decision-making in the accommodation of workers with low back pain

    PubMed Central

    Williams-Whitt, Kelly; Kristman, Vicki; Shaw, William S.; Soklaridis, Sophie; Reguly, Paula

    2016-01-01

    PURPOSE To explore supervisors’ perspectives and decision-making processes in the accommodation of back injured workers. METHODS Twenty-three semi-structured, in-depth interviews were conducted with supervisors from eleven Canadian organizations about their role in providing job accommodations. Supervisors were identified through an on-line survey and interviews were recorded, transcribed and entered into NVivo software. The initial analyses identified common units of meaning, which were used to develop a coding guide. Interviews were coded, and a model of supervisor decision-making was developed based on the themes, categories and connecting ideas identified in the data. RESULTS The decision-making model includes a process element that is described as iterative “trial and error” decision-making. Medical restrictions are compared to job demands, employee abilities and available alternatives. A feasible modification is identified through brainstorming and then implemented by the supervisor. Resources used for brainstorming include information, supervisor experience and autonomy, and organizational supports. The model also incorporates the experience of accommodation as a job demand that causes strain for the supervisor. Accommodation demands affect the supervisor’s attitude, brainstorming and monitoring effort and communication with returning employees. Resources and demands have a combined effect on accommodation decision complexity, which in turn affects the quality of the accommodation option selected. If the employee is unable to complete the tasks or is reinjured during the accommodation, the decision cycle repeats. More frequent iteration through the trial and error process reduces the likelihood of return to work success. CONCLUSIONS A series of propositions is developed to illustrate the relationships among categories in the model. The model and propositions show: a) the iterative, problem solving nature of the RTW process; b) decision resources

  6. Examination Accommodations for Students with Sensory Defensiveness

    ERIC Educational Resources Information Center

    Lewis, Kieran; Nolan, Clodagh

    2013-01-01

    Traditional examination accommodations include extra time, scribes, and/or separate venues for students with disabilities, which have been proven to be successful for the majority of students. For students with non-apparent disabilities such as sensory defensiveness, where sensitivity to a range of sensory information from the environment can…

  7. The availability of smoking-permitted accommodations from Airbnb in 12 Canadian cities.

    PubMed

    Kennedy, Ryan David; Douglas, Ornell; Stehouwer, Lindsay; Dawson, Jackie

    2018-01-01

    Airbnb is a web-based peer-to-peer (P2P) service that enables potential hosts and guests to broker accommodations in private homes as an alternative to traditional hotels. The hospitality sector has increasingly gone smoke-free over the last decade. This study identified the availability and cost of smoking-permitted accommodations identified on Airbnb. The study team searched for Airbnb accommodations in 12 Canadian cities across each of Canada's 10 provinces. Searches included availability for a single person for a private room, or double occupancy for an entire home/apartment; searches were for 1-night and 1-week stays. Cities across Canada, including Regina, Fredericton and Charlottetown, had no smoking-permitted accommodations available for the searches conducted. The proportion of private rooms available for one night that permitted smoking ranged from 2% in Calgary, 4% in Winnipeg and St. John's, 10% in Halifax and Victoria, 18% in Toronto, 45% in Vancouver and 69% in Montréal. The average cost for a private room for one night in Vancouver was $128, while the cost for a private room that permits smoking was $62; however, in other markets prices were more similar. Across Canada, there is a wide range of smoking-permitted accommodations available through Airbnb. In some markets, smoking-permitted accommodation may be significantly less expensive than smoke-free options. As hotel chains increasingly go smoke-free, it is possible that the marketplace will respond with offerings to fulfil consumer demand. As policy makers consider how to regulate P2P services like Airbnb, public health considerations should be included. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  8. Research-Supported Accommodation for English Language Learners in NAEP. CSE Technical Report.

    ERIC Educational Resources Information Center

    Abedi, Jamal; Courtney, Mary; Leon, Seth

    Both English language learners (ELLs) and non-ELL students in grades 4 and 8 were tested in mathematics using one of several accommodations during winter 2002. This study compared computer-, customized dictionary-, and extra-time-accommodates test results of ELL and non-ELL students. Test and questionnaire results were examined for 607 students in…

  9. Requesting Accommodation for a Disability: A Telephone Survey of American Medical Schools

    ERIC Educational Resources Information Center

    Sack, William; Gale, John; Gulati, Sanjay; Gunther, Michael; Nesheim, Robert; Stoddard, Frederick; St. John, Rachel

    2008-01-01

    Members of the committee on disabilities of the Group for the Advancement of Psychiatry (GAP) contacted 107 of 126 American Medical Schools to determine the number of students requesting accommodation for a disability, the time at which the request was made, the type of disability, and the type of accommodation offered. The survey determined that…

  10. Crystalline lens MTF measurement during simulated accommodation

    NASA Astrophysics Data System (ADS)

    Borja, David; Takeuchi, Gaku; Ziebarth, Noel; Acosta, Ana C.; Manns, Fabrice; Parel, Jean-Marie

    2005-04-01

    Purpose: To design and test an optical system to measure the optical quality of post mortem lenses during simulated accommodation. Methods: An optical bench top system was designed to measure the point spread function and calculate the modulation transfer function (MTF) of monkey and human ex-vivo crystalline lenses. The system consists of a super luminescent diode emitting at 850nm, collimated into a 3mm beam which is focused by the ex-vivo lens under test. The intensity distribution at the focus (point spread function) is re-imaged and magnified onto a beam profiler CCD camera. The optical quality in terms of spatial frequency response (modulation transfer function) is calculated by Fourier transform of the point spread function. The system was used on ex-vivo lenses with attached zonules, ciliary body and sclera. The sclera was glued to 8 separate PMMA segments and stretched radial by 5mm on an accommodation simulating lens stretching device. The point spread function was measured for each lens in the relaxed and stretched state for 5 human (ages 38-86 years) and 5 cynomolgus monkey (ages 53 - 67 months) fresh post mortem crystalline lenses. Results: Stretching induced measurable changes in the MTF. The cutoff frequency increased from 54.4+/-13.6 lp/mm unstretched to 59.5+/-21.4 lp/mm stretched in the post-presbyopic human and from 51.9+/-24.7 lp/mm unstretched to 57.7+/-18.5 lp/mm stretched cynomolgus monkey lenses. Conclusion: The results demonstrate the feasibility of measuring the optical quality of ex-vivo human and cynomolgus monkey lenses during simulated accommodation. Additional experiments are underway to quantify changes in optical quality induced by stretching.

  11. Microfluctuations in accommodation: an update on their characteristics and possible role.

    PubMed

    Charman, W Neil; Heron, Gordon

    2015-09-01

    Following the recognition, some 80 years ago, that the accommodation of the eye is not stable but fluctuates over a range of about ±0.5 D, mainly at frequencies of up to a few Hz, there has been a continuing interest in the characteristics of these microfluctuations (MFs) and their possible role in the control of accommodation. This paper reviews relevant work carried out since 1988, when we previously reviewed the same topic (Charman WN, Heron G. Fluctuations in accommodation: a review. Ophthalmic Physiol Opt 1988; 8: 153-164). Studies relating to the effects on the MFs of stimulus form, luminance and vergence are described, together with those of pupil diameter, age and ametropia. Important advances in the understanding of the links between the characteristics of the MFs and those of the cardiopulmonary system, higher-order aberrations and ocular depth-of-focus are outlined. Only limited progress has been made in understanding the role of MFs in accommodation control. While the dependence of the characteristics of the MFs in relation to observing conditions is now reasonably well understood, their involvement in accommodation control still needs clarification. The current consensus appears to be that any role is more likely to be concerned with maintaining an appropriate response, rather than in initiating responses to abrupt changes in stimulus vergence. Fluctuations at lower temporal frequencies (<0.6 Hz) are probably important to the control process, which may make use of the associated changes in the contrast and spatial frequency spectrum of the retinal image. © 2015 The Authors Ophthalmic & Physiological Optics © 2015 The College of Optometrists.

  12. Inter-individual variability in the dynamics of natural accommodation in humans: relation to age and refractive errors.

    PubMed Central

    Schaeffel, F; Wilhelm, H; Zrenner, E

    1993-01-01

    1. To study the relationship between accommodation under natural viewing conditions, age and refractive errors, we have measured time courses of accommodation in thirty-nine human subjects aged 5-49 years using a newly developed technique. The technique is based on infrared photoretinoscopy and involves fully automated on-line image processing of digitized video images of the eyes with a sampling rate of 5.3 Hz. 2. The distance between the subject and the video camera was about 1.3 m. Head movements of the subject required little restriction because the eyes were automatically tracked in the video image by the computer program. All subjects were tested under binocular viewing conditions. 3. Both refraction of the right eye and pupil diameter were measured with a precision of 0.2-0.4 dioptres (D) and 0.1 mm, respectively, and were plotted on-line. The data were subsequently automatically analysed. 4. Automated infrared photoretinoscopy proved to be very convenient and easy to handle in both children and adults. 5. The maximal speed of accommodation for a target at a distance of 5 D declined in the subjects with age (from up to 21.7 D s-1 for accommodation and 32.7 D s-1 for subsequent accommodation to a distant target ('near to far accommodation') in children down to 2-18 D s-1 in adults). There was a striking inter-individual variability in the maximum possible speed of accommodation and near to far accommodation. 6. Speed of accommodation and of near to far accommodation was correlated for each subject. However, in most of the subjects, the process of near to far accommodation was faster than accommodation (P < 0.005, if averaged over all subjects). This correlation was independent of age. 7. The accommodation-induced pupillary constriction (pupillary near response) was absent in children for a 4 D target; even at 10 D, there was no reliable pupillary response. The pupillary near response increased to about 1.6 mm D-1 of accommodation at the age of 47. Since a

  13. 33 CFR 149.641 - What are the structural fire protection requirements for accommodation spaces and modules?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... protection requirements for accommodation spaces and modules? 149.641 Section 149.641 Navigation and... the structural fire protection requirements for accommodation spaces and modules? (a) Accommodation spaces and modules must be designed, located, and constructed so as to minimize the effects of flame...

  14. Pupil movements to light and accommodative stimulation - A comparative study.

    NASA Technical Reports Server (NTRS)

    Semmlow, J.; Stark, L.

    1973-01-01

    Isolation and definition of specific response components in pupil reflexes through comparison of the dynamic features of light-induced and accommodation-induced pupil movements. A quantitative analysis of the behavior of the complex nonlinear pupil responses reveals the presence of two independent nonlinear characteristics: a range-dependent gain and a direction dependence or movement asymmetry. These nonlinear properties are attributed to motor processes because they are observable in pupil responses to both light and accommodation stimuli. The possible mechanisms and consequences of these pupil response characteristics are quantitatively defined and discussed.

  15. Interplay of late Cenozoic siliciclastic supply and carbonate response on the southeast Florida platform

    USGS Publications Warehouse

    Cunningham, K.J.; Locker, S.D.; Hine, A.C.; Bukry, D.; Barron, J.A.; Guertin, L.A.

    2003-01-01

    High-resolution seismic-reflection data collected along the length of the Caloosahatchee River in southwestern Florida have been correlated to nannofossil biostratigraphy and strontium-isotope chemostratigraphy at six continuously cored boreholes. These data are interpreted to show a major Late Miocene(?) to Early Pliocene fluvial-deltaic depositional system that prograded southward across the carbonate Florida Platform, interrupting nearly continuous carbonate deposition since early in the Cretaceous. Connection of the platform top to a continental source of siliciclastics and significant paleotopography combined to focus accumulation of an immense supply of siliciclastics on the southeastern part of the Florida Platform. The remarkably thick (> 100 m), sand-rich depositional system, which is characterized by clinoformal progradation, filled in deep accommodation, while antecedent paleotopography directed deltaic progradation southward within the middle of the present-day Florida Peninsula. The deltaic depositional system may have prograded about 200 km southward to the middle and upper Florida Keys, where Late Miocene to Pliocene siliciclastic form the foundation of the Quaternary carbonate shelf and shelf margin of the Florida Keys. These far-traveled siliciclastic deposits filled accommodation on the southeastern part of the Florida Platform so that paleobathymetry was sufficiently shallow to allow Quaternary recovery of carbonate sedimentation in the area of southern peninsular Florida and the Florida Keys.

  16. Differences in the accommodation stimulus response curves of adult myopes and emmetropes: a summary and update.

    PubMed

    Schmid, Katrina L; Strang, Niall C

    2015-11-01

    To provide a summary of the classic paper "Differences in the accommodation stimulus response curves of adult myopes and emmetropes" published in Ophthalmic and Physiological Optics in 1998 and to provide an update on the topic of accommodation errors in myopia. The accommodation responses of 33 participants (10 emmetropes, 11 early onset myopes and 12 late onset myopes) aged 18-31 years were measured using the Canon Autoref R-1 free space autorefractor using three methods to vary the accommodation demand: decreasing distance (4 m to 0.25 cm), negative lenses (0 to -4 D at 4 m) and positive lenses (+4 to 0 D at 0.25 m). We observed that the greatest accommodation errors occurred for the negative lens method whereas minimal errors were observed using positive lenses. Adult progressing myopes had greater lags of accommodation than stable myopes at higher demands induced by negative lenses. Progressing myopes had shallower response gradients than the emmetropes and stable myopes; however the reduced gradient was much less than that observed in children using similar methods. This paper has been often cited as evidence that accommodation responses at near may be primarily reduced in adults with progressing myopia and not in stable myopes and/or that challenging accommodation stimuli (negative lenses with monocular viewing) are required to generate larger accommodation errors. As an analogy, animals reared with hyperopic errors develop axial elongation and myopia. Retinal defocus signals are presumably passed to the retinal pigment epithelium and choroid and then ultimately the sclera to modify eye length. A number of lens treatments that act to slow myopia progression may partially work through reducing accommodation errors. © 2015 The Authors Ophthalmic & Physiological Optics © 2015 The College of Optometrists.

  17. Supervisor and Organizational Factors Associated with Supervisor Support of Job Accommodations for Low Back Injured Workers.

    PubMed

    Kristman, Vicki L; Shaw, William S; Reguly, Paula; Williams-Whitt, Kelly; Soklaridis, Sophie; Loisel, Patrick

    2017-03-01

    Purpose Temporary job accommodations contribute to the prevention of chronic work disability due to low back pain (LBP) through the facilitation of early return to work; yet, workplace dimensions of job accommodation are poorly understood. The objective of this study was to determine supervisor and organizational factors associated with supervisors' support for temporary job accommodations for LBP injured workers. Methods Supervisors were recruited from 19 workplaces in the USA and Canada and completed an online survey regarding job accommodation practices and potential associated factors with respect to a case vignette of a worker with LBP. Multivariable linear regression was used to identify the most parsimonious set of factors associated with supervisors' support for accommodations. Results A total of 804 supervisors participated with 796 eligible for inclusion in the analysis. The final set of factors explained 21 % of the variance in supervisors' support for temporary job accommodations. Considerate leadership style (β = 0.261; 95 % CI 0.212, 0.310), workplace disability management policies and practices (β = 0.243; 95 % CI 0.188, 0.298), and supervisor autonomy for designing and providing workplace accommodations (β = 0.156; 95 % CI 0.071, 0.241) had the largest effect on supervisor support for accommodations. Conclusion Factors predicting supervisors' likelihood to accommodate LBP injured workers include use of considerate leadership style, workplace disability management policies and practices, and supervisor autonomy. Workplace interventions targeting these factors should be developed and evaluated for their ability to improve work disability prevention outcomes.

  18. The role of interactions between accommodation and vergence in human visual development

    NASA Astrophysics Data System (ADS)

    Teel, Danielle F. W.

    Even in early infancy accommodation and vergence interact through neural coupling such that accommodation drives vergence (AC/A ratio) and vergence drives accommodation (CA/C ratio), to assist coordination and development of clear and single binocular vision. Infants have narrow inter-pupillary distances (IPD) requiring less vergence in angular units (degrees or prism diopters), and are typically hyperopic, requiring larger accommodative responses (diopters) than adults. The relative demands also change with emmetropization (decreasing hyperopia) and head growth (increasing IPD) over time. Therefore, adult-like couplings may not be optimal during development and the couplings may play a role in abnormality such as esotropia. A range of cues can drive accommodation and vergence. In addition to blur and disparity, proximity in the form of looming, size and perceived distance has been shown to influence the interactions between accommodation and vergence in adults. The role of this cue in measures of coupling is also poorly understood and may impact key clinical AC/A estimates in young children. Utilizing principles of eccentric photorefraction and Purkinje image eye tracking, this research examines the AC/A and CA/C ratios in infants, preschoolers and adults as a function of age, refractive error and interpupillary distance, plus the role proximity, specifically looming and size cues, plays in estimating the AC/A ratio in three year olds and adults. The AC/A (PD/D) was significantly higher in adults than three-year-olds or infants but similar across age groups in MA/D units. The CA/C was higher in infants than adults or three-year-olds (D/MA and D/PD). Although, not fully reciprocally related, a significant negative relationship was found between the response AC/A and CA/C. Similarly, higher AC/As (PD/D) and lower CA/Cs (D/PD) were associated with larger IPDs and less hyperopia. Although, not statistically significant the absence of proximity resulted in a trend

  19. Dynamic performance of accommodating intraocular lenses in a negative feedback control system: a simulation-based study.

    PubMed

    Schor, Clifton M; Bharadwaj, Shrikant R; Burns, Christopher D

    2007-07-01

    A dynamic model of ocular accommodation is used to simulate the stability and dynamic performance of accommodating intraocular lenses (A-IOLs) that replace the hardened natural ocular lens that is unable to change focus. Accommodation simulations of an older eye with A-IOL materials having biomechanical properties of a younger eye illustrate overshoots and oscillations resulting from decreased visco-elasticity of the A-IOL. Stable dynamics of an A-IOL are restored by adaptation of phasic and tonic neural-control properties of accommodation. Simulations indicate that neural control must be recalibrated to avoid unstable dynamic accommodation with A-IOLs. An interactive web-model of A-IOL illustrating these properties is available at http://schorlab.berkeley.edu.

  20. Accommodating Faculty Members Who Have Disabilities. Report

    ERIC Educational Resources Information Center

    American Association of University Professors, 2012

    2012-01-01

    In recent years the rights and responsibilities of students who have disabilities have received considerable attention. Professors routinely accommodate students with a front-row seat in class or extended time on an examination. Faculty members who have disabilities have received far less attention. This report from a subcommittee of Committee A…

  1. Anterior segment biometry during accommodation imaged with ultra-long scan depth optical coherence tomography

    PubMed Central

    Du, Chixin; Shen, Meixiao; Li, Ming; Zhu, Dexi; Wang, Michael R.; Wang, Jianhua

    2012-01-01

    Purpose To measure by ultra-long scan depth optical coherence tomography (UL-OCT) dimensional changes in the anterior segment of human eyes during accommodation. Design Evaluation of diagnostic test or technology. Participants Forty-one right eyes of healthy subjects with a mean age of 34 years (range, 22–41 years) and a mean refraction of −2.5±2.6 diopters (D) were imaged in two repeated measurements at minimal and maximal accommodation. Methods A specially adapted designed UL-OCT instrument was used to image from the front surface of the cornea to the back surface of the crystalline lens. Custom software corrected the optical distortion of the images and yielded the biometric measurements. The coefficient of repeatability (COR) and the intraclass correlation coefficient (ICC) were calculated to evaluate the repeatability and reliability. Main Outcome Measures Anterior segment parameters and associated repeatability and reliability upon accommodation. The dimensional results included central corneal thickness (CCT), anterior chamber depth and width (ACD, ACW), pupil diameter (PD), lens thickness (LT), anterior segment length (ASL=ACD+LT), lens central position (LCP=ACD+1/2LT) and horizontal radii of the lens anterior and posterior surface curvatures (LAC, LPC). Results Repeated measurements of each variable within each accommodative state did not differ significantly (P>0.05). The CORs and ICCs for CCT, ACW, ACD, LT, LCP, and ASL were excellent (1.2% to 3.59% and 0.998 to 0.877, respectively). They were higher for PD (18.90% to 21.63% and 0.880 to 0.874, respectively), and moderate for LAC and LPC (34.86% to 42.72% and 0.669 to 0.251, respectively) in the two accommodative states. Compared to minimal accommodation, PD, ACD, LAC, LPC, and LCP decreased and LT and ASL increased significantly at maximal accommodation (P<0.05), while CCT and ACW did not change (P>0.05). Conclusions UL-OCT measured changes in anterior segment dimensions during accommodation with

  2. Accommodating environmental variation in population models: metaphysiological biomass loss accounting.

    PubMed

    Owen-Smith, Norman

    2011-07-01

    1. There is a pressing need for population models that can reliably predict responses to changing environmental conditions and diagnose the causes of variation in abundance in space as well as through time. In this 'how to' article, it is outlined how standard population models can be modified to accommodate environmental variation in a heuristically conducive way. This approach is based on metaphysiological modelling concepts linking populations within food web contexts and underlying behaviour governing resource selection. Using population biomass as the currency, population changes can be considered at fine temporal scales taking into account seasonal variation. Density feedbacks are generated through the seasonal depression of resources even in the absence of interference competition. 2. Examples described include (i) metaphysiological modifications of Lotka-Volterra equations for coupled consumer-resource dynamics, accommodating seasonal variation in resource quality as well as availability, resource-dependent mortality and additive predation, (ii) spatial variation in habitat suitability evident from the population abundance attained, taking into account resource heterogeneity and consumer choice using empirical data, (iii) accommodating population structure through the variable sensitivity of life-history stages to resource deficiencies, affecting susceptibility to oscillatory dynamics and (iv) expansion of density-dependent equations to accommodate various biomass losses reducing population growth rate below its potential, including reductions in reproductive outputs. Supporting computational code and parameter values are provided. 3. The essential features of metaphysiological population models include (i) the biomass currency enabling within-year dynamics to be represented appropriately, (ii) distinguishing various processes reducing population growth below its potential, (iii) structural consistency in the representation of interacting populations and

  3. Accommodation and the Visual Regulation of Refractive State in Marmosets

    PubMed Central

    Troilo, David; Totonelly, Kristen; Harb, Elise

    2009-01-01

    Purpose To determine the effects of imposed anisometropic retinal defocus on accommodation, ocular growth, and refractive state changes in marmosets. Methods Marmosets were raised with extended-wear soft contact lenses for an average duration of 10 wks beginning at an average age of 76 d. Experimental animals wore either a positive or negative contact lens over one eye and a plano lens or no lens over the other. Another group wore binocular lenses of equal magnitude but opposite sign. Untreated marmosets served as controls and three wore plano lenses monocularly. Cycloplegic refractive state, corneal curvature, and vitreous chamber depth were measured before, during, and after the period of lens wear. To investigate the accommodative response, the effective refractive state was measured through each anisometropic condition at varying accommodative stimuli positions using an infrared refractometer. Results Eye growth and refractive state are significantly correlated with the sign and power of the contact lens worn. The eyes of marmosets reared with monocular negative power lenses had longer vitreous chambers and were myopic relative to contralateral control eyes (p<0.01). Monocular positive power lenses produced a significant reduction in vitreous chamber depth and hyperopia relative to the contralateral control eyes (p<0.05). In marmosets reared binocularly with lenses of opposite sign, we found larger interocular differences in vitreous chamber depths and refractive state (p<0.001). Accommodation influences the defocus experienced through the lenses, however, the mean effective refractive state was still hyperopia in the negative-lens-treated eyes and myopia in the positive-lens-treated eyes. Conclusions Imposed anisometropia effectively alters marmoset eye growth and refractive state to compensate for the imposed defocus. The response to imposed hyperopia is larger and faster than the response to imposed myopia. The pattern of accommodation under imposed

  4. Accommodation Decision Making for Postsecondary Students with Learning Disabilities: Individually Tailored or One Size Fits All?

    ERIC Educational Resources Information Center

    Weis, Robert; Dean, Emily L.; Osborne, Karen J.

    2016-01-01

    Clinicians uniformly recommend accommodations for college students with learning disabilities; however, we know very little about which accommodations they select and the validity of their recommendations. We examined the assessment documentation of a large sample of community college students receiving academic accommodations for learning…

  5. Determining the relative contribution of retinal disparity and blur cues to ocular accommodation in Down syndrome.

    PubMed

    Doyle, Lesley; Saunders, Kathryn J; Little, Julie-Anne

    2017-01-10

    Individuals with Down syndrome (DS) often exhibit hypoaccommodation alongside accurate vergence. This study investigates the sensitivity of the two systems to retinal disparity and blur cues, establishing the relationship between the two in terms of accommodative-convergence to accommodation (AC/A) and convergence-accommodation to convergence (CA/C) ratios. An objective photorefraction system measured accommodation and vergence under binocular conditions and when retinal disparity and blur cues were removed. Participants were aged 6-16 years (DS n = 41, controls n = 76). Measures were obtained from 65.9% of participants with DS and 100% of controls. Accommodative and vergence responses were reduced with the removal of one or both cues in controls (p < 0.007). For participants with DS, removal of blur was less detrimental to accommodative responses than removal of disparity; accommodative responses being significantly better when all cues were available or when blur was removed in comparison to when proximity was the only available cue. AC/A ratios were larger and CA/C ratios smaller in participants with DS (p < 0.00001). This study demonstrates that retinal disparity is the main driver to both systems in DS and illustrates the diminished influence of retinal blur. High AC/A and low CA/C ratios in combination with disparity-driven responses suggest prioritisation of vergence over accurate accommodation.

  6. Determining the relative contribution of retinal disparity and blur cues to ocular accommodation in Down syndrome

    PubMed Central

    Doyle, Lesley; Saunders, Kathryn J.; Little, Julie-Anne

    2017-01-01

    Individuals with Down syndrome (DS) often exhibit hypoaccommodation alongside accurate vergence. This study investigates the sensitivity of the two systems to retinal disparity and blur cues, establishing the relationship between the two in terms of accommodative-convergence to accommodation (AC/A) and convergence-accommodation to convergence (CA/C) ratios. An objective photorefraction system measured accommodation and vergence under binocular conditions and when retinal disparity and blur cues were removed. Participants were aged 6–16 years (DS n = 41, controls n = 76). Measures were obtained from 65.9% of participants with DS and 100% of controls. Accommodative and vergence responses were reduced with the removal of one or both cues in controls (p < 0.007). For participants with DS, removal of blur was less detrimental to accommodative responses than removal of disparity; accommodative responses being significantly better when all cues were available or when blur was removed in comparison to when proximity was the only available cue. AC/A ratios were larger and CA/C ratios smaller in participants with DS (p < 0.00001). This study demonstrates that retinal disparity is the main driver to both systems in DS and illustrates the diminished influence of retinal blur. High AC/A and low CA/C ratios in combination with disparity-driven responses suggest prioritisation of vergence over accurate accommodation. PMID:28071728

  7. Supervisor Autonomy and Considerate Leadership Style are Associated with Supervisors' Likelihood to Accommodate Back Injured Workers.

    PubMed

    McGuire, Connor; Kristman, Vicki L; Shaw, William; Williams-Whitt, Kelly; Reguly, Paula; Soklaridis, Sophie

    2015-09-01

    To determine the association between supervisors' leadership style and autonomy and supervisors' likelihood of supporting job accommodations for back-injured workers. A cross-sectional study of supervisors from Canadian and US employers was conducted using a web-based, self-report questionnaire that included a case vignette of a back-injured worker. Autonomy and two dimensions of leadership style (considerate and initiating structure) were included as exposures. The outcome, supervisors' likeliness to support job accommodation, was measured with the Job Accommodation Scale (JAS). We conducted univariate analyses of all variables and bivariate analyses of the JAS score with each exposure and potential confounding factor. We used multivariable generalized linear models to control for confounding factors. A total of 796 supervisors participated. Considerate leadership style (β = .012; 95% CI .009-.016) and autonomy (β = .066; 95% CI .025-.11) were positively associated with supervisors' likelihood to accommodate after adjusting for appropriate confounding factors. An initiating structure leadership style was not significantly associated with supervisors' likelihood to accommodate (β = .0018; 95% CI -.0026 to .0061) after adjusting for appropriate confounders. Autonomy and a considerate leadership style were positively associated with supervisors' likelihood to accommodate a back-injured worker. Providing supervisors with more autonomy over decisions of accommodation and developing their considerate leadership style may aid in increasing work accommodation for back-injured workers and preventing prolonged work disability.

  8. [Comparative evaluation of the effectiveness of various treatment modalities for accommodation disorders and acquired progressive myopia].

    PubMed

    Tarutta, E P; Tarasova, N A

    2015-01-01

    To evaluate the effectiveness of non-surgical treatment of accommodation disorders and progressive myopia in children. A total of 190 patients (380 eyes) with myopia aged from 6 to 18 years (10.79±0.18 years on average) were enrolled and divided into 9 groups depending on the treatment prescribed. Comparative evaluation of different hardware-based treatment modalities for progressive myopia allowed to work out their optimal combination: "Visotronic", "MACDEL 09", and magnetophoresis of Taufon 4%. Such courses, provided twice a year, were associated with optimization of accommodative response and 1.9-2.8 times reduction of the rate of myopia progression. On the contrary, pleoptic therapy showed a negative effect on accommodative tonus and the rate of progression of acquired myopia. Comparative evaluation of different hardware-based treatment modalities for progressive myopia and accommodation disorders allowed to work out their optimal combination: "Visotronic", "MACDEL 09" and magnetophoresis of Taufon 4%. This treatment, provided twice a year, allows to increase accommodative reserves and volume, improve objective accommodative response, and reduce accommodative hypertonus as well as the rate of myopia progression (1.9-2.8 times over a 1.5-year period). Under pleoptic therapy (specialized software, near field speckles, color pulse therapy, Ambliokor device), both accommodative tonus and the rate of myopia progression increased (1.3-1.5 and 1.6 times correspondingly).

  9. Kinematic and ground reaction force accommodation during weighted walking.

    PubMed

    James, C Roger; Atkins, Lee T; Yang, Hyung Suk; Dufek, Janet S; Bates, Barry T

    2015-12-01

    Weighted walking is a functional activity common in daily life and can influence risks for musculoskeletal loading, injury and falling. Much information exists about weighted walking during military, occupational and recreational tasks, but less is known about strategies used to accommodate to weight carriage typical in daily life. The purposes of the study were to examine the effects of weight carriage on kinematics and peak ground reaction force (GRF) during walking, and explore relationships between these variables. Twenty subjects walked on a treadmill while carrying 0, 44.5 and 89 N weights in front of the body. Peak GRF, sagittal plane joint/segment angular kinematics, stride length and center of mass (COM) vertical displacement were measured. Changes in peak GRF and displacement variables between weight conditions represented accommodation. Effects of weight carriage were tested using analysis of variance. Relationships between peak GRF and kinematic accommodation variables were examined using correlation and regression. Subjects were classified into sub-groups based on peak GRF responses and the correlation analysis was repeated. Weight carriage increased peak GRF by an amount greater than the weight carried, decreased stride length, increased vertical COM displacement, and resulted in a more extended and upright posture, with less hip and trunk displacement during weight acceptance. A GRF increase was associated with decreases in hip extension (|r|=.53, p=.020) and thigh anterior rotation (|r|=.57, p=.009) displacements, and an increase in foot anterior rotation displacement (|r|=.58, p=.008). Sub-group analysis revealed that greater GRF increases were associated with changes at multiple sites, while lesser GRF increases were associated with changes in foot and trunk displacement. Weight carriage affected walking kinematics and revealed different accommodation strategies that could have implications for loading and stability. Copyright © 2015 Elsevier B

  10. Teachers' Perceptions Regarding the Effectiveness of Accommodations for Students with Specific Learning Disabilities

    ERIC Educational Resources Information Center

    Lipscomb, Tanyaneka T.

    2012-01-01

    Research suggests that teachers may have several perceptions about the use and effectiveness of accommodations for students with specific learning disabilities. This quantitative study investigated regular education and special education teachers' perceptions toward the use of testing and instructional accommodations for students with specific…

  11. The Willingness and Ability of Postsecondary Faculty to Provide Academic Accommodations to Students with Learning Disabilities

    ERIC Educational Resources Information Center

    McCarron, Elizabeth C.

    2017-01-01

    Faculty are responsible for providing the academic accommodations needed and used by students with learning disabilities (SWLD). Since learning disabilities (LD) are hidden, faculty may question the need for, efficacy of, and fairness of accommodations. Yet academically accommodating SWLD is important to academic success and persistence. This…

  12. The standpoint of persons with hearing loss on work disparities and workplace accommodations.

    PubMed

    Shaw, Lynn; Tetlaff, Britta; Jennings, Mary Beth; Southall, Kenneth E

    2013-01-01

    The perspectives of persons who live and work with hearing loss were sought to examine workplace accommodation challenges and strategies. A convenience sample of seven older adults with hearing loss participated in in-depth interviews. A systematic grounded theory approach informed the study design and analysis. Categories of facilitators and challenges in the data were identified through axial coding and clustering. Core categories of social processes emerged through constant comparison and theoretical sampling of the data to reveal the actions and interactions used to negotiate or implement adaptations or workplace accommodations. Persons with hearing loss use a realm of strategies to live and work with a hearing loss. Social processes used to navigate the challenges to working with hearing loss and to manage optimal work performance included: self-accommodation, self-advocacy, self-management of hearing loss, and lobbying. Success in overcoming work disparities for persons with hearing loss requires individuals to take control of identifying their needs within the workplace and at home, and to negotiate for specific accommodations. These strategies and processes draw attention to the need for a repository on contextualized workplace accommodation strategies for improving communication and hearing in the workplace. Further to this a best practice guide for use by workers, employers, and work rehabilitation and health care workers is indicated.

  13. Is there any evidence for the validity of diagnostic criteria used for accommodative and nonstrabismic binocular dysfunctions?

    PubMed Central

    Cacho-Martínez, Pilar; García-Muñoz, Ángel; Ruiz-Cantero, María Teresa

    2013-01-01

    Purpose To analyze the diagnostic criteria used in the scientific literature published in the past 25 years for accommodative and nonstrabismic binocular dysfunctions and to explore if the epidemiological analysis of diagnostic validity has been used to propose which clinical criteria should be used for diagnostic purposes. Methods We carried out a systematic review of papers on accommodative and non-strabic binocular disorders published from 1986 to 2012 analysing the MEDLINE, CINAHL, PsycINFO and FRANCIS databases. We admitted original articles about diagnosis of these anomalies in any population. We identified 839 articles and 12 studies were included. The quality of included articles was assessed using the QUADAS-2 tool. Results The review shows a wide range of clinical signs and cut-off points between authors. Only 3 studies (regarding accommodative anomalies) assessed diagnostic accuracy of clinical signs. Their results suggest using the accommodative amplitude and monocular accommodative facility for diagnosing accommodative insufficiency and a high positive relative accommodation for accommodative excess. The remaining 9 articles did not analyze diagnostic accuracy, assessing a diagnosis with the criteria the authors considered. We also found differences between studies in the way of considering patients’ symptomatology. 3 studies of 12 analyzed, performed a validation of a symptom survey used for convergence insufficiency. Conclusions Scientific literature reveals differences between authors according to diagnostic criteria for accommodative and nonstrabismic binocular dysfunctions. Diagnostic accuracy studies show that there is only certain evidence for accommodative conditions. For binocular anomalies there is only evidence about a validated questionnaire for convergence insufficiency with no data of diagnostic accuracy. PMID:24646897

  14. Supervisors' perceptions of organizational policies are associated with their likelihood to accommodate back-injured workers.

    PubMed

    McGuire, Connor; Kristman, Vicki L; Shaw, William S; Loisel, Patrick; Reguly, Paula; Williams-Whitt, Kelly; Soklaridis, Sophie

    2017-02-01

    Background Low back pain (LBP) is a major concern among North American workplaces and little is known regarding a supervisor's decision to support job accommodation for workers with LBP. The extent to which supervisors are included in a company's effort to institute disability management policies and practices and workplace safety climate are two factors that may influence a supervisor's decision to accommodate workers with LBP. Objective Determine the association between supervisors' perceptions of disability management policies, corporate safety culture and their likelihood of supporting job accommodations for workers with LBP. Methods We conducted a cross-sectional study of supervisors (N=796) recruited from a non-random, convenience sample of 19 Canadian and US employers. The outcome was supervisors' likeliness to support job accommodation and the exposure was global work safety culture and disability management policies and practices. A multivariable generalized linear modelling strategy was used and final models for each exposure were obtained after assessing potential effect modifiers and confounders. Results In the study, 796 eligible supervisors from 19 employers participated. Disability management policies and practices were positively associated with supervisors' likeliness to accommodate (β=0.19; 95% CI: 0.13; 0.24) while no significant association was found between corporate safety culture (β= -0.084; 95% CI: -0.19; 0.027) and supervisors' likeliness to accommodate. Conclusions Employers should ensure that proactive disability management policies and practices are clearly communicated to supervisors in order to improve job modification and return to work efforts. Implications for Rehabilitation Low back pain (LBP) is a major workplace concern and little is known regarding what factors are associated with a supervisor's likelihood to support job accommodation for workers with LBP. The objective of this article was to determine the association

  15. Unflagged SATs: Who Benefits from Special Accommodations?

    ERIC Educational Resources Information Center

    Abrams, Samuel J.

    2005-01-01

    When the College Board announced, in the summer of 2002, that it would stop "flagging" the test scores of students who were given special accommodations for the SAT, the gold standard exam for college admission, disability advocates were thrilled. "A triumphant day for millions of people with dyslexia and other disabilities,"…

  16. EEOC claims employer refused reasonable accommodation. Equal Employment Opportunity Commission.

    PubMed

    1995-06-30

    The Equal Employment Opportunity Commission (EEOC) has sued Spectacor, one of the largest stadium-management companies, on behalf of employee [name removed]. [Name removed], who claimed his employer refused to grant him flexible work hours to accommodate his AIDS diagnosis. [Name removed] had submitted a note from one of his doctors stating that [name removed] had AIDS and was taking an experimental medicine. The doctors requested some added flexibility in working hours to enable [name removed] to prepare special meals and take showers to reduce the discomfort of the experimental medicines he was taking. Spectacor, instead of granting the request, informed [name removed] that his job was in jeopardy and that he would be discharged because of absenteeism and declining productivity. The suit alleges Spectacor violated the Americans with Disabilities Act (ADA) by refusing to grant [name removed] a reasonable accommodation for his disability and that the employer had breached its obligation to keep confidential his medical information. Spectacor denied that its refusal to accommodate [name removed]'s scheduling requests constituted a violation of the ADA.

  17. School nurses' familiarity and perceptions of academic accommodations for student-athletes following sport-related concussion.

    PubMed

    Weber, Michelle L; Welch, Cailee E; Parsons, John T; Valovich McLeod, Tamara C

    2015-04-01

    The purpose of this study was to evaluate school nurses' familiarity and perceptions regarding academic accommodations for student-athletes following sport-related concussion. School nurses (N = 1,246) accessed the survey School Nurses' Beliefs, Attitudes and Knowledge of Pediatric Athletes with Concussions (BAKPAC-SN). The BAKPAC-SN contained several questions pertaining to concussion management and academic accommodations. There were significant differences regarding personal experience as well as familiarity of academic accommodations (p < .001) between school nurses who work at a school that employs an athletic trainer and school nurses who work at a school that does not employ an athletic trainer. There were significant weak positive relationships between years of experience and familiarity with academic accommodations (r = .210, p < .001), 504 plans (r = .243, p < .001), and individualized education plans (r = .205, p < .001). School nurses employed at a single school were significantly more familiar with academic accommodations (p = .027) and 504 plans (p = .001) than school nurses employed at multiple schools. Health care professionals should collaborate to effectively manage a concussed patient and should consider academic accommodations to ensure whole-person health care. © The Author(s) 2014.

  18. Is cratonic sedimentation consistent with available models? An example from the Upper Proterozoic of the West African craton

    NASA Astrophysics Data System (ADS)

    Bertrand-Sarfati, Janine; Moussine-Pouchkine, Alexis

    1988-08-01

    The Atar Group, part of the Upper Proterozoic sequence covering the West African craton, stable since 2000 Ma, is characterized by an alternation of extensive carbonate beds and mixed siliciclastic and carbonate facies. The carbonate beds comprise essentially columnar stromatolite biostromes and bioherms which reflect sublittoral environments. The mixed facies contain a variety of laterally discontinuous facies which imply more variable environmental conditions. The settings of the mixed facies are not always clear but they do not contain thick sequences of high-energy facies. Few obvious facies sequences are discernable; those that are present are considered to be punctuated aggradational cycles (PACs) and they always start with biostromes of columnar stromatolites with very few sediments. Composite sequences are interpreted as due to shallowing upward or increasing energy environments that may be laterally contiguous, despite the fact that the contacts are not gradational. However, much of the stratigraphic sequence cannot be subdivided into cycles and seems to consist of unrelated individual facies, bound by sharp boundaries. The basin analysis reveals that biostromes of columnar stromatolites start after an instantaneous geological event corresponding to a sea-level rise. Consequently, their appearance can be considered as a time-line. We describe, in the Atar Group and its equivalents, three sedimentation trends, all of which are interpreted to be of shallowing upward character. The Atar Group appears to have been deposited in an epeiric sea (i.e. an extremely flat ramp). There are two contrasting styles of sedimentation: (1) after the submergence of the whole area, columnar stromatolites built extensive biostromes; (2) during the stable phase, sediments are deposited in a mosaic of laterally-discontinuous facies. Tidal influence cannot be recognized in the sequence, neither can a salinity increase toward the land; both common features in published epeiric sea

  19. Columbus stowage optimization by cast (cargo accommodation support tool)

    NASA Astrophysics Data System (ADS)

    Fasano, G.; Saia, D.; Piras, A.

    2010-08-01

    A challenging issue related to the International Space Station utilization concerns the on-board stowage, implying a strong impact on habitability, safety and crew productivity. This holds in particular for the European Columbus laboratory, nowadays also utilized to provide the station with logistic support. The volume exploitation has to be maximized, in compliance with the given accommodation rules. At each upload step, the stowage problem must be solved quickly and efficiently. This leads to the comparison of different scenarios to select the most suitable one. Last minute upgrades, due to possible re-planning, may, moreover arise, imposing the further capability to rapidly readapt the current solution to the updated status. In this context, looking into satisfactory solutions represents a very demanding job, even for experienced designers. Thales Alenia Space Italia has achieved a remarkable expertise in the field of cargo accommodation and stowage. The company has recently developed CAST, a dedicated in-house software tool, to support the cargo accommodation of the European automated transfer vehicle. An ad hoc version, tailored to the Columbus stowage, has been further implemented and is going to be used from now on. This paper surveys the on-board stowage issue, pointing out the advantages of the proposed approach.

  20. 41 CFR 301-10.183 - What class of ship accommodations must I use?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... accommodations must I use? 301-10.183 Section 301-10.183 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES ALLOWABLE TRAVEL EXPENSES 10-TRANSPORTATION EXPENSES... use the lowest first-class accommodations when traveling by ship, except when your agency specifically...